bluuebunny/crossref_metadata_2025_split huggingface dataset:
A model for low‐energy thick‐target bremsstrahlung produced in a scanning electron microscope
Authors: Semaan Mars , Quarles C. A. 
Published: August 2002

AbstractThick‐target bremsstrahlung measurements were obtained for various atomic numbers and for energies between 10 and 25 keV. A Jeol JSM 6100 scanning electron microscope was used for the electron beam and a Oxford Instruments Link Si(Li) detector for the bremsstrahlung spectrum. The experimental data were compared with a model that computes the thick‐target bremsstrahlung spectrum by integrating the tabulated relativistic partial‐wave doubly differential cross‐section for thin‐target bremsstrahlung over the target taking electron energy loss into account in the continuous slowing down approximation. The model corrects for electron backscattering, x‐ray attenuation in the target and the efficiency of the x‐ray detector. Very good agreement was found between the model and the experimental results. Extension of the model to consider multiple scattering in the target is also discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Human pancreatic glucokinase (GlkB) complements the glucose signalling defect of Saccharomyces cerevisiae hxk2 mutants
Authors: Mayordomo Isabel , Sanz Pascual 
Published: August 2002

AbstractHuman pancreatic glucokinase (GlkB, hexokinase IV) has been expressed in Saccharomyces cerevisiae. The recombinant protein showed similar enzyme kinetics to those described for the original enzyme. When expressed in hxk2 yeast mutants, GlkB complemented both the glucose induction and the glucose repression defects present in the mutant. It was also functional in regulating the activity of the Snf1 kinase complex in response to glucose, participating in the regulation of the Reg1/Glc7 phosphatase complex, as its yeast counterpart. Copyright © 2001 John Wiley & Sons, Ltd.
Historic Landmarks in Clinical Transplantation: Conclusions from the Consensus Conference at the University of California, Los Angeles
Authors: Groth Carl G. , Brent Leslie B. , Calne Roy Y. , Dausset Jean B. , Good Robert A. , Murray Joseph E. , Shumway Norman E. , Schwartz Robert S. , Starzl Thomas E. , Terasaki Paul I. , Thomas E. Donnall , van Rood Jon J. 
Published: August 2002

Abstract.The transplantation of organs, cells, and tissues has burgeoned during the last quarter century, with the development of multiple new specialty fields. However, the basic principles that made this possible were established over a three‐decade period, beginning during World War II and ending in 1974. At the historical consensus conference held at UCLA in March 1999, 11 early workers in the basic science or clinical practice of transplantation (or both) reached agreement on the most significant contributions of this era that ultimately made transplantation the robust clinical discipline it is today. These discoveries and achievements are summarized here in six tables and annotated with references.
Medullary Carcinoma of the Thyroid Gland
Authors: Wells Samuel A. , Franz Claudia 
Published: August 2002

AbstractMedullary thyroid carcinoma (MTC) is an uncommon thyroid tumor that has attracted a great deal of interest because of its frequent presentation as a familial tumor and its primary involvement in the type II multiple endocrine neoplasia (MEN) syndromes MEN‐IIA and MEN‐IIB and familial medullary thyroid carcinoma (FMTC). The MTC tumor cells secrete the polypeptide hormone calcitonin, which serves as an excellent tumor marker, useful for defining the presence of disease, preoperatively or following thyroidectomy. The discovery that mutations in the RET proto‐oncogene are associated with MEN‐II syndromes was highly significant in that it demonstrated a clear correlation between genotype and phenotype; and most importantly it provided a mechanism whereby family members at risk could be identified by direct DNA analysis. Virtually all patients with MEN‐IIA, MEN‐IIB, and FMTC develop MTC; therefore there is a clear rationale for performing thyroidectomy as soon as a RET mutation has been identified. Because MTC appears to be much more aggressive in patients with MEN‐IIB, thyroidectomy is performed during the first year of life in this setting, whereas in patients with MEN‐IIA, where the tumor appears to be more indolent, the procedure can be safety delayed until age 5 years. Reoperative neck exploration in patients with evidence of persistent or recurrent MTC has been effective in a significant number of patients, although the success of the operation requires careful patient selection and preoperative assessment. MTC, as expressed in the MEN‐II syndromes, is an excellent model to evaluate the usefulness of interventional therapy in patients demonstrated to have a genetic predisposition for cancer.
Benefits of Endoscopic Vein Harvesting
Authors: Marty Bettina , von Segesser Ludwig Karl , Tozzi Piergiorgio , Guzmann Juan , Frascarolo Philippe , Muller Xavier , Hayoz Daniel 
Published: August 2002

