bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term changes in bone mass after partial gastrectomy in a well‐defined population and its relation to tobacco and alcohol consumption
Authors: Krogsgaard Michael R. , Frølich Anne , Lund Birger , Lund Bjarne
Published: December 2004

We studied the long‐term effect of partial gastrectomy on bone metabolism in a well defined population of gastrectomized patients compared to an age‐ and sex‐matched group with unoperated peptic ulcers (controls). We selected 61 individuals between 61 and 70 years old at the time of investigation who had been operated on at the same surgical department an average of 20 years earlier. Compared to unoperated ulcer patients, we found reduced bone mass of the distal forearm in the operated groups. The serum level of calcidiol was significantly reduced in Billroth I (BI) operated women and insignificantly lower in the other operated groups. In men, ionized and total calcium was reduced, and 24‐hour excretion of hydroxyproline in the urine was increased (p(0.05). Biochemical signs of osteomalacia were found in one gastrectomized patient only. There were no significant differences between operated and unoperated patients in serum levels of alkaline phosphatases, iPTH, calcitriol, or the 24‐hour urine calcium/creatinine excretion, even though there was a trend towards lower 24‐hour urine calcium/creatinine ratio and increased levels of iPTH in the operated groups. There was no correlation between the daily alcohol consumption or cumulative tobacco consumption and bone mineral content in each group. Gastrectomized women smoked much more than control women, and smoking may be a determinant factor for the bone loss, as it is in healthy persons. Operated patients had a lower intake of milk products. All patients were exposed to sunlight for more than 3 hours/week. It is suggested that osteopenia after gastrectomy might be caused by calcium depletion rather than lack of vitamin D. The consumption of tobacco but not of alcohol was connected to bone loss.
Fenestration in the management of polycystic liver disease
Authors: Farges Olivier , Bismuth Henri
Published: December 2004

Thirteen patients with symptomatic polycystic liver disease who were selected for fenestration were reviewed. The main preoperative complaints that related to polycystic liver disease were severe abdominal pain, respiratory distress, clinical ascites, or leg edema. All symptoms disappeared after operation, and the number and size of the cysts were smaller. Five patients developed transient but massive ascites during the postoperative period, and long‐term follow‐up demonstrated a moderate recurrence of hepatomegaly in two patients. These postoperative complications and failures appeared to be at least partly related to a more extensive evolution of the disease in the patients in whom it developed.
Nonsurgical treatment of hepatocellular carcinoma in cirrhotic patients
Authors: Ohto Masao , Yoshikawa Masaharu , Saisho Hiromitsu , Ebara Masaaki , Sugiura Nobuyuki
Published: December 2004

Modern imaging modalities have allowed us to make reliable diagnosis of hepatocellular carcinoma (HCC). Most of HCCs are associated with liver cirrhosis in varying stages of severity and often accompanied by new occurrences of HCC after treatment. Now, newly developed nonsurgical therapeutic modalities are used extensively and achieve good results in terms of anti‐tumor effects as well as post‐treatment survival.
Neuroendocrine metastases of the liver
Authors: Ihse Ingemar , Persson Bo , Tibblin Sten
Published: December 2004

Neuroendocrine liver metastases are rare, yet they represent an entity that has attracted much attention lately. The protracted course of neuroendocrine tumors and the hormone origin of their typical incapacitating symptoms constitute a logical basis for well founded and bespoke treatment. Demonstration of the liver secondaries is best done by ultrasonography (US) and contrast‐enhanced computed tomography (CT), which on the whole have replaced the invasive angiography techniques. By use of histochemical and molecular biologic methods the exact nature of the tumor can be typified in tissue samples obtained percutaneously, laparoscopically, or surgically. Localization of nonpalpable metastases of the liver is best done by intraoperative US. Surgical removal of liver metastases is curative in some cases and is usually effective in relieving the symptoms. Also, palliative debulking or cytoreductive surgery is often worthwhile as it offers a chance of prolonged survival and symptom relief. Similar benefits are achieved by ischemic therapy preferably by temporary dearterialization, which in our department is done on an outpatient basis using a specially designed (externally controlled) occluder applied during a single laparotomy that includes debulking when appropriate as well as cholecystectomy. Hormonal therapy with somatostatin analogs may be used as a single treatment or in combination with ischemic therapy. It has an ensured symptom‐reducing effect, whereas its influence on tumor growth is unsettled. Lately similar effects have been ascribed to human leukocyte interferon. In conclusion the specific characteristics of neuroendocrine tumors and the available treatment arsenal favor an active treatment approach in patients who have developed liver metastases.
Resection and bypass for malignant obstruction of the bile duct
Authors: Myburgh J. Albertus
Published: December 2004

