bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laparoscopic versus Open Appendectomy: Time to Decide
Authors: Fingerhut Abe , Millat Bertrand , Borrie Fredéric 
Published: August 2002

AbstractAlthough widely practiced, laparoscopic appendectomy (LA) has not met with universal approval. Several controlled trials have been conducted, some in favor, others not. The goal of this review was to ascertain (1) if laparoscopy was capable of improving the diagnostic and therapeutic difficulties encountered during open appendectomy (OA) and (2) if the introduction of laparoscopy in the overall management of acute appendicitis has changed anything in practice. Analysis and criticism of 17 controlled studies (nearly 1800 patients) on laparoscopic appendectomy and 2 randomized studies dealing with diagnostic laparoscopy are reported. Because of the questionable quality of randomized controlled trials (number of patients, exclusions, withdrawals, blinding, intention‐to‐treat analysis), publication biases, local practice variations (hospital stay, rate of enrollment), results regarding analgesia requirements, return to activity and work, duration of hospital stay, outcome, follow‐up, and antibiotic prophylaxis the studies must be interpreted with caution. The real world of appendicitis probably differs greatly from the atmosphere under which controlled trials comparing LA and OA have been performed. Statistical significance is contrary to the clinical significance of the results. Consistently longer operating times [the difference ranging from 8 minutes (NS) to 29 minutes (p < 0.0001)], a minimal reduction in hospital stay [0.1 day (NS) to 2.1 days (p < 0.007)], and, somewhat more controversial, an earlier return to normal activity were reported for LA. Data on analgesic requirements were confusing, but wound complications were more frequent after OA [pooled odds ratio for 10 studies: 2.6 (95% CI 1.3–5.2)]. Unsolved problems include national behavioral problems, age and experience of operating surgeons (LA or OA), and emergency conditions (availability of staff, instruments). Results of cost analysis vary according to the standpoint of disease, the patient, the surgeon, the treatment center, industry, and society. Three questions remain: Because of the competition of LA versus OA, OA has improved greatly. Can it be improved any more? Is there a place or need for further randomized controlled trials? Should we not conclude once and for all that LA is out?
Interleukin‐6 and Tumor Necrosis Factor‐α Levels following Hepatic Cryotherapy: Association with Volume and Duration of Freezing
Authors: Seifert Joachim K. , Stewart Graham J. , Hewitt Peter M. , Bolton Elaine J. , Junginger Theodor , Morris David L. 
Published: August 2002

Abstract.Although morbidity following cryotherapy is usually minor, a syndrome of multiorgan failure and disseminated intravascular coagulation (DIC) has been described and referred to as the cryoshock phenomenon. We hypothesized that mediators similar to those in septic shock may be involved in this syndrome. In this study we aimed to assess the plasma concentrations of the cytokines tumor necrosis factor‐α (TNF‐α) and interleukin‐6 (IL‐6) following hepatic cryotherapy and to relate them to the duration and volume of freezing and to hepatocellular injury. Between April and December 1997 blood samples were taken preoperatively and at different times postoperatively from patients undergoing hepatic artery catheter‐insertion (HAC) (n= 15), cryotherapy (n= 5), liver resection (n= 9), liver resection and edge cryotherapy (n= 7), or liver resection and cryotherapy of additional lesions (n= 9). They were analyzed for serum aspartate transaminase (AST) and plasma TNF‐α and IL‐6 levels. There was a significant association (Pearson correlation) of serum AST levels 1 hour postoperatively with plasma TNF‐α and IL‐6 levels at the end of the procedure. In patients undergoing cryotherapy or resection with cryotherapy of additional lesions (n= 14), the volume and duration of hepatic freezing were significantly associated with postoperative serum AST and plasma TNF‐α and IL‐6 levels at various postoperative times. Hepatic cryotherapy is followed by cytokine release, with postoperative plasma TNF‐α and IL‐6 levels associated with the degree of hepatic cryotrauma. These mediators may be involved in the occurrence of cryoshock following large‐volume hepatic freezing.
A comparison of species diversity estimators
Authors: Mouillot D. , Leprêtre Alain 
Published: August 2002

