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   1112篇
  免费   60篇
  国内免费   16篇
耳鼻咽喉   18篇
儿科学   67篇
妇产科学   22篇
基础医学   111篇
口腔科学   11篇
临床医学   89篇
内科学   184篇
皮肤病学   14篇
神经病学   64篇
特种医学   246篇
外科学   128篇
综合类   35篇
预防医学   75篇
眼科学   8篇
药学   72篇
中国医学   1篇
肿瘤学   43篇
  2021年   15篇
  2020年   9篇
  2019年   4篇
  2018年   5篇
  2017年   5篇
  2016年   18篇
  2015年   22篇
  2014年   18篇
  2013年   26篇
  2012年   23篇
  2011年   34篇
  2010年   36篇
  2009年   36篇
  2008年   25篇
  2007年   36篇
  2006年   41篇
  2005年   36篇
  2004年   26篇
  2003年   35篇
  2002年   32篇
  2001年   30篇
  2000年   30篇
  1999年   26篇
  1998年   52篇
  1997年   56篇
  1996年   41篇
  1995年   28篇
  1994年   43篇
  1993年   26篇
  1992年   13篇
  1991年   17篇
  1990年   14篇
  1989年   38篇
  1988年   28篇
  1987年   22篇
  1986年   29篇
  1985年   23篇
  1984年   24篇
  1983年   20篇
  1982年   18篇
  1981年   33篇
  1980年   10篇
  1979年   12篇
  1978年   14篇
  1977年   10篇
  1976年   12篇
  1975年   12篇
  1974年   4篇
  1973年   5篇
  1970年   4篇
排序方式: 共有1188条查询结果,搜索用时 661 毫秒
111.
A 6‐week‐old infant presenting with near‐drowning was medically paralysed and ventilated on admission. Status epilepticus was found on cerebral function monitoring, without which the diagnosis would have been missed or delayed for many hours. This case illustrates the value of cerebral function monitoring for patients in intensive care, where clinical signs of seizure activity are frequently masked by paralysis and sedation. Conclusion: Limited availability of electroencephalogram (EEG) and cerebral function monitoring (CFM) in paediatric intensive care may inadvertently delay diagnosis and appropriate treatments and so adversely affect outcomes. We propose that round‐the‐clock cerebral function and/or EEG monitoring should be available in all centres that provide paediatric intensive care.  相似文献   
112.
113.
114.
Traumatic brain injury (TBI) is frequently accompanied by a systemic inflammatory response secondary to multiple trauma, shock, or infections. This study investigated the impact of sustained systemic inflammation on cerebral hemodynamics and metabolism in ovine traumatic brain injury. Fifteen sheep were investigated for 14 hours. Head injury was induced with a nonpenetrating stunner in anesthetized, ventilated animals. One group (TBI/Endo, n = 6) subsequently received a continuous endotoxin infusion for 12 hours, whereas a second group (TBI, n = 6) received the carrier. Three instrumented animals served as sham controls. Head impact significantly increased intracranial pressure from 9 +/- 4 mm Hg to 21 +/- 15 mm Hg (TBI/Endo) and from 10 +/- 3 mm Hg to 24 +/- 19 mm Hg (TBI) (means +/- SD). Internal carotid blood flow increased and cerebral vascular resistance decreased (P < 0.05) during the hyperdynamic inflammatory response between 10 and 14 hours in the TBI/Endo group, whereas these parameters were at baseline level in the TBI group. Intracranial pressure remained unchanged during this period, but increased during hypercapnia. The CMRO2, PaCO2, and arterial hematocrit values were identical among the groups between 10 and 14 hours. It is concluded that chronic endotoxemia in ovine traumatic brain injury was associated with cerebral vasodilation uncoupled from global brain metabolism. Different mechanisms appear to induce cerebral vasodilation in response to inflammation and hypercapnia.  相似文献   
115.
116.
Immunohistochemical techniques have become commonplace adjunctive aids in anatomic pathology. Although much has been written describing modifications of the basic techniques, sensitivity, and specificity of reagents, little has been published regarding the interlaboratory variability in immunostain results on a given test sample. The Cell Markers Survey of the College of American Pathologists was organized to address this question of interlaboratory variability and to disseminate information on the techniques and reagents currently available.  相似文献   
117.
118.