Ninety‐one patients with malignant biliary obstruction, excluding carcinoma of the head of the pancreas and periampullary cancer, are analyzed. Sixty‐five patients had hilar tumors, 32 Klatskin tumors, and 33 malignant hilar biliary obstructions due to primary carcinoma of the gallbladder or metastatic spread to the hilum from other primary sites (pseudo‐Klatskin tumors). There were 9 patients with carcinoma of the middle third and 16 patients with carcinoma of the lower third of the bile duct. Resection rates were 31% (10 of 32) for Klatskin tumors, 3% (1 of 33) for pseudo‐Klatskin tumors, 22% (2 of 9) for carcinomas of the middle third, and 88% (14 of 16) for carcinomas of the lower third of the bile duct. Jaundice was completely relieved in all patients undergoing resection. Three patients are alive 2 months, 8 years, and 7 years, respectively, after resection of Klatskin tumors and 5 of the 16 patients with resection of lower third carcinomas are alive 8 months to 9 years after operation, respectively. Surgical bypass by the Hepp or Soupault approaches to the left duct or to the duct of segment V of the right lobe was used in 47% of patients with Klatskin tumors and 58% of patients with pseudo‐Klatskin tumours. Median survival times were 6 months and 4 months, respectively, in these two groups. Surgical bypass was used in 67% of patients with carcinoma of the middle third and 13% of patients with carcinoma of the lower third of the bile duct. Median survival time was 6 months. Prosthetic bypass was used in patients considered unfit for major surgical intervention (9% of patients with Klatskin tumors, 14% of patients with pseudo‐Klatskin tumors, and one patient with carcinoma of the middle third). Survival times were only days to weeks after intervention. In seven patients (7.7%) there was no active intervention on the grounds of the patients' condition or the advanced stage of the disease. Resection offers the only chance of cure and is feasible in most patients with carcinoma of the lower third and in a substantial number of patients with Klatskin tumors. Operative bypass results in high quality palliation for meaningful periods in patients with Klatskin tumors, but the duration of palliation in patients with pseudo‐Klatskin tumors is disappointingly short. The overall dividend in this subgroup is questionable in view of the advanced stage of the disease at presentation, and some or most of these patients should probably fall into the category where a decision not to intervene actively by either operative or nonoperative means appears to be the most appropriate and humane course of action.
New method for measuring ICG Rmax with a clearance meter
Authors: Shimizu Shigeomi , Kamiike Wataru , Hatanaka Nobutaka , Yoshida Yukuo , Tagawa Kunio , Miyata Masahiko , Matsuda Hikaru
Published: December 2004

The maximal removal rate of indocyanine green (ICG Rmax) is considered to be an important parameter of hepatic function. However, the method of analysis has some flaws, and an abnormal value is obtained for about 15% of patients. We developed a new method of measuring the ICG Rmax with a clearance meter (RK‐1000) that continuously measured the ICG concentration using a fingertip optical sensor. Twenty patients were examined. The histologic diagnosis was as follows: normal for 10, cirrhosis in 6, hepatitis in 4. The ICG concentration was measured in vivo continously with the RK‐1000. To obtain the Rmax by the Michaelis‐Menten model, the ICG concentration in the VLDL compartment was subtracted from the values obtained by the RK‐1000 because ICG binds to various serum proteins and its rate of removal in the VLDL compartment differs from that in other protein compartments. The removal velocity was calculated and a Michaelis plot obtained. Then Rmax was calculated from the reciprocal of the y‐intercept of a Lineweaver‐Burk plot. The Rmax in subjects with liver disease was signficantly lower than in those with normal liver. It is concluded that our new method of measuring ICG Rmax with the RK‐1000 reflects liver function appropriately.
Functional results after treatment of rectal prolapse with rectopexy and sigmoid resection
Authors: Huber F. T. , Stein H. , Siewert J. R.
Published: December 2004

Constipation and incontinence are frequent complications of rectal prolapse. Surgery should not only aim to correct prolapse but also improve bowel and sphincter function. From 1986–1991 42 patients with procidentia were treated by rectopexy and sigmoid resection. The mean age was 61.1 years. Thirty‐nine patients were available for follow‐up examination. Mean follow‐up was 54 months. Functional data were collected prospectively before the operation and at follow‐up and included clinical parameters, a constipation score, an incontinence score, anal manometry [mean resting pressure (MRP), mean maximum pressure (MMP)], proctography [anorectal angle (ARA)] and colonic transit studies [mean transit time (MTT), rectosigmoid transit time (RSTT)]. The postoperative complication rate was 7.1% (n=3), mortality was 0%. No recurrence was seen. Constipation complaints improved from 43.6% to 25.6% (p<0.001) and incontinence from 66.6% to 23.1% (p<0.001). MRP increased from 36.5 mmHg to 46.0 mmHg and MMP from 90.5 mmHg to 103.0 mmHg (p<0.001). ARA changed from 102 to 98 degrees (p<0.001) and correlated with sphincter tone and continence. MTT decreased from 47.8 to 38.5 hours, segmental transit (RSTT) from 21.1 to 12.7 hours (p<0.001). Our results indicate that rectopexy with sigmoid resection is a safe and effective procedure for rectal prolapse and improves functional disorders of bowel and sphincter.
Management of in situ and minimally invasive breast carcinoma
Authors: Frykberg Eric R. , Bland Kirby I.
Published: December 2004

In situ breast carcinoma represents an early localized stage in the transition to invasive breast carcinoma and has an especially favorable prognosis with appropriate management. The widespread use of mammography has contributed to its increased rate of diagnosis. The two histologic forms of this entity have distinct pathologic and biologic characteristics, with different therapeutic implications. Lobular carcinoma in situ is considered a marker of increased risk for subsequent invasive carcinoma and is most commonly managed by nonoperative surveillance. Ductal carcinoma in situ behaves more as a true anatomic precursor of invasive disease and has the same therapeutic options as invasive breast carcinoma. Minimally invasive breast carcinoma should be considered a fundamentally different entity, primarily because of its potential for systemic metastasis that in situ lesions do not theoretically have. There are still many outstanding issues and dilemmas to be resolved by scientific investigation before the intriguing potential of these early forms of breast malignancy are fully understood.
Conservative surgery for the management of invasive and noninvasive carcinoma of the breast: NSABP trials
Authors: Fisher Bernard , Anderson Stewart
Published: December 2004

