全文获取类型
收费全文 | 14200篇 |
免费 | 769篇 |
国内免费 | 93篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 284篇 |
妇产科学 | 268篇 |
基础医学 | 1624篇 |
口腔科学 | 339篇 |
临床医学 | 1009篇 |
内科学 | 3819篇 |
皮肤病学 | 372篇 |
神经病学 | 1017篇 |
特种医学 | 504篇 |
外国民族医学 | 2篇 |
外科学 | 2457篇 |
综合类 | 74篇 |
预防医学 | 451篇 |
眼科学 | 240篇 |
药学 | 952篇 |
中国医学 | 16篇 |
肿瘤学 | 1521篇 |
出版年
2023年 | 92篇 |
2022年 | 175篇 |
2021年 | 376篇 |
2020年 | 206篇 |
2019年 | 236篇 |
2018年 | 364篇 |
2017年 | 261篇 |
2016年 | 309篇 |
2015年 | 320篇 |
2014年 | 339篇 |
2013年 | 479篇 |
2012年 | 721篇 |
2011年 | 804篇 |
2010年 | 431篇 |
2009年 | 357篇 |
2008年 | 643篇 |
2007年 | 653篇 |
2006年 | 639篇 |
2005年 | 669篇 |
2004年 | 639篇 |
2003年 | 624篇 |
2002年 | 573篇 |
2001年 | 406篇 |
2000年 | 396篇 |
1999年 | 410篇 |
1998年 | 177篇 |
1997年 | 151篇 |
1996年 | 123篇 |
1995年 | 126篇 |
1994年 | 106篇 |
1993年 | 91篇 |
1992年 | 328篇 |
1991年 | 295篇 |
1990年 | 274篇 |
1989年 | 323篇 |
1988年 | 256篇 |
1987年 | 235篇 |
1986年 | 230篇 |
1985年 | 183篇 |
1984年 | 132篇 |
1983年 | 94篇 |
1980年 | 50篇 |
1979年 | 86篇 |
1978年 | 57篇 |
1977年 | 48篇 |
1975年 | 50篇 |
1974年 | 63篇 |
1973年 | 66篇 |
1972年 | 49篇 |
1969年 | 47篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
We report a case of dermatophytosis in a Judo wrestler caused by Trichophyton tonsurans (T. tonsurans) with clinical features that mimicked the concentric rings of tinea imbricata. Tinea imbricata is a unique dermatophytosis caused by Trichophyton concentricum (T. concentricum), observed endemically in subtropical to torrid zones and characterized by impressive concentric rings. We found three similar cases of the dermatophytosis in the literature that were reported as tinea pseudoimbricata or tinea indecisiva. All of these cases were associated with systemic or local immunosuppression, perhaps simulating the mechanism of tinea imbricata, which is known to involve the lack of delayed type hypersensitivity to T. concentricum. These cases imply that iatrogenic immunosuppression may perhaps play an important role in the development of the unique clinical features mimicking tinea imbricata. Furthermore, three of the four cases, including the presented case, were caused by T. tonsurans. It may be necessary to consider T. tonsurans infection when multiple concentric erythemas are encountered. 相似文献
992.
993.
994.
995.
Funabiki K Onishi K Tanabe M Kuru S Konagaya M Sato F Ito M Nakano T 《International journal of cardiology》2005,98(1):161-162
Cardiac involvement in limb girdle muscular dystrophy has considered to be rare. This is the first report showing the electron microscopic findings of dilated cardiomyopathy (DCM) accompanied with limb girdle muscular dystrophy. The findings described in this report indicate that limb girdle muscular dystrophy may be yet another cause of DCM. 相似文献
996.
BACKGROUND/AIMS: Serum aminotransferase, a sensitive marker of hepatocellular damage, often poorly correlates with the severity of damage. Serum nuclear matrix protein (NMP), a structural protein released from dead cell nuclei, is investigated as a candidate marker of organ damage in liver disease. METHODOLOGY: Serum NMP and aminotransferase levels of 134 patients with various liver diseases and 26 healthy individuals were examined. RESULTS: Patients with chronic viral hepatitis showed slightly higher NMP levels (17.8 U/mL; 95% CI 15.0-20.5 U/mL) than those of healthy individuals (6.05 U/mL; 95% CI 4.82-7.27 U/mL). Their NMP values had no correlation with aminotransferase levels. NMP levels were similar irrespective of liver disease progression, whereas aminotransferase values decreased in parallel with progression. Patients with autoimmune hepatitis or primary biliary cirrhosis who were under an appropriate treatment as well as individuals with fatty liver showed no elevation of serum NMP levels. Patients with acute viral hepatitis showed very high NMP levels (38.8 U/mL; 95%CI 27.6-50.0 U/mL) that correlated with serum aminotransferase levels in their sera. CONCLUSIONS: In chronic liver diseases, the serum NMP level elevates to various degrees independent from the degree of aminotransferase elevation. Serum NMP, putatively representing the number of dead cells, is a candidate as an indicator of organ damage severity in liver disease. 相似文献
997.
