全文获取类型
收费全文 | 274751篇 |
免费 | 8154篇 |
国内免费 | 245篇 |
专业分类
耳鼻咽喉 | 2385篇 |
儿科学 | 9730篇 |
妇产科学 | 5488篇 |
基础医学 | 31389篇 |
口腔科学 | 3684篇 |
临床医学 | 24548篇 |
内科学 | 49718篇 |
皮肤病学 | 2038篇 |
神经病学 | 25796篇 |
特种医学 | 12332篇 |
外国民族医学 | 46篇 |
外科学 | 40262篇 |
综合类 | 3190篇 |
一般理论 | 132篇 |
预防医学 | 28156篇 |
眼科学 | 4312篇 |
药学 | 16235篇 |
中国医学 | 834篇 |
肿瘤学 | 22875篇 |
出版年
2023年 | 506篇 |
2022年 | 916篇 |
2021年 | 1887篇 |
2020年 | 1254篇 |
2019年 | 1873篇 |
2018年 | 23853篇 |
2017年 | 18714篇 |
2016年 | 20994篇 |
2015年 | 2903篇 |
2014年 | 3423篇 |
2013年 | 5129篇 |
2012年 | 12862篇 |
2011年 | 26974篇 |
2010年 | 22422篇 |
2009年 | 14782篇 |
2008年 | 24730篇 |
2007年 | 27123篇 |
2006年 | 6118篇 |
2005年 | 7519篇 |
2004年 | 8593篇 |
2003年 | 9006篇 |
2002年 | 7144篇 |
2001年 | 2679篇 |
2000年 | 2841篇 |
1999年 | 2423篇 |
1998年 | 1503篇 |
1997年 | 1276篇 |
1996年 | 991篇 |
1995年 | 971篇 |
1994年 | 866篇 |
1993年 | 875篇 |
1992年 | 1630篇 |
1991年 | 1589篇 |
1990年 | 1556篇 |
1989年 | 1499篇 |
1988年 | 1245篇 |
1987年 | 1228篇 |
1986年 | 1160篇 |
1985年 | 1080篇 |
1984年 | 813篇 |
1983年 | 748篇 |
1982年 | 580篇 |
1981年 | 539篇 |
1980年 | 489篇 |
1979年 | 674篇 |
1978年 | 417篇 |
1977年 | 404篇 |
1975年 | 403篇 |
1974年 | 455篇 |
1973年 | 357篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
Fluid role boundaries: exploring the contribution of the advanced nurse practitioner to multi‐professional palliative care
下载免费PDF全文
![点击此处可从《Journal of clinical nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
53.
54.
55.
56.
Reem Haj-Ali BDS DDS MS ; Mary Walker DDS PhD ; Karen Williams PhD ; Yong Wang PhD ; Paulette Spencer DDS PhD 《Journal of prosthodontics》2006,15(2):82-88
PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure. 相似文献
57.
D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
58.
59.
60.
Karen Bogenschneider 《Family relations》2006,55(1):16-28
Abstract: As newcomers on college campuses, family policy courses have the potential to benefit policymaking, fill a void in undergraduate and graduate education, strengthen families, and prepare students for lifelong political engagement during a pivotal period in their development. Yet, family policy has proven a challenging course to teach. Family policy is an esoteric concept, which makes courses difficult to distinguish from other policy courses. The content of a family policy course is fluid and inherently value laden. This paper proposes course content and teaching techniques to transform these challenges into learning opportunities. The author discusses similarities and differences in teaching undergraduate and graduate courses and recommends cross‐university dialogue and resource exchange to improve the teaching of family policy in college classrooms. 相似文献