In 1976 the National Surgical Adjuvant Breast and Bowel Project (NSABP) initiated a randomized trial (B‐06) to evaluate the worth of lumpectomy in the treatment of patients with stages I and II breast cancer. This report presents, for the first time, findings from that trial through 10 years of follow‐up relative to ipsilateral breast tumor recurrence (IBTR), distant disease‐free survival, and survival of patients who were treated by modified radical mastectomy, lumpectomy, or lumpectomy followed by breast irradiation. The report indicates that the incidence of IBTR observed in the B‐06 trial is decreased by effective systemic therapy as well. Also commented on are a number of issues regarding the use of lumpectomy that are of concern to clinicians. They relate to the need for tumor specimen margins, the size of tumors amenable to lumpectomy, treatment of breast tumor recurrence, lumpectomy in older women, and other concerns. No patient or tumor characteristics have been identified that preclude the use of lumpectomy and radiation therapy. All evidence continues to justify the use of lumpectomy and breast irradiation for the treatment of invasive breast cancer. In addition, we have noted findings that indicate the propriety of lumpectomy and breast irradiation for treatment of localized ductal carcinoma in situ.
Extensor Mechanism Laxity at the Metacarpophalangeal Joint as Identified by a New Provocative Test: Predisposition to Dislocation
Authors: SHINOHARA T. , NAKAMURA R. , SUZUKI M. , MAEDA N.
Published: December 2004

A tendon subluxation test was performed on the unaffected side in 13 patients with traumatic extensor tendon dislocation of the middle finger and on both middle fingers in 800 healthy controls to identify extensor mechanism laxity at the metacarpophalangeal joint. Ten of the 13 patients with dislocation had laxity of middle finger extensor tendon, compared with 174 of the 800 (22%) controls. The difference in these rates of extensor tendon laxity is significant ( P<0.0001), and suggests that extensor mechanism laxity at the metacarpophalangeal joint may predispose to traumatic extensor tendon dislocation.
Triple Discrete Fungus Balls of the Paranasal Sinuses
Authors: Chao Ting‐Kuang
Published: December 2004

Paranasal sinus fungus balls occur usually in single sinus, most frequently the maxillary sinus.1 Multisinus localization was found only 6% in the largest review of this disease entity.2 Even multiple sinuses involved, these sinuses were mostly contiguous. Bilateral involvement was rare in the literature.2–4 Nevertheless, there has never been a report of three discrete sinus fungus balls in the same patient. This report represents the first case of the paranasal sinus fungus balls presenting in triple discrete sinuses at once.
Neck Mass Due to Thrombosis of the Jugular Vein in Patients with Cancer
Authors: Martins Mamede Rui Celso , De Oliveira Resende E Almeida Kalysta , De Mello‐Filho Francisco Veríssimo
Published: December 2004

The hypothesis that jugular thrombosis (JT) may cause a mass in the cervical region is usually overlooked. The objective of the present study was to identify the characteristics of neck masses resulting from JT in cancer patients and to analyze the possible reasons for their formation. A retrospective study was conducted on 8 patients with JT affected by 3 types of neoplasia, ie, carcinomas (3 cases), adenocarcinomas (3 cases), and lymphomas (2 cases) located in the breast, digestive apparatus, lymphatic system (2 cases each), lung and an undetermined site (1 case each), diagnosed over the last 12 years. The most frequent symptom of JT was the presence of a mass in the supraclavicular space (62.5% of cases) deeply located on the anterior margin of the sternocleidomastoid muscle and diagnosed by computed tomography and ultrasound. The masses were slightly hardened, with a clearly defined upper limit and an imprecise lower limit and with an irregular surface. The patients also presented with cough, hoarseness, pain during movements, facial edema, and collateral circulation. In one of the patients with a lung cancer, JT symptoms preceded the symptoms of cancer by 2 months. Hypercoagulation, compression, and invasion of a vessel possibly explain the occurrence of JT in these patients.
Changes in Programming over Time in Postmeningitis Cochlear Implant Users
Authors: Eshraghi Adrien A. , Telischi Fred F. , Hodges Annelle V. , Odabasi Onur , Balkany Thomas J.
Published: December 2004

OBJECTIVE

Although successful cochlear implantation of patients with deafness following meningitis is expected, long‐term stability of electrical current requirements has not been systematically evaluated. This study evaluated changes in programming for patients deafened by bacterial meningitis and stability of auditory performance over time.

STUDY DESIGN AND SETTING

In this retrospective descriptive study, cochlear implant (CI) stimulation mode and performance of 14 patients deafened by meningitis were compared with those of an age‐matched control group of patients deafened by other causes.

RESULTS

There were no significant differences in mean performance between the meningitis group and control group (P > 0.05). However, the postmeningitis group required progressively higher stimulation levels and higher programming modes over time as compared to the control group.