AbstractThe purpose of this study was to evaluate and compare the benefits of endoscopic saphenous vein harvesting (EVH) with the traditional incision technique (TIT) for coronary artery bypass grafting (CABG) in respect to the technical procedure and clinical outcome. In a prospective nonrandomized, case‐matched study the greater saphenous vein was harvested for CABG in 22 patients using the endoscopic technique and in 18 patients with the traditional method. Comparisons were made for the operating time, length of incision and vein harvested, graft quality, postoperative complications, and pain assessment. Patient demographics were well matched. EVH required smaller incisions than did the TIT (10.5 ± 6.6 vs. 31.2 ± 7.8 cm, respectively; p < 0.0001). Harvest time and vein quality were comparable in the two groups. Total vein operating time was shorter following the endoscopic technique (60 ± 24 vs. 100 ± 35 minutes, respectively; p < 0.0001). EVH had fewer complications (NS), and postoperative pain was significantly less (p= 0.0034). The major advantages of endoscopic vein harvesting are a significant reduction of postoperative pain and strikingly better cosmetic results. Wound complications seem to be less frequent.
Supernumerary Parathyroid Glands: Frequency and Surgical Significance in Treatment of Renal Hyperparathyroidism
Authors: Pattou François N. , Pellissier Laurent C. , Noël Christian , Wambergue François , Huglo Damien G. , Proye Charles A.G. 
Published: August 2002

AbstractSupernumerary parathyroid glands (SPGs) are found in 13% of random autopsies. The high incidence of SPGs could explain the persistence or trigger recurrence of renal hyperparathyroidism after surgery. The aim of this study was to assess the frequency and clinical relevance of SPG in patients operated on for renal hyperparathyroidism (HPT). In this retrospective study we reviewed the medical records of 290 patients with renal HPT who were initially treated in our department. We examined the anatomic and pathologic findings during cervical surgical exploration and the outcome of HPT during follow‐up. SPGs were identified in 87 patients (30%) during the initial cervicotomy, corresponding to intrathymic parathyroid cell islets (one to four) in 70 cases and to extrathymic SPG in 17 patients. Among 260 patients available for follow‐up, 11 experienced persistent HPT (4%), and 34 developed recurrent HPT (13%). A total of 25 patients were reoperated on, and SPGs were responsible for 4 of 8 cases of persistent HPT and 4 of 17 cases of recurrent HPT, representing an overall frequency of 32%. The anatomic distribution of SPGs found during reoperations included thymus, retroesophageal grove, carotid sheath, and mediastinum. SPGs are thus present in 30% of patients with renal HPT and are situated mainly in the thymus. Thymectomy should be performed routinely during the first surgical exploration to prevent recurrences arising from anterior mediastinal glands. SPGs were also responsible for 32% of persistent or recurrent HPT. In that setting, frankly ectopic SPGs are not rare, and preoperative imaging appears highly desirable prior to embarking on surgical reexploration.
Anatomic Dissociation between the Intrahepatic Bile Duct and Portal Vein: Risk Factors for Left Hepatectomy
Authors: Cheng Yu Fan , Huang Tung Liang , Chen Chao Long , Sheen‐Chen Shyr Ming , Lui Chun Chung , Chen Tai Yi , Lee Tze Yu 
Published: August 2002

