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   10154篇
  免费   880篇
  国内免费   166篇
医药卫生   11200篇
  2024年   16篇
  2023年   245篇
  2022年   294篇
  2021年   483篇
  2020年   308篇
  2019年   342篇
  2018年   452篇
  2017年   467篇
  2016年   439篇
  2015年   377篇
  2014年   522篇
  2013年   1482篇
  2012年   414篇
  2011年   447篇
  2010年   380篇
  2009年   376篇
  2008年   394篇
  2007年   382篇
  2006年   340篇
  2005年   308篇
  2004年   289篇
  2003年   267篇
  2002年   212篇
  2001年   179篇
  2000年   182篇
  1999年   126篇
  1998年   132篇
  1997年   125篇
  1996年   113篇
  1995年   109篇
  1994年   92篇
  1993年   87篇
  1992年   70篇
  1991年   87篇
  1990年   66篇
  1989年   53篇
  1988年   65篇
  1987年   54篇
  1986年   41篇
  1985年   76篇
  1984年   64篇
  1983年   34篇
  1982年   43篇
  1981年   36篇
  1980年   37篇
  1979年   24篇
  1978年   16篇
  1977年   18篇
  1975年   8篇
  1974年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
PurposeTo assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications.Materials and MethodsSix academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11–94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1–5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications.ResultsBalloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred.ConclusionsBalloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).  相似文献   
2.
PurposeTo explore the safety and effectiveness of bronchial artery (BA) embolization (BAE) in children with pulmonary hemorrhage.Materials and MethodsBetween February 2016 and February 2019, 41 patients (median age, 4 y; interquartile range, 2.3-8 y; median weight, 17.6 kg; interquartile range, 12.3–23.6 kg) underwent BAE. The indication of BAE included massive hemoptysis in 10 patients (24.4%), recurrent hemoptysis in 18 patients (43.9%), and refractory anemia in 13 patients (31.7%). The main etiology of pulmonary hemorrhage included pulmonary hemosiderosis (58.5%), congenital heart disease (17.1%), and infection (14.6%). A retrospective review was conducted of clinical outcomes of BAE.ResultsThere were 44 embolization sessions, with a total of 137 embolized vessels. Pulmonary hemorrhage was caused by BAs in 30 cases, nonbronchial systemic arteries plus BAs in 10, and nonbronchial systemic arteries in 1. Embolic particles were used in 30 cases (24 polyvinyl alcohol [PVA] and 6 microsphere), coils in 9 cases, and particles plus coils in 5 cases (4 PVA and 1 microsphere). Technical success (ability to embolize abnormal vessel) was achieved in 97.6% of patients (40 of 41), and clinical success (complete or partial resolution of hemoptysis within 30 days of embolization) was achieved in 90.2% (37 of 41). There was 1 procedure-related complication (2.4%) of cerebral infarction and 1 death from multiple-organ dysfunction (2.4%). Bleeding-free survival rates at 6, 12, 24, and 36 months were 92.5%, 83.9%, 83.9%, and 70.8%, respectively.ConclusionsBAE is a safe and effective procedure in children with pulmonary hemorrhage.  相似文献   
3.
The “restricted areas” provisions of the Northern Territory Liquor Act constitute a preventative policy aimed at reducing the effects of alcohol abuse, particularly on Aboriginal communities. Under the provisions, communities can apply to be declared “dry” or semi-restricted with respect to liquor. Since their inception in 1979, the provisions have given rise to continuing controversy. This paper addresses some of the issues associated with the controversy. Patterns of alcohol consumption on “dry”, semi-restricted and unrestricted communities are compared, and the incidence of apprehension for public drunkenness before and after restricted area declarations is examined. The paper also discusses the provisions under which vehicles implicated in acts of illicit “grog-running” are forfeited to the NT Government. It is concluded that the restricted area provisions are associated with reduced levels of alcohol consumption and apprehensions for drunkenness, and are therefore beneficial in outcome. However, it is also argued that at present the provisions are flawed in that, while some aspects serve to promote community control over alcohol consumption, other elements have the effect of undermining community control and responsibility.  相似文献   
4.
Introduction and Aims. Different self‐report methods tend to produce different estimates of alcohol consumption. The present study compares differences in rates and risk levels based on responses to a modified version of the Daily Drinking Questionnaire (m‐DDQ) and quantity‐frequency (QF) questions. Design and Methods. The sample comprised 2082 university students, 61% of whom were female and 39% male with a mean age of 23.5 years. An email containing an online link to a brief six‐question survey was emailed to students enrolled in participating faculties at the University of Wollongong, Australia. Current drinkers completed m‐DDQ and QF questions about alcohol consumption. Results. QF methods identified significantly lower estimates of consumption (Mean = 9.15, SD = 12.51) compared with m‐DDQ (Mean = 13.06, SD = 14.07). Allocation to risk categories based on the Australian Alcohol Guidelines were conducted for both the m‐DDQ and QF methods. Almost twice as many students were found to be drinking at levels considered risky using the m‐DDQ method compared with QF. In addition, the relative rank order of participants varied significantly between the two methods. Discussion and Conclusions. The m‐DDQ method identified higher rates of drinking and categorised almost twice as many individuals into risky categories of drinking compared with QF. Such variations have major implications for identification of risk groups in health promotion or prevention programs.[Utpala‐Kumar R, Deane FP. Rates of alcohol consumption and risk status among Australian university students vary by assessment questions. Drug Alcohol Rev 2009]  相似文献   
5.
1Introduction Substanceabusecontinuestobeamongthemostsevereso cialandcostlyhealthproblemsdevastatingindividualsandtheir familiesintheUnitedStates.Initssimplestdefinition,sub stanceabuseisthecontinueduseofalcoholorotherdrugsde spiteknowledgeofhavingapersistentsocial,vocational,psy chologicalorphysicalproblemthatiscausedorexacerbatedby theuseofalcoholorotherdrugs(DSMIV TR,1994).All drugsofabuse,includingalcohol,aretoxicandcannegatively impacteverysysteminthehumanorganism.Protractedsub stance…  相似文献   
6.
Alterations occurring in the neurons of rat sensorimotor cortex 1, 2, and 4 months after a 4-month alcohol intoxication and 1 and 4 months after a 1-year alcoholization are studied by the methods of Nissl and Golgi. Pronounced dystrophic changes in cortical neurons and dendrites as well as reparative processes in the cell body are revealed 1 month after a 4-month intoxication. The recovery period for the upper cortical layer neurons (phylogenetically younger) is faster than that of neurons from the lower layers (phylogenetically older), as well as that of hypochromatousvs. hyperchromatous cells. Normalization of dendrite structure is slower than that of the cell body. Four months after a 1-year alcohol intoxication the structure of cortical neurons and dendrites is not restored. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 10, pp. 467–470, October, 1996  相似文献   
7.
8.
Data from a 1988 national drinking survey was cluster analysedto identify different types of male drinkers, to assist in thetargeting of health promotion strategies. Of the five segmentsgenerated by the clustering, one labelled Young Heavy DrinkingMales was identified as the most appropriate target segment,because although they were the segment reporting the highestlevel of alcohol-related problems they were also the segmentmost likely to feel they were drinking too much They were thereforethe segment most likely to be responsive to advertising thatsought to support people who wanted to change their drinkinghabits. They were also the most appropriate target for the longer-termgoal of changing the climate of opinion regarding the acceptabilityof more moderate drinking. Comparisons with two previous clusteranalyses showed a high degree of similarity, suggesting thatclustering is a reliable vehicle for identifying drinker types.  相似文献   
9.
Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students.  相似文献   
10.
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