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F J Fenoy I Milicic M Mistry T E Mecca R J Roman 《The Journal of pharmacology and experimental therapeutics》1992,261(2):470-475
The present study evaluated the effects of a new benzothiazepine calcium channel antagonist, clentiazem, on arterial pressure and renal function in spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto (WKY) and Munich-Wistar rats (MWR). Administration of clentiazem in doses from 1 to 20 micrograms/kg/min produced dose-dependent increases in sodium and water excretion in MWR, reaching maximum values of 292 and 376% of control, respectively, at the 20-micrograms/kg/min dose. Clentiazem (10 micrograms/kg/min) lowered arterial pressure by 16% and doubled glomerular filtration rate (GFR) in MWR. The rise in GFR was associated with an increase in glomerular capillary pressure of 16 mm Hg, produced by a combination of preglomerular vasodilation and efferent arteriolar vasoconstriction. In SHR, administration of clentiazem (10 micrograms/kg/min) lowered arterial pressure by 30 mm Hg and increased urine flow and sodium excretion by 137 and 200%, respectively. In WKY rats, the same dose of clentiazem decreased arterial pressure by only 10 mm Hg, whereas urine flow and sodium excretion increased 62 and 38%, respectively. A high dose of clentiazem (1 mg/kg bolus plus 1 mg/kg/hr infusion i.v.) lowered arterial pressure by 63 mm Hg in SHR. Renal vascular resistance fell by 39% and there was a 5-fold increase in sodium excretion. In WKY rats, the same dose of clentiazem reduced arterial pressure by 20 mm Hg, but it had no significant effect on sodium excretion. These results indicate that clentiazem increases sodium excretion and GFR in normotensive rats in part by preferentially dilating the renal preglomerular vasculature. This compound is also an antihypertensive agent that lowers arterial pressure and promotes sodium excretion in SHR. 相似文献
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J. TE VELDE G. J. DEN OTTOLANDER P. J. SPAANDER C. VAN DEN BERG COCK A. HARTGRINK-GROENEVELD 《Histopathology》1978,2(1):31-46
One hundred and nineteen methacrylate-embedded trephine biopsy specimens from 80 patients with Hodgkin's disease are reviewed. Although marrow involvement was found in 4% of the untreated patients, the present study was mainly concerned with the marrow unaffected by specific infiltrates and in negative specimens. The non-involved bone marrow in Hodgkin's disease invariably showed alterations of three types; stromal damage, inflammatory infiltration, and disturbed haematopoiesis. Each of these features can be found in the absence of one or both of the others. In severe examples, all three of these components usually occur simultaneously, giving histological pictures that mimic Hodgkin-specific infiltrates, sometimes in association with clinical suggestions of bone marrow involvement or replacement. But trephine biopsies of sufficiently high histological quality offer alternative explanations for the pancytopenia, for instance intramedullary phagocytosis, reactive sclerosing inflammation resembling auto-immune disorders, or a disturbance of haematopoiesis itself. This disturbance could be due to a defect inherent in the haematopoiesis associated with Hodgkin's disease, possibly predisposing for leukaemia in longterm survivors who have received chemotherapy and/or irradiation. The disturbed erythropoiesis proved to be strongly correlated with the stage of the disease at the time of biopsy. This finding could contribute to staging procedures, when laparotomy is contraindicated. 相似文献
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MG Hayes M Urbanek M-F Hivert LL Armstrong J Morrison C Guo LP Lowe DA Scheftner A Pluzhnikov DM Levine CP McHugh CM Ackerman L Bouchard D Brisson BT Layden D Mirel KF Doheny MV Leya RN Lown-Hecht AR Dyer BE Metzger TE Reddy NJ Cox WL Lowe Jr. for the HAPO Study Cooperative Research Group. 《Diabetes》2013,62(10):3641
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Study ObjectiveThis study analyzed the relationship between household food security and variation in age at menarche, as well as the connections between food insecurity, nutritional status, and allostatic load, among girls aged 12-15 years from the 2009-2014 United States National Health and Nutrition Examination Survey (NHANES).MethodsData analysis included mean comparisons of age at menarche among household food security groups (high, marginal, low, and very low) as well as categorical variables known to associate with age at menarche (ethnicity, poverty status, body mass index [BMI], allostatic load, and milk consumption). χ2 Analyses were used to test the associations between household food security and additional categorical variables. Univariate and multivariate regression models were used to test the relationship between variation in age at menarche and household food security, ethnicity, BMI, and allostatic load categories while controlling for age.ResultsNon-Hispanic Black and Hispanic/Mexican American girls had earlier mean ages at menarche, higher mean BMIs, and disproportionately experienced household food insecurity when compared to non-Hispanic White-identifying girls. In the univariate analyses, marginal household food security, Hispanic/Mexican American and Black ethnicities, overweight and obese BMI categories, and marginal-high allostatic load were each associated with lower age at menarche compared to reference categories. These associations were maintained in the multivariate analysis, although only Hispanic/Mexican American ethnicity predicted earlier menarche when compared to that of non-Hispanic White girls.ConclusionsMarginal household food security, particularly for girls who identified as non-White, predicted earlier age at menarche independent of nutritional status and allostatic load. At the same time, having more energetic resources (ie, higher BMI) also significantly predicted earlier menarche. 相似文献
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Unusual artifact with mammography film 总被引:2,自引:0,他引:2