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91.
Smith A  Rowan R  McCann M  Kavanagh K 《Biometals》2012,25(3):611-616
The Ag(I) ion has well established anti-bacterial and antifungal properties. Exposure of Staphylococcus aureus to MIC(80) AgNO(3) (3 μg/ml) lead to an increase in the activity of superoxide dismutase, glutathione reductase and catalase at 30 min but activity declined by 60 min. In addition, exposure of cells to this metal ion for 1 h lead to increased expression of a number of proteins such as elongation factors Ts, Tu and G, fructose-bisphosphate aldolase and triosephosphate isomerase but their expression declined following 4 h exposure. ATP binding cassette transporter protein and oligoendopeptidase F showed increased expression at 4 h. While Ag(I) is a potent antimicrobial agent this work demonstrates that S. aureus can mount a short-term protective response to exposure to the metal ion but that this is eventually overcome.  相似文献   
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ABSTRACT: BACKGROUND: With the "ASIA-LINK" program, the European Community has supported the development and implementation of a curriculum of postgraduate psychosomatic training for medical doctors in China, Vietnam and Laos. Currently, these three countries are undergoing great social, economic and cultural changes. The associated psychosocial stress has led to increases in psychological and psychosomatic problems, as well as disorders for which no adequate medical or psychological care is available, even in cities. Health care in these three countries is characterized by the coexistence of Western medicine and traditional medicine. Psychological and psychosomatic disorders and problems are insufficiently recognized and treated, and there is a need for biopsychosocially orientated medical care. Little is known about the transferability of Western-oriented psychosomatic training programs in the Southeast Asian cultural context. METHODS: The curriculum was developed and implemented in three steps: 1) an experimental phase to build a future teacher group; 2) a joint training program for future teachers and German teachers; and 3) training by Asian trainers that was supervised by German teachers. The didactic elements included live patient interviews, lectures, communication skills training and Balint groups. The training was evaluated using questionnaires for the participants and interviews of the German teachers and the future teachers. RESULTS: Regional training centers were formed In China (Shanghai), Vietnam (Ho Chi Minh City and Hue) and Laos (Vientiane). A total of 200 physicians completed the training, and 30 physicians acquired the status of future teacher. The acceptance of the training was high, and feelings of competence increased during the courses. The interactive training methods were greatly appreciated, with the skills training and self-experience ranked as the most important topics. Adaptations to the cultural background of the participants were necessary for the topics of "breaking bad news," the handling of negative emotions, discontinuities in participation, the hierarchical doctor-patient relationship, culture-specific syndromes and language barriers. In addition to practical skills for daily clinical practice, the participants wanted to learn more about didactic teaching methods. Half a year after the completion of the training program, the participants stated that the program had a great impact on their daily medical practice. CONCLUSIONS: The training in psychosomatic medicine for postgraduate medical doctors resulted in a positive response and is an important step in addressing the barriers in providing psychosomatic primary care. The transferability of western concepts should be tested locally, and adaptations should be undertaken where necessary. The revised curriculum forms the basis of training in psychosomatic medicine and psychotherapy for medical students and postgraduate doctors in China, Vietnam and Laos.  相似文献   
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The glypicans compose a family of glycosylphosphatidylinositol-anchored heparan sulfate proteoglycans that may play a role in the control of cell division and growth regulation. So far, six members (GPC1-6) of this family are known in vertebrates. We report the construction of a high-resolution 4 Mb sequence-ready BAC/PAC contig of the GPC5/GPC6 gene cluster on chromosome region 13q32. The contig indicates that, like the GPC3/GPC4 genes on Xq26, GPC5 and GPC6 are arranged in tandem array. Both GPC5 and GPC6 are very large genes, with sizes well over 1 Mb. With a size of approximately 2 Mb, GPC5 would be the second largest human gene identified to date. Comparison of the long range gene organisation on 13q and Xq, suggests that these chromosomes share several regions of homology. Mutations and deletions affecting GPC3 are associated with the Simpson-Golabi-Behmel overgrowth syndrome. Mutational analysis of GPC5 and GPC6 in 19 patients with somatic overgrowth failed to reveal pathologic mutations in either of these genes, but identified several coding region polymorphisms.  相似文献   
