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   728篇
  免费   10篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   21篇
妇产科学   2篇
基础医学   61篇
口腔科学   3篇
临床医学   102篇
内科学   81篇
皮肤病学   4篇
神经病学   138篇
特种医学   12篇
外科学   38篇
综合类   89篇
预防医学   68篇
眼科学   2篇
药学   82篇
中国医学   28篇
肿瘤学   8篇
  2024年   2篇
  2023年   8篇
  2022年   13篇
  2021年   8篇
  2020年   6篇
  2019年   64篇
  2018年   45篇
  2017年   17篇
  2016年   16篇
  2015年   12篇
  2014年   54篇
  2013年   37篇
  2012年   52篇
  2011年   60篇
  2010年   45篇
  2009年   48篇
  2008年   25篇
  2007年   44篇
  2006年   27篇
  2005年   25篇
  2004年   18篇
  2003年   19篇
  2002年   12篇
  2001年   6篇
  2000年   5篇
  1999年   8篇
  1998年   3篇
  1997年   4篇
  1996年   3篇
  1995年   5篇
  1994年   2篇
  1993年   2篇
  1991年   2篇
  1990年   2篇
  1986年   2篇
  1985年   3篇
  1984年   3篇
  1983年   5篇
  1982年   4篇
  1980年   4篇
  1979年   6篇
  1978年   4篇
  1977年   1篇
  1976年   1篇
  1975年   2篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
  1968年   2篇
排序方式: 共有741条查询结果,搜索用时 15 毫秒
71.
目前检测血浆凝血酶原时间(PT)、部分凝血活酶时间(APTT)、凝血酶时间(TT)、凝血因子(Fib)所采用的质控物为进口冻干质控物,但由于其价格昂贵,许多基层实验室难以承受,因而影响了基层医院室内质控持续有效地开展。从实用出发,经过不断探索和比较分析,最终研究配制出了配方合理、成本低廉、效果好、结果稳定的液体凝血止血检验质控物。该质控物经过一年的室内质控应用及参加云南省临床检验中心凝血-止血功能项目室间质控活动,取得优秀成绩。说明该质控物质量均达到与进口冻干质控物同样的水平,完全可以替代进口冻干质控物,可应用于各级医院凝血—止血功能试验的实验室检测,达到提高检验质量的目的,并发挥良好的社会效益和经济效益。  相似文献   
72.
Summary. Background: The WHO scheme for prothrombin time (PT) standardization has been limited in application, because of its difficulties in implementation, particularly the need for mandatory manual PT testing and for local provision of thromboplastin international reference preparations (IRP). Methods: The value of a new simpler procedure to derive international normalized ratio (INR), the PT/INR Line, based on only five European Concerted Action on Anticoagulation (ECAA) calibrant plasmas certified by experienced centres has been assessed in two independent exercises using a range of commercial thromboplastins and coagulometers. INRs were compared with manual certified values with thromboplastin IRP from expert centres and in the second study also with INRs from local ISI calibrations. Results: In the first study with the PT/INR Line, 8.7% deviation from certified INRs was reduced to 1.1% with human reagents, and from 7.0% to 2.6% with rabbit reagents. In the second study, deviation was reduced from 11.2% to 0.4% with human reagents by both local ISI calibration and the PT/INR Line. With rabbit reagents, 10.4% deviation was reduced to 1.1% with both procedures; 4.9% deviation was reduced to 0.5% with bovine/combined reagents with local ISI calibrations and to 2.9% with the PT/INR Line. Mean INR dispersion was reduced with all thromboplastins and automated systems using the PT/INR Line. Conclusions: The procedure using the PT/INR Line provides reliable INR derivation without the need for WHO ISI calibration across the range of locally used commercial thromboplastins and automated PT systems included in two independent international studies.  相似文献   
73.
不同型号仪器测定凝血酶原时间的可比性研究   总被引:2,自引:0,他引:2  
目的探讨不同型号血凝仪检测凝血酶原时间(PT)的检测结果是否具有可比性。方法分别采用不同水平STAGO质控物、DADE质控物和75例不同浓度的患者新鲜血浆,在2个不同的检测系统(STA—R、CA7000)测定PT,并对其检测结果进行相关的统计学分析。结果5个水平的质控物测定结果经t检验,各组间的差异均有显著性(P〈0.01)。各检测系统间不同浓度的患者新鲜血浆测定结果差异有非常显著性(P〈0.01);相关系数均=0.975。以STA—R作标准检测系统对其他检测系统作临床可接受性能评价,CA7000可接受。结论2个检测系统测定PT精密度和临床可接受性能评价均符合临床要求,应定期对以上的检测系统进行比对实验,以保证检验结果间的可比性。  相似文献   
74.

