全文获取类型
收费全文 | 66384篇 |
免费 | 4638篇 |
国内免费 | 215篇 |
专业分类
耳鼻咽喉 | 821篇 |
儿科学 | 1540篇 |
妇产科学 | 962篇 |
基础医学 | 8390篇 |
口腔科学 | 1007篇 |
临床医学 | 7092篇 |
内科学 | 14112篇 |
皮肤病学 | 824篇 |
神经病学 | 6595篇 |
特种医学 | 2300篇 |
外国民族医学 | 5篇 |
外科学 | 11778篇 |
综合类 | 709篇 |
一般理论 | 48篇 |
预防医学 | 4595篇 |
眼科学 | 1246篇 |
药学 | 4588篇 |
中国医学 | 86篇 |
肿瘤学 | 4539篇 |
出版年
2024年 | 66篇 |
2023年 | 507篇 |
2022年 | 883篇 |
2021年 | 2045篇 |
2020年 | 1238篇 |
2019年 | 1827篇 |
2018年 | 2225篇 |
2017年 | 1574篇 |
2016年 | 1663篇 |
2015年 | 1915篇 |
2014年 | 2744篇 |
2013年 | 3444篇 |
2012年 | 5369篇 |
2011年 | 5553篇 |
2010年 | 2991篇 |
2009年 | 2739篇 |
2008年 | 4483篇 |
2007年 | 4579篇 |
2006年 | 4371篇 |
2005年 | 4180篇 |
2004年 | 3724篇 |
2003年 | 3560篇 |
2002年 | 3176篇 |
2001年 | 508篇 |
2000年 | 409篇 |
1999年 | 472篇 |
1998年 | 638篇 |
1997年 | 503篇 |
1996年 | 398篇 |
1995年 | 336篇 |
1994年 | 304篇 |
1993年 | 284篇 |
1992年 | 248篇 |
1991年 | 212篇 |
1990年 | 183篇 |
1989年 | 171篇 |
1988年 | 173篇 |
1987年 | 130篇 |
1986年 | 129篇 |
1985年 | 116篇 |
1984年 | 140篇 |
1983年 | 112篇 |
1982年 | 117篇 |
1981年 | 113篇 |
1980年 | 121篇 |
1979年 | 60篇 |
1978年 | 61篇 |
1977年 | 54篇 |
1976年 | 39篇 |
1975年 | 41篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
William V. Giannobile Rafaél A Hernandez Richard D. Finkelman Susan Ryarr Christopher P. Kiritsy Mark D'Andrea Samuel E. Lynch 《Journal of periodontal research》1996,31(5):301-312
Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodontal regeneration. The objective of this study was to further characterize the biological effects of this combination of growth factors in non-human primates and compare the effects to those of each growth factor individually. Ligature-induced periodontitis was initiated in 10 cynomolgus monkeys. After periodontal lesions were established, surgery was performed, and either a methylcellulose gel vehicle or vehicle containing 10 μg each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assessed by histomorphometry. At both 4 and 12 wk vehicle-treated lesions generally revealed minimal osseous defect fill (ODF) (8.5±2.1% and 14.5±5.7%, respectively) and new attachment (NA) (34.1±5.2% and 26.6±10.5%, respectively). IGF-I treatment did not significantly alter healing compared to vehicle in any parameter at both 4 and 12 wk. PDGFBB-treated sites exhibited significant (p<0.05) regeneration of NA (69.6±12.0%) at 12 wk; trends for PDGF-BB treatment effect were also observed in other parameters at 4 and 12 wk. although these increases were not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6±5.1 % and 42.5±8.3% ODF at 4 and 12 wk, respectively, and 64.1±7.7% and 74.6±7.4% NA at 4 and 12 wk, respectively (all significantly greater than vehicle, p<0.05). The results from this study demonstrated that: 1) IGF-1 alone at the dose tested did not significantly alter periodontal wound healing; 2) PDGF-BB alone significantly stimulated NA, with trends of effect on other parameters; and 3) the PDGF-BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk. 相似文献
92.
Andrew R. Hoellein MD Christopher A. Feddock MD Charles H. Griffith III MD MSPH John F. Wilson PhD Donald R. Barnett MD MSPH Pat F. Bass III MD MS T. Shawn Caudill MD MSPH 《Journal of general internal medicine》2004,19(5P2):562-565
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education. 相似文献
93.
94.
95.
Hamid R Djalilian Saswata Roy Aaron G Benson Christopher Regala Timothy B McDonald Tina Leman 《Otology & neurotology》2005,26(4):674-677
OBJECTIVE: Given the associated risk of general anesthesia in elderly patients with cardiovascular disease, the authors set out to determine the feasibility of transcanal cochlear implantation under local anesthesia with monitored anesthesia care. METHODS: A 70-year-old man with a history of coronary artery bypass grafting, diabetes mellitus, and an American Society of Anesthesiologists Class III cardiac status underwent cochlear implantation under local with monitored anesthesia care. RESULT: With the described technique and regimen of intravenous remifentanil and dexmedetomidine, the patient tolerated the 60-minute procedure without tachycardia, hyper- or hypotension, or cardiac ischemia. CONCLUSION: Cochlear implantation using the pericanal electrode technique performed under local anesthesia with monitored anesthesia care is possible in patients at risk for undergoing general anesthesia for cochlear implantation. 相似文献
96.
Christopher L. Knight MD Henry A. Sakowski MD Bruce L. Houghton MD Mary B. Laya MD MPH Dawn E. DeWitt MD MSc 《Journal of general internal medicine》2004,19(5P2):594-598
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers. 相似文献
97.
98.
99.
Christopher R Pryce Andrea C Dettling Marianne Spengler Christian R Schnell Joram Feldon 《Neuropsychopharmacology》2004,56(2):72-79
BACKGROUND: Early environment is a major determinant of long-term mental health, evidenced by the relationship between early-life neglect or abuse and chronically increased vulnerability to developmental psychopathology, including major depressive disorder (MDD). Animal studies can increase understanding of environmentally mediated causal risk processes. We describe how daily deprivation of biological parenting in primate infants disrupts development of homeostatic and reward systems central to MDD. METHODS: Nine breeding pairs of marmoset monkeys provided control twins (CON) and early-deprived twins (ED); the latter were socially isolated for 30-120 min/day on days 2-28. During the first year of life, basal urinary norepinephrine (NE) titers and cardiophysiologic activity were measured. At the end of year 1 (adolescence), automated neuropsychologic tests were conducted to measure responsiveness to changes in stimulus-reward association (simple/reversed visual discrimination learning) and to reward per se (progressive ratio [PR] reinforcement schedule). RESULTS: The ED monkeys exhibited increased basal urinary NE titers and increased systolic blood pressure relative to CON siblings. The ED monkeys required more sessions to reinstate stimulus-oriented behavior following reversal, suggesting increased vulnerability to perceived loss of environmental control; ED monkeys also performed less PR operant responses, indicating that reward was less of an incentive and that they were mildly anhedonic relative to CON. CONCLUSIONS: In marmoset monkeys, neglect-like manipulation of ED leads to chronic changes in homeostatic systems, similar to those in children and adolescents exposed to early-life adversity and in MDD, and to responses to environmental stimuli similar to those that characterize MDD. 相似文献
100.