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   906篇
  免费   82篇
耳鼻咽喉   19篇
儿科学   22篇
妇产科学   16篇
基础医学   107篇
口腔科学   36篇
临床医学   110篇
内科学   104篇
皮肤病学   24篇
神经病学   188篇
特种医学   22篇
外科学   109篇
综合类   14篇
预防医学   74篇
眼科学   8篇
药学   98篇
肿瘤学   37篇
  2022年   8篇
  2021年   23篇
  2020年   14篇
  2019年   17篇
  2018年   11篇
  2017年   16篇
  2016年   13篇
  2015年   17篇
  2014年   28篇
  2013年   61篇
  2012年   52篇
  2011年   39篇
  2010年   23篇
  2009年   14篇
  2008年   40篇
  2007年   31篇
  2006年   43篇
  2005年   28篇
  2004年   38篇
  2003年   37篇
  2002年   34篇
  2001年   18篇
  2000年   21篇
  1999年   22篇
  1998年   15篇
  1997年   7篇
  1996年   8篇
  1995年   7篇
  1994年   9篇
  1993年   7篇
  1992年   16篇
  1991年   16篇
  1990年   15篇
  1989年   13篇
  1988年   12篇
  1987年   14篇
  1986年   19篇
  1985年   18篇
  1984年   12篇
  1983年   6篇
  1982年   6篇
  1979年   7篇
  1977年   7篇
  1975年   6篇
  1974年   13篇
  1973年   8篇
  1969年   8篇
  1968年   7篇
  1967年   7篇
  1966年   12篇
排序方式: 共有988条查询结果,搜索用时 15 毫秒
31.
Early breast cancer affects one in every nine women along with their families. Advances in screening and biomedical interventions have changed the face of breast cancer from a terminal condition to a chronic disease with biopsychosocial features. The present review surveyed the nature and extent of psychological morbidity experienced by the breast cancer survivor and her spouse during the post-treatment phase, with particular focus on the impact of disease on the marital relationship. Interpersonal processes shown to unfold in couples facing breast cancer, as well as risk factors associated with greater psychological morbidity, were reviewed. Moreover, interpersonal processes central to coping with chronic illness and adjustment were reconceptualized from the point of view of attachment theory. Attachment theory was also used as the grounding framework for an empirically supported couples-based intervention, Emotionally Focused Therapy, which is advanced as a potentially useful treatment option for couples experiencing unremitting psychological and relational distress following diagnosis and treatment for breast cancer.  相似文献   
32.
Blue marlin (Makaira nigricans) stock status varies among ocean basins, and the Atlantic-wide stock is overfished. United States regulations prohibit commercial landing, importation and sale of Atlantic blue marlin, but not of Pacific or Indian Ocean conspecifics. We genotyped 344 blue marlin of known origin and 16 samples used as unknowns at 13 microsatellite loci and the mitochondrial control region. Assignment tests were conducted using GENECLASS2 to investigate the efficacy of available genotypic data to identify individual origin. We successfully discriminated Atlantic and Pacific blue marlin using genetic characters, providing more power to assign marketed blue marlin products to ocean of origin.  相似文献   
33.
Objective: The effect of nightshift on ED staff performance is of clinical and risk‐management significance. Previous studies have demonstrated deterioration in psychomotor skills but the present study specifically assessed the impact of nightshift on clinical performance. Methods: The ED registrars in a tertiary hospital were enrolled in a prospective observational study and served as their own controls. During nightshift, subjects were presented simulated scenarios and tested with eight clinical questions developed to Fellowship examination standard. Matched scenarios and questions for the same subjects during dayshift served as controls. Two investigators, blinded to subject identity and the setting in which questions were attempted, independently collated answers. Results: Of 22 eligible subjects, all were recruited; four were excluded owing to incomplete data. A correlation of 0.99 was observed between the independent scoring investigators. Of a possible score of 17, the median result for nightshift was 9.5 (interquartile range: 8–11); corresponding value for dayshift was 12 (interquartile range: 10–13); P= 0.047. Conclusion: Nightshift effect on clinical performance is anecdotally well known. The present study quantifies such effects, specifically for the ED setting, and paves the way for focused research. The implications for clinical governance strategies are significant, as the fraternity embraces the mandate to maintain quality emergency care 24 h per day.  相似文献   
34.
35.
36.
37.
Phenytoin kinetics during pregnancy and the puerperium   总被引:2,自引:0,他引:2  
During pregnancy changes in maternal physiology and plasma composition may alter drug binding and dose requirements. We have measured plasma unbound and total phenytoin, and saliva concentrations at intervals in 11 pregnant epileptics. Plasma albumin concentrations were also measured in pregnant and non-pregnant women. Saliva phenytoin correlated closely with the plasma unbound concentrations (r = 0.98). The saliva:plasma (S:P) ratio, reflecting the free fraction, was variable during pregnancy but tended to increase to maximal values at delivery and return to non-pregnant values within 2-8 weeks thereafter. Plasma albumin concentrations correlated poorly with phenytoin binding. Binding in umbilical cord plasma appeared higher than that in maternal plasma and total fetal concentrations correlated closely with maternal plasma concentrations at delivery. No ill effects of phenytoin were detected in the newborn infant. During the third trimester phenytoin dose increments were necessary to maintain therapeutic concentrations. After delivery maternal saliva phenytoin concentrations rose, and dose reductions were necessary to avoid clinical symptoms of toxicity. It is therefore appropriate to monitor saliva phenytoin concentrations regularly both during pregnancy and the puerperium.  相似文献   
38.
The auditory mismatch negativity (MMN) event-related brain potential (ERP) reflects the storage of information in acoustic sensory memory. Thirteen patients with Alzheimer's disease (AD), 6 receiving treatment with the cholinesterase inhibitor, tacrine [tetrahydroaminoacridine (THA)], and 7 receiving no treatment, were administered 2 mg of nicotine polacrilex and placebo. MMNs were recorded with 1- and 3-s interstimulus intervals (ISIs) during pre- and post-placebo/nicotine administration. Amplitudes decreased from pre- to post-placebo recordings in nontreated patients but remained stable in THA-treated patients. Comparison of pre- and post-nicotine MMNs found amplitude increases with nicotine in nontreated but not in THA-treated patients. MMN latencies were shortened by nicotine in both treatment groups. These exploratory findings suggest that nicotine-improved strength of acoustic sensory memory traces and speed of acoustic sensory discrimination in AD are differentially affected by chronic tacrine treatment.  相似文献   
39.
40.
The ascending thalamofugal visual pathway in pigeons (Columba livia) terminates in the telencephalic wulst. Characterizing the role of this pathway in visually guided behaviour has remained a challenge. To determine whether this pathway, and in particular the wulst, may participate in sun-compass-guided behaviour in homing pigeons, intact, ectostriatum-lesioned or wulst-lesioned pigeons were trained to use their sun compass to locate the direction of a food reward in an outdoor, octagonal arena. Control and ectostriatum-lesioned pigeons learned the task well, and orientated appropriately during the first trial of the last three training sessions and after a phase-shift manipulation. In contrast, the wulst-lesioned pigeons learned the task but they took more sessions to learn, and their directional choices were more scattered during the first trial of the last three training sessions and after the phase-shift manipulation. A subsequent regression analysis indicated that deeper layers of the wulst might have made more of a contribution to the observed behavioural impairments. The data indicate that the homing pigeon wulst participates in visually guided behaviour when the sun compass is used to learn the directional location of a goal.  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