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   678篇
  免费   68篇
  国内免费   1篇
耳鼻咽喉   5篇
儿科学   11篇
妇产科学   29篇
基础医学   63篇
口腔科学   7篇
临床医学   152篇
内科学   118篇
皮肤病学   6篇
神经病学   53篇
特种医学   16篇
外科学   48篇
综合类   17篇
预防医学   98篇
药学   75篇
中国医学   3篇
肿瘤学   46篇
  2024年   2篇
  2023年   8篇
  2022年   13篇
  2021年   17篇
  2020年   13篇
  2019年   25篇
  2018年   28篇
  2017年   27篇
  2016年   25篇
  2015年   24篇
  2014年   19篇
  2013年   39篇
  2012年   48篇
  2011年   41篇
  2010年   26篇
  2009年   30篇
  2008年   37篇
  2007年   50篇
  2006年   33篇
  2005年   44篇
  2004年   39篇
  2003年   37篇
  2002年   27篇
  2001年   18篇
  2000年   11篇
  1999年   16篇
  1998年   6篇
  1997年   7篇
  1996年   6篇
  1995年   2篇
  1989年   2篇
  1988年   1篇
  1987年   2篇
  1986年   1篇
  1982年   1篇
  1981年   2篇
  1980年   1篇
  1979年   1篇
  1978年   2篇
  1975年   1篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
  1965年   1篇
  1918年   1篇
  1910年   1篇
排序方式: 共有747条查询结果,搜索用时 15 毫秒
1.

Objectives

The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.

Design

Pilot randomised-controlled trial.

Methods

Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.

Results

All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.

