全文获取类型
收费全文 | 1117篇 |
免费 | 43篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 48篇 |
妇产科学 | 32篇 |
基础医学 | 82篇 |
口腔科学 | 15篇 |
临床医学 | 133篇 |
内科学 | 242篇 |
皮肤病学 | 34篇 |
神经病学 | 73篇 |
特种医学 | 257篇 |
外科学 | 48篇 |
综合类 | 28篇 |
预防医学 | 50篇 |
眼科学 | 22篇 |
药学 | 69篇 |
中国医学 | 3篇 |
肿瘤学 | 98篇 |
出版年
2023年 | 5篇 |
2020年 | 5篇 |
2019年 | 8篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 11篇 |
2015年 | 13篇 |
2014年 | 16篇 |
2013年 | 15篇 |
2012年 | 25篇 |
2011年 | 30篇 |
2010年 | 34篇 |
2009年 | 54篇 |
2008年 | 24篇 |
2007年 | 52篇 |
2006年 | 19篇 |
2005年 | 27篇 |
2004年 | 14篇 |
2003年 | 18篇 |
2002年 | 17篇 |
2001年 | 22篇 |
2000年 | 24篇 |
1999年 | 15篇 |
1998年 | 85篇 |
1997年 | 70篇 |
1996年 | 60篇 |
1995年 | 51篇 |
1994年 | 45篇 |
1993年 | 44篇 |
1992年 | 24篇 |
1991年 | 17篇 |
1990年 | 22篇 |
1989年 | 38篇 |
1988年 | 39篇 |
1987年 | 28篇 |
1986年 | 25篇 |
1985年 | 27篇 |
1984年 | 22篇 |
1983年 | 12篇 |
1982年 | 18篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1977年 | 17篇 |
1976年 | 15篇 |
1975年 | 15篇 |
1974年 | 4篇 |
1972年 | 4篇 |
1969年 | 8篇 |
排序方式: 共有1235条查询结果,搜索用时 30 毫秒
81.
Parmigiani G Chen S Iversen ES Friebel TM Finkelstein DM Anton-Culver H Ziogas A Weber BL Eisen A Malone KE Daling JR Hsu L Ostrander EA Peterson LE Schildkraut JM Isaacs C Corio C Leondaridis L Tomlinson G Amos CI Strong LC Berry DA Weitzel JN Sand S Dutson D Kerber R Peshkin BN Euhus DM 《Annals of internal medicine》2007,147(7):441-450
82.
A Levy Bencheton JM Berenger P Del Giudice P Delaunay F Pages JJ Morand 《Journal of the European Academy of Dermatology and Venereology》2011,25(5):599-602
Background Bedbugs (Cimex lectularius) have been feeding on sleeping human beings since prehistory. In Europe, bed bugs were common and endemic until World War II when improved body and home hygiene, and widespread use of insecticides led to almost complete eradication. Current evidence indicates that bedbugs are making a comeback in Europe, USA, Canada and Australia. In our practice in Southern France, we observed several cases within a period of only 1 year. Objectives Based on this experience, we conducted an epidemiological study to evaluate the status of bedbugs in France. Methods During summer 2009, we mailed a short questionnaire to all hospital professors in the CEDEF (Collège des Enseignants de Dermatologie de France) asking four questions: number of suspected diagnosis of bedbugs in the year 2009, and number of certain positive diagnosis, difficulties in treatment, use of a pest control professional for treatment, and finally personal opinion on actual incidence of bedbugs, compared with past years. Results Of the 84 questionnaires sent, there were only 26 responses despite two reminders. The responses were predominantly southern France, probably as a result of intensive immigration and increased travel and trade. Difficulties encountered during diagnosis and treatment are also mentioned. Utilizing the services of entomological experts and pest control professionals is essential. Conclusions France has the same experience regarding the resurgence of bedbugs as several European countries, USA, Canada and Australia, especially the southern regions. This emerging health problem has to be known by dermatologists. A national programme has been launched in France to assess actual incidence and study C. lectularius‐ related diseases. 相似文献
83.
84.
MB Vincent JJ Freitas de Carvalho the Brazilian Headache Care Cooperative Group 《Cephalalgia : an international journal of headache》1999,19(5):520-524
Headaches are common disorders usually examined by nonneurologists. In order to assess how primary headache patients (IHS groups 1, 2, and 3) are generally managed by nonspecialists, 414 patients were asked about their previous headache care. Correct diagnosis had previously been made in only 44.9%, 6.7%, and 26.7% of the migraine, tension-type headache, and cluster headache patients, respectively. The patients underwent 501 investigative procedures motivated by the headache, averaging 1.21 examinations per patient, mostly EEGs. Preventive treatment was largely overlooked irrespective of the headache type. It is concluded that scientific improvements in headache care may be ineffective unless educational programs improve headache knowledge in general. 相似文献
85.
