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101.
Life expectancy in British Marfan syndrome populations   总被引:2,自引:0,他引:2  
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome.  相似文献   
102.
103.
Summary We examined the specificity and developmental time course of the labelling of retinal ganglion cells in Syrian hamsters by a monoclonal antibody AB5. In adult hamsters, AB5 selectively labelled somata in the ganglion cell layer, dendrites in the inner plexiform layer and axons in the nerve fibre layer. When retinal ganglion cells were retrogradely labelled with Dil prior to AB5 immunocytochemistry, all of the retrogradely labelled retinal ganglion cells in the ganglion cell layer were AB5 immunoreactive, indicating that AB5 labels all classes of ganglion cell in that layer. In retinae depleted of retinal ganglion cells by neonatal optic nerve transections, AB5 did not label any somata or processes, indicating that AB5 specifically labels retinal ganglion cells. During development, AB5 labelling first appeared as a weak staining of cell bodies in the ganglion cell layer on postnatal day 12 (P12; PO=first 24 h following birth) and acquired the staining pattern seen in the adult by postnatal day 14. From the onset of AB5 immunoreactivity, AB5-labelled somata of varying sizes were present across the entire retinal surface. Although AB5 labelled retinal ganglion cell axons in the nerve fibre layer of the retina it did not label the optic nerve or retinal ganglion cell axons in the brain at any age examined. AB5 labelling was also found to be compatible with bromodeoxyuridine immunocytochemistry and, therefore, useful for determining the time of generation of hamster retinal ganglion cells.  相似文献   
104.
Collagenase treatment of cartilage serves as an in vitro model of the pathological collagen degradation that occurs in the disease osteoarthritis (OA). Fourier transform infrared imaging spectroscopic (FT-IRIS) analysis of collagenase-treated cartilage is performed to elucidate the molecular origin of the spectral changes previously found at the articular surface of human OA cartilage. Bovine cartilage explants are treated with 0.1% collagenase for 0, 15, or 30 min. In situ collagen cleavage is assessed using immunofluorescent staining with an antibody specific for broken type II collagen. The FT-IRIS analysis of the control and treated specimens mirrors the differences previously found between normal and OA cartilage using an infrared fiber optic probe (IFOP). With collagenase treatment, the amide II/1338 cm(-1) area ratio increases while the 1238 cm(-1)/1227 cm(-1) peak ratio decreases. In addition, polarized FT-IRIS demonstrates a more random orientation of the collagen fibrils that correlate spatially with the immunofluorescent-determined regions of broken type II collagen. We can therefore conclude that the spectral changes observed in the collagenase-treated cartilage, and similarly in OA cartilage, arise from changes in collagen structure. These findings support the use of mid-infrared spectral analysis, in particular the minimally invasive IFOP, as potential techniques for the diagnosis and management of degenerative joint diseases such as osteoarthritis.  相似文献   
105.
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients.  相似文献   
106.
Morphological and functional plasticity of olfactory ensheathing cells   总被引:12,自引:0,他引:12  
In the primary olfactory pathway, olfactory ensheathing cells (OECs) extend processes to envelop bundles of olfactory axons as they course towards their termination in the olfactory bulb. The expression of growth-promoting adhesion and extracellular matrix molecules by OECs, and their spatially close association with olfactory axons are consistent with OECs being involved in promoting and guiding olfactory axon growth. Because of this, OECs have been employed as a possible tool for inducing axonal regeneration in the injured adult CNS, resulting in significant functional recovery in some animal models and promising outcomes from early clinical applications. However, fundamental aspects of OEC biology remain unclear. This brief review discusses some of the experimental data that have resulted in conflicting views with regard to the identity of OECs. We present here recent findings which support the notion of OECs as a single but malleable phenotype which demonstrate extensive morphological and functional plasticity depending on the environmental stimuli. The review includes a discussion of the normal functional role of OECs in the developing primary olfactory pathway as well as their interaction with regenerating axons and reactive astrocytes in the novel environment of the injured CNS. The use of OECs to induce repair in the injured nervous system reflects the functional plasticity of these cells. Finally, we will explore the possibility that recent microarray data could point to OECs assuming an innate immune function or playing a role in modulating neuroinflammation.  相似文献   
107.
108.
Angiogenic factors prepared from rat Walker 256 mammary carcinoma, (TAF) and activated mouse peritoneal macrophages (MAF), were tested for their ability to stimulate vascularization during healing. They were applied to one of a pair of bilaterally symmetrical, autologous, isotopic, full thickness skin grafts in mice. Blood flow to treated and untreated graft pairs was compared by their uptake of injected 86Rb Cl, at 3 and 7 days after grafting. No difference was detected after treatment with either agent. We conclude that while angiogenic factors are important in vascularization during healing, this normally occurs at a near maximal rate and cannot be further enhanced.  相似文献   
109.
Rhizopus rhizopodiformis has seldom been isolated from human mucormycosis. We report the first subcutaneous abscess to be caused by this fungus. It occurred in a diabetic man and presented as an inguinal mass, suggestive of a hernia, superficial to his cadaveric renal transplant. The fungus was readily isolated from pus inoculated onto blood and chocolate agars after a short incubation. The patient was cured by surgical drainage and treatment with 2.0 g of intravenous amphotericin B. Complete identification of such isolates is recommended.  相似文献   
110.
Protriptyline in obstructive sleep apnea: a double-blind trial   总被引:6,自引:0,他引:6  
We evaluated protriptyline, a nonsedating tricyclic antidepressant, as a treatment for obstructive sleep apnea in a double-blind crossover study of five men. After two weeks of treatment, with no change in body weight, daytime somnolence was markedly reduced and nocturnal oxygenation was improved, although apnea duration and frequency were not significantly decreased. Rapid-eye-movement (REM) stage time as a fraction of the total sleep time was reduced during treatment from 0.231 +/- 0.031 to 0.107 +/- 0.013 (mean +/- S.E.M.) (P less than 0.05). REM apnea time as a fraction of total sleep time was reduced from 0.145 +/- 0.022 to 0.054 +/- 0.006 (P less than 0.05). REM reduction during treatment with protriptyline can account for decreased REM apnea time. Similar decreases in REM stage time and REM apnea duration and similar improvement in oxygenation continued after six months of treatment. In addition, body weight, apnea, and arousal frequency were decreased at this time. Although the obstructive sleep apnea was not resolved, it was reduced. Protriptyline can be effective in patients with sleep apnea when the disorder is not life-threatening.  相似文献   
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