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The purpose of this study was to analyze contralateral reinnervation of the facial nerve in eight patients with complete facial palsy after surgery or trauma and seven healthy volunteers. All patients had contralateral reinnervation of facial muscles as demonstrated by electrical nerve stimulation versus none of the control subjects. Four patients had facial muscle movements at the site of the damaged nerve. In one patient this was entirely the result of contralateral reinnervation, whereas the other three patients had innervation both ipsilaterally and contralaterally. This implies that renewed facial muscle activity should be examined considering the origin of the reinnervation, either contralateral or ipsilateral. Contralateral reinnervation is a common phenomenon after total facial palsy and can occur alongside ipsilateral reinnervation. It can be mistaken for adequate reinnervation of the damaged nerve, causing postponement of dynamic reconstruction therapy.  相似文献   
3.
Three-dimensionally localized proton-decoupled phosphorus-31 magnetic resonance (MR) spectroscopy of skeletal and cardiac muscle was performed in six patients with systemic sclerosis. Cardiac (n = 9) and skeletal (n = 6) spectra were also obtained in healthy volunteers. Metabolite ratios and intracellular pH were determined from the spectra of skeletal and cardiac muscle. The phosphocreatine-to-adenosine triphosphate ratio was normal for both skeletal and cardiac muscle in patients with systemic sclerosis. The pH values of skeletal muscle were similar in patients and control subjects (7.13 ± 0.02 vs 7.12 ± 0.01, respectively). In skeletal muscle, the inorganic phosphate-to-phosphocreatine ratio in patients was increased relative to that of control subjects (0.106 ± 0.014 vs 0.086 ± 0.006, respectively; P =.02). P-31 MR spectroscopy showed no abnormalities in the myocardium of patients with systemic sclerosis. Assessment of the inorganic phosphate-to-phosphocreatine ratio in peripheral skeletal muscle may be helpful for assessing disease activity.  相似文献   
4.
In a selected group of 8 patients with progressive alopecia areata (AA) leading to AA universalis, immunological aspects (in the peripheral blood and the tissue) were studied during the period of the intitial attack of the disease. The peripheral T-cell helper/suppressor ratio appeared not to be a reliable parameter for the disease activity. The intrabulbar and peribulbar distribution of T-cells, Langerhans cells and of HLA-DR expression in and around the anagen hair follicles in the progressive areas of the disease (region of exclamation-mark hairs) may suggest a T-cell-mediated injury primarily in the peribulbar regions of the follicles. The data presented tend to support the possibility that in the early development of AA, the dermal pailla (capillary network?) may be the prime target of immunologic injury.  相似文献   
5.
MALARIA RESULTS IN TWO SEEMINGLY PARADOXICAL PERTURBATIONS OF THE IMMUNE RESPONSE: polyclonal B-cell activation and immunosuppression. To determine what immunoregulatory role mediators secreted by adherent cells might play in these alterations, we cultured adherent cells from uninfected mice and from mice at different times during infection with Plasmodium berghei or P. yoelii. Culture supernatants obtained from these cells were tested for their ability to enhance the in vitro proliferative responses of thymocytes to suboptimal concentrations of concanavalin A or to inhibit the mitogen-stimulated proliferation of normal spleen cells. Supernatants obtained from adherent cells of mice early in infection (days 1 to 3) contained significantly elevated levels of enhancing activity which on Bio-Gel P-100 chromatography resembled lymphocyte-activating factor. Later in infection (days 4 and 5), these supernatants contained inhibitory activity. Normal adherent cells, when cocultivated in vitro with parasitized erythrocytes, ingested parasite debris and were stimulated to produce the enhancing factor. At high parasite/adherent-cell ratios, cells elaborated an inhibitory factor. These findings suggest that during malaria, adherent cells are converted from a nonspecific helper role to a nonspecific suppressor role. This modulation in function may be due to the direct interaction between adherent cells and parasitized erythrocytes.  相似文献   
6.
