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IntroductionThere is controversy regarding the ideal pancreaticojejunostomy technique after pancreaticoduodenectomy. Many authors consider the external Wirsung stenting technique to be associated with a low incidence of fistula, morbidity and mortality. We analyse our experience with this technique.Patients and methodsA retrospective analysis of the morbidity and mortality of a series of 80 consecutive patients who had been treated surgically over a 6.5-year period for pancreatic head or periampullary tumors, performing pancreaticoduodenectomy and pancreaticojejunostomy with external Wirsung duct stenting.ResultsMean patient age was 68.3 ± 9 years, and the resectability rate was 78%. The texture of the pancreas was soft in 51.2% of patients and hard in 48.8%. Pylorus-preserving resection was performed in 43.8%. Adenocarcinoma was the most frequent tumor (68.8%), and R0 was confirmed in 70% of patients. Biochemical fistula was observed in 11.2%, pancreatic fistula grade B in 12.5% and C in 2.5%, whereas the abdominal reoperation rate was 10%. Median postoperative hospital stay was 16 days, and postoperative and 90-day mortality was 2.5%. Delayed gastric emptying was observed in 36.3% of patients, de novo diabetes in 12.5%, and exocrine insufficiency in 3. Patient survival rates after 1, 3 and 5 years were 80.2, 53.6 and 19.2%, respectively.ConclusionsAlthough our low rates of postoperative complications and mortality using external Wirsung duct stenting coincides with other more numerous recent series, it is necessary to perform a comparative analysis with other techniques, including more cases, to choose the best reconstruction technique after pancreaticoduodenectomy.  相似文献   
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Slices (n = 45) from the somatosensory cortex of mouse (P8-13) generated spontaneous bursts of activity (0.10 +/- 0.05 Hz) that were recorded extracellularly. Multiunit action potential (AP) activity was integrated and used as an index of population activity. In this experimental model, seizure-like activity (SLA) was evoked with bicuculline (5-10 microM) or N-methyl-d-aspartate (NMDA, 5 microM). SLA was an episode with repetitive bursting at a frequency of 0.50 +/- 0.06 Hz. To evaluate whether SLA was associated with a change in synchrony, we obtained simultaneous intracellular and extracellular recordings (n = 40) and quantified the relationship between individual cells and the surrounding population of neurons. During the SLA there was an increase in population activity and bursting activity was observed in neurons and areas that were previously silent. We defined synchrony as cellular activity that is consistently locked with the population bursts. Signal-averaging techniques were used to determine this component. To quantitatively assess change in synchronous activity at SLA onset, we estimated the entropy of the single cell's spike trains and subdivided this measure into network burst-related information and noise-related entropy. The burst-related information was not significantly altered at the onset of NMDA-evoked SLA and slightly increased when evoked with bicuculline. The signal-to-noise ratio determined from the entropy estimates showed a significant decrease (instead of an expected increase) during SLA. We conclude that the increased population activity during the SLA is attributed to recruitment of neurons rather than to increased synchrony of each of the individual elements.  相似文献   
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Congenital deafness is a relatively frequent disorder that shows a heterogeneous aetiology. Knowledge and the control of some risk factors have decreased the incidence of acquired deafness and increased the relative importance of genetic cause. In an attempt to investigate the clinical relevance of congenital deafness and the mechanisms of prevention in our population, a clinical and genetic study of cases with neurosensorial deafness born in Navarra between 1975 and 1990 was carried out. A total of eighty-one cases were identified, giving an incidence of 0.8 per thousand. Thirty per cent of the cases showed deafness associated with defects. Cause of deafness was identified in seventy per cent of the cases with whom a detailed clinical and genetic study could be performed (n=50). Genetic factors were responsible for the disorder in more than half of these cases. The most frequent hereditary factor was of the autosomic recessive type. This was associated with a more severe form of hearing loss.  相似文献   
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The association of certain human papillomavirus (HPV) types with malignancies of the anogenital tract is well established. The virus type most frequently associated with cellular transformation is HPV 16, as has been shown in epidemiological studies. Its transforming capacity has also been demonstrated in many in vitro cell transformation experiments. The most potent oncogenes of HPV 16 are the E6 and E7 proteins, but the E5 protein, whose homologue is the main oncogene of bovine papillomavirus, has recently been identified as an oncogene also for HPV. On the basis of epidemiological and clinical data from tumor material as well as from in vitro data it has been suggested, that the HPV 16 E5 protein would have a function at the early stages of cervical carcinogenesis. The E5 protein enhances growth factor-mediated signal transduction to the nucleus and consequently augments cellular proliferation. Expression of the E5 protein enables the infected cell to escape growth control provided by surrounding cells by inhibiting gap junctional intercellular communication in epithelial cells. This viral oncogene seems to interfere with the control mechanisms of cellular growth and proliferation and thus facilitate the function of the E6 and E7 proteins and further steps towards epithelial cell transformation.  相似文献   
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The tetrameric STRs, HUMTH01, HUMVWA31A and HUMFES/FPS, were studied in a population from the Basque Country (northern Spain) for their frequency distribution and applicability to identity and paternity testing. All systems conformed to Hardy-Weinberg equilibrium; pairwise comparisons demonstrated the allelic independence between loci, and furthermore, all systems seemed to be in agreement with expectations from the Stepwise Mutation Model (SMM) of the mutation-drift theory, which indicates the homogeneity of the population and suggests a replication slippage mechanism as a possible model for generating alleles. A comparison with other population groups appeared to indicate that frequencies are well conserved in Caucasians, but differ from other racial groups. The calculated parameters a priori probability of exclusion (PEX) and index of discrimination (ID), show the informativeness of these loci for the determination of identity and relatedness of individuals.  相似文献   
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In addition to the known compounds (+/-)-threo-guaiacylglycerol and the phenethyl alcohols, 3-methoxy-4-dihydroxyphenethyl alcohol and 3,4-dimethoxyphenethyl alcohol, a new irregular phenylpropanoid 2-(3-methoxy-4-hydroxyphenyl)-1,3-propanediol was isolated from the ethanolic extract of the leaves of Apollonias barbujana (Lauraceae). Their structures were elucidated on the basis of spectroscopic methods and chemical transformations.  相似文献   
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