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991.
目的 研究凝血酶、TNF-α、IFN-γ等对U937细胞表达uPAR mRNA的影响,观察凝血系统、炎症介质与纤溶功能变化间的关系。 方法 建立并应用逆转录PCR(RT-PCR)法测定培养U937细胞的uPAR mRNA。 结果:1.经测定批间变异系数(CV间)确认了RT-PCR法测定uPAR mRNA的稳定性;2.以不同浓度凝血酶刺激24h,对U937细胞表达uPAR mRNA有抑制和促进两种不 相似文献
992.
新生儿严重脑室内出血连续腰穿的疗效 总被引:16,自引:0,他引:16
目的为了治疗和预防脑室内出血后脑积水的发生和发展,改善新生儿严重脑室内出血的不良预后。方法1989年以来,对19例在出生后早期经头颅B超诊断为严重脑室内出血(IVH)患儿进行了连续腰穿(LP)治疗。结果有效16例,自动出院1例,失败2例。有效率为84.2%。有效16例初次LP日龄为14.6±5.7d,疗程23.4±12d,平均LP次数9.3±4.7次,平均LP间隔期3.1±1.6d,平均每次放液量6.7±2ml,LP治疗后起效天数为10.1±7.8d。2例在连续LP的同时联用乙酰唑胺治疗亦取得显著疗效。16例平均随访月龄为3.2±1月,体格发育均正常,B超显示12例脑室形态正常,4例脑室呈稳定的轻度增大。失败的2例初次LP迟,初期LP间隔期延长为7-9d,放液量<5ml。同期另有17例严重IVH患儿未予LP治疗。其中4例并发脑积水,5例自动出院,4例早期死亡,余4例其后脑室形态稳定。结论连续LP不失为治疗新生儿严重IVH实用安全有效的方法,LP疗效欠佳时可联用乙酰唑胺治疗。 相似文献
993.
R M van Dam Z Huang E B Rimm M A Weinstock D Spiegelman G A Colditz W C Willett E Giovannucci 《American journal of epidemiology》1999,150(5):459-468
The authors examined the relation of constitutional factors and sun exposure to risk of basal cell carcinoma of the skin (BCC) in a prospective cohort of 44,591 predominantly Caucasian US male health professionals, 40-75 years of age and free of cancer at enrollment in 1986. During 8 years of follow-up, 3,273 cases of self-reported BCC were documented. The following variables were each associated with an elevated risk of BCC: having red hair; green, hazel, or blue eyes; a tendency to sunburn; and north European ancestry. The lifetime number of blistering sunburns was also positively associated with BCC risk (p trend < 0.0001). Compared with men who as teenagers had been outside less than once a week, men who had been outside weekly (relative risk (RR) = 1.30; 95% confidence interval (CI): 1.14, 1.47) and daily (RR = 1.42; 95% CI: 1.24, 1.63) had an elevated risk of BCC. Living in a region of residence with high solar radiation as an adult was also associated with an increased risk of BCC (RR = 1.48; 95% CI: 1.36, 1.60), whereas living in such a region only in childhood did not increase BCC risk. These results confirm the role of constitutional factors and suggest that adult sun exposure increases BCC risk. 相似文献
994.
Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan 总被引:7,自引:0,他引:7
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Guo YL Lin YC Sung FC Huang SL Ko YC Lai JS Su HJ Shaw CK Lin RS Dockery DW 《Environmental health perspectives》1999,107(12):1001-1006
This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan. 相似文献
995.
Jasmine green tea epicatechins are hypolipidemic in hamsters (Mesocricetus auratus) fed a high fat diet. 总被引:3,自引:0,他引:3
P T Chan W P Fong Y L Cheung Y Huang W K Ho Z Y Chen 《The Journal of nutrition》1999,129(6):1094-1101
These studies were designed to test the hypolipidemic activity of green tea epicatechins (GTE) isolated from jasmine green tea. In Experiment 1, three groups of hamsters were given a semisynthetic diet containing 200 g lard/kg and 1 g cholesterol/kg for 4 wk. The control group received distilled water, and the other two groups received either 15 g/L green tea water extract (GTWE) or 5.0 g/L GTE solution. Both the GTWE and GTE groups had lower concentrations of serum total cholesterol (TC) and triacylglycerols (TG) than the controls (P < 0.05). In Experiment 2, four groups of hamsters received tap water as the drinking fluid, but they were given the same high fat and cholesterol diet supplemented with 0 (control), 1.1, 3.4 or 5.7 g GTE/kg diet. The hypolipidemic effect of jasmine GTE was dose dependent. In Experiment 3, the time-course of changes in serum TC and TG was monitored in hamsters given the high fat diet supplemented with 5.7 g GTE/kg in comparison with that of controls. The hypolipidemic effects of dietary GTE were evident after feeding for 2 wk. Dietary supplementation of GTE did not affect liver fatty acid synthase. However, GTE-supplemented hamsters had higher fecal excretions of total fatty acids, neutral sterols and acidic sterols compared with the control group. In Experiment 4, hamsters were fed nonpurified diet; the control group drank distilled water, and the GTE group drank distilled water containing 5.0 g GTE/L. No differences in activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and intestinal acyl CoA:cholesterol acyltransferase were observed. This study suggests that the hypolipidemic activity of GTE is not due to inhibition of synthesis of cholesterol or fatty acid but is most likely mediated by its influence on absorption of dietary fat and cholesterol. 相似文献
996.
