全文获取类型
收费全文 | 526篇 |
免费 | 35篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 19篇 |
妇产科学 | 1篇 |
基础医学 | 59篇 |
口腔科学 | 6篇 |
临床医学 | 46篇 |
内科学 | 69篇 |
皮肤病学 | 3篇 |
神经病学 | 47篇 |
特种医学 | 37篇 |
外科学 | 82篇 |
综合类 | 12篇 |
预防医学 | 36篇 |
眼科学 | 8篇 |
药学 | 78篇 |
中国医学 | 1篇 |
肿瘤学 | 56篇 |
出版年
2022年 | 3篇 |
2021年 | 5篇 |
2019年 | 7篇 |
2018年 | 7篇 |
2017年 | 3篇 |
2016年 | 13篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 12篇 |
2012年 | 32篇 |
2011年 | 29篇 |
2010年 | 18篇 |
2009年 | 19篇 |
2008年 | 31篇 |
2007年 | 31篇 |
2006年 | 18篇 |
2005年 | 25篇 |
2004年 | 28篇 |
2003年 | 20篇 |
2002年 | 21篇 |
2001年 | 23篇 |
2000年 | 20篇 |
1999年 | 15篇 |
1998年 | 17篇 |
1997年 | 21篇 |
1996年 | 17篇 |
1995年 | 11篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 8篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1972年 | 2篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1940年 | 1篇 |
1931年 | 1篇 |
1907年 | 1篇 |
排序方式: 共有562条查询结果,搜索用时 62 毫秒
21.
Michael Browning Jonathan Kingslake Colin T. Dourish Guy M. Goodwin Catherine J Harmer Gerard R. Dawson 《European neuropsychopharmacology》2019,29(1):66-75
Antidepressants must be taken for weeks before response can be assessed with many patients not responding to the first medication prescribed. This often results in long delays before effective treatment is started. Antidepressants induce changes in the processing of emotional stimuli early in the course of treatment. In the current study we assessed whether changes in emotional processing and subjective symptoms over the first week of antidepressant treatment predicted clinical response after 4–8 weeks of treatment. Such a predictive test may shorten the time taken to initiate effective treatment in depressed patients. Seventy-four depressed primary care patients completed measures of emotional bias and subjective symptoms before starting antidepressant treatment and then again 1 week later. Response to treatment was assessed after 4–6 weeks. The performance of classifiers based on these measures was assessed using a leave-one-out validation procedure with the best classifier then tested in an independent sample from a second study of 239 patients. The combination of a facial emotion recognition task and subjective symptoms predicted response with 77% accuracy in the training sample and 60% accuracy in the independent study, significantly better than possible using baseline response rates. The face based measure of emotional bias provided good quality data with high acceptability ratings. Changes in emotional processing can provide a sensitive early measure of antidepressant efficacy for individual patients. Early treatment induced changes in emotional processing may be used to guide antidepressant therapy and reduce the time taken for depressed patients to return to good mental health. 相似文献
22.
Tina Harmer Lassen Hanne Frederiksen Tina Kold Jensen J?rgen Holm Petersen Ulla N. Joensen Katharina M. Main Niels E. Skakkebaek Anders Juul Niels J?rgensen Anna-Maria Andersson 《Environmental health perspectives》2014,122(5):478-484
Background: Few human studies have examined bisphenol A (BPA) exposure in relation to semen quality and reproductive hormones in men, and results are divergent.Objectives: We examined associations between urinary BPA concentration and reproductive hormones, as well as semen quality, in young men from the general population.Methods: Our study population consisted of 308 young men from the general population. Urinary BPA concentration was measured by isotope dilution TurboFlow-liquid chromatography–tandem mass spectrometry. We used multiple linear regression analysis to estimate associations between BPA concentration and reproductive hormones and semen quality, adjusting for confounding factors.Results: We found that 98% of the men had detectable urinary levels of BPA. Median (5th–95th percentiles) BPA concentration was 3.25 ng/mL (0.59–14.89 ng/mL). Men with BPA concentrations above the lowest quartile had higher concentrations of serum testosterone, luteinizing hormone (LH), estradiol, and free testosterone compared with the lowest quartile (ptrend ≤ 0.02). Men in the highest quartile of BPA excretion had on average 18% higher total testosterone (95% CI: 8, 28%), 22% higher LH (95% CI: 6, 39%), and 13% higher estradiol (95% CI: 4, 24%) compared with lowest quartile. Men in the highest quartile of BPA also had significantly lower percentage progressive motile spermatozoa compared with men in the lowest quartile (–6.7 percentage points, 95% CI: –11.76, –1.63). BPA was not associated with other semen parameters. Adjusting for dietary patterns did not influence the results.Conclusions: The pattern of associations between BPA and reproductive hormones could indicate an antiandrogenic or antiestrogenic effect, or both, of BPA on the hypothalamic–pituitary–gonadal hormone feedback system, possibly through a competitive inhibition at the receptor level. However, additional research is needed to confirm our findings and to further test the suggested potential mechanisms.Citation: Lassen TH, Frederiksen H, Jensen TK, Petersen JH, Joensen UN, Main KM, Skakkebaek NE, Juul A, Jørgensen N, Andersson AM. 2014. Urinary bisphenol A levels in young men: association with reproductive hormones and semen quality. Environ Health Perspect 122:478–484; http://dx.doi.org/10.1289/ehp.1307309 相似文献
23.
