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81.
BACKGROUND/AIMS: The outcome of endoscopic biliary stent insertion for postoperative bile duct stenosis was retrospectively evaluated. METHODOLOGY: Fifty-seven patients with biliary stenosis from laparoscopic cholecystectomy were included from February 1992 to January 2000. One to three stents were inserted for an average of 12.4 months, with stent exchange every 3 months to avoid cholangitis caused by clogging. RESULTS: Successful stent insertion was achieved in 43/57 (75.4%) patients. Stent insertion failed in 10 patients with complete and in 4 patients with incomplete biliary obstruction. Early complications occurred in 4 patients. Late complications occurred in 5/43 patients. Five patients experienced recurrence of stenosis. CONCLUSIONS: Endoscopic treatment should be the initial management of choice for postoperative bile duct stenosis.  相似文献   
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Ovarian steroids modulate the action of calcitonin in women   总被引:1,自引:0,他引:1  
Slow i.v. infusion of salmon calcitonin into normal women led to a transient increase in plasma concentrations of cyclic AMP and to a decrease in plasma calcium, which was maintained for at least 2 h. These responses were significantly reduced in the same patients after hysterectomy and ovariectomy. In contrast, maintenance of the ovaries at the time of surgery, or substitutive hormonal therapy, seemed to restore the sensitivity to exogenous calcitonin, suggesting a permissive role of ovarian steroids in the effect of calcitonin. The most likely explanation for this phenomenon is that these hormones influence either the number of calcitonin receptors or the coupling of the receptors to the functional unit of bone adenylate cyclase.  相似文献   
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Tumor necrosis factor alpha (TNFα) in intestinal mucosa plays a key role in the inflammation characterizing Crohn’s disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFα and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFα and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFα and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFα in CD. In conclusion, TNFα and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFα.  相似文献   
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International Journal of Legal Medicine - The motor vehicle crash (MVC) constitutes an important challenge for forensic pathology in order to identify the manner and cause of death. Our study...  相似文献   
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BackgroundNeurosteroids affect the balance between neuroexcitation and neuroinhibition but have been little studied in migraine. We compared the serum levels of pregnenolone sulfate, pregnanolone and estradiol in women with menstrually-related migraine and controls and analysed if a correlation existed between the levels of the three hormones and history of migraine and age.MethodsThirty women (mean age ± SD: 33.5 ± 7.1) with menstrually-related migraine (MM group) and 30 aged- matched controls (mean age ± SD: 30.9 ± 7.9) participated in the exploratory study. Pregnenolone sulfate and pregnanolone serum levels were analysed by liquid chromatography-tandem mass spectrometry, while estradiol levels by enzyme-linked immunosorbent assay.ResultsSerum levels of pregnenolone sulfate and pregnanolone were significantly lower in the MM group than in controls (pregnenolone sulfate: P = 0.0328; pregnanolone: P = 0.0271, Student’s t-test), while estradiol levels were similar. In MM group, pregnenolone sulfate serum levels were negatively correlated with history of migraine (R2 = 0.1369; P = 0.0482) and age (R2 = 0.2826, P = 0.0025) while pregnenolone sulfate levels were not age-related in the control group (R2 = 0.04436, P = 0.4337, linear regression analysis).ConclusionLow levels of both pregnanolone, a positive allosteric modulator of the GABAA receptor, and pregnenolone sulfate, a positive allosteric modulator of the NMDA receptor, involved in memory and learning, could contribute either to headache pain or the cognitive dysfunctions reported in migraine patients. Overall, our results agree with the hypothesis that migraine is a disorder associated with a loss of neurohormonal integrity, thus supporting the therapeutic potential of restoring low neurosteroid levels in migraine treatment.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-021-01231-9.  相似文献   
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Ecotoxicology - Nanomaterials have revolutionized many scientific fields and are widely applied to address environmental problems and to develop novel health care strategies. However, their...  相似文献   
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