全文获取类型
收费全文 | 622篇 |
免费 | 67篇 |
国内免费 | 22篇 |
专业分类
儿科学 | 34篇 |
妇产科学 | 12篇 |
基础医学 | 79篇 |
口腔科学 | 7篇 |
临床医学 | 77篇 |
内科学 | 172篇 |
皮肤病学 | 5篇 |
神经病学 | 99篇 |
特种医学 | 79篇 |
外科学 | 47篇 |
综合类 | 14篇 |
预防医学 | 34篇 |
眼科学 | 1篇 |
药学 | 28篇 |
肿瘤学 | 23篇 |
出版年
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 11篇 |
2018年 | 20篇 |
2016年 | 10篇 |
2015年 | 9篇 |
2014年 | 18篇 |
2013年 | 23篇 |
2012年 | 26篇 |
2011年 | 22篇 |
2010年 | 20篇 |
2009年 | 16篇 |
2008年 | 20篇 |
2007年 | 41篇 |
2006年 | 23篇 |
2005年 | 12篇 |
2004年 | 16篇 |
2003年 | 23篇 |
2002年 | 19篇 |
2001年 | 19篇 |
2000年 | 14篇 |
1999年 | 22篇 |
1998年 | 17篇 |
1997年 | 24篇 |
1996年 | 22篇 |
1995年 | 17篇 |
1994年 | 9篇 |
1993年 | 12篇 |
1992年 | 10篇 |
1991年 | 5篇 |
1990年 | 10篇 |
1989年 | 20篇 |
1988年 | 18篇 |
1987年 | 12篇 |
1986年 | 24篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1980年 | 4篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1969年 | 6篇 |
1967年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有711条查询结果,搜索用时 15 毫秒
71.
Platelet membrane glycoprotein changes during the preparation and storage of platelet concentrates 总被引:6,自引:0,他引:6
Previous studies of platelet membrane glycoproteins during blood bank storage have reported conflicting results. This study assessed two major plasma membrane glycoproteins (GP Ib and GP IIb), an alpha-granule membrane protein (GMP-140), and the concentration of platelet membrane microparticles in cell-free plasma during routine hospital blood bank platelet storage. 125I-monoclonal antibody binding was used to measure membrane glycoproteins on the surface of intact platelets and to measure the concentration of membrane microparticles in cell-free plasma. Platelet concentrates were stored at room temperature in polyolefin bags for 7 days. In this blood bank, two types of rotators are routinely used for platelet concentrate storage: a 2-rpm circular tumbler rotator and a 6-rpm elliptical rotator. Different results were obtained with the rotators. With the tumbler rotator, there was no loss of platelets and antibody binding to GP Ib remained normal. With the elliptical rotator, one third of platelets were lost into clumps during storage, and a 50 percent decrease of antibody binding to GP Ib occurred in the remaining single platelets. There was no loss of antibody binding to GP IIb with either rotator. Antibody binding to GMP-140 increased equally in both rotators indicating that the remaining single platelets had secreted about 16 percent of their alpha-granule contents. The plasma concentration of platelet membrane microparticles was greater in the bags stored in the elliptical rotator. These results indicate that it is possible to maintain the normal concentration of platelet membrane glycoproteins Ib and IIb during 7 days of room-temperature blood bank storage.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
72.
B Detournay M Pechevis M Mane B Bussel JN Bail JB Tiebaut 《Annales de Réadaptation et de Médecine Physique》1998,41(8):491-497
A medicoeconomic evaluation of continuous intrathecal baclofen (Lioresal®) infusion for symptomatic treatment of severe spinal spasticity was realised using a monocentric, comparative, retrospective approach where subjects were their own controls (n = 22). Study results confirm the efficacy of baclofen on symptoms, functional status of patients and on a non specific quality of life scale. Conversely, use of baclofen lead to a 67% increase of average annual costs of care for these patients and reaches around 173,500 French francs (~29,000 US$)/year. Such a cost seems to be acceptable with respect to clinical benefits. © 1998 Elsevier, Paris 相似文献
73.
