全文获取类型
收费全文 | 1139篇 |
免费 | 48篇 |
国内免费 | 59篇 |
专业分类
儿科学 | 44篇 |
妇产科学 | 11篇 |
基础医学 | 41篇 |
口腔科学 | 15篇 |
临床医学 | 135篇 |
内科学 | 256篇 |
皮肤病学 | 32篇 |
神经病学 | 18篇 |
特种医学 | 230篇 |
外科学 | 58篇 |
综合类 | 27篇 |
预防医学 | 77篇 |
眼科学 | 9篇 |
药学 | 33篇 |
中国医学 | 2篇 |
肿瘤学 | 258篇 |
出版年
2022年 | 1篇 |
2021年 | 10篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 15篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 16篇 |
2014年 | 24篇 |
2013年 | 41篇 |
2012年 | 44篇 |
2011年 | 33篇 |
2010年 | 45篇 |
2009年 | 32篇 |
2008年 | 34篇 |
2007年 | 77篇 |
2006年 | 39篇 |
2005年 | 44篇 |
2004年 | 33篇 |
2003年 | 33篇 |
2002年 | 13篇 |
2001年 | 31篇 |
2000年 | 16篇 |
1999年 | 31篇 |
1998年 | 59篇 |
1997年 | 35篇 |
1996年 | 60篇 |
1995年 | 45篇 |
1994年 | 42篇 |
1993年 | 49篇 |
1992年 | 9篇 |
1991年 | 12篇 |
1990年 | 21篇 |
1989年 | 30篇 |
1988年 | 36篇 |
1987年 | 35篇 |
1986年 | 26篇 |
1985年 | 30篇 |
1984年 | 16篇 |
1983年 | 10篇 |
1982年 | 12篇 |
1981年 | 22篇 |
1980年 | 19篇 |
1979年 | 6篇 |
1978年 | 9篇 |
1977年 | 15篇 |
1976年 | 7篇 |
1975年 | 9篇 |
1970年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有1246条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
H W Nab M W van Beek M A Crommelin L H van der Heijden H M Kluck J W Coebergh 《Nederlands tijdschrift voor geneeskunde》1992,136(36):1765-1770
Trends in incidence, stage distribution and mortality of breast cancer were determined in the Southeastern Netherlands in 1960-1989. First and second primary breast cancers were analyzed separately. The incidence and mortality rates were age-standardised according to the European Standard Population. The incidence rate of first primary invasive breast cancer increased from 50 per 100,000 women per year in 1960-61 to 96 in 1988-89, and of second primary invasive breast cancer from 3.2 in 1965-66 to 7.8 in 1988-89. The incidence rate of first primary ductal carcinoma in situ (DCIS) increased from 0.3 per 100,000 women per year in 1975-76 to 2.8 in 1988-89 and of second primary DCIS from 0.06 in 1975-79 to 0.4 per 100,000 in 1985-89. The increase in first invasive primaries was observed in all age groups, but mostly at age 75 and over. The percentage with stage I tumours of the patients with a first primary invasive breast cancer increased from 7% in the sixties to 27% in the eighties, whereas the percentage of stage III and IV tumours combined, decreased from 39% in the sixties to 26% in the eighties. While age-adjusted incidence of first primaries almost doubled in the past thirty years, breast cancer mortality rose only slightly. However, breast cancer mortality showed a proportionate increase of total mortality from 4.5% in 1970-71 to 6.3% in 1988-89.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
7.
Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
8.
9.
10.