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21.
中国汉坦病毒H82O5株G2糖蛋白基因的克隆及在真核细胞中的瞬时表达 总被引:2,自引:1,他引:1
从感染病毒乳鼠脑组织提取总RNA,采用RT-PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中,通过脂质体介导转染COS-7细胞,用SDS-PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2-pcDNA3.1/His重组表达质粒,表达产物的相对分子量为56ku,与理论预期大小一致,并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2-pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有,能在哺乳动物细胞中表达并具有抗原性,重组质粒可应用于汉坦病毒的DNA疫苗研究。 相似文献
22.
23.
李松林副主任医师将肾小球肾炎的病机概括为湿、热、毒、瘀、虚等方面,在中医辨证的基础上,结合现代医学对其病因和发病机理的认识及中草药药理作用,针对不同的病理机制和临床表现,提出清热解毒法,活血化瘀法,调补脾肾法,扶正固本法,并视症有机结合,恰当治疗,疗效显著。 相似文献
24.
Effect of impact exercise on bone mineral density in elderly women with low BMD: a population-based randomized controlled 30-month intervention 总被引:4,自引:3,他引:1
Raija Korpelainen Sirkka Keinänen-Kiukaanniemi Jorma Heikkinen Kalervo Väänänen Juha Korpelainen 《Osteoporosis international》2006,17(1):109-118
Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest. 相似文献
25.
足底深支或(和)第一跖背动脉逆行足背岛状皮瓣的临床应用 总被引:4,自引:0,他引:4
目的探索足部远端软组织缺损修复的较佳方法。方法采用足底深支或(和)第1跖背动脉逆行足背岛状皮瓣对6例足部远端软组织缺损创面进行修复。结果6例患者均一次性修复,软组织缺损最大面积8cm×6cm,术后随访1~4年,足部功能与外观均较满意。结论足底深支或(和)第1跖背动脉逆行足背岛状皮瓣血管解剖比较恒定,操作简单,是修复足远端软组织缺损的较好方法。 相似文献
26.
目的:通过对日本大耳兔双光气肺损伤后肺泡Ⅱ型细胞内磷脂和形态学变化的观察,探讨双光气对肺Ⅱ型细胞的损伤及其机制.方法:将纯种日本大耳白兔35只随机分为对照组(n=10)、染毒即刻组(n=5)、染毒2h组(n=5)染毒4h组(n=5)、染毒8h组(n=5)、染毒12h组(n=5);采用浓度一时间法动态式染毒,染毒后按不同时间点对实验动物进行颈总动脉插管放血处死,取肺并用肺灌洗液对支气管肺泡进行灌洗,然后取肺组织作冰冻切片,进行电镜观察,并测定细胞内磷脂含量.结果:肺Ⅱ型细胞内磷脂含量在染毒即刻开始时较正常组含量下降(P<0.01);在染毒2h时降到最低,之后上升(P<0.05),而在4h后又下降(P<0.05).染毒终止后,损伤逐渐加重,染毒后2h磷脂因消耗而降低.染毒后4h,由于代偿功能启动,磷脂短暂升高,出现致伤性代偿期.从染毒2h后开始,细胞损伤加重,磷脂合成进入失代偿期,合成逐渐减少.到染毒后8h,肺泡Ⅱ型细胞内细胞处于致伤性和致死性细胞改变的临界点,细胞出现致死性改变,磷脂合成、分泌停止,细胞出现死亡.结论:兔在双光气染毒12h内,肺泡表面活性物质磷脂的改变有差异,随细胞损伤程度发生改变,出现明显中毒分期:即致伤性改变期、致伤性代偿期、致伤性失代偿期、致死性改变期. 相似文献
27.
A case of ultrastructurally confirmed myoepithelioma of the breast studied by fine-needle aspiration biopsy is reported. Aspirated tumor cells were spindle-shaped with well-defined cytoplasm and oval nuclei showing no remarkable nuclear pleomorphism. They were seen mainly in irregular bundles with strong cellular cohesiveness. Their cytoplasm contained S-100 protein demonstrated by the peroxidase antiperoxidase staining technique. 相似文献
28.
Robbert-Jan Roozeman Lasse Murtomäki Kyösti Kontturi 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,575(1):9-17
A recently introduced setup to measure the dynamic interfacial tension of expanding drops was used to compare the adsorption behaviour of a series of lipids at the electrified water∣dichloroethane interface. Phospholipids with saturated carbon chains of different length (DMPC, DPPC, DSPC, DAPC, DBPC), an unsaturated phospholipid (DOPC) and an ethanolamine (DSPE) were compared. It was found that the adsorption decreases with increasing chain length. Also, the increase of the flow rate reduces the degree of adsorption effectively. On the timescale of the experiments, the DSPE, DAPC and DBPC adsorption showed no potential dependence, whereas the adsorption of DOPC was stronger than that of the saturated lipids. Adsorption was modelled using the Langmuir adsorption isotherm; the potential dependence of adsorption is discussed. 相似文献
29.
花生四烯酸和二十二碳六烯酸对海马神经细胞生长发育的影响 总被引:2,自引:0,他引:2
【目的】观察不同浓度花生四烯酸 (AA)和 (或 )二十二碳六烯酸 (DHA)对体外培养海马神经细胞生长发育的影响。【方法】无血清培养液中分别加入不同剂量的AA和 (或 )DHA ,采用噻唑蓝比色试验 (MTT法 )反映各组海马神经细胞存活状况 ,神经元特异性烯醇化酶 (NSE)染色鉴定神经细胞 ,图像分析技术测量神经细胞的胞体大小和突起长度。【结果】培养液中分别添加AA为 4~ 8μmol/L、DHA为 2~ 8μmol/L时 ,神经细胞活力高于对照组 ;当培养液中AA和DHA总浓度为 4μmol/L、比例为 2∶1或 4∶1时 ,神经细胞的活力、胞体面积、最大长径、最大短径和平均突起长度均显著高于单一添加 4μmol/LAA、4μmol/LDHA和对照组。【结论】AA、DHA均具有促进体外培养海马神经细胞生长发育的作用 ;与单独添加AA、DHA相比 ,AA和DHA共同作用的促海马神经细胞生长发育作用更好。 相似文献
30.
Hideya Ohnishi Kazuyoshi Nishihara Keiyoshi Tamae Shoshu Mitsuyama Ryuji Abe Satoshi Toyoshima Eiji Abe 《Surgery today》1996,26(11):929-932
Granular cell tumors (GCT) are rare neoplasms, and only 173 cases of benign GCT of the breast have been documented. We report herein the cases of two patients with this tumor and discuss the methods of diagnosis and treatment. The first patient was a 60-year-old woman who presented with a firm ill-defined mass in her left breast. Mammography showed a dense shadow with spicula and skin thickness, and ultrasonography revealed a hypoechoic mass with an irregular border. Radical mastectomy was performed under the wrong preoperative diagnosis of breast cancer. The second patient was a 31-year-old woman who presented with an elastic-hard mass in her left breast. Mammography showed a well-demarcated dense mass, and ultrasonography revealed a well-defined hypoechoic mass with a large depth-width ratio. Fine-needle aspiration cytology (FNAC) showed a large number of histiocytic cells with abundant granular cytoplasm. An excisional biopsy was performed, and histological examination confirmed a diagnosis of GCT. GCT is benign, but often misdiagnosed as breast cancer both clinically and radiologically. Therefore, histological examination is essential for making a correct diagnosis, while FNAC is also useful. Local resection is still the treatment of choice, and surgeons should do their utmost to avoid performing needless radical mastectomy. 相似文献