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21.
CGS 10746B: an atypical antipsychotic candidate that selectively decreases dopamine release at behaviorally effective doses 总被引:1,自引:0,他引:1
C A Altar A M Wasley J Liebman S Gerhardt H Kim J J Welch P L Wood 《Life sciences》1986,39(8):699-705
CGS 10746B, a benzothiadiazepine, has a behavioral profile in mice and monkeys similar to the atypical antipsychotic clozapine. Unlike clozapine, CGS 10746B suppresses dopamine neuron firing rates and, when administered at behaviorally effective doses by the oral or intraperitoneal route, decreases neostriatal dopamine release without changing dopamine metabolism or occupying D2 receptors. CGS 10746B is the first atypical antipsychotic candidate that selectively decreases dopamine release. 相似文献
22.
Identification of zona binding proteins of rabbit, pig, human, and mouse spermatozoa on nitrocellulose blots 总被引:2,自引:0,他引:2
M G O'Rand J E Matthews J E Welch S J Fisher 《The Journal of experimental zoology》1985,235(3):423-428
Mammalian fertilization is a multi-step process with different requirements for specificity at each step. In the present report we have examined the binding of spermatozoa to homologous and heterologous zonae pellucidae. The homologous zona binding proteins (ZBP) of ejaculated rabbit, pig and human spermatozoa and epididymal mouse spermatozoa have been identified. The rabbit's ZBPs have relative molecular weights (MW) of 32K, 18K, 16K and 14K; the pig's major ZBP is 16K while human spermatozoa bind human zona protein at 17K and 18K. Mouse sperm ZBPs are 19K, 18K and 16K. 相似文献
23.
The common 90-kd protein component of non-transformed ''8S'' steroid receptors is a heat-shock protein. 总被引:44,自引:6,他引:38 下载免费PDF全文
M G Catelli N Binart I Jung-Testas J M Renoir E E Baulieu J R Feramisco W J Welch 《The EMBO journal》1985,4(12):3131-3135
Non-transformed steroid receptors have an approximately 8S sedimentation coefficient that corresponds to an oligomeric structure of 250-300 kd which includes a non-hormone binding 90-kd protein. A monoclonal antibody BF4 raised against the purified, molybdate-stabilized, 8S progesterone receptor (8S-PR) from chick oviduct, recognizes 8S forms of all steroid hormone receptors. BF4 was found specific for a 90-kd protein present in great abundance in all chicken tissues, including that present in 8S-forms of steroid receptors. Here, using immunological and biochemical techniques, we demonstrate that this ubiquitous BF4-positive 90-kd protein is in fact the chicken 90 kd heat-shock protein (hsp 90): it increased in heat-shocked chick embryo fibroblasts, and displayed identical migration in two-dimensional gel electrophoresis and the same V8 peptide map as the already described hsp 90. We discuss the possibility that the interaction between hsp 90 and steroid hormone-binding subunits may play a role in keeping the receptor in an inactive form. 相似文献
24.
Rapid purification of mammalian 70,000-dalton stress proteins: affinity of the proteins for nucleotides. 总被引:83,自引:13,他引:70 下载免费PDF全文
A new and rapid purification procedure has been developed for the mammalian 70,000-dalton (70-kDa) heat-shock (or stress) proteins. Both the constitutive 73-kDa protein and the stress-induced 72-kDa protein have been purified by a two-step procedure employing DE52 ion-exchange chromatography followed by affinity chromatography on ATP-agarose. The two proteins, present in approximately equal amounts in either the 12,000 X g supernatant or pellet of hypotonically lysed heat-shock-treated HeLa cells, were found to copurify in relatively homogenous form. The purified proteins were covalently labeled with the fluorescent dye tetramethylrhodamine isothiocyanate, and the fluorescently labeled proteins were introduced back into living rat embryo fibroblasts via microinjection. The microinjected cells maintained at 37 degrees C showed only diffuse nuclear and cytoplasmic fluorescence. After heat-shock treatment of the cells, fluorescence was observed throughout the nucleus and more prominently within the nucleolus. This result is consistent with our earlier indirect immunofluorescence studies which showed a nuclear and nucleolar distribution of the endogenous 72-kDa stress protein in heat-shock-treated mammalian cells. The result also indicates that, for at least the 72-kDa protein, (i) the protein has been purified in apparently "native" form and (ii) its nucleolar distribution is stress dependent. 相似文献
25.
L Berman G de Lacey E Twomey B Twomey T Welch R Eban 《BMJ (Clinical research ed.)》1985,290(6466):421-422
The assessments by radiographers of 1628 consecutive patients referred for radiography in the casualty department were analysed. The radiographers missed abnormalities in the radiographs in 68 of the cases. Casualty officers missed abnormalities in 63 cases, but only 35 patients were common to both groups. Twenty eight of the radiographs interpreted wrongly by casualty officers were interpreted correctly by radiographers; 16 of these 28 were thought by the accident and emergency consultant to be clinically important. It is suggested that a system whereby radiographers signal abnormalities should be standard practice. 相似文献
26.
Determination of the specific radioactivity of fatty acids separated as their methyl esters by gas-liquid chromatography 总被引:1,自引:0,他引:1
Free or combined (3)H-labeled fatty acids are converted to their methyl-(14)C esters or, if labeled with (14)C, to their methyl-(3)H esters. For a given specific radioactivity of the methyl group, the nuclide ratio in the esters separated by GLC is a direct measure of the specific radioactivity of the fatty acids, and quantitative collection is unnecessary. Methods of methylation with minimum quantities of labeled methanol, and of deriving nuclide ratios from channel ratios in a scintillation spectrometer, are given. 相似文献
27.
28.
Effect of Carbon Dioxide on the Aspartic Acid Requirement for Proteinase Biosynthesis by Streptococcus faecalis var. liquefaciens 总被引:2,自引:1,他引:1 下载免费PDF全文
Non-proliferating cells of Streptococcus faecalis var. liquefaciens required aspartic acid for proteinase biosynthesis in the absence of CO(2) but not in the presence of CO(2). 相似文献
29.
The production of short-lived radioactive gases for medical studies is discussed with regard to the chemical reactions in suggested targets. The chemistry of target materials was studied by using the technique of radio-gas-liquid partition chromatography to analyze the product gases. Based on the chemistry of the reactions of oxygen-15 in oxygen-nitrogen mixtures, and carbon-11 in boric oxide, targets were designed for the production of oxygen-15-labeled oxygen, oxygen- 15-labeled carbon monoxide, and carbon-11-labeled carbon monoxide in high yields and high radio-chemical purity. 相似文献
30.