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排序方式: 共有500条查询结果,搜索用时 15 毫秒
1.
Olgierd Pucilowski W. Danysz D.H. Overstreet A.H. Rezvani B. Eichelman D.S. Janowsky 《Brain research bulletin》1991,26(4):621-625
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801. 相似文献
2.
作者利用交流电弧和光栅摄谱仪组装了能够绘制谱线轮廓曲线和准确测定谱线宽度的记录仪,用线宽增量法对生物材料(拟血清)中的主要成分Ca和微量元素Cu进行了测定。与黑度法相比,本实验结果的线性好,误差小,再现性有所提高。这些结果表明,用上述仪器装置和线宽增量法进行生物材料含量分析优于黑度法。 相似文献
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Patients with typical left unilateral spatial neglect bisected lines after cueing to the left end-point, the fixation point being monitored with an eye camera. They persisted with the point of initial fixation made after cueing and placed the mark there without searching leftwards again. The rightward shift of fixation to the initial point of fixation thus determined the location of the subjective midpoint. We consider that rightward attentional bias increased the amplitude of this shift that was planned on the basis of the perception of the whole line while cueing. This hypothesis may explain smaller but obvious rightward bisection errors found in the cueing condition. 相似文献
5.
目的探讨下颌骨侧位摄影分别采用一倾斜角度为α的垫板及未采用时,X线中心线倾斜角度各为β、γ之间的关系,为更简捷地拍好下颌骨提供理论参数和实践依据。方法立足于教科书,运用X线摄影原则与数学几何原理进行推理演绎。结果二者之间存在着可替换的关系,即γ=α+β,可以大胆地去除垫板进行直接拍摄。结论不用垫板,只需通过增大X线中心线倾斜角度的方法,同样也能拍摄出一张好照片,且可操作性强,简便易行,实际使用价值更大。 相似文献
6.
Overstreet DH 《Behavior genetics》2002,32(5):335-348
The present review will describe the formation of two pharmacologically selected lines of rats, their behavioral phenotypes, their responses to select drugs, their possible neurochemical correlates, and their use to detect the therapeutic potential of antidepressant drugs. The Flinders Line rats were established at Flinders University in Australia by selectively breeding for differential responses to an anticholinesterase agent from outbred Sprague-Dawley (SD) rats; the Flinders Sensitive Line (FSL) rats were more sensitive to the hypothermic and behavioral suppressing effects of this agent than the Flinders Resistant Line (FRL) rats. The 8-OH-DPAT line rats were established at the University of North Carolina at Chapel Hill by selectively breeding for differential hypothermic responses to the 5-HT1A receptor agonist, 8-OH-DPAT; the high DPAT sensitive (HDS) line rats were more sensitive to the hypothermic effects of 8-OH-DPAT than the low DPAT sensitive (LDS) line rats. Studies of these two pairs of lines have indicated that the FSL and HDS rats are both more susceptible to stress-induced behavioral disturbances. Their usefulness in detecting potential antidepressant drugs and the relationship between mood disorders and drug abuse will be discussed. 相似文献
7.
Parul Jain Urmila Singh Vijay Kumar Rashmi Ratnam Amita Jain 《Indian journal of medical microbiology》2022,40(3):365-369
PurposeCartridge based nucleic acid amplification test (CBNAAT) has been endorsed by the WHO as the screening test for diagnosing extrapulmonary tuberculosis (EPTB). In the present study we report the agreement between CBNAAT (Xpert MTB/RIF), liquid culture (LC) and line probe assay (LPA) for diagnosis of Mycobacterium tuberculosis and detection of drug resistance among EPTB cases.MethodsThe EP samples were subjected to CBNAAT (Xpert MTB/RIF, Cepheid, USA) and wherever possible, to LC (MGIT 960, Becton Dickinson, USA) followed sequentially by first line and second line-LPA (FL-LPA, SL-LPA, Hain Lifescience, Germany) on the isolates.ResultsTotal 566/4080 (13.9%) EP samples were detected positive for M. tuberculosis on CBNAAT. Aspirates from lymph nodes were most often positive (11/30; 36.6%), followed by pus (240/873; 27.5%) and CSF samples (166/104; 15.8%). The detection of M. tuberculosis was more in adults than children except in tissue biopsy samples. Rifampicin resistance was also higher among adults except CSF in which resistance was more in children. Total 185 of 566 (32.7%) CBNAAT positive and 770 of 3510 (21.9%) CBNAAT negative samples could be cultured of which 110/185 (59.4%) and 33/770 (4.3%) respectively turned positive. FL-LPA and SL-LPA of 143 culture isolates showed that 27 isolates had drug resistance, of which 3 (2.1%) were XDR, 11 (7.7%) were Pre-XDR (FQ) and 13 (9.1%) were MDR. Of these 27 resistant isolates, 12 were negative by CBNAAT and two were mislabeled as Rifampicin sensitive or indeterminate based on the unique RpoB gene mutation patterns on LPA. The positive and negative agreements between LC and CBNAAT for detection of M. tuberculosis were 67.1% and 92.7% respectively and between LPA and CBNAAT for rifampicin resistance detection were 98.9% and 92.9% respectively.ConclusionsFor EPTB, CBNAAT should be accompanied with LC wherever possible irrespective of the CBNAAT result. 相似文献
8.