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Control of artifacts in plasma adenosine determinations   总被引:1,自引:0,他引:1  
The literature concerning the role of adenosine (ADO) in physiology reveals no agreement about plasma ADO concentrations and suggests two main sources of error in these determinations: rapid ADO uptake by red blood cells or rapid ADO production from ADO nucleotides, which may be released by any cell lysis or platelet aggregation during plasma preparation. We therefore studied ADO concentrations in plasma from normal human forearm venous blood. ADO was determined by a high-performance liquid chromatographic procedure with a sensitivity of 3 nM (original plasma). Observed ADO concentrations ranged from 894 nM to 8.2 nM depending on the conditions of plasma preparation. In plasma prepared in plastic tubes from 4.5 ml of blood drawn into a plastic syringe containing 1.5 ml of an isotonic stopping solution (pH 7.4) containing heparin (60 units ml), dilazep (40 microM), EGTA (40 mM, EDTA (40 mM), erythro-9-(2-hydroxy-3-nonyl) adenine (40 microM), and alpha, beta-methylene adenosine-5'-diphosphate (525 nM), the plasma ADO concentration was 13.3 +/- 1.88 nM (SE) after correction for a simultaneous ADO recovery determination. The mean ADO recovery was 78% +/- 3.39. The mean plasma ADO concentration found by this method of collection and preparation is lower then reported by others. Proper collection methods are required to avoid artifacts when determining plasma ADO concentrations.  相似文献   
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The lymphokine interleukin-4 (IL-4) has been shown to induce dramatic changes in the physiology of resting B cells. We have applied the patch clamp technique in the cell attached and inside/out configurations to resting and IL-4-treated B cells to determine whether specific ion conductances result as a consequence of IL-4 action. We report here that two distinct ion channel events occur in B lymphocytes after treatment with IL-4, (i) induction of an inward rectifying K+ channel that is not observed in untreated cells, and (ii) activation of a large conductance anion channel that is normally silent in non-treated cells in the cell attached patch configuration. These data present the first evidence of a direct effect by IL-4 on ion channels and we suggest roles for these two ionic conductances in IL-4-induced B cell activation.  相似文献   
100.
Aryl sulfotransferases (3'-phosphoadenylsulfate:phenol sulfotransferase, EC 2.8.2.1) catalyze the sulfonation of a wide variety of hydroxyl-containing substrates, including numerous xenobiotics. The chemical diversity of aryl sulfotransferase substrates is in part attributable to the presence of multiple isozymes, each of which has broad substrate specificity. Of the aryl sulfotransferase isozymes in rat liver cytosol, two (designated isozymes I and II) have previously been shown to sulfonate phenolic compounds exclusively and, moreover, have very similar substrate specificity patterns. The recently reported unusually efficient, rapid isozyme I-catalyzed sulfonation of 9-fluorenone oxime (Mangold, J.B., Mangold, B.L.K. and Spina, A. (1986) Biochim. Biophys. Acta 874, 37-43) was therefore unexpected and suggested that aryl oximes may represent a useful class of model compounds to probe isozymic differences in substrate steric and electronic requirements. In the present study, several mono- and diaryl oximes have been prepared and tested as potential substrates for partially purified aryl sulfotransferases I and II from rat liver cytosol. The results indicate that steric factors, specifically planarity and hydroxyl group position, appear to be important requirements for enzyme-catalyzed sulfonation. In addition, although isozymes I and II had comparable activity with diaryl oximes, some striking differences in the ability of these two isozymes to sulfonate both substituted and unsubstituted monoaryl oximes were observed. This dissimilarity is consistent with distinct differences in the active sites of these isozymes.  相似文献   
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