AbstractAlthough having been much criticized, diversity indices are still widely used in animal and plant ecology to evaluate, survey, and conserve ecosystems. It is possible to quantify biodiversity by using estimators for which statistical characteristics and performance are, as yet, poorly defined. In the present study, four of the most frequently used diversity indices were compared: the Shannon index, the Simpson index, the Camargo eveness index, and the Pielou regularity index. Comparisons were performed by simulating the Zipf–Mandelbrot parametric model and estimating three statistics of these indices, i.e., the relative bias, the coefficient of variation, and the relative root‐mean‐squared error. Analysis of variance was used to determine which of the factors contributed most to the observed variation in the four diversity estimators: abundance distribution model or sample size. The results have revealed that the Camargo eveness index tends to demonstrate a high bias and a large relative root‐mean‐squared error whereas the Simpson index is least biased and the Shannon index shows a smaller relative root‐mean‐squared error, regardless of the abundance distribution model used and even when sample size is small. Shannon and Pielou estimators are sensitive to changes in species abundance pattern and present a nonnegligible bias for small sample sizes (<1000 individuals).
Penile Amputation and Sheath Ablation in the Horse
Authors: Doles Jim , Williams John W. , Yarbrough Tom B. 
Published: August 2002

Objective— To report a surgical technique for penile amputation and sheath ablation in horses.Study Design— Retrospective study.Animals or Sample Population— Twenty‐five adult geldings of various breeds with conditions requiring penile amputation and sheath ablation.Methods— The medical records of horses that had penile amputation and sheath ablation were reviewed. Briefly, the technique involved en bloc resection of the skin and subcutaneous tissues of the inner and outer lamina of the prepuce and penile shaft. Resection of the penile shaft, proximal to diseased segments, and spatulation of the urethral mucosa was followed by fixation of the penis to the ventral abdomen and closure of the peripreputial skin over the ventral aspect of the penis and creation of a new mucocutaneous junction at the urethral orifice.Results— Mild to moderate postoperative hemorrhage occurred in all horses. Partial dehiscence of the mucocutaneous junction occurred in 8 horses; all healed by second intention. Postoperative pain lasting 24 to 48 hours occurred in 7 horses; 1 required epidural analgesia for pain relief. Long‐term follow‐up was available for 8 horses; none had any long‐term complications.Clinical Relevance— Partial amputation of the penis with pexy to the ventral abdomen and revision of the peripreputial skin can be used as an alternative to en bloc resection and penile retroversion for lesions involving the free part of the penis and the prepuce. It requires smaller incisions and results in less alteration to the normal appearance of the external genitalia than retroversion techniques, while still allowing the surgeon to remove extensive portions of the penis and extirpate the regional lymph nodes.
Generalized forgetting functions for on‐line least‐squares identification of time‐varying systems
Authors: Mahony R. E. , Lozano R. 
Published: August 2002

AbstractThe problem of on‐line identification of a parametric model for continuous‐time, time‐varying systems is considered via the minimization of a least‐squares criterion with a forgetting function. The proposed forgetting function depends on two time‐varying parameters which play crucial roles in the stability analysis of the method. The analysis leads to the consideration of a Lyapunov function for the identification algorithm that incorporates both prediction error and parameter convergence measures. A theorem is proved showing finite time convergence of the Lyapunov function to a neighbourhood of zero, the size of which depends on the evolution of the time‐varying error terms in the parametric model representation. Copyright © 2001 John Wiley & Sons, Ltd.
Tin soaps in emulsion PVC heat stabilization
Authors: Arkiş Esen , Balköse Devri̇m 
Published: August 2002

AbstractIn this study, the effect of a liquid stabilizer based on organotins on PVC heat stability is investigated. Control and films with tin soap heat stabilizer Sn500K were prepared by solvent casting and they were heated at 160 and 180°C for different time periods. X‐ray fluorescence spectroscopy analysis showed that tin was present in Sn500K and it was lead‐free. DSC analysis showed that glass‐transition temperature of films with Sn500K increased from 67 to 75–85°C by heating for 15 min at 180°C. IR spectroscopy indicated that concentration of carboxylate groups of Sn500K decreased with heating. Films with Sn500K did not degrade for short heating periods; however, degradation occurred in long heating times. Low concentration of Sn500K was recommended, since at high levels incompatibility with PVC and acceleration of degradation was observed. In the high temperature range, control and stabilized samples degraded in the same manner in two steps. © 2002 John Wiley & Sons, Inc. Adv Polym Techn 21: 65–73, 2002; DOI 10.1002/adv.10008
Preparation and characterization of SiO2‐functionalized phenolic resin hybrid materials
Authors: Hernández‐Padrón G. , Lima R. M. , Nava R. , García‐Garduño M. V. , Castaño V. M. 
Published: August 2002

