首页 | 官方网站   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   475篇
  免费   30篇
  国内免费   6篇
医药卫生   511篇
  2023年   3篇
  2022年   8篇
  2021年   16篇
  2020年   6篇
  2019年   5篇
  2018年   14篇
  2017年   7篇
  2016年   8篇
  2015年   12篇
  2014年   16篇
  2013年   20篇
  2012年   13篇
  2011年   10篇
  2010年   30篇
  2009年   21篇
  2008年   21篇
  2007年   26篇
  2006年   17篇
  2005年   9篇
  2004年   14篇
  2003年   8篇
  2002年   7篇
  2001年   11篇
  2000年   10篇
  1999年   24篇
  1998年   29篇
  1997年   19篇
  1996年   16篇
  1995年   6篇
  1994年   11篇
  1993年   10篇
  1992年   6篇
  1991年   7篇
  1990年   6篇
  1989年   14篇
  1988年   8篇
  1987年   3篇
  1986年   2篇
  1985年   5篇
  1984年   4篇
  1983年   5篇
  1981年   2篇
  1980年   1篇
  1979年   5篇
  1978年   3篇
  1977年   6篇
  1976年   2篇
  1975年   2篇
  1971年   1篇
  1967年   1篇
排序方式: 共有511条查询结果,搜索用时 0 毫秒
1.
2.
Needle core biopsy guided with mammography: a study of cost- effectiveness   总被引:2,自引:0,他引:2  
Lindfors  KK; Rosenquist  CJ 《Radiology》1994,190(1):217
  相似文献   
3.
4.
The complete nucleotide sequence of the large polymerase (L) protein of the avian metapneumovirus subgroup C strain Colorado was determined. The L protein gene of avian pneumovirus Colorado isolate (APV-C) was 6173 nucleotides in length from the gene-start to the gene-end and encoded a polypeptide of 2005 amino acids in length. The length of the L protein of APV-C was exactly the same as that of human metapneumovirus (hMPV) and one amino acid longer than the L protein of APV subgroup A. The L protein of APV-C showed 80% amino acid identity with the L protein of hMPV, but only 64% amino acid identity with the L protein of APV-A. The nucleotide and deduced amino acid sequences were compared with the corresponding sequences of eleven other paramyxoviruses. All six domains characteristic of paramyxovirus L proteins were also observed in the L protein of APV-C. All the polymerase core motifs in domain III were conserved to nearly 100% in the metapneumoviruses. Similarly, the putative ATP-binding motif in domain VI was completely conserved among the metapneumoviruses and differed in length, by one intermediate residue, from other paramyxoviruses. Phylogenetic analysis of the different L proteins also revealed a closer relationship between APV-C and hMPV.  相似文献   
5.
This paper describes the tragic case of a young woman who died of cancer of the colon after successfully donating eggs to her younger sister. Although there is no direct link between her operation and the subsequent development of bowel carcinoma, this case imparts a feeling of unease when seen in conjunction with other cases reported during the last few years. It is a reminder that little is known of the long-term consequences of some aspects of assisted conception. Women undergoing ovarian stimulation for themselves or a matched recipient have the right to be advised, in an agreed format, that there is some concern about unproven potential risks from the stimulatory drugs. The safety of egg donors must assume priority over all other considerations, including lack of donors or any moral position. The recent decision by the Human Fertilisation and Embryology Authority (HFEA) to withdraw any form of payment or recompense to egg donors does not seem to us to be based on a balance of scientific advances, patient needs and the ethics of gamete supply. They state that the intention to withdraw payments was implicit in the 1990 Human Fertilisation and Embryology (HFE) Act. However the Act was based on the Warnock report made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility drugs had not yet caused any unease. The Act provided the HFEA with discretionary powers to issue directions so that the future policies would be consistent with any emerging new medical evidence. It is imperative that the HFEA provide convincing evidence on how the current policy of payment to donors harms society, donors or recipients, and how in the UK the new policy will improve medical practice in assisted conception. Successful pilot studies must precede the implementation of any new policy. Failure to do this could cause irreversible harm to the practice of assisted conception using donor gametes, which will ultimately be against the basic aims of the 1990 HFE Act.   相似文献   
6.
Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care  相似文献   
7.
One hundred patients undergoing abdominal surgery were included in this prospective study. The role of local application of Betadine, use of synthetic sutures, and use of low pressure subcutaneous suction drainage were evaluated in preventing post-operative wound infection. The infection rate was 15 per cent with Betadine, 15.4 per cent with prolene, 20 per cent with subcutaneous suction drainage and 30.8 per cent in the control group.KEY WORDS: Surgical wound infection, Betadine, Sutures, Infection control  相似文献   
8.
Serving personnel of Armed Forces admitted with tuberculosis between Apr 1996–1999 were evaluated for co-infection of tuberculosis and HIV. Sixty (1.06%) of tuberculosis patients were found to be HIV positive. Initial test was done by spot kits and subsequently confirmed by ELISA on two different samples. Majority of the cases were in sexually active age group 48 (80%). Alcohol and smoking was associated in 80% cases. Thirty six (60%) were sputum smear positive for AFB. Twenty eight (46.7%) gave history of exposure to sex workers. Family members were not available for study. Sero prevalence of HIV in association with tuberculosis is less in Armed Forces compared to civil population.KEY WORDS: HIV, Seroprevalence, Tuberculosis  相似文献   
9.
BACKGROUND: The aim of this study was to compare the effectiveness of an intensive asthma education program (group B) with that of a standard asthma education program (group A). METHODS: A prospective randomized single blinded study was conducted in the pediatric department of a public hospital in Hong Kong. Children aged 2-15 years admitted to the pediatric department with an acute attack of asthma were recruited. A standard asthma education program (group A) or an intensive asthma education program (group B) for children were offered. The main outcome measures include the number of visits to the emergency department and the number of hospitalization for asthma during the 3 month follow-up period. RESULTS: A total of 45 children were in group A and 55 in group B. Group B had statistically significant reductions in the number of visits to the emergency department and the number of hospitalizations. Drug compliance was also significantly improved in group B. Parents' satisfaction rate was also higher in group B. CONCLUSION: The intensive asthma education program might be more cost effective than the standard asthma education program in the management of asthmatic children admitted to hospital in Hong Kong.  相似文献   
10.
Interfacial adhesion of thick NiTi coating on substrate stainless steel is investigated here. NiTi coating was deposited on the substrate by using the thermal plasma spraying method. Deposition of NiTi coating was carried out by using various levels of input power under an Ar atmosphere. Multiple coating layers were deposited on the stainless steel surface for a specific thickness. The cross-section of the plasma-sprayed samples were prepared and characterized by using various techniques. The hardness of the coating layers on the surface and cross-section was examined. The thickness of the coating increased with the increase in power. No cracks were detected in the interface for the NiTi coating deposited at 12 kW power. However minor pores were observed at some regions along the interface at the sample prepared at 9 kW power. A good-quality coating layer was formed at the interface of the substrate. Primary phases of austenite and martensite were confirmed from the EBSD and XRD investigations. There was the presence of intermetallic and oxide phases in the coating layers. A less heat-affected zone of 10 µm of along the interface was confirmed without any diffusion of elements from the substrate to the coating layers. There was homogenous distribution elemental composition of Ni and Ti throughout the coating layers.  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-23

京公网安备 11010802026262号