首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1422篇
  免费   70篇
  国内免费   24篇
耳鼻咽喉   6篇
儿科学   148篇
妇产科学   18篇
基础医学   134篇
口腔科学   19篇
临床医学   156篇
内科学   246篇
皮肤病学   15篇
神经病学   114篇
特种医学   29篇
外科学   110篇
综合类   98篇
预防医学   224篇
眼科学   8篇
药学   107篇
  1篇
中国医学   19篇
肿瘤学   64篇
  2023年   61篇
  2022年   101篇
  2021年   110篇
  2020年   89篇
  2019年   83篇
  2018年   86篇
  2017年   31篇
  2016年   40篇
  2015年   44篇
  2014年   89篇
  2013年   105篇
  2012年   47篇
  2011年   68篇
  2010年   88篇
  2009年   44篇
  2008年   72篇
  2007年   62篇
  2006年   41篇
  2005年   33篇
  2004年   22篇
  2003年   24篇
  2002年   19篇
  2001年   17篇
  2000年   20篇
  1999年   15篇
  1998年   7篇
  1997年   10篇
  1996年   6篇
  1995年   9篇
  1994年   3篇
  1993年   6篇
  1992年   10篇
  1991年   4篇
  1990年   3篇
  1989年   11篇
  1988年   8篇
  1987年   3篇
  1986年   3篇
  1985年   3篇
  1983年   3篇
  1981年   1篇
  1979年   1篇
  1978年   2篇
  1976年   2篇
  1975年   1篇
  1974年   3篇
  1973年   1篇
  1971年   2篇
  1969年   1篇
  1968年   1篇
排序方式: 共有1516条查询结果,搜索用时 0 毫秒
31.
Reports of racial and ethnic disparities regarding both rates of infection of the SARS-CoV-2 virus and morbidity of the coronavirus disease-19 (COVID-19) contain profound differences depending on the population. Our previous study has shown that patients with COVID-19 who developed hypertriglyceridemia during hospitalization have a 2.3 times higher mortality rate. However, whether the correlation between hypertriglyceridemia and mortality has disparity among different racial and ethnic groups is unknown.In this study, we investigated the impact of race/ethnicity on the correlation between hypertriglyceridemia and mortality in hospitalized patients with COVID-19. De-identified information from 904 hospitalized patients diagnosed with COVID-19 between March 2020 and June 2021 were extracted from the Medical College of Wisconsin Clinical Data Warehouse. A multivariable regression analysis suggested that the Asians and non-White Hispanics had 4 or 3.9 times higher mortality rate, respectively, after adjusting for age, morbid obesity (BMI ≥40), and gender. The hypertriglyceridemia (≥150 mg/dL) was associated with higher mortality, after adjusting for age, gender, and morbid obesity. The baseline hypertriglyceridemia occurrence had relevantly more consistent percentages among all racial/ethnic groups. However, non-White Hispanic and Asian patients had the highest frequencies of peak hypertriglyceridemia occurrence during hospitalization. The peak hypertriglyceridemia developed during hospitalization correlates with the incidence of thrombosis after adjusting for morbid obesity, age, and sex. In summary, in this retrospective study of 904 hospitalized COVID-19 patients, Asians and non-White Hispanics had a greater likelihood of developing hypertriglyceridemia during hospitalization and mortality than White patients.  相似文献   
32.
目的探讨糖耐量减低(IGT)患者早期糖尿病肾病的预测指标、患病率及影响因素。方法262例受试者中正常糖耐量(NGT)103人、IGT98人、糖尿病(DM)61人,全部进行即刻尿转铁蛋白/肌酐(UTRF/Cr)和尿白蛋白/肌酐(UAlb/Cr)的检测及临床观察指标的测定。结果(1)UTRF/Cr与UAlb/Cr呈显著正相关,r=0.618,P<0.001。(2)IGT组的UAlb/Cr(中位数,极差)、UTRF/Cr(中位数,极差)高于NGT组(0.015,0.44mg/mg比0.012,0.58mg/mg,t=-1.981,P=0.049;0.064,4.96mg/mg比0.034,7.30mg/mg,t=-2.249,P=0.026)。(3)各组UTRF/Cr比值的阳性率明显高于白蛋白尿的阳性率(41.6%比29.7%,P(0.01)。(4)Logistic回归分析显示白蛋白尿的主要危险因素是DBP,OR=1.064,2hPGOR=1.109,P<0.01;非糖尿病组的主要危险因素是DBP,OR=1.064,P<0.01。结论在IGT阶段已存在早期糖尿病肾脏损害,高血压是其重要的危险因素。尿转铁蛋白/肌酐比值的检测较白蛋白尿/肌酐比值更灵敏,但仍需进一步综合比较二者的敏感性和特异性。  相似文献   
33.
Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP.  相似文献   
34.
Healthcare problems observed in the majority of end-stage renal disease (ESRD) patients regarding hemodialysis (HD) treatment are serious issues for the Taiwanese healthcare services, and an interesting topic is thus the adequacy of HD therapy. This study successfully models a hybrid procedure to measure HD adequacy to assess therapeutic effects and to explore the relationship between accuracy and coverage for interested parties. The proposed model has better accuracy, a lower standard deviation, and fewer attributes than the listed methods under various evaluation criteria. The study results are useful to subsequent researchers to develop suitable applications, and to ESRD patients and their doctors to ensure satisfactory medical quality.  相似文献   
35.
《Annals of human biology》2013,40(5):372-381
Background: Although Tanner was not directly involved in physical education or the sport sciences, several of his papers addressed issues related to research in the area.

