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51.
目的:探讨抗青光眼餐引流术后的白内障患眼进行超声乳化吸除术的手术入路,操作方式及临床效果。方法:避开功能性滤过泡,选择角巩膜隧道切口或透明角膜切口,瞳孔麻痹性散大时,做一个完美的直径约5mm的连续环形撕囊以补偿之;恰当处理虹膜后粘连后,在病理性小瞳孔下完成超声乳化手术;眼压失控者行青光眼白内障人工晶体植入三联术。结果:无后囊破裂,人工晶体全部囊袋内植入,术后1周视力≥0.5者20只眼(64.5%),0.1-0.4者8只眼(25.8%),<0.1者3只眼(9.7%)。随访1-16个月,眼压均在20.55mmHg以下。结论:体外流术后的白内障患眼,超声乳化手术因其切口小,并发症少,不破坏功能性滤过泡,不损伤瞳孔,是目前各种手术方法中的最佳选择。  相似文献   
52.
The morphology and distribution of dopaminergic interplexiform cells in adult rat and monkey retinas were analyzed to determine any correlation with the function of dopamine in the outer retinal layers. The retinas were processed as whole mounts for tyrosine hydroxylase immunohistochemistry. There was a network formed by the sclerally directed processes of interplexiform cells in the inner nuclear, outer plexiform, and outer nuclear layers running throughout the retina. Their density was higher in the superior retina than in the inferior retina of the rat and was especially high in the superior temporal quadrant. The external network in this quadrant was significantly less dense in the monkey than in the rat, as are the interplexiform cells. The somata of interplexiform and other dopaminergic cells were about the same size in both rats and monkeys. Computer-assisted reconstruction of external arborizations of individual cells showed that external processes lay very close to horizontal and photoreceptor cells and also to blood capillaries. Because they were long, thin, and highly varicose; branched at right angles; and often arose from an axon hillock, the external processes were identified as axons. Therefore, we define the dopaminergic interplexiform cells as multiaxonal neurons, with at least one outwardly directed axon that reaches the outer plexiform layer. The function of the network of external processes from the interplexiform dopaminergic cells is discussed in terms of modulating the release of dopamine to external layers.  相似文献   
53.
新型隐球菌L型的诱导与形态学观察   总被引:1,自引:0,他引:1  
在高渗液体培养基中,以溶菌酶400~3200μg/ml,二性霉素B0.39~6.25μg/ml,去氧胆酸钠0.06~0.50%均可诱导出新型隐球菌L型。以二性霉素B纸片法或人胆汁也可诱导成功。各方法的诱导结果有些不同。新型隐球菌L型的共同特征为:(1)革兰氏染色性改变;菌体淡染,或呈革兰氏阳性颗粒状,或呈革兰氏阴性圆球状。(2)菌体大小不一,呈圆形、丝状或不规则形。(3)能通过孔径0.8μm的除菌滤器。(4)在高渗平板上形成丝状或颗粒状菌落。(5)透射电镜检查,可见细胞壁有不同程度的缺损。  相似文献   
54.
慢性体外反搏对高胆固醇血症猪动脉内皮细胞的影响   总被引:7,自引:0,他引:7  
目的 探讨慢性增强型体外反博(EECP)能否在体修复高胆同醇血症引起的猪动脉内皮细胞(ECs)损伤。方法 高胆固醇血症猪反搏36h后,取前降支进行扫捕电镜检查,收集胸主动脉ECs进行蛋白质组学检查。结果 高脂组冠脉ECs排列不规则、大量脱落、斑块形成,反搏组ECs呈流线型排列、脱落程度显著减轻:与高脂组相比,在反搏组的ECs检测到6种高表达的蛋白。结论 慢性EECP可能通过调节ECs蛋白表达,改善ECs粘附性和代谢及减轻ECs内皮凋亡,从而修复高胆固醇血症对动脉内皮形态和功能的损伤:  相似文献   
55.
Physiological and anatomical characteristics of antennal lobe interneurons in female Spodoptera littoralis (Boisd.) were investigated using intracellular recording and staining techniques. Responses of local interneurons and projection neurons to female sex pheromone components, host plant odours, and behaviourally active oviposition deterrents were recorded. We found local interneurons and projection neurons that responded specifically to only one or two of the tested odours, but we also found less specific cells, and neurons that responded to most of the tested odourants. These findings show that there are not only specific olfactory pathways in female moths up to the protocerebral level, but also that integration can begin in the antennal lobe. No correlation was found between the degree of specificity of either local interneurons or projection neurons and their respective morphological characteristics. Specialized and unspecialized local interneurons arborized throughout the antennal lobe. Specialized and unspecialized projection neurons had uniglomerular arborizations in the antennal lobe and sent their axons to the calyces of the mushroom body, and to the lateral horn of the protocerebrum. One specific projection neuron had multiglomerular arborizations and projected only to the lateral horn of the protocerebrum. Projection neurons arborizing in the glomeruli closest to the entrance of the antennal nerve always responded to pheromone components. No other correlations were found between the arborization pattern of projection neurons in the antennal lobe or in the protocerebrum and their response characteristics. The sensitivity of local interneurons and projection neurons was in the same range as that of receptor neurons in olfactory sensilla on the antennae, suggesting a much lower convergence in the central nervous system in females than in the pheromone-processing pathway in males. © 1994 Wiley-Liss, Inc.  相似文献   
56.
目的:观察交感神经节在体外培养中的生长和形态学特点。方法:无菌,取新生大鼠椎旁交感神经节,用Maximow培养法在相差显微镜下动态观察7天。终止2后,用Holmes还原银染色法显示神经纤维。结果:交感神经节在壁后12-18h开始生长,24-48h由交感神经节长出的纤维长约0.5mm,72-96h可见神经纤维伸长到1-2mm以上,并呈放射状向四周延伸。Holmes还原银染色的标本中可见大量银染的神经  相似文献   
57.
