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51.
The TRPA1 channel has been proposed to be a molecular transducer of cold and inflammatory nociceptive signals. It is expressed on a subset of small primary afferent neurons both in the peripheral terminals, where it serves as a sensor, and on the central nerve endings in the dorsal horn. The substantia gelatinosa (SG) of the spinal cord is a key site for integration of noxious inputs. The SG neurons are morphologically and functionally heterogeneous and the precise synaptic circuits of the SG are poorly understood. We examined how activation of TRPA1 channels affects synaptic transmission onto SG neurons using whole‐cell patch‐clamp recordings and morphological analyses in adult rat spinal cord slices. Cinnamaldehyde (TRPA1 agonist) elicited a barrage of excitatory postsynaptic currents (EPSCs) in a subset of the SG neurons that responded to allyl isothiocyanate (less specific TRPA1 agonist) and capsaicin (TRPV1 agonist). Cinnamaldehyde evoked EPSCs in vertical and radial but not islet or central SG cells. Notably, cinnamaldehyde produced no change in inhibitory postsynaptic currents and nor did it produce direct postsynaptic effects. In the presence of tetrodotoxin, cinnamaldehyde increased the frequency but not amplitude of miniature EPSCs. Intriguingly, cinnamaldehyde had a selective inhibitory action on monosynaptic C‐ (but not Aδ‐) fiber‐evoked EPSCs. These results indicate that activation of spinal TRPA1 presynaptically facilitates miniature excitatory synaptic transmission from primary afferents onto vertical and radial cells to initiate action potentials. The presence of TRPA1 channels on the central terminals raises the possibility of bidirectional modulatory action in morphologically identified subclasses of SG neurons.  相似文献   
52.
Cancer stem cells are thought to be closely related to tumor progression and recurrence, making them attractive therapeutic targets. Stem cells of various tissues exist within niches maintaining their stemness. Glioblastoma stem cells (GSCs) are located at tumor capillaries and the perivascular niche, which are considered to have an important role in maintaining GSCs. There were some extracellular matrices (ECM) on the perivascular connective tissue, including type 1 collagen. We here evaluated whether type 1 collagen has a potential niche for GSCs. Imunohistochemical staining of type 1 collagen and CD133, one of the GSCs markers, on glioblastoma (GBM) tissues showed CD133‐positive cells were located in immediate proximity to type 1 collagen around tumor vessels. We cultured human GBM cell lines, U87MG and GBM cells obtained from fresh surgical tissues, T472 and T555, with serum‐containing medium (SCM) or serum‐free medium with some growth factors (SFM) and in non‐coated (Non‐coat) or type 1 collagen‐coated plates (Col). The RNA expression levels of CD133 and Nestin as stem cell markers in each condition were examined. The Col condition not only with SFM but SCM made GBM cells more enhanced in RNA expression of CD133, compared to Non‐coat/SCM. Semi‐quantitative measurement of CD133‐positive cells by immunocytochemistry showed a statistically significant increase of CD133‐positive cells in Col/SFM. In addition, T472 cell line cultured in the Col/SFM had capabilities of sphere formation and tumorigenesis. Type 1 collagen was found in the perivascular area and showed a possibility to maintain GSCs. These findings suggest that type 1 collagen could be one important niche component for CD133‐positive GSCs and maintain GSCs in adherent culture.  相似文献   
53.
PURPOSE: The aim of this study was to clarify genetic and epigenetic alterations occurring during renal carcinogenesis. EXPERIMENTAL DESIGN: Copy number alterations were examined by array-based comparative genomic hybridization analysis using an array harboring 4,361 bacterial artificial chromosome clones, and DNA methylation alterations on CpG islands of the p16, human MutL homologue 1, von Hippel-Lindau, and thrombospondin 1 genes and the methylated in tumor (MINT-1, MINT-2, MINT-12, MINT-25, and MINT-31) clones were examined in 51 clear cell renal cell carcinomas (RCC). RESULTS: By unsupervised hierarchical clustering analysis based on copy number alterations, clear cell RCCs were clustered into the two subclasses, clusters A (n=34) and B (n=17). Copy number alterations were accumulated in cluster B. Loss of chromosome 3p and gain of 5q and 7 were frequent in both clusters A and B, whereas loss of 1p, 4, 9, 13q, and 14q was frequent only in cluster B. The average number of methylated CpG islands in cluster B was significantly higher than those in cluster A. Clear cell RCCs showing higher histologic grades, vascular involvement, renal vein tumor thrombi, and higher pathologic stages were accumulated in cluster B. The recurrence-free and overall survival rates of patients in cluster B were significantly lower than those of patients in cluster A. Multivariate analysis revealed that genetic clustering was a predictor of recurrence-free survival and was independent of histologic grade and pathologic stage. CONCLUSIONS: This genetic clustering of clear cell RCC is significantly associated with regional DNA hypermethylation and may become a prognostic indicator for patients with RCC.  相似文献   
54.
