全文获取类型
收费全文 | 410篇 |
免费 | 15篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 13篇 |
妇产科学 | 5篇 |
基础医学 | 37篇 |
口腔科学 | 6篇 |
临床医学 | 38篇 |
内科学 | 78篇 |
皮肤病学 | 6篇 |
神经病学 | 28篇 |
特种医学 | 115篇 |
外科学 | 23篇 |
综合类 | 12篇 |
预防医学 | 14篇 |
眼科学 | 7篇 |
药学 | 41篇 |
肿瘤学 | 16篇 |
出版年
2020年 | 5篇 |
2018年 | 3篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 3篇 |
2011年 | 8篇 |
2010年 | 16篇 |
2009年 | 13篇 |
2008年 | 15篇 |
2007年 | 24篇 |
2006年 | 21篇 |
2005年 | 21篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 16篇 |
2000年 | 7篇 |
1999年 | 10篇 |
1998年 | 20篇 |
1997年 | 18篇 |
1996年 | 28篇 |
1995年 | 15篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 13篇 |
1988年 | 20篇 |
1987年 | 8篇 |
1986年 | 11篇 |
1985年 | 14篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1978年 | 1篇 |
1977年 | 7篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1972年 | 2篇 |
1963年 | 1篇 |
1943年 | 1篇 |
1939年 | 1篇 |
1938年 | 2篇 |
1936年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有440条查询结果,搜索用时 0 毫秒
1.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
2.
We performed a cost-effectiveness simulation of acipimox, bezafibrate, fenofibrate and gemfibrozil in patients with hyperlipoproteinaemia type IIb and IV (Frederickson). A distinction was made between patients with HLP type IIb and IV and HLP associated with diabetes mellitus type II (NIDDM). Direct costs were assessed as those incurred by social security for the treatment, and indirect costs were not taken into account. In appropriate dosages, all 4 substances can be considered equally efficacious in lowering lipid levels, although gallstones occur 3 times more frequently in patients treated with fibrates than in those treated with acipimox. Acquisition costs of the 4 drugs under consideration are comparable. Thus, when hospitalisation costs for treatment of gallstones are taken into account, therapy with acipimox is more cost effective than fibrate therapy. 相似文献
3.
P-glycoprotein-mediated drug efflux is a resistance mechanism of chronic myelogenous leukemia cells to treatment with imatinib mesylate. 总被引:16,自引:0,他引:16
T Illmer M Schaich U Platzbecker J Freiberg-Richter U Oelschl?gel M von Bonin S Pursche T Bergemann G Ehninger E Schleyer 《Leukemia》2004,18(3):401-408
Imatinib (Glivec), STI571) is an intracellular acting drug that demonstrates high activity against BCR-ABL-positive chronic myelogenous leukemia (CML) or acute lymphoblastic leukemia (ALL). However, many patients, especially with advanced disease, develop drug resistance. Here, we show by a novel high-performance liquid chromatography-based method that intracellular levels of imatinib decrease in P-glycoprotein (Pgp)-positive leukemic cells. In a model of K562 cells with gradually increasing Pgp expression, a Pgp-dependent decline of intracellular imatinib levels was observed. Decreased imatinib levels were associated with a retained phosphorylation pattern of the Bcr-Abl target Crkl and loss of effect of imatinib on cellular proliferation and apoptosis. The modulation of Pgp by cyclosporin A (CSA) readily restored imatinib cytotoxicity in these cells. Finally, we provide first data showing a biological effect of Pgp modulation in the imatinib treatment of a patient with BCR-ABL-positive ALL. MDR1 overexpression must therefore be considered as an important clinical mechanism in the diversity of resistance development to imatinib treatment. 相似文献
4.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis. 相似文献
5.
头皮糠疹是常见病是多发病,临床表现为头皮红斑和脱屑,提示皮损部位表皮结构和功能异常,头皮角质层代谢紊乱,最近对头皮糠疹病因和病理的研究证实马拉色菌,皮脂分泌和个体敏感性是形成上述皮损的3个关键因素,硫氧吡啶锌(PTZ或ZPT)可以有效地杀灭马拉色菌,PTZ的颗粒大小和形状对其在头皮的生物利用度有明显的影响。此外,PTZ的抗菌效果有赖于其分子结构的完整性,在外用制剂中加入附加的游离锌,可以有效防止PTZ解离,从而提高其疗效。 相似文献
6.
7.
8.
Jeremy YC Teoh Steffi KK Yuen James HL Tsu Charles KW Wong Brian SH Ho Ada TL Ng Wai-Kit Ma Kwan-Lun Ho Ming-Kwong Yiu 《Asian journal of andrology》2015,17(5):821-825
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted. 相似文献
9.
10.
Smokers look older than non-smokers of the same age. We have compared the concentrations of mRNA for matrix metalloproteinase 1 (MMP-1) in the buttock skin of smokers and non-smokers with quantitative real-time polymerase chain reactions. MMP-1 degrades collagen, which accounts for at least 70% of the dry weight of dermis. We report significantly more MMP-1 mRNA in the skin of smokers than non-smokers whereas no difference was seen for the tissue inhibitor of metalloproteinases 1 (TIMP-1) or the housekeeping gene GAPDH (glyceraldehyde-3-phosphate dehydrogenase). We suggest that smoking-induced MMP-1 might be important in the skin-ageing effects of tobacco smoking. 相似文献