全文获取类型
收费全文 | 1495篇 |
免费 | 95篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 28篇 |
妇产科学 | 6篇 |
基础医学 | 147篇 |
口腔科学 | 1篇 |
临床医学 | 124篇 |
内科学 | 540篇 |
皮肤病学 | 13篇 |
神经病学 | 159篇 |
特种医学 | 47篇 |
外科学 | 280篇 |
综合类 | 15篇 |
预防医学 | 65篇 |
眼科学 | 5篇 |
药学 | 45篇 |
肿瘤学 | 89篇 |
出版年
2023年 | 9篇 |
2022年 | 12篇 |
2021年 | 31篇 |
2020年 | 31篇 |
2019年 | 29篇 |
2018年 | 36篇 |
2017年 | 25篇 |
2016年 | 47篇 |
2015年 | 51篇 |
2014年 | 56篇 |
2013年 | 58篇 |
2012年 | 91篇 |
2011年 | 90篇 |
2010年 | 56篇 |
2009年 | 48篇 |
2008年 | 80篇 |
2007年 | 92篇 |
2006年 | 90篇 |
2005年 | 87篇 |
2004年 | 78篇 |
2003年 | 94篇 |
2002年 | 86篇 |
2001年 | 36篇 |
2000年 | 47篇 |
1999年 | 37篇 |
1998年 | 14篇 |
1997年 | 15篇 |
1996年 | 6篇 |
1995年 | 12篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 13篇 |
1991年 | 11篇 |
1990年 | 7篇 |
1989年 | 17篇 |
1988年 | 14篇 |
1987年 | 9篇 |
1986年 | 10篇 |
1985年 | 10篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1943年 | 3篇 |
1936年 | 4篇 |
1933年 | 3篇 |
1929年 | 4篇 |
1928年 | 2篇 |
1927年 | 2篇 |
1926年 | 2篇 |
1922年 | 2篇 |
1909年 | 2篇 |
排序方式: 共有1603条查询结果,搜索用时 13 毫秒
1.
Julie A. Schmidt Georgina K. Fensom Sabina Rinaldi Augustin Scalbert Paul N. Appleby David Achaintre Audrey Gicquiau Marc J. Gunter Pietro Ferrari Rudolf Kaaks Tilman Kühn Heiner Boeing Antonia Trichopoulou Anna Karakatsani Eleni Peppa Domenico Palli Sabina Sieri Rosario Tumino Bas Bueno-de-Mesquita Antonio Agudo Maria-Jose Sánchez María-Dolores Chirlaque Eva Ardanaz Nerea Larrañaga Aurora Perez-Cornago Nada Assi Elio Riboli Konstantinos K. Tsilidis Timothy J. Key Ruth C. Travis 《International journal of cancer. Journal international du cancer》2020,146(3):720-730
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer. 相似文献
2.
Beta2-Microglobulin 总被引:1,自引:0,他引:1
Among the uremic toxins in the "middle molecule" range, beta2-microglobulin (β2-M) is certainly one of the most frequently studied compounds. Its serum level increases with the progression of chronic kidney disease, to reach very high concentrations in patients with end-stage kidney disease. It is the major protein component of dialysis-related amyloidosis, a dramatic complication which results from high extracellular concentration and posttranslational modification of β2-M and a number of other promoters of amyloid fibril formation and deposition in osteo-articular tissues. Effective removal of β2-M can be achieved with highly effective hemodialysis and hemodiafiltration techniques but predialysis session serum levels cannot be normalized. The prevalence and severity of β2-M amyloidosis appear to have decreased in the last 20 years, although its occurrence may simply be delayed. 相似文献
3.
4.
5.
Extracorporeal shock wave lithotripsy of gall stones: an in vitro comparison between an electrohydraulic and a piezoceramic device. 下载免费PDF全文
R Schachler N C Bird T Sauerbruch E A Frost M Sackmann G Paumgartner A G Johnson 《Gut》1991,32(3):312-315
A comparative study of the effectiveness of two types of lithotripter in fragmenting gall bladder stones is reported. The machines used were a Piezolith 2300, which generates shock waves by the piezoceramic principle, and a Dornier MPL 9000, which produces the shock waves by underwater spark discharge. With each machine, corresponding stones of 45 pairs of weight and volume matched calculi (median volume 0.5 cm3, median diameter 10.5 mm) obtained at cholecystectomy were treated. All stones were successfully disintegrated (fragments smaller than 2 mm) with up to 5400 (median 628) shocks with the Piezolith and 3450 (median 428) shocks with the MPL 9000 lithotripters. With the Piezolith, operating at the highest power setting, a 1.65 fold median higher number of shocks was required for stone fragmentation than with the MPL 9000 at a medium power setting. Stone volume seemed to be the only determinant which affected ease of fragmentation; composition and density of the stones as assessed by computed tomography did not seem to be governing factors. 相似文献
6.
7.
As editors we want as many people to have access to NDT as possible.The last 18 months have seen a number of experimental initiativesto test the technical and logistical 相似文献
8.
Dr. Juergen Pauletzki MD Joseph Holl MD Michael Sackmann MD Michael Neubrand MD Ulrich Klueppelberg MD Tilman Sauerbruch MD Gustav Paumgartner MD 《Digestive diseases and sciences》1995,40(8):1775-1781
To determine the rate and characteristics of gallstone recurrence after direct contact dissolution with methyltert-butyl ether, 60 consecutive patients were followed for up to 4.5 years (median 2.2 years) after complete disappearance of all stone residues and debris and cessation of adjuvant bile acid therapy. Initial gallstones had been multiple in all but four patients. Twenty-eight of the 60 patients developed recurrent gallstones. The cumulative risk of gallstone recurrence (actuarial analysis) was 23±6%, 34±7%, 55±8%, and 70±9% at one, two, three, and four years, respectively. The recurrent stones were usually multiple and small (6±4 mm). Gallstone recurrence was associated with recurrent biliary pain in two patients, one of whom developed acute cholecystitis. Recurrent stones were cleared completely by bile acid medication with or without shock-wave lithotripsy in 61±15% of patients at one year (actuarial analysis). In conclusion, gallstone recurrence after successful contact dissolution of multiple stones with methyltert-butyl ether has to be expected in a high percentage of patients. Most patients, however, remain free of biliary pain during long-term follow-up. 相似文献
9.
Topographic association between active gastritis and Campylobacter pylori colonisation. 总被引:13,自引:3,他引:13 下载免费PDF全文
E Bayerd?rffer H Oertel N Lehn G Kasper G A Mannes T Sauerbruch M Stolte 《Journal of clinical pathology》1989,42(8):834-839
One thousand biopsy specimens obtained from 10 sites in the stomachs of 50 patients were examined for the presence of active chronic gastritis and Campylobacter pylori. All 32 patients with active chronic gastritis at 234 out of 320 sites were positive for C pylori: 227 showed colonisation with C pylori by the Warthin-Starry stain; and 222 were positive by culture. C pylori was not found in 18 patients with inactive chronic gastritis or histologically normal mucosa. The area of C pylori colonisation was larger than the area of active chronic gastritis in 289 positive specimens on culture and 261 on staining, respectively, suggesting that C pylori colonisation may precede the development of active chronic gastritis. It is concluded that patchy distribution of active chronic gastritis and C pylori colonisation must be considered, particularly in serology or breath test studies where the histological examination serves as a reference. Furthermore, it may have important implications for the follow up of patients after antibacterial treatment. The topographic and specific association of C pylori and active chronic gastritis provides further evidence for the pathogenic role of C pylori in active chronic gastritis. 相似文献
10.