CONCLUSIONS

Even with deafness accompanied by labyrinthine ossification attributed to meningitis, neural elements were present and could be stimulated. Because increasing levels of stimulation were required over time, postmeningitic children with CIs, and those with cochlear ossification in particular, may need frequent programming adjustments to maintain performance.

SIGNIFICANCE

These patients need close follow‐up of stimulation levels and programming modes post‐operatively in order to perform optimally with CIs. EBM rating: B‐3.
Age‐Related Histopathologic Changes in the Human Cochlea: A Temporal Bone Study
Authors: Kusunoki Takeshi , Cureoglu Sebahattin , Schachern Patricia A. , Baba Kazuyasu , Kariya Shin , Paparella Michael M.
Published: December 2004

OBJECTIVES

Previous reports on aging of human cochlea included subjects with ear diseases or ototoxic drugs. We studied spiral ganglion cells, hair cells, and lateral wall of cochlea from subjects without ear disease or ototoxic drugs.

STUDY DESIGN

This study included 39 temporal bones from 24 subjects aged 1 day to 86 years. We assessed standard cytocochleograms, mean loss of fibrocytes in spiral ligament, and areas of stria vascularis.

RESULTS

Losses of outer hair cells and fibrocytes were significantly greater in childern, adults, and the elderly compared with infants. Spiral ganglion cell loss was significantly greater in adults and elderly compared with infants and children. Areas of stria vascularis of infants were significantly larger than the elderly.

CONCLUSIONS

Degenerative changes of outer hair cells occur in children but spiral ganglion cells remain the same until around 20 years. Degeneration of stria vascularis due to aging appears to be slower than spiral ligament. EBM rating: C.
Radial Forearm Free Tissue Transfer Reduces Complications in Salvage Skull Base Surgery
Authors: Chepeha Douglas B. , Wang Steven J. , Marentette Lawrence J. , Thompson Byron G. , Prince Mark E. , Teknos Theodoros N.
Published: December 2004

OBJECTIVE

Patients who undergo skull base resection after prior surgery or radiation may be at high risk for complications when local flaps alone are used for reconstruction. To determine whether the complication rate could be reduced, fasciocutaneous free tissue transfer was used to reinforce the dural closure in patients who had prior skull base surgery or radiation.

METHODS

This study is a case series of 20 patients (14 males, 6 females, aged 8–79 years of age with a mean of 47.7 years) from 1997 to 2001 who had prior skull base surgery or radiation, and underwent salvage skull base resection without large volume defects. All patients had a radial forearm free tissue transfer to reinforce the dural closure. Six patients had an osseous component to the forearm flap to provide vascularized bone to the orbital rim.

RESULTS

The overall local complication rate was 35%. Three patients (15%) had major complications including 1 case of meningitis, 1 case of cerebrospinal fluid leak, and 1 case of a flap requiring venous salvage. There were no flap failures, 1 idiopathic median nerve palsy, and no pathologic radius bone fractures.

CONCLUSION

Reconstruction with fasciocutaneous free tissue transfer for high‐risk patients with low‐volume dural defects following skull base resection can minimize the risk of major postoperative complications. EBM rating: C.
Adenoid Cystic Carcinoma of the Submandibular Gland: A 35‐Year Review
Authors: Cohen Alen N. , Damrose Edward J. , Huang Robert Y. , Nelson Scott D. , Blackwell Keith E. , Calcaterra Thomas C.
Published: December 2004

OBJECTIVES

To evaluate the treatment results of adenoid cystic carcinoma (ACC) of the submandibular gland at a single institution during a 35‐year period.

STUDY DESIGN & SETTING

A retrospective review was performed by examining the records and reviewing the pathology of 22 patients with ACC of the submandibular gland treated at UCLA Medical Center from June 1963 to December 1997.

RESULTS

Seven men and 15 women with an age range of 23 to 85 years (median, 48 years) were treated. Surgical intervention was performed in 21 patients. All patients with advanced tumor size, perineural invasion, microscopically positive surgical margins, or regional neck metastases received postoperative adjunctive therapy, primarily radiotherapy. Follow‐up varied from 6 months to 181 months (median, 67 months). Disease‐free survival at 3, 5, and 10 years was 66%, 57%, and 41% respectively, whereas overall survival was 76%, 70%, and 37%, respectively (note: 5‐ and 10‐year survival rates are not statistically conclusive due to the small sample size).

CONCLUSIONS

We report fairly high disease‐free survival rates in this patient population and a number of prognostic trends are evident. Early diagnosis, wide surgical intervention, and postoperative radiation are associated with a favorable prognosis. Advanced tumor size, positive surgical margins, perineural invasion, and local recurrence of the tumor are associated with an unfavorable prognosis. EBM rating: C.
Salvage of Partial Facial Soft Tissue Avulsions with Medicinal Leeches
Authors: Frodel John L. , Barth Patrick , Wagner Jon
Published: December 2004

BACKGROUND

Medicinal leeches have been demonstrated to be extremely useful and safe in the salvage of venous outflow compromised tissue, particularly in digit replants and various forms of flaps.

OBJECTIVE

To demonstrate the utility of medicinal leeches in the salvage of venous outflow‐compromised traumatic soft tissue avulsions in key facial structures.

