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91.
It has been demonstrated that plasma from patients with fulminant hepatic failure (FHF) interferes extensively with cellular function. We placed primary human and primary porcine hepatocytes in a polyurethane foam (PUF)/spheroid culture system and compared the metabolic functions in the plasma of patients with FHF in a 24-h stationary culture to those in a monolayer culture. The PUF/spheroid culture system using primary human and primary porcine hepatocytes significantly decreased ammonia content during 28-day culture. Fisher's ratio significantly increased at culture days 3 and 7. Tauroursodeoxycholic acid significantly increased and glycochenodeoxycholic acid and taurochenodeoxycholic acid decreased in the FHF patients' plasma at culture day 3. During at least a 24-h culture in the FHF patients' plasma, metabolic functions of primary human and primary porcine hepatocytes were almost identical. The present results indicate that the PUF/spheroid culture system using primary human or primary porcine hepatocytes demonstrated more advantageous metabolic functions in the plasma from patients with FHF than the monolayer culture.  相似文献   
92.
1. It has been recognized that hormone replacement therapy (HRT) may have a beneficial effect on protection against cardiovascular diseases. Oestrone is the major component of conjugated equiline oestrogens, which are commonly used in HRT. The present study was performed in order to investigate the effects of oestrone on the membrane fluidity of erythrocytes by means of an electron paramagnetic resonance (EPR) and spin-labelling method. 2. In an in vitro study, oestrone significantly decreased the order parameter (S) for 5-nitroxide stearate (5-NS) and the peak height ratio (ho/h-1) for 16-nitroxide stearate (16-NS) obtained from EPR spectra of erythrocyte membranes. This finding indicated that oestrone may increase the membrane fluidity and improve the membrane microviscosity of erythrocytes. 3. The effect of oestrone was significantly potentiated by the nitric oxide (NO) donor s-nitroso-N-acetylpenicillamine and the cGMP analogue 8-bromo-cGMP. 4. In contrast, the change in membrane fluidity induced by oestrone was antagonized by the NO synthase inhibitors NG-nitro-l-arginine methyl ester and asymmetric dimethyl-l-arginine. 5. The results of the present study show that oestrone significantly increases membrane fluidity and improves the rigidity of cell membranes, which is partially mediated by a NO- and cGMP-dependent pathway. Furthermore, the data may be consistent with the hypothesis that oestrone could have a beneficial effect on the rheological behaviour of erythrocytes and have a crucial role in the regulation of the microcirculation.  相似文献   
93.
We examined whether slight oxidative stress and/or damage in cells could be amplified by subsequent ionizing irradiation and thus become detectable as obvious chromosomal damage. WIL2-NS cells, a human B lymphoblastoid cell line, were pretreated with an oxidant and then exposed to X-rays at 0.25 or 0.5 Gy. The chromosomal damage in the cells was evaluated by cytokinesis-block micronucleus (CBMN) assay. Pretreatment with a superoxide-generating system (hypoxanthine (HX)/xanthine oxidase (XO), 1 and 2 mU/ml of XO), tert-butyl hydroperoxide (t-BuOOH, 10 and 100 microM) or H2O2 (5 microM) alone did not induce significant chromosomal damage, but the oxidant-induced damage increased significantly with subsequent irradiation. The tested dose of these oxidants did not induce significant changes in cell viability, the nuclear division index, and the concentration of antioxidants, indicating that only weak oxidative stress was introduced into the cells. These results suggest that low-dose oxidant-induced chromosomal damage becomes detectable as obvious chromosomal damage with subsequent ionizing irradiation in vitro.  相似文献   
94.
95.
