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   36128篇
  免费   2287篇
  国内免费   96篇
耳鼻咽喉   368篇
儿科学   880篇
妇产科学   752篇
基础医学   4772篇
口腔科学   781篇
临床医学   3346篇
内科学   7516篇
皮肤病学   553篇
神经病学   3891篇
特种医学   1447篇
外国民族医学   55篇
外科学   4764篇
综合类   451篇
一般理论   16篇
预防医学   3152篇
眼科学   941篇
药学   2466篇
中国医学   34篇
肿瘤学   2326篇
  2023年   120篇
  2022年   252篇
  2021年   557篇
  2020年   314篇
  2019年   547篇
  2018年   622篇
  2017年   514篇
  2016年   541篇
  2015年   708篇
  2014年   993篇
  2013年   1454篇
  2012年   2199篇
  2011年   2310篇
  2010年   1267篇
  2009年   1204篇
  2008年   2105篇
  2007年   2325篇
  2006年   2209篇
  2005年   2204篇
  2004年   2095篇
  2003年   1953篇
  2002年   1857篇
  2001年   490篇
  2000年   402篇
  1999年   430篇
  1998年   412篇
  1997年   376篇
  1996年   316篇
  1995年   312篇
  1994年   257篇
  1993年   256篇
  1992年   266篇
  1991年   229篇
  1990年   217篇
  1989年   252篇
  1988年   224篇
  1987年   214篇
  1986年   191篇
  1985年   191篇
  1984年   251篇
  1983年   210篇
  1982年   251篇
  1981年   227篇
  1980年   207篇
  1979年   173篇
  1978年   166篇
  1976年   151篇
  1975年   132篇
  1974年   157篇
  1973年   118篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
951.
BackgroundThe aim of this study was to examine whether time-dependent annual fasting plasma glucose (FPG) variation, as represented by coefficient of variation (CV), can predict mortality in subsequent all-cause, expanded, and nonexpanded cardiovascular disease-related mortality independent of mean FPG, renal function, mean hemoglobin A1C (HbA1C), HbA1C variation, and other risk factors in patients with type 2 diabetes.MethodsA computerized database of all patients with type 2 diabetes aged 30 years and over (n = 5008) enrolled in the Diabetes Care Management Program of China Medical University Hospital before 2007 was used in a time-dependent Cox proportional hazard regression model.ResultsThe mortality rates were 8.64, 12.71, and 30.82 per 1000 person-years in groups of first, second, and third tertiles of baseline FPG-CV, respectively. Among these patients with type 2 diabetes, 336, 1191, 914, 585, and 1979 patients provided 1, 2, 3, 4, and 5 or more years of annual FPG-CV measurements, respectively. After adjusting for mean FPG, mean HbA1C, HbA1C variation, and other risk factors, annual FPG-CV was independently associated with all-cause mortality and mortality due to expanded and nonexpanded cardiovascular disease, and the corresponding hazard ratios for third versus first tertile of annual FPG-CV were 5.53 (95% confidence interval [CI], 3.85-7.94), 3.21 (95% CI, 2.00-5.15), and 9.45 (95% CI, 5.37-16.63), respectively.ConclusionsTime-dependent variation of FPG was a strong predictor of all-cause, expanded, and nonexpanded cardiovascular disease-related mortality in patients with type 2 diabetes, suggesting that glucose variation may become a measure in clinical practice for the goal in the management of these patients.  相似文献   
952.
