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31.
J. N. Laverri re J. L. Richard A. Morin N. Buisson A. Tixier-Vidal W. B. Huttner D. Gourdji 《Molecular and cellular endocrinology》1991,80(1-3):41-51
Secretogranin I (SgI; chromogranin B) belongs to a class of acidic tyrosine-sulfated secretory proteins believed to play a role in the secretory process of endocrine cells. Our aim here was to compare the levels of SgI mRNA to that of prolactin (PRL) and growth hormone (GH), using rat pituitary cell lines. As far as the constitutive expression is concerned, we found a positive correlation between SgI mRNA and PRL mRNA levels. However, the neuropeptide TRH (50 nM) inhibited the accumulation of SgI mRNA in GH3B6 cells whereas, as expected, it induced a rapid and sustained increase in PRL mRNA accumulation. By contrast, 17β-estradiol (1 nM) stimulated the accumulation of both SgI and PRL mRNAs, with the same EC50 (18–59 pM). Reciprocally, treatment with dexamethasone (100 nM) reduced the level of SgI and PRL mRNAs to 23% and 29% of control, respectively, but led to a 2.1-fold increase in the GH mRNA level. Altogether, the present work shows that SgI gene expression is subject to multiple hormonal regulations and occasionally parallels the regulation of the PRL gene but never that of the GH gene, under the conditions tested. 相似文献
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Gabriela A Ghitulescu Nancy Morin Prasad Jetty Paul Belliveau 《Canadian journal of surgery》2003,46(2):92-98
INTRODUCTION: The use of the biofragmentable anastomotic ring (BAR) has been reported in the literature with good results. Our purpose in this review was to document the clinical outcomes after gastrointestinal anastomoses performed with use of the BAR. METHODS: Data were gathered systematically through chart review with the help of data collection forms from 159 patients who underwent 173 intestinal anastomoses performed with use of the BAR between 1992 and 1999. Of the 165 patients who had anastomoses (6 had 2 anastomoses constructed on separate occasions and were considered separately), 23 (13.9%) had surgery with anastomosis under emergency conditions, and 44 (26.7%) were steroid-dependent patients. The indications for surgery were malignant disease in 63 (38.2%) patients, inflammatory bowel disease in 54 (32.7%) patients, diverticular disease in 13 (7.9%) patients and other conditions in 35 (21.2%) patients. RESULTS: A clinical anastomotic leak developed in the first 2 weeks after surgery in 7 (4.2%) patients, 6 of whom required reoperation. All recovered well, withno deaths related to use of the BAR. Early small-bowel obstruction developed in 13 patients (7.9%), none of whom required reoperation. The average postoperative length of hospital stay was 9.0 days, the average time to pass the first flatus was 3.2 days, and the average time to begin oral fluid intake was 3.3 days. The rate of leakage at the anastomosis in our series was comparable to that found in randomized trials with the BAR (2.0%-4.4%) and as reported with hand-sewn and stapled anastomoses (1.9%-8.2%). CONCLUSIONS: Our data indicate that use of the BAR is safe and effective in both elective and emergent surgery. The rate of leakage is comparable to that reported in the literature when a BAR is used. 相似文献
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Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
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We examined capacity related properties of "Glyco-Gel" (Pierce), a boronate agarose gel for separating and measuring glycated proteins by affinity chromatography. Our data indicate linear capacity to as much as 20 mg as applied hemoglobin or almost 10 mg as bound hemoglobin and 26 mg as applied serum proteins or a minimum of 2.5 mg as bound serum protein for each mL of gel. The capacity and affinity of the support for glycated proteins becomes optimum only after four regeneration cycles. The support matrix appears to have a small concentration of nonspecific binding sites equivalent to 0.09 to 0.18 mg as serum protein for each mL of gel. These sites do not bind hemoglobin. They lead to an overestimation of glycated protein that can cause large errors when the proportion of glycated protein is determined with small column loads. If near capacity loads are applied, the samples must be dialyzed or diluted to avoid decreased analytical recovery resulting from competitive and eluting properties of endogenous sugars. 相似文献
38.
S. Urien D. Morin A. Renouard I. Rocher J.-P. Tillement 《European journal of clinical pharmacology》1988,34(4):381-385
Summary The serum concentrations of 1-acid glycoprotein (AAG), albumin (HSA) and non-esterified fatty acids, and the serum binding of tertatolol were measured in four groups of individuals: healthy control subjects (n=24), and patients with inflammation (n=28), and hepatic (n=20) and renal (n=27) insufficiency.Serum binding of tertatolol was increased in patients with inflammation (94.6%), decreased in patients with hepatic insufficiency (88.8%) and it was unchanged in patients with renal insufficiency (92.8%) as compared to controls (92.7%).Multivariate analysis indicated that the changes were mainly related to concomitant changes in AAG concentration, which could account for 57% of intersubject variability in the bound/free ratio, and to a lesser extent in HSA, which accounted for only 4% of the variability in the binding.The data show that the free fraction of the basic drug tertatolol in serum is affected by pathological conditions that cause changes in AAG concentration. 相似文献
39.
Application of reflectance spectroscopy to the estimation of uric acid, urea and glucose: an evaluation of the Ames Seralyzer
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An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres. 相似文献
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