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   20498篇
  免费   997篇
  国内免费   108篇
耳鼻咽喉   148篇
儿科学   284篇
妇产科学   362篇
基础医学   2651篇
口腔科学   501篇
临床医学   1259篇
内科学   5247篇
皮肤病学   297篇
神经病学   1718篇
特种医学   882篇
外科学   3252篇
综合类   90篇
一般理论   1篇
预防医学   550篇
眼科学   558篇
药学   1517篇
中国医学   67篇
肿瘤学   2219篇
  2023年   87篇
  2021年   281篇
  2020年   242篇
  2019年   273篇
  2018年   336篇
  2017年   258篇
  2016年   357篇
  2015年   355篇
  2014年   478篇
  2013年   596篇
  2012年   947篇
  2011年   1000篇
  2010年   566篇
  2009年   477篇
  2008年   886篇
  2007年   921篇
  2006年   847篇
  2005年   887篇
  2004年   963篇
  2003年   865篇
  2002年   899篇
  2001年   817篇
  2000年   848篇
  1999年   755篇
  1998年   247篇
  1997年   192篇
  1996年   156篇
  1995年   166篇
  1994年   174篇
  1993年   149篇
  1992年   548篇
  1991年   469篇
  1990年   473篇
  1989年   477篇
  1988年   418篇
  1987年   357篇
  1986年   354篇
  1985年   351篇
  1984年   243篇
  1983年   181篇
  1982年   89篇
  1979年   172篇
  1978年   124篇
  1977年   117篇
  1974年   92篇
  1972年   89篇
  1971年   95篇
  1970年   84篇
  1968年   94篇
  1967年   92篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
2.
3.
4.
Cancer Chemotherapy and Pharmacology - Cancers are methionine (MET) and methylation addicted, causing them to be highly sensitive to MET restriction. The present study determined the efficacy of...  相似文献   
5.
6.
7.
8.
Health and logistical needs in emergencies have been well recognised. The last 7 years has witnessed improved professionalisation and standardisation of care for disaster affected communities – led in part by the World Health Organisation Emergency Medical Team (EMT) initiative.Mass casualty incidents (MCIs) resulting in burn injuries present unique challenges. Burn management benefits from specialist skills, expert knowledge, and timely availability of specialist resources. With burn MCIs occurring globally, and wide variance in existing burn care capacity, the need to strengthen burn care capability is evident. Although some high-income countries have well-established disaster management plans, including burn specific plans, many do not – the majority of countries where burn mass casualty events occur are without such established plans. Developing globally relevant recommendations is a first step in addressing this deficit and increasing preparedness to deal with such disasters.Global burn experts were invited to a succession of Technical Working Group on burns (TWGB) meetings to:1) review literature on burn care in MCIs; and2) define and agree on recommendations for burn care in MCIs.The resulting 22 recommendations provide a framework to guide national and international specialist burn teams and health facilities to support delivery of safe care and improved outcomes to burn patients in MCIs.  相似文献   
9.

Purpose

To evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney.

Materials and Methods

Between June 2016 and September 2017 at our institution, 12 inoperable patients underwent 15 cryoablation sessions for 17 small renal tumors. Of these, 9 patients who underwent 11 sessions of cryoablation were the focus of this study. For those patients, time-dependent changes in postoperative renal function were investigated by a retrospective review of clinical records. Evaluated were the estimated glomerular filtration rate (eGFR) and scintigraphy using 99m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before and 1 week, 1–2 months, and more than 6 months after cryoablation.

Results

Mean baseline eGFR was 76.88 ± 29.82 mL/min/1.73 m2 (mean ± standard deviation; range, 23.4–112.5). Mean eGFR 1 week, 1–2 months, and more than 6 months after cryoablation were 74.56 ± 26.68 mL/min/1.73 m2 (21.0–101.1), 69.5 ± 25.28 mL/min/1.73 m2 (24.1–105.6), and 75.08 ± 26.25 mL/min/1.73 m2 (29.0–107.3), respectively. Changes were statistically insignificant (P = .6044, P = .6699, and P = .9038, respectively). Regarding split renal function, the mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 47.27% ± 6.14 (38.8%–57.0%). Mean contributions of the affected kidney 1 week after, 1–2 months after, and more than 6 months after cryoablation were 44.40% ± 5.37 (38.3%–53.6%), 44.57% ± 6.52 (34.35%–55.0%), and 45.41% ± 7.77 (34.4%–56.5%), respectively. Differences from baseline were significant for the earliest 2 periods (P = .0473 and P = .0334, respectively) but not the later period (P = .2532).

Conclusions

Results suggested that total renal function does not worsen after cryoablation; however, function of the affected kidney worsened after cryoablation but later partially recovered.  相似文献   
10.
BackgroundThe onset of carious lesions and periodontal disease originates in plaque formed from dental bacteria. Appropriate plaque control is therefore important. Dental floss is one instrument used to control plaque. The influence of guardians is an important factor in whether children use dental floss regularly. However, the use of dental floss among school-age children and the relationship between use and family background has yet to be examined.AimIn this study, we conducted a questionnaire survey to examine rates of dental floss use and other related factors among elementary school children and their guardians.MethodsSurveys were sent to 298 guardians of children in grades 1–6 at an elementary school in Japan and 283 valid responses were received. Statistical analyses were carried out, with child’s use of dental floss as a dependent variable and grade, sex, guardian assistance with child's tooth brushing, frequency of child’s dental check-ups, and guardian's use of dental floss as independent variables.ResultsThe results revealed that 18.4% of children used dental floss compared with 52.7% of guardians, suggesting that the rate of usage among children is much lower than that among guardians. Logistic regression analysis further revealed that guardian's use of dental floss was significantly related to dental floss use among children.ConclusionThe guardian's use of dental floss was associated with dental floss use among their children in this group of Japanese elementary school.  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