AbstractThe preparation and characterization of a hybrid material produced by the combination of a modified aldehydic–phenolic resin (MPR) of the Novolac‐type with an inorganic oxide is described. Silica sols were embedded within a phenolic resin matrix of a modified Novolac‐type. Functionalization of the resin with the introduction of carboxylic groups in the course of the reaction is key to rendering a strong chemical union between the silanol groups of the SiO2 substrate and the COOH groups attached to the MPR resin, producing a core (SiO2)‐shell (MPR) structure. The hybrid samples were characterized by spectroscopic techniques (FT‐IR and FT‐Raman), XRD, TEM, and SEM. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 116–124, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10015
Estimation of elongational viscosity of polymers from entrance loss data using individual parameter optimization
Authors: Gupta Mahesh 
Published: August 2002

AbstractThe elongational viscosity model proposed by Sarkar and Gupta (Journal of Reinforced Plastics and Composites 2001, 20, 1473), along with the Carreau model for shear viscosity is used for a finite element simulation of the flow in a capillary rheometer. The entrance pressure loss predicted by the finite element flow simulation is matched with the corresponding experimental data to predict the parameters in the elongational viscosity model. To improve the computational efficiency, various elongational viscosity parameters are optimized individually. Estimated elongational viscosity for a Low Density Polyethylene (Dow 132i) is reported for two different temperatures. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 98–107, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10017
Temporal sequence of splenic dysfunction in sickle cell disease
Authors: Adekile A.D. , Owunwanne A. , Al‐Za'abi K. , Haider M.Z. , Tuli M. , Al‐Mohannadi S. 
Published: August 2002

AbstractSickle cell patients develop splenic dysfunction early in the course of their disease as shown by failure to visualize the organ on technetium‐99m colloid scintigraphy. However, preliminary studies from our center have shown that, when the spleen is not demonstrable on colloid uptake, it may be visualized on technetium‐99m heat‐denatured RBC scintigraphy. With time, however, the spleen can no longer be visualized with both tests in many patients. We have studied 46 patients aged 2 to 16 years, which included 36 SS, 7 Sβ0 thal, and 3 SD. Eighteen (39.1%) had normal splenic colloid uptake (Group 1), 15 (32.6%) had partial uptake (Group 2), and 13 (28.3%) had absent uptake (Group 3). When the patients in Group 1 were compared to those in the two other groups, there was no significant difference in the mean age and Hb F values. However, the mean Hb of 10.2 g/dl in Group 1 was significantly higher than the value of 9.0 g/dl in the other two groups. In addition, 60% of the SS patients with normal uptake and 40% of those with partial or absent uptake had co‐existing α‐thal trait; the difference in this proportion is significant (χ2 = 85, P < 0.0001). Heat‐denatured RBC scintigraphy was carried out on five patients in Group 2, and the spleen was visible in all, while of 12 children in Group 3, the spleen was visible only in 4 patients. This study demonstrates that the phagocytic function of the spleen, which is tested by colloid uptake, is the first to be lost while the filtration function, tested by denatured RBC uptake, persists for much longer. This finding may have significant implications for the clinical symptomatology and therapeutic strategies of sickle cell disease. Am. J. Hematol. 69:23‐27, 2002. © 2002 Wiley‐Liss, Inc.
Castleman's disease and lymphoma: Report of eight cases in HIV‐negative patients and literature review
Authors: Larroche Claire , Cacoub Patrice , Soulier Jean , Oksenhendler Eric , Clauvel Jean‐Pierre , Piette Jean‐Charles , Raphael Martine 
Published: August 2002

AbstractCastleman's disease (CD) is a rare atypical lymphoproliferative disorder associated with a risk of developing malignant lymphoma. We have recorded 8 HIV‐negative patients presenting this association, 6 with non‐Hodgkin's lymphoma (NHL) and 2 with Hodgkin's disease (HD). After literature review, we analyzed all reported cases of association CD–NHL (n = 23) and CD–HD (n = 27). NHL is more often associated with multicentric CD, its diagnosis being concurrent with CD diagnosis or occurring within 2 years. B‐NHL is predominant (71%), and mantle cell lymphoma represents 40% of these B‐NHL cases. NHL displays an aggressive course and is liable for death, especially in multicentric CD. HD occurs in localized CD of plasma cell type, usually in the same areas, is more often of interfollicular subtype, and its clinical course seems better than NHL. The association of CD and lymphoma seems to be more than coincidental, and its pathogenesis is discussed. Am. J. Hematol. 69:119–126, 2002. © 2002 Wiley‐Liss, Inc.
Acute lymphoblastic leukemia in the elderly: The Edouard Herriot hospital experience
Authors: Thomas Xavier , Olteanu Nicoleta , Charrin Christiane , Lhéritier Véronique , Magaud Jean‐Pierre , Fiere Denis 
Published: August 2002

