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81.
Summary We present a case of blindness and Anton’s syndrome in a psychiatric patient with late diagnosis of a giant frontal meningioma. The criteria for advanced diagnostic imaging in the psychiatric population are discussed. We conclude that MR or CT scan is indicated in psychiatric in-patients who fail to improve with standard psychiatric treatment. This strategy should be submitted to a cost-benefit analysis.  相似文献   
82.
Chronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to lead to the development of hepatotoxicity and carcinogenicity in the liver of female rats. In this study, we investigated hepatic gene downregulation in response to acute and subchronic TCDD exposure. We identified 61 probes which exhibited a downregulation of twofold or greater following subchronic (13 weeks) exposure to TCDD. Comparative analysis of the hepatic expression of these 61 probes was conducted with rats subchronically exposed to PeCDF, PCB126, PCB153, and a mixture of PCB126 and PCB153. PCB153 produced little or no alteration in these probes, while the binary mixture mimicked most closely the downregulation observed with TCDD. To discern if the repression of genes within this probe set occur as a primary response to TCDD exposure, we analyzed the early responsiveness of 11 genes at 6, 24, and 72 h following a single exposure to TCDD. We observed early repression of the 11 genes within this early time course, indicating that the repression of this subset of genes occurs as a primary response to TCDD exposure and not as a secondary response to 13 weeks of subchronic treatment. In addition, the gender, species, and AhR dependence of these responses were also investigated. Gender- and species-dependent repression was observed within this subset of genes. Furthermore, utilizing AhR knockout mice, we were able to determine the AhR-dependent downregulation of seven of 11 genes. Together these results assist efforts to understand the multitude of effects imposed by TCDD and AhR ligands on gene expression.  相似文献   
83.
首先将薯蓣皂苷通过3-羟基位的改造,制成3-琥珀酰薯蓣皂苷,再通过碳二亚胺将其与牛血清白蛋白和卵清蛋白偶联制成免疫原和包被原,免疫新西兰大白兔制备出多克隆抗体,抗体效价为1:12800,为进一步建立黄精皂苷ELISA方法打下基础。  相似文献   
84.
Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.  相似文献   
85.
The incidence of wound botulism is increasing and the epidemiology of the disease is changing. The majority of new cases are associated with injection drug use, in particular, the use of Mexican black tar heroin. This case report and discussion of wound botulism illustrate the following important points: Dysphagia, dysphonia, diplopia, and descending paralysis, in association with injection drug use, should alert the treating physician to the possibility of wound botulism. In such patients, the onset of respiratory failure may be sudden and without clinically obvious signs of respiratory weakness. For the reported patient, maximum inspiratory force measurements were the only reliable indicator of respiratory muscle weakness. This is a measurement not routinely performed in the ED, but may prove essential for patients with suspected wound botulism. To minimize the effect of the botulinum toxin and to decrease length of hospital stay, antitoxin administration and surgical wound debridement should be performed early.  相似文献   
86.
人参根总皂甙对热应激小鼠免疫功能保护作用的机制初探   总被引:1,自引:0,他引:1  
小鼠在45℃高温环境15 min.末梢血T淋巴细胞百分数和淋巴细胞占白细胞百分数均下降.血清皮质酮升高。应激前15 min lP人参根总皂甙(GRS)50、100 mg·kg~(-1)可防止末梢血T淋巴细胞百分数的降低,但不能抑制血清皮质酮的升高。GRS50mg·kg~(-1)ip可防止末梢血中淋巴细胞占白细胞百分数的降低。GRS50 mg·kg~(-1)、利血平0.5 mg·kg~(-1)或水杨酸毒扁豆碱0.3 mg·kg~(-1)ip均可消除热应激对小鼠迟发超敏反应的抑制作用。  相似文献   
87.
88.
羧乙基锗倍半氧化物对大鼠脑缺血再灌注损伤的保护作用   总被引:7,自引:0,他引:7  
采用结扎双侧颈总动脉后再通的方法复制大鼠脑缺血再灌注损伤模型,通过测定再灌注后大鼠海马组织中脂质过氧化产物丙二醛(MDA),超氧化物歧化酶(SOD)与谷胱甘肽过氧化物酶(GSH—Px)及ATPase的活性,观察了有机锗─羧乙基锗倍半氧化物(CGS)对大鼠脑缺血再灌注后大鼠海马组织中MDA水平,明显保护SOD、GSH─Px、Na+K+─ATPase及Ca2+─AT─Pase活性。表明CGS对大鼠脑缺血再灌注损伤具有保护作用。  相似文献   
89.
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized.  相似文献   
90.
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