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991.
Hepatocellular necrosis may be complicated in the clinical course of T-cell lymphoma. Herein are reported two cases of peripheral T-cell lymphoma associated with a rapid increase of serum transaminases in their final course. The final diagnoses were enteropathy-type T-cell lymphoma of the jejunum (patient 1) and hepatosplenic T-cell lymphoma (patient 2). The livers of both patients had non-zonal, well-demarcated coagulation necrosis (approximately 70% in patient 1 and 40% in patient 2) that was infiltrated by lymphoma cells bearing a cytolytic granule content (granzyme B). Hepatocytes in the necrotic areas in patient 2 showed immunoreactivity for human simplex virus type 1. Although the mechanism of the hepatocyte necrosis is unclear, it is suggested that the hepatocyte submassive necrosis may be related to an infection complicated in the final course of lymphoma or by certain direct effects of the tumor cells.  相似文献   
992.
Genomic sequencing was used to characterize most of the coding regions of the five two-domain stimulatory killer cell immunoglobulin-like receptor (KIR) loci from 80 unrelated, primarily Caucasian, individuals. Specific loci were present in from 26% (KIR2DS3) to 98% (KIR2DS4) of individuals. The number of known alleles present varied from one (KIR2DS1, KIR2DS5) to five (KIR2DS4). The frequencies of loci and alleles were similar to observations made in populations of European and Asian ethnicities. New alleles were found at 2DS1 (*00202, *00302, *005, *006, *007) and 2DS4 (*008) loci.  相似文献   
993.
The administration of beta-glucan (sonifilan; SPG) in combination with a non-steroidal anti-inflammatory drug, indomethacin (IND), induced lethal septic shock in mice. To demonstrate the influence of bacterial lipopolysaccharide (LPS) in this lethal toxicity, LPS non-responder C3H/HeJ mice were used to compare features of sepsis and physicochemical parameters in the present study. The administration of SPG and IND induced the death of C3H/HeJ mice, lowering rectal temperature, reducing body weight, increasing serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels, shortening the gastrointestinal tract, and increasing the GOT/GPT level. Microbial translocation to various organs was also significantly increased. These results strongly suggested that LPS-non-responding strain also induced septic shock in this experimental model, and other pathogen-associated molecular patterns (PAMPs) may significantly contribute to the septic shock.  相似文献   
994.
During 2000-2007, 218 influenza viruses of 28 different combinations of HA (H1-H13) and NA (N1-N9) subtypes were isolated from fecal samples of free-flying water birds at two distant lakes in Hokkaido, Japan. Phylogenic analysis of the matrix (M) genes of 67 strains, selected on the basis of their subtype combinations, revealed that A/duck/Hokkaido/W95/2006 (H10N8) was a reassortant whose M gene belonged to North American non-gull-avian and the other seven genes to Eurasian non-gull-avian lineages. The M genes of other 65 strains belonged to Eurasian non-gull-avian and the one to Eurasian-gull lineages. The M genes of 65 strains were grouped into three different sublineages, indicating that influenza viruses circulating in different populations of free-flying water birds have evolved independently in nature.  相似文献   
995.
Plexin-A4 negatively regulates T lymphocyte responses   总被引:3,自引:0,他引:3  
Semaphorins and their receptors play crucial roles not only in axon guidance during neuronal development but also in the regulation of immune responses. Plexin-A4, a member of the plexin-A subfamily, forms a receptor complex with neuropilins and transduces signals for class III semaphorins in the nervous system. Although plexin-A4 is also expressed in the lymphoid tissues, the involvement of plexin-A4 in immune responses remains unknown. To explore the role of plexin-A4 in the immune system, we analyzed immune responses in plexin-A4-deficient (plexin-A4-/-) mice. Among immune cells, plexin-A4 mRNA was detected in T cells, dendritic cells and macrophages but not in B cells and NK cells. Plexin-A4-/- mice had normal numbers and cell surface markers for each lymphocyte subset, suggesting that plexin-A4 is not essential for lymphocyte development. However, plexin-A4-/- mice exhibited enhanced antigen-specific T cell responses and heightened sensitivity to experimental autoimmune encephalomyelitis. Plexin-A4-/- T cells exhibited hyperproliferative responses to anti-CD3 stimulation and to allogeneic dendritic cells in vitro. Furthermore, this hyperproliferation was also observed in both T cells from neuropilin-1 mutant (npn-1(Sema-)) mice, in which the binding site of class III semaphorins is disrupted, and T cells from Sema3A-deficient (Sema-3A-/-) mice. Collectively, these results suggest that plexin-A4, as a component of the receptor complex for class III semaphorins, negatively regulates T cell-mediated immune responses.  相似文献   
996.
