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991.
应用超声生物显微镜检查原发性婴幼儿型青光眼的眼前节形态特征 总被引:4,自引:1,他引:3
目的 了解原发性婴幼儿型青光眼在活体状态下的眼前节组织结构特点。方法 应用超声生物显微镜,以50mHZ的超高频超声探关,对38例(58只眼)原发性婴幼儿型青光眼的眼前节结构进行测量和动态学检查。结果 PIG患儿无论发病早晚、病情轻呈年龄大小,其最主要的病变特征是巩膜突与留心 角顶点的相对位置发生变化,3/4患眼的巩膜突位于房角顶点外侧或后外方,1/4患眼的巩膜突虹膜根部附着处平行,眼状突长度和厚度 相似文献
992.
为探讨初始强化免疫对控制和消除麻疹的效果,1998 年6 ~7 月份对韶关市所有6 月龄至15 岁人群实施MV 初始强化免疫后进行血清学检测和流行病学观察。结果强免后麻疹总抗体阳性率从90-8 % 升至99-5 % ,GMRT 从861-8 增长到4660-2 ,低抗体率从31-0 降至1-8 % ,免疫成功率高达98-9 % ;强免后(1998 年7 ~12 月、1999 年1 ~5 月) 麻疹发病报告分别为27 例和1 例,比强免前(1998 年1 ~6 月252 例) 大幅度下降。说明MV 初始强化免疫控制麻疹效果显著,是控制和消除麻疹的可取策略。 相似文献
993.
利用独立准直器开展调强放疗算法研究 总被引:2,自引:0,他引:2
戴建荣 《中国医疗器械杂志》1999,23(6):316-320,333
研究利用独立准直器调整射野强度分布。设计了两种递推的办法来计算射野处序列,采用模拟退火算法优化射野片的照射顺序。并以在Varian 600C轲速器上实施三个临床调强射野为例,估计IC调强放疗的照射时间。照射时间一般在5至10min。它近似与机器剂量率成反比,并受调强算法,矩阵元素大小以及强度分级数的影响。 相似文献
994.
准分子激光原位角膜磨削术后继发圆锥角膜病因分析 总被引:1,自引:0,他引:1
目的 对4眼准分子激光原位角膜磨削术(LASIK)后继发圆锥角膜进行病因分析。方法 为4眼重度近视患者行常规LASIK治疗,术后角膜地形图分析确诊圆锥角膜,对手术前皇检查的各项数值行回顾性分析。结果 4眼LASIK术后患者激光切削后剩余角膜基质厚度均大于200um,眼压正常,术后7个月~1年半发生圆锥角膜,其中1眼行穿透性角膜移植术获得满意疗效。结论 虽然LASIK术后保留角膜常规厚度,眼压正常, 相似文献
995.
We investigated the synaptic connectivity of two populations of recoverin-labeled bipolar cells and GABAergic neurons in the inner plexiform layer (IPL) of the rat retina. Two types of cone bipolar cells, type 2 and type 8, were stained with anti-recoverin antibodies, and GABAergic neurons were stained with anti-glutamic acid decarboxylase (GAD) antibodies. Type 2 cone bipolar axons received synaptic input from amacrine cell processes in 177 cases; among these amacrine cell processes, 92 processes (52.0%) were GAD-like immunoreactive. A total of 159 amacrine cell processes, which are presynaptic to type 8 cone bipolar cells, were observed. Among these processes, 117 processes (73.6%) were GAD-like immunoreactive. The postsynaptic elements at the ribbon synapses of recoverin-labeled cone bipolar cells were observed in 482 processes. In both type 2 and type 8 cone bipolar cells, the major output was to amacrine cell processes. At the ribbon synapses of the type 2 cone bipolar cells, 224 of the postsynaptic profiles were amacrine cell processes, 97 processes (43.3%) were GAD-like immunoreactive. In type 8 cone bipolar cells, 45 processes (30.2%) of 149 amacrine cell processes were GAD-like immunoreactive. Our results provide morphological evidence that GABA is a major transmitter involved in the visual processing of type 2 and 8 cone bipolar cells and GABA may have a stronger influence on type 8 cone bipolar cells than type 2 cone bipolar cells in the IPL of the rat retina. 相似文献
996.
PURPOSE: To investigate the effect of mitomycin C (MMC) after long-term storage on proliferation of human Tenon's fibroblasts in vitro. METHODS: Human Tenon's fibroblasts in tissue culture were exposed for 5 minutes to MMC (0.4 mg/mL) that was either freshly prepared or had been stored for as long as 18 months at either 4 degrees C or -20 degrees C. The MTT colorimetric assay was used to determine the inhibition of proliferation as measured indirectly by mitochondrial activity. RESULTS: The inhibition rate was 88% using fresh MMC, and declined to a mean of 73% when using MMC that had been stored for as long as 18 months at 4 degrees C; this decrease was not statistically significant. The mean inhibition for MMC stored at -20 degrees C was 68%, and this was significantly less than inhibition with fresh MMC. Inhibition did not vary significantly with MMC after different storage times. CONCLUSION: Mitomycin C continues to have strong in vitro antiproliferative effects when stored for as long as 18 months at 4 degrees C or -20 degrees C. A significant decline in potency compared with fresh MMC occurs when MMC is stored at -20 degrees C. 相似文献
997.