Objective

To perform a cost-effectiveness analysis of a multifactorial, tailored intervention to reduce falls among a heterogeneous group of high-risk elderly people.

Design

Randomized control trial.

Settings

Communities.

Participants

Adults aged at least 65 years (N=354) seen at the emergency department (ED) for a fall or fall-related injury and discharged home.

Interventions

The intervention group received a tailored program of physical therapy focused on progressive training in strength, balance, and gait for a period of 3 months. They also received screening and referrals for low vision, polypharmacy, and environmental hazards. The Short Physical Performance Battery (SPPB) test was assessed at regular intervals to allocate participants into either a home-based or group center-based program. The control group received usual care prescribed by a physician and educational materials on falls prevention.

Main Outcome Measures

The incremental cost-effectiveness ratio (ICER) over the 9-month study period based on intervention costs and utility in terms of quality-adjusted life years (QALYs) calculated from EuroQol-5D scores.

Results

The ICER was 120,667 Singapore dollars (S$) per QALY gained (S$362/0.003 QALYs), above benchmark values (S$70,000). However, the intervention was more effective and cost-saving among those with SPPB scores of greater than 6 at baseline, higher cognitive function, better vision and no more than 1 fall in the preceding 6 months. The intervention was also cost-effective among those with 0-1 critical comorbidities (S$22,646/QALY).

Conclusion

The intervention was, overall, not cost-effective, compared to usual care. However, the program was cost-effective among healthier subgroups, and even potentially cost-saving among individuals with sufficient reserve to benefit.  相似文献   
75.

Objective

Determine agreement between self-reported dose and dose reflected in administrative records of outpatient physical, occupational, and speech therapies at 6 and 12 months after severe traumatic brain injury (TBI), for the purpose of examining accuracy and predictors of accuracy of self-reported health care utilization in this population.

Design

Secondary analysis of survey used in a larger study; participants were queried about therapy doses using a structured interview, either alone or assisted by relatives if they so chose, with responses compared to administrative records.

Setting

Rehabilitation center providing outpatient TBI therapies.

Participants

Sixty-five people with severe TBI living in the community provided 6-month data (N=65); 54 provided 12-month data.

Interventions

Not applicable.

Main Outcome Measures

Degree of agreement with administrative records of scheduled and billed therapy appointments, measured using intraclass correlation coefficients (ICCs), with linear regression used to predict accuracy from demographic variables and cognitive status.

Results

ICCs were in the moderate range at 6 months, but were more variable, with some in the poor range, at 12 months. Agreement was higher for scheduled than for billed (attended) appointments. Assisted and unassisted patients provided comparable agreement with records. No demographic factors were associated with accuracy, but lower cognitive FIM scores, as hypothesized, tended to predict lower agreement at 6 months.

Conclusions

People with severe TBI can provide reasonable estimates of commonly prescribed outpatient therapy doses at 6 months postinjury. Accuracy may be improved by inviting patients to request assistance from relatives and by asking them to consider attended (vs scheduled) sessions.  相似文献   
76.

Objective

To examine the effectiveness of epidural steroid injection (ESI) and back education with and without physical therapy (PT) in individuals with lumbar spinal stenosis (LSS).

Design

Randomized clinical trial.

Setting

Orthopedic spine clinics.

Participants

A total of 390 individuals were screened with 60 eligible and randomly selected to receive ESI and education with or without PT (N=54).

Interventions

A total of 54 individuals received 1-3 injections and education in a 10-week intervention period, with 31 receiving injections and education only (ESI) and 23 additionally receiving 8-10 sessions of multimodal PT (ESI+PT).