Association between indoor and outdoor air pollution and adolescent asthma from 1995 to 1996 in Taiwan 总被引:2,自引:0,他引:2
The study aim was to estimate the contribution of indoor and outdoor air pollution to the 1-year prevalence of adolescent asthma after personal susceptibility and other potential risk factors were taken into account. A large-scaled cross-sectional study was conducted among 165,173 high school students aged 11 to 16 years in the different communities of Kaohsiung and Pintong in Taiwan, from October 1995 to June 1996. Each student and his/her parents participating in the study completed a video and a written International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire about symptoms of wheezing and allergies, passive smoking, and demographic variables. After adjustment for potential confounders, adolescents exposed to cigarette smoking (odds ratio = 1.29, 95% confidence interval (CI), 1.17-1.42) and environmental tobacco smoke (odds ratio = 1.08, 95% CI, 1.05-1.12) were found to suffer from asthma at an increased frequency. We observed a statistically significant association between outdoor air pollution and asthma, after controlling for potential confound variables. Total suspended particulate, nitrogen dioxide, carbon monoxide, ozone, and airborne dust particles all displayed an independent association with asthma, respectively. There were no selection biases in this community-based study, which provides evidence that passive smoking and long-term, high average outdoor air pollution are independent risk factors of asthma. 相似文献
997.
In Drosophila, dorsal-ventral polarity is determined by a maternally encoded signal transduction pathway that culminates in the graded nuclear localization of the Rel protein, Dorsal. Dorsal is retained in the cytoplasm by the IkappaB protein, Cactus. Signal-dependent phosphorylation of Cactus results in the degradation of Cactus and the nuclear targeting of Dorsal. We present an in-depth study of the functional importance of Dorsal phosphorylation. We find that Dorsal is phosphorylated by the ventral signal while associated with Cactus, and that Dorsal phosphorylation is essential for its nuclear import. In vivo phospholabeling of Dorsal is limited to serine residues in both ovaries and early embryos. A protein bearing mutations in six conserved serines abolishes Dorsal activity, is constitutively cytoplasmic, and appears to eliminate Dorsal phosphorylation, but still interacts with Cactus. Two individual serine-to-alanine mutations produce unexpected results. In a wild-type signaling background, a mutation in the highly conserved PKA site (S312) produces only a weak loss-of-function; however, it completely destabilizes the protein in a cactus mutant background. Significantly, the phosphorylation of another completely conserved serine (S317) regulates the high level of nuclear import found in ventral cells. We conclude that the formation of a wild-type Dorsal nuclear gradient requires the phosphorylation of both Cactus and Dorsal. The strong conservation of the serines suggests that phosphorylation of other Rel proteins is essential for their proper nuclear targeting. 相似文献
998.
Procedures for studying the dynamic response of the occupant within a rear-end impacted vehicle are presented. Most of the researches in the impact analysis were performed by experimental approach and this costs a lot of time and money. Especially, the repeatability is very hard to produce in a destructive condition. Most of all, the analytic parameters can be investigated are limited by the experimental approach. By using numerical techniques, this research employs Kane's equation and Huston's method to develop a simulated system with visual graphic output to observe the rear-end impact response. According to the simulated results, at a constant seatback angle the maximum acceleration values of head and chest increased with the increasing of impact velocity. Furthermore, at a constant impact velocity the relative rotation angle of a passenger's head to chest decreased with the increasing of initial seatback angle. 相似文献
999.
A nerve growth factor from the venom of Chinese cobra (Naja naja atra) and its effects on male reproductive system in rats 总被引:1,自引:0,他引:1
Xu TR Wang WY Huang YH Meng QX Li DS Lu QM Xiong YL 《Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology》1999,124(2):149-156
A nerve growth factor (NGF) was isolated from the venom of Chinese cobra (Naja naja atra) by ion exchange chromatography, gel filtration and fast protein liquid chromatography (FPLC). The N-terminal sequence of 22 amino acid residues was identical with other NGFs previously purified from the venom of the same genus. The NGF monomer molecular weight was estimated to be 13,500 by reducing SDS-PAGE and the isoelectric point was determined to be 7.2 by isoelectric focusing electrophoresis. NGF improved the epididymal sperm motility of male rats and increased the pregnancy rate and fetus number of mated female rats. The serum levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) of male rats administrated NGF + gossypol was lower than that of male rats administrated gossypol. Histological sections of testes and epididymides showed that NGF reduced the destructive effects of gossypol on rat testes. 相似文献
1000.
用免疫组化SP法对63例喉鳞状细胞癌的PCNA和C-erbB-2进行原位检测,并随访了5年的生存情况。结果表明,PCNA指数越高,病理分级越差(P<0.01),5年生存率越低(P<0.05),颈淋巴结转移率越高(P<0.05)。而C-erbB-2表达阳性率与病理分级、5年生存率及颈淋巴结转移率无关。PCNA和C-erbB-2之间无相关性。提示PCNA指数与喉癌恶性程度、5年生存率、颈淋巴结转移率密切相关,在喉癌中检测PCNA较C-erbB-2更有意义。 相似文献