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991.
为了寻找能够控制硝普钠释放的控释膜,研究了数种高分子膜的通透性,其中以经过热处理的聚乙烯醇(PVA)膜控制硝普钠释放性能较好。进一步研究了热处理条件对PVA膜通透性的影响,发现只要热处理的温度和时间恰当,就可以获得具有一定通透性的PVA膜。 相似文献
992.
Jeffrey R. Rubin MD Enrique Labadie MD Gary Anderson BS James Persky MD Jerry Goldstone MD 《Annals of vascular surgery》1988,2(2):127-132
This study evaluates the effect of blood volume and hematocrit changes on brain tissue during temporary global ischemia. Normal saline was administered intravenously to 55 gerbils to achieve hypo-, normo-, and hypervolemic hemodilution and uniform 30% hematocrit reduction. Each group had unilateral carotid artery ligation and temporary (20 minute) contralateral carotid occlusion. After ten days or death, brains were harvested, preserved in formalin, sectioned in a manner which provided adequate samples of both cortex and hippocampus, and stained with H&E and luxol fast blue. They were then examined and staged microscopically for white and gray matter infarction, edema, and neuronal injury and loss. Histologic studies were performed in a randomized and blinded manner and were classified by one of four categories: normal, minimal, moderate, and severe changes. Three of ten (30%) controls survived ten days but had severe neuronal loss, minimal cerebral edema and a minimal to moderate number of white matter strokes. Survival was best in animals treated with hypovolemic hemodilution (43%). Other rates were: normovolemic (33%), controls (30%), and hypervolemic (8.3%). The degree of brain tissue damage was markedly less in the normovolemic group. In this model, normovolemic hemodilution followed by hypovolemic hemodilution offered the best overall cerebral protection during global ischemia. 相似文献
993.
994.
KEVIN R. BISHOP MSN ARNP MOLLY DOUGHERTY Ph D ARNP RUTH MOONEY Ph D ARNP PHYLLIS GIMOTTY Ph D BRADFORD WILLIAMS MD 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1992,21(5):401-406
OBJECTIVE: To examine factors that affect pelvic muscle response to 12 weeks of pelvic muscle exercise. DESIGN: Repeated measures design in which intravaginal pressures during pelvic muscle contractions were recorded at baseline and after four exercise levels. SETTING: College of Nursing research site in Gainesville, Florida. PARTICIPANTS: Eighty-five parous, community-dwelling women, aged 35-78 years and without incontinence as a primary concern. INTERVENTIONS: A 12-week graded program of regular (three times per week, every other day) pelvic muscle exercise at home. MAIN OUTCOME MEASURES: The hypotheses were that younger age, lower parity, higher baseline intravaginal pressures, and adherence to the pelvic muscle exercise program each would result in significant improvement in maximum intravaginal pressures. RESULTS: The only factor showing significance in predicting a successful outcome was age (t = -2.29, df = 41, one-tail probability = .0136). CONCLUSIONS: Regular, graded exercise over several weeks is needed to build pelvic muscles, and some women who exercise do not improve. Although the reasons for not improving are unclear, age is a significant factor. 相似文献
995.
C Lynn Van Antwerpen MD Sidney M Gospe Jr MD PhD Nancy A Wade MD 《Pediatric neurology》1988,4(6):379-380
A 12-year-old girl developed a reversible myeloradiculopathy 1 week after a wasp sting. Delayed neurologic hypersensitivity reactions to Hymenopteran stings occur primarily in adults. Reactions involving both the peripheral and central nervous systems are extremely rare and have never been reported in a child. The mechanisms underlying this uncommon reaction may be related to age-dependent differences in immunologic responses. 相似文献
996.
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient. 相似文献
997.
998.
5名电离辐射事故患者外周血T细胞T细胞抗原受体、T细胞分化抗原决定簇-3效应的研究 总被引:1,自引:0,他引:1
文中报道了5名事故性急性骨髓型放射病患者照后2.5和3.5年外周血T淋巴细胞T细胞受体(TCR)基因,TCR、T细胞分化抗原决定簇-3(CD_3)表达与TCR/CD_3复合物功能的辐射效应.发现5名患者于照后2.5年,2名(5.2Gy和2.4Gy,55岁)于照后3.5年外周血T细胞应答抗CD3单抗刺激而增殖的能力尚未完全恢复;经同时用IL-2和抗CD_3单抗刺激,增殖能力比单用抗CD_3单抗刺激有所增强;后2名的外周血TCR、CD_3阳性细胞百分率一直低于正常对照和其他患者;并见一患者出现DNA重排杂交带型.本文并从TCR/CD_3在介导T细胞抗原刺激反应中的作用,电离辐射对TCR/CD_3复合物的影响,后果和意义等方面进行了讨论. 相似文献
999.
作者曾经体外实验证明,均聚寡脱氧胞嘧啶核苷酸片段(dC14)有抗病毒活性,现继续研究其在体内的作用。不给dC14的对照组小鼠,接种腹水瘤细胞后:100%发病和死亡,潜伏期为6d,存活期11d;给每只小鼠dC14 1.3~3.2 mg,发病率和死亡率降低至20%,疾病潜伏期和存活期推迟。在未经dC14处理的种瘤细胞和淋巴组织与经处理的淋巴组织中,多聚酶链反应(PCR)法都检测到病毒核酸,而正常小鼠中则无此种病毒核酸顺序。研究结果提示,dC14对小鼠SRS腹水瘤的发病和生长有抑制作用。此种抑制作用可能是通过抑制病毒基因的表达来实现的。 相似文献
1000.
M. Ninkovi MD D. uur B. Starovi S. Markovi 《The Journal of hand surgery, European volume》1992,17(6):657-659
AV fistulae are extremely rare complications after hand replantation. In the case presented, the formation of an AV fistula did not occur immediately after the replantation, but after the insertion of the free lateral arm flap to the extensor surface of the replanted hand. This paper discusses the mechanisms responsible for the formation of AV fistulae. 相似文献