AbstractThe anatomic variations of the intrahepatic portal vein and bile duct were analyzed to evaluate the potential risk of left hepatectomy. A total of 210 cholangiograms and hepatic arterioportograms were performed in which the ramifications of the intrahepatic portal vein and bile duct were investigated. The orientation of the intrahepatic duct and portal vein were classified into five types. In 175 patients (83.33%), the intrahepatic portal vein and bile duct had the same anatomic classification. In 24 patients (11.43%), the right anterior or posterior intrahepatic duct drained into the left hepatic duct at the umbilical portion (type IV); there were only 15 patients (7.14%) whose portal veins fell into this category. All patients with type IV portal veins had type IV hepatic ducts, but there were 9/49 patients (18.36%) whose hepatic duct distribution belonged to type IV but their portal veins belonged to type II (6 cases) or III (3 cases). Without complete knowledge of the intrahepatic portal and biliary anatomy, insufficient portal perfusion and bile duct complications may result from the left hepatectomy operation. Preoperative portal vein evaluation or left portal vein clamping can provide significant information, but there are still 18.36% of patients where type IV biliary ducts were not detected in those with type II and III portal veins. Cholangiography is of paramount importance in these two groups of patients, as it can prevent inadvertent injury to the right intrahepatic ducts, which drain into the left intrahepatic duct. On the other hand, intraoperative ultrasonography is recommended to identify or exclude an aberrant portal vein if type VI biliary anatomy is detected during intraoperative cholangiography.
Close Correlation between Increased Sialyl‐Lewisx Expression and Metastasis in Human Gastric Carcinoma
Authors: Ura Hideki , Denno Ryuichi , Hirata Koichi , Yamaguchi Koji , Yasoshima Takahiro , Shishido Takayuki 
Published: August 2002

AbstractExpression of sialyl‐Lewisx
(sLex) antigen was studied immunohistochemically in 110 resected human gastric carcinomas using an anti‐sLex
monoclonal antibody. Lymph node, liver, and peritoneal metastases were clearly more prevalent in tumors expressing high levels of sLex than in those with no or low‐level sLex
expression. No correlation was found between sLex
expression and histologic grade or histologic type of the Lauren classification. Among the tumors with lymph node metastasis, 44%
expressed high levels of sLex in both the primary tumor and involved lymph nodes, and 14% of the metastatic lesions demonstrated increased sLex expression. The 5‐year survival rate of the patients undergoing complete (R0) gastric resections was 60% in the sLex high‐expression group, which was significantly lower than that of the sLex low‐expression group (81%) and of the no‐expression group (87%) (p < 0.05). These results suggest that high‐level sLex expression is related to both an increased risk of metastasis and poor prognosis in gastric cancer patients.
Increased Serum Interleukin‐8: Correlation with Poor Prognosis in Patients with Postoperative Multiple Organ Failure
Authors: Hamano Kimikazu , Gohra Hidenori , Noda Hiroshi , Katoh Tomoe , Fujimura Yoshihiko , Zempo Nobuya , Esato Kensuke 
Published: August 2002

AbstractThis study investigated whether cytokines and colony‐stimulating factors can predict prognosis in patients with postoperative multiple organ failure (MOF). We evaluated 14 patients with postoperative MOF who underwent operation for cardiovascular disease. Seven patients recovered from MOF (survivors) and seven did not recover and died (nonsurvivors). The white blood cell (WBC) count, granulocyte colony‐stimulating factor, monocytic colony‐stimulating factor, interleukin‐6 (IL‐6), and IL‐8 were measured on the day the patients were judged to be in MOF and each week thereafter until the patients recovered or died. Survivors and nonsurvivors were equivalent in terms of age, gender, proportion of use of extracorporeal circulation, operation time, volume of blood transfusion, time from operation to the onset of MOF, the MOF score, proportion of bacteremia, duration of MOF, and number of failed organs. The mean duration of MOF was less than 2 weeks in both groups; therefore the measurements were compared on the first day of MOF and 1 week later. No significant differences between the two groups in terms of WBC counts, colony‐stimulating factors, and IL‐6 levels were noted. However, the serum level of IL‐8 was significantly higher in nonsurvivors than in survivors. Patients with a high serum levels of IL‐8 at the time of MOF had a poor prognosis.
Issues in Surgical Randomized Controlled Trials
Authors: McLeod Robin S. 
Published: August 2002

Abstract.As technology expands and health care resources become more limited, there is increasing pressure on surgeons to evaluate surgical procedures and technology to ensure they are effective. No longer is evidence from case series acceptable, and treatments must be evaluated in randomized controlled trials. The power of the randomized controlled trial is that because of its rigorous design the risk of random or systematic (bias) error is minimized and thus the risk of making an incorrect conclusion about the efficacy of a treatment is minimized. The randomized controlled trial has been widely accepted for evaluating the efficacy of medical treatments but less so for surgical procedures. Many cite methodologic issues related to surgical issues as the reason for this, including concerns related to standardization of the surgical procedure, timing of surgical trials, difficulties with blinding of subjects and investigators, ethics of surgical trials, and patient and surgeon acceptance of surgical trials. These issues are discussed in this paper as are possible strategies to minimize their effect.
Tumors of the Esophagus
Authors: Hatch George F. , Wertheimer‐Hatch Laura , Hatch Kathryn F. , Davis Gregory B. , Blanchard D. Kay , Foster Roger S. , Skandalakis John E. 
Published: August 2002

