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991.
血管内皮生长因子165反义RNA治疗人脑胶质瘤的实验研究   总被引:8,自引:0,他引:8  
目的 探讨应用血管内皮生长因子165(VEGF165)反义RNA治疗人脑胶质瘤的可行性。方法 构建和鉴定反义VEGF165真核表达载体;将其转染入人脑胶质瘤细胞SHG44,检测其转染前、后的生物学性状;比较转染前、后SHG44细胞的裸鼠皮下致瘤性;分别应用免疫印迹、免疫组织化学、微血管计数、电镜和流式细胞仪检测上述改变。结果 成功构建反义VEGF165真核表达载体并在SHG44细胞获得表达,该细胞  相似文献   
992.
阿法骨化醇对去卵巢大鼠骨质疏松症防治作用的实验研究   总被引:9,自引:2,他引:7  
目的 探讨从骨量、骨结构、骨力学和骨转换等方面研究阿法骨化醇对去卵巢大鼠骨质疏松症的防治作用。方法 53只健康雌性未交配6个月龄Wistar大鼠分为6组(1)基线组(Base)6个月龄时处死;(2)假手术组(Sham);(3)去卵巢(OVX)治疗前对照组(OVXb);(4)OVX治疗末对照组(OVXe);(5)OVX后雌激素治疗组(O+E);(6)OVX后阿法骨化醇治疗组(O+VD)OVX后6周开  相似文献   
993.
情感性精神障碍事件相关电位变异与自杀行为史的相关性   总被引:3,自引:0,他引:3  
探讨情感性精神障碍患者件相关电位变异的临床意义。方法收集39例抑郁相和22例躁狂相患者,以33例正常人为对照组,记录其事件相关电位P300和CNV。结论P300和CNV临床应用价值得到初步证实,自杀行为相关的生物学指标研究中需进一步重视。  相似文献   
994.
The epidemiological survey of prevalence of NIDDM (non-insulin dependent diabetes mellitus) and IGT(impaired glucose tolerance) was conducted among 9450 residents aged 25-70 in some areas of Hubei Province, China. The results show that NIDDM and IGT prevalences are 2.62% and 4.48%, respectively. There is no significant difference between male and female (P > 0.05). The NIDDM prevalence in cities is slightly higher than that in countryside, but the difference is not significant (P > 0.05). However, the IGT prevalence in city is significantly higher than that in countryside (P < 0.01). The prevalence of both NIDDM and IGT is increasing along with the age of the population. It is also significantly related to the family history of NIDDM, hypertension, and high body mass index (BMI). By using stepwise logistic regression to analyse the risk factors of NIDDM, age (OR = 1.86), BMI(OR = 2.69), family history (OR = 2.84) and hypertension (OR = 2.23) entered the model (significance level is alpha = 0.05).  相似文献   
995.
The dose-effect of adaptive response of thymocyte apoptosis and cell cycle progression induced by whole-body X-ray irradiation (WBI) was studied in male Kunming mice. The inductive doses (D1) were 25, 50, 75, 100 or 200 mGy 6 h before the challenging doses (D2) of 1.0, 1.5 or 2.0 Gy. The changes in the percentages of the thymocyte apoptotic bodies (TAB) and the cells in different phases of cell cycle were measured with flow cytometry. The percentages of TAB decreased, the arrests of G1 and G2 + M phases diminished, and the cells of DNA synthesis of S phase increased when the D1 + D2 groups was compared with the D2 groups. When D1 was 200 mGy, the adaptive response of thymocyte apoptosis and cell cycle progression were no longer induced by low dose radiation (LDR). In addition, the extracellular fluid from the splenocytes were cultured with Con A for 48 h in vitro 24 h after 75 mGy WBI was placed in the murine thymocyte suspension from mice irradiated with 2.0 Gy WBI and co-incubated. The thymocyte apoptosis decreased. Especially, noteworthy was that the percentages of TAB after the incubation for 72 h were significantly lower than those in 2.0 Gy irradiated thymocytes (P < 0.05). These results indicate that when the mice were irradiated with 25-100 mGy (D1, 12.5 mGy/min) 6 h before 1.0-2.0 Gy (D2, 0.287 Gy/min) exposure, an adaptive response of thymocyte apoptosis and cell cycle progression may be induced under the condition of WBI, and LDR (75 mGy) may change the microenvironment of immune cells and decrease the thymocyte apoptosis.  相似文献   
996.
