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71.
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   
72.
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   
73.
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   
74.
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   
75.
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   
76.
妇科腹腔镜手术中转开腹原因分析   总被引:2,自引:1,他引:1  
邓国义  林虹 《中国内镜杂志》2007,13(12):1321-1322
目的探讨妇科腹腔镜手术中转开腹的原因。方法对1234例妇科腹腔镜手术中的中转开腹患者的病情进行总结分析。结果16例腹腔镜中转开腹患者中,盆腔严重粘连者7例,盆腔恶性肿瘤4例,其他5例。结论盆腔严重粘连和盆腔恶性肿瘤是妇科腹腔镜手术中转开腹的主要原因,术前、术中充分的病情评估可能有助于减少中转开腹的发生。  相似文献   
77.
HLA-B27相关的前葡萄膜炎眼后节并发症的临床特点   总被引:1,自引:0,他引:1  
目的探讨HLA—B27阳性的前葡萄膜炎眼后节并发症的临床特点及治疗。方法2002年1月至2005年10月就诊的前葡萄膜炎患者采用流式细胞术进行外周HLA-B27的检测,筛选出71-例82眼HLA-B27阳性前葡萄膜炎患者,分为两组:实验组为眼后节受累的患者24例31眼,对照组为眼后节未受累的患者47例51眼。另有HLA—B27阴性前葡萄膜炎患者74例116眼作参考。所有患者均进行裂隙灯、眼底镜等常规眼科查体,部分行眼底荧光血管造影。分析了HLA—B27相关的前葡萄膜炎眼后节并发症的临床特点。采用x^2检验及t检验进行统计学分析。结果71例82眼HLA—B27阳性前葡萄膜炎中有24例31眼占37.8%出现眼后节并发症者,包括:黄斑囊样水肿12例15眼占48.4%,视乳头水肿7例8眼占25.8%,而玻璃体炎最多见为21例27眼占87.1%,8例10眼占32.3%患者存在两种或两种以上的眼后节表现。74例116眼HLA—B27阴性者有8例12眼占10.3%有眼后节表现。实验组中发生前房成型纤维素渗出31眼中18眼占58.06%和积脓31眼中9眼占29.03%明显高于对照组(前房纤维素渗出51眼中3眼,5.88%,X^2=27.56,P〈0.01;前房积脓51眼中1眼,1.96%,X^2=13.20,P〈0.01);实验组中伴发相关全身性疾病24例中有16例占66.67%的几率高于对照组(47例中有17例,31.66%,X^2=5.94,P〈0.05)。出现眼后节并发症的患者经全身及局部应用糖皮质激素治疗,31眼中有11眼最佳矫正视力≥1.0。结论HLA-B27阳性前葡萄膜炎易出现眼后节并发症,HLA—B27相关的前葡萄膜炎眼后节受累的患者发生相关全身性疾病和前房纤维素渗出与积脓的几率较高。  相似文献   
78.
A 9-month-old male infant had generalized diffuse blue-gray pigmentation over most of his body, sparing the scalp, face, neck, palms, soles, periumbilical area, genital area, and nipples. Within the lesion, there were several conspicuous macules of considerably darker hue. Histologic examination revealed numerous dermal melanocytes. By 16 months of age, the child's blue-gray pigmentation had decreased substantially.  相似文献   
79.
In order to find out anti-platelet activating factor (PAF) from natural resources, Korean medicinal plants used for the treatments of peripheral circulation disorders were tested for their possible protective effects on PAF-induced anaphylactic shock. From the above screening, the methanol extract ofGentiana scabra showed a potent antagonistic activity against PAF. Water suspension of the extract was partitioned with CH2Cl2 and EtOAc, successively. The EtOAc fraction which showed the highest activity was chromatographed on silica gel to yield 6 fractions. From the fraction which showed higher PAF-antagonistic activity than the other fractions, compound1 was isolated by recrystallization. On the basis of spectral data, compound1 was identified as 2-hydroxy-3-methoxybenzoic acid glucose ester. The compound prevented the mice from the PAF-induced death at a dose of 300 μg/mouse.  相似文献   
80.
对1997年以来423例病态喉的频闪喉镜表现进行分析,结果显示声带有病理改变者其粘膜波、振幅、闭合相、运动周期性、对称性均有不同程度的变化,这种变化能直接反映声带病变的深度及范围,对喉部疾病的诊断、鉴别诊断、治疗指导及预后评价具有重要意义.  相似文献   
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