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   23458篇
  免费   2120篇
  国内免费   1062篇
耳鼻咽喉   573篇
儿科学   274篇
妇产科学   176篇
基础医学   637篇
口腔科学   482篇
临床医学   7255篇
内科学   1994篇
皮肤病学   58篇
神经病学   1477篇
特种医学   486篇
外国民族医学   2篇
外科学   4999篇
综合类   2982篇
预防医学   1805篇
眼科学   293篇
药学   1323篇
  71篇
中国医学   965篇
肿瘤学   788篇
  2024年   135篇
  2023年   579篇
  2022年   1187篇
  2021年   1471篇
  2020年   1456篇
  2019年   1161篇
  2018年   1067篇
  2017年   1033篇
  2016年   1029篇
  2015年   940篇
  2014年   1985篇
  2013年   2422篇
  2012年   1424篇
  2011年   1435篇
  2010年   1160篇
  2009年   981篇
  2008年   1046篇
  2007年   1060篇
  2006年   859篇
  2005年   682篇
  2004年   530篇
  2003年   538篇
  2002年   483篇
  2001年   377篇
  2000年   279篇
  1999年   234篇
  1998年   159篇
  1997年   134篇
  1996年   96篇
  1995年   109篇
  1994年   77篇
  1993年   51篇
  1992年   70篇
  1991年   49篇
  1990年   33篇
  1989年   30篇
  1988年   37篇
  1987年   29篇
  1986年   32篇
  1985年   37篇
  1984年   16篇
  1983年   12篇
  1982年   28篇
  1981年   18篇
  1980年   24篇
  1979年   12篇
  1978年   8篇
  1977年   6篇
  1976年   12篇
  1974年   3篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Although methadone is effective in the management of acute pain, the complexity of its absorption-distribution-metabolism-excretion profile limits its use as an opioid of choice for perioperative analgesia. Because deuteration is known to improve the pharmacokinetic, pharmacodynamic and toxicological properties of some drugs, here we characterized the single dose pharmacokinetic properties and post-operative analgesic efficacy of d9-methadone.The pharmacokinetic profiles of d9-methadone and methadone administered intravenously to CD-1 male mice revealed that deuteration leads to a 5.7- and 4.4-fold increase in the area under the time-concentration curve and maximum concentration in plasma, respectively, as well as reduction in clearance (0.9 ± 0.3 L/h/kg vs 4.7 ± 0.8 L/h/kg). The lower brain-to-plasma ratio of d9-methadone compared to that of methadone (0.35 ± 0.12 vs 2.05 ± 0.62) suggested that deuteration decreases the transfer of the drug across the blood-brain barrier. The estimated LD50 value for a single intravenous dose of d9-methadone was 2.1-fold higher than that for methadone. Moreover, d9-methadone outperformed methadone in the efficacy against postoperative pain by primarily activating peripheral opioid receptors. Collectively, these data suggest that the replacement of three hydrogen atoms in three methyl groups of methadone altered its pharmacokinetic properties, improved safety, and enhanced its analgesic efficacy.  相似文献   
2.
3.
While previous randomised controlled trials and meta-analyses offer only limited evidence for the effectiveness of cognitive rehabilitation, qualitative studies examining patient perspectives report more positive outcomes. This meta-synthesis of qualitative studies examined patient perspectives of cognitive rehabilitation for memory, attention, and executive function problems in people with multiple sclerosis. Using set eligibility criteria, we screened electronic databases, reference lists, and academic networks for relevant papers. Seven papers (195 participants) were selected. Two independent researchers conducted quality appraisals of papers. Data analysis, guided by the thematic synthesis approach, yielded six main themes. These suggested that patients benefitted from the group environment in rehabilitation. Cognitive rehabilitation facilitated the participants’ reflection and awareness of their cognitive deficits, and was associated with increased knowledge and understanding of their illness. Increased strategy use was reported and associated with improvements in cognitive functioning and greater confidence and perseverance. Participants reported emotional and social improvements, and felt more optimistic. Overall, these changes had a positive impact on participants’ quality of life. This synthesis of qualitative studies indicates that people with multiple sclerosis who experience cognitive deficits benefit from cognitive rehabilitation programmes. This finding must, however, be viewed in light of the limitations of this meta-synthesis. The meta-synthesis was registered in the PROSPERO database under CRD42017040148.  相似文献   
4.
