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   16404篇
  免费   809篇
  国内免费   344篇
耳鼻咽喉   137篇
儿科学   460篇
妇产科学   272篇
基础医学   1527篇
口腔科学   352篇
临床医学   1657篇
内科学   2520篇
皮肤病学   123篇
神经病学   1018篇
特种医学   483篇
外国民族医学   1篇
外科学   1572篇
综合类   2378篇
预防医学   1987篇
眼科学   291篇
药学   1261篇
  10篇
中国医学   516篇
肿瘤学   992篇
  2024年   9篇
  2023年   285篇
  2022年   642篇
  2021年   795篇
  2020年   698篇
  2019年   602篇
  2018年   660篇
  2017年   523篇
  2016年   576篇
  2015年   559篇
  2014年   1237篇
  2013年   1204篇
  2012年   985篇
  2011年   1092篇
  2010年   848篇
  2009年   812篇
  2008年   786篇
  2007年   750篇
  2006年   651篇
  2005年   518篇
  2004年   440篇
  2003年   333篇
  2002年   298篇
  2001年   235篇
  2000年   263篇
  1999年   220篇
  1998年   159篇
  1997年   146篇
  1996年   160篇
  1995年   131篇
  1994年   134篇
  1993年   101篇
  1992年   86篇
  1991年   80篇
  1990年   68篇
  1989年   67篇
  1988年   71篇
  1987年   43篇
  1986年   35篇
  1985年   49篇
  1984年   35篇
  1983年   21篇
  1982年   33篇
  1981年   10篇
  1980年   25篇
  1979年   20篇
  1978年   17篇
  1977年   9篇
  1976年   6篇
  1974年   6篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease worldwide, with rising rates in parallel to those of obesity, type 2 diabetes, and metabolic syndrome. NAFLD encompasses a wide spectrum of pathology from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis, which are linked to poor outcomes. Studies confirm a significant amount of undiagnosed NAFLD and related fibrosis within the community, increasing the overall burden of the disease. NAFLD appears to be more prevalent in certain populations, such as those with type 2 diabetes and metabolic syndrome. Early detection and lifestyle modifications, including weight loss and regular exercise, have been shown to improve outcomes. Adverse cardiovascular events are a key contributor to NAFLD-associated morbidity and mortality, and efforts to minimize their occurrence are essential. A targeted and algorithmic approach using noninvasive diagnostic techniques is promptly required to identify and risk-stratify patients with NAFLD. Patients at low risk of progression to NASH and advanced fibrosis can be managed in the primary care setting, while those at high risk of disease progression should be referred to hepatology specialists for surveillance and treatment. This review summarizes the key data of NAFLD's impact within primary care populations and proposes a potential algorithmic approach to identifying and managing such patients.  相似文献   
33.
ObjectiveTo explore the analgesic effects and uterine hemodynamics of perpendicular needling (PN) and transverse needling (TN) at SP 6 in patients with primary dysmenorrhea (PD).MethodsIn this randomized controlled trial, patients with PD diagnosed with cold-dampness congealing pattern were randomly assigned in a ratio of 1:1 to receive PN or TN at bilateral SP 6 for 10 min. Acupuncture was performed when the menstrual pain score was over 40 mm on the first day of menstruation, as measured using the visual analog scale for pain (VAS-P). The primary outcome was average menstrual pain (VAS-P). Secondary outcomes included the pulsatility index (PI), resistance index (RI), and systolic-diastolic peaks ratio (S/D) in uterine arteries as measured using color Doppler ultrasonography; anxiety as assessed using the Hamilton Anxiety Rating Scale (HAMA), blood pressure (BP), and heart rate (HR).ResultsForty-eight patients completed the study. The TN group exhibited a significant reduction in VAS-P scores (–5.71 mm, 95% confidence interval (CI): –8.78, –2.63, P = .001), RI values (–0.05, 95% CI: –0.09, –0.01, P = .015), and HAMA values (–2.50, 95% CI: –4.78, –0.22, P = .032) when compared with the PN group. No significant differences in PI, S/D, BP, or HR values were observed between the two groups (P > .05).ConclusionTN at SP 6 was superior to PN in alleviating menstrual pain and anxiety in patients with PD. This analgesic effect of TN may be due to its better ability to improve uterine arterial blood flow via decreases in RI values.  相似文献   
34.
35.
36.
BackgroundPersons with Parkinson’s disease exhibit gait deficits during comfortable-pace overground walking and data from pressure sensitive mats have been used to quantify gait performance. The Primary Gait Screen is a new assessment which includes gait initiation, overground walking, turning, and gait termination. Although overground assessments are useful, the Primary Gait Screen offers a more complex evaluation than traditional gait assessments.Research questionIs the overground walking portion of the Primary Gait Screen comparable to traditional gait assessments?MethodsPersons with Parkinson’s disease (N = 175; 47 F, 128 M; 67 ± 9 yrs) prospectively completed 4 passes at a self-selected speed and two trials of the Primary Gait Screen on an 8 m long pressure-sensing mat. Spatiotemporal gait variables were computed and a repeated-measures MANOVA with a Bonferroni correction compared the spatiotemporal variables from the Primary Gait Screen to the self-selected trials: gait velocity, cadence, step length, step time, and stride length.ResultsThe analyses failed to detect differences between the Primary Gait Screen and self-selected trials for gait velocity, step length, or stride length (p > .01). Post-hoc tests revealed decreased cadence and increased step time were the only differences between the Primary Gait Screen trials and the self-selected trial (p < .001).SignificanceDifferences seen in cadence and step time during the Primary Gait Screen may be attributed to patients’ strategy, but are likely not clinically meaningful. The Primary Gait Screen appears to be a comparable assessment of overground walking in persons with Parkinson’s disease, and may be a useful and accurate clinical assessment of walking.  相似文献   
37.
38.
39.
40.
Background and objectivesPatients older than 75 years with ST-segment elevation myocardial infarction undergoing primary angioplasty in cardiogenic shock have high mortality. Identification of preprocedural predictors of short- and long-term mortality could be useful to guide decision-making and further interventions.MethodsWe analyzed a nationwide registry of primary angioplasty in the elderly (ESTROFA MI + 75) comprising 3576 patients. The characteristics and outcomes of the subgroup of patients in cardiogenic shock were analyzed to identify associated factors and prognostic predictors in order to derive a baseline risk prediction score for 1-year mortality. The score was validated in an independent cohort.ResultsA total of 332 patients were included. Baseline independent predictors of mortality were anterior myocardial infarction (HR 2.8, 95%CI, 1.4-6.0; P = .005), ejection fraction < 40% (HR 2.3, 95%CI, 1.14-4.50; P = .018), and time from symptom onset to angioplasty > 6 hours (HR 3.2, 95%CI, 1.6-7.5; P = .001). A score was designed that included these predictive factors (score “6-ANT-40”). Survival at 1 year was 54.5% for patients with score 0, 32.3% for score 1, 27.4% for score 2 and 17% for score 3 (P = .004, c-statistic 0.70). The score was validated in an independent cohort of 124 patients, showing 1-year survival rates of 64.5%, 40.0%, 28.9%, and 22.2%, respectively (P = .008, c-statistic 0.68).ConclusionsA preprocedural score based on 3 simple clinical variables (anterior location, ejection fraction < 40%, and delay time > 6 hours) may be used to estimate survival after primary angioplasty in elderly patients with cardiogenic shock and to guide preinterventional decision-making.  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