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211.
目的探讨稳定、可靠建立神经干细胞体外增殖的方法,并对增殖培养的细胞进行鉴定。方法获取胚胎大鼠的脑组织,通过加入神经生长因子和采用保留细胞联系技术操作,使脑组织中的神经干细胞在体外克隆增殖并稳定传代。以免疫荧光方法对增殖克隆的神经干细胞球进行鉴定。结果神经干细胞不断增殖形成神经干细胞球且神经干细胞能快速稳定传代增殖。培养的细胞为神经干细胞特异性巢蛋白(nestin)染色阳性细胞。结论在神经生长因子的作用下,利用保留细胞联系技术操作,神经干细胞可以在体外快速、稳定克隆增殖并传代。  相似文献   
212.
目的:探讨经尿道等离子前列腺双极汽化电切术(TUPKVP)治疗前列腺增生的效果。方法:回顾性分析580例良性前列腺增生(BPH)患者行TUPKVP的临床资料。结果:中转开放手术2例,切除前列腺组织10~80 g,平均32.5 g。手术时间25~150 min,平均60 min,术中输血10例,无电切综合征(TURS)发生。术后随访2~36个月,患者最大尿流率升高,IPSS症状评分值降低,排尿通畅,疗效好,并发症少。结论:TUPKVP出血少,手术安全,疗效确切,是治疗前列腺增生的有效方法。  相似文献   
213.
To improve the drug permeation into and/or across the skin, essential oils extracted from Alpinia oxyphylla (AO) were evaluated using in vitro and in vivo permeation techniques with Wistar rats as the animal model. Hydrocarbons and oxygenated sesquiterpenes were the major components in the lower-polarity fraction (AO-1) and higher-polarity fraction (AO-2), respectively. Permeation of indomethacin was significantly enhanced after treatment with AO-1 and AO-2 in the in vitro and in vivo studies. AO-2 generally showed a higher ability to promote drug permeation compared to AO-1. The increment of skin/vehicle partitioning may be the predominant mechanism for this enhancing activity. Both transepidermal water loss (TEWL) and colorimetric evaluation showed limited irritation to skin by AO essential oils at the macroscopic level. Human skin fibroblasts were used to investigate the in vitro screening of skin toxicity. AO-1 slightly increased prostaglandin E(2) (PGE(2)) formation from skin fibroblasts. A striking result was observed with AO-2, which greatly inhibited the release of PGE(2). Moreover, both AO essential oils had no statistically significant effect on PGE(2) release by human lung epithelial cells. The results of this study indicate that skin disruption and inflammation do not necessary correspond to the enhancing efficiency of the enhancers tested.  相似文献   
214.
PURPOSE: To examine the relationship between ametropia and optical aberrations in a population of 200 normal human eyes with refractive errors spanning the range from +5.00 to -10.00 D. METHODS: Using a reduced-eye model of ametropia, we tested the hypothesis that the optical system of the eye is uncorrelated with the degree of ametropia. These predictions were evaluated experimentally with a Shack-Hartmann aberrometer that measured the monochromatic aberrations across the central 6 mm of the dilated pupil in well-corrected, cyclopleged eyes. RESULTS: Optical theory predicted, and control experiments on a model eye verified, that Shack-Hartmann measurements of spherical aberration will vary with axial elongation of the eye even if the dioptric components of the eye are fixed. Contrary to these predictions, spherical aberration was not significantly different from emmetropic eyes. Root mean square of third-order aberrations, fourth-order aberrations, and total higher aberrations (third to 10th) in myopic and hyperopic eyes were also uncorrelated with refractive error. Astigmatic eyes tended to have larger total higher-order aberrations than nonastigmatic eyes. CONCLUSIONS: We conclude that a reduced-eye model of myopia assuming fixed optical parameters and variable axial length is not tenable.  相似文献   
215.
Repeated measures of wavefront aberrations were taken along the line-of-sight of seven eyes using two instruments: an objective, cross-cylinder aberroscope (OA) and a Shack-Hartmann (SH) aberrometer. Both instruments were implemented on the same optical table to facilitate interleaved measurements on the same eyes under similar experimental conditions. Variability of repeated measures of individual coefficients tended to be much greater for OA data than for SH data. Although Zernike coefficients obtained from a single measurement were generally larger when measured with the OA than with the SH, the averages across five trials were often smaller for the OA. The Zernike coefficients obtained from the two instruments were not significantly correlated. Radial modulation-transfer functions and point-spread functions derived from the two sets of measurements were similar for some subjects, but not all. When average Zernike coefficients were used to determine optical quality, the OA indicated superior optics in some eyes, but the reverse trend was true if Zernike coefficients from individual trials were used. Possible reasons for discrepancies between the OA and SH measurements include difference in sampling density, quality of data images, alignment errors, and temporal fluctuations. Multivariate statistical analysis indicated that the SH aberrometer discriminated between subjects much better than did the objective aberroscope.  相似文献   
216.
几种中草药复配杀虫剂的急性毒性实验研究   总被引:1,自引:1,他引:0  
为有效开发植物杀虫剂资源及今后的推广应用提供科学依据。用两种粉剂和两种醇剂的杀虫应用浓度给小白鼠灌,而家兔则行皮肤刺激试验。结果显示,除醒剂Y-13经口有中毒情况发生外,其它3种制剂均无中毒现象,醇剂Y-13的家兔皮肤也无刺激反应发生。作者认为:4种制剂在有杀虫效果的前提下,杀虫应用浓度对人和动物都较安全。有开发和推广应用价值。  相似文献   
217.
煤工尘肺结核的生存分析   总被引:5,自引:0,他引:5  
对116例煤工尘肺结核住院病例的生存研究结果表明,5年、10年和15年生存率分别为71.14%、58.97%、43.56%,明显低于该矿的尘肺患病人群的生存率。经COX模型分析结果提示:终检时年龄、接尘年代、最初合并结核时的尘肺期别、细菌学情况、合并肺心病、气胸为影响本组尘肺结核患者远期生存的危险因素,相对危险度分别为0.82、0.83、0.61、2.55、1.49、1.68,为尘肺结核的防治提出有指导意义的见解。  相似文献   
218.
目的探讨胎盘早期剥离(胎盘早剥)的产前诊断和处理。方法对我院近10年发生的13例胎盘早剥作回顾性分析。结果妊高征及慢性高血压病占本组病因的46.2%。本组围产儿死亡率为23.08%,孕产妇死亡率为0。子宫卒中发生率46.15%,产后出血30.77%,DIC 7.70%。阴道出血、腹痛、胎心异常或消失、血性羊水为主要临床表现。产前诊断率为46.15%,B超检出率为60%。结论胎盘早剥的诊断需结合患者临床表现、发病诱因、B超检查结果全面考虑,确诊后应尽快终止妊娠。  相似文献   
219.
目的 通过对24例阴道肿瘤患者的B超声像图分析,总结B超诊断阴道肿瘤的方法。方法 收集24例1995~2002年,我院门诊及住院患者的病史资料及声像图,结合病理结果分析声像图特征,并与病理加以对照。结果 24例患者声像图表现为囊性、实质性、囊实性肿瘤。结论 通过对声像图的分析,探讨了B超诊断阴道肿瘤的可行性、声像图特征及该方法的局限性。  相似文献   
220.
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.  相似文献   
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