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61.
rhTPO 对60Co 照射小鼠造血系统影响的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的为了检测TPO的体内活性及其对血小板减少的治疗作用,寻找用以治疗辐射及化学药物等所致骨髓损伤造成的血小板减少与缺乏,缓解临床上的出血症状,降低死亡率的一种新途径。方法本实验应用基因工程的方法重组了人的TPO,取昆明种正常雄性,经一次5.0Gy60Coγ射线全身照射小白鼠为动物模型,通过对外周血血象的观察,及小鼠骨髓造血祖细胞培养的检测,研究了rhTPO在体内对60Co全身照射处理小鼠的造血系统的影响。结果实验表明,rhTPO能够减轻照射对小鼠外周血血小板及骨髓造血祖细胞中巨核系祖细胞的影响,并有促进其早期恢复的作用,且这种作用是量效相关的。结论提示,TPO是巨核细胞系统较特异的正调控因子,具有促进巨核细胞增殖发育和刺激血小板生成的作用,是临床治疗骨髓组织损伤引起的血小板减少和缺乏及贫血的有希望的生物治疗药物。  相似文献   
62.
82例高血压患者16项人格特质测验   总被引:1,自引:0,他引:1  
研究目的应用卡特尔16项人格特质测验探讨原发性高血压患者的人格特征。研究背景高血压病是危害人类健康的常见病之一,发病率逐年上升,但其病因至今尚未阐明,故有必要从心理、人格方面来探讨高血压的发病原因,以利于高血压病的防治。研究方法本文对82例均由2名以上内科医师确诊为原发性高血压、且现在高压仍保持在20/12.7kPa以上的患者进行卡特尔16项人格特质测验,并与78例人群对照分析。结果高血压患者在C-稳定性、E-峙强性、Q-紧张性以及在双重人格因素类型中的适应与焦虑方面与正常对照组有显著差异(P<0.05)。结论心理-社会因素是促使高血压发生的重要因素,它对高血压病因的阐明有重要意义,同时也使我们越来越重视运用心理、行为疗法,如生物反馈、各种松驰疗法等去防治高血压。  相似文献   
63.
Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.  相似文献   
64.
Toluene in blood as a marker of choice for low-level exposure to toluene   总被引:1,自引:1,他引:0  
The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels.  相似文献   
65.
Summary Twenty-two persons (20 men and 2 women) were examined for their external and internal exposure to the glycol ether 1-methoxypropan-2-ol (PGME) during the production, leak testing and mounting of brake-hoses. For the measurement of external exposure, personal air monitoring was the method of choice. Average concentrations of PGME of 82.2 mg/m3 (22.3 ppm), 68.6 mg/m3 (18.6 ppm) and 11.3 mg/m3 (3.1 ppm) were found in the air of the brakehose production, leak test and mounting areas, respectively. For the estimation of internal exposure to PGME, this glycol ether was measured in both urine and blood. The biological samples were taken post-shift. The highest internal exposure levels were found in the brakehose production section and in the leak test area. The average post-shift concentrations for PGME in workers in the brakehose production section were 4.6 mg/l in urine and 13.5 mg/l in blood; the corresponding figures for workers in the leak test area were 4.2 mg/l in urine and 11.0 mg/l in blood. In blood and urine samples of workers engaged in the mounting area, PGME levels were below the detection limits. The elimination kinetics of PGME were also studied in three highly exposed persons, and mean excretion half-lives of PGME of approximately 4.4 h were found. On the basis of our results we made a rough calculation of a future biological tolerance value: we would except that concentrations of 38-109 mg per litre of blood and 10–31 mg per litre of urine would correspond to the German MAK value for PGME (375 mg/m3).  相似文献   
66.
