全文获取类型
收费全文 | 14765篇 |
免费 | 1362篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 158篇 |
儿科学 | 474篇 |
妇产科学 | 313篇 |
基础医学 | 1873篇 |
口腔科学 | 314篇 |
临床医学 | 1782篇 |
内科学 | 2955篇 |
皮肤病学 | 235篇 |
神经病学 | 1396篇 |
特种医学 | 706篇 |
外国民族医学 | 1篇 |
外科学 | 2046篇 |
综合类 | 316篇 |
一般理论 | 12篇 |
预防医学 | 1456篇 |
眼科学 | 312篇 |
药学 | 965篇 |
中国医学 | 19篇 |
肿瘤学 | 815篇 |
出版年
2021年 | 222篇 |
2020年 | 135篇 |
2019年 | 219篇 |
2018年 | 276篇 |
2017年 | 223篇 |
2016年 | 248篇 |
2015年 | 245篇 |
2014年 | 331篇 |
2013年 | 521篇 |
2012年 | 683篇 |
2011年 | 694篇 |
2010年 | 405篇 |
2009年 | 432篇 |
2008年 | 637篇 |
2007年 | 680篇 |
2006年 | 723篇 |
2005年 | 627篇 |
2004年 | 609篇 |
2003年 | 532篇 |
2002年 | 505篇 |
2001年 | 493篇 |
2000年 | 479篇 |
1999年 | 406篇 |
1998年 | 179篇 |
1997年 | 170篇 |
1996年 | 150篇 |
1995年 | 161篇 |
1994年 | 137篇 |
1993年 | 117篇 |
1992年 | 286篇 |
1991年 | 293篇 |
1990年 | 333篇 |
1989年 | 290篇 |
1988年 | 248篇 |
1987年 | 240篇 |
1986年 | 257篇 |
1985年 | 230篇 |
1984年 | 206篇 |
1983年 | 172篇 |
1982年 | 131篇 |
1981年 | 106篇 |
1980年 | 112篇 |
1979年 | 155篇 |
1978年 | 135篇 |
1977年 | 123篇 |
1976年 | 140篇 |
1975年 | 102篇 |
1974年 | 126篇 |
1972年 | 118篇 |
1970年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
21.
Comparison between traditional 2-dimensional cephalometry and a 3-dimensional approach on human dry skulls. 总被引:4,自引:0,他引:4
Gregory L Adams Stuart A Gansky Arthur J Miller William E Harrell David C Hatcher 《American journal of orthodontics and dentofacial orthopedics》2004,126(4):397-409
The cephalogram is the standard used by orthodontists to assess skeletal, dental, and soft tissue relationships. This approach, however, is based on 2-dimensional (2D) views used to analyze 3-dimensional (3D) objects. The purpose of this project was to evaluate and compare a 3D imaging system and traditional 2D cephalometry for accuracy in recording the anatomical truth as defined by physical measurements with a calibrated caliper. Thirteen skeletal landmarks were located by both radiographic methods on 9 dry human skulls. Intraclass correlation (0.995), variance (0.054 mm(2)), and standard deviation (SD) (0.237 mm) were averaged over 76 measurements and derived from precision calipers to establish these physical measurements as a reliable gold standard to make comparisons of the 2D and 3D radiographic methods. The results showed great variability of the 2D from the gold standard, with the range varying from -17.68 mm (underestimation of Gn-Zyg R) to +15.52 mm (overestimation of Zyg L-Zyg R). In contrast, the 3D method (Sculptor, Glendora, Calif) indicated a range of the SD from -3.99 (underestimation) mm to +2.96 mm (overestimation). The 3D evaluation was much more precise, within approximately 1 mm of the gold standard. These results indicate that, when the actual distance is measured on a human skull in its true dimensions of 3D space, the Sculptor program, by using a 3D method, is more precise and 4 to 5 times more accurate than the 2D approach. Evaluating distances in 3D space with a 2D image grossly exaggerates the true measure and offers a distorted view of craniofacial growth. There is an inherent problem of representing a linear measure occupying a 3D space with a 2D image. 相似文献
22.