5.
目的观察妇科腹腔镜手术围术期碳水化合物口服疗法和传统禁饮食方案两种不同的临床处理措施对于术后胰岛素抵抗(IR)的影响。 方法选取2018年2月至8月入住徐州医科大学附属医院妇科,行腹腔镜下全子宫切除手术的非糖尿病患者共98例,将采用围术期碳水化合物口服疗法者作为观察组(50例),采用传统禁饮食方案者作为对照组(48例)。检测所有病例的术前、术后第1天及第3天的空腹血糖(FPG)及空腹胰岛素(FINS),并利用稳态模式评估法计算稳态模型胰岛素抵抗指数(HOME-IR)。对于观察组与对照组患者术前、术后第1天和术后第3天的FPG、FINS和HOME-IR等指标,组间比较采用独立样本t检验。两组患者术后腹胀、术后24 h通气、术后发热的发生情况的比较采用确切概率法检验。 结果观察组与对照组比较,术前和术后第1天FPG差异无统计学意义(P均>0.05),术后第3天FPG明显降低[(4.34±0.59)mmol/L vs (4.96±0.64)mmol/L],差异有统计学意义(t=-4.96,P=0.002)。观察组与对照组比较,术前和术后第1天FINS差异无统计学意义(P均>0.05),术后第3天FINS明显降低[(45.39±13.55)mIU/L vs (51.18±9.34) mIU/L],差异有统计学意义(t=-2.46,P=0.033)。观察组与对照组比较,术前HOME-IR差异无统计学意义(P>0.05),术后第1天和术后第3天HOME-IR明显降低[(13.08±4.80)vs (15.03±4.11);(9.37±3.65)vs (11.30±2.55)],差异有统计学意义(t=-0.69,P=0.042;t=-3.99,P=0.033)。两组患者术后其他观察指标比较,观察组术后24 h通气率与对照组比较明显增高(76.0% vs 64.6%),差异有统计学意义(P=0.045)。两组患者在术后腹胀、术后发热的发生率方面差异无统计学意义(P均>0.05)。两组患者均未发生术中误吸。 结论妇科腹腔镜手术围术期应用碳水化合物口服疗法较传统禁饮食方案,能有效减轻术后IR程度,促进术后康复进程,且不增加围术期并发症的发生率。  相似文献   
6.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
7.
舌癌患者手术及放化疗后会出现构音障碍、吞咽困难、口腔黏膜炎、口干、营养不良等并发症,使患者生存质量下降,甚至导致肿瘤的复发转移,影响生存期,单一方法往往顾此失彼。依托于中国中医科学院西苑医院肿瘤康复基地,杨宇飞教授在国内外调研考察基础上,结合中国国情,构建了一种“门诊多学科肿瘤康复模式”,在舌癌康复方面,以患者为中心,以中医肿瘤内科为主导,多学科共同参与,结合康复科、口腔科、营养科、药剂科等各科优势,形成全程个体化规范序贯康复方案,对患者及早进行康复,在放疗前进行预防性干预尤其重要,使患者能够快速缓解手术和放疗的不良反应,患者获益明显。现取两个典型案例总结其舌癌多学科康复的经验,以期为舌癌的康复提供借鉴。  相似文献   
8.
