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   18012篇
  免费   1069篇
  国内免费   136篇
耳鼻咽喉   228篇
儿科学   449篇
妇产科学   242篇
基础医学   2778篇
口腔科学   428篇
临床医学   1540篇
内科学   3720篇
皮肤病学   585篇
神经病学   1456篇
特种医学   759篇
外科学   2576篇
综合类   71篇
一般理论   2篇
预防医学   891篇
眼科学   411篇
药学   1507篇
中国医学   208篇
肿瘤学   1366篇
  2023年   129篇
  2022年   352篇
  2021年   608篇
  2020年   336篇
  2019年   458篇
  2018年   532篇
  2017年   430篇
  2016年   586篇
  2015年   780篇
  2014年   901篇
  2013年   993篇
  2012年   1550篇
  2011年   1426篇
  2010年   865篇
  2009年   752篇
  2008年   1017篇
  2007年   1041篇
  2006年   927篇
  2005年   855篇
  2004年   719篇
  2003年   606篇
  2002年   565篇
  2001年   389篇
  2000年   393篇
  1999年   297篇
  1998年   103篇
  1997年   80篇
  1996年   61篇
  1995年   69篇
  1994年   41篇
  1993年   36篇
  1992年   119篇
  1991年   95篇
  1990年   115篇
  1989年   80篇
  1988年   89篇
  1987年   68篇
  1986年   64篇
  1985年   61篇
  1984年   45篇
  1983年   44篇
  1981年   32篇
  1979年   42篇
  1978年   56篇
  1977年   37篇
  1976年   30篇
  1975年   38篇
  1974年   32篇
  1969年   25篇
  1968年   24篇
排序方式: 共有10000条查询结果,搜索用时 131 毫秒
1.
Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960–0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0–98.1%) and 90.9% (86.0–94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule.  相似文献   
2.
This retrospective study aimed to evaluate radiation-induced pneumonitis (RIP) and a related condition that we define in this report—prolonged minimal RIP (pmRIP)—after stereotactic body radiotherapy (SBRT) for Stage I primary lung cancer in patients with chronic obstructive pulmonary disease (COPD). We assessed 136 Stage I lung cancer patients with COPD who underwent SBRT. Airflow limitation on spirometry was classified into four Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades, with minor modifications: GOLD 1 (mild), GOLD 2 (moderate), GOLD 3 (severe) and GOLD 4 (very severe). On this basis, we defined two subgroups: COPD-free (COPD −) and COPD-positive (COPD +). There was no significant difference in overall survival or cause-specific–survival between these groups. Of the 136 patients, 44 (32%) had pmRIP. Multivariate analysis showed that COPD and the Brinkman index were statistically significant risk factors for the development of pmRIP. COPD and the Brinkman index were predictive factors for pmRIP, although our findings also indicate that SBRT can be tolerated in early lung cancer patients with COPD.  相似文献   
3.
4.
5.

Background

Many patients undergoing below knee amputations (BKA) return for subsequent unplanned operations, hospital readmission, or postoperative complications. This unplanned medical management negatively impacts both patient outcomes and our healthcare system. This study primarily investigates the risk factors for unplanned reoperation following BKA.

Methods

Below knee amputations from the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database from the years 2012–2014 were identified by CPT code 27880 for amputation through the tibia and fibula. Our query identified 4631 BKA cases, including 30 day complications. Multivariate logistic regression modeling was performed on several patient demographic and disease factors to assess for independent predictors of unplanned reoperation. Secondary outcomes of unplanned and related readmissions (related to the procedure), major complications, minor complications, and mortality were also included in the analysis.

Results

Of 4631 BKAs identified, 9.63% (446/4631) underwent unplanned reoperations and 8.75% (405/4631) had unplanned and related readmissions. Major complications were experienced by 12.8% (593/4631) and minor complications by 8.7% (401/4631). Thirty day mortality rate was 5.14% (238/4631). The most common procedures for unplanned operations were thigh amputations (128/446, 28.7%), debridement/secondary closure (114/446, 25.6%), and revision leg amputations (46/446, 10.32%). Factors associated with an increased risk of unplanned reoperation included patients transferred from another facility (Adjusted Odds Ratio [AOR]?=?1.28; p?=?.04), recent smokers (AOR?=?1.34; p?=?.02), bleeding disorder (AOR?=?1.30; p?=?.02), and preoperative ventilator use (AOR?=?2.38; p?=?.01).

Conclusion

Patients that were ongoing/recent smokers, had diagnosed bleeding disorders, required preoperative ventilator use, or were transferred in from another facility were associated with the highest risks of reoperation following BKA. This patient population experiences high rates of reoperation, readmission, complication, and mortality.  相似文献   
6.
7.
8.
9.

Objective

To explore from a gender perspective the association with subjective health of the interaction between education and household arrangements within the framework of social determinants of health placed at the micro and mezzo levels.

Methods

The data comes from the Spanish sample of the European Union Statistics on Income and Living Conditions for 2014. Independent logistic regression models for men and women were run to analyze the association with subjective health of the interaction between education and household arrangements. An additive model was run to assess possible advantages over the interaction approach.

Results

The interaction models show a lower or even no significant effect on health of household arrangements usually negatively associated with health among individuals with high education, displaying specific patterns according to sex.

Conclusions

Health profiles of women and men are more precisely drawn if both social determinants of health are combined. Among the women, the important role was confirmed of both social determinants of health in understanding their health inequalities. Among the men, mainly those with low educational achievement, the interaction revealed that the household was a more meaningful social determinant of health. This could enable the definition of more efficient public policies to reduce health and gender inequalities.  相似文献   
10.
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