Thorombospondin-1 (TSP-1) is a 450 kDa extracellular matrix glycoprotein, with anti-angiogenic activity. We analyzed the relationship in TSP-1 expression and Microvessel count (MVC), and also clinical factors, using immunohistochemical methods for non-small cell cancer (NSCLC). Histopathologically, there was inverse correlation between TSP-1 expression and MVC for squamous cell carcinoma, but not for adenocarcinoma cases. Among 199 completely resected cases of NSCLC, the 5-year survival was 77.0% when the expression of TSP-1 was maintained and 55.1% when the expression were reduced, respectively (P=0.0046). When compared with TSP-1 expression in the high MVC subgroup, there was significantly shorter survival time when TSP-1 expression was reduced (P=0.0091), and no significant difference was seen for the low MVC subgroup. Multivariate analysis revealed that expression of TSP-1 is as a prognostic factor of NSCLC. Our present data suggest that TSP-1 might not be a direct anti-angiogenic factor and the TSP-1 expression is a prognostic indicator of NSCLC.  相似文献   
96.
DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) has a defensive role against alkylating agents associated with increased incidence of malignant tumors. The aim of the current study was to elucidate the significance of immunohistochemical expression of MGMT in squamous cell carcinoma (SCC) of the esophagus, with a special reference to the correlation of smoking. Immunohistostaining of MGMT was performed in the specimens collected from 100 patients with SCC of the esophagus. The relationship between the personal history of smoking and MGMT expression was examined and the value of Brinkman index was compared between patients with and without MGMT expression. Fifty-five SCCs (55.0%) had a positive response to MGMT inununostaining. The proportion of patients who had tumors with MGMT expression among patients with smoking habits was 62.0% (49 out of 79), which was significantly higher than that among patients without smoking habits (28.6%, 6 out of 21; P=0.005). The mean value of Brinkman index in patients who had tumors with MGMT expression (1189+/-604) was significantly higher than that in patients who had tumors without MGMT expression (871+/-656; P=0.020). Our results suggested that MGMT expression in esophageal SCC might be correlated with smoking habits of the patients.  相似文献   
97.
98.
Genetic polymorphism of the serotonin 5-HT(2A) receptor seems to be associated with therapeutic response to selective serotonin reuptake inhibitors (SSRIs). The present study investigated whether a novel -1438G/A polymorphism in the promoter region of the 5-HT(2A )receptor gene is associated with therapeutic response to fluvoxamine (an SSRI) in 66 Japanese patients with major depressive disorder. Fluvoxamine (50 to 200 mg) was administered twice daily for 6 weeks. Fifty-four patients completed this study. The genotype distribution and the allele frequencies showed no significant difference between responders and non-responders. The time-course of the Montgomery-Asberg Depression Rating Scale scores showed no significant difference among -1438G/G, -1438G/A, and -1438A/A genotype groups. The results demonstrated that the -1438G/A promoter polymorphism in the 5-HT(2A) receptor gene was unlikely to have a major role in therapeutic response to fluvoxamine in Japanese patients with major depressive disorder.  相似文献   
99.
We report here gastric metastasis from lung carcinoma in an 80-year-old man. His chief complaint was epigastric pain from metastases in the stomach. Although metastasis from primary carcinoma of the lung to the small intestine is more common than has been previously suspected, symptoms are rare. Such a metastasis may present as bowel perforation. To find cases of lung carcinoma metastasis to the gastrointestinal tract is clinically rare, and there have been few reports in the English literature. This report describes the gastrointestinal metastasis from lung carcinoma.  相似文献   
100.
Background: We have previously reported the clinical characterization of a case of juvenile multiple colorectal carcinoma with hypogammaglobulinemia. Several recent studies have determined that agammaglobulinemia was caused by the loss of Brutons tyrosine kinase (Btk) function. However, any genetic alterations associated with carcinoma formation in individuals with this immunodeficient disease have not been reported.Methods: DNA from eight carcinoma tissues and nine adenoma tissues from this reported case were examined for mutations in p53 by single strand conformation polymorphism analysis, K-ras by mutant allele specific analysis, and replication error or loss of heterozygosity of the TP53 locus on chromosome #17.Results: We found that p53 and K-ras were mutated in the carcinoma tissues. However, each tumor showed unequal and diverse results.Conclusions: The progression of individual tumor was not due to a common genetic event caused directly under the influence of the primary disease at the genetic level.  相似文献   
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