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131.
132.
田宝 《中国健康心理学杂志》2003,11(4):284-285,292
目的 探讨心理疗法对防治SARS的作用,方法 本文综合国内外心理疗法研究成果,提出了应对非典的心理处方:“接纳恐惧,顺其自然;平衡思维,端正认识;积极暗示,增强信心;切已体察,心理常态”;结果 从原理上解释其发生作用的机制,明确心理处方的实际操作,提出具体的步骤和要点,并对日常生活中的不妥做法进行了剖析。结论 采用心理疗法可增强抗击“非典”的信心及提高免疫功能。 相似文献
133.
许多重要的细胞过程如信号转导、转运、细胞运动以及多数调节机制均由蛋白-蛋白之间的相可作用介导,蛋白质之间的相互作用在物理上是通过在两个相互作用蛋白之间形成接触面的短残基序列来实现。识别蛋白-蛋白相互作用位点,以及检测相互作用氨基酸残基之间的特异性与强度特异性,是一个具有重要应用前景的课题,它的应用范围从理性的药物设计到代谢和信号转导网络的分析。虽然有不少准确度不断提高的实验技术和计算方法来检测蛋白质之间的相互作用,但很少有方法能够精确地指出参与蛋白质相互作用的特定残基及其位置,而这些信息是将相互作用数据直接应用于药物开发所必需的。随着生物信息学和计算生物学的发展,通过研究已知蛋白-蛋白相互作用位点的这些不同特征.出现了一些利用序列与结构信息顶测蛋白-蛋白相互作用位点的计算方法。本文简要介绍了近年来在顶测蛋白-蛋白的相互作用位点方面取得一定进展的计算方法,包括基于基因组信息的计算方法、基于蛋白质初级序列的计算方法以及基于蛋白复合物结构信息的计算方法。虽然这些方法在过去儿年里取得了显著的进展,但是大多数在这方面的研究仍处于起步阶段.而现在数据库的不足和实验技术的缺陷对计算预测方法的进一步发展和公平性评价也存在着较大的影响,要提高蛋白-蛋白相巨作用位点预测的鲁棒性与可靠性,仍要有很多的工作要做。(发表在这里的是第一部分) 相似文献
134.
我们用锥板式粘度计从低切到高切、从高切到低切、以及先在80s-1下旋转60s、静止100s、再从低切到高切三种方法,测定了Vister大白鼠在低切变率为5.75-1时的血液粘度。组间对照显示,三种测法所得低切血液粘度之间无显著差异,表明这些方法均可用来测量低切血液粘度。从低切稳定性来看,第二种测法最好。就用粘度法反映红细胞聚集性而言,第一种测法比较合适。 相似文献
135.
Bruce S. Seal Robert B. Klieforth Anthony E. Castro Werner P. Heuschele 《Methods in Cell Science》1988,11(2):49-55
Summary Cultures of fetal aoudad sheep kidney (FAK), bovine embryonic lung (BEL), and African green monkey kidney (Vero) cells were compared for differential replication of alcelaphine herpesviruses. Cell-free virus appears more rapidly when infected cells are incubated at 33° C rather than at 37° C. Events in the replication and morphologic development of several alcelaphine herpesvirus isolates have been documented using light and electron microscopy. Techniques for indirect immunofluorescence and serum virus neutralization are described. When virus free of host-cell contaminants is desired for biochemical analysis, virus isolates are initially purified on sucrose gradients and then further purified by density gradient centrifugation in Percoll. 相似文献
136.
Ho PL Tsang DN Que TL Ho M Yuen KY 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(3):237-240
Three tests, the disk diffusion test, the double-disc synergy test and the inhibitor-potentiated disc diffusion test, were compared for their abilities to detect production of extended-spectrum beta-lactamases (ESBL) in 702 Escherichia coli and 472 Klebsiella spp. strains from four hospitals. Eleven percent E. coli and 13% Klebsiella spp. were found to produce ESBL. As an indicator of ESBL activity, the sensitivities of the five extended-spectrum beta-lactams were as follows: cefotaxime (100%), cefpodoxime (99.3%), ceftriaxone (98.6%), aztreonam (93%) and ceftazidime (57.7%) when interpreted using the National Committee for Clinical Laboratory Standards criteria. Their positive predictive values ranged from 67.8-83.8%. Both the inhibitor-potentiated disc diffusion test and the double-disc synergy test (at three inter-disc widths of 20, 25 and 30 mm) were capable of identifying all the ESBL-producers. However, at a single inter-disc width of 30 mm, the double-disc synergy test has limited sensitivity (83.8%). As a second test for confirming ESBL activity in strains with reduced susceptibility to beta-lactams, the inhibitor-potentiated disc diffusion test is therefore a simple and reliable option. 相似文献
137.
Summary A technique for culturing small quantities of mammalian cells on modified microscope slides is described. The modified microscope slides were Bellco Glass, Inc., toxoplasmosis slides and the cell cultures used were early passage bovine embryonic lung cells and continuous cell lines of porcine and canine origins. The slide cell cultures were either uninfected or infected with selected viruses or the obligate intracellular protozoanEncephalitozoon caniculi for utilization in direct and indirect fluorescent antibody testing or in peroxidase antiperoxidase immunosorbant assays. 相似文献
138.