METHODS

A retrospective review of 4 cases involving the external ear, nose, lip, and scalp in which apparent venous outflow compromise was present. Medicinal leeches were applied acutely in each of these 4 cases, salvaging each of the partially avulsed soft tissue segments.

RESULTS

Complete or near complete salvage of each soft tissue segment after using medicinal leeches.

CONCLUSIONS

Although it is unusual for a partial soft tissue avulsion of the face to require medicinal leech therapy, situations may occur in which there is adequate arterial inflow but inadequate venous outflow. In such cases, medicinal leeches may play a very important role in salvaging the soft tissue segment. This is particularly important in vital structures such as the ear, nose, lip, and eyelid in which acute or secondary reconstruction is complex. EBM rating: C.
Diagnosis of Middle Ear Disease using Tympanograms and Digital Imaging
Authors: Aronzon Anna , Ross Adam T. , Kazahaya Ken , Ishii Masaru
Published: December 2004

OBJECTIVE

The study investigates the ability of physicians with different levels of training to accurately identify middle ear (ME) pathology using tympanograms and tympanic membrane (TM) digital photographs.

STUDY DESIGN AND SETTING

Groups of medical students, internal medicine residents, and attending and resident otolaryngologists were presented with a set of 50 matched tympanograms and photographs of TMs. The physicians were asked to differentiate between a normal and an abnormal‐appearing TM. The sensitivity and specificity of diagnosis of ME pathology by physicians were compared with the gold standard, examining the ME cavity for pathology during myringotomy.

RESULTS

The sensitivity did not vary among physicians with different levels of training; however, specificity improved with an increase in physician experience.

CONCLUSIONS AND SIGNIFICANCE

This study establishes a baseline for accuracy of diagnosis of ME pathology using tympanograms and photographs of TMs as compared with binocular otomicroscopy and the gold standard, myringotomy. EBM rating: B‐2.
Software‐Enabled CT Analysis of Optic Nerve Position and Paranasal Sinus Pneumatization Patterns
Authors: Batra Pete S. , Citardi Martin J. , Gallivan Ryan P. , Roh Hwan‐Jung , Lanza Donald C.
Published: December 2004

OBJECTIVE

Delineate the relationships among the optic nerve (CN II), the sphenoid sinus, and the sphenoethmoid cell.

STUDY DESIGN

High‐resolution CT scans of 64 frozen human cadavers were obtained on a Siemens VolumeZoom CT scanner (Munich, Germany) and transferred to a CBYON Suite Doctor Station version 2.6 (CBYON, Mountain View CA) for standardized review.

RESULTS

Pneumatization around CN II was categorized into 5 types: no adjacent pneumatization (type 0), pneumatization adjacent to CN II (type 1), adjacent pneumatization with indentation (type 2), pneumatization of <50% CN II circumference (type 3), and pneumatization of >50% CN II circumference (type 4). The prevalence of types 0 to 4 CN II position relative to the sphenoid sinus was 4.7%, 25.8%, 39.8%, 14.1%, and 15.6%, respectively. The prevalence of sphenoethmoid cells was 28.1%. The prevalences of types 0, 1, 2, 3, and 4 CN II positions relative to the sphenoethmoid cell was 5.6%, 58.3%, 25%, 2.8%, and 8.3% respectively.

CONCLUSIONS

Software‐enabled CT review facilitated precise study of the anatomic relationships of CN II. Caution must be exercised during sinonasal surgery to minimize the risk of inadvertent CN II injury. EBM rating: D.
A Comparison of Polysomnography and a Portable Home Sleep Study in the Diagnosis of Obstructive Sleep Apnea Syndrome
Authors: Su Stephanie , Baroody Fuad M. , Kohrman Michael , Suskind Dana
Published: December 2004

OBJECTIVE

To validate the role of a portable sleep monitor device (SNAP) in the diagnosis of obstructive sleep apnea syndrome (OSAS). Inter‐reader variability was also assessed for both PSG and SNAP.

STUDY DESIGN AND SETTING

Sixty consecutive adults referred for PSG at The University of Chicago Sleep Disorder Clinic were prospectively enrolled.

RESULTS

There was no significant difference between total number of apnea and hypopnea, respiratory disturbance index (RDI), and minimum oxygen obtained by PSG and SNAP, but there was a significant difference between sleep time and mean oxygen. Pearson's correlation coefficient for RDI ≥ 15 was 0.92.

CONCLUSION

There was a significant correlation of RDIs between SNAP and PSG. SNAP has good sensitivity, specificity, positive and negative predictive values. Differences between SNAP and PSG could be attributed to inter‐reader variability and not necessarily due to technical limitations of SNAP. SNAP is an excellent tool for the diagnosis of OSAS in the laboratory setting. Future studies should be performed to evaluate SNAP's accuracy in the home setting in the diagnosis of OSAS. EBM rating: B‐2. (Otolaryngol Head Neck Surg 2004;131:844–50.)
High‐Frequency Ultrasound in the Measurement of Pediatric Craniofacial Integrity
Authors: Knott P. Daniel , Hazony Dov , Karafa Matthew , Koltai Peter J.
Published: December 2004

OBJECTIVE

This study evaluates the use of high‐frequency ultrasound in the measurement of the material nature of the pediatric craniofacial skeleton.

STUDY DESIGN AND SETTING

Three desiccated human skulls, aged 1 year, 5 years, and adult, underwent ultrasonic evaluation at 6 sites on each hemicranium.