目的:评价经导管置入Amplatzer封堵器治疗继发孔房间隔缺损的治疗效果。方法:①选择2002-08/2006-04在兰州市第一人民医院心外科住院的继发孔型房间隔缺损65例,男26例,女39例;平均年龄(18±8)岁;平均房间隔缺损直径(19.3±7.2)mm。纳入患者对手术方案知情同意。②手术所用封堵器为美国公司的Amplatzer房间隔缺损封堵器,是一种新型的适于关闭二孔型房间隔缺损的装置,它由具有自膨胀性的双盘及连接双盘的腰部三部分组成。双盘状结构恢复记忆形状后可以稳定封堵房间隔缺损的边缘部分,降低残余分流的发生率。③根据选择封堵器大小的方式(即球囊测量或经胸超声心动图直接观察)将患者分为球囊测量组38例和经胸超声心动图测量组27例。均在透视及经胸超声心动图监视下经导管置入Amplatzer封堵器封堵房间隔缺损。同时测量患者缺损扩张直径、封堵器大小,记录X射线透视时间和手术时间。④术后即刻、24h、3个月及1年分别行经胸超声心动图、心电图及X射线检查评价治疗效果。⑤超声心动图显示完全无分流为无分流;残余分流血流宽度≤1mm为微量分流;血流宽度1.0~2.0mm为少量残余分流;血流宽度2~4mm为中量残余分流;血流宽度>4mm为大量残余分流。⑥组间计量资料差异比较采用两个独立样本t检验,组间手术效果比较采用两个独立样本的等级资料秩和检验。结果:①技术成功率:65例房间隔缺损患者,64例封堵器置入成功,技术成功率为98%。②选择封堵器直径:球囊测量组缺损扩张直径为(20.4±6.1)mm,选择的封堵器直径为(21.6±5.7)mm,与经胸超声心动图测量组相近[(22.5±4.3),(25.1±4.9)mm,P>0.05]。③术后残余分流情况:术后即刻经胸超声心动图显示,球囊测量组35例完全无分流,经胸超声心动图组有23例,差异不明显(P>0.05);术后24h,球囊测量组36例完全无分流,经胸超声心动图组有24例,差异不明显(P>0.05);术后3个月,球囊测量组37例完全无分流,经胸超声心动图组有25例,差异不明显(P>0.05);术后1年完成随访的52例患者均未见封堵器移位及房间隔缺损再通。④X射线平片检查:全部显示肺血减少,右心房、室缩小。结论:封堵器直径比球囊测量的房间隔缺损扩张直径大1.0~2.0mm,比超声心动图测量的大2~6mm封堵效果好,成功率高。 相似文献
86.
Van Nostrand D; Abreu SH; Callaghan JJ; Atkins FB; Stoops HC; Savory CG 《Radiology》1988,167(2):495-498
Since indium-111 white blood cell (In-111 WBC) scintigraphy is often used to evaluate for osteomyelitis in bone fractures, it is important to know if noninfected fractures have In-111 WBC uptake. Twenty-seven noninfected closed fracture sites in 19 patients were prospectively evaluated with technetium-99m methylene diphosphonate bone scintigraphy and In-111 WBC scintigraphy. In-111 WBC uptake was present in 41% of the 27 sites. In the 11 positive sites, the In-111 WBC uptake was 1+ (definite but minimal) in 55%, 2+ (moderate) in 36%, and 3+ (marked) in 9%. The visual intensity of the radioactive uptake on In-111 WBC scintigrams relative to that on bone scintigrams was less in 82%, equal in 9%, and greater in 9%. The visual size of the area of uptake on In-111 WBC scintigrams and bone scintigrams was smaller in 36%, equal in 55%, and greater in 9%. Factors that may help distinction of In-111 WBC uptake due to fracture alone from infection associated with fracture are discussed. 相似文献
87.
88.
Health-care case management places pressure on decision makers to adopt treatment strategies that promote economic efficiency and hence profitability. Traditional costeffectiveness analysis (CEA), where the objective is to calculate cost-effectiveness ratios, can better inform decision making in markets where prices and efficacy vary widely. However, the threshold at which a given therapy becomes economically efficient relative to competing therapies is not evident from cost-effictiveness ratios alone.
OBJECTIVE: To illustrate the use of spatial techniques for identifying efficient treatment options, using statin therapy in secondary prevention of coronary heart disease (CHD) as a case study.
METHODS: We used a Markov model of CHD epidemiology and treatment to estimate cost-effectivness of 13 statin regimens versus no therapy in secondary prevention of CHD. Comparative efficacy was assessed using data from a recent trial (CURVES) that included these regimens. Patients were assumed to have a history of CHD with risk factors similar to those observed in the trial. CHD event risk was estimated using new subsequent-event risk equations from the Framingham Heart Study. Effectiveness was measured alternatively as gain in life expectancy and CHD events averted.
RESULTS: At usual starting doses, atorvastatin therapy provided the largest life expectancy gain and CHD event avoidance at the lowest cost per life-year gained ($12,900 and $23,400 for men and women, respectively), followed by simvastatin ($17,700 and $31,700), lovastatin ($18,800 and $33,700), pravastatin ($22,600 and $40,200), and fluvastatin ($23,800 and $42,000). Any desired level of effectiveness can be obtained at lowest cost with atorvastatin.
