全文获取类型
收费全文 | 733418篇 |
免费 | 51323篇 |
国内免费 | 1439篇 |
专业分类
耳鼻咽喉 | 9557篇 |
儿科学 | 23803篇 |
妇产科学 | 18120篇 |
基础医学 | 114264篇 |
口腔科学 | 20960篇 |
临床医学 | 66018篇 |
内科学 | 141052篇 |
皮肤病学 | 16880篇 |
神经病学 | 51574篇 |
特种医学 | 26875篇 |
外国民族医学 | 76篇 |
外科学 | 109086篇 |
综合类 | 15020篇 |
现状与发展 | 2篇 |
一般理论 | 162篇 |
预防医学 | 52304篇 |
眼科学 | 16768篇 |
药学 | 55841篇 |
3篇 | |
中国医学 | 2399篇 |
肿瘤学 | 45416篇 |
出版年
2021年 | 6016篇 |
2019年 | 5842篇 |
2018年 | 8426篇 |
2017年 | 6511篇 |
2016年 | 7270篇 |
2015年 | 8072篇 |
2014年 | 10971篇 |
2013年 | 16153篇 |
2012年 | 21715篇 |
2011年 | 22811篇 |
2010年 | 13453篇 |
2009年 | 12607篇 |
2008年 | 21180篇 |
2007年 | 22770篇 |
2006年 | 23178篇 |
2005年 | 21745篇 |
2004年 | 21249篇 |
2003年 | 20144篇 |
2002年 | 19664篇 |
2001年 | 37232篇 |
2000年 | 37917篇 |
1999年 | 31301篇 |
1998年 | 8220篇 |
1997年 | 6902篇 |
1996年 | 7236篇 |
1995年 | 6871篇 |
1994年 | 6315篇 |
1992年 | 23578篇 |
1991年 | 23536篇 |
1990年 | 22853篇 |
1989年 | 22628篇 |
1988年 | 20559篇 |
1987年 | 19960篇 |
1986年 | 19013篇 |
1985年 | 17776篇 |
1984年 | 13040篇 |
1983年 | 11040篇 |
1982年 | 6066篇 |
1979年 | 11794篇 |
1978年 | 8315篇 |
1977年 | 6990篇 |
1976年 | 6696篇 |
1975年 | 7437篇 |
1974年 | 8694篇 |
1973年 | 8318篇 |
1972年 | 7834篇 |
1971年 | 7310篇 |
1970年 | 7059篇 |
1969年 | 6495篇 |
1968年 | 5927篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Adeline Tarantini Sylvie Huet Gérard Jarry Rachelle Lanceleur Martine Poul Ana Tavares Nádia Vital Henriqueta Louro Maria João Silva Valérie Fessard 《Environmental and molecular mutagenesis》2015,56(2):218-227
Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
92.
93.
A.C. Randag R. Graaff M.M. Dreise A. Vierkötter P.M.N. Werker M.W. Stenekes 《The British journal of dermatology》2015,173(5):1199-1204
94.
95.
96.
C. Banella M. Ginevrino G. Catalano E. Fabiani G. Falconi M. Divona P. Curzi P. Panetta M.T. Voso N.I. Noguera 《Hematology/oncology and stem cell therapy》2021,14(2):163-168
FGFR–TACC, found in different tumor types, is characterized by the fusion of a member of fibroblast grown factor receptor (FGFR) tyrosine kinase (TK) family to a member of the transforming acidic coiled-coil (TACC) proteins. Because chromosome numerical alterations, hallmarks of FGFR–TACC fusions are present in many hematological disorders and there are no data on the prevalence, we studied a series of patients with acute myeloid leukemia and myelodysplastic syndrome who presented numerical alterations using cytogenetic traditional analysis. None of the analyzed samples showed FGFR3–TACC3 gene fusion, so screening for this mutation at diagnosis is not recommended. 相似文献
97.
98.
99.
Bj?rn Stessel Audrey A. Fiddelers Elbert A. Joosten Daisy M.N. Hoofwijk Hans-Fritz Gramke Wolfgang F.F.A. Buhre 《Medicine》2015,94(39)
Traditionally, major complications and unanticipated admission/readmission rates were used to assess outcome after day surgery. However, in view of the relative absence of major complications the quality of recovery (QOR) should be considered one of the principal endpoints after day surgery. In our study, the level of QOR is defined by a combination of the Global Surgical Recovery (GSR) Index and the Quality of Life (QOL).The aim of this study was to analyze prevalence and predictors of QOR after day surgery on the fourth postoperative day.Elective patients scheduled for day surgery from November 2008 to April 2010 were enrolled in a prospective cohort study. Outcome parameters were measured by using questionnaire packages at 2 time points: 1 week preoperatively and 4 days postoperatively. Primary outcome parameter is the QOR and is defined as good if the GSR index >80% as well as the postoperative QOL is unchanged or improved as compared with baseline. QOR is defined as poor if both the GSR index ≤80% and if the postoperative QOL is decreased as compared with baseline. QOR is defined as intermediate in all other cases. Three logistic regression analyses were performed to determine predictors for poor QOR after day surgery.A total of 1118 patients were included. A good QOR was noted in 17.3% of patients, an intermediate QOR in 34.8%, and a poor QOR in 47.8% 4 days after day surgery. The best predictor for poor QOR after day surgery was type of surgery. Other predictors were younger age, work status, and longer duration of surgery. A history of previous surgery, expected pain (by the patient) and high long-term surgical fear were significant predictors of poor QOR in only 1 of 3 prediction models.The QOR at home 4 days after day surgery was poor in the majority of patients and showed a significant procedure-specific variation. Patients at risk for poor QOR can be identified during the preoperative period based on type of surgery, age, work status, and the duration of the surgery. 相似文献
100.