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   6019篇
  免费   334篇
  国内免费   30篇
耳鼻咽喉   107篇
儿科学   123篇
妇产科学   111篇
基础医学   820篇
口腔科学   488篇
临床医学   390篇
内科学   1394篇
皮肤病学   131篇
神经病学   590篇
特种医学   100篇
外科学   682篇
综合类   29篇
一般理论   1篇
预防医学   638篇
眼科学   64篇
药学   440篇
中国医学   75篇
肿瘤学   200篇
  2023年   57篇
  2022年   121篇
  2021年   212篇
  2020年   132篇
  2019年   166篇
  2018年   216篇
  2017年   137篇
  2016年   198篇
  2015年   194篇
  2014年   282篇
  2013年   326篇
  2012年   468篇
  2011年   512篇
  2010年   267篇
  2009年   182篇
  2008年   365篇
  2007年   332篇
  2006年   314篇
  2005年   263篇
  2004年   221篇
  2003年   186篇
  2002年   145篇
  2001年   141篇
  2000年   127篇
  1999年   103篇
  1998年   41篇
  1997年   33篇
  1996年   26篇
  1995年   32篇
  1994年   14篇
  1993年   18篇
  1992年   60篇
  1991年   59篇
  1990年   43篇
  1989年   51篇
  1988年   39篇
  1987年   35篇
  1986年   22篇
  1985年   28篇
  1984年   13篇
  1983年   17篇
  1978年   16篇
  1975年   16篇
  1974年   12篇
  1973年   15篇
  1971年   11篇
  1970年   11篇
  1969年   13篇
  1968年   16篇
  1967年   10篇
排序方式: 共有6383条查询结果,搜索用时 15 毫秒
71.
Carboplatin is commonly used to treat a variety of tumors. We investigated the effects of carboplatin (100 mg/kg) in the development and metastatic dissemination of the 4T1 mice mammary carcinoma. Carboplatin was able to reduce tumor volume and the number of lung metastases in 50% compared to the control animals. Mitotic and apoptotic indices were also decreased by the treatment. Assessment of the vascularization of the tumors revealed a significant decrease in blood vessel formation by carboplatin. A decrease in nuclear positivity of CDC47 and cyclin D1 was observed in the group treated with carboplatin when compared to the control group. Positivity for p53 was observed in the control group (2/28; 5%) and the treated group (5/71; 4%). Carboplatin has been demonstrated to be an efficient regulator of 4T1MMT growth and dissemination. The action of this chemotherapeutic agent seems to be related to the induction of apoptosis and inhibition of angiogenesis and cell proliferation.  相似文献   
72.
73.
74.
75.
76.
77.
ObjectiveTo identify the urban phlebotomine sandfly fauna in Ponta Porã, Mato Grosso do Sul State, Brazil.MethodsThe captures were undertaken from April 2009 to March 2010 with CDC light traps in 14 ecotopes (intra and peridomicile) in different areas of the city, Shannon traps being used in areas with abundant vegetation.ResultsA total of 707 specimens were captured with CDC light traps (565 males and 142 females) and 155 specimens (112 males and 43 females) with Shannon traps, a total of 862 phlebotomines. The specimens captured belonged to eight species: Lutzomyia longipalpis (Lutz & Neiva, 1912), Evandromyia cortelezzii (Brethes, 1923), Sciopemyia sordelli (Shannon & Del Ponte, 1927), Pintomyia pessoai (Coutinho & Barretto, 1940); Pintomyia monticola (Costa Lima, 1932); Brumptomyia brumpti (Larousse, 1920); Nyssomyia whitmani (Antunes & Coutinho, 1939) and Psathyromyia shannoni (Dyar, 1929). Lutzomyia longipalpis, the main vector of Leishmania (Leishmania) chagasi, was the species most frequently captured (97.03%) and also the most abundant according to the standardized abundance index (SAI)=0.86.ConclusionsThe highest species richness was captured, with CDC light traps, inside the domiciles and the species diversity and evenness in the peridomicile, clearly indicating a preference for anthropic environments.  相似文献   
78.
79.
80.
This study evaluated the effects of the isolated use of a low dose of methyltestosterone (MT) on cardiovascular reflexes and hormonal levels and its geno‐ and cytotoxic safety in ovariectomized rats. Female Wistar rats were divided into four groups (n = 6), respectively: SHAM (received vehicle methylcellulose 0.5%), SHAM + MT (received MT 0.05 mg/kg), OVX (received vehicle), and OVX + MT (received MT). Twenty‐one days after ovariectomy, treatment was given orally daily for 28 days. The Bezold–Jarisch reflex (BJR) was analyzed by measuring the bradycardic and hypotensive responses elicited by phenylbiguanide (PBG) administration. The baroreflex sensitivity (BRS) was evaluated by phenylephrine and sodium nitroprussite. Myocyte hypertrophy was determined by morphometric analysis of H&E stained slides. Biochemical data were analyzed, as well as micronucleus assay. MT improved BRS and increased testosterone values, but did not change estradiol in the OVX group. MT did not promote changes in mean arterial pressure, heart rate, BJR, serum concentrations of troponin I, weight and histopathology of the heart. MT was able to restore the BRS in OVX rats. The geno‐ and cytotoxic safety of the MT was demonstrated by the absence of an increase in the micronucleus (PCEMN) or change in the ratio between normochromatic erythrocytes and polychromatic erythrocytes (NCE/PCE).  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