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   1213472篇
  免费   77107篇
  国内免费   1526篇
耳鼻咽喉   15408篇
儿科学   34317篇
妇产科学   28844篇
基础医学   166282篇
口腔科学   31936篇
临床医学   105192篇
内科学   232984篇
皮肤病学   21420篇
神经病学   97829篇
特种医学   48813篇
外国民族医学   87篇
外科学   196108篇
综合类   22431篇
现状与发展   1篇
一般理论   342篇
预防医学   91524篇
眼科学   26057篇
药学   89849篇
  4篇
中国医学   2879篇
肿瘤学   79798篇
  2018年   33491篇
  2017年   26588篇
  2016年   30534篇
  2015年   11393篇
  2014年   14958篇
  2013年   21550篇
  2012年   35529篇
  2011年   51517篇
  2010年   36517篇
  2009年   28974篇
  2008年   49931篇
  2007年   54829篇
  2006年   31411篇
  2005年   32552篇
  2004年   32988篇
  2003年   33404篇
  2002年   30579篇
  2001年   57423篇
  2000年   59582篇
  1999年   49335篇
  1998年   12149篇
  1997年   10748篇
  1996年   10629篇
  1995年   9914篇
  1994年   9257篇
  1993年   8479篇
  1992年   37387篇
  1991年   35775篇
  1990年   34532篇
  1989年   33598篇
  1988年   30624篇
  1987年   29850篇
  1986年   27845篇
  1985年   26682篇
  1984年   19121篇
  1983年   16367篇
  1982年   8695篇
  1981年   7467篇
  1979年   16935篇
  1978年   11451篇
  1977年   9765篇
  1976年   8620篇
  1975年   9297篇
  1974年   11292篇
  1973年   10543篇
  1972年   10023篇
  1971年   9412篇
  1970年   8996篇
  1969年   8480篇
  1968年   7720篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Blecha  S.  Weber-Carstens  S.  Bein  T. 《Der Anaesthesist》2019,68(6):343-352
Die Anaesthesiologie - Die Versorgungsforschung (VF) ist ein fachübergreifendes multidisziplinäres Forschungsgebiet, das die Kranken- und Gesundheitsversorgung sowie ihre...  相似文献   
92.
93.
Ovarian carcinoma is one of the most lethal malignancies, but only very few prognostic biomarkers are known. The degradome, comprising proteases, protease non-proteolytic homologues and inhibitors, have been involved in the prognosis of many cancer types, including ovarian carcinoma. The prognostic significance of the whole degradome family has not been specifically studied in high-grade serous ovarian cancer. A targeted DNA microarray known as the CLIP-CHIP microarray was used to identify potential prognostic factors in ten high-grade serous ovarian cancer women who had early recurrence (<1.6 years) or late/no recurrence after first line surgery and chemotherapy. In women with early recurrence, we identified seven upregulated genes (TMPRSS4, MASP1/3, SPC18, PSMB1, IGFBP2, CFI – encoding Complement Factor I – and MMP9) and one down-regulated gene (ADAM-10). Using immunohistochemistry, we evaluated the prognostic effect of these 8 candidate genes in an independent cohort of 112 high-grade serous ovarian cancer women. Outcomes were progression, defined according to CA-125 criteria, and death. Multivariate Cox proportional hazard regression models were done to estimate the associations between each protein and each outcome. High ADAM-10 expression (intensity of 2–3) was associated with a lower risk of progression (adjusted hazard ratio (HR): 0.51; 95% confidence interval (CI): 0.29-0.87). High complement factor I expression (intensity 2–3) was associated with a higher risk of progression (adjusted HR: 2.30, 95% CI: 1.17–4.53) and death (adjusted HR: 3.42; 95% CI: 1.72–6.79). Overall, we identified the prognostic value of two proteases, ADAM-10 and complement factor I, for high-grade serous ovarian cancer which could have clinical significance.  相似文献   
94.
95.

Background

Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.

Methods

A total of 459 total hip arthroplasties performed for osteoarthritis using imageless navigation were reviewed from a single surgeon’s institutional review board–approved database. Einzel-Bild-Roentgen Analyse determined component orientation on 6-week postoperative anteroposterior radiographs. Mean orientation error (accuracy) and precision were compared between obese (body mass index ≥ 30 kg/m2) and nonobese patients. Regression analysis evaluated the influence of obesity on component position.

Results

The difference in mean inclination and anteversion between obese and nonobese groups was 1.1° (43.0° ± 3.5°; range, 35.8°-57.8° vs 41.9° ± 4.4°; range, 33.0°-57.1° and 24.9° ± 6.3°; range, 14.2°-44.3° vs 23.8° ± 6.6°; range, 7.0°-38.6°, respectively). Inclination precision was better for nonobese patients. No difference in inclination accuracy or anteversion accuracy or precision was detected between groups. And 83% of components were placed within the target range. There was no relationship between obesity (dichotomized) and component placement outside the target ranges for inclination, anteversion, or both. As a continuous variable, increased body mass index correlated with higher odds of inclination outside the target zone (odds ratio, 1.06; P = .001).

Conclusion

Using imageless navigation, inclination orientation was less precise for obese patients, but the observed difference is likely not clinically relevant. Accurate superficial registration of landmarks in obese patients is achievable, and the use of imageless navigation similarly improves acetabular component positioning in obese and nonobese patients.

Level of Evidence

Therapeutic Level IV.  相似文献   
96.

Background

The Lancet Commission on Global Surgery highlighted global surgical need but offered little insight into the specific surgical challenges of children in low-resource settings. Efforts to strengthen the quality of global pediatric surgical care have resulted in a proliferation of partnerships between low-and middle-income countries (LMICs) and high-income countries (HICs). Standardized tools able to reliably measure gaps in delivery and quality of care are important aids for these partnerships. We undertook a systematic review (SR) of capacity assessment tools (CATs) focused on needs assessment in pediatric surgery.

Methods

A comprehensive search strategy of multiple electronic databases was conducted per PRISMA guidelines without linguistic or temporal restrictions. CATs were selected according to pre-defined inclusion criteria. Articles were assessed by two independent reviewers. Methodological quality of studies was appraised using the COSMIN checklist with 4-point scale.

Results

The search strategy generated 16,641 original publications, of which three CATs were deemed eligible. Eligible tools were either excessively detailed or oversimplified. None used weighted scores to identify finer granularity between institutions. No CATs comprehensively included measures of resources, outcomes, accessibility/impact and training.

Discussion

The results of this study identify the need for a CAT capable of objectively measuring key aspects of surgical capacity and performance in a weighted tool designed for pediatric surgical centers in LMICs.

Type of Study

Systematic Review.

Level of Evidence

II.  相似文献   
97.
Hillermann  T.  Homburg  K.  Rainer  M.  Budde  U. 《Der Anaesthesist》2022,71(4):299-302
Die Anaesthesiologie - Eine junge Patientin erleidet während der Anlage einer axillären Plexusblockade einen generalisierten Krampfanfall. Die Mechanismen, im Wesentlichen die vermutlich...  相似文献   
98.
99.
100.
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