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101.
W Mao  L Zeng  Q Ma  Y Chen  Z Dai  P Tang  X Guo  D Li  W Su 《眼科学报》1990,6(3-4):88-90
We report here the preliminary effects of zinc iontophoresis in treatment of 26 Rp patients who had decreased zinc serum level or abnormal ratio of serum copper to zinc. Through more than 20 to 30 times of therapy, the vision of 15.38% eyes increased more than "3 lines", 4% eyes increased more than 5 degrees in the visual field, 13.46% eyes improved in dark adaptation threshold (greater than 1.0), the visual functions of the rest eyes were slightly improved or unimproved. The fundus didn't change before & after treatment. There were no changes of ERG in 8 eyes of 4 cases. In addition, the advantages and disadvantages between Zn iontophoresis and Zn compound taken orally, the improvement of vision by direct electric current therapy, the relationship between the metabolism of Zn element and Vit A and influence of Zn over the mechanism of dark adaptation were also briefly discussed.  相似文献   
102.
石蜡切片中BCL-6抗原失活机制及修复   总被引:1,自引:1,他引:0  
张永清  黄高昇  赵一岭  王哲  闫庆国  郭英 《医学争鸣》2001,22(15):1352-1354
目的 探讨石蜡切片中BCL 6抗原失活机制及修复的最佳方法 .方法 淋巴组织反应性增生 11例石蜡切片分别用二乙胺四乙酸 (EDTA)、柠檬酸、碳酸钠及去离子水 4种与钙离子结合力不同的修复液 ,结合高压、微波和煮沸 3种不同方法修复后 ,比较检出的BCL 6阳性率及强度 .结果 BCL 6阳性率由高至低依次为 :EDTA 0 .73>柠檬酸 0 .45 (P<0 .0 1) >碳酸钠 0 .12 (P <0 .0 1) ,去离子水组无 1例阳性 .高压修复阳性率 0 .5 5 >微波修复 0 .2 8和煮沸修复 0 .12 (P <0 .0 5 ) .不同修复液与高压结合修复检出BCL 6阳性率及强度 :EDTA与柠檬酸阳性率分别为 1,0 .82 (P >0 .0 5 ) ,高于碳酸钠组 (0 .36 )和去离子水组 (0 ) (P <0 .0 1) .EDTA组强阳性占 0 .82 ,显著高于其他各组 (P <0 .0 1) .结论 EDTA结合高压是修复BCL 6抗原的理想方法 ,钙离子的参与可能是甲醛固定后BCL 6抗原失活的原因之一  相似文献   
103.
庆大霉素前庭损害报警耳聋的实验研究   总被引:1,自引:0,他引:1  
目的观察庆大霉素对前庭及耳蜗的损害。方法对肌肉注射庆大霉素(250mg·kg-1/d)连续3天和7天的两组豚鼠进行前庭和耳蜗功能与形态的观察。结果发现用药3天仅影响前庭,而用药7天则前庭和耳蜗均受损害,提示庆大霉素早期损害前庭的特点可以报警耳蜗的损害。结论因此,在应用庆大霉素过程中,发现前庭功能改变时,如能及时停药,可以避免耳聋的发生。  相似文献   
104.
目的 :研究孕激素受体拮抗剂米索前列醇对妊娠晚期引产的效果。方法 :采用双盲对照法 ,选择晚期妊娠无米索前列醇禁忌证 6 0例为研究组 ,采用阴道给药总量 1 0 0mg ;另选择有关参数相同的 6 0例 ,应用催产素 ,两组观察相关指标体系进行比较。结果 :引产效果 ,分娩时间 ,宫颈评分等指标研究组均优于对照组。结论 :米索前列醇用于晚期妊娠引产效果优 ,安全  相似文献   
105.
The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.  相似文献   
106.
探讨药物致肾损伤早期诊断方法。用酶法测定碱性磷酸酶(ALP)。速率法测γ-谷氨酰转肽酶(GGT),N-乙酰-β-D氨基葡萄糖苷酶(NAG)、β-半乳糖苷酶(Gal)及肌肝(UCr),磺柳酸法测尿蛋白(Pro)。结果:尿酶升高均早于尿蛋白的出现,特别是NAG于用药后第3天即有显著升高,Gal则在用药后3d内持续升高,尿酶,特别是NAG是药物引起肾损伤早期诊断指标。  相似文献   
107.
目的:综述P^27的研究进展。方法:光盘检索有关献,归纳综合整理。结果:P^27是细胞周期的相关蛋白,P^27白过度表达可抑制细胞周期的进程,阻断细胞生长于G1期。结论:P^27是细胞周期中重要的负性调控控因子,是一种新的侯选的肿瘤抑制基因。  相似文献   
108.
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields.  相似文献   
109.
Purification of thrombospondin from human platelets   总被引:1,自引:0,他引:1  
Summary Thrombospondins are a rapidly growing family of adhesive proteins that have diverse activities to modulate cellular growth, motility, and gene expression. Thrombospondin-1 (TSP) was the first identified member of this family and is the major form of thrombospondin in human platelets. A method is described to prepare TSP from human platelets in biologically active form with minimal degradation or contamination with other platelet proteins.  相似文献   
110.
The push-pull technique was used to investigate the release of the excitatory amino acid glutamate in the posterior hypothalamic area of the conscious rat. The hypothalamus was superfused through the pushpull cannula with artificial cerebrospinal fluid (CSF), and the superfusate was collected in time periods of 10 min when ionic conditions in the CSF were changed, or in short periods of 3 min when blood pressure changes were evoked. The mean glutamate release rate was 2.8 + 0.7 pmol/min. Depolarization by hypothalamic superfusion with CSF containing 50 mM K+ enhanced the release of glutamate in the presence of Ca2+. The K+-induced release was attenuated by 40% when the hypothalamus was superfused with Ca2+-free CSF. Replacement of Ca2+ by Mg2+ abolished the K+-induced release of glutamate. Hypovolaemia elicited by haemorrhage enhanced the release rate of glutamate. Similarly, a hypotension elicited by i.v. injection of chlorisondamine (3 mg/kg) led to a pronounced and permanent enhancement in glutamate release. The effects of hypovolaemia and chlorisondamine on glutamate release were abolished in aortic denervated rats, indicating that this response is due to a decrease of impulse generation in baroreceptors. A hypovolaemia elicited by blood infusion did not affect the release of glutamate. Similarly, a pronounced pressor response to phenylephrine (15 /kg per minute) infused intravenously for 9 min was ineffective.The results show that the K+-induced release of glutamate in the hypothalamus is dependent on the presence of Ca2+. The increase in glutamate release rate by hypovolaemia or chlorisondamine suggests that the glutamatergic neurons in the posterior hypothalamic area respond to unloading of aortic baroreceptors and possess a counteracting, hypertensive function.  相似文献   
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