Cadmium(Cd),one of the most dangerous heavy metals,has a very similar ionic radius to calcium(Ca),The interference of cadmium in calcium homeostasis may play an important role in cadmium toxicity.Recent reports indicate that calmodulin(CaM) inhibitors such as trifluoperazine and chlorpromazine(CPZ) could protect rodents against cadmium toxicity,It was also reported that pretreatment of mice with zine(Zn)could reduce the adverse effects induced by cadmium.The aim of this study is to determine whether Cd changes the balance of other essential metals such as Zn and copper(Cu) in rat tissues,and whether CPZ can reverse these changes which are induced by cadmium intoxication.Adult male Sprague-Dawley(SD) rats were injected intraperitoneally(ip) with cadmium chloride(CdCl2)(0.2,0.4,0.8mg Cd/kg body wight) alone and 0.4mg Cd/kg in association with CPZ(5mg/kg) daily for a week.The control animals were injected with normal saline only.The results showed that the cadmium content in the liver,kidney,and testis increased significantly with a dose-response relationship.Cadmium treatment markedly increased the Zn and Ca content in some of the tissues,Hepatic and renal metallothionein(MT) increased significantly after cadmium intoxication,CPZ treatment,howerver,reduced cadmium content in liver,but not blood and kidney.CPZ seemed to decrease the content of MT in liver and significantly increase the amounts of MT in kidney.These data suggest that the intervention of cadmium with tissue essential metals may play a role in cadium toxicity in rats,and calmodulin inhibitors to some extent can reduce the adverse effect of cadmium by decreasing the cadmium load in tissues and reversing the unbalance of essetial metals.  相似文献   
997.
用RT-PCR技术从人胎盘组织内成功地扩增全长肝细胞生长因子(HGF)cDNA基因(2 184bp),并将其克隆至pGEM-T载体,经限制性核酸内切酶NdeⅠ,BglⅡ,HindⅢ,BamHⅠ和XhoⅠ的酶谱分析和DNA测序分析证实。再将其亚克隆至逆病毒载体pLNL-XHC,可进一步用于基因表达和基因治疗的研究。  相似文献   
998.
目的:探讨肾细胞癌中FHIT基因的改变及意义。方法:用RT-PCR及Southern印迹杂交法检测肾细胞癌及其细胞系中FHIT基因转录本,并观察其基因组的改变。结果:约8.3%(2/24)肾细胞癌有异常转录本;其中一株细胞系cDNA在用外引物扩增时,只有一个变小的FHIT基因异常转录本;用内引物扩增时,FHIT基因转录本完全缺失。约20%(5/24)肾细胞癌FHIT基因区域的基因组DNA出现重排。  相似文献   
999.
中药“拮新康”对白血病细胞凋亡的影响   总被引:2,自引:0,他引:2  
为探讨中药“拮新康”对白血病细胞凋亡的影响。采用形态学及DNA凝胶电泳方法观察其对白血病细胞株HL-60及K562细胞凋亡的影响,结果示:①电镜观察可见凋亡细胞和凋亡小体,DNA凝胶电泳可见典型的梯形带改变;②一定浓度范围内的拮新康经适当作用时间后可诱导白血病HL-60,K562细胞凋亡,但诱导K562细胞凋亡所需时间较HL-60长且剂量较大。提示拮新康可诱导白血病细胞凋亡,与剂量和时间有一定的关  相似文献   
1000.
采用近年来对急性心肌损伤诊断有高度特异性和敏感性的血清标记物——心脏肌钙蛋白T(cTnT)来判断缺血顸处理对心肌缺血再灌注损伤的影响。选择风湿性心脏病瓣膜置换术患者32例,随机分为顸处理组(实验组)和对照组。两组在疾病种类、术中升主动脉阻断及转流时间等方面无明显差异,分别测定术前,术后4h,2,4h及72h血清cTnT含量。结果显示。缺血顸处理组不但降低术后血清cTnT升高的峰值,而且使cTnT的含量较快地恢复至正常水平。提示缺血预处理对心脏缺血再灌注损伤有一定的保护作用。  相似文献   
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