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排序方式: 共有1079条查询结果,搜索用时 11 毫秒
1.
Effect of rufloxacin on in-vitro proliferation and differentiation of human mononuclear cells. 总被引:1,自引:0,他引:1
We investigated the effects of rufloxacin, a new, long acting fluoroquinolone, on the growth and differentiation of human peripheral blood mononuclear cells (MNC) stimulated with T- and B-cell mitogenic agents. Rufloxacin inhibited 3H-thymidine incorporation into MNC stimulated with phytohaemagglutinin (PHA) and pokeweed mitogen (PWM) in a dose-dependent manner. The concentrations of rufloxacin required to inhibit 1/2 maximal proliferation of T- and B-cells were 62 and 33.5 mg/L respectively. Rufloxacin, at clinically achievable serum levels (less than 10 mg/L), was found not to inhibit PHA-induced T-cell differentiation as assessed by IL-2 production, IL-2 receptor expression and the expression of cell differentiation markers (CD4 and CD8). However, higher concentrations of rufloxacin (10 and 50 mg/L) markedly inhibited B-cell differentiation in-vitro as determined by the measurement of immunoglobulin production by MNC stimulated with PWM. The clinical relevance of our in-vitro findings remains to be elucidated. 相似文献
2.
Dharmarajan Sriram Narasimharaghavan Srichakravarthy Tanushree R Bal Perumal Yogeeswari 《Biomedicine & Pharmacotherapy》2005,59(8):456-459
A series of nevirapine derivatives has been synthesized in an effort to enhance the spectrum of chemotherapeutic properties for the effective treatment of AIDS and AIDS-related opportunistic infections. The nevirapine derivative bearing isoniazid moiety (3a) was found to be the most potent compound with EC50 of<0.0636 microM, CC50 of>1000 microM and selectivity index of>15,723 which also exhibited 90% inhibition against Mycobacterium tuberculosis at 6.25 microg/ml. Compound 3c showed 100% inhibition against M. tuberculosis and also exhibited potent antibacterial activity against 24 pathogenic bacteria with MIC less than 1 microg/ml. 相似文献
3.
The pulmonary flow pattern was analysed by pulsed Doppler in 77 normal neonates, at < 48 hours (36 subjects), 49 to 96 hours (25 subjects) and 97 to 148 hours (16 subjects). From the flow velocity spectrum, using an built in computer system, the acceleration time and the ejection time were measured, and the ratio was calculated. This ratio was 0.24 +/- 0.08 in the subjects within 48 hours whereas this ratio was 0.53 +/- 0.11 in the subjects above 97 hours; thus the ratio increased with age. We noticed that the ratio obtained from the pulsed Doppler is useful in assessing the pulmonary vascular status, even in neonates. 相似文献
4.
Hagood JS Prabhakaran P Kumbla P Salazar L MacEwen MW Barker TH Ortiz LA Schoeb T Siegal GP Alexander CB Pardo A Selman M 《The American journal of pathology》2005,167(2):365-379
Fibroblasts consist of heterogeneous subpopulations that have distinct roles in fibrotic responses. Previously we reported enhanced proliferation in response to fibrogenic growth factors and selective activation of latent transforming growth factor (TGF)-beta in fibroblasts lacking cell surface expression of Thy-1 glycoprotein, suggesting that Thy-1 modulates the fibrogenic potential of fibroblasts. Here we report that compared to controls Thy-1-/- C57BL/6 mice displayed more severe histopathological lung fibrosis, greater accumulation of lung collagen, and increased TGF-beta activation in the lungs 14 days after intratracheal bleomycin. The majority of cells demonstrating TGF-beta activation and myofibroblast differentiation in bleomycin-induced lesions were Thy-1-negative. Histological sections from patients with idiopathic pulmonary fibrosis demonstrated absent Thy-1 staining within fibroblastic foci. Normal lung fibroblasts, in both mice and humans, were predominantly Thy-1-positive. The fibrogenic cytokines interleukin-1 and tumor necrosis factor-alpha induced loss of fibroblast Thy-1 surface expression in vitro, which was associated with Thy-1 shedding, Smad phosphorylation, and myofibroblast differentiation. These results suggest that fibrogenic injury promotes loss of lung fibroblast Thy-1 expression, resulting in enhanced fibrogenesis. 相似文献
5.
Sulfatide, ceramide galactosyl-3'-sulfate, is mainly present in nervous tissue, kidney, testis, red blood cells, platelets and granulocyte. Antibodies to sulfatide are present in many patients with demyelinating peripheral neuropathy, HIV infection and systemic lupus erythematosus and may account for some of the clinical manifestations. To evaluate the effect of such antibodies, we have constructed a phage-display antibody fragment library from the lymphocytes of patients with systemic lupus erythematosus. Sulfatide-reactive phage were selected by absorption and elution on sulfatide liposomes and soluble single chain variable fragment (ScFv) were isolated from individual colonies and tested in an ELISA assay for binding to bovine brain sulfatide. Five ScFv clones that bound sulfatide were isolated. Two of the clones, PH5 and PA38, bound sulfatide but not phosphatidylserine, phosphatidylcholine, phosphatidylethanolamine, sphingomyelin or ceramide. These two clones also bound sulfatide from human red blood cells. The DNA encoding the fragments was sequenced, revealing predicted polypeptides of 19 kDa for PH5 containing only variable heavy (VH) sequences, and 31 kDa for PA38, with both VH and variable light (VL) sequences. Although they had similar antigen specificities, the VH domains of the two clones were derived from different heavy-chain families. The clustered mutational patterns in the complementarity-determining region (CDR) of the heavy chains in both clones suggest that the V-domains are the products of antigen-driven B cell clonal maturation leading to the development of sulfatide-binding specificity. These results show the presence of sulfatide-specific antibodies in lupus patients, and allow us to test the possibility that the interaction of the antibodies with sulfatide may contribute to some of the symptoms. In addition, the antibodies provide useful reagents to test the role of sulfatide in pathophysiological processes. 相似文献
6.