BACKGROUND/AIMS: Extraparenchymal control of the main hepatic veins (ECHV) and use of vascular staplers are now considered as effective methods to prevent intraoperative hemorrhage and duration of hepatic transection. The aim of the present preliminary study was to investigate whether extraparenchymal control of the hepatic veins combined with inflow occlusion and a new articulating linear stapler without a knife (Endocutter no-knife) were effective for major hepatectomy. METHODOLOGY: Twenty patients with hepatic malignant disease underwent major hepatectomies in which 4 or more Couinaud's segments were removed. Extraparenchymal control of the hepatic veins and Endocutter no-knife were used in 7 (Recent group) of the 20 patients after June 2003. Hemihepatic devascularization before hepatic transection, and intermittent hepatic inflow occlusion were also performed in these 7 patients. In the other 13 (Previous group) patients before June 2003, major hepatectomy was performed under only intermittent hepatic inflow occlusion. Intraoperative blood loss volume, transfusion of packed red blood cells, and duration of hepatic transection were compared between the Recent group and Previous group. RESULTS: Estimated blood loss and number of intraoperative blood transfusion were significantly smaller in the Recent group than in the Previous group. Duration of hepatic transection was also significantly shorter in the Recent group than in the Previous group. CONCLUSIONS: The present preliminary study showed that extraparenchymal control of the hepatic veins and Endocutter no-knife are useful for major hepatectomy. 相似文献
998.
Generation of reactive oxygen species by neutrophils and endothelial cell injury in normal and preeclamptic pregnancies 总被引:1,自引:0,他引:1
The aim of this study was to investigate the role of neutrophil-derived reactive oxygen species on endothelial cell dysfunction in preeclampsia. We first assessed the correlation between nitrite and superoxide anion production in normal nonpregnant (n=10), normal pregnant (n=15), and preeclamptic women (n=12). We then examined neutrophil-mediated oxygen radical damage to human umbilical vein endothelial cells in vitro. Neutrophil superoxide release was measured by cytochrome C reduction; nitrite release was measured by the modified Griess reaction, and endothelial cell injury was measured by 51Cr release. N-formyl-methionyl-leucyl-phenylalanine-stimulated superoxide release by neutrophils was significantly increased in women with preeclampsia compared with the other 2 groups. Nitrite release by neutrophils was significantly decreased in preeclampsia compared with normal pregnancy. When neutrophils were pretreated with superoxide dismutase, nitrite release by neutrophils did not differ between normal pregnancy and preeclampsia, suggesting that excess superoxide anion in preeclampsia could reduce bioavailability of nitric oxide through neutrophil autocrine function. Neutrophil-mediated endothelial cell injury was significantly greater in women with preeclampsia than in the other 2 groups. Hydrogen peroxide was important in neutrophil-mediated endothelial cell injury in preeclampsia as catalase inhibited endothelial cell injury. When neutrophils were pretreated with NG-nitro-L-arginine methyl ester, neutrophil-mediated endothelial cell injury in preeclampsia was decreased, indicating a role for peroxynitrite formation as a mechanism of endothelial cell injury. In conclusion, the modulation of neutrophils causing superoxide production to dominate over nitrite release provides a reasonable explanation for endothelial cell dysfunction in preeclampsia. 相似文献
999.
Fujimoto S Inoue A Hisatake S Yamashina S Yamashina H Nakano H Yamazaki J 《Nuclear medicine communications》2005,26(2):97-102
OBJECTIVE: Large-scale clinical trials have demonstrated that beta blocker therapy improves the prognosis of dilated cardiomyopathy (DCM), but cardiac events sometimes occur even in patients showing favourable response to the therapy. In this study, the usefulness of meta-iodobenzyguanidine (MIBG) in predicting cardiac events was investigated in DCM patients successfully receiving long-term treatment with beta blockers. METHODS: The subjects were 53 patients with DCM (including 10 women; mean age, 56.5+/-10.9 years) who could continue beta blocker therapy for more than 6 months. MIBG was performed within 1 year of commencing the therapy. The extent score, severity score and washout rate were obtained from single photon emission computed tomography images. At the same time, left ventricular ejection fraction (LVEF) and left ventricular end diastolic diameters were measured by echocardiography. The endpoints were cardiac events (cardiac death and admission to hospital due to heart failure or arrhythmia), and patients were observed for an average of 1314+/-986 days (150-4100 days). RESULTS: Cardiac events occurred in nine patients during the observation period. The multivariate statistical analysis demonstrated that the delayed extent score was the strongest significant predictive factor, (hazard ratio 1.036, P<0.01). while LVEF was not a predictive factor. Both the improvement of LVEF and MIBG were significant predictive factors. The improvement of washout rate was the strongest. CONCLUSION: Parameters of MIBG but not of LVEF were useful in predicting cardiac events in DCM patients whose condition had been successfully stabilized by the introduction of beta blockers. 相似文献
1000.
We report a case of metastatic pulmonary calcification that appeared on high-resolution CT (HRCT) as multiple, lobular, ground-glass opacities sparing the perilobular area. Diffuse metastatic calcification such as that in our case was considered to be a result of postoperative transient acute renal failure. Decreasing alveolar air spaces due to both alveolar septal fibrosis and calcification caused the diffuse ground-glass opacities in the present case. 相似文献