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   4821篇
  免费   575篇
  国内免费   28篇
耳鼻咽喉   54篇
儿科学   144篇
妇产科学   57篇
基础医学   480篇
口腔科学   153篇
临床医学   610篇
内科学   1121篇
皮肤病学   156篇
神经病学   329篇
特种医学   221篇
外科学   763篇
综合类   155篇
现状与发展   30篇
一般理论   3篇
预防医学   517篇
眼科学   79篇
药学   217篇
中国医学   5篇
肿瘤学   330篇
  2023年   186篇
  2022年   32篇
  2021年   63篇
  2020年   94篇
  2019年   76篇
  2018年   119篇
  2017年   93篇
  2016年   84篇
  2015年   110篇
  2014年   164篇
  2013年   166篇
  2012年   233篇
  2011年   282篇
  2010年   164篇
  2009年   157篇
  2008年   179篇
  2007年   235篇
  2006年   204篇
  2005年   181篇
  2004年   165篇
  2003年   158篇
  2002年   183篇
  2001年   123篇
  2000年   119篇
  1999年   131篇
  1998年   86篇
  1997年   89篇
  1996年   72篇
  1995年   72篇
  1994年   62篇
  1993年   69篇
  1992年   81篇
  1991年   71篇
  1990年   77篇
  1989年   88篇
  1988年   85篇
  1987年   66篇
  1986年   58篇
  1985年   67篇
  1984年   51篇
  1983年   54篇
  1982年   35篇
  1981年   36篇
  1980年   38篇
  1979年   42篇
  1978年   29篇
  1977年   32篇
  1976年   38篇
  1975年   38篇
  1974年   29篇
排序方式: 共有5424条查询结果,搜索用时 15 毫秒
991.
Hyrtl's fissure     
Rich PM 《AJNR. American journal of neuroradiology》2006,27(7):1393; author reply 1393-1393; author reply 1394
  相似文献   
992.
For individuals with grapheme-colour synaesthesia, letters, numbers and words elicit vivid and highly consistent colour experiences. A critical question in determining the mechanisms underlying the phenomenon is whether synaesthetic colours arise early in visual processing, prior to the allocation of focused attention, or at some later stage following explicit recognition of the inducing form. If the synaesthetic colour elicited by an achromatic target emerges early in visual processing, then the target should be relatively easy to find in an array of achromatic distractor items, provided the target and distractors elicit different synaesthetic colours. Here we present data from 14 grapheme-colour synaesthetes and 14 matched non-synaesthetic controls, each of whom performed a visual search task in which a target digit was distinguished from surrounding distractors either by its unique synaesthetic colour or by its unique display colour. Participants searched displays of 8, 16 or 24 items for a specific target. In the chromatic condition, target and distractor digits were presented in different colours (e.g., a yellow '2' amongst blue '5's). In the achromatic condition, all digits in the display were black, but targets elicited a different synaesthetic colour from that induced by the distractors. Both synaesthetes and controls showed the expected efficient (pop-out) search slopes when the target was defined by a unique display colour. In contrast, search slopes for both groups were equally inefficient when the target and distractors were achromatic, despite eliciting distinct colours for the synaesthetes under normal viewing conditions. These results indicate that, at least for the majority of individuals, synaesthetic colours do not arise early enough in visual processing to guide or attract focal attention. Our findings are consistent with the hypothesis that graphemic inducers must be selectively attended to elicit their synaesthetic colours.  相似文献   
993.
