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   8442篇
  免费   637篇
  国内免费   15篇
耳鼻咽喉   53篇
儿科学   285篇
妇产科学   280篇
基础医学   1027篇
口腔科学   68篇
临床医学   1412篇
内科学   1666篇
皮肤病学   93篇
神经病学   794篇
特种医学   143篇
外科学   726篇
综合类   60篇
一般理论   17篇
预防医学   1238篇
眼科学   142篇
药学   508篇
中国医学   13篇
肿瘤学   569篇
  2024年   12篇
  2023年   93篇
  2022年   110篇
  2021年   262篇
  2020年   158篇
  2019年   268篇
  2018年   263篇
  2017年   222篇
  2016年   253篇
  2015年   274篇
  2014年   326篇
  2013年   453篇
  2012年   668篇
  2011年   691篇
  2010年   367篇
  2009年   308篇
  2008年   581篇
  2007年   621篇
  2006年   634篇
  2005年   544篇
  2004年   479篇
  2003年   463篇
  2002年   407篇
  2001年   57篇
  2000年   35篇
  1999年   47篇
  1998年   52篇
  1997年   58篇
  1996年   29篇
  1995年   38篇
  1994年   33篇
  1993年   30篇
  1992年   15篇
  1991年   17篇
  1990年   20篇
  1989年   18篇
  1988年   9篇
  1987年   11篇
  1986年   8篇
  1985年   6篇
  1984年   6篇
  1983年   13篇
  1982年   16篇
  1981年   8篇
  1980年   12篇
  1979年   5篇
  1978年   9篇
  1977年   6篇
  1971年   5篇
  1965年   5篇
排序方式: 共有9094条查询结果,搜索用时 15 毫秒
11.
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   
12.
A closed femur fracture pain model was developed in the C57BL/6J mouse. One day after fracture, a monoclonal antibody raised against nerve growth factor (anti-NGF) was delivered intraperitoneally and resulted in a reduction in fracture pain-related behaviors of approximately 50%. Anti-NGF therapy did not interfere with bone healing as assessed by mechanical testing and histomorphometric analysis. INTRODUCTION: Current therapies to treat skeletal fracture pain are limited. This is because of the side effect profile of available analgesics and the scarcity of animal models that can be used to understand the mechanisms that drive this pain. Whereas previous studies have shown that mineralized bone, marrow, and periosteum are innervated by sensory and sympathetic fibers, it is not understood how skeletal pain is generated and maintained even in common conditions such as osteoarthritis, low back pain, or fracture. MATERIALS AND METHODS: In this study, we characterized the pain-related behaviors after a closed femur fracture in the C57BL/6J mouse. Additionally, we assessed the effect of a monoclonal antibody that binds to and sequesters nerve growth factor (anti-NGF) on pain-related behaviors and bone healing (mechanical properties and histomorphometric analysis) after fracture. RESULTS: Administration of anti-NGF therapy (10 mg/kg, days 1, 6, and 11 after fracture) resulted in a reduction of fracture pain-related behaviors of approximately 50%. Attenuation of fracture pain was evident as early as 24 h after the initial dosing and remained efficacious throughout the course of fracture pain. Anti-NGF therapy did not modify biomechanical properties of the femur or histomorphometric indices of bone healing. CONCLUSIONS: These findings suggest that therapies that target NGF or its cognate receptor(s) may be effective in attenuating nonmalignant fracture pain without interfering with bone healing.  相似文献   
13.
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   
14.
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   
15.
16.
17.
18.
Haemoglobin (Hgb) levels are known to be associated with numerousadverse outcomes in both chronic kidney disease (CKD) and non-CKDpatients. This analysis evaluates the association of baseline haemoglobinlevels on survival in CKD patients, who are followed by nephrologists,irrespective of glomerular filtration rate (GFR), prior to initiationof renal replacement therapy (RRT) and erythropoietin hormonereplacement therapy. Analysis of data from the provincial database (PROMIS, PatientRegistration and Outcome Management Information System) in BritishColumbia, Canada, was undertaken. Records used for the analysisincluded all CKD patients at first registration: GFR <60ml/min/1.73 m2, not yet on dialysis, starting from May 1998to October 2002, and who had complete data (defined as age andgender, diabetic status, eGFR and Hgb levels). The primary objective of this study was to determine the associationof Hgb and survival controlling for eGFR at first registrationvalue, age, gender and diabetic status. Multivariate Cox proportionalhazards analysis with time to death as outcome variable wasperformed. The cohort included 3028 patients: the mean age was 65 years,28% were diabetic, and the mean eGFR in the cohort was 21 ml/min/1.73m2. The cohort is representative of the BC CKD and dialysispopulation regarding ethnicity: 64% Caucasian, 32% Asian. Medianfollow-up was 27 months, 1 year survival was 0.92, 2 year survivalwas 0.85. Hgb at initial registration is a statistically independentpredictor of survival (RR = 0.875 for every 10 g/l, 95% CI:0.835–0.917, P = 0.0001), after adjusting for age, gender,diabetic status and baseline eGFR. Further analysis, controllingfor RRT, demonstrated a similar association between Hgb andsurvival (RR = 0.853 for every 10 g/l, 95% CI: 0.799–0.910,P = 0.0001), after adjusting for above variables. Substantialvariation in Hgb values exists at all GFR levels. These findings underscore the importance of evaluating Hgb atall GFR levels, and the need to study the impact of modificationof Hgb at different GFR levels on survival.  相似文献   
19.
Sadly, intrauterine fetal death is a common occurrence and one that all labour ward personnel should be trained to manage. Recent advances have improved the likelihood of identifying a cause. The key to this is a logical and methodical approach to investigation. Postmortem examination remains a critical aspect of investigation and labour ward teams require a clear understanding of the legal aspects of this. Sympathetic and supportive care of parents should respect parental wishes and allow choice wherever possible. However, maternal safety should also be a central aspect of this care.  相似文献   
20.
Homicide inflicts massive injury upon the intrapsychic and interpersonal realities of the surviving kin of murder victims. A New York City pilot program of outreach and counselling to 1182 families of Brooklyn homicide victims suggests that surviving kin undergo the symptoms of traumatic stress disorder. Recovery is prolonged by knowledge that the perpetrator is usually alive and in some cases unpunished, by repetitive confrontations with the criminal justice system and by the multiple losses endured: loss of a family member, loss of illusions of safety and invulnerability, loss of a sense of trust in the surrounding community, and loss of a belief system. Effective help to survivors requires interventions that respond to all aspects of the survivors' losses.  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