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   4887篇
  免费   233篇
  国内免费   22篇
耳鼻咽喉   40篇
儿科学   169篇
妇产科学   238篇
基础医学   554篇
口腔科学   144篇
临床医学   409篇
内科学   1138篇
皮肤病学   72篇
神经病学   332篇
特种医学   161篇
外科学   625篇
综合类   21篇
一般理论   2篇
预防医学   248篇
眼科学   33篇
药学   366篇
中国医学   11篇
肿瘤学   579篇
  2023年   21篇
  2022年   74篇
  2021年   126篇
  2020年   64篇
  2019年   104篇
  2018年   132篇
  2017年   88篇
  2016年   92篇
  2015年   110篇
  2014年   142篇
  2013年   195篇
  2012年   303篇
  2011年   301篇
  2010年   163篇
  2009年   129篇
  2008年   238篇
  2007年   254篇
  2006年   230篇
  2005年   264篇
  2004年   222篇
  2003年   255篇
  2002年   177篇
  2001年   123篇
  2000年   154篇
  1999年   143篇
  1998年   60篇
  1997年   34篇
  1996年   33篇
  1995年   31篇
  1994年   30篇
  1993年   26篇
  1992年   74篇
  1991年   78篇
  1990年   70篇
  1989年   64篇
  1988年   67篇
  1987年   68篇
  1986年   65篇
  1985年   61篇
  1984年   43篇
  1983年   42篇
  1982年   16篇
  1981年   19篇
  1980年   14篇
  1979年   30篇
  1978年   20篇
  1976年   9篇
  1975年   15篇
  1973年   13篇
  1972年   8篇
排序方式: 共有5142条查询结果,搜索用时 15 毫秒
91.
During the last 15 years we have witnessed an unprecedented expansion in the drugs developed to target human epidermal growth factor receptor-2 (HER-2) positive breast cancer. Trastuzumab, pertuzumab, ado-trastuzumab emtansine and lapatinib are currently food and drug administration (FDA)-approved for the treatment of breast cancer patients with HER-2 over-expressed. However, given the amount of information gathered from years of uninterrupted clinical research, it is essential to have periodic updates that succinctly recapitulate what we have learnt over these last years and help us to apply that information in our daily practice. This review will pursue that objective. We will summarize the most relevant and updated information related to the state of the art management of HER-2 positive breast cancer in all the clinical scenarios including the adjuvant, neoadjuvant and metastatic settings. But we will also critically appraise that literature in order to highlight some key clinical concepts that should not be overlooked. Lastly, this review will also point out some of the most promising strategies that are currently being tested and may soon become available.  相似文献   
92.
93.
Thirty years ago, the type 1 ribosome-inactivating protein (RIP) saporin-S6 (also known as saporin) was isolated from Saponaria officinalis L. seeds. Since then, the properties and mechanisms of action of saporin-S6 have been well characterized, and it has been widely employed in the construction of conjugates and immunotoxins for different purposes. These immunotoxins have shown many interesting results when used in cancer therapy, particularly in hematological tumors. The high enzymatic activity, stability and resistance to conjugation procedures and blood proteases make saporin-S6 a very useful tool in cancer therapy. High efficacy has been reported in clinical trials with saporin-S6-containing immunotoxins, at dosages that induced only mild and transient side effects, which were mainly fever, myalgias, hepatotoxicity, thrombocytopenia and vascular leak syndrome. Moreover, saporin-S6 triggers multiple cell death pathways, rendering impossible the selection of RIP-resistant mutants. In this review, some aspects of saporin-S6, such as the chemico-physical characteristics, the structural properties, its endocytosis, its intracellular routing and the pathogenetic mechanisms of the cell damage, are reported. In addition, the recent progress and developments of saporin-S6-containing immunotoxins in cancer immunotherapy are summarized, including in vitro and in vivo pre-clinical studies and clinical trials.  相似文献   
94.
