全文获取类型
收费全文 | 6927篇 |
免费 | 430篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 188篇 |
妇产科学 | 76篇 |
基础医学 | 1065篇 |
口腔科学 | 132篇 |
临床医学 | 463篇 |
内科学 | 1793篇 |
皮肤病学 | 344篇 |
神经病学 | 515篇 |
特种医学 | 160篇 |
外科学 | 1195篇 |
综合类 | 25篇 |
一般理论 | 3篇 |
预防医学 | 181篇 |
眼科学 | 95篇 |
药学 | 450篇 |
中国医学 | 29篇 |
肿瘤学 | 615篇 |
出版年
2023年 | 39篇 |
2022年 | 72篇 |
2021年 | 111篇 |
2020年 | 68篇 |
2019年 | 105篇 |
2018年 | 131篇 |
2017年 | 111篇 |
2016年 | 151篇 |
2015年 | 140篇 |
2014年 | 166篇 |
2013年 | 223篇 |
2012年 | 349篇 |
2011年 | 397篇 |
2010年 | 197篇 |
2009年 | 171篇 |
2008年 | 317篇 |
2007年 | 368篇 |
2006年 | 331篇 |
2005年 | 317篇 |
2004年 | 369篇 |
2003年 | 361篇 |
2002年 | 368篇 |
2001年 | 230篇 |
2000年 | 198篇 |
1999年 | 178篇 |
1998年 | 96篇 |
1997年 | 57篇 |
1996年 | 53篇 |
1995年 | 53篇 |
1994年 | 57篇 |
1993年 | 49篇 |
1992年 | 134篇 |
1991年 | 132篇 |
1990年 | 134篇 |
1989年 | 146篇 |
1988年 | 86篇 |
1987年 | 121篇 |
1986年 | 83篇 |
1985年 | 90篇 |
1984年 | 74篇 |
1983年 | 61篇 |
1982年 | 40篇 |
1981年 | 29篇 |
1980年 | 29篇 |
1979年 | 45篇 |
1978年 | 38篇 |
1977年 | 36篇 |
1971年 | 27篇 |
1969年 | 31篇 |
1967年 | 29篇 |
排序方式: 共有7380条查询结果,搜索用时 15 毫秒
101.
102.
Recombinant human soluble thrombomodulin (rhsTM) was compared with various anticoagulants for in vitro anticoagulant effects on thrombin generation, clotting time, and thromboelastography. rhsTM as well as APC reduced the level of the peak of the thrombin generation curve, but we did not observe any time-delay to reach the peak. This effect of rhsTM was diminished in PC-deficient plasma and was closely associated with the inhibitory effect on prothrombinase and factor Va. On the other hand, hirudin and argatroban delayed the time to reach the level of the peak, without reducing it. rhsTM and other anticoagulants except for activated protein C (APC) were found to have concentration-dependent anticoagulant activity by conventional clotting tests. However, the concentration of rhsTM for clotting time was slightly affected by anti-protein C antibody. Moreover, the concentration of rhsTM required to inhibit thrombin activity directly was 50 times higher than that needed to inhibit thrombin generation. The effect of rhsTM on clot development was compared with that of other anticoagulants by thromboelastography; rhsTM reduced the growth of the clot but had little effect on the time to activate clotting, while the other anticoagulants had the opposite effect. This effect of rhsTM was completely abolished by the addition of anti-protein C or anti-protein S antibody. These findings suggest that rhsTM attenuates blood clotting by reducing the level of generated thrombin through protein C activation and subsequent factor Va inactivation and prothrombinase inhibition. 相似文献
103.
Asano M Inamura N Hatori C Sawai H Fujiwara T Abe Y Kayakiri H Satoh S Oku T Nakahara K 《Immunopharmacology》1999,43(2-3):163-168
Orally active nonpeptide bradykinin (BK) B2 receptor antagonists have been discovered by using directed random screening and chemical modification. These compounds displaced [3H]BK binding to B2 receptors in guinea-pig ileum membranes, rat uterus membranes and human lung fibroblasts with nanomolar IC50s. They did not inhibit different specific radio-ligand bindings to other receptor sites including B2 receptors. In isolated guinea-pig ileum preparations, these compounds had no agonistic effect on smooth muscle contraction at 10(-6) M, and caused parallel rightward shifts of the concentration-response curves to BK on contraction with higher p A2 values. They also blocked human B2 receptor-mediated phosphatidylinositol hydrolysis without agonistic effect. In vivo, the oral administrations of these antagonists potently inhibited BK-induced bronchoconstriction in guinea-pigs. They also reduced carrageenin-induced paw edema and caerulein-induced pancreatitis in rats. Moreover, these compounds alleviated kaolin-induced pain in mice by oral administration. These results show that our compounds are potent, selective, and orally active BK B2 receptor antagonists and that they may have therapeutic potential against inflammatory diseases and pain. 相似文献
104.