Main Outcome Measures

Disability, pain, quality of life, and global rating of change were collected at 10 weeks, 6 months, and 1 year and analyzed using linear mixed model analysis.

Results

No significant difference was found between ESI and ESI+PT in the Oswestry Disability Index at any time point, although the sample had significant improvements at 10 weeks (P<.001; 95% confidence interval [CI], ?18.01 to ?5.51) and 1 year (P=.01; 95% CI, ?14.57 to ?2.03) above minimal clinically important difference. Significant differences in the RAND 36-Item Short Form Health Survey 1.0 were found for ESI+PT at 10 weeks with higher emotional role function (P=.03; 95% CI, ?49.05 to ?8.01), emotional well-being (P=.02; 95% CI, ?19.52 to -2.99), and general health perception (P=.05; 95% CI, ?17.20 to ?.78).

Conclusions

Epidural steroid injection plus PT was not superior to ESI alone for reducing disability in individuals with LSS. Significant benefit was found for the addition of PT related to quality of life factors of emotional function, emotional well-being, and perception of general health.  相似文献   
77.

Introduction

Coagulation abnormalities are frequent in patients with severe infections. However, the predictive value of d-dimer and of the presence of associated coagulation derangements in severe community-acquired pneumonia (CAP) remains to be thoroughly evaluated. The aim of this study was to investigate the predictive value of coagulation parameters in patients with severe CAP admitted to the intensive care unit.

Methods

d-Dimer, antithrombin, International Society of Thrombosis and Hemostasis score, clinical variables, Sequential Organ Failure Assessment (SOFA), The Acute Physiology and Chronic Health Evaluation II (APACHE II) and the CURB-65 score were measured in the first 24 hours. Results are shown as median (25%-75% interquartile range). The main outcome measure was hospital mortality.

Results

Ninety patients with severe CAP admitted to the intensive care unit were evaluated. Overall hospital mortality was 15.5%. d-Dimer levels in nonsurvivors were higher than those in survivors. In the univariate analysis, d-dimer, SOFA, and APACHE II scores were predictors of death. The discriminative ability of d-dimer (area under receiver operating curve = 0.75 [95% confidence interval, 0.64-0.83]; best cutoff for d-dimer was 1798 ng/mL) for in-hospital mortality was comparable with APACHE II and SOFA and better than C-reactive protein. Moreover, the addition of d-dimer to APACHE II or SOFA score increased the discriminative ability of both scores (area under the receiver operating curve = 0.82 [0.72-0.89] and 0.84 [0.75-0.91], respectively).

Conclusions

d-Dimer levels are good predictors of outcome in severe CAP and may augment the predictive ability of scoring systems as APACHE II and SOFA.  相似文献   
78.

Objective

To compare the efficacy of intra-articular (IA) steroid injection and distension in patients with frozen shoulder.

Data Sources

Databases, including MEDLINE (via PubMed), Embase, Scopus, and Cochrane Library, were searched for studies published up to November 2016.

Study Selection

We included all published randomized controlled trials (RCTs), quasi-experimental studies, and observational studies investigating the effectiveness of IA steroid injection, distension, and physiotherapy in patients with frozen shoulder. Sixteen RCTs and 1 observational study were enrolled in meta-analysis.

Data Extraction

Full texts were independently reviewed, and quality of RCTs was assessed with The Cochrane Collaboration's tool. The primary outcome was functional improvement; the secondary outcomes included pain reduction and external rotation (ER) improvement.

Data Synthesis

In pairwise meta-analysis, pooled standardized mean difference (SMD) of functional improvement and pain reduction revealed equal efficacy at 3 follow-up time points. With respect to ER improvement, distension has a superior effect compared with IA steroid injection in the short term [(2–4wk; SMD, ?.36; 95% confidence interval [CI], ?.68 to ?.04) and medium term (6–16wk; SMD, ?0.80; 95% CI, ?1.32 to ?0.29). The network meta-analysis indicated a better efficacy for distension than for IA steroid injection in ER improvement only in the medium term (6–16wk; SMD, ?0.70; 95% CI, ?1.19 to ?0.21).