AbstractData on all patients with acute lymphoblastic leukemia (ALL) aged 60 or older, referred to our institution over a 18‐year period, were studied to determine the incidence and range of clinical and biological subtypes, and the outcome of different therapeutic approaches. Sixty‐nine ALL cases (median age: 68 years) were diagnosed between 1980 and 1998 (18% of all adult ALL seen during this period). Ten of them (14%) had a past history of previous malignancy. Karyotypic analysis was performed successfully in 42 cases. Ten patients were diagnosed as Philadelphia chromosome positive (Ph+) ALL. Immunophenotyping was performed in 63 cases. Fifty‐six patients had B‐cell lineage ALL. T lymphoid markers were observed only in 5 cases. Co‐expression of myeloid markers was observed in 19% of tested cases. Five patients died before any chemotherapy could be given. All other patients received “curative” treatment according to different protocols used during the period of study. Overall complete remission (CR) rate of these patients was 62% (95% confidence interval (CI): 50–74%). Thirty‐nine patients achieved CR after one course of chemotherapy and 4 patients after salvage therapy. Median disease‐free survival (DFS) of the entire cohort was 8.3 months (95% CI: 5–12.8 months) and median overall sur‐ vival was 7 months (95% CI: 6–10 months). In multivariate analysis, the presence of hemorrhage (P = 0.02) was a poor prognostic for CR achievement. Higher WHO performance status (P = 0.003) and the presence of hemorrhage (P = 0.01) at diagnosis were poor prognostics for overall survival. When patients were stratified into three groups according to the time of admission, survival appeared significantly longer for patients admitted between July 1992 and December 1998 (median overall survival at 10 months) than for patients admitted before July 1992 (P = 0.04). “Age‐adapted” therapy appeared superior to “young adult‐like” therapy in terms of CR rate (96% versus 60%; P = 0.007). However, “age‐adapted” therapy did not show any advantage in terms of DFS or overall survival, making the difference in CR rates questionable. We conclude that the pejorative overall outcome in elderly ALL points to the need for new therapeutic trials taking into account the specific characteristics of ALL in this age group. Am. J. Hematol. 67:73–83, 2001. © 2001 Wiley‐Liss, Inc.
In vitro exposure to hydroxyurea reduces sickle red blood cell deformability
Authors: Huang Zhi , Louderback Joseph G. , King S. Bruce , Ballas Samir K. , Kim‐Shapiro Daniel B. 
Published: August 2002

AbstractHydroxyurea is a drug that is used to treat some patients with sickle cell disease. We have measured the deformability of sickle erythrocytes incubated in hydroxyurea in vitro and found that hydroxyurea acts to decrease the deformability of these cells. The deformability of normal erythrocytes was not significantly affected by hydroxyurea except at very high concentrations. Hydroxyurea also did not consistently reduce the deformability of sickle erythrocyte ghosts. We propose that the decreased deformability, observed in vitro, is due to the formation of methemoglobin and other oxidative processes resulting from the reaction of hydroxyurea and oxyhemoglobin. Although the reaction with normal hemoglobin is similar to that of sickle hemoglobin, the sickle erythrocytes are affected more. We propose that the sickle erythrocyte membrane is more susceptible to the reaction products of the reaction of hemoglobin and hydroxyurea. An earlier report has shown that hydroxyurea increases the deformability of erythrocytes in patients on hydroxyurea. Taken together, these data suggest that the improved rheological properties of sickle erythrocytes in vivo are due to the elevated numbers of F cells [cells with fetal hemoglobin]. The presence of the nitrosyl hemoglobin or methemoglobin from the reaction with hydroxyurea may also benefit patients in vivo by reducing sickling. Am. J. Hematol. 67:151–156, 2001. © 2001 Wiley‐Liss, Inc.
Hemoglobin H (Hb H) disease in Canada: Molecular diagnosis and review of 116 cases
Authors: Waye John S. , Eng Barry , Patterson Margaret , Walker Lynda , Carcao Manuel D. , Olivieri Nancy F. , Chui David H.K. 
Published: August 2002

