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991.
992.
Dysregulated NOTCH1 signaling, by either gene mutations or microenvironment interactions, has been increasingly linked to chronic lymphocytic leukemia (CLL). Thus, inhibiting NOTCH1 activity represents a potential therapeutic opportunity for this disease. Using gene expression‐based screening, we identified the calcium channel modulator bepridil as a new NOTCH1 pathway inhibitor. In primary CLL cells, bepridil induced selective apoptosis even in the presence of the protective stroma. Cytotoxic effects of bepridil were independent of NOTCH1 mutation and other prognostic markers. The antitumor efficacy of bepridil was associated with inhibition of NOTCH1 activity through a decrement in trans‐membrane and activated NOTCH1 protein levels with unchanged NOTCH2 protein levels. In a CLL xenotransplant model, bepridil significantly reduced the percentage of leukemic cells infiltrating the spleen via enhanced apoptosis and decreased NOTCH1 activation. In conclusion, we report in vitro and in vivo anti‐leukemic activity of bepridil associated with inhibition of the NOTCH1 pathway in CLL. These data provide a rationale for the clinical development of bepridil as anti‐NOTCH1 targeted therapy for CLL patients.  相似文献   
993.
BACKGROUND: The prognosis for many children with cow's milk allergy (CMA) is remission within 3 years, and the clinical parameters that predict duration of disease have not been measured incrementally. OBJECTIVE: To prospectively determine prognostic predictors of tolerance in a random cohort of referrals using CMA workup outcomes as covariates and tolerance as the status variable in a duration model of CMA. METHODS: The 2001-2006 Milan Cow's Milk Allergy Cohort (MiCMAC) enrolled children referrals using double-blind, placebo-controlled food challenges (DBPCFCs) as study end points (confirmation of CMA; onset of tolerance). The Cox regression model was used to analyze all clinical factors that contributed to tolerance. Covariates analyzed were skin, gastrointestinal, and respiratory symptoms; history and demographics at presentation; age at diagnosis and DBPCFC outcomes; sensitization (skin and serum) by cow's milk protein fractions; sensitization to other food and inhalant allergens; total IgE levels; specific IgE concentrations for cow's milk protein fractions, other ingestants, and aeroallergens; and threshold doses at DBPCFC. Sensitization and DBPCFC were performed at 6-month intervals. RESULTS: A total of 112 infants were enrolled (mean [SD] age, 13.85 [9.84] months), and 59 achieved tolerance (mean [SD] age when tolerance was achieved, 27.58 [11.81] months). On univariate analysis, asthma and/or rhinitis at presentation was an independent predictor of persistence (hazard ratio [HR], 2.19; 95% confidence interval [CI], 1.26-3.82). On multivariate analysis, predictors of persistence were a fresh milk wheal diameter increment of 1 mm (HR, 1.18; 95% CI, 1.07-1.31) and a positive skin prick test result with soy (HR, 6.99; 95% CI, 1.56-31.25). CONCLUSIONS: This is the first study, to our knowledge, to identify incremental biological predictors of delayed tolerance to cow's milk in children that should be integrated into DBPCFC schedules for CMA in infants.  相似文献   
994.
Clinical heterogeneity for Sanfilippo B syndrome (MPS III B) in the same family has never been reported previously. We describe two clinically severe cases and one clinically mild case of MPS III B in a Neapolitan sibship. We could not detect N-acetyl-alpha-D-glucosaminidase activity in the sera of either the severe or mild cases. Mucopolysacchariduria mainly due to heparan sulfate excretion was consistently high in the severely affected patients and extremely variable in the mildly affected one.  相似文献   
995.
Summary The occurrence and the distribution of cytokeratin (CK)-immunoreactive reticulum cells in a series of normal and pathological human lymph nodes and spleens are documented. The immunoreactive cells exhibit morphological and immunophenotypic features of so-called fibroblastic reticulum cells, with or without myoid differentiation. They invariably co-express vimentin and, to a lesser extent, desmin and muscle-specific actin isoforms. These CK-immunoreactive cells are apparently a normal subpopulation of reticulum cells, being detectable from the early stages of spleen and lymph node development. They are distributed mainly in the paracortical and medullary regions of the lymph nodes and at the periphery of the white pulp in the spleen. Their number and distribution are highly variable in different neoplastic and non-neoplastic pathological conditions but the changes are not disease specific. CK-immunoreactive reticulum cells are easily identifiable in both frozen and fixed lymphoid tissue and in cytological smears of fine-needle aspirates, provided that monoclonal antibodies whose spectrum of reactivity includes cytokeratins 8 and 18 are used. The awareness of the occurrence of CK-immunoreactive cells in normal lymphoid tissues is of particular relevance in the search for micrometastatic foci using anti-CK antibodies.  相似文献   
996.
OBJECTIVES: Previous studies indicate that low-dose hormone replacement therapy (LD-HRT) can relieve vasomotor symptoms and prevent spine bone loss. METHODS: In the present study, we evaluated the effects of a low dose of conjugated equine estrogens (CEE; 0.3 mg) associated with different progestins in continuous combined scheme [2.5 mg of medroxyprogesterone acetate (n=25), 5 mg dydrogesterone (n=27), 2.5 mg nomegestrol (n=11)] as single group, on femur bone mineral density (BMD) and bone metabolism in young postmenopausal women (相似文献   
997.
