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41.
Diffusion MRI investigations in schizophrenia provide evidence of abnormal white matter (WM) microstructural organization as indicated by reduced fractional anisotropy (FA) primarily in interhemispheric, left frontal and temporal WM. Using tract-based spatial statistics (TBSS), we examined diffusion parameters in a sample of patients with severe chronic schizophrenia. Diffusion MRI data were acquired on 19 patients with chronic severe schizophrenia and 19 age- and gender-matched healthy controls using a 64 gradient direction sequence, (b=1300 s/mm2) collected on a Siemens 1.5T MRI scanner. Diagnosis of schizophrenia was determined by Diagnostic and Statistical Manual for Mental Disorders 4th Edition (DSM-IV) Structured Clinical Interview for DSM disorder (SCID). Patients were treatment resistance, having failed to respond to at least two antipsychotic medications, and had prolonged periods of moderate to severe positive or negative symptoms. Analysis of diffusion parameters was carried out using TBSS. Individuals with chronic severe schizophrenia had significantly reduced FA with corresponding increased radial diffusivity in the genu, body, and splenium of the corpus callosum, the right posterior limb of the internal capsule, right external capsule, and the right temporal inferior longitudinal fasciculus. There were no voxels of significantly increased FA in patients compared with controls. A decrease in splenium FA was shown to be related to a longer illness duration. We detected widespread abnormal diffusivity properties in the callosal and temporal lobe WM regions in individuals with severe chronic schizophrenia who have not previously been exposed to clozapine. These deficits can be driven by a number of factors that are indistinguishable using in vivo diffusion-weighted imaging, but may be related to reduced axonal number or packing density, abnormal glial cell arrangement or function, and reduced myelin.  相似文献   
42.
Peripheral blood stem cells (PBSCs) mobilized with high-dose chemotherapy and hematopoietic growth factors are now widely used to support myeloablative therapy of multiple myeloma and effect complete remissions in up to 50% of patients with apparent extension of event- free and overall survival. Because tumor cells are present not only in bone marrow, but also in virtually all PBSC harvests, it is conceivable that autografted myeloma cells contribute to relapse after autotransplants. In this study, the kinetics of mobilization of normal hematopoietic stem cells were compared with those of myeloma cells present in PBSC harvests of 12 patients after high-dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor administration. CD34+ and CD34+Lin-Thy+ stem cell contents were measured by multiparameter flow cytometry, and myeloma cells were quantitated by immunostaining for the relevant Ig light chain and by a quantitative polymerase chain reaction for the myeloma-specific CDRIII sequence. Results indicated marked heterogeneity in the percentages of mobilized stem cells among different patients (0.1% to 22.2% for CD34+ cells and 0.1% to 7.5% for CD34+Lin-Thy+ cells, respectively). The highest proportions of hematopoietic progenitor cells were observed early during apheresis, with 9 of 12 patients mobilizing adequate amounts of CD34+ cells for 2 autotransplants (> 4 x 10(6)/kg) within the first 2 days, whereas peak levels (percent and absolute numbers) of myeloma cells were present on days 5 and 6 (0.5% to 22.0%). During the last days of collection, mobilized tumor cells exhibited more frequently high labeling index values (1% to 10%; median, 4.4%) and an immature phenotype (CD19+). The differential mobilization observed between normal hematopoietic stem cells and myeloma cells can be exploited to reduce tumor cell contamination in PBSC harvests.  相似文献   
43.
The ganglioside pattern of both SV40- and polyoma virus-transformed mouse cell lines differs from that of the parent cell lines or of cell lines that have transformed spontaneously in tissue culture. This is manifested by a dramatic decrease of gangliosides with an oligosaccharide chain larger than sialyllactose. Present investigations indicate that this change probably cannot be attributed to excessive catabolism of gangliosides, but is caused by impaired synthesis of tri- and tetrahexosyl gangliosides in the virus-transformed cell lines. We present evidence for the block of a required step for the biosynthesis of these ganglioside homologs. The block involves the enzyme catalyzing the transfer of N-acetylgalactosamine from uridine diphosphate N-acetylgalactosamine to hematosides (N-glycolylneuraminyl or N-acetylneuraminylgalactosylglucosyl ceramide). This well-defined enzymatic change opens the way for studies of the biochemical mechanism of the alteration of cell membranes which occurs after transformation by the tumorigenic DNA viruses polyoma and SV40.  相似文献   
44.