CONCLUSION: Economic efficiency is enhanced when atorvastatin is used to treat some or all patients requiring statin therapy in secondary prevention of CHD. 相似文献
OBJECTIVE: To illustrate the use of spatial techniques for identifying efficient treatment options, using statin therapy in secondary prevention of coronary heart disease (CHD) as a case study.
METHODS: We used a Markov model of CHD epidemiology and treatment to estimate cost-effectivness of 13 statin regimens versus no therapy in secondary prevention of CHD. Comparative efficacy was assessed using data from a recent trial (CURVES) that included these regimens. Patients were assumed to have a history of CHD with risk factors similar to those observed in the trial. CHD event risk was estimated using new subsequent-event risk equations from the Framingham Heart Study. Effectiveness was measured alternatively as gain in life expectancy and CHD events averted.
RESULTS: At usual starting doses, atorvastatin therapy provided the largest life expectancy gain and CHD event avoidance at the lowest cost per life-year gained ($12,900 and $23,400 for men and women, respectively), followed by simvastatin ($17,700 and $31,700), lovastatin ($18,800 and $33,700), pravastatin ($22,600 and $40,200), and fluvastatin ($23,800 and $42,000). Any desired level of effectiveness can be obtained at lowest cost with atorvastatin.
CONCLUSION: Economic efficiency is enhanced when atorvastatin is used to treat some or all patients requiring statin therapy in secondary prevention of CHD. 相似文献
89.
Ambulatory blood pressure monitoring (ABPM) in adults is proving to be useful. The aim of this study was to determine if ABPM is accurate in the lower blood pressure range encountered in children and, equally important, whether it is acceptable to children. Thirty one children, between the ages of 6 and 18 years, were assessed using an ambulatory blood pressure monitor that uses an auscultatory method. Blood pressure was measured in the contralateral arm with a mercury sphygmomanometer and an oscillometric device at the beginning and end of the study for comparison. Over a blood pressure range of 90-130 mm Hg systolic and 40-80 mm Hg diastolic, a close agreement was found with the sphygmomanometer; the limits of agreement (+/- 2 SD) were 11.6 mm Hg for systolic blood pressure and 13.6 mm Hg for diastolic blood pressure. The bias was less than 1.0 mm Hg. The ambulatory device was worn by all patients for at least 16 hours with an average of 52 recordings per patient. The majority found the device comfortable to wear and were not woken from sleep. 相似文献
90.
Hooijkaas H; Hahlen K; Adriaansen HJ; Dekker I; van Zanen GE; van Dongen JJ 《Blood》1989,74(1):416-422
We investigated whether an indirect nuclear terminal deoxynucleotidyl transferase (TdT) immunofluorescence (IF) assay on single cells present in the cerebrospinal fluid (CSF) is more effective than conventional cytomorphology for early detection or exclusion of (minimal) meningeal leukemic infiltration in patients with a TdT+ malignancy. During a 5- year follow-up study, 1,661 consecutive CSF samples from 113 children with a TdT+ acute lymphoblastic leukemia (ALL) (n = 100), a TdT+ acute nonlymphoblastic leukemia (ANLL) (n = 8), or a TdT+ non-Hodgkin's lymphoma (NHL) (n = 5) were analyzed. In 1,511 (91.9%) of 1,643 evaluable CSF samples, the positive and negative findings of both cytomorphology and the TdT-IF assay were concordant. In 47 (2.9%) samples from 28 patients, the cytomorphology was suspect while the TdT- IF assay was negative; follow-up as long as 58 months revealed no CNS leukemia in any patient. In 85 (5.2%) samples, cytomorphology was negative (n = 70) or suspect (n = 15) but TdT+ cells were detected. RBC contamination seriously hampered evaluation in 31 of these 85 samples. From the remaining 54 TdT+ samples from 29 patients, 40 samples preceded overt CNS leukemia in 20 patients. Two consecutive findings of TdT+ cells in the CSF were always followed by overt CNS leukemia. At initial diagnosis, 11 children had TdT+ cells in their RBC-free CSF. In one of these children, morphology was suspect; a repeated lumbar puncture was positive on both assays. Thus, initial CNS leukemia was diagnosed. In the other ten children, morphology was negative. In six of them, CNS leukemia was diagnosed 2 to 20 months later. In 32 other children examined at initial diagnosis, neither TdT+ cells nor blasts were observed in the CSF. In none of these patients was a CNS leukemia diagnosed after a follow-up of 2.5 to 57 months (median 24 months). In 207 control CSF samples from 58 children with TdT- oncologic, hematologic, or infectious diseases, no TdT+ cells could be detected. The TdT-IF assay is easy to perform and is a more reliable diagnostic tool for detection of CNS leukemia at an early stage than is cytomorphology. At initial diagnosis, the finding of Tdt+ cells in a RBC-free CSF sample with a negative cytomorphology is highly predictive for development of overt CNS leukemia. 相似文献