Abstract.This collective review includes all available case reports of smooth muscle (stromal) tumors of the esophagus in the world literature. Compiling this review, we endeavored to examine cumulative and recently collected data of both benign and malignant esophageal smooth muscle tumors found in the literature spanning the period from 1875 to 1996, which totaled 1679 leiomyomas (LMs) and 165 leiomyosarcomas (LMSs). The peak age of occurrence of benign smooth muscle tumors in the esophagus was found to be between the ages of 30 and 59, whereas the highest frequency of malignant tumors was seen later in life, during the decade from age 60 to 69. The most common location of both LMs and LMSs was the lower third of the esophagus. Their patterns of growth differed; LMs were more likely to grow intramurally, and LMSs were predominantly intraluminal. Most patients with LMs presented with dysphagia and pain or discomfort; patients with LMSs additionally commonly complained of weight loss. As with smooth muscle tumors of other areas of the gastrointestinal tract, the duration of symptoms averaged 1 month to 1 year, and malignant tumors grew to larger sizes than benign neoplasms. Approximately one‐third of LMSs had metastasized at diagnosis, and there was a 5‐year survival rate of approximately 20%.
Rapid evolution of larval development time during mass‐rearing in the melon fly, Bactrocera cucurbitae
Authors: Miyatake Takahisa , Yamagishi Masaaki 
Published: August 2002

AbstractA quantitative genetic analysis of rapid evolution of a life history trait has been conducted on the first 24 generations of mass‐rearing in the melon fly Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). The phenotypic variance of larval development time in each generation was divided into genetic and residual components. Mean and phenotypic coefficients of variation of larval development time decreased gradually as generations proceeded as a result of artificial selection for shorter larval period in the mass‐rearing procedure. There was a trend that additive genetic coefficients of variation in larval development time decreased with generations. These changes are entirely attributed to genetic responses to laboratory selection under the mass‐rearing environment because the population was maintained at a very large size so as to exclude random genetic drift and inbreeding depression, which would be other factors responsible for the observed genetic changes. The residual coefficients of variation in larval development time did not change with generations. Realized heritability of larval development time was low. The heritabilities for larval development time estimated from parent–offspring regression at generations 60 and 70, when the evolutionary plateau was asymptotically reached, were not significantly larger than 0.
In Vitro Evaluation of Antibiotic Elution from Polymethylmethacrylate (PMMA) and Mechanical Assessment of Antibiotic‐PMMA Composites
Authors: Weisman Debra L. , Olmstead Marvin L. , Kowalski Joseph J. 
Published: August 2002

Objective—To determine whether different methods of sterilization of antibiotic vials or the heat of polymerization altered the antimicrobial activity or mechanical properties of antibiotic/polymethylmethacrylate (PMMA) composites when compared to antibiotic‐free PMMA.Study Design—In vitro study.Methods—Steam‐sterilized, gas‐sterilized, and non‐sterilized 1 gram vials of cefazolin and injectable gentamicin sulfate (high and low doses) were mixed with PMMA to prepare composites for antibiotic elution evaluation, compression, and elongation testing. Blocks of PMMA that contained antibiotic were assayed for antibacterial activity using an agar gel diffusion method or were placed in phosphate buffered saline (PBS) to assess elution of antibiotic. Phosphate buffered saline samples from steam‐sterilized cefazolin and high‐dose gentamicin groups were assayed on days 1, 2, 5, and 9 for cefazolin or gentamicin concentration by high‐pressure liquid chromatography or fluorescent polarization immunoassay, respectively.Results—Pmma blocks containing antibiotic inhibited bacterial growth of Staphylococus aureus 25923 for an average of 9 days. Cefazolin and gentamicin concentration in PBS decreased dramatically after the first 24 hours, but remained above minimum inhibitory concentration (MIC) throughout the experiment for all groups except low‐dose gentamicin. Compressive strength of plugs made from plain cement and plugs made from PMMA mixed with untreated and steam‐sterilized cefazolin was similar, but was significantly different from the other groups. There appeared to be an inverse relationship between compressive strength and elongation.Conclusion—PMMA/antibiotic composites inhibited bacterial growth for 7 to 10 days. Compressive strength was affected by different additions of antibiotic.Clinical Relevance—Bacteria introduced during a surgical procedure may be inhibited by elution of antibiotic from PMMA at the time of contamination.
Hemostatic Profiles in 39 Dogs With Congenital Portosystemic Shunts
Authors: Niles Jacqui D. , Williams John M. , Cripps Peter J. 
Published: August 2002