Conclusions

This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials.  相似文献   
2.
The aim of this study was to investigate insurance records for a one-year period to determine the injury frequencies and costs associated with different age groups in netball. The insurance records for all netball claims made during 1999 in Victoria were obtained from the insurer and entered into a database. The overall injury rate was 9.49 injuries per 1000 players, with 829 claims for injuries filed with the insurance company. Of all injuries claimed for, 85.3% were to the lower limb, 8.7% to the upper limb, 3.1% to the spine/torso and 2.9% to the head and face. Lower limb injuries accounted for 85.4% of costs, upper limb injuries 10.7% and head/neck/torso injuries 3.9% of total injury costs. Knee injuries accounted for 56.9% of total costs, with ankle and calf/Achilles injuries costing 12.7 and 11.8% of total costs, respectively. Injury prevention strategies should therefore be directed to three main injuries taking into account costs and incidence. These injuries were: ankle sprains, knee ligament sprains and Achilles tendon strains. Specifically, the prevention program for Achilles injuries should be directed to the >25 years age groups.  相似文献   
3.
Since the outbreak of COVID‐19 pandemic, clinicians have had to use personal protective equipment (PPE) for prolonged periods. This has been associated with detrimental effects, especially in relation to the skin health. The present study describes a comprehensive survey of healthcare workers (HCWs) to describe their experiences using PPE in managing COVID‐19 patients, with a particular focus on adverse skin reactions. A 24‐hour prevalence study and multi‐centre prospective survey were designed to capture the impact of PPE on skin health of hospital staff. Questionnaires incorporated demographics of participants, PPE type, usage time, and removal frequency. Participants reported the nature and location of any corresponding adverse skin reactions. The prevalence study included all staff in intensive care from a single centre, while the prospective study used a convenience sample of staff from three acute care providers in the United Kingdom. A total of 108 staff were recruited into the prevalence study, while 307 HCWs from a variety of professional backgrounds and demographics participated in the prospective study. Various skin adverse reactions were reported for the prevalence study, with the bridge of the nose (69%) and ears (30%) being the most affected. Of the six adverse skin reactions recorded for the prospective study, the most common were redness blanching (33%), itchiness (22%), and pressure damage (12%). These occurred predominantly at the bridge of the nose and the ears. There were significant associations (P < .05) between the adverse skin reactions with both the average daily time of PPE usage and the frequency of PPE relief. The comprehensive study revealed that the use of PPE leads to an array of skin reactions at various facial locations of HCWs. Improvements in guidelines are required for PPE usage to protect skin health. In addition, modifications to PPE designs are required to accommodate a range of face shapes and appropriate materials to improve device safety.  相似文献   
4.
5.
  1. Cyclic AMP generation by adenosine analogues was examined in human embryonic kidney (HEK 293) cells by use of a [3H]-adenine pre-labelling methodology.
  2. Adenosine analogues showed the following rank order of potency (pD2 value): 5′-N-ethylcarboxamidoadenosine (NECA, 5.24)>2-chloroadenosine (4.41) ⩾ adenosine (4.19)=N6-(2-(4-aminophenyl)-ethylamino)adenosine (APNEA, 4.11). The A2A-selective agonist CGS21680 failed to elicit a significant stimulation of cyclic AMP generation at concentrations below 30 μM.
  3. Of these agents, NECA was observed to exhibit the greatest intrinsic activity, while in comparison maximal responses to adenosine (76±8% NECA response), 2-chloroadenosine (70±6%) and APNEA (40±3%) were significantly reduced.
  4. Antagonists of the NECA-evoked cyclic AMP generation showed the rank order of apparent affinity (apparent pA2 value): CGS 15943 (7.79)=XAC (7.74)>DPCPX (7.01)=PD115199 (6.93)=8FB-PTP (6.80)>KF 17837 (5.98)>3-propylxanthine (5.13).
  5. Agarose gel electrophoresis of the products of the polymerase chain reaction, with cDNA generated from HEK 293 cell total RNA showed virtually identical patterns and nucleotide sizes in comparison with the vector for the full length human brain A2B adenosine receptor.
  6. We concluded that HEK 293 cells express an endogenous adenosine receptor coupled to cyclic AMP generation which is of the A2B subtype.
  相似文献   
6.
A treatment portal or simulator image has traditionally been used to demonstrate the lung and heart coverage of the breast tangential portal. In many cases, these images were acquired as a planning session on the linear accelerator. The patients were also CT scanned to assess the lung/heart volume and to determine the surgical site depth for the electron‐boost energy. A study using 50 consecutive patients was performed comparing the digitally reconstructed radiograph (DRR) from the virtual simulation with treatment portal images. Modification to the patient's arm position is required when performing the planning CT scans due to the aperture size of the CT scanner. Virtual simulation was used to assess the potential variation of lung and heart measurements. The average difference in lung volume between the DRR and portal image was less than 2 mm, with a range of 0?5 mm. Arm position did not have a sig­nificant impact on field deviation; however, great care was taken to minimize any changes in arm position. The modification of the arm position for CT scanning did not lead to significant variations between the DRRs and portal images. The Advantage Sim software has proven capable of producing good quality DRR images, providing a realistic representation of the lung and heart volume included in the treatment portal.  相似文献   
7.
The aim of this study was to evaluate the improvement in patient comfort and field positional accuracy provided by a new pelvic stabilization system when delivering multiple field radiotherapy to the pelvis. The Pelvic Cradle (BEHTS Manufacturing, Brisbane, Qld, Australia) is a stabilization device that provides reproducible patient positioning and levelling. Ninety patients were randomized into three groups. The first group was treated using the Pelvic Cradle, the second group was treated using current stabilization practices, and the third group was treated using the Pron Pillo (Chattanooga Pharmacal Company, USA) and current stabilization practices. Port films were assessed for field displacement in the lateral and cranio-caudal directions. A patient survey was used to evaluate the patient's perception of comfort while receiving treatment. When compared to the control group, the pelvic cradle group demonstrated a 48% improvement in the mean lateral deviation from 3.8 mm to 2.0 mm (P < 0.001) and a 36% improvement in the mean cranio-caudal deviation from3.9 mm to 2.5 mm (P < 0.001). The Pelvic Cradle was found to provide an improved level of field positional accuracy while maintaining patient comfort.  相似文献   
8.
The experience of cocaine and 'crack' use among participants involved in (n = 19) or exiting (n = 10) prostitution in Glasgow, Scotland, is described. In-depth semi-structured qualitative interviews enquired about their use and experience of using cocaine and their perception of its effect on working practice. Twenty-three of 29 participants had used cocaine and 15 out of 29 had used crack cocaine. In reality, freebase not 'crack' was being self-manufactured from cocaine powder. Participants considered that cocaine use in the city was not restricted to prostitution but was reflected throughout the drug scene generally. One possible reason suggested for this was a perceived reduction in heroin availability at a time when cocaine was increasingly readily available. There was no evidence from participants to suggest that they were first introduced to cocaine through prostitution. Most participants believed that using cocaine did not affect how they worked, however they perceived that other prostitutes were prepared to take more risks to support their cocaine use and had to work longer hours to finance a cocaine habit compared to financing a heroin habit. Only participants recruited from the east end of the city spoke about their desperation for money and the sexual risks that they were prepared to take to buy cocaine. Harm-reduction messages should address the sexual and personal risks that some female prostitutes may be taking to support their cocaine use. Treatment and support services in the city, traditionally established to work with problematic heroin users, need to adapt to the changing drug trends among female drug users, including those involved in prostitution, and offer appropriate treatment options and harm-reduction advice to cocaine users.  相似文献   
9.
10.
Consumer‐directed care is increasingly becoming a mainstream option in community‐based aged care. However, a systematic review describing how the current evaluation research translates into practise has not been published to date. This review aimed to systematically establish an evidence base of user preferences for and satisfaction with services associated with consumer‐directed care programmes for older people. Twelve databases were searched, including MedLine, BioMed Central, Cinahl, Expanded Academic ASAP, PsychInfo, ProQuest, Age Line, Science Direct, Social Citation Index, Sociological Abstracts, Web of Science and the Cochrane Library. Google Scholar and Google were also searched. Eligible studies were those reporting on choice, user preferences and service satisfaction outcomes regarding a programme or model of home‐based care in the United States or United Kingdom. This systematic narrative review retrieved literature published from January 1992 to August 2011. A total of 277 references were identified. Of these 17 met the selection criteria and were reviewed. Findings indicate that older people report varying preferences for consumer‐directed care with some demonstrating limited interest. Clients and carers reported good service satisfaction. However, research comparing user preferences across countries or investigating how ecological factors shape user preferences has received limited attention. Policy‐makers and practitioners need to carefully consider the diverse contexts, needs and preferences of older adults in adopting consumer‐directed care approaches in community aged care. The review calls for the development of consumer‐directed care programmes offering a broad range of options that allow for personalisation and greater control over services without necessarily transferring the responsibility for administrative responsibilities to service users. Review findings suggest that consumer‐directed care approaches have the potential to empower older people.  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