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971.
通过对小鼠补体受体Ⅱ型基因(CR2)进行定点突变,然后将野生型和突变型小鼠CR2/1(MCR2/1)及人CR2(hCR2)用电穿孔方法导入小鼠SP2/0进行表达,采用免疫组织化学等方法鉴定阳性细胞系。用EB病毒对转染阳性细胞进行感染,EBER-1杂交结果显示,仅转染hCR2和突变型MCR2(mtMCR2)的SP2/0细胞感染了EB病毒,前者感染EB病毒的阳性率较后者高很多。这为进一步研究EB病毒进入细胞的机制及建立EB病毒相关的鼻咽癌动物模型奠定了良好的基础。  相似文献   
972.
绝经后骨质疏松大鼠模型的综合评价   总被引:12,自引:0,他引:12  
利用双能X线骨密度仪、扫描电镜和骨生物力学试验综合评价大鼠去卵巢后的骨骼状况。结果显示:①大鼠卵巢切除后,活体、离体腰椎以及股骨(除R3区)、胫骨近端干骺端(R1区)的离体骨密度显著下降(P<0.01),离体L5和L6的骨丢失率最大,达13%;②骨小梁减少、变细,连接中断,骨小梁表面有吸收陷窝;③腰椎压缩强度和股骨力学性均下降,前者更明显,腰椎最大压缩力下降率达33.32%。提示:①类似于绝经后妇女,6月龄大鼠在卵巢切除4个月后骨量和骨质量均下降,特别在富含松质骨的部位,如腰椎、股骨远端等;②利用绝经后骨质疏松大鼠模型评价骨质疏松新药的有效性,应包括该新药对骨量、骨结构和骨强度的作用。  相似文献   
973.
目的:探讨大鼠中脑导水管周围灰质(PAG)内内源性强啡肽对神经降压素(NT)镇痛作用的影响。方法:以钾离子透入法引起大鼠甩尾反应的电流强度(mA)为痛行为反应的指标,观察向PAG内注入NT,抗神经降压素血清和抗强啡肽A1-13血清对动物痛阈的影响。结果:PAG内注入NT后,大鼠痛阈明显升高;注入抗神经降压素血清后,大鼠痛阈则明显降低,而注入抗强啡肽血清后,对NT的镇痛效应无显著影响,结论:PAG内NT在痛觉调制中发挥着重要的作用,且其作用不依赖于PAG内的内源性强啡肽。  相似文献   
974.
3T3—L1脂肪细胞中高糖诱导胰岛素抵抗的分子机制   总被引:2,自引:0,他引:2  
We investigated the cellular effect of high glucose using 3T3-L1 adipocytes on glucose transport activity, the expression of insulin signaling proteins and IRS1 tyrosine phosphorylation. Results showed that adipocytes treated with different high glucose (10, 15 and 25 mmol.L-1) for 24 hours showed to impair the basal and insulin-induced increase in glucose uptake in a dose-dependent manner and decreased significantly IRS1 tyrosine phosphorylation. High concentration of glucose produced opposite effects on IRS1 and IRS2: down-regulated IRS1 protein expression level and tightly up-regulated IRS2 contents. p85 and PKB were unaffected. Chronic exposure to high glucose can inhibit glucose uptake and induce insulin resistance. The mechanism may be involved in affecting the expression of insulin signaling peptides and tyrosine phosphorylation.  相似文献   
975.
应用放射免疫方法,对22例左向右分流型先天性心脏病合并肺动脉高压患者(肺高压组)及16例左向右分流先天性心脏病无肺高压患者(无肺高压组)体外循环心内直视手术围术期血浆内皮素水平进行了动态检测。结果发现:两者体外循环心内手术围术期血浆内皮素水平显著升高;无肺高压组术后血浆内皮素水平迅速下降并于手术后6h恢复至术前水平;肺高压组术后血浆内皮素水平下降缓慢,术后48h尚未恢复至术前水平。  相似文献   
976.
异丙酚小剂量咪唑安定联合镇静与胃镜检查   总被引:1,自引:0,他引:1  
OBJECTIVE: To search for a sedative method that is more suitable for gastroscopy. METHODS: All of patients were randomly divided into control group and experimental group. The experimental group was treated with propofol and midazolam, the control group was treated with propofol alone. The cumulation dosage of propofol, sedative effect, variation of BP and SaO2 were observed in all patient. RESULTS: The cumulative dosage of propofol in the experimental group was lower than that in the control group [(73.21 +/- 18.67) mg and (117.23 +/- 21.57) mg respectively]; the oblivious degree in the experimental group was higher than that in the control group (95.65% and 80.00%); the onset time and the descendant range of BP and SaO2 were also lower in the experimental than those in the control group. There was not remarkable difference in sedative effect and veriviscont time between the control group and the experimental group. CONCLUSIONS: In such a rapid operation of gastroscopy, the dosage of propofol in the experimental group is obviously less than that in the control group, while it does not affect the effect of sedation, the diagnose and cure time in gastroscopy room, and has more security and less cost.  相似文献   
977.
