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91.
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93.
RNA interference is a new approach to knockdown gene expression, but effectiveness varies depending on the organism, cell type or target sequence. Studies with Caenorhabditis elegans have shown that subsets of cells including neurons are often resistant to RNA interference. We measured RNA interference using green fluorescent protein reporter strains and feeding, soaking and injection delivery methods in a number of Caenorhabditis elegans neuron subtypes (dopaminergic, GABAergic, cholinergic, glutamatergic, touch). The sensitivity to RNA interference varied: GABAergic and dopaminergic neurons showed greater resistance while cholinergic, glutamatergic and touch neurons were more sensitive. Dysfunctional RRF-3, a putative RNA-directed RNA polymerase, had a significant effect on increasing neuron sensitivity in most subtypes. These results demonstrate that Caenorhabditis elegans neurons vary in their sensitivity to RNA interference. 相似文献
94.
目的通过训练大鼠急进高原模型从心肌组织形态和酶谱改变,研究训练对心肌损伤的防护。方法于海拔1520m实地环境设实验组(EG)采用中药抗疲I号加入常规饲料中喂养,对照组(CG)常规饲料喂养,EG、CG各40只游泳训练4周后,各选35只3h急进海拔3850m实地静息1.5h,从中各选10只作为静息对照采集标本,EG、CG各20只游泳至力竭后1h、24h采集标本;测定比较各组心肌酶谱指标等,镜下观察比较各组心肌形态变化。结果EG血中心肌酶谱指标1h、24h指标均优于CG1h、24h结果;心肌组织学结构从纵断面看,EG心肌结构清晰,肌丝细密,横纹清楚,核周无空隙;横断面心肌纤维群间隙小,毛细血管平均为10~12个/HPF;CG心肌纤维界限不清晰,肌丝分散,横纹不清楚,横断面心肌纤维群间隙增宽,毛细血管平均为3~5个/HPF,毛细血管腔扩张,红细胞堆积,提示有水肿。结论急进高海拔地区运动后可使心肌纤维缺氧水肿,血中心肌酶谱增高,同时会使心肌营养不良而发生结构改变,对心肌的供氧能力好坏必然决定运动能力强弱,过度训练、改变运动集训环境或强体力劳动均可引起心肌供血能力下降,本研究是通过抗疲I号加入食品干预训练大鼠的,有利于改善心肌营养与供氧状况,并能降低心肌纤维水肿发生。 相似文献
95.
AM Pierides HA Ellis H Dellagrammatikas JE Scott AW Norman 《Archives of disease in childhood》1977,52(6):464-472
Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy. 相似文献
96.
2种用药方案治疗慢性丙型肝炎的药物经济学评价 总被引:1,自引:0,他引:1
目的:评价2种用药方案治疗慢性丙型肝炎(CHC)的经济学效果。方法:185例CHC患者按照治疗方案的不同分为长效组(聚乙二醇干扰素α-2a联合利巴韦林)与普通组(普通干扰素α-2a联合利巴韦林),针对不同基因型分别采用最小成本分析法和成本-效果分析法进行研究,效果指标采用持续病毒学应答率(SVR),成本指标采用直接医疗服务成本。结果:对于基因2型、3型的CHC患者,长效组与普通组的SVR分别为76.5%、63.5%(P>0.05),治疗成本分别为30235.20、36950.40元(P<0.05);对于基因1型、未分型的CHC患者,长效组与普通组的SVR分别为52.9%、25.8%(P<0.05),成本-效果比分别为114310.77、143218.60,长效组相对于普通组的增量成本-效果比为86789.67。结论:从药物经济学角度看,聚乙二醇干扰素α-2a联合利巴韦林治疗CHC优于普通干扰素α-2a联合利巴韦林方案。 相似文献
97.
目的:观察携带目的基因的大鼠骨髓间充质干细胞(mesenchymal stem cells ,MSCs) 静脉移植在严重烫伤延迟复苏损伤体内的分布.方法:分离培养MSCs,用Ad-GFP转染MSCs,25只Wistar大鼠随机分为延迟复苏组(A组,10只)、即时复苏组(B组,10只)、假伤组(C组,5只).A、B两组大鼠背部造成Ⅲ度30%烫伤,制备A组为延迟复苏模型,B组为即时复苏模型,同时制备C组为假伤模型,经股静脉移植转染Ad-GFP 48 h后的MSCs.24 h,7 d后取小肠、肝脏、肾脏、烫伤皮肤创缘等组织,快速冰冻切片,荧光显微镜下观察在体内的分布.结果:MSCs 体外分离培养扩增5代,细胞数可达(1~2)×1011个,具有多态性和贴壁生长特性,MOI=100时,Ad-GFP转染MSCs效率可达86.4%.经股静脉移植24 h,在延迟复苏组烫伤皮肤组织创缘,小肠黏膜广泛可见绿色荧光,而在肝、肺等器官少见,即时复苏组荧光以烫伤皮肤创缘分布为主,小肠黏膜较少,假伤组中绿色荧光分布以肝脏为主.延迟复苏组小肠荧光强度明显强于即时复苏组和假伤组(P《0.05),而延迟和即时复苏组皮肤创缘荧光强度又强于假伤组(P《0.05).结论:导入目的基因可能不会改变MSCs归巢特性,并将为后续启动基因治疗烧伤延迟复苏后的损伤研究提供参考. 相似文献
98.
R E Brolin MD JH Gorman MD RC Gorman MD AJ Petschenik M D LJ Bradley MS RD HA Kenler PhD RP Cody Pb D 《Journal of gastrointestinal surgery》1998,2(5):436-442
Although iron, vltamm B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly
little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB)
patients Durmg a l0-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vltamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years,
then annually thereafter The principal objectives of this study were to determine how readily patients who developed metabolic
deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn
whether the risk of developmg these deficiencies decreases over time Hemoglobin and hematocrit levels were slgnificantly decreased
at all postoperative intervals in comparison to preoperative values Moreover, at each successive interval through 5 years,
hemoglobin and hematocrit were decreased signifiantly compared to the preceding interval Folate levels were significantly
increased compared to preoperative levels at all time intervals Iron and vltamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively Half of the low hemoglobin
levels were not associated with iron deficiency Taking multivltamin supplements resulted in a lower incidence of folate deficiency
but did not prevent iron or vitamin B12 deficiency Oral supplementation of iron and vitamin B12 corrected defiaencies in 43% and 81% of cases, respectively Folate deficiency was almost always corrected with multivitamins
alone No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anenua Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB Conversely, iron deficiency
and anemia are potentially serious problems after RYGB, particularly in younger women Hence we recommend prophylactic oral
iron supplements to premenopausal women who undergo RYGB 相似文献
99.
目的检测非小细胞肺癌(NSCLC)术后患者BAG-1、p53的表达,回顾分析其与患者临床特征及含铂方案化疗敏感性的关系,进一步探讨NSCLC的铂类耐药机制。方法应用免疫组织化学的方法检测125例NSCLC术后石蜡标本中BAG-1、p53的表达,随访后进行生存预后分析。结果BAG-1、p53在NSCLC组织中存在高表达(阳性率分别为64.8%和46.7%);BAG-1阳性、p53阴性患者具有生存优势(P〈0.05);BAG-1、p53表达阴性患者更能在含铂方案化疗后受益(P〈0.05)。结论BAG-1、p53与铂类药物化疗敏感性相关,可能成为新型的临床预后指标,有助于肿瘤个体化治疗方案的选择。 相似文献
100.
Fever and antipyresis in the lizard Dipsosaurus dorsalis 总被引:2,自引:0,他引:2