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   1297篇
  免费   37篇
  国内免费   12篇
耳鼻咽喉   8篇
儿科学   52篇
妇产科学   12篇
基础医学   100篇
口腔科学   13篇
临床医学   97篇
内科学   131篇
皮肤病学   34篇
神经病学   34篇
特种医学   236篇
外科学   150篇
综合类   284篇
预防医学   35篇
眼科学   21篇
药学   49篇
肿瘤学   90篇
  2023年   5篇
  2022年   8篇
  2021年   11篇
  2020年   5篇
  2019年   8篇
  2018年   11篇
  2017年   9篇
  2016年   8篇
  2015年   37篇
  2014年   22篇
  2013年   32篇
  2012年   37篇
  2011年   31篇
  2010年   58篇
  2009年   56篇
  2008年   49篇
  2007年   53篇
  2006年   72篇
  2005年   54篇
  2004年   76篇
  2003年   37篇
  2002年   33篇
  2001年   31篇
  2000年   55篇
  1999年   49篇
  1998年   52篇
  1997年   58篇
  1996年   65篇
  1995年   39篇
  1994年   38篇
  1993年   10篇
  1992年   17篇
  1991年   12篇
  1990年   8篇
  1989年   16篇
  1988年   18篇
  1987年   15篇
  1986年   13篇
  1985年   14篇
  1984年   14篇
  1983年   10篇
  1982年   11篇
  1981年   7篇
  1980年   7篇
  1979年   6篇
  1977年   5篇
  1975年   7篇
  1974年   6篇
  1972年   5篇
  1968年   4篇
排序方式: 共有1346条查询结果,搜索用时 31 毫秒
71.
Objective: We aimed to evaluate a multifaceted education initiative designed to reduce the prophylactic use of metoclopramide. Methods: This was a pre‐ and post‐intervention trial undertaken in a single ED. All ED doctors and nurses were targeted. The intervention comprised a specifically designed, 19‐slide ‘e‐learning module’, accessible via the ED intranet, supplemented by in‐service training and a range of reminder techniques (posters, emails and drug room flyers). The primary end‐point was the proportion of patients administered metoclopramide prophylactically with their initial morphine dose. Data were collected on random samples of patients who received morphine, using explicit medical chart review. Results: Both pre‐ and post‐intervention periods were of 3 month duration. The charts of 146 cases were reviewed in each period. In the post‐intervention period: ? The proportion of patients administered metoclopramide prophylactically decreased from 22.6% to 4.1% (difference 18.5% [95% CI 10.3–26.7], P < 0.001) ? The proportion of patients administered metoclopramide appropriately (for known morphine sensitivity, established nausea and rescue anti‐emesis) rose marginally from 28.8% to 32.9% (difference 4.1% [95% CI ?7.2–15.4], P = 0.53) ? There was a 12.7% decrease in the number of ampoules of metoclopramide issued to the ED without a concurrent rise in the issue of other anti‐emetic drugs Conclusion: The education initiative resulted in a significant improvement in the evidence‐based use of metoclopramide.  相似文献   
72.
73.
Background  Quadrivalent human papillomavirus (HPV types 6/11/16/18) L1 VLP vaccine is highly effective in preventing HPV 6/11/16/18-related cervical and external genital disease. Herein, we evaluated the impact of the quadrivalent HPV 6/11/16/18 L1 VLP vaccine on prevention of HPV-associated cervico-genital lesions in a broad population of sexually active European women.
Methods  Female subjects ( N = 9265) aged 16–24 with four or fewer lifetime sexual partners were enrolled and randomized to quadrivalent HPV vaccine or placebo. Subjects underwent cervicovaginal sampling for HPV DNA detection. Papanicolaou testing and anti-HPV 6/11/16/18 serology testing was also performed.
Results  Vaccine efficacy against lesions representing immediate cervical cancer precursors (cervical intraepithelial neoplasia grade 2/3 or adenocarcinoma in situ ) related to HPV 6/11/16/18 in the per-protocol population was 100.0%[95% confidence interval (95% CI), 89.8–100.0]. Efficacy against external genital lesions (vulvar or vaginal intraepithelial neoplasia, condyloma, vulvar or vaginal cancer) related to vaccine HPV types in the per-protocol European population was 99.0% (95% CI, 94.4–100.0).
Conclusion  These data demonstrate that quadrivalent HPV 6/11/16/18 vaccination programs in 16- to 24-year-old European women can be beneficial.
NCT0009252, NCT00092534, NCT00092495  相似文献   
74.
Chui  DH; Liao  SK; Walker  K 《Blood》1978,51(3):539-547
Erythroid progenitor cells in +/+ and Sl/Sld fetal livers manifested as burst-forming units-erythroid (BFU-E) and colony-forming units- erythroid (CFU-E) were assayed in vitro during early development. The proportion of BFU-E was higher as mutant than in normal fetal livers. On the other hand, the proportion of CFU-E was less in the mutant than in the normal. These results suggest that the defect in Sl/Sld fetal hepatic erythropoiesis is expressed at the steps of differentiation that effect the transition from BFU-E to CFU-E.  相似文献   
75.
BackgroundObstructive sleep apnea (OSA) is common after stroke and associated with poor stroke outcomes. Whether OSA after acute stroke is caused by anatomic, physiologic, or both etiologies has not been studied. We therefore used brain magnetic resonance imaging (MRI) scans to assess oropharyngeal anatomy in stroke patients with and without OSA.MethodsPatients within 7 days of ischemic stroke underwent nocturnal polysomnography. Sagittal T1-weighted MRI performed for clinical purposes was used to measure retropalatal distance, soft palatal length, soft palatal thickness, retroglossal space, and tongue length. Nasopharyngeal area and high retropharyngeal area were measured from axial T2-weighted images, and lateral pharyngeal wall thickness from coronal T1-weighted images.ResultsAmong 27 subjects, 18 (67%) had OSA (apnea/hypopnea index (AHI) ? 5). Demographics, vascular risk factors, and stroke severity were similar in the two groups. Median retropalatal distance was shorter in subjects with OSA (Wilcoxon rank-sum test, p = 0.03). Shorter retropalatal distance was associated with higher AHI (linear regression, p = 0.04). None of the other morphological characteristics differed.ConclusionsAnatomic difference between awake acute stroke patients with and without OSA shows that the sleep disorder cannot be attributed solely to sleep, sleeping position, or changes in neuromuscular control that are specific to the sleep state.  相似文献   
76.
Neurohydatidosis     
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature.  相似文献   
77.
78.
A study was undertaken to determine the usefulness of ultrasonography as an investigative tool, and its role in deciding the management of Peyronie's disease. Fifteen patients with Peyronie's disease were studied by ultrasonography. The plaque could be demonstrated in all patients. The dimensions of the plaque varied from less than 1 cm to more than 7cm in length and 2-4mm in thickness. The disease was active in 26% of the patients, as indicated by the presence of hypoechoic areas around a central region of hyperechoism. Ultrasonogram was more accurate than clinical assessment in delineating the extent of lesions. In one-third of the patients, sonography demonstrated the plaques to be more extensive than had been detected by clinical examination. Calcification and activity of disease (which are clearly defined by ultrasonogram) are determining factors in the management of Peyronie's disease. This information allows the surgeon to select the modality of treatment, the timing of surgery and extent of excision. Thus, ultrasonography plays a vital role in the preliminary investigation and management of Peyronie's disease.  相似文献   
79.
80.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  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