In the present investigation we studied the morphology o the endolymphatic sac in guinea pig fetuses (age 20-, 30-, 45-, 60-days-old and newborns). Twenty-day and 30-days-old guinea pig fetuses often displayed small prismatic or hexagonally shaped granules, presumably representing miniature otoconia. The granules appeared freely in the lumen of the endolymphatic sac as well as incorporated in the cytoplasm of the freely floating cells or macrophages. The origin of these "sac otoconia' as well as the possible role of the endolymphatic sac in statoconis turnover and metabolism is discussed.  相似文献   
55.
This paper reviews the results of basic research conducted by the author's group to determine appropriate methods to develop protein-based drugs. These include production strategies, elucidation of physiologic function, improving existing pharmaceuticals, de novo design, and protein reconstruction. The antigenicity of modified proteins and methods to induce antigenic protein tolerance are also described.  相似文献   
56.
57.
Beta-amyloid peptide 1-42 is a major peptide constituent of beta-amyloid fibrils. We investigated the role of sucrose on the deposition and the D-aspartic acid formation in an amyloidogenic peptide 1-42 under physiological conditions. From analyses using thioflavine-T fluorometric assay and electronmicroscopic spectroscopy after 60 h incubation at 37 degrees C, it was found that sucrose retarded the fibril formation in the amyloidogenic peptide. The retardation of the formation of amyloid fibrils by sucrose was suggested to be not due to viscosity but due to disturbance of the assemlby of alpha-helix containing peptides. Moreover, we showed that the formation of D-aspartyl residue, which is found in beta-amyloid fibrils from Alzheimer disease brains, in the amyloidogenic peptide was also retarded in the presence of sucrose.  相似文献   
58.
59.
BACKGROUND: To the authors' knowledge, there had been no evidence for the efficacy of psychosocial intervention among Japanese cancer patients. The objective of this study was to determine the effect of a psychosocial group intervention in reducing psychologic distress and enhancing coping in this population in a randomized controlled trial. METHODS: The patient selection criteria were age younger than 65 years, lymph node metastasis positive and/or histologic or nuclear Grade 2-3, and surgery undergone within the previous 4-18 months as of the start of the study. We conducted a 6-week, structured, psychosocial group intervention. The intervention consisted of health education, coping skills training, stress management, and psychologic support. Subjects were assessed for psychologic distress and coping by administering the Profile of Mood States (POMS), Mental Adjustment to Cancer (MAC) scale, and Hospital Anxiety and Depression (HADS) scale at the baseline, at 6 weeks, and at 6 months. RESULTS: Fifty (33%) of the 151 patients participated and were randomized, and 46 (30%) completed the study. The experimental group had significantly lower scores than the controls for total mood disturbance and significantly higher scores for vigor on the POMS, and significantly higher scores for fighting spirit on the MAC at the end of the 6-week intervention. These improvements were sustained over 6 months of follow-up. CONCLUSIONS: The results of this study suggest that a short term psychosocial group intervention produces significant long term improvement in the quality of life of Japanese patients with primary breast carcinoma.  相似文献   
60.
We studied the nature of IgM-like protein responsible for non-specific reactive phenomena occurred occasionally in EIA determination of CA125. We isolated highly purified IgM-like protein from two patients with non-specifically high CA125 serum values in affinity high performance liquid chromatography (HPLC) using anti-human IgM antibody-TSKgel Tresy15PW column. The isolated IgM-like protein possessed CA125 activity determined in EIA method. SDS-PAGE profiles of this isolated IgM-like protein were compatible with that of normal human IgM, and were distinct from those of CA125 antigen. Moreover, we ruled out the possibility that the Fc region of anti-CA125 monoclonal antibody might be responsible for the non-specific reactive phenomena. Thus, the data obtained from the present study indicate that the IgM-like protein is an anti-idiotypic antibody against the anti-CA125 monoclonal antibody (OC125).  相似文献   
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