Background Interleukin (IL)‐17A has major proinflammatory activity in psoriatic lesional skin. Objectives To assess the efficacy and safety of secukinumab, a fully human IgG1κ monoclonal anti‐IL‐17A antibody, in moderate‐to‐severe plaque psoriasis in a phase II regimen‐finding study. Methods A total of 404 patients were randomized to subcutaneous placebo (n = 67) or one of three secukinumab 150 mg induction regimens: single (week 0; n = 66), early (weeks 0, 1, 2, 4; n = 133) and monthly (weeks 0, 4, 8; n = 138 patients). The primary outcome was ≥ 75% improvement from baseline Psoriasis Area and Severity Index score (PASI 75) at week 12. PASI 75 responders from active treatment arms at week 12 were rerandomized to either a fixed‐interval (secukinumab 150 mg at weeks 12 and 24; n = 65) or a treatment‐at‐start‐of‐relapse maintenance regimen (secukinumab 150 mg at visits at which a start of relapse was observed; n = 67). Results At week 12, early and monthly induction regimens resulted in higher PASI 75 response rates vs. placebo (54·5% and 42·0% vs. 1·5%; P < 0·001 for both). Among PASI 75 responders at week 12 entering the maintenance period, PASI 75 and PASI 90 achievement at least once from week 20 to week 28 was superior with the fixed‐interval regimen [85% (n = 55) and 58% (n = 38), respectively] vs. the start‐of‐relapse regimen [67% (n = 45), P = 0·020, and 21% (n = 14), respectively]. Fifteen weeks after last study drug administration, < 10% of patients in the fixed‐interval and start‐of‐relapse groups experienced a start of relapse. No immunogenicity was observed, and no injection‐site reactions were reported. Reported cases of neutropenia were mild‐to‐moderate (≤ grade 2); none was associated with clinically significant adverse events or resulted in study discontinuation. Due to the brief duration of the safety assessment, no firm conclusions can be drawn regarding long‐term safety. Conclusions Secukinumab shows efficacy for induction and maintenance treatment of moderate‐to‐severe plaque psoriasis.  相似文献   
994.
995.
Rhinoresistometry and acoustic rhinometry are two established apparative methods to objectify the respiratory function of the nose. Both methods use different variables to describe nasal patency: “hydraulic diameter”, HD, in rhinoresistometry, and “minimal cross-sectional area”, MCA1 (nasal isthmus) and MCA2 (head of the inferior turbinate and cavernous body of the nasal septum), in acoustic rhinometry.ObjectiveThis study analyzes the mutual correlation of HD and MCA as a pilot study in patients without nasal pathologies. Additionally, we investigated if these objective variables correlate with the NOSE score, a validated tool to measure subjective perception of nasal patency.MethodPlanned data collection in a collective of 24 healthy subjects without nasal pathologies.ResultsStatistically significant, weak to moderate correlations were found between HD and MCA2 before decongestion. A moderate correlation was found between both HD and MCA2 and the NOSE score on the narrower side.ConclusionIn the assessment of nasal patency, it seems advisable to determine HD, MCA1 and MCA2, but also a subjective variable such as the NOSE score, which all seem to be not fully redundant variables. In further studies, the correlation of the variables should be assessed in patients with nasal pathologies.  相似文献   
996.
Abstract

Gay, bisexual, queer and other men who have sex with men are disproportionately affected by HIV in Canada. While up to 63% of transgender men identify as gay, bisexual or queer and report a variety of HIV sexual risk behaviours, transgender men are often overlooked within epidemiological HIV surveillance and research. While a growing body of research has begun to examine sexual risk for transgender gay, bisexual and queer men, most studies have been conducted in the USA. This study explored sexual HIV risk for this population in the Canadian context, specifically in British Columbia, in an environment of publically funded universal access to healthcare, including HIV testing and treatment. We conducted interviews with 11 gay, bisexual and queer transgender men. Participants’ narratives suggest that HIV risk for these transgender men is shaped by a diversity of sexual behaviours, including inconsistent condom use, seeking partners online for greater safety and accessing HIV/STI testing and other healthcare services despite facing transition-related barriers. Public health prevention and health education must recognise the presence of transgender men and ensure health services and broader population health promotion meet the unique sexual health needs of this sub-population of gay, bisexual and queer men.  相似文献   
997.
998.
999.
1000.
Marginal leakage in amalgam restorations often precedes the development of secondary caries. One potential way to improve the marginal seal of such restorations, and thus minimize the risk of carles development, is to apply a glassionomer base prior to amalgam placement.
This study compared microleakage resistance among amalgam restorations placed with and without light-cured glass-ionomer base materials. Preparations were made in extracted human molar teeth. Four groups were studied, including copal varnish, which was used as a control. All specimens were restored with amalgam. Results indicated significantly greater leakage at the cavity wall/base interface for restorations with a copal varnish cavity liner than for those with a glass-ionomer base. Leakage differences among bases were also found at the amalgam/base interface. Best results were obtained with a dual-cure resin-based system. These samples showed minimal leakage at both the cavity wall/base and the base/amalgam interfaces. These findings suggest that light-cured glass-ionomer bases can be effective in the prevention of microleakage in amalgam restorations.  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