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41.
Hutchens Bridget Frese Holland Margaret L. Tanner Tanya Kennedy Holly Powell 《Maternal and child health journal》2021,25(4):613-625
Maternal and Child Health Journal - The purpose of this study was to examine if women’s perceptions of the quality of hospital care during childbirth moderate their risks for symptoms of... 相似文献
42.
Albright David L. McDaniel Justin Suntai Zainab Horan Holly York Mary 《Maternal and child health journal》2021,25(8):1345-1351
Maternal and Child Health Journal - Alcohol use during pregnancy is a critical public health issue that results in several adverse outcomes for both mother and child. While the prevalence of and... 相似文献
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Harry L. June Roger W. Hughes Holly L. Spurlock Michael J. Lewis 《Psychopharmacology》1994,115(3):332-339
Recent work in our laboratory demonstrated that Ro15-4513, a partial inverse benzodiazepine (BDZ) agonist, decreases ethanol (ETOH) self-administration in rodents under fluid deprivation conditions. The present study further examined the effects of Ro15-4513 (2.5 and 5.0 mg/kg) alone and in combination with Ro15-1788, (flumazenil) (8.0 and 16.0 mg/kg), a BDZ receptor antagonist on ETOH self-administration in freely feeding and drinking rats. Animals were trained to consume ETOH (11% v/v) using a limited access procedure. Measurements were taken at 10- and 60-min intervals. Ro15-4513 (2.5 and 5.0 mg/kg) markedly attenuated ETOH consumption at both intervals. The antagonistic actions of Ro15-4513 were completely blocked by the higher dose of flumazenil at both intervals; the lower dose failed to antagonize the Ro15-4513-induced reduction of ETOH intake. When flumazenil was given alone, both doses reduced ETOH self-administration at 60 min; although the magnitude of the antagonism was comparable to that of Ro15-4513 only with the highest does of flumazenil (16.0 mg/kg). Neither Ro15-4513 nor flumazenil alone or in combination significantly altered water intake at any of the tested doses. Rats pretreated with Ro15-4513 showed a substantial reduction in blood ethanol concentration (BEC) compared with the Tween-80 vehicle condition at the 10-min interval. However, the BEC of animals given Ro15-4513 in combination with flumazenil were similar to rats given Tween-80 vehicle. The present study extends our previous research by demonstrating that Ro15-4513 and flumazenil attenuate ETOH self-administration in non-food or water deprived rats. These studies suggest that the suppressant effects of Ro15-4513 and flumazenil on ETOH self-administration are associated with actions at the BDZ site of the GABAA receptor complex. These data are discussed in relation to the possible mechanism(s) by which Ro-15-4513 and flumazenil exert their antagonism on ETOH self-administration.Portions of this work were presented at the Annual Meeting of the Research Society on Alcoholism under the symposium entitled GABA/BDZ Receptor Update, Marco Island, FL, June 10, 1991.We would like to dedicate this paper to the late Dr. Richard G. Lister, a friend, teacher, colleague and exceptional scientist who contributed substantially to the area of alcohol abuse and alcoholism. Over the past years, Dr. Lister investigated the interactions of alcohol with inverse benzodiazepine agonists and benzodiazepine receptor antagonists. His seminal and more recent papers played an important role in delineating the GABA benzodiazepine systems in the neurobehavioral actions of alcohol. Richard, we will miss you. 相似文献
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Cholesteatoma epithelium is characterized by a dysregulation with a hyperproliferative growth and altered differentiation. In a variety of cells c-myc oncogene was found to be highly linked to the control of growth and differentiation. Expression of c-myc was studied in cholesteatoma epithelium using a monoclonal antibody directed against the 67 kDa c-myc protein product and the alkaline phosphatase-antialkaline phosphatase method. For quantitative analysis a computer-linked analyzing system was used. In contrast to normal skin, keratinocytes of basal and suprabasal layers showed nuclear staining in cholesteatoma epithelium. The extent of nuclear staining of epithelial cells in the cholesteatomas studied was significantly increased. Concurrent cytoplasmic staining was observed in both skin and cholesteatoma, but with a stronger reactivity in the latter. These findings suggest participation of the c-myc oncogene in cholesteatoma epithelium. 相似文献
48.
The insulin-like growth factor system in critical illness: pathophysiology and therapeutic potential
Insulin-like growth factor-I (IGF-I) mediates at least some of the anabolic actions of growth hormone (GH). Most IGF-I in the circulation is held in a 150 kD complex with IGF binding protein-3 (IGFBP-3). In critical illness there is GH resistance which results in low serum levels of IGF-I, although its bioavailability may initially be maintained by serum proteases which modify the IGFBP-3 and reduce its affinity for IGF-I. Attempts to treat the protein catabolism associated with critical illness by hyperalimentation have had only limited success. The use of recombinant human GH combined with nutritional support increases protein synthesis, but the GH resistance necessitates high doses and GH has adverse direct metabolic effects including insulin resistance and impaired glucose tolerance. Treatment with recombinant human IGF-I inhibits proteolysis but may cause hypoglycaemia if administered intravenously. Its effects are often transient and show tachyphylaxis. A combination of GH and IGF-I with nutritional support may be the most effective treatment to counter the catabolism associated with critical illness. The costs of such therapy could be offset by shorter hospital stays. Further controlled studies are necessary to establish the clinical effectiveness of growth factor treatment. 相似文献
49.
Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation. 相似文献
50.
We have tested a platelet aggregation inhibitor in the incubation fluid of deendothelialized fragments of the rat aorta and compared it with that of "intact" fragments. Some of the properties of the aortic inhibitor, and its effects on platelet adhesion to collagen fibrils, on platelet factor-3 (PF-3) availability, and on the activated partial thromboplastin time (APTT) and thrombin time (TT) were also evaluated in comparison with similar effects exerted by PGI2. We found that the incubation fluid of deendothelialized aortic samples contained inhibitor activity comparable with that of "intact" samples. The aortic inhibitor had similar properties to PGI2. The aortic inhibitor and PGI2 slightly inhibited light transmission changes of EDTA-PRP following exposure to collagen. However, scanning electron microscopy showed no appreciable difference in platelet adhesion to collagen fibrils. PGI2 and the aortic inhibitor inhibited Kaolin-induced PF-3 availability, but did not prolong the APTT or TT. 相似文献