Gill and air sac of the Indian catfish Heteropneustes fossilis harbour a nerve network comprising an innervated system of neuroepithelial endocrine cells; the latter cells are found especially in the gill. A series of antibodies was used for the immunohistochemical detection of neurotransmitters of the neural non-adrenergic, non-cholinergic (NANC) systems such as the sensory neuropeptides (enkephalins), the inhibitory neuropeptide VIP and neuronal nitric oxide synthase (nNOS) responsible for nitric oxide (NO) production which is an inhibitory NANC neurotransmitter. NADPH-diaphorase (NADPH-d) histochemistry was used as marker of nNOS although it is not a specific indicator of constitutively-expressed NOS in gill and air sac tissues. A tyrosine hydroxylase antibody was used to investigate adrenergic innervation. Nitrergic and VIP-positive sensory innervation was found to be shared by gill and air sac. Immunohistochemistry revealed the presence of enkephalins, VIP, NOS and NADPH-d in nerves associated with branchial and air sac vasculature, and in the neuroendocrine cell systems of the gill. Adrenergic nerve fibers were found in some parts of the air sac vasculature. The origin of the nerve fibers remains unclear despite previous findings showing the presence of both NADPH-d and nNOS in the sensory system of the glossopharyngeal and vagus nerves including the branchial structure. Scarce faintly stained nNOS-positive neurons were located in the gill but were never detected in the air sac. These findings lead to the conclusion that a postganglionic innervation of the airways is absent. Mucous goblet cells in the gill were found to express nNOS and those located in the non-respiratory interlamellar areas of the air sac were densely innervated by nNOS-positive and VIP-positive nerve fibers. Our immunohistochemical studies demonstrate that most arteries of the gill and air sac share a NANC (basically nitrergic) innervation which strongly suggests that they are homologous structures.  相似文献   
998.
Activating mutations in human fibroblast growth factor receptors (FGFR) result in a range of skeletal disorders, including craniosynostosis. Because the cranial bones are largely neural crest derived, the possibility arises that increased FGF signalling may predispose to premature/excessive skeletogenic differentiation in neural crest cells. To test this hypothesis, we expressed wild-type and mutant FGFRs in quail embryonic neural crest cells. Chondrogenesis was consistently induced when mutant FGFR1-K656E or FGFR2-C278F were electroporated in ovo into stage 8 quail premigratory neural crest, followed by in vitro culture without FGF2. Neural crest cells electroporated with wild-type FGFR1 or FGFR2 cDNAs exhibited no chondrogenic differentiation in culture. Cartilage differentiation was accompanied by expression of Sox9, Col2a1, and osteopontin. This closely resembled the response of nonelectroporated neural crest cells to FGF2 in vitro: 10 ng/ml induces chondrogenesis, Sox9, Col2a1, and osteopontin expression, whereas 1 ng/ml FGF2 enhances cell survival and Sox9 and Col2a1 expression, but never induces chondrogenesis or osteopontin expression. Transfection of neural crest cells with mutant FGFRs in vitro, after their emergence from the neural tube, in contrast, produced chondrogenesis at a very low frequency. Hence, mutant FGFRs can induce cartilage differentiation when electroporated into premigratory neural crest cells but this effect is drastically reduced if transfection is carried out after the onset of neural crest migration.  相似文献   
999.
In order to investigate the role of postnatal neurogenesis in granule cell number control in the rat dentate gyrus, we administered Methylazoxymethanol (MAM), a drug able to prevent cells from dividing, on P3, P5, P7, P9, when the most granule cells are produced. The effect of MAM on the number of proliferating precursors and of granule cells was examined at P16 and P90. We used 5-bromo-2'-deoxyuridine administration to label proliferating cells and immunohistochemistry to characterize the cell phenotype using neuron markers TUC 4, PSA-NCAM, Calbindin D28K and glial marker GFAP. At 16 days of age in MAM-treated rats we observed a significant decrease of BrdU-positive cells. Consistently, a decrease in density and number of granule cells was found compared to the controls. At 90 days the dentate gyrus of treated rats showed a complete recovery: no differences in the density, total number of neurons, the BrdU- and TUC 4-positive cells were revealed with respect to the controls. No deficits were evident in performance on the water maze in MAM-treated rats. These data suggest that the dentate gyrus is able to re-establish the proliferative zone and to rebuild the granule cell layer following neonatal MAM administration.  相似文献   
1000.
Functional roles of extracellular signal-related kinase (ERK) activation in dendritic-cell (DC) maturation have been unclear. In the present study, we investigated the ERK pathway in tumor necrosis factor (TNF)-alpha-induced maturation of murine spleen-derived DC. TNF-alpha increased surface expressions of major histocompatibility (MHC) and costimulatory molecules on DC in a dose-dependent manner. High (40 ng/ml) and low (0.4 ng/ml) concentrations of TNF-alpha markedly enhanced ERK1/2 activation in DC, and this activation was blocked completely by PD98059, a selective inhibitor of the ERK pathway. When DC were treated with TNF-alpha at a low but not a high concentration, PD98059 notably enhanced surface expressions of the MHC and costimulatory molecules and allostimulatory capability of the DC. Interleukin (IL)-12 production was enhanced significantly by PD98059 in DC treated with low or high concentration of TNF-alpha. These findings suggest that TNF-alpha-induced ERK activation negatively controls maturation and IL-12 production in murine DC.  相似文献   
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