利用透射式电子显微镜观察小儿喘咳液对过敏性哮喘豚鼠肺超微结构变化情况。结果显示:连续雾化吸入卵清蛋白后第1d肺毛细血管壁充血并挤压毛细血管壁,第8d肺毛细血管壁增厚,胶原纤维增生。而用小儿喘咳液连续治疗7d后肺毛细血管壁增厚程度减轻,无胶原纤维增生。证明小儿喘咳液对哮喘有良好的治疗效果。  相似文献   
978.
Objective. To study the redistribution ofendothelin- 1 (ET- 1 ) receptors in two subcellular organelles, the sarcolemreal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced by cecal ligation and puncture (CLP). ET1 receptor was assayed by using[125I]-ET1 binding. Marker enzyme activities, protein yield, and dry-to-wet weight ratio of cardiac membraneswere measured. Results. Septic rat heart exhibited two distinct phases: an initial hyperdynamic phase( 9h after CLP; early stage of sepsis) followed by a hypodynamic ( 18h after CLP, late stage of sepsis) phase. [125I]-ET1 binding study showed that during early stage of sepsis, the Bmax of ET1 receptors was increased by 30% in sarcolemma but decreased by 19% in light vesicles, while during late stage of sepsis, the Bmax was decreased by 24% in sarcolem-ma but increased by 38% in light vesicles. The total binding of sarcolemma and light vesicles was increased by 25% during early stage of sepsis but decreased by 17% during late stage of sepsis. Conclusions. These data indicated that ET1 receptors in the rat heart were externalized from light vesicles to sarcolemmal membranes during early hyperdynamic phase while internalized from surface membranes to intracellu-lar compartment during late hypodynamic phase of sepsis.  相似文献   
979.
Objective. To review our preliminary experience and evaluate our early results of a combined intraopemtive iliac angioplasty and stenting with infrainguinal revascularization in multilevel atherosclerotic occlusive disease. Methods. From July 1999 to April 2000, intraoperative iliac angiOplasty and stenting combined with simultaneous femoro-pepliteal bypass were pedormed on 12 lower extremities of 10 patients suffering from multilevel athemsclemtic occlusive disease. There were 8 men and 2 women, average 72 years. The indicationsf or procedures included disabling claudication in 3 and rest pain in 7 patients. Results. Eleven iliac angioplasty and stem procedures combined with simultaneous 9 femoro-popliteal by-pass and 3 femoro-femoral-popliteal bypass were performed in 12 limbs of 10 patients. Angioplasty and stem placement was technically successful in all patients. One contralateral femoral-popliteal bypass was failure after femoro-femoral-popliteal bypass. There were no additional instances of procedural or postoperative morbidity or mortality. Mean follow-up was 5 months (range 1 -10 months). During the follow-up period, one femoro-infrapoplitealgraft became occluded after 7 months and above-knee amputation was required. The cumulative primary patencyrate of stented iliac arteries, femoro-femoral bypass grafts and femoro-popliteal bypass grafts were 100% (11/11), 100% (3/3) and 90. 9% (10/11) in the follow-up period, respectivdy. The amputation rate was 8. 3%(1/12). Conclusions. Intraoperative iliac artery PTA and stent placement can be safely and effectively pedormed simultaneously with infrainguinal revascularization for multilevel atherosclerotic occlusive disease by skilled vascular surgeon, using a portable C ann fluoroscopy in the operating room. Furthermore, iliac artery PTA and stenting was valuable adjunct to distal bypass either to improve inflow and outflow, or to reduce the extent of traditionalsurgical intervention, and also, any angioplasty and stenting-related complications can be immediately corrected as well.  相似文献   
980.
AT2R转染表达促进人肾间质纤维母细胞凋亡   总被引:2,自引:1,他引:1  
目的 探讨血管紧张素Ⅱ(AngⅡ)2型受体(AT2R)基因表达对人肾间质纤维母细胞凋亡的影响。方法 构建带AT2R基因的重组复制缺陷型腺病毒载体(AdCMV-AT2R),转染培养的人肾间质纤维母细胞,用流式细胞仪检测AT2R细胞表达率,RT-PCR方法检测AT2R,bcl-2和bax mRNA表达,肾间质纤维母细胞凋亡用流式细胞仪、原位末端标记法检测。结果 构建的AdCMV-AT2R转染培养肾间质纤维母细胞表达率为90.6%。AT2R峰值表达时,其凋亡发生率较末转染组增加3.2倍(P<0.01),bax表达增加76.3%(P<0.05),bcl-2则无明显变化,TUNEL检测结果表明转染组出现大量凋亡细胞。结论 AT2R转染表达可显著增加体外培养肾间质纤维母细胞的凋亡,这对延缓肾间质纤维化是有益的。  相似文献   
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