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51.
Facilitating visuospatial attention for the contralateral hemifield by repetitive TMS on the posterior parietal cortex 总被引:2,自引:0,他引:2
Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC. 相似文献
52.
卫生资源优化配置的伦理要求 总被引:1,自引:1,他引:0
1 医学目的和卫生资源的配置卫生资源的配置问题 ,不是一个孤立的问题 ,它是同一定的医学目的联系在一起的 ,一定的医学目的 ,对卫生资源的配置起着导向作用 ,是为一定的医学目的服务的。传统医学由于受科学技术和社会发展的局限 ,以及受传统疾病模式的影响 ,只能把医学的目的定位于对疾病的治疗上 ,向一个消防队员一样 ,哪里有火、火大 ,就把目标投向哪里 ,从而终日疲于奔命 ,和这种医学目的相适应 ,这时的卫生资源配置就只能是把大部分卫生资源用于对疾病的诊治上。随着社会的发展 ,疾病模式发生了显著的变化 ,这种救火式的医疗 ,致使一… 相似文献
53.
By human intestinal bacteria, saikosaponin c was transformed to four metabolites, prosaikogenin E1 (E1) prosaikogenin E2 (E2), prosaikogenin E3 (E3) and saikogenin E. Metabolic time course of saikosaponin c was as follows; in early time, saikosaponin c was converted to E1 and E2, and then these were transformed to saikogenin E via E3. Also, this metabolic pathway was similar to the metabolism of saikosaponin c by rat intestinal bacteria.Bacteroides JY-6 andBacteroides YK-4, the bacteria isolated from human intestinal bacteria, could transform saiko-saponin c to E via E1 (or E2) and E3. However, these bacteria were not able to directly transform E1 and E2 to saikogenin E. Naringin was mainly transformed to naringenin by human intestinal bacteria. The minor metabolic pathway transformed naringin to naringenin via prunin. By JY-6 or YK-4, naringin was metabolized to naringenin only via prunin. 相似文献
54.
The hydrolysis of metampicillin to ampicillin was investigated using high performance liquid chromatography. We developed the simultaneous determination of metampicillin and ampicillin using a Zorbax CN column and 5% acetonitrile and 8% methanol in 0.02 M phosphate buffer (pH 7.0) as mobile phase. Metampicillin was hydrolyzed to ampicillin with half life of 41.5 min at physiological pH and temperature. In acidic pH, metampicillin was rapidly hydrolyzed to ampicillin within a chromatographic separation. 相似文献
55.
A seven-compartment physiologically based pharmacokinetic (PBPK) model was developed to predict biological levels of tetrahydrofuran under various exposure scenarios. Affinities for the tissue were estimated from measurements of liquid-gas partition coefficients for water, olive oil, and blood. Metabolism was assumed to follow a rapid first order reaction. urinary excretion was simulated considering passive reabsorption of tetrahydrofuran in the tubules. The validity of the model was tested by comparison with available experimental and field data. Agreement was satisfactory with all studies available except one, which showed much higher results than expected. The source of this difference could not be identified, but cannot be explained by different exposure conditions, such as duration, concentration, or physical work load. However, it is recommended that this particular study not be used in the establishment of a biological exposure index. Simulation of repeated occupational exposure with the PBPK model allowed the prediction of biological levels that would be reached after repeated exposure at the American Conference of Governmental Industrial Hygienists' threshold limit value, time-weighted average of 200 ppm. For samples taken at the end of the shift, the PBPK model predicts 5.1 ppm for breath, 57 mumol/L (4.1 mg/L) for venous blood, and 100 mumol/L (7.2 mg/L) for urine. 相似文献
56.