Frances M. Dewey David R. Twiddy Sarah I. Phillips Margaret J. Grose Peter W. Wareing 《Food and Agricultural Immunology》1992,4(3):153-167
A sensitive, specific, quantitative enzyme‐linked immunosorbent assay (ELISA) has been developed that can be used to determine the extent of mycelial growth of a sporulating thermophilic fungus, Humicola lanuginosa on the surface of rice grains. The assay employs a monoclonal antibody EC6, developed in a previous study, which does not recognize spores of the fungus. Using antigen‐coated wells, a direct linear relationship was established between dilutions of extracts from freeze‐dried mycelium (0.5 to 3 μg/ml) and absorbance values but to eliminate day‐to‐day variations it was found to be necessary to run a dilution series, prepared from stock freeze‐dried mycelium, with every test sample. The ELISA method was compared with conventional quantitative methods. Estimates of total mycelial length in freeze‐dried material by ELISA were found to be in the same order of magnitude as those determined by ergosterol and a theoretical calculation. The ELISA method also compared favourably with direct linear measurements (by photomicrography) of live mycelium present in aliquots from homogenates of a 1 cm2 plug taken from a plate but estimates of the latter by the dilution plate count method were much lower. In assays with inoculated rice grains, the quantitative ELISA method proved more sensitive than either the ergosterol method or direct plating of surface‐sterilized grains. The ELISA method also has the advantage of being highly specific and quick to conduct. 相似文献
139.
Serum hepatitis B virus DNA in healthy HBsAg-negative Chinese adults evaluated by polymerase chain reaction 总被引:3,自引:0,他引:3
L N Shih J C Sheu J T Wang G T Huang P M Yang H S Lee J L Sung T H Wang D S Chen 《Journal of medical virology》1990,32(4):257-260
Serum hepatitis B virus (HBV) DNA was assayed using polymerase chain reaction, in 107 HBsAg-negative normal Chinese subjects. The results showed that eight subjects (7.5%) had HBV DNA. In the subgroup with antibody to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc), 7.3% (5/68) were positive for HBV DNA; HBV DNA was not detected in six individuals with anti-HBs only and in nine with anti-HBc only. In four persons with anti-HBc and anti-HBe, one had HBV DNA. In 20 subjects negative for all hepatitis B serological markers, two (10%) were found to have HBV DNA. This study indicates that serological markers are not adequate to rule out HBV infection, and it further implies that present blood donor screening methods may need improving. 相似文献
140.
Gregory K. M. Giolli R. A. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,60(3):501-508
Summary The neurons of the medial terminal nucleus (MTN) of the accessory optic system (AOS) have been studied in the rat, rabbit and cat in Golgi-Cox and Golgi-Kopsch impregnated brain sections. The present anatomical findings permit a division of the MTN of these species into dorsal and ventral components (MTNd, MTNv), in agreement with other investigations. The MTNd contains predominantly linear-bipolar and linear-multipolar shaped neurons with cell bodies that measure in the range of 25–50 m. These neurons have 2 to 4 primary dendrites which, along with their smaller dendritic branches, are oriented in the plane of the long axis of the MTN (i.e. from ventromedial to dorsolateral). These linear-bipolar and linear-multipolar cells represent 70–80% of the neurons of the MTNd as seen in the Golgi impregnated sections. The remaining 20–30% of the MTNd neurons are nearly all multipolar in shape with somata measuring in the range of 15–25 m. An occasional multipolar neuron is larger, has a soma that measures around 30–60 m and has dendrites which extend outward from the cell body to cover large areas of the MTNd. There was considerable extension of the dendrites of MTNd neurons into the MTNv; however, the dendrites of MTNd neurons were not observed extending into the adjacent substantia nigra (SN) or ventral tegmental area (VTA) of Tsai (1925). Conversely, the dendrites of neurons in the neighboring SN and VTA course along the borders of the MTN but only occasionally extend into the MTN. The neuron population of the MTNv consists almost entirely of small-multipolar shaped cells with somata measuring from 15–25 m and dendritic trees resembling those described for multipolar cells of the MTNd. A small number of neurons of the ventral division are medium-multipolar in shape with cell bodies that measure approximately 30–60 m. Typically, these cells have several dendrites which extend ventrally within the MTNv and one or more dendrites that extend either across the MTNv or dorsally into the MTNd. Only a few linear-bipolar and linear-multipolar neurons were observed in the MTNv. The present findings are discussed in relation to anatomical, physiological, and histochemical studies on the MTN.Abbreviations to Figures CP
Cerebral Peduncle
- DTN
Dorsal Terminal Nucleus
- LG
Lateral Geniculate Nucleus
- LP
Lateral Posterior Nucleus
- MG
Medial Geniculate Nucleus
- ML
Medial Lemniscus
- MTNd
Medial Terminal Nucleus, dorsal division
- MTNv
Medial Terminal Nucleus, ventral division
- NTO
Nucleus of the Optic Tract
- PA
Anterior Pretectal Nucleus
- pn
Nucleus Paranigralis
- PP
Posterior Pretectal Nucleus
- Pul
Pulvinar
- PO
Olivary Pretectal Nucleus
- RN
Red Nucleus
- SGS
Stratum Griseum Superficiale, Superior Colliculus
- SN
Substantia Nigra
Supported by USPHS research grant EYO3642 from the National Eye Institute 相似文献