目的:了解延边地区朝鲜族和汉族居民的脂肪分布特征及其与血压、血脂及血糖的关系。方法:于2006-08-8/17在延边地区九龙和翁声社区随机选择40~60岁朝鲜族和汉族常住居民2378名进行内脏脂肪率和体脂肪率以及血压、血脂、血糖等生化指标的检测。调查以健康体检形式进行,①内脏脂肪和体脂肪率测定采用日本TANITA株式会社生产的BC-600型体成分计测定,并且按其判定标准确定超过标准者[内脏脂肪率≥15%(男)、≥10%(女),体脂肪率(40~59岁)≥23%(男)、≥36%(女),体脂肪率(≥60岁)≥25%(男)、≥37%(女)]。②取清晨空腹(禁食12h)静脉血,采用日立-7600-010全自动生化分析仪测量血清总胆固醇、三酰甘油、高密度脂蛋白胆固醇、空腹血糖等指标。③高血压的诊断标准:收缩压≥140mmHg(1mmHg=0.133kPa)及或舒张压≥90mmHg。④血脂异常的诊断标准:总胆固醇≥5.72mmol/L,三酰甘油≥1.7mmol/L,高密度脂蛋白胆固醇<0.90mmol/L(男)、<1.0mmol/L(女)。⑤高血糖的诊断标准:空腹血糖≥6.1mmol/L。结果:①汉族男性的内脏脂肪率和体脂肪率均值分别为(10.51±3.66)%和(22.70±4.85)%,朝鲜族男性分别为(9.16±3.81)%和(20.28±5.02)%,汉族均高于朝鲜族(P<0.01);汉族女性的内脏脂肪率和体脂肪率分别为(6.22±2.27)%和(35.31±5.65)%,朝鲜族女性分别为(5.88±2.19)%和(34.00±5.72)%,汉族均高于朝鲜族(P<0.01)。②汉族男性的内脏脂肪率和体脂肪率超标率分别为12.1%和45.8%,朝鲜族男性分别为7.8%和28.6%,汉族均高于朝鲜族(P<0.05);汉族女性的内脏脂肪率和体脂肪率超标率分别为6.7%和47.9%,朝鲜族女性分别为3.8%和37.3%,汉族均高于朝鲜族(P<0.05)。③Logistic逐步回归分析结果表明,内脏脂肪率与民族、性别、年龄、高血压、高三酰甘油血症和高血糖有密切关系;体脂肪率与民族、性别、高血压、高三酰甘油血症、低高密度脂蛋白血症和高血糖有密切的关系。结论:①延边地区汉族居民内脏脂肪率和体脂肪率平均水平及其超标率明显高于朝鲜族。②内脏脂肪率和体脂肪率均与民族、性别、年龄(体脂肪率除外)、高血压、高三酰甘油血症和高血糖相关。 相似文献
74.
75.
Brennan Spiegel Roger Bolus Amar A. Desai Philip Zagar Tom Parker John Moran Matthew D. Solomon Osman Khawar Matthew Gitlin Jennifer Talley Allen Nissenson 《Clinical journal of the American Society of Nephrology》2010,5(11):2024-2033
Background and objectives: Mortality rates vary widely among dialysis facilities even after adjustment with standardized mortality ratios (SMRs). This variation may occur because top-performing facilities use practices not shared by others, because the SMR fails to capture key patient characteristics, or both. Practices were identified that distinguish top- from bottom-performing facilities by SMR.Design, setting, participants, & measurements: A cross-sectional survey was performed of staff across three organizations. Staff members rated the perceived quality of their units'' patient-, provider-, and facility-level practices using a six-point Likert scale. Facilities were divided into those with above- versus below-expected mortality on the basis of SMRs from U.S. Renal Data Service facility reports. Mean Likert scores were computed for each practice using t tests. Practices that were statistically significant (P ≤ 0.05) and achieved at least a medium effect size of ≥0.4 were reported. Significant predictors were entered into a linear regression model.Results: Dialysis facilities with below-expected mortality reported that patients in their unit were more activated and engaged, physician communication and interpersonal relationships were stronger, dieticians were more resourceful and knowledgeable, and overall coordination and staff management were superior versus facilities with above-expected mortality. Staff ratings of these practices explained 31% of the variance in SMRs.Conclusions: Patient-, provider-, and facility-level practices partly explain SMR variation among facilities. Improving SMRs may require processes that reflect a coordinated, multidisciplinary environment (i.e., no one group, practice, or characteristic will drive facility-level SMRs). Understanding and improving SMRs will require a holistic view of the facility.Since 1995, the U.S. Renal Data System (USRDS) has calculated standardized mortality ratios (SMRs) to estimate patient survival in dialysis facilities. Because unadjusted mortality rates cannot capture the inevitable case-mix variations among facilities, the SMR is adjusted for a range of variables including age, sex, race, disease duration, comorbidities, nursing home status, and body mass index (1,2). SMR further adjusts for underlying mortality rates by scaling observed mortality by expected mortality on the basis of national data. Individual facilities are classified as having lower (SMR < 1.0), higher (SMR > 1.0), or as-expected (SMR = 1.0) mortality compared with the national average (1,2). This information is publicly available (3) and allows payers and consumers to monitor quality within individual facilities and to compare quality among facilities.Despite attempts to adjust for case-mix variations, patient survival varies among dialysis