Lee SH Shin MS Park WS Kim SY Dong SM Lee HK Park JY Oh RR Jang JJ Lee JY Yoo NJ 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1999,107(11):1013-1019
Cross-linking of Fas and Fas ligand (FasL) induces apoptosis in Fas-bearing cells and regulates apoptosis. Fas is widely expressed in normal human tissues, but FasL expression has been considered to be restricted to lymphoid tissues. Recent studies have demonstrated that FasL is also expressed in some nonlymphoid tissues. To screen the in situ expression of FasL in normal human tissues, immunohistochemistry was performed using paraffin-embedded human tissues. FasL immunostaining was easily detected in testis, neurons, trophoblasts, tonsil, lymph node, Paneth cells, hepatocytes, renal tubular epithelium and bronchial epithelium, consistent with previous reports. Surprisingly, FasL was also expressed in many other cell types, including thymic medulla, skeletal muscle, cardiac muscle, pituitary gland, parathyroid gland, prostate glands, oocytes, epithelium of fallopian tube, endometrial glands, and gastric parietal cells. These findings demonstrate that FasL is widely expressed in human tissues and suggest that wide but cell-type specific expression of FasL may not only be implicated in the regulation of immune homeostasis but also in the regulation of cell death and life in many cell types in vivo. 相似文献
57.
58.
The inhibitory effect of ambroxol on hypochlorous acid-induced tissue damage and respiratory burst of phagocytic cells 总被引:2,自引:0,他引:2
Ambroxol (100 microM and 1 mM) and the thiols (all 1 mM), glutathione, tiopronin and cysteine, significantly attenuated the myeloperoxidase, H(2)O(2) and Cl(-) system-caused destruction of alpha(1)-antiproteinase and the HOCl-induced destruction of collagen, whereas they did not affect the elastase-induced destruction of collagen. Glutathione, tiopronin and cysteine almost completely decomposed both HOCl and H(2)O(2), while ambroxol up to 1 mM did not show a scavenging action on H(2)O(2). Ambroxol (1 to 100 microM) and 1 mM thiol compounds markedly inhibited the HOCl-induced alteration of elastase activity. Thiol compounds significantly attenuated the HOCl production caused by degraded immunoglobulin G-activated neutrophils. Ambroxol depressed superoxide and H(2)O(2) production induced by degraded immunoglobulin G-activated neutrophils and by lipopolysaccharide-activated alveolar macrophages in a dose-dependent manner. The results show that ambroxol may interfere with oxidative tissue damage and decrease proteolytic tissue destruction by attenuation of oxidative stress-induced inactivation of alpha(1)-antiproteinase through both decomposition of HOCl and inhibition of the respiratory burst in phagocytic cells. 相似文献
59.
Jae Chul Jung Ju Cheun Kim Oee Sook Park Bong Suek Jang 《Archives of pharmacal research》1999,22(3):302-305
An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-triflu-oromethylbenzyl oxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3). 相似文献
60.
The results of a survey to determine the first-choice practice intentions of midwestern pharmacy students and to describe and quantify the factors affecting their decisions are reported. Questionnaires were sent to 12 pharmacy schools in American Association of Colleges of Pharmacy District IV and distributed during November 1988 to January 1989. The questionnaires were given to entry-level pharmacy students who were in their final year of study. The students were asked to indicate their preferred practice setting upon graduation and to rate the importance of 21 factors that a pharmacist might consider when selecting a first position. A total of 715 usable responses were received (response rate, 6.75%). OF the respondents, 83.2% were enrolled in B.S. degree programs and 16.8% in entry-level Pharm.D. degree programs. The distribution of first choices of a practice area was as follows: chain community pharmacy, 33.1%; hospital pharmacy, 27.6%; independent community pharmacy, 12.4%; industry, 8.4%; "other," 5.5%; ambulatory-care clinic, 5.2%; graduate school, 3.8%; department store, discount store, or grocery store, 1.7%; home health care, 1.5%; and nursing home, 0.8%. The three factors ranked as most important in affecting the choice of a practice area were personal fulfillment, salary, and the opportunity to use one's abilities and education. The ranking of the factors varied depending on the practice area chosen. Midwestern pharmacy students were most interested in chain community and hospital pharmacy practice settings. Retail-oriented students placed salary concerns first, whereas clinically oriented students emphasized personal fulfillment. These findings have implications for recruitment strategies. 相似文献