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排序方式: 共有4877条查询结果,搜索用时 15 毫秒
81.
Shinozaki K Okamura T Nishio Y Kashiwagi A Kikkawa R Toda N 《European journal of pharmacology》2000,394(2-3):295-299
Mechanical responses to superoxide anion scavengers and nitric oxide (NO) synthase inhibitors in aortic endothelial cells were compared in normal chow-fed rats and those made insulin-resistant by feeding of fructose. Cu(2+), Zn(2+)-superoxide dismutase-induced vascular relaxation and superoxide production, measured by the lucigenin-enhanced chemiluminescence method, were greater in aortas from fructose-fed rats than in those from normal chow-fed rats. N(G)-nitro-L-arginine-induced contractions due to suppression of NO synthase activity were smaller in aortas from fructose-fed rats. Vascular mechanical responses may reflect the generation of superoxide and NO by the endothelium. Thus, isometric tension studies may be a useful tool for evaluating the production of these radicals in blood vessels. 相似文献
82.
Summary Levels of serum tumor markers including tissue polypeptide antigen (TPA), CA 15-3, CA 19-9, squamous cell carcinoma antigen, carcinoembryonic antigen, -fetoprotein, and PAP were measured in 26 patients with bone metastasis and in 9 patients with primary bone tumors. More than one markers was elevated in 19 of the 26 patients with bone metastasis, although there was no elevation of the markers in 3 patients with renal cell carcinoma. TPA was the most sensitive marker in the diagnosis of metastasis. CA 15-3 was also a sensitive marker in this study, since metastasis from breast carcinoma may be the most common of all metastases in the skeleton. On the other hand, -fetoprotein was uniformly unresponsive except in one case of gastric cancer. Combinations of markers are valuable for metastasis screening tests. No definite correlations were found between the markers in this study. On the other hand, there was a slight elevation of the markers observed in two of the nine patients with primary bone lesions. Serum tumor markers are useful in the diagnosis of bone metastasis to differentiate it from primary bone lesions. Especially in solitary bone lesions, serum markers may be the only way to make a differential diagnosis between the two. 相似文献
83.
Onishi T Nishikawa K Hasegawa Y Yamada Y Soga N Arima K Yamakado K Hoshina A Sugimura Y 《Japanese journal of clinical oncology》2007,37(10):750-754
OBJECTIVE: The purpose of this study was to assess the changes in health-related quality of life (HRQoL) during follow-up period in patients treated with percutaneous radiofrequency ablation (RFA) or laparoscopic surgery for small renal cell carcinoma. METHODS: From December 2004 through September 2006, for 37 consecutive patients, who were diagnosed with renal cell carcinoma and underwent percutaneous RFA (n = 20) or laparoscopic radical nephrectomy (n = 17) at our institution. HRQoL was evaluated prospectively using SF-36 Health survey pre- and post-operatively (1, 4, 12 and 24 weeks after surgery). RESULTS: Four of the eight scale scores of SF-36 were significantly lower pre-operatively in the RFA group than in the laparoscopic surgery group. The QoL scores in physical functioning, role-physical functioning and role-emotional functioning were significantly reduced one week after laparoscopic surgery. However, there was no reduction of the SF-36 QoL scores one week after operation in the RFA group. Furthermore, HRQoL scores in the RFA group showed a tendency to improve during follow-up periods. CONCLUSIONS: This is the first study to evaluate HRQoL changes (up to 24 weeks) in patients who have undergone RFA or laparoscopic radical nephrectomy for small renal cell carcinoma. No reduction, but rather an improvement, in HRQoL was seen in the RFA group during follow-up periods. From the point of view of QoL, RFA could be a viable alternative treatment for selected patients with small renal cell carcinoma. RFA could be a viable alternative treatment for the selected patients with small renal cell carcinoma. 相似文献
84.
85.
Yoshida K Miyashita N Obase Y Fukuda M Syoji H Yagi S Mohri K Kobashi Y Niki Y Oka M 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2006,80(6):701-705
We had reported that the rate of non-specific reaction in measurement of (1-->3)-beta-D-glucan was decreased by improvement of the alkaline pretreatment reagent of Fungitec G-test MK (MK assay). To compare the clinical usefulness between conventional MK assay and new MK assay using improved alkaline pretreatment reagent, 121 plasma samples were tested. The sensitivity, specificity, positive predictive value (PPV), negative predictive values (NPV) in conventional MK assay were 91.7%, 85.3%, 44.0% and 98.8%, respectively. Those in new MK assay were 75.0%, 91.6%, 52.9% and 96.7%, respectively. On the other hand, area under the curve (AUC) of receiver operating characteristic (ROC) analysis in conventional and new MK assay was 0.9175 and 0.9123 without a significant difference. It has been recognized that the sensitivity in conventional MK assay is higher than those in other beta-glucan assays. Then, the specificity of new MK assay was improved by using improved alkaline pretreatment reagent, without decreasing the sensitivity. Thus, the present findings indicate that the new MK assay is clinically quite useful. 相似文献
86.