Prof. Dr. Petra Gastmeier Prof. Dr. M. M. Hoeper Prof. Dr. M. Stoll Prof. Dr. H. A. Adams 《Intensivmedizin und Notfallmedizin》2007,44(5):270-278
Patients with imported highly contagious diseases like viral hemorrhagic fever (VHF), pneumonic plague or anthrax require special preventive measures and strict isolation. In addition, new emerging infections like severe acute respiratory syndrome (SARS) and epidemic influenza also have to be taken into account. At present five high security infectious disease units for patient care are available in Germany. Due to the relatively nonspecific symptoms, a patient with one of these infections may also be admitted to any other hospital. Therefore each hospital should develop a concept for the management and control of these lifethreatening highly contagious diseases. The present article describes the current emergency plan developed for the management of patients with highly contagious diseases at Hannover Medical School. 相似文献
23.
24.
25.
Samuel B Adams Paul R Herz Debra L Stamper Mark J Roberts Stephane Bourquin Nirlep A Patel Karl Schneider Scott D Martin Sonya Shortkroff James G Fujimoto Mark E Brezinski 《Journal of orthopaedic research》2006,24(4):708-715
The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage. 相似文献
26.
Penile plethysmography was used to examine sexual preferences of individuals accused of child molestation in the course of custody conflicts. Information regarding the alleged offenders, victims, and sex offense was gathered. In comparison to accused offenders who are not engaged in custody disputes, the subjects were more often accused of sexually abusing a younger child who was a biological relative. The source of accusations was usually the mother. Additionally, the custody-dispute subjects were less likely to have a prior criminal history. Penile tumescence data suggested that the subjects involved in custody disputes were less sexually aroused by children than those subjects who were not involved in custody conflicts. However, the results revealed that in both groups a substantial number of subjects responded equally or more to the child stimuli. In sum, the alleged offenders involved in custody disputes appeared less deviant on several measures. 相似文献
27.
28.
J. Boldt H. A. Adams B. Zickmann D. Kling G. Hempelmann 《European journal of clinical pharmacology》1990,38(5):431-436
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were
not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st
min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation
period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index
(CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV
and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an
increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%),
and RVEF (−15%) fell significantly.
It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse
cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline. 相似文献
29.
Aspiration cytologic, ultrastructural, and DNA cytometric findings of solid and papillary tumor of the pancreas. 总被引:1,自引:0,他引:1
Solid and papillary epithelial neoplasm of the pancreas (SPENP) is a rare lesion characteristically occurring in young women. By contrast with pancreatic ductal adenocarcinomas, SPENP is a slow-growing tumor that rarely metastasizes or is fatal. The current report describes light and electron microscopic and histochemical findings with DNA flow cytometric analyses of two cases of SPENP. The first patient was a 24-year-old woman; the second, a 72-year-old man. Although SPENP is rare in older men, both patients had characteristic radiographic and light microscopic features of SPENP. Ultrastructural evidence of acinar differentiation was seen in the first patient; the second patient had focal neuroendocrine differentiation. Flow cytometric analysis of the first tumor demonstrated diploid-range DNA content with a 5.8% S-phase fraction (SPF). The DNA cytometric analysis of a biopsy specimen from the second tumor revealed diploid-range DNA content with a 6.1% SPF, although subsequent sampling of the resected tumor showed an aneuploid population with a DNA index of 1.8 and SPF of 2.1%. 相似文献
30.
C Adams 《The Journal of school nursing》1991,7(2):22-25
New programs, such as care of pregnant teens and substance abuse education, are more commonplace in the school setting today. The school nurse is increasingly involved with professionals and others inside and outside the school system. Thus, the nurse's effectiveness may greatly depend upon the ability to lead others. 相似文献