M17: a novel gene expressed in germinal centers   总被引:1,自引:0,他引:1  
Germinal centers are histologically distinct structures thatform within the draining lymphoid tissues following immunizationwith T cell-dependent antigens. Here, antigen-specific B cellstransform the lymphoid follicle into a site of intense B cellproliferation, differentiation and selection. To understandthe molecular basis for these cellular events, we sought toisolate germinal center B cell-specific genes using subtractivecDNA libraries derived from FACS-sorted (CD45R/B220+, lgD,Thy1.2) lymph node B cells of immunized mice. A novelgene isolated from this library, designated M17, was found tobe transcribed in spleen and, to a lesser extent, bone marrow.Strikingly, only PNA+ (germinal center) but not PNA splenicB cells express M17. Germinal center-specific expression ofM17 was confirmed by staining of histoiogical sections of spleenwith an antiserum raised against a glutathione-S-transferase-M17fusion protein. The M17 gene comprises four exons spanning 13.2kb, and encodes a 25 kDa cytoplasmic protein of 159 amlno acids.Analysis of the amino acid sequence revealed the presence ofa possible llpid binding domain and multiple potential phosphorylationsites, including a tyrosine-based activation motif. We speculatethat M17 may be a signaling molecule involved in the transductionof signals from the cell surface to the cytoplasm.  相似文献   
119.
BACKGROUND: The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) enrolls almost 50% of the US birth cohort and these children have significantly lower immunization coverage rates than their counterparts not eligible for WIC. In 1994, the Centers for Disease Control and Prevention (CDC) and USDA began a national initiative to increase immunization coverage in low-income children by incorporating immunization-promoting activities into WIC visits (WIC/Immunization linkages). Since 1998, CDC has monitored the WIC/Immunization linkages assessment and referral (with and without the more aggressive strategy of monthly voucher pick-up, client outreach and tracking and parental incentives) and three other immunization supporting activities (computerized systems to assess immunization status, collocation of WIC and immunization services, coordination of WIC and immunization services). METHODS: Through an annual survey of state Immunization and WIC programs, a trend analysis was conducted for years 1998 through 2004 to determine changes in the use and frequency of WIC/Immunization linkage activities. RESULTS: During the 7-year study period, the use of assessment and referral increased from 71% to 94%, monthly voucher pick-up from 24% to 35%, and coordination of WIC and immunization services from 61% to 78% (p<0.0001 for all comparisons) in WIC sites nationwide. The frequency of assessment and referral (at each visit [four or more times/ year] versus certification visits [two times/year]) was reported to decrease during the study period (p<0.0001). Outreach and tracking and collocation of services did not change significantly while the use of parental incentives decreased (p<0.0001). The availability of computers and their use immunization assessment increased during the period. From 2002-2004, the number of states reporting that they base assessment and referral on a single vaccine (diphtheria-tetanus-acellular pertussis) instead of counting multiple vaccines increased from 5 to 10. CONCLUSIONS: Immunization promoting activities, especially those known to be most effective in improving coverage such as monthly voucher pickup, are increasing in WIC. Focusing on effective interventions including supporting activities such as computerized assessment will be essential in meeting Healthy People 2010 infant and childhood immunization coverage goals. In addition, the use of WIC resources can be minimized by encouraging evaluation of diphtheria-tetanus-acellular pertussis coverage as a marker for up to date status, instead of counting all vaccine doses.  相似文献   
120.
A large-scale, randomised, multicentre single-blind clinical trial was conducted to assess the comparative efficacy and tolerance of ofloxacin, trimethoprim and co-trimoxazole in the treatment of uncomplicated urinary tract infection in general practice. A total of 1,069 patients from 76 centres across the UK were enrolled in the study, and randomised to one of the following treatment groups: ofloxacin (200 mg od), trimethoprim (200 mg bd) or co-trimoxazole (trimethoprim 160 mg and sulphamethoxazole 800 mg bd). Each patient received five days of medication. Clinically, ofloxacin was as effective as trimethoprim and co-trimoxazole. However, the bacteriological cure rate was significantly better for ofloxacin, with eradication of the initial causative pathogen by the end of treatment in 92% of patients in the ofloxacin group, compared with 81% for trimethoprim and co-trimoxazole (P = 0.0002). There was also a lower relapse rate for ofloxacin. Ofloxacin was well tolerated: adverse events were reported by 67 (12.4%) patients in the ofloxacin group, compared with 48 (18.7%) patients in the co-trimoxazole group and 37 (13.6%) patients in the trimethoprim group. Ofloxacin can therefore be considered a suitable alternative for the treatment of uncomplicated urinary tract infection.  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