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   953609篇
  免费   69728篇
  国内免费   1374篇
耳鼻咽喉   13231篇
儿科学   25342篇
妇产科学   23757篇
基础医学   135757篇
口腔科学   28611篇
临床医学   83478篇
内科学   186656篇
皮肤病学   19664篇
神经病学   74589篇
特种医学   37430篇
外国民族医学   80篇
外科学   155363篇
综合类   18557篇
现状与发展   1篇
一般理论   254篇
预防医学   64645篇
眼科学   21663篇
药学   74343篇
  3篇
中国医学   2191篇
肿瘤学   59096篇
  2018年   9758篇
  2017年   7582篇
  2016年   8297篇
  2015年   9458篇
  2014年   12824篇
  2013年   18705篇
  2012年   25775篇
  2011年   26809篇
  2010年   15763篇
  2009年   15120篇
  2008年   25976篇
  2007年   27071篇
  2006年   27802篇
  2005年   26718篇
  2004年   25743篇
  2003年   24749篇
  2002年   24216篇
  2001年   55262篇
  2000年   57011篇
  1999年   47330篇
  1998年   10941篇
  1997年   9639篇
  1996年   9787篇
  1995年   9066篇
  1994年   8424篇
  1993年   7717篇
  1992年   35768篇
  1991年   34182篇
  1990年   33024篇
  1989年   32113篇
  1988年   29182篇
  1987年   28476篇
  1986年   26451篇
  1985年   25324篇
  1984年   17968篇
  1983年   15232篇
  1982年   7865篇
  1981年   6819篇
  1979年   15893篇
  1978年   10707篇
  1977年   9117篇
  1976年   7943篇
  1975年   8695篇
  1974年   10560篇
  1973年   9944篇
  1972年   9421篇
  1971年   8921篇
  1970年   8470篇
  1969年   8004篇
  1968年   7257篇
排序方式: 共有10000条查询结果,搜索用时 484 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
2.
3.
4.
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.

Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.

Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings.  相似文献   

5.
6.
7.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
8.
Aims: In neuropsychological evaluations, it is often difficult to ascertain whether poor performance on measures of validity is due to poor effort or malingering, or whether there is genuine cognitive impairment. Dunham and Denney created an algorithm to assess this question using the Medical Symptom Validity Test (MSVT). We assessed the ability of their algorithm to detect poor validity versus probable impairment, and concordance of failure on the MSVT with other freestanding tests of performance validity.

Methods: Two previously published datasets (n?=?153 and n?=?641, respectively) from outpatient neuropsychological evaluations were used to test Dunham and Denney’s algorithm, and to assess concordance of failure rates with the Test of Memory Malingering and the forced choice measure of the California Verbal Learning Test, two commonly used performance validity tests.

Results: In both datasets, none of the four cutoff scores for failure on the MSVT (70%, 75%, 80%, or 85%) identified a poor validity group with proportionally aligned failure rates on other freestanding measures of performance validity. Additionally, the protocols with probable impairment did not differ from those with poor validity on cognitive measures.

Conclusions: Despite what appeared to be a promising approach to evaluating failure on the easy MSVT subtests when clinical data are unavailable (as recommended in the advanced interpretation program, or advanced interpretation [AI], of the MSVT), the current findings indicate the AI remains the gold standard for doing so. Future research should build on this effort to address shortcomings in measures of effort in neuropsychological evaluations.  相似文献   

9.
10.
There is evidence that caesarean section delivery can impact on neonatal weight loss and weight gain patterns in the first 5 days of life. We conducted an integrative systematic review to examine the association of mode of delivery on early neonatal weight loss. Pubmed, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Excerpta Medica dataBASE, and Medical Literature Analysis and Retrieval System Online were searched for relevant papers published before June 2019. Reference lists from the relevant papers were then backwards and forwards searched. As neonatal weight loss was reported in different formats, a meta‐analysis could not be carried out. Most studies did not distinguish between elective and emergency caesarean sections or instrumental and nonassisted vaginal deliveries. Seven papers were included. All papers except one found that caesarean section was associated with higher weight loss in the early days of life. Two papers presented data from studies on babies followed up to 1 month. One study found that on day 25, babies born by caesarean section had significantly higher weight gain than those born vaginally, while another found that by day 28, babies born vaginally gained more weight per day (11.9 g/kg/day) than those born by caesarean section (10.9 g/kg/day; p = .02). Overall, infants born by caesarean section lost more weight than those born vaginally, but due to the small number of studies included, more are needed to look at this difference and why it may occur. This discrepancy in weight between the two groups may be corrected over time, but future studies will need larger sample sizes and longer follow‐up periods to examine this.  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