We conducted a prospective, inpatient fever study in malaria-endemic Papua, Indonesia to determine non-malaria fever etiologies. Investigations included malaria blood films, blood culture, paired serologic samples analysis for dengue, Japanese encephalitis, leptospirosis, scrub typhus, murine typhus, and spotted fever group rickettsia. During 1997-2000, 226 patients (127 males and 99 females) 1-80 years of age (median age = 25 years) were enrolled. Positive blood cultures (n = 34, 15%) were obtained for Salmonella Typhi (n = 13), Escherichia coli (n = 8), Streptococcus pneumoniae (n = 6), Staphylococcus aureus (n = 5), Streptococcus pyogenes (n = 1), and Klebsiella pneumoniae (n = 1). Twenty (8.8%) patients were positive for leptospirosis by polymerase chain reaction. Eighty (35.4%) of 226 patients had ≥ 1 positive serology, diagnostic for 15 rickettsial and 9 dengue cases. Acid-fast bacilli-positive sputum was obtained from three patients. Most common confirmed (81 of 226, 35.8%)/suspected diagnoses were typhoid fever (n = 41), pneumonia (n = 29), leptospirosis (n = 28), urinary tract infections (n = 20), rickettsioses (n = 19), dengue (n = 17), and meningitis/encephalitis (n = 15). There were 17 deaths, 7 (46.7%) were caused by meningitis/encephalitis. Multiple positive serologic results and few confirmed diagnoses indicate the need for improved diagnostics.  相似文献   
953.
954.
955.
For patients with rheumatoid arthritis (RA), remission can be achieved with tight control of inflammation and early use of disease modifying agents. The importance of remission as an outcome has been recently highlighted by European League Against Rheumatism recommendations. However, remission when defined by clinical remission criteria (disease activity score, simplified disease activity index, etc) does not always equate to the complete absence of inflammation as measured by new sensitive imaging techniques such as ultrasound (US) . There is evidence that imaging synovitis is frequently found in these patients and associated with adverse clinical and functional outcomes. This article reviews the data regarding remission, ultrasound imaging and outcomes in patients with RA to provide the background to a consensus statement from an international collaboration of ultrasonographers and rheumatologists who have recently formed a research network--the Targeted Ultrasound Initiative (TUI) group. The statement proposes that targeting therapy to PD activity provides superior outcomes compared with treating to clinical targets alone and introduces the rationale for a new randomised trial using targeted ultrasound in RA.  相似文献   
956.
957.
J Oral Pathol Med (2012) 41 : 119–123 Objective: ‘Field cancerization’ is an accepted model for oral carcinogenesis. So far, genetically altered fields have been just reported in the presence of carcinomas. This study assessed the distant mirror fields (MFs) of oral precancer by DNA high‐resolution flow cytometry (hr DNA‐FCM) and array‐Comparative Genomic Hybridization (a‐CGH). Methods: Five leukoplakias without dysplasia (OLs), seven dysplastic leukoplakias (DOLs), and 12 corresponding visually normal and non‐dysplastic MFs were analyzed. DNA aneuploidy (DNA Index, DI ≠ 1) was detected by hr DNA‐FCM on DAPI stained nuclei suspensions. The epithelial DNA aneuploid subclones were FCM‐sorted to obtain genomic DNA for a‐CGH. Results: Mirror fields, OLs, and DOLs showed increasing prevalence of DNA aneuploidy of, respectively, 8%, 20%, and 57%. The average number of chromosome aberrations (Ch‐Abs) was 2.8 in MFs, 3 in OLs, and 10.6 in DOLs. MFs relative to OLs and DOLs had average numbers of Ch‐Abs, respectively, of 1.8 and 3.6. Ch‐Abs were also observed in DNA diploid sublines, and often the same aberrations were observed in both MFs and corresponding OLs/DOLs. Conclusion: DNA aneuploidy and Ch‐Abs in MFs, the last ones being mainly gains, indicate an early onset of field effect in oral carcinogenesis.  相似文献   
958.
959.
Stroke is the most common cardiovascular disorder after heart disease, with a high mortality and often poor quality of life in survivors. Atrial fibrillation (AF), the most commonly occurring sustained cardiac arrhythmia increases the risk of stroke by five. However, stroke risk is not homogeneous and varies with associated morbidities and risk factors. Risk assessment scores have been developed and according to the calculated level of risk, guidelines recommend treatment with antithrombotic agents, preferably vitamin K antagonists (VKA). Despite these recommendations many patients with AF do not receive adequate thromboprophylaxis. The presence of AF is often not recognized and VKA are underused due to doctor- or patient-related factors and intrinsic disadvantages of these drugs. An awareness campaign for the diagnosis of AF is warranted, highlighting the risk of stroke. Novel anticoagulants that largely overcome many of the limitations of vitamin K antagonists are becoming available.  相似文献   
960.
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