AbstractOver the past decade, we have characterized at the DNA level a total of 116 hemoglobin H (Hb H) disease patients living in Canada. The majority of patients were of southeast Asian descent (Chinese, Filipino, Laotian, Vietnamese), with a small number being of Mediterranean, Middle Eastern or East Indian background. A total of 15 distinct genotypes were detected, all but one being compound heterozygotes for a two‐gene cis deletion and a single‐gene deletion (‐α/−) or a non‐deletion mutation of the α2‐globin gene (αT α/−). Seven different two‐gene cis deletions were encountered, along with nine single‐gene deletions and point mutations. The wide range of mutations associated with Hb H disease in Canada is a reflection of the population heterogeneity. The diagnosis of Hb H disease at the molecular level is important with respect to genetic counseling and the identification of families at risk for having pregnancies affected with Hb Bart's hydrops fetalis syndrome and/or Hb H disease. Six of the Hb H disease patients in our cohort had spouses who carried single‐gene deletions, making these couples at risk for having children with Hb H disease. More important, seven patients had partners who carried two‐gene cis deletions. These couples are at reproductive risk for both Hb Bart's hydrops fetalis syndrome and Hb H disease. Am. J. Hematol. 68:11–15, 2001. © 2001 Wiley‐Liss, Inc.
Stature and stature distribution in Portuguese male adults 1904–1998: The role of environmental factors
Authors: Padez Cristina 
Published: August 2002

AbstractThe records of height of 841,457 18‐year‐old Portuguese males were analyzed by area of residence (districts). The sample included all Portuguese 18‐year‐old males born between 1966 and 1979 and examined between 1985 and 1998, in the north, center, and south of Portugal. They represent all social strata. There were statistically significant differences (P ≤ 0.001) among districts: males from Lisbon (172.8 cm) and Setúbal (172.7 cm), the most developed districts, were tallest, and those from Madeira (169.7 cm) and Coimbra (171.6 cm) were shortest. Compared with published data for 1904, there was a positive secular trend in height. The average increase was 8.93 cm and the estimated rate was 0.99 cm per decade. The changes that occurred were mainly the result of the reduction of the shortest classes of stature, those <150 cm to 170 cm, and an increase in the frequency of the highest classes, ≥170 cm. This positive trend and the changes in stature distribution must be related to the general improvement in standard living conditions that occurred in Portugal primarily after the 1960s and 1970s, especially in terms of nutrition and the health system. Taking into account the socioeconomic differences that still exist between districts, the results suggest that the secular trend in height should continue for the Portuguese population in future decades. Am. J. Hum. Biol. 14:39–49, 2002. © 2002 Wiley‐Liss, Inc.
Risk factors for back pain among male farmers: Analysis of Iowa Farm Family Health and Hazard Surveillance Study
Authors: Park Hyesook , Sprince Nancy L. , Whitten Paul S. , Burmeister Leon F. , Zwerling Craig 
Published: August 2002

AbstractBackgroundBack pain causes considerable morbidity, disability, and economic loss among workers. Farmers handle heavy objects, often in awkward postures. However, the prevalence of back pain among farmers and the risk factors associated with back pain are not well known.MethodsIn this study, we assess the frequency of risk factors for back pain among 287 Iowa male farmers. From 1992 to 1994, using a mail questionnaire, we collected data on potential risk factors for back pain. Eighteen months later, we surveyed occurrence of back pain as the outcome measure.ResultsThirty‐one percent of farmers reported having daily back pain for a week or more during the past 12 months compared to 18.5% in the general working population. Using a multiple logistic regression model, we found two factors associated with back pain: 45–59 years of age (OR = 2.13, 95% CI 1.02–4.43) and having a non‐agricultural job as the major occupation (OR = 2.02, 95% CI 0.98–4.17, P = 0.055).ConclusionsFarmers had a significantly higher prevalence of back pain than the general working population. Middle‐aged farmers and those with additional non‐agricultural jobs had the highest risk for back pain. Am. J. Ind. Med. 40:646–654, 2001. © 2001 Wiley‐Liss, Inc