To investigate whether body morphology, obesity and its long time evolution were associated with lumbar and femoral bone mineral density (BMD) in premenopausal women of the same age. Design: Cross-sectional study. Subjects: 72 healthy premenopausal women born in 1950 (42 years) with a regular physical activity. Measurements: BMD measured by dual-X-ray absorptiometry (DEXA) at lumbar spine and proximal femur; body weight, body mass index (BMI), BMI at 20 years (BMI-20), increase in BMI since age of 20 (BMI->20), body circumferences (breast, waist, hip) and their ratios (WHR, BHR, WBR), smoking and alcohol intake. Results: Lumbar spine BMD did not correlate with any anthropometric measurement. Femoral BMDs correlated positively with weight, BMI, BMI-20, breast, waist, WHR and BHR. The BMI-20 explained the 5% and the current BMI the 13% of variance of total femur BMD. After adjustment for weight or BMI, breast circumference and BHR remained significantly correlated with all femoral BMDs sites except neck. Weight was the best predictor for neck BMD (R2 = 0.08; p < 0.02), and BHR for Ward's triangle (R2 = 0.12; p < 0.01) and trochanter (R2 = 0.10; p < 0.001). Alcohol intake, cigarette smoking, and age of menarche were not related to BMDs. Conclusion: In premenopausal women of the same age, lumbar spine BMD was not associated with any anthropometric measurement. Greater BHR and its long time of evolution may be determinants of greater femoral BMD (trabecular), whereas body weight may be determinant of femoral neck BMD (cortical). Further studies are needed to determine whether large breast to hip ratio may be considered as a protective factor for femoral osteoporosis.  相似文献   
58.
Objective : To measure the geometric resistance to blood flow in human colorectal carcinoma. Although tumor blood flow is of central importance in both the detection and the treatment of cancer, the determinants of blood flow through the neoplastic circulation are poorly understood. Methods : Human colorectal carcinomas (tissue weight = 272 g ± 43 g (SD), n = 6) were perfused ex vivo with a buffered physiological salt solution of known viscosity at flow rates ranging from 2.5 to 40 ml/min and perfusion pressures from 8 to 100 mm Hg. The geometric resistance was determined from the slope of the pressure-flow curve. For examination of the principal determinant of geometric resistance, the vascular architecture, one of the tumors was perfused with Batson's No. 17 polymer and macerated in KOH to produce a positive vascular cast that was used for measurement of vascular branching patterns and dimensions. Results : The pressure-flow relationship was linear at perfusion pressures above 40 mm Hg, and the geometric resistance, z0, was constant at approximately 6.5 ± 109g/cm3. Below 40 mm Hg, z0 increased rapidly. The architecture of the arteriolar and capillary networks of human colorectal carcinoma is similar to those of experimental rodent tumors. Capillaries in planar and nonplanar mesh-works had mean segment diameters of 11 ± 2 and 9.6 ± 2 μm, lengths of 46 ± 24 and 107 ± 40 μm, and intercapillary distances of 46 ± 13 and 74 ± 24 μm, respectively. Conclusions : The geometric flow resistance in neoplastic tissue is 1–2 orders of magnitude higher than that observed in normal tissues. A decrease in functional vascular cross-sectional area may explain the additional increase in resistance at small perfusion pressures. The observed flow resistance may be due to the specialized arteriolar and capillary network architecture, pressures exerted by proliferating cancer cells, and/or coupling between vascular and extravascular flow. These observations demonstrate that tumor vascularity alone may not be indicative of flow resistance or tumor susceptibility to blood-borne therapeutic agents.  相似文献   
59.
Background The purpose of this study was to explore neuroretinal transplantation in a large animal model of severe retinitis pigmentosa and to establish graft development, long-term survival, graft-host integration, and effects on the host retina. Methods Rhodopsin transgenic pigs, aged 6 months, received in one eye a fetal full-thickness neuroretinal sheet in the subretinal space by means of vitrectomy and retinotomy. Six months postoperatively, eyes were studied in the light microscope and with immunohistochemical markers. Full-field electroretinography (ERG) was performed at 4 and 6 months. Results Laminated grafts with well-organized photoreceptors, rod bipolar cells, and Müller cells were found in five of six eyes. Neuronal connections between graft and host retina were not seen. In the five eyes containing a graft, the number of surviving rods in the host retina was significantly higher compared with unoperated eyes. The ERG did not reveal any significant difference in b-wave amplitude between operated and control eyes, but the cone-derived response in operated eyes increased significantly from 4 to 6 months while the rod response in control eyes decreased significantly. Conclusions Fetal full-thickness neuroretina can be transplanted safely to an eye with severe retinal degeneration. In their major part, the transplants develop a normal laminated morphology and survive for at least 6 months. Graft and host retinal neurons do not form connections. Retinal function in the host is reduced initially by the surgical trauma, but the presence of a well-laminated graft counteracts this effect and rescues rods from degeneration. Supported by The Foundation Fighting Blindness (grant# C-NC02-798-0078), The Faculty of Medicine, University of Lund, The Swedish Research Council, The Princess Margaretas Foundation for Blind Children, The 2nd ONCE International Award for New Technologies for the Blind.  相似文献   
60.
用复方泛影葡胺注射液对1,020例不孕症者作子宫输卵管造影。结果:子宫腔形态异常540例。双侧输卵管通畅但形态异常者268例。单侧输卵管通畅但形态异常者110例。结果表明:子宫输卵管形态异常与不孕有密切关系。  相似文献   
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