RESULTS

The overall mean signal reflection coefficients for the infant, child, and adult skulls are 98.8 mV (13.75 mV SD), 172mV (24.5 mV SD), and 230 mV (23.5 mV SD), respectively. The mean signal reflection coefficient is positively correlated with increasing chronological age. Comparison of intra‐subject signal patterns suggests bone density fields, which vary as a function of growth.

CONCLUSION

High‐frequency ultrasound provides accurate measurements of the osseous impedance of the craniofacial skeleton. Pattern analysis suggests increases in skull density with greater growth and age.

SIGNIFICANCE

Although further testing must be performed in vivo, high‐frequency ultrasound may accurately measure the osseous impedance of the pediatric craniofacial skeleton. EBM rating: C.
Paleoenvironment of the Folsom archaeological site, New Mexico, USA, approximately 10,500 14C yr B.P. as inferred from the stable isotope composition of fossil land snail shells
Authors: Balakrishnan Meena , Yapp Crayton J. , Meltzer David J. , Theler James L.
Published: December 2004

Well-preserved aragonitic land snail shells (Vallonia) from late Pleistocene Eolian sediment in the Folsom archaeological site in New Mexico exhibit an overall decrease of δ18OPDB from maximum values of +2.7‰ (more positive than modern) to younger samples with lower average values of about −3.6‰ (within the modern range). The age of the samples (approximately 10,500 14C yr B.P.) suggests that the decrease in δ18O may manifest climatic changes associated with the Younger Dryas. Some combination of increased relative humidity and cooler temperatures with decreased δ18O of precipitation during the times of snail activity can explain the decrease in shell δ18O. A well-known Paleoindian bison kill occurred at the Folsom site during this inferred environmental transition.

Average δ13C values of the aragonite shells of the fossil Vallonia range from −7.3 to −6.0‰ among different archaeological levels and are not as negative as modern values. This suggests that the proportion of C4 vegetation at the Folsom site approximately 10,500 14C yr B.P. was greater than at present; a result which is consistent with other evidence for higher proportions of C4 plants in the region at that time.
A COMPARATIVE HISTORICAL STUDY OF THE CENSUS REGISTERS OF EARLY CHOSON KOREA AND MING CHINA
Authors: Rhee Younghoon
Published: December 2004

A comparison of Choson census registers from Sanŭm-hyon and Ming census registers from Huizhou clearly reveal structural differences between the two regarding the state and society. The main focii for comparison are relations between household and family, status of household members, the existence (or not) of a slave status such as nobi, the administrative structure for compiling the registers, and, through them, the characteristics of how the state governed the farming class. The study shows that during the Choson period, farmers were awarded tasks and duties (chik'yok) on an individual basis by the state, through which their social status was determined. Many of the farmers were nobi, enslaved men and women working either for the state or for yangban and government officials. The structure of the household between individual families was not necessarily uniform; an internal two-strata structure of chuho and hyopho is evident, higher and lower status households. State rule of the farming communities also showed a dual structure, with household members and land separated. It is very clear that inevitably the state governed only indirectly, through local petty officials of the “local scribe” (hyangni) class. Not only did these aspects not exist in contemporary Ming society but even in comparison with pre-Song history, Choson society exhibited special structural characteristics, in that it was not a centralized bureaucratic state like that which developed in the Ming.
Quantifying the effects of CO2‐fertilized vegetation on future global climate and carbon dynamics
Authors: Thompson Starley L. , Govindasamy Bala , Mirin Art , Caldeira Ken , Delire Christine , Milovich Jose , Wickett Mike , Erickson David
Published: December 2004

Climate and the global carbon cycle are a tightly coupled system where changes in climate affect exchange of atmospheric CO2 with the land biosphere and the ocean, and vice‐versa. In particular, the response of the land biosphere to the ongoing increase in atmospheric CO2 is not well understood. To evaluate the approximate upper and lower limits of land carbon uptake, we perform simulations using a comprehensive climate‐carbon model. In one case the land biosphere is vigorously fertilized by added CO2 and sequesters carbon throughout the 21st century. In a second case, CO2 fertilization saturates in year 2000; here the land becomes an additional source of CO2 by 2050. The predicted atmospheric CO2 concentration at year 2100 differs by 40% between the two cases. We show that current uncertainties preclude determination of whether the land biosphere will amplify or damp atmospheric CO2 increases by the end of the century.
Tracking the sea‐level signature of the 8.2 ka cooling event: New constraints from the Mississippi Delta
Authors: Törnqvist Torbjörn E. , Bick Scott J. , González Juan L. , van der Borg Klaas , de Jong Arie F. M.
Published: December 2004

The ever increasing need for accurate predictions of global environmental change under greenhouse conditions has sparked immense interest in an abrupt, century‐scale cooling around 8200 years ago, with a focal point in the North Atlantic and with hemispheric teleconnections. Despite considerable progress in the unraveling of this striking feature, including a conceivable driving mechanism (rapid drainage of proglacial Lake Agassiz/Ojibway and a resulting reduced strength of North Atlantic thermohaline circulation), several key questions remain unanswered. One salient aspect concerns the total amount of freshwater released during this catastrophic event, likely echoed by a near‐instantaneous eustatic sea‐level rise. So far, no attempts have been made to perform high‐resolution sea‐level studies that explicitly focus on this critical time interval. Here, we present new data from the Mississippi Delta suggestive of abrupt sea‐level rise associated with the 8.2 ka event. However, the amount of sea‐level rise was likely less than ∼1.2 m, corresponding to a meltwater volume of less than ∼4.3 1014 m3; values lower than estimates used by several recent studies.
Closure evaluation of size‐resolved aerosol pH in the New England coastal atmosphere during summer
Authors: Keene William C. , Pszenny Alexander A. P. , Maben John R. , Stevenson Eric , Wall Andrew
Published: December 2004

