全文获取类型
收费全文 | 479篇 |
免费 | 24篇 |
国内免费 | 34篇 |
专业分类
儿科学 | 17篇 |
妇产科学 | 1篇 |
基础医学 | 61篇 |
口腔科学 | 8篇 |
临床医学 | 50篇 |
内科学 | 84篇 |
皮肤病学 | 6篇 |
神经病学 | 5篇 |
特种医学 | 170篇 |
外科学 | 36篇 |
综合类 | 19篇 |
预防医学 | 34篇 |
眼科学 | 11篇 |
药学 | 15篇 |
中国医学 | 1篇 |
肿瘤学 | 19篇 |
出版年
2024年 | 1篇 |
2022年 | 2篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 7篇 |
2012年 | 7篇 |
2011年 | 11篇 |
2010年 | 21篇 |
2009年 | 37篇 |
2008年 | 26篇 |
2007年 | 35篇 |
2006年 | 32篇 |
2005年 | 29篇 |
2004年 | 16篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 18篇 |
2000年 | 6篇 |
1999年 | 17篇 |
1998年 | 27篇 |
1997年 | 33篇 |
1996年 | 21篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 13篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 19篇 |
1987年 | 7篇 |
1986年 | 11篇 |
1985年 | 5篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1976年 | 1篇 |
1975年 | 3篇 |
排序方式: 共有537条查询结果,搜索用时 15 毫秒
71.
72.
Sonographic breast imaging has been useful in the differentiation of cystic from solid masses. It has also been helpful in the characterization of palpable breast masses in the absence of corresponding abnormalities. The authors undertook a prospective study that incorporated pulsed Doppler analysis into sonographic real-time imaging of solid breast masses. Thirty-eight patients were examined. In 12 of the patients there were positive Doppler signals, while in 26 patients there were no Doppler signals. The 12 patients showing positive Doppler signals proved to have infiltrating ductal carcinoma, while the 26 patients with negative Doppler signals proved to have benign breast disorders. Pulsed Doppler analysis as a supplement to sonographic real-time imaging shows promise for the identification of breast carcinoma. 相似文献
73.
Turner DA; Alcorn FS; Shorey WD; Stelling CB; Mategrano VC; Merten CW; Silver B; Economou SG; Straus AK; Witt TR 《Radiology》1988,168(1):49-58
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer. 相似文献
74.
75.
Lalit?DandonaEmail author Pratap?Sisodia SG?Prem?Kumar YK?Ramesh A?Anod?Kumar M?Chalapathi?Rao Elliot?Marseille M?Someshwar Nell?Marshall James?G?Kahn 《BMC public health》2005,5(1):98
Background
Female sex workers and their clients play a prominent role in the HIV epidemic in India. Systematic data on the outputs, cost and efficiency for HIV prevention programmes for female sex workers in India are not readily available to understand programme functioning and guide efficient use of resources. 相似文献76.
Elisa?Lloyd-Smith Thomas?Kerr Robert?S?Hogg Kathy?Li Julio?SG?Montaner Evan?WoodEmail author 《Harm reduction journal》2005,2(1):24
Recent studies have indicated that injection-related infections such as abscesses and cellulitis account for the majority
of emergency room visits and acute hospitalizations accrued by local injection drug users. The objective of this analysis
was to examine the prevalence and correlates of developing an abscess among a cohort of injection drug users in Vancouver
and to identify socio-demographic and drug use variables associated with abscesses at baseline. We examined abscesses among
participants enrolled in a prospective cohort of injection drug users. Categorical variables were analyzed using the Pearson's
chi-square test and continuous variables were analyzed using the Wilcoxon signed rank test. Among 1 585 baseline participants,
341 (21.5%) reported having an abscess in the last six months. In a logistic regression model that adjusted for all variables
that were associated with having an abscess at p < 0.1 in univariate analyses, female gender [odds ratio (OR) = 1.7, [95%CI:
1.2 – 2.4]; p = 0.002), recent incarceration (OR = 1.7, [95%CI: 1.3 – 2.2]; p < 0.001), sex trade involvement (OR = 1.4 [95%
CI: 1.0 – 2.0]; p = 0.03), frequent cocaine use (OR = 1.5 [95%CI: 1.2 – 2.0]; p = 0.002) and HIV serostatus (OR = 1.5, [95%CI:
1.2 – 2.0]; p = 0.003) were positively associated with having an abscess. Explanations for these associations require further
study, and interventions are needed to address this highly prevalent concern. 相似文献
77.
Background
Relatively little is known about the incidence of prescribing errors and there has been no work on this in a single specialty ophthalmic hospital. Knowing where and when errors are most likely to occur is generally felt to be the first step in trying to prevent these errors. This study is an attempt in, the setting of an eye hospital, to try to identify and attribute these medication errors. 相似文献78.
79.
80.
Qiu X Hodges S Lukaszewska T Hino S Arai H Yamaguchi J Swanson P Schochetman G Devare SG 《Journal of medical virology》2008,80(3):484-493
Screening blood donations for human T-lymphotropic virus types I and II (HTLV-I/II) continues to be important in protecting the safety of blood products and controlling the global spread of these retroviruses. We have developed a fully automated, third generation chemiluminescent immunoassay, ARCHITECT rHTLV-I/II, for detection of antibodies to HTLV-I/II. The assay utilizes recombinant proteins and synthetic peptides and is configured in a double antigen sandwich assay format. Specificity of the assay was 99.98% (9,254/9,256, 95% CI = 99.92-100%) with the negative specimens from the general population including blood donors, hospital patients and pregnant women from the US, Japan and Nicaragua. The assay demonstrated 100% sensitivity by detecting 498 specimens from individuals infected with HTLV-I (n = 385) and HTLV-II (n = 113). ARCHITECT rHTLV-I/II results were in complete agreement with the Murex HTLV-I/II reference assay and 99.7% agreement with the Genelabs HTLV Blot 2.4 confirmatory assay. Analytical sensitivity of the assay was equivalent to Murex HTLV-I/II assay based on end point dilutions. Furthermore, using a panel of 397 specimens from Japan, the ARCHITECT rHTLV-I/II assay exhibited distinct discrimination between the antibody negative (Delta Value = -7.6) and positive (Delta Value = 7.6) populations. Based on the excellent specificity and sensitivity, the new ARCHITECT rHTLV-I/II assay should be an effective test for the diagnosis of HTLV-I/II infection and also for blood donor screening. 相似文献