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   312篇
  免费   17篇
  国内免费   39篇
耳鼻咽喉   4篇
儿科学   32篇
基础医学   21篇
口腔科学   7篇
临床医学   56篇
内科学   65篇
皮肤病学   5篇
神经病学   4篇
特种医学   79篇
外科学   24篇
综合类   8篇
预防医学   10篇
眼科学   4篇
药学   33篇
肿瘤学   16篇
  2023年   1篇
  2021年   2篇
  2020年   2篇
  2019年   4篇
  2018年   3篇
  2017年   5篇
  2016年   2篇
  2015年   8篇
  2014年   8篇
  2013年   13篇
  2012年   8篇
  2011年   4篇
  2010年   14篇
  2009年   7篇
  2008年   7篇
  2007年   30篇
  2006年   12篇
  2005年   11篇
  2004年   9篇
  2003年   2篇
  2002年   3篇
  2001年   4篇
  2000年   6篇
  1999年   4篇
  1998年   20篇
  1997年   20篇
  1996年   24篇
  1995年   10篇
  1994年   20篇
  1993年   10篇
  1992年   11篇
  1991年   6篇
  1990年   7篇
  1989年   12篇
  1988年   8篇
  1987年   4篇
  1986年   8篇
  1985年   9篇
  1984年   4篇
  1983年   4篇
  1982年   6篇
  1981年   6篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   3篇
  1975年   1篇
  1967年   1篇
  1965年   1篇
  1959年   1篇
排序方式: 共有368条查询结果,搜索用时 15 毫秒
81.
82.
Lethal neonatal Menkes' disease with severe vasculopathy and fractures   总被引:1,自引:0,他引:1  
A male neonate presented with an acute onset of severe intra-abdominal bleeding, haemorrhagic shock and multiple fractures leading to death on d 27. Menkes' disease was diagnosed at autopsy and confirmed by copper accumulation studies on cultured fibroblasts. Such an early onset of fatal complications in this condition has not been previously reported. New insights into the pathogenesis of Menkes' disease provided by DNA mutation analysis and difficulties in neonatal diagnosis are discussed. Menkes' disease should be considered in male infants with pathological fractures and other signs of connective tissue disease, even in the neonatal period.  相似文献   
83.
84.
Nineteen infants who were graduates from special care baby units underwent two overnight tape recordings of oxygen saturation (SaO2) and breathing movements; one during an upper (n = 12) or lower (n = 7) respiratory tract infection and the other when free of infection. Baseline SaO2 was lower during infection (median 99.6 vs 100%, p less than 0.01), with four patients having values (84.3-95.5%) below the normal lower limit for full-term infants (97%). The median number of apnoeic pauses was also lower during respiratory tract infection (4.7 vs 15.7/h, p less than 0.02). The median number of episodic desaturations (SaO2 less than or equal to 80%) did not change significantly (1.3 vs 1.9/h, p greater than 0.05), with the exception of one patient who had extremely increased values during infection for both apnoeic pauses (63/h) and desaturations (112/h). No infant, however, was considered clinically hypoxaemic. Clinically unsuspected hypoxaemia may thus occur during respiratory tract infection in a proportion of infants graduating from special care baby units. Such hypoxaemia may have potentially deleterious effects.  相似文献   
85.
A prospective study was undertaken to identify possible factors related to the duration of breast feeding. Two hundred and thirty-eight mothers who had delivered normal single babies with birth weights greater than 2.5 kg and had initiated breast feeding were randomly selected at the maternity hospital, Hospital de Clinicas de Porto Alegre, Brazil, and followed by mail questionnaires until termination of breast feeding, or until the end of the first year. If no reply was received, telephone contact or home visits were made. The group of mothers who stopped breast feeding prior to the end of the third month was compared with those who extended breast feeding beyond three months with respect to socioeconomic, biological, environmental, medical and psychological factors. The variables with a significant coefficient of association with early termination of breast feeding were maternal education, past experience with breast feeding, help of a maid, help with housework provided by a relative, breast feeding orientation during prenatal care and encouragement from the husband. These factors act simultaneously, with interactions among them.  相似文献   
86.
As antimicrobial-resistant microbes become increasingly common and a significant global issue, novel approaches to treating these infections particularly in those at high risk are required. This is evident in people with cystic fibrosis (CF), who suffer from chronic airway infection caused by antibiotic resistant bacteria, typically Pseudomonas aeruginosa. One option is bacteriophage (phage) therapy, which utilises the natural predation of phage viruses upon their host bacteria. This review summarises the essential and unique aspects of the phage-microbe-human lung interactions in CF that must be addressed to successfully develop and deliver phage to CF airways. The current evidence regarding phage biology, phage-bacterial interactions, potential airway immune responses to phages, previous use of phages in humans and method of phage delivery to the lung are also summarised.  相似文献   
87.
88.
89.
Background: The Müller cell, the major glial cell in the retina, may be important in diabetes. The purpose of this project was to examine the localisation of glutamine synthetase in control and diabetic Müller cells and to determine whether the number of Müller cells is altered during diabetes. We also examined whether two experimental treatments of diabetes, aminoguanidine and ramipril, ameliorated these changes. Methods: Normal Sprague‐Dawley rats rendered diabetic by a single injection of streptozotocin (50 mg/kg) were treated with either aminoguanidine, ramipril or standard water. Following 12 weeks, animals were sacrificed, their eyes removed and the retinae processed for glutamine synthetase immunocytochemistry. The level of glutamine synthetase was quantified in control and diabetic animals and the number of Müller cells counted for each of the treatment groups. Results: In all retinae examined, glutamine synthetase labelled Müller cells along their entire cellular extent and endfeet were more intensely labelled. Following 12 weeks of diabetes, there was a small increase in the level of glutamine synthetase labelling in somata and endfeet compared with controls (ANOVA, P < 0.05). The number of Müller cells was increased following 12 weeks of diabetes (ANOVA, P < 0.0001). This effect was ameliorated by treatment with ramipril and aminoguanidine. Conclusions: These data suggest that Müller cells are altered in number following 12 weeks of diabetes. Moreover, the two experimental treatments were beneficial in preventing this change in Müller cells. Further work is required to establish the mechanisms underlying the change to Müller cells during diabetes.  相似文献   
90.
PURPOSE: Radio frequency treatment in cardiology generates short acute pain during the heating process. The present study evaluates two techniques used for sedation/analgesia for this procedure. METHODS: Two groups of 20 patients each were studied prospectively. Patients were randomized to receive sedation for the procedure using either a patient-controlled analgesia device with remifentanil (Group R), or a target controlled infusion of propofol (Group P). Patients in Group R had a basal infusion of remifentanil 0.02-0.04 microg x kg(-1) x min(-1) with self administered bolus doses of 0.3 microg x kg(-1) i.v. every minute as required, with a delivery time greater than 30 sec. Patients in Group P had an initial plasma target concentration set at 3-4 microg x mL(-1). RESULTS: Sedation scores were significantly higher in Group P, and two patients required supplementation with remifentanil and insertion of an laryngeal mask airway. Pain scores were higher in Group R, and two patients experienced muscular rigidity, one with transient apnea. Systolic blood pressure decreased significantly in Group P, and at the end of the procedure, PaCO(2) values were higher in that group (P < 0.01). Recovery time was significantly longer in Group P. Patient and physician satisfaction scores were similar in the two groups. CONCLUSIONS: A basal infusion of remifentanil plus remifentanil patient controlled analgesia and target controlled infusion of propofol were adequate but not optimal techniques for sedation/analgesia for radio frequency treatment of atrial flutter.  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