Objectives— To determine if there were significant changes in prothrombin time (PT), partial thromboplastin time (PTT), and fibrinogen levels in dogs with naturally occurring congenital portosystemic shunts (CPSS) and to determine if there was any association between these values, serum albumin concentration, and the ability to attenuate the shunt vessel.Study Design— Retrospective clinical study.Animals— Thirty‐nine client‐owned dogs.Methods— Medical records of 60 dogs with confirmed CPSS were retrospectively evaluated. Hemostatic profiles had been performed before surgery in 39 cases.Results— Dogs with CPSS had significantly higher values for PTT ( P < .001) when compared with normal dogs. Of the total number of dogs, 64.1% had a PTT greater than 16 seconds (25/39). PTT was prolonged by 25% or more in 51.3% of dogs (20/39). PT tended to be higher in dogs with CPSS (

P= .036), although only 7.7% (3/39) of dogs had a PT greater than 12 seconds (the maximum reference value). Dogs with CPSS had significantly lower values for albumin and fibrinogen (

P<.001). Platelet numbers were within the normal range in 87.2% of cases (34/39). Of the 5 dogs with platelet numbers outside the normal range, 3 were mildly thrombocytopenic. Fibrin degradation product concentrations were not elevated in any dogs tested (

N = 22). There was no significant difference in any of the measured variables between dogs with extrahepatic shunts and those with intrahepatic shunts (

P >.1). For PT, PTT, albumin, and fibrinogen, there was no significant difference between dogs that underwent total, partial, or no attenuation (

P > .3).Conclusions— Dogs with CPSS have a tendency to have a prolonged PTT. There was no significant difference in hemostatic profile results between dogs with intrahepatic shunts versus extrahepatic shunts. Preoperative hemostatic profile abnormalities were not useful as predictors of ability to attenuate CPSS.Clinical Relevance— Prolonged PTT was not associated with bleeding tendencies in any of the dogs. Assays of individual clotting factors may help to further characterize the abnormalities present in animals with CPSS and may identify specific factor deficiencies. This might enable identification of a noninvasive diagnostic or prognostic indicator.
Lutropin Receptor Function: Insights from Natural, Engineered, and Computer‐Simulated Mutations
Authors: Fanelli Francesca , Themmen Axel P. N. , Puett David 
Published: August 2002

AbstractThe lutropin receptor is a member of the superfamily of G protein‐coupled receptors and, in humans, binds two closely related ligands, members of the heterodimer glycoprotein hormone family. As reviewed herein, comparative analyses of natural, engineered, and computer‐simulated mutations of the lutropin receptor have provided considerable insight into the molecular basis of receptor function.
VEGF Receptor Signaling and Endothelial Function
Authors: Kliche Stefanie , Waltenberger Johannes 
Published: August 2002

AbstractAngiogenesis, the formation of new blood vessels from preexisting ones, is a central process during normal development and during pathological repair. Vascular endothelial growth factor‐A (VEGF‐A) can stimulate both physiological and pathological angiogensis. VEGF‐A is a ligand for the two receptor tyrosine kinases VEGFR‐1 (Flt‐1) and VEGFR‐2 (KDR/Flk‐1). Most biological functions of VEGF‐A are mediated via VEGFR‐2, whereas the role of VEGFR‐1 is largely unknown. Activation of mitogenactivated kinase, stress‐activated kinase, protein kinase C, and the Akt pathway are implicated in VEGF‐A‐dependent endothelial function, including cell survival, proliferation, generation of nitric oxide, and the induction of angiogenesis. Induction of metalloproteinases, activation of focal adhesion kinase and of PI3‐kinase are implicated in VEGF‐A‐induced endothelial cell migration. The important role of nitric oxide as a mediator of endothelial function in vivo links the receptor signaling network to other biological effects.