During summer 2002, soluble trace gases, the ionic composition of size‐resolved aerosols, and meteorological conditions were measured from the National Oceanic and Atmospheric Administration ship Ronald H. Brown in coastal air along the eastern U.S. seaboard. Aerosol acidities were extrapolated from direct pH measurements in minimally diluted extracts and were also inferred from the measured phase partitioning and thermodynamic properties of HCl, HNO3, NH3, HCOOH, and CH3COOH. Median pHs for 0.75‐ through 25‐μm geometric mean diameter (GMD) size fractions based on direct measurements (2.6–3.9) were higher than those inferred from HCl partitioning (1.7–3.3). Phase disequilibria caused negative deviations in median pHs inferred from HNO3 partitioning with aerosol size fractions greater than 2.8‐μm GMD; pHs inferred for smaller size fractions (median values of 1.9–3.0) were similar to those based on HCl (median values of 1.5–3.0). The pHs inferred from NH3 partitioning were significantly lower than those estimated by other approaches; causes for this apparent bias are not known. The dominance of gas‐phase HCOOH and CH3COOH was generally consistent with predicted phase partitioning with acidic aerosols. Typically large diel excursions in most gases implied corresponding variability in aerosol acidity. The pHs inferred from maximum and minimum mixing ratios of gases over each aerosol sampling interval suggested median 12‐hour variations of ∼0.4–0.7 pH unit. Total acidity (Ht = H+ + undissociated acids) was greater than H+ by 1–2 orders of magnitude in all size fractions; most Ht was in the form of HSO4−.
Effects of vegetation canopy processes on snow surface energy and mass balances
Authors: Niu Guo‐Yue , Yang Zong‐Liang
Published: December 2004

This paper addresses the effects of canopy physical processes on snow mass and energy balances in boreal ecosystems. We incorporate new parameterizations of radiation transfer through the vegetation canopy, interception of snow by the vegetation canopy, and under‐canopy sensible heat transfer processes into the Versatile Integrator of Surface and Atmosphere (VISA) and test the model results against the Boreal Ecosystem‐Atmosphere Study (BOREAS) data observed at South Study Area, Old Jack Pine. A modified two‐stream radiation transfer scheme that accounts for the three‐dimensional geometry of vegetation accurately simulates the transferring of solar radiation through the vegetation canopy when the leaf and stem area index is reduced to match the observed. VISA produces higher‐than‐observed surface albedo in wintertime. Implementation of a snow interception model that explicitly describes the loading and unloading of snow and the melting and refreezing of snow on the canopy into VISA reduces the fractional snow cover on the canopy and the surface albedo. VISA overestimates the downward sensible heat fluxes from the canopy to the snow surface, which leads to earlier snow ablation and a shallower snowpack than the observed. Explicitly including a canopy heat storage term in the canopy energy balance equation decreases the spuriously large amplitude of the diurnal canopy temperature variation and reduces the excessive daytime sensible heat flux from the canopy downward to the snow surface. Sensitivity tests reveal that the turbulent sensible heat flux below the vegetation canopy strongly depends on the canopy absorption coefficient of momentum. During spring the daytime temperature difference between the snow surface and the vegetation canopy forms a strongly stable atmospheric condition, which results in a larger absorption coefficient of momentum and a weak turbulent sensible heat flux. The modeled excessive downward sensible heat flux from the vegetation canopy to the snow surface is considerably reduced through the stability correction to the canopy absorption coefficient of momentum.
Seasonal cycles of mixing ratio and 13C in atmospheric methane at Suva, Fiji
Authors: Lowe David C. , Koshy Kanayathu , Bromley Tony , Allan W. , Struthers H. , Mani F. , Maata M.
Published: December 2004

A series of clean air samples has been collected at a coastal site near Suva, Fiji (18°08′S, 178°26′E) by researchers at the University of the South Pacific. These samples, covering the period 1994 to mid‐2002, have been analyzed for methane mixing ratio and δ13C and provide the first ever time series of these species reported for this part of the tropical South Pacific. The data show large variability when compared to similar time series of the same species measured farther south in the extratropical Pacific. In particular, summer variability at the Fiji site is high, especially through La Niña conditions. A modeling study was carried out using a modified version of the UK Meteorological Office's Unified Model (a general circulation model) and TM2 (a chemical transport model driven by stored meteorological fields). These showed that a large amount of the variability in the methane mixing ratio and its δ13C can be attributed to complex tropical meteorology in the region changing the rate of transport of methane from the Northern into the Southern Hemispheres. Enhanced interhemispheric transport occurred during the summer months, especially during La Niña conditions which lead to the suppression of expected minima in the methane mixing ratio caused by OH oxidation. Although enriched signals in δ13C were expected at the site caused by intrusions of methane emitted from tropical biomass burning in Indonesia, relatively few of these events could be identified in the time series.
Impact crater air fall deposits on the surface of Venus: Areal distribution, estimated thickness, recognition in surface panoramas, and implications for provenance of sampled surface materials
Authors: Basilevsky A. T. , Head J. W. , Abdrakhimov A. M.
Published: December 2004