Normal microbial flora support the health of the host by diverse mechanisms. When antibiotics, stress, disease or medications disrupt normal microflora, the ability to ward off infection by pathogens is compromised. The use of beneficial microbes (also known as biotherapeutic agents, probiotics, synbiotics) has been shown to be an effective therapeutic agent for some diseases. Various types of diarrhoea (antibiotic-associated diarrhoea, Clostridium difficile disease, traveller's diarrhoea) are most responsive to these beneficial microbes. Serious risks associated with these microbes are largely theoretical at this point, but the risks need to be studied as the use of these beneficial microbes increases in popularity. Beneficial microbes are living organisms used as therapeutic agents to restore the health of the host in times when normal microflora have been disturbed. The efficacy to prevent or treat diarrhoea has been documented in multiple large, placebo-controlled, blinded clinical trials with only a few of these beneficial microbes. Risks of these beneficial microbes are limited, but potential risks have not been extensively studied in large numbers of patients.  相似文献   
45.
46.
Cancer therapies that generate T cell-based anti-cancer immune responses are critical for clinical success and are favored over traditional therapies. One way to elicit T cell immune responses and generate long-lasting anti-cancer immunity is through induction of immunogenic cell death (ICD), a form of regulated cell death that promotes antigenicity and adjuvanticity within dying cells. Therefore, research in the last decade has focused on developing cancer therapies which stimulate ICD. Herein, we report novel photodynamic therapy (PDT) compounds with immunomodulatory and ICD inducing properties. PDT is a clinically approved, minimally invasive anti-cancer treatment option and has been extensively investigated for its tumor-destroying properties, lower side effects, and immune activation capabilities. In this study, we explore two structurally related ruthenium compounds, ML19B01 and ML19B02, that can be activated with near infrared light to elicit superior cytotoxic properties. In addition to its direct cell killing abilities, we investigated the effect of our PSs on immunological pathways upon activation. PDT treatment with ML19B01 and ML19B02 induced differential expression of reactive oxygen species, proinflammatory response-mediating genes, and heat shock proteins. Dying melanoma cells induced by ML19B01-PDT and ML19B02-PDT contained ICD hallmarks such as calreticulin, ATP, and HMGB1, initiated activation of antigen presenting cells, and were efficiently phagocytosed by bone marrow-derived dendritic cells. Most importantly, despite the distinct profiles of ICD hallmark inducing capacities, vaccination with both PDT-induced dying cancer cells established anti-tumor immunity that protected mice against subsequent challenge with melanoma cells.  相似文献   
47.
48.
This paper reviews a triangular relationship in which a state mental health administration, a university, and a local mental health authority (and by extension, community mental health programs) co-exist. The relationship is based on mutual trust and interdependence, both of which are reinforced when certain key positions are developed such that individuals can work in two or more of the three arenas. It is essential that representatives of each group be encouraged to recognize the needs and assets of the other two groups. Specific examples of the benefits of this arrangement are described based on experiences in the state of Oregon.This work is supported in part by NIMH grant number P50 MH43458 to the Western Mental Health Research Center at Oregon Health Sciences University. Dr. McFarland is Burroughs-Wellcome Scholar in Pharamacoepidemiology.  相似文献   
49.
New diagnostic criteria for multiple sclerosis integrating magnetic resonance image assessment with clinical and other paraclinical methods were introduced in 2001. The "McDonald Criteria" have been extensively assessed and used since 2001. New evidence and consensus now strengthen the role of these criteria in the multiple sclerosis diagnostic workup to demonstrate dissemination of lesions in time, to clarify the use of spinal cord lesions, and to simplify diagnosis of primary progressive disease. The 2005 Revisions to the McDonald Diagnostic Criteria for MS should simplify and speed diagnosis, whereas maintaining adequate sensitivity and specificity.  相似文献   
50.
Reflex responses recorded from the upper and lower divisions of the human orbicularis oris muscle were studied as a function of the site of stimulation. Stimuli were applied to 11 sites, ranging from the glabrous skin of the upper and lower lip vermilion borders to the hairy skin of the cheek. Highly localized, innocuous mechanical stimuli were created by displacing a servo-controlled probe over the surface of the perioral skin. Reflex response amplitude was strongly dependent on the site of stimulation. Stimulation of some sites, for example the ipsilateral corner of the mouth, the chin, and cheek, produced no responses, whereas stimulation of other sites, particularly the ipsilateral vermilion borders, produced large reflex responses. Changes in response amplitude as a function of stimulation site were the same for the upper lip and lower lip muscle recordings, with the largest responses at both recording sites produced by stimulation of the ipsilateral upper lip vermilion border. These results suggest that the upper and lower divisions of orbicularis oris share common synaptic drive, at least from inputs generated via reflex pathways, and that the upper vermilion border may be more densely innervated with mechanoreceptors than the lower. The latter hypothesis was supported by an additional experiment examining two-point discrimination thresholds for the glabrous skin of the upper and lower lips. Two-point thresholds were significantly smaller for the upper compared with the lower lip vermilion border.  相似文献   
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