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   2064篇
  免费   128篇
  国内免费   8篇
耳鼻咽喉   16篇
儿科学   51篇
妇产科学   60篇
基础医学   405篇
口腔科学   49篇
临床医学   142篇
内科学   347篇
皮肤病学   63篇
神经病学   349篇
特种医学   27篇
外科学   208篇
综合类   6篇
预防医学   122篇
眼科学   25篇
药学   137篇
中国医学   9篇
肿瘤学   184篇
  2023年   15篇
  2022年   36篇
  2021年   73篇
  2020年   41篇
  2019年   51篇
  2018年   51篇
  2017年   40篇
  2016年   55篇
  2015年   63篇
  2014年   93篇
  2013年   116篇
  2012年   171篇
  2011年   179篇
  2010年   96篇
  2009年   83篇
  2008年   137篇
  2007年   119篇
  2006年   133篇
  2005年   122篇
  2004年   118篇
  2003年   93篇
  2002年   97篇
  2001年   15篇
  2000年   9篇
  1999年   18篇
  1998年   22篇
  1997年   15篇
  1996年   13篇
  1995年   13篇
  1994年   11篇
  1993年   12篇
  1992年   6篇
  1991年   7篇
  1990年   5篇
  1989年   4篇
  1988年   10篇
  1987年   6篇
  1986年   7篇
  1985年   6篇
  1984年   3篇
  1983年   5篇
  1982年   6篇
  1980年   5篇
  1979年   4篇
  1977年   3篇
  1976年   2篇
  1974年   3篇
  1971年   1篇
  1966年   2篇
  1928年   1篇
排序方式: 共有2200条查询结果,搜索用时 15 毫秒
41.
Silicosis is a typical occupational disease, although some cases caused by non-industrial exposure have also been reported. We saw a 53-year-old male gardener with recurrent non-productive cough. A routine radiograph of the chest showed bilateral pulmonary nodules and subsequent computed tomography suggested that the infiltrates could be metastases. Open lung biopsy revealed nodules consisting of fibrotic tissue while the presence of birefringent silica particles was observed by polarised light microscopy. Mineralogical analysis of the substrata from the patient's workplace revealed an SiO(2) concentration of 31%. This case indicates that the inhalation of siliceous particles in a closed environment such as a greenhouse is a risk factor for silicosis.  相似文献   
42.
43.
Granulocyte colony-stimulating factor (G-CSF)-induced alteration of phosphoprotein during differentiation of HL-60 cells was studied. From the two-dimensional gel electrophoresis analysis of phosphoproteins, a 45 kD phosphoprotein in the cytosolic fraction of DMSO-pretreated HL-60 cells was rapidly dephosphorylated by the addition of G-CSF. This 45 kD phosphoprotein migrated into four or five spots between 4.5 and 5.5 pI. The dephosphorylation of 45 kD protein was observed within at least 10 min and reached a maximum at 60 min. Phosphoamino acid analysis showed that only serine residue of 45 kD phosphoprotein was phosphorylated, suggesting that G-CSF induced an activation of serine phosphatase. Furthermore, Staurosporine and calphostin C inhibited the phosphorylation of 45 kD protein, suggesting that protein kinase C or its downstream kinase(s) is involved in the phosphorylation of 45 kD protein. These results indicate that G-CSF causes dephosphorylation of a 45 kD cytosolic phosphoprotein which may play a role in signal transduction of G-CSF.  相似文献   
44.
In this study we report the long-term follow-up of EA, a patient originally affected by a disproportionate semantic impairment of biological categories due to herpetic encephalitis. After 10 years, EA still presented a biological categories semantic impairment, but his deficit had become minimal for animals while it remained considerably severe for fruit and vegetables, without any evolution from the original level of impairment. The eventual discrepancy between the two subsets of biological categories was statistically significant at word–picture matching and verbal semantic probes (and could not be explained by nuisance variables), but not significant at picture naming due to an associated lexical impairment that, besides plant life items, also affected animals and artefact stimuli.

Our recovery data corroborate the notion that biological categories should be further fractionated, and we comment on the suitability of different accounts of category specificity to accommodate such findings. We discuss our case against the background of other cases reported in the literature and the current models of organisation of the semantic system, bringing to light some interesting consistencies concerning patients whose semantic impairment disproportionately affects the categories of fruit and vegetables.  相似文献   
45.