7.
Klein SM Slaughter TF Vail PT Ginsberg B El-Moalem HE Alexander R D'Ercole F Greengrass RA Perumal TT Welsby I Gan TJ 《Anesthesia and analgesia》2000,91(5):1091-1095
Low molecular weight heparin (LMWH) is commonly used to prevent postoperative thromboembolism. Currently, there is no convenient test to measure the degree of anticoagulation from LMWH. This prospective study examines the relationship of thromboelastography and serum anti-Xa concentration in patients treated with enoxaparin. Twenty-four adult patients scheduled for orthopedic surgery using epidural anesthesia were enrolled. Epidural catheters were removed the morning after surgery before the commencement of subcutaneous enoxaparin 30 mg twice daily. Venous blood samples were obtained at 1) the induction of anesthesia (baseline), 2) immediately before the third dose of enoxaparin postoperatively (Day 2-trough), 3) 4 h after the third dose postoperatively (Day 2-peak), and 4) immediately before the fifth dose postoperatively (Day 3-trough). Whole blood samples were obtained for thromboelastography, activated clotting time, and anti-Xa level analyses at each of the four time intervals. At the four sample intervals, the r time (mean +/- SEM). (20 +/- 1, 25 +/- 2, 51 +/- 6, 31 +/- 3 mm) and the k time (9 +/- 0. 7, 12 +/- 1, 27 +/- 5, 14 +/- 2 mm) of the thromboelastograph were significantly correlated with the expected peak and trough levels of LMWH and serum anti-Xa levels (P: < 0.05). At the Day 3-trough, thromboelastograph r times exceeded the normal range in 6 of 25 patients (25%). Prolongation of r time and k time on postoperative Day 3 may indicate an exaggerated response to LMWH. Thromboelastography is a test that could potentially correlate with the degree of anticoagulation produced by low molecular weight heparin. Implications: Thromboelastography is a test that could potentially correlate with the degree of anticoagulation produced by low molecular weight heparin. The r time from the thromboelastogram correlates with serum anti-Xa concentration. 相似文献
8.
9.
Prabhakaran Rema Somanathan Thara Ramani Wesley 《International journal of gynaecology and obstetrics》2008,103(2):105-110
Objective
To evaluate the effectiveness and safety of the loop electrosurgical excision procedure (LEEP) to treat cervical intraepithelial neoplasia (CIN) in a low-resource setting.Methods
Women participating in a cervical screening study in India with histologically confirmed CIN unsuitable for cryotherapy were advised to undergo LEEP. One year after treatment the cervix was visually inspected with acetic acid, followed by colposcopy and biopsy taken from abnormal areas. Cure was defined as no clinical or histologic evidence of CIN. Factors influencing cure rates were evaluated by χ2 tests.Results
Of the 311 women who underwent LEEP, 283 reported for 1-year follow-up and 248 (87.6%) were disease free. Cure rates were 93.0% for CIN 1, 85.5% for CIN 2, and 72.7% for CIN 3. Minor adverse effects were observed in 34 women and complications were seen in 5 women.Conclusion
LEEP was associated with minimal complications and acceptable cure rates in a low-resource setting, although women with larger lesions had lower cure rates. 相似文献10.
Vettriselvi V Vijayalakshmi K Paul SF Venkatachalam P 《The journal of obstetrics and gynaecology research》2008,34(3):301-306
AIM: To assess the association between polymorphisms in angiotensin converting enzyme and methylene tetrahydrofolate reductase genes and recurrent pregnancy loss by a case-control study in South Indian women. METHODS: DNA was extracted from peripheral blood leukocytes of 104 women with Recurrent Pregnancy Loss (RPL) and 120 controls. Genotyping of ACE Insertion Deletion and MTHFR C677T polymorphism were carried out by PCR and PCR-RFLP, respectively. RESULTS: No statistically significant difference was observed in the distribution of genotypes between cases and controls for ACE and MTHFR polymorphisms. Further, the combination of MTHFR and ACE genotypes failed to reveal an association. CONCLUSION: In conclusion, the present study reveals lack of association of MTHFR C677T and ACE I/D polymorphisms in RPL in South Indian women. However, we cannot exclude the possibility that other polymorphisms of ACE and MTHFR genes could be associated with the disease and might be clinically useful as a marker to assess risk for RPL. 相似文献