The C-C chemokine RANTES, a T lymphocyte chemoattractant, is considered an important mediator of inflammation, allergy, and host defense against HIV-1 infection. In this study, we investigated the modulation of binding of RANTES to T lymphocytes. Human peripheral blood CD3+ T cells, when freshly isolated from buffy-coat blood, expressed a considerable number of high-affinity binding sites for RANTES. These cells also showed significant chemotactic migration in response to RANTES in vitro. After 6–15 h incubation at 37°C, the binding of RANTES, but not of macrophage inflammatory protein-1α (MIP-1α) or of monocyte chemotactic protein-3 (MCP-3), consistently increased. Scatchard analyses indicated that the number of binding sites for RANTES increased about threefold by 15 h without any change in the affinity. The increase in RANTES binding was no longer detected by 24 h. This increase in the specific binding was mainly attributable to CD4+ T cells and was not associated with increased chemotactic activity of these cells in response to RANTES. Incubation with anti-CD3 antibody for 15 h markedly reduced the binding capability of T cells for RANTES and was associated with decreased chemotactic activity. On the other hand, when T cells were incubated with interleukin-2 (IL-2) for 1 week, the specific binding for all three C-C chemokines, RANTES, MIP-1α, and MCP-3 was markedly increased in comparison to cells cultured in the absence of IL-2. These results suggest that the expression of binding sites on T cells for RANTES is differentially modulated, indicating the existence of novel receptors for RANTES that do not bind MIP-1α.  相似文献   
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Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms.  相似文献   
9.
The reliability and validity of the RAND 36-Item Health Survey 1.0 were investigated in a population sample of 1,063 inhabitants of a Dutch township, all age 17or older. Confirmatory factor analysisonly partly supported the internal structure of the RAND 36-Item Health Survey 1.0. The internal consistency of the instrument was high. Pointing to high convergent validity, a multitrait-multimelhod matrix revealed that the RAND-36 scales showed higher correlations with corresponding scales from other instruments than with noncorresponding scales. However, indicating low discriminant validity, some of these correlations did not exceed the intercorrelations among the RAND-36 scales. Multivariate analysis of variance (MANOVA) showed significant effects of age for physical functioning, role limitations (physical problem), general health perception and pain, and significant effects of education on physical functioning and general health perception. Significant sex differences were found for mental health only. The results of this study on the psychometric properties of the RAND 36-Item Health Survey 1.0 seem promising. There is a need for further studies investigating its factor structure and cross-cultural equivalence.  相似文献   
10.
Hyper-IgD and periodic fever syndrome (HIDS) and mevalonic aciduria are autosomal recessive disorders characterized by recurrent episodes of fever and generalized inflammation. Both syndromes are caused by specific mutations in the gene encoding mevalonate kinase (MK), resulting in a depressed enzymatic activity mainly due to reduced protein levels. We studied the effect of temperature on the activity of wild-type and several mutant MKs in fibroblasts. All fibroblast cell lines from HIDS patients and harbouring the common V377I MVK allele displayed substantially higher MK activities at 30 degrees C as compared to 37 degrees C. As shown by temperature inactivation experiments this resulted in a protein nearly as stable as in control cell lines, indicating that primarily the maturation of the protein is affected. Accordingly, when HIDS cell lines were cultured at 39 degrees C, MK activity decreased further. This triggered a compensatory increase in 3-hydroxy-3-methylglutaryl-CoA reductase activity, indicating that MK becomes progressively rate-limiting. A similar phenomenon occurs in vivo. MK activity in peripheral blood mononuclear cells drops 2-8-fold when HIDS patients experience febrile attacks. Our results suggest that minor elevations in temperature can set off a chain of events with MK becoming progressively rate-limiting, leading to a temporary deficiency of isoprenoid end-products, which induces inflammation and fever.  相似文献   
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