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41.
目的通过化学方法制成动物核性白内障模型,探讨相对能量复合指数(RECP)与角膜内皮细胞活性的关系。方法将5种化学物质注入晶状体,以透过黑白条纹的清晰程度判断晶状体混浊程度并分级。然后将实验眼球分为6组(Ⅰ组为对照组;Ⅱ-Ⅵ为实验组),行标准超声乳化白内障摘除手术。手术后立即取下角膜,作锥蓝-茜素红联合染色标本和扫描电镜标本。结果晶状体内注入甲醛、冰醋酸、无水乙醇、丙酮和苯扎溴铵均能形成晶状体混浊,其中:冰醋酸致晶状体混浊能力最弱,无水乙醇、丙酮次之,甲醛、苯扎溴铵最强。当RECP≤90时,锥蓝-茜素红双重染色和扫描电镜均表明角膜内皮细胞活性好,其形态和细胞联接均无改变。当RECP=120时,角膜内皮细胞形态尚正常,但是细胞联结和胞膜部分破坏。当RECP=150时,角膜内皮细胞严重损伤。结论用化学方法制作核性白内障模型供过渡训练使用是可行的。当RECP超过某一数值(>90)时,即与角膜内皮细胞的活性成负相关。  相似文献   
42.
At the Indiana University Medical Center, 99 patients with medically intractable complex partial seizures (MI-CPS) had presurgical evaluation with subsequent anterior temporal lobectomy. The majority of the patients had single photon emission tomography (SPECT) performed interictally as well as during an actual epileptic seizure (ictal scan). Decreased regional cerebral perfusion (rCP) was seen in 54/94 (57%) of the interictal scans corresponding to the eventual site of the surgery. However, ictal scans provided a higher yield; increased rCP in the temporal lobe during an actual seizure was observed in 60/82 (73%) concordant to the side of surgery. SPECT is a useful, noninvasive method of localizing the epilepti-form focus in patients with MI-CPS considered for resective surgery. Both interictal and ictal SPECT need to be performed; combined interictal hypo-perfusion and ictal hyperperfusion in the same focal area are unique to epileptogenic lesions. Ictal SPECT studies can be performed in the majority of patients during the period of continuous video/EEG monitoring with only a little additional effort. Combining the results of functional brain imaging (interictal and ictal SPECT, PET) with clinical semiology of seizures, surface and sphenoidal EEG, magnetic resonance imaging and other non-invasive tests, anterior temporal lobectomy can be recommended in approximately two-thirds of the patients without resorting to potentially dangerous intracranial EEG monitoring.  相似文献   
43.
本文用反复静脉注射小剂量牛血清白蛋白复制家兔慢性肾炎,用羊踯躅根治疗。同时,用该药对慢性肾炎病人进行疗效观察。阳性组兔肾小球呈现中至重度颗粒形免疫荧光,肾组织呈明显慢性硬化性肾小球肾炎改变。尿蛋白±~++。治疗组兔及病人治疗后病变及症状均明显减轻或消失。结果提示循环免疫复合物反复沉着可引起兔类似人类的慢性硬化性肾小球肾炎,羊踯躅根对病变有一定的控制和治疗作用,这可能与其抑制免疫发病机制有关。  相似文献   
44.
HLA-DR expression on circulating monocytes varies as a function of disease activity in patients with multiple sclerosis (MS), a putative immunopathological demyelinating disorder. Specifically, monocytes isolated from subjects with active MS exhibit reduced HLA-DR antigen density, and immunoregulatory aberrations such as impaired T lymphocyte-mediated suppression correlate strongly with this quantitative defect. To address the mechanism underlying this phenomenon, we compared in vitro regulation of HLA-DR by interferon beta (IFN beta), interferon gamma (IFN gamma), and lipopolysaccharide (LPS) in monocytes from patients with stable and active MS and normal individuals. Interferon-gamma and LPS enhanced monocyte expression of HLA-DR equally in both MS patient groups, suggesting that underexpression of HLA-DR in active MS was not explained by impaired in vivo monocyte responsiveness. Furthermore, interferon regulation of HLA-DR in normals and stable MS subjects was indistinguishable, indicating that aberrant interferon-mediated regulation of class II major histocompatibility complex (MHC) on circulating monocytes does not appear to be a characteristic of the MS disease state.  相似文献   
45.
The distribution of GABA-producing neurons in the brainstem auditory nuclei of the rat was investigated immunohistochemically by using an antibody to glutamic acid decarboxylase (GAD). In the cochlear nuclei, GAD immunoreactive neurons are present only in the superficial granular and molecular layers, whereas terminals are found in all subdivisions of the nuclei and are particularly dense surrounding large spherical cells and one type of stellate cell. In the superior olivary complex, GAD immunoreactive neurons are located in the lateral olivary nucleus and throughout the periolivary region. Immunoreactive terminals are distributed along dendrites of principal cells of the medial and lateral olivary nuclei and are clustered around somata of globular neurons of the nucleus of the trapezoid body. An extremely dense band of immunoreactive somata and terminals is present along the ventral edge of the olivary complex. The ventral, intermediate, and dorsal nuclei of the lateral lemniscus contain small fusiform GAD-immunoreactive neurons and a moderately dense plexus of immunoreactive terminals. The inferior colliculus contains a large population of GAD-immunoreactive perikarya and an extremely dense accumulation of immunoreactive terminals in the central, dorsomedial, and external nuclei. These observations indicate that GABA systems are involved in function at all levels of the brainstem auditory pathway.  相似文献   
46.