Conclusions

IA steroid injection was as effective as distension in shoulder function improvement, pain reduction, and increasing ER of the shoulder. Distension yielded better ER improvement in the medium term but to a minor extent in the long term. For patients with predominant ER limitation, early distension could be considered the primary choice of treatment.  相似文献   
79.
We have recently shown that vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) exhibit enhanced expression of Giα proteins, which was attributed to the enhanced oxidative stress. Since C-ANP4-23 that specifically interacts with natriuretic peptide C (NPR-C) receptor has been shown to decrease the expression of Giα protein in VSMC, the present study was undertaken to examine if C-ANP4-23 can also decrease the enhanced expression of Giα protein in VSMC from SHR and whether it is attributed to its ability to attenuate the enhanced oxidative stress. Aortic VSMC from 12-week-old SHR and their age-matched Wistar-Kyoto (WKY) rats were used for the present studies. VSMC from SHR exhibited enhanced expression of Giα-2 and Giα-3 proteins, different subunits of NADPH oxidase such as Nox4 and p47phox proteins but not of p22phox, enhanced production of superoxide anion as well as NADPH oxidase activity as compared to age-matched WKY rats. Treatment of VSMC from SHR with C-ANP4-23 decreased towards control levels the enhanced expression of Giα proteins, enhanced superoxide anion production and enhanced NADPH oxidase activity as well as the enhanced expression of Nox4 and p47phox. However, C-ANP4-23-induced attenuation of the enhanced level of O2 and NADPH oxidase activity occurs at 4 h before the decrease in the enhanced expression of p47phox that occurs at 16 h of C-ANP4-23 treatment. The decreased expression of NADPH oxidase in SHR was also associated with further decrease in O2 and NADPH oxidase activity. Furthermore, treatment of VSMC from SHR with pertussis toxin (PT) decreased the enhanced levels of superoxide anion as well as NADPH oxidase activity; however, the enhanced levels of different subunits of NADPH oxidase were not attenuated by PT treatment. These results suggest that C-ANP4-23 decreases the enhanced oxidative stress in SHR by attenuating the enhanced expression of Giα proteins and also the enhanced levels of NADPH oxidase.  相似文献   
80.

Background

Evidence suggests CaHMB may impact muscle mass and/or strength in older adults, yet no long-term studies have compared its effectiveness in sedentary and resistance training conditions. The purpose of this study was to evaluate the effects of 24 weeks of CaHMB supplementation and resistance training (3 d wk− 1) or CaHMB supplementation only in ≥ 65 yr old adults.

Methods

This double-blinded, placebo-controlled, trial occurred in two phases under ad libitum conditions. Phase I consisted of two non-exercise groups: (a) placebo and (b) 3 g CaHMB consumed twice daily. Phase II consisted of two resistance exercise groups: (a) placebo and resistance exercise and (b) 3 g CaHMB consumed twice daily and resistance exercise (RE). Strength and functionality were assessed in both phases with isokinetic leg extension and flexion at 60°·s− 1 and 180°·s− 1 (LE60, LF60, LE180, LF180), hand grip strength (HG) and get-up-and-go (GUG). Dual X-Ray Absorptiometry (DXA) was used to measure arm, leg, and total body lean mass (LM) as well as total fat mass (FM). Muscle Quality was measured for arm (MQHG = HG/arm LM) and Leg (MQ60 = LE60/leg LM) (MQ180 = LE180/leg LM).

Results

At 24 weeks of Phase I, change in LE60 (+ 8.8%) and MQ180 (+ 20.8%) for CaHMB was significantly (p < 0.05) greater than that for placebo group. Additionally, only CaHMB showed significant (p < 0.05) improvements in total LM (2.2%), leg LM (2.1%), and LE180 (+ 17.3%), though no treatment effect was observed. Phase II demonstrated that RE significantly improved total LM (4.3%), LE60 (22.8%), LE180 (21.4%), HG (9.8%), and GUG (10.2%) with no difference between treatment groups. At week 24, only CaHMB group significantly improved FM (− 3.8%) and MQHG (7.3%); however there was no treatment main effect for these variables.

Conclusion

CaHMB improved strength and MQ without RE. Further, RE is an effective intervention for improving all measures of body composition and functionality.  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