facilities even after adjustment. McClellan and colleagues evaluated mortality rates in a cohort of dialysis units and showed that facility-specific mortality ranged between 2.0 and 10.5 deaths per 10,000 patient days; variations remained after extensive adjustment (4). Goodkin and colleagues found that intra- and international mortality variations also remained after adjusting for a range of demographic characteristics and comorbidities (5). In short, mortality varies from center to center, and this variation is not explained by case-mix adjustment alone.If case-mix adjustment is inadequate to fully explain mortality variations, then what else might explain the differences? One possibility is that there may be important differences in facility-level factors that affect SMRs. These factors may include procedural (e.g., implementation patterns of policies in a facility), attitudinal (e.g., staff morale), interpersonal (e.g., staff communication), or structural (e.g., layout of facilities) practices associated with reduced SMRs (6). There may also be additional patient-level characteristics that are unaccounted for with standard case-mix adjustment. These factors may be incremental to standard demographics and comorbidities or may even supersede those factors. For example, it is possible that top-performing units have more compliant, more motivated, or more disciplined patients compared with bottom-performing units—all characteristics that elude standardized adjustments.To test the hypothesis that there are patient-, provider-, and facility-level factors that are associated with SMRs, and to further elucidate predictors of SMRs, we conducted the Identifying Best Practices in Dialysis (IBPiD) study; this study aims to catalogue best practices associated with improved patient outcomes in dialysis, including SMRs (6). In this study, we identify predictors of mortality that are not traditionally included in case-mix adjustments. 相似文献
76.
77.
78.
Gitlin LN Hauck WW Dennis MP Schulz R 《Journal of the American Geriatrics Society》2007,55(7):1023-1030
OBJECTIVES: To examine whether control-oriented strategies buffer effects of functional difficulties on depressive symptoms over time in older African-American and white adults with disability. DESIGN: Community-based, prospective study. SETTING: Baseline and 12-month data from a randomized trial. PARTICIPANTS: One hundred twenty-nine African-American and 151 white older adults with 12-month data from 319 participants in the trial. MEASUREMENTS: Data were obtained for functional difficulties, the extent that respondents reported using control (cognitive and behavioral) strategies to enhance and maintain independence, and baseline and 12-month depressive symptoms (Center for Epidemiologic Studies Depression Scale; CES-D). RESULTS: African Americans reported greater baseline functional difficulty (P=.009), fewer depressive symptoms (P=.002) and higher control strategy use (P=.001) than whites. Functional difficulty was associated with depressive symptoms for both groups at baseline and 12 months. Living alone for whites and low spirituality for African Americans predicted higher 12-month depressive symptom scores. African Americans with baseline functional difficulty and high strategy use had lower 12-month depression than those with similar difficulty levels but low strategy use (P=.04 for interaction), representing a 28.5-point CES-D score differential. Control strategies did not buffer the function-depression relationship over time for whites. CONCLUSION: Control-oriented strategies moderated the experience of depressive symptomatology over time for African Americans with disability but not for whites. This may explain the paradox of greater functional disparities but less reported emotional distress in African Americans than whites. Results suggest that the use and benefits of adaptive resources to attain functional goals and determinants of depression differ by race. Depression prevention programs should be modified to be suitable for different cultural groups. 相似文献
79.
80.