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   8477篇
  免费   493篇
  国内免费   105篇
耳鼻咽喉   92篇
儿科学   135篇
妇产科学   164篇
基础医学   904篇
口腔科学   314篇
临床医学   683篇
内科学   2535篇
皮肤病学   90篇
神经病学   887篇
特种医学   300篇
外科学   1326篇
综合类   19篇
一般理论   1篇
预防医学   399篇
眼科学   73篇
药学   467篇
中国医学   20篇
肿瘤学   666篇
  2024年   16篇
  2023年   141篇
  2022年   279篇
  2021年   521篇
  2020年   297篇
  2019年   341篇
  2018年   384篇
  2017年   265篇
  2016年   315篇
  2015年   346篇
  2014年   442篇
  2013年   500篇
  2012年   687篇
  2011年   607篇
  2010年   352篇
  2009年   333篇
  2008年   469篇
  2007年   442篇
  2006年   394篇
  2005年   323篇
  2004年   272篇
  2003年   251篇
  2002年   182篇
  2001年   90篇
  2000年   84篇
  1999年   64篇
  1998年   42篇
  1997年   23篇
  1996年   33篇
  1995年   29篇
  1994年   23篇
  1993年   13篇
  1992年   41篇
  1991年   41篇
  1990年   37篇
  1989年   46篇
  1988年   41篇
  1987年   34篇
  1986年   31篇
  1985年   28篇
  1984年   24篇
  1979年   20篇
  1978年   18篇
  1977年   14篇
  1976年   17篇
  1974年   16篇
  1973年   10篇
  1971年   11篇
  1970年   10篇
  1969年   13篇
排序方式: 共有9075条查询结果,搜索用时 15 毫秒
31.
A new testicular prosthesis for pediatric use is presented. This differs from the model usually available in that it is pink-pigmented and opaque. Over a period of 2 years and 6 months, 57 testicular prostheses were implanted in 53 boys. Seventeen of these were opaque, pigmented ones, while the others were regular translucent prostheses. No complications occurred with either type. Even when applied in adults, the traditional translucent prosthesis gives the unpleasent impression of hydrocele. In pediatric cases, this unesthetic appearance is enhanced because of the disproportion between the scrotum and the size of the prosthesis. The cosmetic appearances of these scrota have been partially improved by the use of colored, opaque prostheses. Offprint requests to: F. Ferro  相似文献   
32.
33.
34.
35.
36.
Torpor is a naturally occurring, hypometabolic, hypothermic state engaged by a wide range of animals in response to imbalance between the supply and demand for nutrients. Recent work has identified some of the key neuronal populations involved in daily torpor induction in mice, in particular, projections from the preoptic area of the hypothalamus to the dorsomedial hypothalamus (DMH). The DMH plays a role in thermoregulation, control of energy expenditure, and circadian rhythms, making it well positioned to contribute to the expression of torpor. We used activity-dependent genetic TRAPing techniques to target DMH neurons that were active during natural torpor bouts in female mice. Chemogenetic reactivation of torpor-TRAPed DMH neurons in calorie-restricted mice promoted torpor, resulting in longer and deeper torpor bouts. Chemogenetic inhibition of torpor-TRAPed DMH neurons did not block torpor entry, suggesting a modulatory role for the DMH in the control of torpor. This work adds to the evidence that the preoptic area of the hypothalamus and the DMH form part of a circuit within the mouse hypothalamus that controls entry into daily torpor.SIGNIFICANCE STATEMENT Daily heterotherms, such as mice, use torpor to cope with environments in which the supply of metabolic fuel is not sufficient for the maintenance of normothermia. Daily torpor involves reductions in body temperature, as well as active suppression of heart rate and metabolism. How the CNS controls this profound deviation from normal homeostasis is not known, but a projection from the preoptic area to the dorsomedial hypothalamus has recently been implicated. We demonstrate that the dorsomedial hypothalamus contains neurons that are active during torpor. Activity in these neurons promotes torpor entry and maintenance, but their activation alone does not appear to be sufficient for torpor entry.  相似文献   
37.
Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 is associated with a wide spectrum of disease, ranging from asymptomatic infection to acute respiratory distress syndrome. Some biomarkers may predict disease severity. Among them, the anti-SARS-CoV-2 antibody response has been related to severe disease. The aim of this study was to assess the correlation between the anti-SARS-CoV-2 serological response and COVID-19 outcome. Demographic, clinical, and biological data from nasopharyngeal-PCR confirmed COVID-19 hospitalized patients were prospectively collected between April and August 2020 at our institution. All patients had serial weekly serology testing for a maximum of three blood samples or until discharge. Two different serological assays were used: a chemiluminescent assay and an in-house developed Luminex immunoassay. Kinetics of the serological response and correlation between the antibody titers and outcome were assessed. Among the 70 patients enrolled in the study, 22 required invasive ventilation, 29 required non-invasive ventilation or oxygen supplementation, and 19 did not require any oxygen supplementation. Median duration of symptoms upon admission for the three groups were 13, 8, and 9 days, respectively. Antibody titers gradually increased for up to 3 weeks since the onset of symptoms for patients requiring oxygen supplementation with significantly higher antibody titers for patients requiring invasive ventilation. Antibody titers on admission were also significantly higher in severely ill patients and serology performed well in predicting the necessity of invasive ventilation (AUC: 0.79, 95% CI: 0.67–0.9). Serology testing at admission may be a good indicator to identify severe COVID-19 patients who will require invasive mechanical ventilation.  相似文献   
38.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the clinical outcomes of vitrectomy with induction of posterior vitreous detachment for the treatment of optic disc...  相似文献   
39.
From January 1976 to October 1986, 107 cases of esophageal atresia (EA) were admitted to the Neonatal Surgical Unit of the Bambino Gesú Hospital of Rome; 86% of the children had a type III EA. Associated anomalies were present in 47%; they were multiple in 18%. Cardiological malformations were the most frequent followed by digestive, skeletal, urological, and chromosomal aberrations. Surgical treatment was attempted in all children except 3, who died before surgical correction, in an effort to perform an end-to-end anastomosis in a single layer through a transpleural approach. According to the results, children were divided into two groups of 50 patients each: group 1 (1976–1981); and group 2 (1981–1986). Anastomosis was possible in 69% of children (68.7% in group 1, 69.3% in group 2). After 1983, gastrostomy fell into gradual disrepute and a transanastomotic tube was used. Immediate complications were seen in 36.6% of cases; in no case did recurrence of the tracheoesophageal fistula occur. The overall mortality decreased from 50% (group 1) to 30% (group 2). In the two periods considered, the mortality according to Waterston's risk classes was 28.5% 5,8% (class A), 42.1% 11.7% (class B), 82.3% 68.7% (class C). Of a total of 41 deaths, 47% were due to severe associated malformations: bronchopneumopathy or prematurity seemed to have less importance in establishing the prognosis.Offprint requests to: P. Bagolan  相似文献   
40.
BACKGROUND: Giant myomas of the uterus are uncommon, particularly in developed countries. CASE: This report illustrates a case of a woman with a bilobated giant myoma of the uterus weighed in total 27.7 kg. The patient had an abdominal distension first noted 18 months before and the personal history evidenced difficulties in walking and tiredness. Abdominal hysterectomy and bilateral salpingo-oophorectomy were carried out. CONCLUSIONS: The knowledge of the different clinical manifestation of these myomas may allow to face that with adequate perioperative care, in order to assure a carefully and successfully surgery, although sometimes a benign pathology may be not easy to suspect in a first time.  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