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121.
血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响   总被引:4,自引:0,他引:4  
目的为探讨血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响。方法应用培养的乳鼠心肌细胞造成缺血再灌注损伤的动物模型,观察心肌细胞中超氧化物岐化酶(SOD)的水平,推断细胞内活性氧的生成量;观察培养液中乳酸脱氢酶(LDH)活性改变以判断细胞损伤情况;并进行DNA琼脂糖凝胶电泳及末端脱氧核苷酸介导的脱氧尿苷三磷酸缺口末端标记法(TUNEL),以判断细胞死亡类型及程度。结果血府逐瘀汤可显著升高缺血再灌注时SOD的水平,显著降低LDH的水平。DNA电泳图谱表明:血府逐瘀汤可使DNA的拖尾基本消失;TUNEL显示血府逐瘀汤可显著减少缺血再灌注所致的心肌细胞死亡。结论血府逐瘀汤有保护缺血再灌注时心肌细胞免于死亡之功效。  相似文献   
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As a test of the applicability of modern bioengineering tools to pediatric surgery, we developed by computer-aided design (CAD) methods and evaluated a virtual reality (VR) model of laparoscopic pyloromyotomy (LP) and created a set of retractable hook instruments, called Pylorohooks. Our VR model of LP incorporated the infant's body wall, stomach, and hypertrophied pylorus as well as laparoscopic cannulas and two Pylorohooks. CAD software was used to design the 3-mm-diameter, retractable, double-pronged, minimally-traumatic hook instrument. A rapid prototype processor was employed to create a plastic model of the instrument. Surgical-grade stainless-steel prototypes were then manufactured and used in actual LPs. A working VR model was achieved. Following an initial correction in the angulation of the hooks, the instruments were successfully employed in nine consecutive LPs in infants weighing from 3.4 to 5.7 kg. VR and CAD thus proved instrumental in the development of a new LP approach. Because of increasing pressure to limit human and animal experimentation, computer-based bioengineering methods offer promising alternatives that are clearly applicable to pediatric surgery. Accepted: 13 March 2001  相似文献   
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PURPOSE: This study examined the effects of brief written educational materials on osteoporosis-related knowledge, beliefs, and behaviors. The study also examined whether observed effects varied as a function of one's stage in the precaution adoption process. DESIGN: The study used an experimental research design. SETTING: Participants were identified from North Carolina driver's license records. SUBJECTS: Of the 1476 women in the initial sample, 536 (36.3%) enrolled in the study and 307 completed all follow-up assessments. INTERVENTION: Participants were randomly assigned to one of four groups. One group received an information packet containing general information about osteoporosis. One group received an action plan packet containing instructions on how to increase one's level of exercise and calcium intake. One group received both packets. The final group received neither packet. MEASURES: Primary study variables were beliefs related to osteoporosis, calcium, and exercise; osteoporosis knowledge; calcium and exercise stage; calcium intake; and exercise level. RESULTS: Overall, receipt of the information packet was associated with changes in knowledge and beliefs (F[18,283] = 2.11, p < .01) irrespective of participants' stage of change. No effects on behavior were observed. CONCLUSIONS: These findings suggest that brief written educational materials can facilitate knowledge and belief change but that they do not promote behavior change. The generalizability of these findings is limited by the low study response rate.  相似文献   
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As yet, there is no reported study of chromosome allele loss in fibrolamellar carcinoma (FLC), a distinct, rare variant of hepatocellular carcinoma (HCC). We searched for evidence of allele loss in FLC using 18 DNA probes for 10 chromosomes and compared the pattern of loss with our series of HCC. Two of the probes, lambda MS32 (1q42-43) and cMS621 (5p) showed allele losses in one tumour, while other probes showed no loss. The frequency of allele loss in FLC was much lower than in HCC, which may be associated with their different prognoses.  相似文献   
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Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
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Summary Between January 1977 and January 1990, 44 patients with symptomatic vascular rings/slings required surgical intervention at this center. Nineteen patients had double aortic arch (group I); 13 patients had vascular ring consisting of right aortic arch, anomalous origin of the left subclavian artery, and ligamentum arteriosus (group II); eight patients had innominate artery compression (group III); and four patients had pulmonary artery sling (group IV). Three patients had complex congenital heart defect and died secondary to it and are excluded from the study. Follow-up was obtained on 31 patients (76%). The follow-up period ranged from 0.4 years to 10.9 years, with a mean of 3.6 years. Seventy percent of the overall group were asymptomatic, and 30% of patients continued to have upper and lower respiratory symptoms on late follow-up. One third of patients in groups I and II, who underwent surgical repair, continue to have symptoms. Patients who have persistent symptoms should be further evaluated with PFTs, MRI, and bronchoscopy, and may benefit from aortopexy. Patients with innominate artery compression and pulmonary artery sling do well soon after surgery with relief of most of their symptoms.  相似文献   
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