Conducting high-quality clinical research is dependent on merging scientific rigor with the clinical environment. This is often a complex endeavor that may include numerous barriers and competing interests. Overcoming these challenges and successfully integrating clinical research programs into clinical practice settings serving rehabilitation outpatients is beneficial from both a logistical perspective (eg, supports efficient and successful research procedures) and the establishment of a truly patient-centered research approach. Leveraging our experience with navigating this research-clinical care relationship, this article (1) proposes the Patient-Centered Framework for Rehabilitation Research, a model for integrating patient-centered research in an outpatient clinical setting that incorporates a collaborative, team-based model encompassing patient-centered values, as well as strategies for recruitment and retention, with a focus on populations living with disabilities or chronic diseases; (2) describes application of this framework in a comprehensive specialty multiple sclerosis center with both general strategies and specific examples to guide adaptation and implementation in other settings; and (3) discusses the effect of the framework as a model in 1 center, as well as the need for additional investigation and adaptation for other populations. The 5 interconnected principles incorporated in the Framework and which prioritize patient-centeredness include identifying shared values, partnering with the clinical setting, engaging with the population, building relationships with individuals, and designing accessible procedures. The Patient-Centered Framework for Rehabilitation Research is a model presented as an adaptable roadmap to guide researchers in hopes of not only improving individual patients’ experiences but also the quality and relevance of rehabilitation research as a whole. Future investigation is needed to test the Framework in other settings.  相似文献   
9.
IntroductionTranssphenoidal surgical removal is the preferred treatment of most pituitary adenomas. Postoperative cerebrospinal fluid (CSF) leakage is the leading cause of morbidity after this procedure, with an incidence rate that varies from 0,5-15% in the main published series.ObjectivesThe primary objective of this study was to establish the incidence of postoperative CSF leakage in a sample of surgeries performed at the University Hospital of La Ribera by the same surgical team. The secondary objectives were to: ascertain the distinctive features between patients with and without postoperative CSF leakage, identify risk factors for their development, evaluate the relationship between the surgical technique for closing the sella turcica and the onset of postoperative CSF leakage and evaluate different treatment regimens for this complication.MethodsThe data of 302 consecutive transsphenoidal surgical procedures for pituitary adenoma removal which were performed between 1999 and 2017 were retrospectively reviewed.Results and conclusionsThe incidence of postoperative CSF leakage in our series was 2,3% (in accordance with similar published studies). It was possible to correlate intraoperative CSF leakage with two variables: pituitary macroadenoma and tumors with suprasellar extension (P < .005). This correlation did not exist for postoperative CSF leakage. We found a statistically significant correlation between intraoperative and postoperative CSF leakage (P < .005). Due to the low incidence of postoperative CSF leakage in our series, it was not possible to identify risk factors for its development.  相似文献   
10.
目的 通过比较全身运动(GMs)评估正常的高危儿单纯家庭康复训练与家庭康复训练联合药物干预的预后,分析GMs对高危儿早期干预的指导意义。方法 选取2016年2月-2017年2月于潍坊市妇幼保健院康复科就诊并接受GMs评估正常的183例高危儿,随机分组为观察组和对照组,观察组为单纯家庭康复训练组89例,对照组为家庭康复训练联合药物干预组94例。采用Peabody运动发育量表对两组患儿分别于纠正月龄6、9、12个月龄进行评估,对Peabody运动发育量表中各指标应用SPSS 21.0进行统计分析。结果 干预后,纠正月龄6、9、12个月龄时,观察组和对照组Peabody运动发育量表中粗大运动商(GMQ)、精细运动商(FMQ)、总运动商(TMQ)比较,差异无统计学意义(P>0.05),重复测量方差分析发现观察组和对照组的GMQ、FMQ、TMQ评分的组间效应差异无统计学意义(P>0.05),时间效应差异有统计学意义(P<0.05),干预因素与时间因素不存在交互作用(P>0.05)。结论 GMs评估对高危儿早期干预具有指导意义。GMs评估正常者,家庭康复训练可达到促进高危儿运动功能发育的目的 ,避免仅因系高危儿而采取“过度干预”。  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