目的探讨结节性硬化症多器官损害的临床特点以提高诊断治疗水平。方法回顾性分析7例结节性硬化症伴皮肤、大脑、肾脏、肝脏等多器官损害患者的临床资料,探讨其特征性临床表现及影像学改变。结果7例患者均有多器官损害,累及两个器官3例,3个及以上器官损害4例;皮肤损害主要为面部血管纤维瘤6例,皮肤色素脱失斑7例,鲨鱼皮斑3例,趾甲下纤维瘤1例;癫痫发作6例,智力低下4例,颅脑CT或MRI检查提示室管膜下结节4例,皮质结节2例;4例合并双侧肾脏多发错构瘤,1例合并肝脏错构瘤。结论特殊的皮肤损害、癫痫发作、智力低下,脑CT或MRI检查提示室管膜下结节或皮质结节或内脏多发性错构瘤为本病的主要临床特征,提高本病的认识有助于早期诊断和治疗。  相似文献   
47.
Electrocatalytic dehalogenation of organohalides was studied using a nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode. The nickel(II) tetraazamacrocyclic complex-modified graphite felt electrode was prepared by attaching nickel(II) (6-(2′-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)perchlorate chemically to the carboxyl groups of a thin poly(acrylic acid) layer coated on the graphite felt. The modified electrode gave a reversible electron transfer for the nickel(II)/nickel(I) redox couple in cyclic voltammetry at ?0.95 V versus Ag/AgCl. A preparative electrocatalytic dehalogenation of organohalides was successfully achieved on the modified electrode with an adequate current efficiency (55.6–94.8%), conversion (34.2–100%) and turnover number of the Ni catalyst (667–3333).  相似文献   
48.
目的观察高迁移率族蛋白B1(HMGB1)对树突状细胞(dendritic cells,DC)表面共刺激分子表达的影响,并对其机制进行初步探讨。方法分离正常Wistar大鼠脾脏DC后置于96孔培养板(1×10~5/孔),采用HMGB1刺激,观察HMGB1刺激与DC表面共刺激分子CD80、CD86和主要组织相容性复合物(MHC)Ⅱ表达的时间-效应关系及剂量-效应关系。结果HMGB1刺激后,DC表面共刺激分子CD80、CD86和MHCⅡ表达分别于24~72 h明显上调(P<0.05,0.01),其中以作用48 h后DC表面共刺激分子表达上调尤为显著(P<0.01);0.1μg/ml、1μg/ml、10μg/ml的HMGB1刺激均可诱导DC表面共刺激分子CD80、CD86和MHCⅡ表达增强(P<0.05,0.01),其中HMGB1的浓度在1μg/ml时,大鼠DC表面共刺激分子CD80、CD86和MHCⅡ的表达增强最明显(P<0.01)。结论HMGB1能诱导DC表面共刺激分子表达增强,HMGB1可能是诱导DC成熟的免疫刺激信号。  相似文献   
49.
用McAb和ABC法测定了38例慢性再生障碍性贫血(CAA)患者外周血T淋巴细胞亚群(简称T亚群)。与健康人相比,CAA的Ts明显增高(P<0.001),Th/T5明显降低(P<0.001)。并发现外周血Hb水平、病程、疗效及中医证型与T亚群相关。按气血两虚肾阳虚、肾阴虚、肾阴阳两虚的顺序,患者Th逐渐降低,Ts逐渐升高,Th/Ts明显降低。后两组比前两组Th/Ts下降更显著(P<0.01),提示阳损及阴时机体免疫机能发生更大的改变,从T亚群水平揭示了中医证型特别是肾阳虚、肾阴虚的内涵。  相似文献   
50.
The subcellular localization of the inositol 1,4,5-trisphosphate receptor protein, P400, was studied in the vestibular complex, an area to which Purkinje cells project, as well as in neurons of the dorsal cochlear nucleus and in ectopic Purkinje cells of adult rat brain. The receptor was demonstrated by electron microscopical immunocytochemistry using the avidin-biotin peroxidase complex procedure, with the monoclonal antibody 4C11 raised against mouse cerebellar inositol 1,4,5-trisphosphate receptor protein. Immunoreactivity was found in preterminal fibres and terminal boutons in the nuclei of the vestibular complex, generally associated with the subsurface systems and stacks or fragments of smooth endoplasmic reticulum. Ectopic Purkinje cells and cartwheel cells of the dorsal cochlear nucleus also displayed immunoreactivity, but this was much less intense in the latter. The results of the present study suggest that this receptor protein, involved in the release of Ca2+, is located in sites that enable it to influence the synthesis, transport and release of neurotransmitters.  相似文献   
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