全文获取类型
收费全文 | 3759篇 |
免费 | 257篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 127篇 |
妇产科学 | 155篇 |
基础医学 | 387篇 |
口腔科学 | 162篇 |
临床医学 | 330篇 |
内科学 | 667篇 |
皮肤病学 | 144篇 |
神经病学 | 184篇 |
特种医学 | 134篇 |
外国民族医学 | 3篇 |
外科学 | 629篇 |
综合类 | 76篇 |
一般理论 | 3篇 |
预防医学 | 248篇 |
眼科学 | 102篇 |
药学 | 414篇 |
中国医学 | 25篇 |
肿瘤学 | 229篇 |
出版年
2024年 | 6篇 |
2023年 | 61篇 |
2022年 | 174篇 |
2021年 | 231篇 |
2020年 | 161篇 |
2019年 | 221篇 |
2018年 | 248篇 |
2017年 | 151篇 |
2016年 | 156篇 |
2015年 | 154篇 |
2014年 | 164篇 |
2013年 | 250篇 |
2012年 | 298篇 |
2011年 | 324篇 |
2010年 | 167篇 |
2009年 | 111篇 |
2008年 | 178篇 |
2007年 | 148篇 |
2006年 | 146篇 |
2005年 | 107篇 |
2004年 | 119篇 |
2003年 | 88篇 |
2002年 | 71篇 |
2001年 | 34篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 22篇 |
1997年 | 12篇 |
1996年 | 12篇 |
1995年 | 7篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 21篇 |
1990年 | 15篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 11篇 |
1985年 | 9篇 |
1984年 | 16篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1976年 | 9篇 |
1973年 | 4篇 |
1972年 | 5篇 |
1966年 | 5篇 |
排序方式: 共有4060条查询结果,搜索用时 0 毫秒
61.
Walid Shehab-Eldin Ahmed El-ashmawy Mahmoud K. Ahmed Nesreen Elhelbawy Alaaeldin Dawood Mostafa Elnajjar 《Journal of the Saudi Heart Association》2020,32(4):490
BackgroundThe relationship between glycemic control and the risk of cardiac disease in patients with Type 2 Diabetes Mellitus (T2DM) is controversial. 1,5-Anhydroglucitol (1,5-AG) is a biomarker of Glucose Variability (GV) and has been associated with clinical cardiovascular disease. However, its association with Subclinical Cardiac Disease (SCD) is unknown.Aim of the workStudy the association between GV and SCD.Subjects and methodsA cross-sectional study was conducted on 46 asymptomatic patients with T2DM as T2DM individuals group. Another 46 non-diabetic age and sex matched subjects were included as the healthy group. 1,5-AG was measured for all subjects. M-mode echocardiography in parasternal long axis view was used to measure Left Ventricular (LV) end diastolic dimension, LV end systolic dimension, ejection fraction, interventricular septum, LV posterior wall thickness, LV fractional shortening, left atrial dimension and aortic root dimension. Global Longitudinal Strain (GLS) was assessed by speckled tracking echocardiography.ResultsThere were no significant differences between both groups as regarding age, sex, BMI, AST, ALT, and serum creatinine. 1,5-AG was lower in T2DM individuals group. As regarding the echo parameters no significant difference found between both groups regarding left ventricular, left atrial and aortic root dimensions. T2DM individuals group showed a statistically significant higher mitral valve area, apical 2 chambers, apical 4 chambers, apical longitudinal axis and GLS. No correlation found between HbA1c and any echo parameters while 1,5-AG showed a significantly negative correlation with apical 2 chambers, apical 4 chambers, apical longitudinal axis and GLS. ROC curve analysis detected 1,5-AG less than 7.51 ng/ml as the best cut off value with sensitivity of 85.7%, specificity 75% to diagnose patients with T2DM and SCD.Conclusion1,5-AG might be used as an additional surrogate marker to identify patients with T2DM and SCD. 相似文献
62.
Ibrahim H. Eissa Ahmed M. Metwaly Amany Belal Ahmed B.M. Mehany Rezk R. Ayyad Khaled El‐Adl Hazem A. Mahdy Mohammed S. Taghour Kamal M.A. El‐Gamal Mohamad E. El‐Sawah Souad A. Elmetwally Mostafa. A. Elhendawy Mohamed M. Radwan Mahmoud A. ElSohly 《Archiv der Pharmazie》2019,352(11)
In continuation of our previous work on the design and synthesis of topoisomerase II (Topo II) inhibitors and DNA intercalators, a new series of quinoxaline derivatives were designed and synthesized. The synthesized compounds were evaluated for their cytotoxic activities against a panel of three cancer cell lines (Hep G‐2, Hep‐2, and Caco‐2). Compounds 18b, 19b, 23, 25b , and 26 showed strong potencies against all tested cell lines with IC50 values ranging from 0.26 ± 0.1 to 2.91 ± 0.1 µM, comparable with those of doxorubicin (IC50 values ranging from 0.65 ± 0.1 to 0.81 ± 0.1 µM). The most active compounds were further evaluated for their Topo II inhibitory activities and DNA intercalating affinities. Compounds 19b and 19c exhibited high activities against Topo II (IC50 = 0.97 ± 0.1 and 1.10 ± 0.1 µM, respectively) and bound the DNA at concentrations of 43.51 ± 2.0 and 49.11 ± 1.8 µM, respectively, whereas compound 28b exhibited a significant affinity to bind the DNA with an IC50 value of 37.06 ± 1.8 µM. Moreover, apoptosis and cell‐cycle tests of the most promising compound 19b were carried out. It was found that 19b can significantly induce apoptosis in Hep G‐2 cells. It has revealed cell‐cycle arrest at the G2/M phase. Moreover, compound 19b downregulated the Bcl‐2 levels, indicating its potential to enhance apoptosis. Furthermore, molecular docking studies were carried out against the DNA–Topo II complex to examine the binding patterns of the synthesized compounds. 相似文献
63.