O. Suzuki M. Oya A. Kido Y. Katsumata M. Asano 《International journal of legal medicine》1980,86(1):35-39
Summary A simple qualitative method for identification of seminal stains based on a high activity of -glutamyltransferase (-GTP) in human semen is described. It employs the release of -naphthylamine from N--glutamyl--naphthylamide by the -GTP action; -naphthylamine couples with Fast Garnet GBC salt to produce a strong brownish-red color. The data on its simplicity, specificity, and stability show that the present method is suitable for medicolegal examination of seminal stains as a preliminary test. 相似文献
105.
106.
We studied the viability of canine pancreatic grafts using a short-time perfusion technique with an organ perfusion machine, "ORPH3000C". The following parameters were examined during perfusion of warm ischemically damaged grafts: Amylase, lipase, and insulin levels in the perfusate after 1-hr perfusion showed no significant correlation with warm ischemic time (WIT), and these indices could not be used to assess graft viability. Tissue flow rate (TFR) at the end of perfusion was significantly decreased with prolonged WIT. TFR correlated with the percent decrease in tissue SOD activity, thus TFR was a reliable predictor of reperfusion injury. Histological studies showed no findings attributable to warm ischemic injury before 1-hr perfusion. After 1-hr perfusion, the grafts were allotransplanted and the relation between TFR and endocrine function of the transplanted grafts was examined. TFR correlated with K value calculated from IV-GTT performed on day 5 postoperatively, suggesting that TFR is a predictable index of isolated pancreatic graft viability. Using TFR levels, this method allowed us to select only grafts with good function prior to transplantation. This technique appears to be of use for pancreatic transplantation from cadaver donors after cardiac arrest. 相似文献
107.
A 16-year-old female presented with a rare case of subepicranial varix in the left temporal area manifesting as a soft mass in the left temporal area when she laid down in the left lateral position. Bulging of the mass was observed when intracranial venous pressure was raised by the Valsalva maneuver, the left lateral position, or the prone position. Bone window computed tomography (CT) revealed a tiny hole, 1 mm in diameter, in the outer bone table. Three-dimensional CT (3D-CT) angiography clearly visualized a mass with a diameter of approximately 10 mm connected to the diploic vein. The mass was totally resected by operation. Venous bleeding was observed from the tiny hole. Histological examination revealed a venous lesion mimicking sinus pericranii and containing endothelial cells. No communication with the intracranial venous sinuses was identified, so the diagnosis was subepicranial varix. Radiological examination by direct injection of contrast medium is usually performed to identify subepicranial varix, but 3D-CT angiography is a non-invasive preoperative examination that can visualize this small venous lesion. Adjustment of the CT acquisition conditions may allow 3D-CT angiography to identify sinus pericranii in the future. 相似文献
108.
Asano Y 《Nihon Geka Gakkai zasshi》2000,101(11):791-793
Although toxic substances can be removed by blood purification techniques such as hemodialysis and hemoperfusion, the complete elimination of toxic substances from the whole body is difficult even if clearance values are high. Blood purification over in a limited time sometimes cannot prevent the death of patients, because the volume of distribution of toxic substances is usually very high. It should also be stressed that initial general management of patients is very important whenever blood purification procedures are utilized. 相似文献
109.
Expression of estrogen receptor alpha and beta mRNAs in prostate cancers treated with leuprorelin acetate 总被引:2,自引:0,他引:2
OBJECTIVE: The discovery of a novel estrogen receptor (ER), ER-beta, has given rise to new possibilities regarding estrogen's roles in the prostate. Although ER-beta is reported to be expressed preferentially in the rat prostate, its expression in the human prostate and relationship to cancer development has not been investigated. Thus the purpose of the study was to examine mRNA levels of ER-alpha and ER-beta in benign prostatic hyperplasia and prostate carcinoma. METHODS: Samples of 15 prostate cancers obtained at radical prostatectomy were examined. All the patients had been maintained on androgen withdrawal therapy for at least 3 months. ER-alpha and ER-beta mRNAs were measured with a competitive PCR technique. RESULTS: Both ER-alpha and ER-beta mRNAs were detected in all of the prostate cancer tissues examined, as well as in PC3 and LNCap cells, although the levels varied among specimens. Interestingly, both types were significantly decreased in cases with lymph node metastasis. However, there was no correlation between ER mRNA levels and any other clinicopathological parameters. CONCLUSIONS: (1) Both ER-alpha and ER-beta mRNAs are expressed in prostate cancer and (2) expression of ER mRNA may not be related to cancer progression but may be negatively correlated with metastasis. 相似文献