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The development of both adenocarcinoma of the jejunum and in situ squamous carcinoma of the oesophagus in an adult coeliac patient is described. Good evidence that adenocarcinoma of jejunum occurs more frequently in patients with coeliac disease has recently become available though this association has been suggested for some time. While oesophageal carcinoma has long been associated with coeliac disease, in situ carcinoma of oesophagus has not been previously described in these circumstances. We feel that the risk of this complication, as calculated from published series, warrants a screening programme for oesophageal malignancy in adult coeliacs.  相似文献   
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Social stress in guinea pigs   总被引:1,自引:0,他引:1  
Confrontation studies between eight pairs of two 7-8 months old male guinea pigs, each raised with one female from their 30th day of age, were conducted in an enclosure of 2 m2 in the presence of an unfamiliar female. The opponents were chronically kept together for up to 8 days. When they were not separated after 52 hr, one or (in 1 case) both males fell into a comatose state and died 5-8 days after the onset of the confrontation. Four hr after the onset of the confrontations both opponents showed significantly increased plasma glucocorticoid (CS) titers. At this time as well as 24 hr earlier, prospective winners (PW) and prospective losers (PL) did not yet differ in any physiological parameter measured. Forty-eight hr later, PW were characterized by a low body weight loss, low CS, high testosterone (T) and elevated plasma-catecholamine (CA) values. In contrast, PL showed a high body weight loss, very high CS titers, low T-titers and more elevated CA values than PW. Despite these highly significant differences in physiological parameters, PL and PW did not yet differ in the frequency of any agonistic behavioral element recorded. Seventy-two hr after the onset of the chronic cohabitation, losers began to behave more and more passive, they ceased feeding and drinking and were less and less involved in social interactions. The physiological differences between winners and losers intensified.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Predictive value of normal sperm morphology: a structured literature review   总被引:12,自引:0,他引:12  
The aim of the study was to conduct a structured review of theliterature published on the use of normal sperm morphology,as an indicator of male fertility potential in the in-vitrofertilization (IVF) situation, and to establish the universalpredictive value of this semen parameter. Published literaturein which normal sperm morphology was used to predict fertilizationand pregnancy, during the period 1978-1996, was reviewed. Atotal of 216 articles were identified by the sourcing methodology,but only 49 provided data that could be tabulated and analysed.Of these, only 18 provided sufficient data for statistical analysis.Fifteen studies used the strict criteria to evaluate sperm morphology,two used World Health Organization (WHO) guidelines and oneused both the strict criteria and the WHO guidelines. All thestudies (n=10) using the 5 and 14% normal sperm morphology thresholds(strict criteria) produced positive predictive values for IVFsuccess. In the prediction of pregnancy, 82% (9/11) and 75%(6/8) of the studies produced positive predictive values whenusing the 5% and 14% thresholds respectively. Aggregating thedata produced around the 5% normal sperm morphology threshold(strict criteria), the overall fertilization rates were 59.3%(1979/3337; per oocyte) for the 4% group and 77.6% (10345/13327;per oocyte) for the >4% group, and the overall pregnancyrates were 15.2% (60/395; per cycle) and 26.0% (355/1368; percycle) respectively. The no-transfer rates across the 5% thresholdwere 24.0% (86/359; per cycle) in the 4% group compared to 7.4%(80/1088; per cycle) in the >4% group. The inclusion of anaccurately evaluated normal sperm morphology count as an integralpart of the standard semen analysis makes this analysis stillthe most cost-effective means of evaluating the male factor.  相似文献   
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Unlike dialysis, which functions as a bridge to renal transplantation, or a ventricular assist device, which serves as a bridge to cardiac transplantation, no suitable bridge to lung transplantation exists. Our goal is to design and build an ambulatory artificial lung that can be perfused entirely by the right ventricle and completely support the metabolic O2 and CO2 requirements of an adult. Such a device could realize a substantial clinical impact as a bridge to lung transplantation, as a support device immediately post-lung transplant, and as a rescue and/or supplement to mechanical ventilation during the treatment of severe respiratory failure. Research on the artificial lung has focused on the design, mode of attachment to the pulmonary circulation, and intracorporeal versus paracorporeal placement of the device.  相似文献   
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