87.
To compare nongenomic effects of progesterone on various receptor responses of neurons, Aplysia ganglion cells were pretreated with 30 microM progesterone for 5 min and various receptor responses were tested using a conventional voltage-clamp method. Progesterone reduced nicotinic receptor-activated Na(+)-currents, nicotinic receptor-activated Cl(-)-currents, gamma-aminobutyric acid receptor-activated Cl(-)-currents, and dopamine receptor-activated Na(+)-currents. These depressant effects are similar at two different agonist concentrations. On the other hand, progesterone affected neither muscarinic receptor-activated K(+)-currents nor dopamine receptor-activated K(+)-currents. The former four types of receptors are known to be ionotropic while the latter two types of receptors are known to be metabotropic. Therefore, progesterone selectively inhibited all the types of ionotropic receptor responses, presumably in a noncompetitive manner. 相似文献
88.
OBJECTIVES: The ultimate goal of this study is to improve the efficiency of gene transfer in mammalian muscle by developing targeted adenoviral vectors. Altering the tropism of viral vectors to recognize tissue specific antigens is one method to achieve this goal. This approach requires identification of cell-surface receptors and the insertion of target peptide sequences into the adenoviral fiber protein. In this study, phage biopanning was performed on cultured rat skeletal and laryngeal muscle to identify cell-surface receptors. STUDY DESIGN: In vitro cell culture and in vivo animal model. METHODS: M-13 Phage biopanning was used for muscle cell-surface receptor analysis on cultured rat skeletal and laryngeal muscle. Nonbinding and binding phage to cultured skeletal and laryngeal muscle were screened for muscle specific surface peptides. In vivo studies were then performed using muscle specific phage. RESULTS: Skeletal muscle specific binding by the YASTNPM phage was observed by in vivo immunostaining. Phage titering demonstrated a 10(9)-fold increase in skeletal muscle binding compared with nontarget tissue. A peptide sequence (NPSQVKH) specific for laryngeal muscle yielded a 10(7)-fold increase in laryngeal muscle phage titer compared with nontarget tissue. CONCLUSIONS: These results identify muscle cell-surface receptors that may be used as potential targets for genetic modification of adenovirus tropism. Moreover, phage specificity for skeletal and laryngeal muscle indicates specific muscle groups may be targeted. 相似文献
89.
Nagasawa S Yoshida T Terashima N Mizoguchi T Yagasaki H Kamijo K Ito M Platt JA Oshida Y 《Dental materials journal》2005,24(1):140-148
The thermal expansion rate, coefficient of thermal expansion, and high temperature strength of two types of commercially available alloy for metal-bond porcelain, KIK-HII (KIK) and Degubond-J2 (J2), were evaluated up to the liquidus point temperature using a thermo-mechanical analyzer. Furthermore, microstructure in the solid-liquid coexisting region was observed for evaluation. Our results revealed the following findings: 1. For KIK, solidus point was 1,209.3 +/- 3.2 degrees C, liquidus point was 1,308.3 +/- 7.10 degrees C, and melting expansion rate was 0.41+/- 0.16%. 2. For J2, solidus point was 1,198.3 +/- 0.6 degrees C, liquidus point was 1,253.0 +/- 4.4 degrees C, and melting expansion rate was 4.50 +/- 0.80%. 3. At high temperature, the mechanical characteristics of KIK greatly differed from those of J2. The risk of causing deformation during porcelain baking was suggested for KIK. Removal of segregation during casting was considered difficult in J2. 相似文献
90.
A rapid and sensitive screening assay has been established for in vitro evaluation of antiviral compounds against bovine viral diarrhoea virus (BVDV), which is widely used as a surrogate for hepatitis C virus (HCV). The procedure is based on photospectrometrical assessment for the viability of virus-infected cells via extracellular leakage of lactic dehydrogenase (LDH). The level of LDH in culture supernatants of BVDV-infected Madin-Darby bovine kidney (MDBK) cells was significantly higher than those of mock-infected MDBK cells. Under optimized assay conditions, the LDH level was found to correlate well with the degree of viral replication. When the 50% effective concentrations (EC50s) of ribavirin, cyclosporine A and human interferon-alpha for BVDV replication were determined by the established LDH method and compared with those obtained by a conventional tetrazolium colorimetric (MTT) method, there was a complete correlation in EC50s between the two methods. Furthermore, a much higher ratio of background activity (noise) to sample activity (signal) could be achieved with the LDH method than with the MTT method, indicating that the present LDH assay permits a sensitive, rapid and reliable screening of compounds for their anti-BVDV activity and may be useful for the discovery of novel anti-HCV agents. 相似文献