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   6896篇
  免费   706篇
  国内免费   9篇
耳鼻咽喉   133篇
儿科学   174篇
妇产科学   150篇
基础医学   1044篇
口腔科学   160篇
临床医学   786篇
内科学   1391篇
皮肤病学   118篇
神经病学   517篇
特种医学   223篇
外科学   956篇
综合类   212篇
预防医学   691篇
眼科学   182篇
药学   371篇
中国医学   10篇
肿瘤学   493篇
  2021年   118篇
  2020年   62篇
  2019年   90篇
  2018年   107篇
  2017年   95篇
  2016年   105篇
  2015年   121篇
  2014年   154篇
  2013年   206篇
  2012年   366篇
  2011年   320篇
  2010年   192篇
  2009年   166篇
  2008年   282篇
  2007年   330篇
  2006年   278篇
  2005年   257篇
  2004年   264篇
  2003年   251篇
  2002年   214篇
  2001年   235篇
  2000年   227篇
  1999年   208篇
  1998年   77篇
  1997年   78篇
  1996年   66篇
  1995年   50篇
  1994年   53篇
  1993年   57篇
  1992年   155篇
  1991年   164篇
  1990年   162篇
  1989年   157篇
  1988年   155篇
  1987年   128篇
  1986年   146篇
  1985年   140篇
  1984年   121篇
  1983年   128篇
  1982年   64篇
  1980年   57篇
  1979年   84篇
  1978年   70篇
  1977年   51篇
  1976年   58篇
  1975年   52篇
  1974年   68篇
  1973年   54篇
  1971年   56篇
  1970年   50篇
排序方式: 共有7611条查询结果,搜索用时 15 毫秒
1.
The aim of the project was to determine whether the rate of contaminant blood cultures could be reduced by using a team of dedicated phlebotomists. Comparisons were made between adult patients requiring blood cultures for suspected bacteremia on medical and surgical units before and after the introduction and withdrawal of a dedicated blood culture team. The results showed that a significant reduction in the contaminant blood culture rate was achieved by the blood culture team (P < 0.001; chi(2) test). Therefore, in our experience, the rate of contaminant blood cultures can be reduced in a teaching hospital by using a team of dedicated phlebotomists. Calculations made with our data and those published by others suggest that cost savings from reducing false-positive blood cultures are greater than the cost of the blood culture team.  相似文献   
2.
Forty-six (85%) basal cell and eight (15%) squamous cell carcinomas of the eyelids were treated with electron beams between 1963 and 1983. Lesion sizes ranged from microscopic to 4 cm, with 28 lesions larger than 1 cm. Thirty-eight lesions were treated with radiotherapy after incisional biopsy, and 16 were treated after excisional biopsy (specimens showed positive margins). Doses varied from 45 to 72 Gy, with daily fractions ranging from 2.12 to 4.0 Gy. There were six disease recurrences (10.9%): three in the treatment field and three at the treatment margin. Four of six recurrences were subsequently controlled by limited surgical excision and repair with preservation of the eye, whereas the other two required enucleation. Treatment sequelae such as skin atrophy, telangiectasis, and cosmetic results were evaluated in terms of radiotherapy parameters, pretreatment surgery, and size of the lesion. In 44 patients, the overall cosmetic result was judged as good to excellent, five patients had a mild to modest degree of deformity, and five had significant deformity. Such deformity was usually associated with tumor destruction or previous surgery. No major complications were noted.  相似文献   
3.
4.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence.  相似文献   
5.
6.
7.
This paper examines the equality of utilization for equal need and equity of out-of-pocket expenditure for health services in a large urban area in Thailand. Data from a household health interview survey were used to explore patterns of perceived morbidity, utilization of various treatment sources, and out-of-pocket payment. Financial access to health care, as reflected in medical benefit/insurance cover, appeared to influence reported illness and hospitalization rates. Gross lack of access to health care amongst lower socio-economic groups was not the main problem in this densely populated urban area because people could choose and use alternative health services according to their ability and willingness to pay. The corollary, however, was an inequitable pattern of out-of-pocket health expenditure by income quintile and per capita. The underprivileged were more likely to pay out of their own pocket for their health problems, and to pay out of proportion to their household income when compared with more privileged groups. Furthermore, the underprivileged were least likely to be covered by government health benefit schemes, in contrast in particular to civil servants, who paid less out of pocket and did not contribute to their medical benefit fund. The private health sector (private clinics and private hospitals) was the major provider of health care to urban dwellers for both outpatient and inpatient services. Policy options for the short and long term to improve the equity of payment systems for health care are discussed.  相似文献   
8.
A rural hospital elective in a diploma nursing program is described. A need and opportunity for this unique practicum was identified in a Canadian province where one-third of the acute care beds are in hospitals of under 100 beds, located primarily in towns outside of metropolitan areas. The six week course offers students 35 hours of classroom content focusing on rural health care concepts plus a 150 hour practicum in one of three participating hospitals. The course is seen as unique in that it focuses on rural health care and is offered within the context of a diploma nursing program. Vive student outcomes are identified: awareness of the differences between rural and urban health care; integration of knowledge and experience from previous nursing courses as it relates to the rural context; increasing understanding of how rural population groups affect health care delivery; awareness of rural employment opportunities; and, preparation for the graduate role. A shared vision and collaborative effort on the part of the School of Nursing, the rural hospitals and the host communities has been necessary to establish and maintain such a course.  相似文献   
9.
n = 69) normal; Group B (n= 29), abnormal, severe defects; Group C (n= 56), abnormal, mild–moderate defect. RCA detected 32 defects in Group B: 10 internal carotid (ICA), seven endpoint flaps, two kinks, one dissection; 16 external carotid (ECA), 10 severe endpoint defects and six total occlusion; six common carotid (CCA), five irregular proximal shelfs, one web. Thirty of 32 defects were successfully repaired as confirmed by normal repeat RCA studies; one ECA defect was not repaired and the ICA dissection was irreparable. In Group C, 67 mild–moderate defects were identified, but not corrected. These included <30% stenosis in the ICA (12), ECA (18), CCA (24), and vein patch corrugation or irregularity (13). For the entire series the postoperative ICA occlusion rate was 2% (3/154), stroke rate 2.6% (4/154), and a subsequent >50% restenosis rate of 7% (11/154). The yield from routine carotid completion arteriograms was significant, with 19% of studies identifying a severe defect that required repair. Although the difference in stroke rates and restenosis between the different groups did not reach statistical significance, patients with normal intraoperative arteriograms initially or after correction of a significant RCA defect had no early carotid occlusion (p= 0.05, Fisher's exact test) compared to patients with residual RCA defects. All early carotid occlusions occurred in patients with unrepaired defects. We conclude that RCA is an important method of quality control after CEA and exerts a subtle, but real, reduction in postoperative complications.  相似文献   
10.
Phagocytic leukocytes were separated from the peripheral blood of chickens using a one-step Percoll density gradient technique. Heterophils recovered from two fractions of the gradient were of 96.9 to 99.8% purity and were fully viable and functional, as demonstrated by their capacity to phagocytose latex beads and staphylococci. Adherent mononuclear cells were cultured from specific gradient fractions and shown to phagocytose staphylococci.  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