肝癌细胞纤维肌动蛋白的共聚焦激光扫描显微镜光学切片观察 总被引:5,自引:0,他引:5
目的:建立培养细胞共聚焦激光扫描显微镜光学切片的方法。探讨肝癌细胞纤维肌动蛋白(F-actin)的空间结构。方法:采用共聚焦激光扫描显微镜光学切片技术结合异硫酸氢荧光素-鬼笔环肽(FTTC-phalloidin)标记纤维肌动蛋白和碘化丙啶(PI)标记细胞核的荧光探针双重标记技术对肝癌细胞纤维肌动蛋白进行形态学观察和图像分析。结果:肝癌细胞内纤维肌动蛋白微丝形成束状纤维。粗壮而密集,平行排列或纵横交错成网状贯穿整个细胞和细胞突起。结论:(1)共聚焦激光扫描显微镜的光学切片技术结合FTTC-phalloidin和PI荧光探针双重标记技术是观察和分析细胞骨架系统三维立体结构的良好方法;(2)肝癌细胞内纤维肌动蛋白微丝粗壮、形成束状或网状结构。 相似文献
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目的分析病毒性脑炎并发症状性癫痫的风险因素,据此构建列线图预测模型。方法回顾性分析 2018年 2月至 2022年 5月汕头市中心医院收治的 217例病毒性脑炎病人临床资料,抽取 70%为建模集(152例),30%为验证集(65例)。根据病人是否合并症状性癫痫,将建模集进一步分为发生组和未发生组,比较两组病人一般资料,选择差异有统计学意义的指标用逐步向前回归法进行非条件多因素 logistic分析病毒性脑炎病人症状性癫痫发生的影响因素,并采用 R3.4.3软件包绘制基于多因素分析结果的列线图模型。采用 Bootstrap法分别对建模集和验证集进行验证,并绘制受试者操作特征曲线(ROC曲线)和决策曲线(DCA)以评估列线图模型的预测效能和临床净获益率。结果 217例病毒性脑炎病人中,共 46例病人合并症状性癫痫(21.20%),其中建模集中有 32例合并症状性癫痫,验证集中有 14例合并症状性癫痫;发生组昏迷、大脑皮质损坏、脑电图重度异常、颅脑核磁共振成像(MRI)有责任病灶、累及颞叶或额叶、脑脊液单纯疱疹病毒(HSV)(+)占比及脑脊液压力均高于未发生组(P<0.05); logistic多元回归分析,昏迷、大脑皮质损坏、脑电图重度异常、颅脑 MRI有责任病灶、累及颞叶或额叶、脑脊液压力、脑脊液 HSV(+)均是病毒性脑炎合并症状性癫痫的影响因素(P<0.05);经 Bootsrap法进行验证,建模集其一致性指数( C-index)为 0.833,验证集的 Cindex则为 0.830,校正曲线和标准曲线拟合度较好。建模集 ROC曲线下面积(AUC)、灵敏度、特异度分别为 0.84[98%CI:(0.78,0.89)]、79.17%、84.04%,验证集则为 0.81[98%CI:(0.76,0.86)],83.04%,73.64%,提示模型区分度良好。 DCA曲线显示病人根据列线图模型进行风险评估可获得满意的净收益。结论昏迷、大脑皮质损坏、脑电图重度异常、颅脑 MRI有责任病灶、累及颞叶或额叶、脑脊液压力、脑脊液 HSV(+)均是病毒性脑炎合并症状性癫痫的影响因素,综合上述因素针对病毒性脑炎病人构建的列线图预测模型可以较好地个体化预测症状性癫痫的发生,对临床防治症状性癫痫提供指导。 相似文献