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   3577篇
  免费   249篇
  国内免费   6篇
耳鼻咽喉   15篇
儿科学   148篇
妇产科学   154篇
基础医学   336篇
口腔科学   59篇
临床医学   762篇
内科学   722篇
皮肤病学   27篇
神经病学   222篇
特种医学   39篇
外科学   319篇
综合类   26篇
一般理论   6篇
预防医学   573篇
眼科学   18篇
药学   206篇
中国医学   5篇
肿瘤学   195篇
  2023年   21篇
  2022年   23篇
  2021年   79篇
  2020年   46篇
  2019年   63篇
  2018年   85篇
  2017年   76篇
  2016年   87篇
  2015年   92篇
  2014年   107篇
  2013年   185篇
  2012年   252篇
  2011年   285篇
  2010年   158篇
  2009年   140篇
  2008年   255篇
  2007年   315篇
  2006年   330篇
  2005年   262篇
  2004年   228篇
  2003年   206篇
  2002年   197篇
  2001年   33篇
  2000年   22篇
  1999年   22篇
  1998年   25篇
  1997年   20篇
  1996年   14篇
  1995年   17篇
  1994年   9篇
  1993年   14篇
  1992年   11篇
  1991年   18篇
  1990年   16篇
  1989年   18篇
  1988年   15篇
  1987年   8篇
  1986年   11篇
  1985年   6篇
  1984年   8篇
  1983年   5篇
  1981年   3篇
  1980年   3篇
  1978年   3篇
  1976年   6篇
  1974年   6篇
  1973年   3篇
  1972年   3篇
  1971年   3篇
  1967年   4篇
排序方式: 共有3832条查询结果,搜索用时 15 毫秒
1.
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year.  相似文献   
2.
3.
4.
OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported.  相似文献   
5.
6.
7.
8.
OBJECTIVE: To identify the etiology and impact of preterm delivery in twin gestations. STUDY DESIGN: Twin gestations delivered at 33.0 to 36.9 weeks were identified in a perinatal database, and categorized by indication for delivery. Deliveries were identified as indicated, or non-indicated (discretionary). Neonatal outcomes were measured by birth weight, length of stay, NICU admission, and ventilator utilization. Data were divided and analyzed by indicated or discretionary delivery, and gestational age at delivery. RESULTS: Analyzed were 3252 twin gestations (6504 infants), with 78% having indicated delivery. Of the 22% with discretionary delivery, nearly 40% required NICU admission. With each advancing week of gestation, there was a significant decrease in incidence of NICU admission and nursery days. CONCLUSION: The majority of preterm deliveries were indicated, though 22% were discretionary. It is vital to consider neonatal morbidity and costs related to gestational age when choosing discretionary delivery.  相似文献   
9.
Chlamydia trachomatis is the most prevalent sexually transmitted microbial infection in the United States. The CDC estimates that 3 million people are infected annually, with approximately 50% of infected men and 75% of infected women having few or no recognized symptoms. C. trachomatis is frequently transferred from mother to infant, and the maternal-infant transfer of this disease may have negative consequences for the newborn, such as prematurity, pneumonia, and conjunctivitis. Ocular prophylaxis with silver nitrate and or antibiotics is ineffective in preventing neonatal chlamydial conjunctivitis. By increasing awareness of the potential adverse consequences, initiating screening and treatment of pregnant women, and advocating for newborn assessment and treatment, nurses can enhance the quality of care for mothers and their infants.  相似文献   
10.
OBJECTIVES: The 585nm pulsed dye laser (PDL) is a promising tool for in-office laryngeal surgery. Data with respect to the safety and efficacy of the PDL for office laryngeal use is sparse. The purpose of this study is to review our experience with unsedated office PDL surgery. METHODS: Records of individuals undergoing in-office PDL between September 1, 2004, and September 1, 2006 were abstracted from a clinical database. RESULTS: Forty-seven patients underwent 117 treatments. The most common indications were recurrent respiratory papillomatosis (RRP), Reinke's edema, and vocal fold polyps. One hundred and four of 117 procedures were felt to be a success ablating all disease. Thirteen treatments required early termination. The most common factor responsible for termination was an inability to achieve a comfortable level of anesthesia. One patient with Reinke's edema developed postprocedure stridor that required a 3-day hospital admission for observation and corticosteroids. There was no incidence of any vocal fold scarring, web formation, or other complications. CONCLUSIONS: The 585nm PDL is a promising tool for in-office treatment of various laryngeal disorders. Complications are rare.  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