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51.
GQ Phan CJ Yeo JL Cameron MM Maher RH Hruban R Udelsman 《Canadian Metallurgical Quarterly》1997,122(6):989-96; discussion, 996-7
BACKGROUND: Most resectable pancreatic or peripancreatic neuroendocrine tumors are treated by enucleation or distal pancreatectomy. A minority of tumors may require pancreaticoduodenectomy for complete tumor excision because of their large size, location, or lymph node involvement. METHODS: This study reviews the management of 50 patients treated by pancreaticoduodenectomy for periampullary neuroendocrine tumors between 1962 and 1996 at a single institution. RESULTS: There were 30 men and 20 women with a mean age of 52 +/- 2 years. Functional tumors were resected in 17 patients: insulinoma, seven tumors; gastrinoma, eight tumors; vipoma, one tumor; and glucagonoma, one tumor. Tumors were classified as malignant in 29 patients and benign in 21. The median intraoperative blood loss was 800 ml, and the median number of units of blood transfused was zero. The postoperative length of stay was 20 +/- 2 days. Postoperative morbidity included 11 patients (24%) with a pancreatic fistula and four patients (8%) with a biliary fistula. There was one in-hospital death (2%), in 1967. The actuarial survival rates at 2, 5, and 7 years are 81%, 73%, and 65%, respectively. Patients with benign tumors had a significantly improved 5-year survival rate (94%) compared with those with malignant tumors (61%; p = 0.03). CONCLUSIONS: Selected patients with periampullary neuroendocrine tumors can be managed successfully by pancreaticoduodenectomy, with low mortality and acceptable morbidity rates. 相似文献
52.
RH Rau YL Chan HI Chuang CR Cheng KL Wong KH Wu TT Wei 《Canadian Metallurgical Quarterly》1997,35(2):113-118
While current psychiatric taxonomies recognise a classification of amphetamine dependence, derived from the notion of an alcohol dependence syndrome, little research has validated that such a condition exists for this drug. Current amphetamine users (N = 331), were interviewed using the World Health Organization operationalisation of DSM-III-R substance dependence criteria, and a measure of the psychological components of dependence. Structural analyses indicated that a unidimensional dependence syndrome as assessed by DSM-III-R and DSM-IV criteria exists for amphetamine, and that physiological, psychological and behavioural indicators were all important in accounting for the variance in responses. It was demonstrated that the concept of a dependence syndrome is applicable to amphetamine, and that the inclusion of the amphetamine dependence syndrome in DSM-III-R and DSM-IV is valid. 相似文献
53.
Three experiments were conducted to test fertility when sperm numbers per insemination ranged from 10 x 10(6) to 40 x 10(6) total sperm. All semen was from Holstein bulls that were on a regular schedule of semen collection. The semen was extended with heated homogenized whole milk, cooled, glycerolated, and frozen according to standard procedures. Semen was distributed to a large group of inseminators to minimize differential field effects on treatment. All experiments were a randomized block design, including a split plot in Experiment 2. In Experiment 1, data for 31,399 first inseminations distributed among treatments of 20 x 10(6), 25 x 10(6), 30 x 10(6), and 40 x 10(6) total sperm resulted in 69.8, 70.0, 70.1, and 70.1% nonreturns at 59 d, respectively. In Experiment 2, data for 18,197 first inseminations divided over treatments of 12 x 10(6), 16 x 10(6), and 20 x 10(6) total sperm resulted in 70.2, 72.4, and 70.8% nonreturns at 59 d, respectively. In Experiment 3, 38,890 first inseminations distributed over treatments of 10 x 10(6), 13 x 10(6), 16 x 10(6), and 20 x 10(6) total sperm resulted in 70.5, 72.2, 73.1, and 71.5% nonreturns at 59 d, respectively. Bull nonreturns ranged from 64 to 76% in the three trials. These results indicate that, under good conditions, total sperm numbers per straw can be reduced to 10 x 10(6) total sperm with a reduction of nonreturn rates at 59 d, for most bulls, of about 1 percentage unit from the maximum when professional inseminators are use. 相似文献
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55.
Swaminathan Sivasubramanian Guillaume Pierre Maarten van Steen Gustavo Alonso 《Internet Computing, IEEE》2007,11(1):60-66
Developers often use replication and caching mechanisms to enhance Web application performance. The authors present a qualitative and quantitative analysis of state-of-the art replication and caching techniques used to host Web applications. Their analysis shows that selecting the best mechanism depends heavily on data workload and requires a careful review of the application's characteristics. They also propose a technique for Web practitioners to compare different mechanisms' performance on their own 相似文献
56.
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58.
H Reznik-Wolf TA Treves M Davidson J Aharon-Peretz PH St George Hyslop J Chapman AD Korczyn B Goldman E Friedman 《Canadian Metallurgical Quarterly》1996,98(6):700-702
Germline mutations in the presenilin 1 (PS1) gene apparently account for the majority of early-onset, familial Alzheimer's disease (AD). Using a mutation-screening strategy (denaturing gradient gel electrophoresis; DGGE), we analyzed a large family with early onset AD and seizures. The patients in this family showed a novel missense mutation in exon 5 of the PS1 gene (A to T change in codon 120, altering glutamine to aspartic acid). This novel mutation is located within the second hydrophilic domain of the molecule, a region not particularly involved in previously described germline mutations, and is of unknown biological significance. These results also demonstrate that DGGE can be used effectively to screen for mutations within this gene. 相似文献
59.
60.
Résumé Cet article présente un modèle permettant de calculer le fluage de poutres fléchies de différentes sections soumises à des
environnements variables en ce qui concerne l'humidité relative. Ce modèle est utilisé ici pour interpréter de nouveaux essais
à long terme sur des poutres en bois massif et lamellé-collé qui ont été chargées pendant plus de 800 jours en conditions
extérieures sous abri à Paris
Summary Long term bending experiments on full size timber and glulam beams have been carried out under external and sheltered climatic conditions in Paris, and more than two years of test results on the creep behaviour of 75 beams are available. A model for predicting the long term mechanical behaviour of timber under variable humidity and load conditions, previously developed by the author, is described. The model is based on transient moisture transfer analysis linked with deformation analysis using a step-by-step computation scheme, and has been compared previously with experiments carried out under laboratory conditions of controlled variable climates by the author as well as with test results obtained from several other institutions. In general, the model has agreed satisfactorily with the experimental results. In the present paper the model is compared with experiments on full size beams carried out under the changeable conditions of a natural climate. The results show that, for low stress levels and corresponding loads, the model provides a reasonable prediction of the end creep levels after two years of loading.相似文献