全文获取类型
收费全文 | 47886篇 |
免费 | 2493篇 |
国内免费 | 1110篇 |
专业分类
耳鼻咽喉 | 267篇 |
儿科学 | 1371篇 |
妇产科学 | 224篇 |
基础医学 | 2429篇 |
口腔科学 | 99篇 |
临床医学 | 7151篇 |
内科学 | 9262篇 |
皮肤病学 | 253篇 |
神经病学 | 2493篇 |
特种医学 | 1341篇 |
外科学 | 4443篇 |
综合类 | 9629篇 |
预防医学 | 2908篇 |
眼科学 | 225篇 |
药学 | 5679篇 |
48篇 | |
中国医学 | 2190篇 |
肿瘤学 | 1477篇 |
出版年
2024年 | 37篇 |
2023年 | 571篇 |
2022年 | 1258篇 |
2021年 | 1857篇 |
2020年 | 1714篇 |
2019年 | 1343篇 |
2018年 | 1402篇 |
2017年 | 1538篇 |
2016年 | 1793篇 |
2015年 | 1697篇 |
2014年 | 4138篇 |
2013年 | 3913篇 |
2012年 | 3475篇 |
2011年 | 3552篇 |
2010年 | 2784篇 |
2009年 | 2410篇 |
2008年 | 2310篇 |
2007年 | 2345篇 |
2006年 | 2094篇 |
2005年 | 1716篇 |
2004年 | 1364篇 |
2003年 | 1145篇 |
2002年 | 849篇 |
2001年 | 809篇 |
2000年 | 674篇 |
1999年 | 586篇 |
1998年 | 479篇 |
1997年 | 443篇 |
1996年 | 383篇 |
1995年 | 333篇 |
1994年 | 324篇 |
1993年 | 228篇 |
1992年 | 199篇 |
1991年 | 205篇 |
1990年 | 193篇 |
1989年 | 148篇 |
1988年 | 172篇 |
1987年 | 132篇 |
1986年 | 101篇 |
1985年 | 142篇 |
1984年 | 113篇 |
1983年 | 59篇 |
1982年 | 88篇 |
1981年 | 75篇 |
1980年 | 74篇 |
1979年 | 55篇 |
1978年 | 41篇 |
1977年 | 39篇 |
1976年 | 20篇 |
1975年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
21.
22.
23.
24.
Preliminary study on blood coagulation and hemostatic effect and acute toxicity of Oxalis corniculata L. ethanol extract 下载免费PDF全文
In the present study, we aimed to observe the effects of ethanol extract of Oxalis corniculata L. on bleeding time (BT) and coagulation time (CT) and determine its acute toxicity in mice. Firstly, the ethanol extract of O. corniculata was administered to 40 mice, which were randomly divided into the normal control group, Yunnan Baiyao control group, low-dose group, and high-dose group. The low-dose (0.6 g/kg) and high-dose (1.2 g/kg) groups received ethanol extract of O. corniculata by gavage, and the BT and CT of the mice were measured by the slide method and tail clipping method, respectively. Secondly, the median lethal dose method was used with 50 mice to observe the physiological state, poisoning reaction, and death of the mice after intragastric administration. Finally, on the 14th day of the experiment, a necropsy was performed to observe any abnormality of the organs. In conclusion, in the coagulation and hemostasis tests, there were no statistical differences between the groups (P > 0.05), while there was a significant dose-response relationship, and the BT and CT were significantly shorter than those of the negative control group, which were comparable to the Yunnan Baiyao control group. Moreover, in the acute toxicity test, the median lethal dose of ethanol extract of O. corniculata was 6.0291 g/kg, with a 95% confidence interval of 5.3065–6.7829 mg/kg. 相似文献
26.
27.
Hepatitis E virus (HEV) is the most common cause of acute liver failure (LF) and one of the most common factors causing acute injury in acute-on-chronic LF (ACLF). When HEV-related LF occurs, a series of changes take place in both the intrahepatic environment and extrahepatic microenvironment. The changed types and distribution of immune cells (infiltrating macrophages and increased lymphocytes) in liver tissue, as well the increased proinflammatory cytokines and chemokines in the blood, indicate that the occurrence and progression of HEV-related LF are closely related to immune imbalance. The clinical features and immune reaction in the body during HEV-related acute LF (ALF) and ACLF are complicated. This review highlights recent progress in elucidating the clinical manifestations of HEV-associated ALF and ACLF and discusses the corresponding systemic immune changes and possible regulatory mechanisms. 相似文献
28.
IntroductionSeptic arthritis is a serious orthopaedic emergency that must be diagnosed and managed early to prevent devastating complications. The current gold standard for diagnosing septic arthritis is synovial fluid culture, but results are delayed by 48–72 h, and the sensitivity of the test is very low. Differentiating Septic from non-septic arthritis is vital to prevent unnecessary use of antibiotics and prevent complications. Serum Procalcitonin (PCT) is a useful marker in differentiating septic from non-septic arthritis but there are very few studies that have studied the role of synovial PCT for the same.AimTo determine the role of serum and synovial PCT in differentiating acute Septic from non-septic arthritis.Materials and methodsProspective clinical study in which 60 patients presenting with acute inflammatory arthritis (<2 weeks duration) were enrolled from May 2018 to May 2020. Serum and synovial fluid samples were drawn at presentation and routine blood investigations, synovial fluid culture sensitivity, and Procalcitonin levels were measured. Patients were divided into 3 groups, with group-1 having confirmed pyogenic, group-2 having presumed pyogenic, and group-3 having non –pyogenic patients, respectively. All data was tabulated and statistically analysed using appropriate tests.ResultsMean serum PCT values in groups 1, 2 and 3 were 1.06 ± 1.11, 0.85 ± 0.74, and 0.11 ± 0.24, respectively. Patients in the Pyogenic group (group1 and group 2) had significantly higher mean serum PCT as compared to group3 (p < 0.0001). Group 1 had higher serum PCT as compared to group 2, but the difference was not significant (p = 0.58). Mean synovial PCT in group 1, 2 and 3 were 2.42 ± 1.98, 1.89 ± 1.18, and 0.22 ± 0.40, respectively. Patients in the Pyogenic group (Group1 and Group2) had significantly higher mean synovial PCT as compared to Group 3 (p < 0.0001). Group 1 had higher mean synovial PCT as compared to group 2, but the difference was not significant (p = 0.54). The area under the ROC curve of the serum levels of PCT was 0.0.895, and the area under the ROC curve of the synovial fluid levels of PCT was 0.914, which was higher than the serum PCT level.ConclusionSerum and synovial Procalcitonin may be used as a diagnostic marker in differentiating septic from inflammatory arthritis and can help in reducing unnecessary use of antibiotics and early diagnosis and management of septic arthritis, thereby preventing complications. 相似文献
29.
30.