Fabry disease is an X-linked recessive inborn metabolic disorder caused by a deficiency of the lysosomal enzyme alpha-galactosidase A (EC 3.2.1.22). The causative mutations are diverse, include both large rearrangements and single-base substitutions, and are dispersed throughout the 7 exons of the alpha-galactosidase A gene (GLA). Mutation hotspots for Fabry disease do not exist. We examined 62 Fabry patients in Japan and found 24 GLA mutations, including 11 novel ones. A potential treatment reported for Fabry disease is active site specific chaperone (ASSC) therapy using 1-deoxygalactonojirimycin (DGJ), an inhibitor of alpha-galactosidase A, at subinhibitory concentrations. We transfected COS-7 cells with the 24 mutant GLAs and analyzed the alpha-galactosidase A activities. We then treated the transfected COS-7 cells with DGJ and analyzed its effect on the mutant enzyme activities. The activity of 11 missense mutants increased significantly with DGJ. Although ASSC therapy is useful only for misfolding mutants and therefore not applicable to all cases, it may be useful for treating many Japanese patients with Fabry disease.  相似文献   
997.
Neural stem cells (NSCs) have attracted considerable attention as a potential source of cells for therapeutic treatment of impaired areas of the central nervous system. However, efficient and clinically feasible strategies for expansion of the endogenous NSC pool are currently unavailable. In this study, we demonstrate that mood stabilizing drugs, which are used to treat patients with bipolar disorder, enhance the self-renewal capability of mouse NSCs in vitro and that this enhancement is achieved at therapeutically relevant concentrations in the cerebrospinal fluid. The pharmacological effects are mediated by the activation of Notch signaling in the NSC. Treatment with mood stabilizers increased an active form of Notch receptor and upregulated its target genes in neural stem/progenitor cells, whereas coculture with gamma-secretase inhibitor or the presence of mutation in the presenilin1 gene blocked the effects of mood stabilizers. In addition, chronic administration of mood stabilizers expanded the NSC pool in the adult brain, which subsequently increased the cell supply to the olfactory bulb. We suggest that treatment with mood stabilizing drugs could be used to facilitate regeneration following insult to the central nervous system.  相似文献   
998.
The C-857T promoter polymorphism of TNF-α gene is associated with obese type 2 diabetes, while the adiponectin G+276T gene polymorphism in intron 2 may influence the fat accumulation in the liver. In this study, we examined effects of these polymorphisms on clinical markers of insulin resistance and fatty liver (a liver/spleen CT ratio < 0.9). These polymorphisms were determined in 342 Japanese subjects with type 2 diabetes. The liver/spleen CT ratio was lower in the subjects with the adiponectin +276G/G genotype than that in the subjects with the +276T allele (P < 0.05), indicating that fat accumulation in the liver is associated with the +276G/G genotype. Multiple comparisons among the 4 combinations of each polymorphism of the TNF-α and adiponectin genes revealed a significant difference in the liver/spleen CT ratio (P < 0.05) among the 4 groups, indicating that the gene combinations influence the degree of fat accumulation in the liver. The subjects carrying the TNF-α -857T allele (C/T or T/T genotype) and the adiponectin +276G/G genotype had greater risks for fatty liver and insulin resistance that was evaluated by higher levels of fasting insulin and homeostasis model assessment of insulin resistance, as compared with the other groups. Therefore, Japanese subjects with the TNF-α -857T allele and the adiponectin +276G/G genotype may be more susceptible to insulin resistance and fatty liver. The present study provides the evidence for the interaction between TNF-α and adiponectin genes in the insulin resistance and fatty liver in Japanese subjects with type 2 diabetes.  相似文献   
999.
Recently, the heat stroke in the elderly who often remains at home during the day increases due to high temperatures in summer by urban heat island effect. We have examined how the elderly were influenced by the high summer temperatures. We explained the patients or the caregivers at home while showing the checklist of six items. In addition, we checked and interviewed time of visits, patients' room temperature, with or without air conditioning fan etc., and filled out their histories of summer heat. If some items of the checklist were not improved, we explained the care points again every time we visited. 10 people out of the 72 patients were identified as summer heat illness at home. We need to work together with medical cares and welfare services and the other organizations of each region.  相似文献   
1000.
Distinction of renal oncocytoma (RO) from chromophobe renal cell carcinoma (ChRCC) is important because their clinical behavior is different. As part of a search for the best available immunohistochemical markers to distinguish ChRCC from RO, we investigated the immunohistochemical profiles of these tumors. We selected 30 renal tumors consisting of ChRCC, typical variant (n = 14), ChRCC, eosinophilic variant (n = 6), and RO (n = 10). Their expression of cytokeratin (CK) 7, KAI1, epithelial-specific antigen (ESA), epithelial-related antigen (ERA), Claudin- 7, and Claudin-8 was studied using an autostainer. Immunoreactivity was assessed based on a combined score of the extent and intensity of staining. Compared to RO, a significantly higher percentage of the total ChRCCs stained positive for CK7 (85% vs. 10%, respectively), KAI1 (90% vs. 10%), ESA (95% vs. 10%), ERA (95% vs. 10%), and Claudin-7 (95% vs. 20%) (P < 0.001). Additionally, there was a significant difference between the percentage of ChRCC eosinophilic variant (ChRCC-E) and RO that stained positive for KAI1 (100% vs. 10%, respectively), ESA (83% vs. 10%), and ERA (83% vs. 10%) (P < 0.001). We recommend immunohistochemical analysis of KAI1, ESA, and ERA to distinguish ChRCC-E from RO.  相似文献   
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