The removal of mycotoxins from contaminated feed using lactic acid bacteria (LAB) has been proposed as an inexpensive, safe, and promising mycotoxin decontamination strategy. In this study, viable and heat-inactivated L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T cells were investigated for their ability to remove aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEA), and deoxynivalenol (DON) from MRS medium and PBS buffer over a 24 h period at 37 °C. LAB decontamination activity was also assessed in a ZEA-contaminated liquid feed (LF). Residual mycotoxin concentrations were determined by UHPLC-FLD/DAD analysis. In PBS, viable L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T cells removed up to 57% and 30% of ZEA and DON, respectively, while AFB1 and OTA reductions were lower than 15%. In MRS, 28% and 33% of ZEA and AFB1 were removed, respectively; OTA and DON reductions were small (≤15%). Regardless of the medium, heat-inactivated cells produced significantly lower mycotoxin reductions than those obtained with viable cells. An adsorption mechanism was suggested to explain the reductions in AFB1 and OTA, while biodegradation could be responsible for the removal of ZEA and DON. Both viable LAB strains reduced ZEA by 23% in contaminated LF after 48 h of incubation. These findings suggest that LAB strains of L. acidophilus CIP 76.13T and L. delbrueckii subsp. bulgaricus CIP 101027T may be applied in the feed industry to reduce mycotoxin contamination.  相似文献   
95.
96.
The MiniMental Parkinson (MMP) has been derived from the MiniMental State Examination (MMSE) for the screening of cognitive impairment in Parkinson’s disease by adding subtests that were focused on executive and visuo-spatial impairment more than on memory or language deficits. In this multicenter study, the psychometric and validity properties of the MMP have been evaluated in 69 cognitively intact and 52 cognitively impaired patients with Parkinson’s disease, classified according to their performance at the Dementia Rating Scale. The MMP showed better metrics and convergent validity, and higher screening ability. However, its performance was not fully satisfying in terms of data distribution, coefficient of variation and specificity, and Receiver Operating Characteristic curves did not show clear cut superiority of either scale at their best sensitivity–specificity trade off. The MMP seems to be slightly preferable to the MMSE only at a cut off that favours sensitivity with respect to specificity, for screening purposes. The test is simple and quick, but has limitations in terms of validity.  相似文献   
97.
98.
BackgroundInfluenza is an important public health problem, with potential severe consequences among people with chronic diseases. The aim of this study was to obtain reliable measures of seasonal influenza vaccine uptake in this population, otherwise not available in Italy.MethodsProgressi delle Aziende Sanitarie per la Salute in Italia (PASSI) is a nationwide surveillance system of health-related behaviours and acceptance of preventive interventions (including influenza immunisation) offered by the Italian National Health Service. Data are collected with telephone interviews at local health unit level for supporting local activities. The survey sample is randomly selected from local health unit lists of adult residents. The trend of annual vaccine coverage since 2008 was estimated for people aged 18–64 years who reported having at least one chronic disease. To obtain a sufficient sample size in subgroups, we analysed the characteristics of vaccinated people in the 2010–13 cumulative dataset. Univariate, multivariate, and logistic regression analyses were undertaken.FindingsIn 2008–13, 13 659 individuals with at least one chronic disease were interviewed. Vaccination coverage fell significantly from 29·7% (95% CI 27·2–32·4) in 2007–08 to 19·9% (18·0–22·1) in 2012–13. During 2010–13, the overall proportion of vaccinated people with a chronic disease was 25·6% (24·5–26·7). Vaccine coverage of people with diabetes (34·3%, 31·7–36·9) or cardiovascular diseases (31·8%, 29·6–34·2) was greater than that of people affected by renal failure, respiratory diseases, tumours, or chronic liver diseases (26·5% [22·5–30·7], 24·9% [23·2–26·7], 22·2% [20·0–24·6], and 20·6% [17·5–24·6], respectively). Vaccination coverage increased with age (from 13·1% [11·0–15·5] in the 18–34 year age group to 33·4% [31·9–35·1] in people aged 50–64 years); it was higher among people with a low educational level than among those with a high educational level, higher in those having economic difficulties than in those with no economic difficulties, and higher among Italian citizens than among non-citizens.InterpretationIn the past few years, prevalence of influenza vaccination in Italian adults with at least one chronic disease was well below the Ministry of Health's goal (75% minimum) and showed a downward trend. A major reason of this evolution is probably the changing public perception of the benefits and risks of vaccines. PASSI is a source of useful data not otherwise available for public health intervention.FundingItalian Ministry of Health.  相似文献   
99.
100.
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