Immunohistological localisation of vascular endothelial growth factor in human endometrium. 总被引:2,自引:0,他引:2
B Naresh J Sengupta V Bhargava G Kinra J Hu D Ghosh 《Indian journal of physiology and pharmacology》1999,43(2):165-170
Several polypeptide growth factors regulate epithelial and stromal development in endometrium under the influence of estrogen and progesterone, and thereby regulate growth and differentiation of endometrium during menstrual cycle. However, little is known about the angiogenic growth factors that may affect endometrial vasculature throughout each menstrual cycle. Vascular endothelial growth factor (VEGF) is suggestively an important angiogenic growth factor in the female reproductive tract. The aim of the present study was to immunolocalize and assess semi-quantitatively VEGF immunostaining in cells of proliferative phase (n = 3), secretory phase (n = 6) and hyperplastic (n = 6) human endometrial samples. VEGF concentrations were significantly higher in glandular (P < 0.001) and stromal (P < 0.01) compartments of proliferative stage endometrium compared with those in secretory stage and hyperplastic endometrial samples, with no difference in the scores for glandular and stromal compartments between secretory stage and hyperplastic endometrial samples. Generally, glandular expression of VEGF was higher as compared to stromal compartment. Thus, it appears that endometrial VEGF expression and concentration are enhanced by estrogen, and may be correlated with neovascularization and increased vascular permeability during late proliferative period. Additionally, there was no enhancement in VEGF expression in hyperplastic glands, suggesting that regulation of glandular growth and that of angiogenesis in human endometrium operate through different mechanisms. 相似文献
998.
Antagonism of paraoxon intoxication by recombinant phosphotriesterase encapsulated within sterically stabilized liposomes 总被引:4,自引:0,他引:4
Petrikovics I Hong K Omburo G Hu QZ Pei L McGuinn WD Sylvester D Tamulinas C Papahadjopoulos D Jaszberenyi JC Way JL 《Toxicology and applied pharmacology》1999,156(1):56-63
This investigation effort is focused on increasing organophosphate (OP) degradation by phosphotriesterase to antagonize OP intoxication. For these studies, sterically stabilized liposomes encapsulating recombinant phosphotriesterase were employed. This enzyme was obtained from Flavobacterium sp. and was expressed in Escherichia coli. It has a broad substrate specificity, which includes parathion, paraoxon, soman, sarin, diisopropylfluorophosphate, and other organophosphorous compounds. Paraoxon is rapidly hydrolyzed by phosphotriesterase to the less toxic 4-nitrophenol and diethylphosphate. This enzyme was isolated and purified over 1600-fold and subsequently encapsulated within sterically stabilized liposomes (SL). The properties of this encapsulated phosphotriesterase were investigated. When these liposomes containing phosphotriesterase were incubated with paraoxon, it readily degraded the paraoxon. Hydrolysis of paraoxon did not occur when these sterically stabilized liposomes contained no phosphotriesterase. These sterically stabilized liposomes (SL) containing phosphotriesterases (SL)* were employed as a carrier model to antagonize the toxic effects of paraoxon by hydrolyzing it to the less toxic 4-nitrophenol and diethylphosphate. This enzyme-SL complex (SL)* was administered intravenously to mice either alone or in combination with pralidoxime (2-PAM) and/or atropine intraperitoneally. These results indicate that this carrier model system provides a striking enhanced protective effects against the lethal effects of paraoxon. Moreover when these carrier liposomes were administered with 2-PAM and/or atropine, a dramatic enhanced protection was observed. 相似文献
999.
四氢巴马汀同类物对福尔马林致痛诱导Fos蛋白表达的影响 总被引:1,自引:0,他引:1
目的 研究四氢巴马汀(THP)同类物对福尔马林致痛诱导的Fos蛋白表达的影响,以阐明THP同类物的镇痛机制。方法 在右后肢脚掌皮下注射5%福尔马林50μL,诱发性疼痛,用免疫组织化学方法观察Fos的蛋白表达,结果:腹腔注射THP同类物和D2受体拮抗剂螺哌隆诱导的Fos蛋白表达主要位于纹状体和伏膈核,D2受体激动剂喹吡罗可阻滞l-THP和螺哌隆诱导的Fos蛋白表达,THP同类物明显增加脑干下行痛觉调 相似文献
1000.
RP—HPLC法对不同产地蝙蝠葛几种主要生物碱的测定 总被引:13,自引:0,他引:13
目的:研究不同产地蝙蝠葛几种主要生物碱在质与量上的区别。方法:采用有机溶剂提取生药,应用RP-HPLC方法在东北产和咸宁产蝙蝠葛根茎中几种主要脂溶性生物碱定性定量测定。结果:东北生一最高的生物碱前3位依次是蝙蝠葛苏林碱、蝙蝠碱和guattegaunerine;而咸宁药材则为蝙蝠葛碱、蝙蝠葛诺林碱及蝙蝠葛新诺林碱,不含蝙蝠葛苏林碱。结论:不同产地蝙蝠葛药材所含生物碱在质和量两方面均有显著差异。 相似文献