As patterns of family formation change, it is important to know how children's lives are affected by their parents' marital and socioeconomic circumstances. Using data from the 1993 Kenya Demographic and Health Survey, this study shows that children of never married and formerly married mothers have significantly higher probabilities of polio dropout and acute undernutrition than those of monogamously married mothers. The number of male household members of working age greatly enhances the chances of full immunization and the nutritional status of children whose mothers were previously married. For children of never married mothers, the benefits of residing with males of working age are largely a function of ethnicity. The results also show that, although children are not disadvantaged nutritionally when their fathers have more than one wife, polygyny is associated with a higher probability of polio dropout and lower probability of full immunization than monogamy. Higher socioeconomic status is associated with a greater probability of full immunization and a lower probability of malnutrition but socioeconomic factors do not explain the effects of mothers' marital status. The findings underscore the complex realities of family interaction and the importance of the broader social context in accounting for variations in child welfare across diverse marital situations.  相似文献   
67.
刘贤铭 《药学进展》2003,27(6):365-368
[目的]了解肿瘤用药的消费现状及发展趋势,为临床合理用药提供依据。[方法]对本院1996年-2002年抗肿瘤药、生物反应调节剂和升白细胞药的用药情况进行统计分析,以药品的年消耗金额作统计。[结果]抗肿瘤药、生物反应调节剂和升白细胞药分别占全部药品年消耗总金额的24.24%~33.73%、15.80%~23.33%和5.86%~9.11%。[结论]抗肿瘤药、生物反应调节剂和升白细胞药是用于肿瘤治疗的主要药品,尤其是抗肿瘤天然药物有着广阔的应用前景。  相似文献   
68.
Objective To establish a colorectal cancer colostomy orthotopic transplantation mice model. Methods A colostomy was preformed in BALB/C nu-nu nude mice. After two weeks, when the stoma healed, tumor tissues developed from Lovo cells were implanted into the submucosa of the stoma. When tumor grew up to 5 nun, fluorouracil(5-FU, 20 mg/kg) was administrated by intraperitoneal injection. Tumor developed at the colostomy was observed and its biological characteristics and behaviour were evaluated. Results Colostomy was performed in 10 mice and stoma healed at two weeks. Ten colostomies developed detectable tumor in two to three weeks. Three to five weeks later, the tumors grew up to 5 mm. Survival time of mice injected with 5-FU was (15.2±3.7) weeks (ranged: 11-21 weeks), and the survival time of the no-treantment group was (12.3±2.8)weeks (ranged:9-19 weeks). The difference was statistically significant (P=0.001). The rate of mesenteric metastasis was 1/5 and 2/5 in the treatment and no-treatment group respectively. Conclusion Colostomy orthotopic transplantation mice model is an ideal mice model with the advantages of having high success rate, visualization of implanted tumor in living animal, long survival time and significant tumor response to common chemotherapeutic agent.  相似文献   
69.
温州市艾滋病流行特征及流行趋势分析   总被引:1,自引:1,他引:0  
目的 分析温州市1985~2000年HIV/AIDS流行现状及影响因素,为采取有效控制措施提供依据。方法 分析全市的艾滋病监测及实验室资料。结果 1985年发现首例HIV抗体阳性,至2000年底累计发现感染者124例,发病27例,死亡16例。感染者以青壮年为主,男女比例为3.28:1,静脉推注吸毒和性接触是主要传播途径。结论 预计今后几年温州市高危人群中HIV感染者将大幅度增长,必须采取有效措施预防和控制艾滋病。  相似文献   
70.
目的了解自愿戒毒的海洛因依赖者的个性心理特征及其对脱毒后复吸的影响。方法使用MMPI对30例自愿戒毒的海洛因依赖者和30例未对任何药物成瘾的正常人的个性心理特征进行对照分析,明确海洛因依赖者个性心理特征,在此基础上找出个性心理特征与复吸原因的联系。结果海洛因依赖者在MMPI各量表中诈病(F),精神病态(Pd),疑病症(Hs),偏执狂(Pa),精神分裂(Sc)等量袁与对照组有明显的差异,且这些差异与脱毒者复吸原因有着直接的关系。结论海洛因依赖者的个性心理特征为明显的反社会行为和社会适应障碍,对自己健康过分关注,缺乏对社会环境的归属感,易将自己的问题合理化而归因于剐人,并由这种心理特征增加了复吸率。  相似文献   
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