During their formation, impact craters on Venus larger than 11 km in diameter acquired parabolic features composed of air fall deposits that are radar‐dark in Magellan synthetic aperture radar images. A model of the parabola planimetric shape and size (the latter being a function of crater diameter) was constructed from the data of Campbell et al. [1992]. Reconstructing model parabolas around all impact craters with D > 11 km in the regions of the Venera‐Vega sites revealed that parabolas cover 80–90% of the surface. These regions are representative of the majority of the Venus surface in terms of general geology and impact crater abundance. This implies that a very significant part of the surface of Venus was covered at least once with parabola deposits, and thus it is logical to look for them in the TV panoramas of the Venus surface taken by the Venera landers. These panoramas show the presence of soil and layered rocks, with the rocks (shown by the data of several instruments) consisting of porous, mechanically weak material, implying an altered or sedimentary (in a broad sense, including volcanic tuffs and impact deposits) nature. We propose the hypothesis that (1) the layered rocks may be the partly lithified and then partially eroded parabola deposits, while (2) the soil may partly be unlithified crater deposits and partly a product of the degradation of layered rocks. If this hypothesis is correct, then the interpretations related to the provenance of the materials studied geochemically by the landers may need revision. In particular, it is very possible that deep‐seated (>1–3 km) rocks (the lower units of the regional plains complex, rocks of the plains basement, and plutonic rocks) are a part (perhaps significant) of the material analyzed by the landers. The possible presence of this deeply derived material should also be taken into account in selecting landing sites for future missions to Venus.
Corrigendum to noncompetitive antagonism of BIBN4096BS on CGRP‐induced responses in human subcutaneous arteries
Authors: Sheykhzade Majid , Lind Henrik , Edvinsson Lars
Published: December 2004

British Journal of Pharmacology (2004) 143, 1076. doi:10.1038/sj.bjp.0706085
Novel function of the flap endonuclease 1 complex in processing stalled DNA replication forks
Authors: Zheng Li , Zhou Mian , Chai Qing , Parrish Jay , Xue Ding , Patrick Steve M , Turchi John J , Yannone Steven M , Chen David , Shen Binghui
Published: December 2004

Restarting stalled replication forks partly depends on the break‐induced recombination pathway, in which a DNA double‐stranded break (DSB) is created on the stalled replication fork to initiate the downstream recombination cascades. Single‐stranded DNA gaps accumulating on stalled replication forks are potential targets for endonucleases to generate DSBs. However, it is unclear how this process is executed and which nucleases are involved in eukaryotic cells. Here, we identify a novel gap endonuclease (GEN) activity of human flap endonuclease 1 (FEN‐1), critical in resolving stalled replication fork. In response to replication arrest, FEN‐1 interacts specifically with Werner syndrome protein for efficient fork cleavage. Replication protein A facilitates FEN‐1 interaction with DNA bubble structures. Human FEN‐1, but not the GEN‐deficient mutant, E178A, was shown to rescue the defect in resistance to UV and camptothecin in a yeast FEN‐1 null mutant.
Where firms change: internal development versus external capability sourcing in the global telecommunications industry
Authors: Capron Laurence , Mitchell Will
Published: December 2004

Abstract This paper studies firms' choices of internal vs external sources of new capabilities. We first compare transaction cost, knowledge‐based, and institutional arguments, which all emphasize the attributes of capabilities, including contractual hazards, capability gaps, and legitimacy. We next contrast these arguments with propositions that emphasize constraints on external availability as drivers of internal development. We then propose that a firm's internal reconfiguration and external reconfiguration routines affect its capability sourcing decisions as interactions with the capability attributes and external constraints. The empirical analysis draws on a survey of 162 telecommunications firms operating in Europe, North America, Latin America, or Asia.
A longitudinal study comparing the effort - reward imbalance and demand - control models using objective measures of physician utilization
Authors: Ostry Alec S. , Hershler Ruth , Chen Lisa , Hertzman Clyde
Published: December 2004

Background: The objectives of this study were to compare the predictive validity of the demand - control and effort - reward imbalance models using objective measures of physician utilization. Methods: Self-reports for psychosocial work conditions were obtained in interviews with 1,028 workers using the demand - control and effort - reward imbalance models. Physician utilization outcomes were obtained through linkage to the British Columbia Linked Health Database. Outcomes were any visit to a physician for mental health reasons and 30 or more physician visits for any reason. The predictive validity of both models was compared in a longitudinal study using logistic regression. Results: Neither job strain nor effort - reward imbalance predicted either outcome. However, low esteem reward and low status control increased the risk for 30 or more physician visits by, respectively, approximately 60% and 30%. Conclusions: In a sample of middle-aged blue-collar current and ex-sawmill workers in Western Canada, followed prospectively, after controlling for sociodemographic and workplace confounders, and reducing the potential for adverse health selection into high-stress jobs, low esteem reward and low status control were associated with a significantly greater risk for 30 or more physician visits for any reason.