Exercise and Fall Prevention: Narrowing the Research‐to‐Practice Gap and Enhancing Integration of Clinical and Community Practice
下载免费PDF全文
![点击此处可从《Journal of the American Geriatrics Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Fuzhong Li PhD Elizabeth Eckstrom MD MPH Peter Harmer PhD MPH Kathleen Fitzgerald MD Jan Voit PT Kathleen A. Cameron MPH 《Journal of the American Geriatrics Society》2016,64(2):425-431
Falls in older adults are a global public health crisis, but mounting evidence from randomized controlled trials shows that falls can be reduced through exercise. Public health authorities and healthcare professionals endorse the use of evidence‐based, exercise‐focused fall interventions, but there are major obstacles to translating and disseminating research findings into healthcare practice, including lack of evidence of the transferability of efficacy trial results to clinical and community settings, insufficient local expertise to roll out community exercise programs, and inadequate infrastructure to integrate evidence‐based programs into clinical and community practice. The practical solutions highlighted in this article can be used to address these evidence‐to‐practice challenges. Falls and their associated healthcare costs can be reduced by better integrating research on exercise intervention into clinical practice and community programs. 相似文献
24.
25.
W. M. Howell A. Harmer D. Briggs P. Dyer S. V. Fuggle S. Martin P. Sinnott J. Smith C. J. Taylor R. Vaughan 《International journal of immunogenetics》2010,37(6):435-437
Ongoing technological developments in antibody detection and characterisation allowing relative quantitation of HLA-specific antibody levels, combined with crossmatch results, now allow a graded assessment of patient potential donor immunological risk for allotransplantation, rather than a simple ‘positive’ or ‘negative’ categorization of crossmatch results. These developments have driven a thorough revision of the British Society for Histocompatibility & Immunogenetics and British Transplantation Society Guidelines for the Detection and Characterisation of Clinically Relevant Antibodies in Allotransplantation. These newly published revised Guidelines contain a number of recommendations as to best practice for antibody detection and crossmatching for the transplantation of a wide range of solid organs and tissues. These recommendations are briefly summarized in this article. 相似文献
26.
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献
27.
28.
Thyroid cancers are a diverse group of malignant disorders ranging from indolent micropapillary carcinoma, which has no effect on life expectancy, to anaplastic tumours, which are invariably fatal even with aggressive treatment. Although the estimated incidence has increased by 14.6% over the past 40 years, the estimated death rate has fallen by 21%, probably as a result of earlier diagnosis. The natural history of thyroid tumours is no longer a mystery, and the prognostic factors identified can predict outcome fairly accurately. Improvements in management have mostly depended on information from large retrospective series, though there are still many areas open to debate. There has been, however, a general acceptance that thyroid cancer should be managed by multidisciplinary teams in specialised units following evidence-based guidelines. 相似文献
29.
Flow cytometric screening of sera using pooled chronic lymphocytic leukaemia (CLL) cells has previously been reported as a quick method for detecting HLA antibodies of the IgG class. In this study we investigated the sensitivity of this method in the detection of IgG and IgM alloantibodies, and its performance in serum screening when compared to conventional microlymphocytotoxic screening. Results indicate that flow cytometric screening is more sensitive in the measurement of IgG alloantibodies by up to five doubling dilutions, whereas the converse is true for IgM. IgM autoantibodies were found not to be detectable by flow cytometry. By testing a large number of sera by both methods in parallel, we have found that a significant proportion of sera exhibiting no activity or IgM activity alone on cytotoxic screening contain IgG antibodies detectable with a pool of CLL cells on the flow cytometer. 相似文献
30.