The aim was to assess 3-year longitudinal data using 6MWT in 26 ambulant boys affected by DMD carrying nonsense mutations and to compare their results to other small mutations. We also wished to establish, within the nonsense mutations group, patterns of change according to several variables. Patients with nonsense mutations were categorized according to the stop codon type newly created by the mutation and also including the adjacent 5′ (upstream) and 3′ (downstream) nucleotides. No significant difference was found between nonsense mutations and other small mutations (p > 0.05) on the 6MWT. Within the nonsense mutations group, there was no difference in 6MWT when the patients were subdivided according to: Type of stop codon, frame status of exons involved, protein domain affected. In contrast, there was a difference when the stop codon together with the 3′ adjacent nucleotide (“stop+4 model”) was considered (p < 0.05) with patients with stop codon TGA and 3′ adjacent nucleotide G (TGAG) having a more rapid decline. Our finding suggest that the stop+4 model may help in predicting functional changes. This data will be useful at the time of interpreting the long term follow up of patients treated with Ataluren that are becoming increasingly available.  相似文献   
46.
Journal of NeuroVirology - There are over 3 million people in sub-Saharan Africa (SSA) aged 50 and over living with HIV. HIV and combined antiretroviral therapy (cART) exposure may accelerate the...  相似文献   
47.
48.
49.
Pain assessment that fully represents patients’ pain experiences is essential for chronic pain research and management. The traditional primary outcome measure has been a patient's average pain intensity over a time period. In this series of 3 articles, we examine whether pain assessment can be enhanced by considering additional outcome measures capturing temporal aspects of pain, such as pain maxima, duration, and variability. Ecological momentary assessment makes the assessment of such indices readily available. In this first article, we discuss the rationale for considering additional pain indices derived from ecological momentary assessment and examine which are most important to stakeholders. Patients (n = 32), clinicians (n = 20), and clinical trialists (n = 20) were interviewed about their preference rankings for Average, Worst, and Least Pain, Time in High Pain, Time in No/Low Pain, Pain Variability, and Pain Unpredictability. Each stakeholder group displayed a distinct preference hierarchy for different indices, and there were few commonalities between groups. Patients favored Worst Pain and Time in High Pain, followed by Pain Variability and Unpredictability. Trialists favored Average Pain, whereas clinicians favored Worst Pain. Results suggest that multiple temporal aspects of pain are relevant for stakeholders and should be considered when evaluating the efficacy of pain management.PerspectiveExamining which aspects of pain are most important to measure from the perspective of different stakeholders can facilitate efforts to include all relevant treatment outcomes. Our study suggests that multiple temporal aspects of pain intensity are important to stakeholders. This should be considered when evaluating the efficacy of pain management.  相似文献   
50.
Pain intensity is a complex and dynamic experience. A focus on assessing patients’ average pain levels may miss important aspects of pain that impact functioning in daily life. In this second of 3 articles investigating alternative indices of pain intensity derived from Ecological Momentary Assessments (EMA), we examine the indices’ associations with physical and psychosocial functioning. EMA data from 10 studies (2,660 patients) were reanalyzed to construct indices of Average Pain, Maximum Pain, Minimum Pain, Pain Variability, Time in High Pain, Time in Low Pain, Pain after Wake-up. Three sets of individual patient data meta-analyses examined 1) the test-retest reliability of the pain indices, 2) their convergent validity in relation to physical functioning, fatigue, depression, mental health, and social functioning, and 3) the incremental validity of alternative indices above Average Pain. Reliabilities approaching or exceeding a level of .7 were observed for all indices, and most correlated significantly with all functioning domains, with small to medium effect sizes. Controlling for Average Pain, Maximum Pain and Pain Variability uniquely predicted all functioning measures, and Time in High Pain predicted physical and social functioning. We suggest that alternative pain indices can provide new perspectives for understanding functioning in chronic pain.PerspectiveAlternative summary measures of pain intensity derived from EMA have the potential to help better understand patients’ pain experience. Utilizing EMA for the assessment of Maximum Pain, Pain Variability, and Time in High Pain may provide an enhanced window into the relationships between pain and patients’ physical and psychosocial functioning.  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