Aim: To consider the implications of selected papers and research projects for the sport sciences.

Papers and Implications: Several early papers addressed ratio standards, somatotype and total cholesterol, and anthropometric and somatotype changes associated weight training and cessation of training in young adult men. The papers have, respectively, implications for current studies of allometric scaling, physique and risk factors for cardiovascular and metabolic complications, and responses to training. The survey of athletes at the 1960 Rome Olympic Games not only added to the literature but to some extent also set the stage for subsequent surveys of Olympic athletes in 1968, 1972 and 1976. Although not directly involved in the mixed-longitudinal study of Training of Youth Athletes (TOYA) in several sports, it was conducted in his department. Results from TOYA indicated no influence of systematic training for sport on growth in height, young adult height and sexual maturation. Growth at Adolescence was also a fixture in many graduate programs.

Conclusion: Though not a sport scientist, Tanner contributed directly and indirectly to the field.  相似文献   
36.
《Pancreatology》2021,21(6):1112-1118
ObjectiveTo determine the risk association between fasting glucose levels and pancreatic cancer using systematically collected prediagnostic blood glucose samples.MethodsProspective nested case-control study of participants from the Northern Sweden Health and Disease Study, including 182 cases that developed pancreatic cancer and four matched controls per case. Blood glucose levels collected up to 24 years before pancreatic cancer diagnosis were analyzed. The association between fasting glucose levels and pancreatic cancer risk was determined using unconditional and conditional logistic regression models. The association between fasting glucose and the time to pancreatic cancer diagnosis, tumor stage and survival was determined using likelihood-ratio test, t-test and log rank test.ResultsThe unadjusted risk of developing pancreatic cancer increased with increasing fasting glucose levels (OR 1.30, 95% CI 1.05–1.60, P = .015). Impaired fasting glucose (≥6.1 mmol/L) was associated with an adjusted risk of 1.77 for developing pancreatic cancer (95% CI 1.05–2.99, P = .032). In subgroup analysis, fasting glucose levels were associated with an increased risk in never-smokers (OR 4.02, 95% CI 1.26–12.77, P = .018) and non-diabetics (OR 3.08, 95% CI 1.08–8.79, P = .035) (non-significant for interaction). The ratio between fasting glucose and BMI was higher among future pancreatic cancer patients and an increased ratio was associated with elevated risk of pancreatic cancer (OR 1.66, 95% CI 1.04–2.66, P = .034). Fasting glucose levels were not associated with TNM stage at diagnosis or survival.ConclusionsHigh fasting glucose is associated with an increased risk of being diagnosed with pancreatic cancer.  相似文献   
37.
38.
39.
40.

Background:

Tertiary hospitals serve as the medical service center within the region and play an important role in the medical and health service system. They are also the key targets of public hospital reform in the new era in China. Through the reform of health system, the public hospital efficiency has changed remarkably. Therefore, this study aimed to provide some advice for efficiency assessment of public hospitals in China by comparing and analyzing the consistency of results obtained by three commonly used methods for examining hospital efficiency, that is, ratio analysis (RA), stochastic frontier analysis (SFA), and data envelopment analysis (DEA).

Methods:

The theoretical basis, operational processes, and the application status of RA, SFA, and DEA were learned through literature analysis. Then, the empirical analysis was conducted based on measured data from 51 tertiary public hospitals in Beijing from 2009 to 2011.

Results:

The average values of hospital efficiency calculated by SFA with index screening and principal component analysis (PCA) results and those calculated by DEA with index screening results were relatively stable. The efficiency of specialized hospitals was higher than that of general hospitals and that of traditional Chinese medicine hospitals. The results obtained by SFA with index screening results and the results obtained by SFA with PCA results showed a relatively high correlation (r-value in 2009, 2010, and 2011 were 0.869, 0.753, and 0.842, respectively, P < 0.01). The correlation between results obtained by DEA with index screening results and PCA results and results obtained by other methods showed statistical significance, but the correlation between results obtained by DEA with index screening results and PCA results was lower than that between results obtained by SFA with index screening results and PCA results.

Conclusions:

RA is not suitable for multi-index evaluation of hospital efficiency. In the given conditions, SFA is a stable efficiency analysis method. In the evaluation of hospital efficiency, DEA combined with PCA should be adopted with caution due to its poor stability.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号