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71.
Chronic Allograft Rejection   总被引:3,自引:0,他引:3  
  相似文献   
72.
73.
Zusammenfassung Störungen der Segmentierung werden bei der Hausmaus durch die Erbfaktoren Crooked tail und Rib fusions wie auch durch weitere Gene hervorgerufen. Eine Phänokopie der Mutation Rib fusions durch Sulfonylharnstoff (Rastinon) wird beschrieben. Als Ursache der beobachteten Wirbel-Rippenmißildungen ist eine Störung der Zellaggregation zu betrachten, die sich durch alle Entwicklungsphasen bis zur knöchernen Fehlbildung auswirkt.Die empfindliche Phase ist die Heraussonderung der Ursegmente aus dem undifferenzierten Mesoblasten. Ihre Beeinflussung, speziell durch hypoglykämische Agentien, wird nach Ort und Zeit analysiert und die Entwicklung der entstehenden Mißbildung untersucht.Es wird die Hypothese aufgestellt, daß in dieser Phase ein erhöhter Energiebedarf besteht, der durch eine Störung der Oxydationsprozesse blockiert werden kann.Ausgeführt mit Hilfe der Stiftung für wissenschaftliche Forschung an der Universität Zürich.  相似文献   
74.
Zusammenfassung Im Lymphknotenausstrich kommen basophile Zellen vor, die weitgehend spezifisch für die Keimzentren der Sekundärknötchen sind und als Germinoblasten bezeichnet werden. Sie sind bei follikulärer lymphatischer Hyperplasie und bei M. Brill-Symmerserheblich vermehrt. Ihre Morphologie wird im einzelnen beschrieben und durch Abbildungen belegt. Eine Unterscheidung von den basophilen Stammzellen, den großen lymphatischen Reticulumzellen der Literatur, ist möglich und nötig, da diese Zellen in Sekundärknötchen und Pulpa gleichermaßen vorkommen.  相似文献   
75.
76.
This study examined verbal-subjective, peripheral and central physiological responses of motor vehicle accident (MVA) survivors with subclinical posttraumatic stress disorder (PTSD), without PTSD symptoms as well as healthy controls. Seven persons of each group were exposed to positive, neutral, accident-related and negative, non-accident-related slides. The verbal-subjective ratings of the slides did not differ between the groups. In contrast to the verbal ratings of the trauma-related materials, the behavioral and physiological responses showed a remarkable dissociation from these reports. The startle responses were enhanced to accident-related slides only in the PTSD group and MVA survivors with PTSD had a significantly lower response to the neutral slides than MVA survivors without PTSD. P200 was lower to positive, neutral and negative slides in the PTSD group compared to both other groups. The late positive complex showed no group-related effects. The data suggest that traumatized persons with PTSD show exaggerated emotional responses to trauma-related stimuli and reduced cognitive responses to several types of stimuli that may interfere with the extinction of the emotional trauma memory.  相似文献   
77.
Gene expression of connective tissue growth factor in adult mouse   总被引:6,自引:0,他引:6  
The connective tissue growth factor (CTGF) is a well-known fibroblast mitogen and angiogenic factor that plays an important role in bone formation during embryogenesis. In the adult, CTGF is involved in wound healing as well as fibrotic and vascular disease. However, little is known about its physiological functions under non-pathological conditions in the adult organism. Here, we describe the cellular site of the CTGF mRNA expression in adult male and female mice as revealed by in situ hybridization histochemistry. Strong and persistent CTGF gene expression was particularly prominent in the mesenchyme of the cardiovascular system (aorta, auricular tissue, renal glomeruli), the mesenchyme surrounding the ovarian follicles or the testicular tubes in the gonadal tissue, and the subcapsular mesenchyme bordering densely innervated parts of whisker hair vibrissae. CTGF hybridization signals were not observed in the mesenchyme of many other organs including gut, muscle, liver or most parts of the lymphatic tissue. Strong expression was also present in the primary (early) ovarian follicles, the epithelium of the deep uterine glands and on myenteric ganglia neurons. These data suggest a selective and continuous mesenchymal function in the gonads and those tissues attracting very strong vascular supply or peripheral innervation. CTGF may also be involved in the cyclical proliferation of the uterine gland epithelium and in the early stages of follicular maturation, as well as in the neuropeptide regulation in the gut, cardiovascular and renal systems.  相似文献   
78.
Summary The cytoarchitectonic parcellation of the rabbit's neocortex has been investigated in 6 hemispheres which had been fixed by perfusion, embedded in paraffin and sectioned at either 9 m or 20 m in various planes. In addition to the classical method of microscopic observation, and automatic scanning procedure using an image analyser for measuring grey level indices was employed. By printing computer plots of various ranges of grey level indices, this method permits visualization of structural differences between various cytoarchitectonic fields. By evaluating the plots, cytoarchitectonic maps can be constructed which are based on objective data and therefore less influenced by subjective judgment than the maps obtained with the classical method. — In some regions the results based on the quantitative method are in agreement with the commonly used maps of Rose (1931), and in other regions widely at variance. It is shown, for instance, that the area striata as defined by Rose (1931) is composed of two distinct fields, viz. areas Oc 1 and 2, which are separated from each other in the rostro-caudal direction. These and other findings are described in detail, compared with the observations of Rose (1931), and related to the literature on functional localization in the rabbit's neocortex. Attention is drawn to the fact that the results obtained in 6 hemispheres leave no doubt that individual variations in size and shape of the entire hemisphere as well as of the various cytoarchitectonic fields do occur, and will have to be taken into account if cytoarchitectonic maps such as those published in the present paper are to be used in the context of experimental work.  相似文献   
79.
Postural and eye-blink reactions to acoustic startle probes were examined in 24 volunteers, who completed two blocked conditions (baseline, startle). A postural reaction during the startle condition demonstrated a reflexive movement in the anterior-posterior direction, which was not observed during the baseline condition. This reflexive response was positively associated with the eye-blink reflex, such that larger blink magnitude related to greater posterior movement. These findings were not observed for postural movements in the medial-lateral direction. The results suggest that a measurable postural reaction may be observed following a startling acoustic stimulus, which may reflect generalized bodily flexion associated with a preparatory behavioral response.  相似文献   
80.
To assess the general effects of protein kinase C (PKC) activation on cell membrane receptor mobility in human neutrophilic polymorphonuclear leukocytes (PMNLs), the lateral diffusion of fluoresceinated succinylated wheat germ agglutinin (S-WGA-FITC)-labeled membrane glycoconjugates was measured using fluorescence recovery after photobleaching (FRAP). Activation of PKC was achieved by incubating the PMNLs with different concentrations (5–100 nM) of phorbol myristate acetate (PMA). The membrane effects of dimethyl sulfoxide (DMSO), another possible membrane perturbant, were also studied. We found that PMA treatment ( 10 nM) increased the glycoconjugate diffusion coefficient (D) 2–2.5-fold. The mobile fraction (R) remained constant, around 30%. With DMSO, no effect on the diffusion was seen. The increase in lateral mobility due to cell stimulation with PMA was totally inhibited by catalase (200 units/ml) but only partly with superoxide dismutase (2000 units/ml). Exogenous hydrogen peroxide (0.01–5 mM) had no effect on glycoconjugate mobility in unstimulated cells. We therefore propose that activation of PKC mediates augmented mobility of glycoconjugate receptors in PMNL, a reaction that seems to be critically dependent on formation of reactive oxygen metabolites. The results indicate that endogenous formation of reactive metabolites upon receptor stimulation may have a general effect on receptor mobility.  相似文献   
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