64.
65.
Negin Badihian Roya Riahi Mostafa Qorbani Mohammad Esmaeil Motlagh Ramin Heshmat Roya Kelishadi 《Journal of clinical hypertension (Greenwich, Conn.)》2020,22(8):1434-1441
Although blood pressure (BP) tracks from childhood to adulthood, and the prevalence of pediatric primary hypertension is increasing, related determinants are not well understood. The role of noise pollution and psychological distress in increasing BP is well documented in adults, but it remains elusive in children. This study aims to investigate the association of noise annoyance and psychological distress with BP in a pediatric population. This national cross‐sectional study was conducted in 2015 on a sample of 14400 Iranian students, aged 7‐18 years. Information regarding noise annoyance and psychological distress were assessed using questionnaires, and BP values were measured. Levels of noise annoyance and psychological distress were classified based on tertiles to no/low, moderate, and high. Data of 14274 students were completed. The mean age of participants was 12.28 (0.05), with 51% boys and 71.4% urban inhabitant. Diastolic BP and mean arterial BP (MAP) had positive correlations with noise annoyance (regression coefficient: 0.028, 95 % CI: 0.005 ‐ 0.05 and 0.025, 95 % CI: 0.002 – 0.04, respectively). Participants with higher psychological distress were 15 % more likely to experience abnormally high BP compared to those with normal psychological status or mild distresses (OR: 1.15, 95 % CI: 1.003 – 1.34). Here, we found significant positive relationships between the level of noise annoyance and values of diastolic BP and MAP. Moreover, high psychological distress showed to increase the chance of abnormally high BP. The clinical impact of these findings should be assessed in further longitudinal studies. 相似文献
66.
Mohammad Saeid Rezaee Zavareh Seyed Moayed Alavian Hamidreza Karimisari Mostafa Shafiei Seyed Yasser Saiedi Hosseini 《Hepatitis monthly》2014,14(8)
Background:
Occult hepatitis C virus infection (OCI) is recognized by finding hepatitis C virus (HCV) RNA in hepatocytes without detectable anti-HCV antibodies and viral RNA in plasma. Autoimmune hepatitis (AIH) is a chronic and generally progressive disease without exactly-identified etiology.Objectives:
This study aimed to determine the prevalence of OCI among patients with AIH and to evaluate the tests used to rule out HCV infection in diagnosing AIH.Patients and Methods:
Between July 2012 to February 2013, 35 Iranian patients with AIH who attended Tehran Hepatitis Center were investigated. For identifying OCI, detection of HCV RNA in both ultracentrifuged serum samples and peripheral blood mononuclear cells (PBMCs) was used. Data analysis was performed using SPSS.Results:
Six males and 29 females with mean disease duration of 77.1 ± 39.5 month and mean age of 43.62 ± 12.67 years were investigated. All cases were negative for anti-HCV antibody and we could not find any HCV RNA in ultracentrifuged serum samples and PBMCs.Conclusions:
With our laboratory diagnostic method, it seems that there are no cases of OCI in patients with AIH. However, we recommend further studies with more samples and more precise laboratory method. 相似文献67.
68.
Mokhles MM Rizopoulos D Andrinopoulou ER Bekkers JA Roos-Hesselink JW Lesaffre E Bogers AJ Takkenberg JJ 《European heart journal》2012,33(17):2213-2224
Aims The objective of the present study was to report our ongoing prospective cohort of autograft recipients with up to 21 years of follow-up. Methods and results All consecutive patients (n = 161), operated between 1988 and 2010, were analysed. Mixed-effects models were used to assess changes in echocardiographic measurements (n = 1023) over time in both the autograft and the pulmonary allograft. The mean patient age was 20.9 years (range 0.05-52.7)-66.5% were male. Early mortality was 2.5% (n = 4), and eight additional patients died during a mean follow-up of 11.6 ± 5.7 years (range 0-21.5). Patient survival was 90% [95% confidence interval (CI), 78-95] up to 18 years. During the follow-up, 57 patients required a re-intervention related to the Ross operation. Freedom from autograft reoperation and allograft re-intervention was 51% (95% CI 38-63) and 82% (95% CI 71-89) after 18 years, respectively. No major changes were observed over time in autograft gradient, and allograft gradient and regurgitation. An initial increase of sinotubular junction and aortic anulus diameter was observed in the first 5 years after surgery. The only factor associated with an increased autograft reoperation rate was pre-operative pure aortic regurgitation (AR) (hazard ratio 1.88; 95% CI 1.04-3.39; P= 0.037). Conclusion We observed good late survival in patients undergoing autograft procedure without reinforcement techniques. However, over half of the autografts failed prior to the end of the second decade. The reoperation rate and the results of echocardiographic measurements over time underline the importance of careful monitoring especially in the second decade after the initial autograft operation and in particular in patients with pre-operative AR. 相似文献
69.
Sebastian J. Buss Mostafa Emami Derliz Mereles Grigorios Korosoglou Arnt V. Kristen Andreas Voss Dieter Schellberg Christian Zugck Christian Galuschky Evangelos Giannitsis Ute Hegenbart Anthony D. Ho Hugo A. Katus Stefan O. Schonland Stefan E. Hardt 《Journal of the American College of Cardiology》2012
70.
Rania M. Nada Bram van Loon Thomas J.J. Maal Stefaan J. Bergé Yehya A. Mostafa Anne Marie Kuijpers-Jagtman Jan GJH Schols 《Clinical oral investigations》2013,17(9):2017-2024