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991.
Fifty-five patients with vascular insufficiency resulting in above-knee (AK) and through-knee (TK) amputations were studied to determine factors related to prosthetic candidacy and functional outcome. Chart review showed that the only difference between patients who were fitted with prostheses and those who were not fitted with prostheses was their respective number of medical complications. Twenty-three of 31 patients with prostheses were evaluated 7 to 35 months after receiving the prostheses. Ten (44%) of these patients wore their prostheses all day every day and used wheelchairs minimally or not at all. Over half of the patients evaluated used their wheelchairs most of the time. Two (9%) of the 23 patients had stopped wearing their prostheses. Patients who demonstrated increased walking distances and velocities at follow-up used their prostheses more and their wheelchairs less than did the other patients. Neither gait factors nor hip range of motion at discharge was predictive of continued prosthetic use. Functional outcome and prosthetic use were limited in this group of elderly patients with dysvascular AK and TK amputations. The results of this study may serve as a basis for clinical determination of prosthetic candidacy and functional goals.  相似文献   
992.
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation.  相似文献   
993.
Trichinosis is a rare cause of a neck mass, but should be considered by the physician when contemplating a differential diagnosis. This disease is still endemic in parts of the world and is directly related to the ingestion of incompletely cooked pork. A case is presented in which a 68-year-old man was diagnosed as having a squamous cell carcinoma of the mandible only to have trichinosis diagnosed on the final pathologic report. The case presentation is followed by a historical review and discussion.  相似文献   
994.
A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH.  相似文献   
995.
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985.  相似文献   
996.
二乙酰二脱水卫矛醇对小鼠白血病L1210细胞增殖的影响   总被引:5,自引:0,他引:5  
目的 研究二乙酰二脱水卫矛醇 (1 ,2 :5 ,6 dianhydro 3 ,4 diacetylgalactitol,DADAG)的抗脑白血病作用及机制。方法 用小鼠脑内移植瘤模型、MTT法、DNA掺入法、流式细胞仪和Westernblot法 ,观察DADAG对小鼠脑内移植瘤和体外白血病L1 2 1 0 细胞的作用 ,并探讨作用机制。结果 DADAG对DBA/ 2小鼠脑内移植白血病L1 2 1 0 有明显的抑制作用 ;对体外白血病L1 2 1 0 细胞同样有很强的抗增殖作用 ,其IC50 值为 2 4 6mg·L- 1 。DADAG不可逆地抑制L1 2 1 0 细胞内DNA的生物合成。DADAG 2 4mg·L- 1 处理L1 2 1 0 细胞 6h后 ,细胞发生G2 /M周期阻滞 ,2 4h后达最高峰。细胞周期素B1 蛋白水平在DADAG处理 2 4h后开始下降 ,而磷酸化的细胞周期依赖性激酶CDK1在DADAG处理 6h后开始上调 ,并呈时间依赖性。结论 DADAG的抗脑白血病作用与其抑制白血病细胞的增殖密切相关  相似文献   
997.
艾灸对30例健康人甲皱微循环及血液流变学的影响   总被引:3,自引:0,他引:3  
郭瑞林  赵宁侠  任秦有  张周良  李斌 《医学争鸣》2002,23(12):1112-1114
目的:探讨艾灸对健康人甲皱微循环及血液流变学的影响。方法:选择健康学员及武警战士各30例,年龄20-22岁,应用江苏协达公司生产的XDM-1型微循环电脑检测仪及北京世帝科学仪器公司生产的LG-R-80血液粘度计,LG-B-190型红细胞变形/聚集测试仪。固定专人操作,分别于艾灸前及艾灸后,测试甲皱微循环及血液流变学各项指标的变化。结果:艾灸八邪及三阴交穴后,甲皱微循环各项指标均有明显变化,经统计学处理,红细胞聚集程度、血流速度、流态积分、管周积分均有显著性差异(P<0.05),其余各项指标虽有不同程度的改变,但无统计学意义(P>0.05);血液流变学各项指标亦有明显变化,经统计学处理,全血低切相对粘度、全血低切还原粘度、红细胞刚性指数、红细胞聚集指数及血浆纤维蛋白原都有非常显著性差异(P<0.01),全血高切相对粘度有显著性差异(P<0.05),其余各项指标虽有不同程度的改变,但无统计学意义(P>0.05)。结论:艾灸八邪及三阴交穴后可明显改善红细胞聚集程度,降低血液粘度,加快血流速度,降低外周血管阻力。  相似文献   
998.
Delayed graft function (DGF) in cadaver kidney transplants is a common problem and is often due to acute tubular necrosis (ATN). DGF in transplants may have a deleterious effect on long-term graft survival. Since thyroid hormone has been shown to hasten recovery from ATN in experimental models, we designed a trial to determine if a defined course of triiodothyronine (T3) would improve the short- or long-term outcome of patients with DGF in cadaveric transplants. A prospective, randomized, placebo controlled, double blind trial of T3 was carried out in patients with DGF in cadaveric renal transplants. End-points were percentage requiring dialysis, percentage recovering function, time to recovery and length of hospital stay. Long-term outcomes were percentage grafts functioning at 1 year and mean serum creatinine at 1 year. Forty-four patients were randomized to receive either T3 or placebo. Three patients were dropped from each group when early biopsies disclosed that DGF was due to rejection. The groups were well matched by age, cold ischemia time of the graft, and percentage reactivity to a random panel of antigens. Baseline thyroid function studies, including T3, reverse T3 (rT3), and thyroid stimulating hormone (TSH) levels, were similar between the two groups and typical of 'euthyroid-sick syndrome'. T3 had no effect on percentage requiring dialysis, time to recovery, percentage recovering function, or length of stay. At 1 year follow-up, graft function was similar in both groups and significantly lower than that seen in patients with good initial function. Thyroid hormone, given early in the course of DGF in cadaver kidney recipients, had no effect on the course of DGF. Long-term graft function is impaired in patients who experience post-transplant DGF compared to those who have good initial function.  相似文献   
999.
1000.
It has been demonstrated that total parenteral nutrition (TPN) modulates the function of the hepatic reticuloendothelial system (RES). The objective of this study was to evaluate the impact of two different TPN lipid emulsions on the recovery of allograft RES function after orthotopic liver transplantation (OLTx). In a prospective, double-blind study, OLTx patients were randomly assigned to two treatment groups. Group I ( n=13) received a TPN regimen that included long-chain triglycerides (LCT). Group II ( n=9) received a TPN regimen that included a fat emulsion consisting of both medium-chain triglycerides (MCT) and LCT. At baseline, i.e., on days 2 or 3 after OLTx ( t1), before lipids for TPN were started, hepatic RES function was determined using the human serum albumin millimicrosphere technique (K-value, 1/min). A second measurement ( t2) was obtained after 7 days of TPN, including one of the study's two fat emulsions. The mean (+/- SD) K-value (1/min) was 0.48+/-0.16 in the LCT group and 0.55+/-0.28 in the MCT/LCT group at t1, and it improved to 0.62+/-0.21 in the LCT group and to 0.86+/-0.32 in the MCT/LCT group at t2. RES function recovery was significantly better in the MCT/LCT group ( P< or = 0.05). MCT/LCT emulsion appears to be the TPN fat emulsion of choice after OLTx as it seems to have less impact on hepatic RES recovery.  相似文献   
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