全文获取类型
收费全文 | 14021篇 |
免费 | 1305篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 183篇 |
儿科学 | 407篇 |
妇产科学 | 336篇 |
基础医学 | 1920篇 |
口腔科学 | 797篇 |
临床医学 | 1210篇 |
内科学 | 3239篇 |
皮肤病学 | 326篇 |
神经病学 | 1158篇 |
特种医学 | 656篇 |
外国民族医学 | 1篇 |
外科学 | 1950篇 |
综合类 | 123篇 |
一般理论 | 5篇 |
预防医学 | 1134篇 |
眼科学 | 246篇 |
药学 | 763篇 |
中国医学 | 43篇 |
肿瘤学 | 875篇 |
出版年
2023年 | 54篇 |
2022年 | 146篇 |
2021年 | 331篇 |
2020年 | 232篇 |
2019年 | 372篇 |
2018年 | 470篇 |
2017年 | 349篇 |
2016年 | 379篇 |
2015年 | 421篇 |
2014年 | 514篇 |
2013年 | 623篇 |
2012年 | 872篇 |
2011年 | 846篇 |
2010年 | 581篇 |
2009年 | 490篇 |
2008年 | 686篇 |
2007年 | 760篇 |
2006年 | 652篇 |
2005年 | 625篇 |
2004年 | 550篇 |
2003年 | 489篇 |
2002年 | 424篇 |
2001年 | 350篇 |
2000年 | 324篇 |
1999年 | 358篇 |
1998年 | 174篇 |
1997年 | 186篇 |
1996年 | 153篇 |
1995年 | 134篇 |
1994年 | 131篇 |
1993年 | 125篇 |
1992年 | 236篇 |
1991年 | 217篇 |
1990年 | 190篇 |
1989年 | 211篇 |
1988年 | 190篇 |
1987年 | 169篇 |
1986年 | 176篇 |
1985年 | 160篇 |
1984年 | 113篇 |
1983年 | 98篇 |
1982年 | 68篇 |
1981年 | 59篇 |
1979年 | 76篇 |
1978年 | 63篇 |
1977年 | 41篇 |
1976年 | 51篇 |
1975年 | 52篇 |
1973年 | 55篇 |
1972年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Carlos Alberto Herrero de Morais Norberti Bernardineli Roberto B Garcia Marco A H Duarte Danilo M Z Guerisoli 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(3):417-421
OBJECTIVE: The aim of this study was to evaluate the biocompatibility of Portland cement with the addition of iodoform, compared to MTA (ProRoot). STUDY DESIGN: Eighteen Wistar albino rats were divided into 3 groups of 6 animals each. Polyethylene tubes were filled either with freshly mixed MTA or Portland cement mixed with iodoform (20% wt/wt) and implanted subcutaneously. An empty tube served as control. After 7, 30, or 60 days, the implants together with the surrounding tissues were removed in blocks. Sections were evaluated for the presence and thickness of a fibrous capsule, presence of granulation tissue, and the severity of inflammatory response. Data were submitted to nonparametric statistical analysis with individual comparisons between groups at a significance level of P < 0.05. RESULTS: There were no differences between inflammatory responses at 7 and 30 days. After 60 days from surgical removal, there was significantly more tissue reaction to the MTA and Portland cement compared to the control group. CONCLUSION: There were no significant differences regarding inflammatory responses between MTA and Portland cement with iodoform after 7, 30, or 60 days. After 60 days, the fibrous capsule around the Portland cement appeared more organized than tissue surrounding MTA implants. After 60 days, there was still a significantly increased tissue reaction to the 2 cements compared to the empty polyethylene tubes. 相似文献
23.
Alcides José Branco Filho William Kondo Luis Sérgio Nassif Mariana Jorge Garcia Rafael de Almeida Tirapelle Carlos Marcelo Dotti 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(3):326-331
BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible. 相似文献
24.
25.
26.
Mark A. Trimble Salvador Borges-Neto Stuart Smallhelser Ji Chen Emily F. Honeycutt Linda K. Shaw Jaekyeong Heo Robert A. Pagnanelli E. Lindsey Tauxe Ernest V. Garcia Fabio Esteves Frank Seghatol-Eslami G. Neal Kay Ami E. Iskandrian 《Journal of nuclear cardiology》2007,14(3):298-307
Background Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and
evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement
with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission
computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The
objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients
with left ventricular dysfunction, conduction delays, and ventricular paced rhythms.
Methods and Results A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images.
Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD,
bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction
(n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were
compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between
patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms
and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects
(P=.001).
Conclusions A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in
the evaluation of patients for CRT.
This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the
primary investigator. 相似文献
27.
Lourenço T. Higa Luiza Tsuneto João L. Garcia Ana L. Falavigna-Guilherme 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2010,104(6):400-405
We evaluated anti-Toxoplasma gondii IgM-reactive pregnant women seen at a high-risk pregnancy outpatient clinic. From March 2005 to January 2008 in Paraná, Brazil, pregnant women seen by the Brazilian Public Health System, in any gestational period, who were anti-T. gondii IgM-positive, were followed. Clinical symptoms were noted, and tests performed including IgA, IgG avidity, ultrasonogram, and amniocentesis (PCR/inoculation in mice). Of 75 patients, 8 showed low, 3 intermediate and 31 high IgG avidity. Of those who underwent the avidity test, 31 (70.5%) were in the second trimester of pregnancy. Thirty-two (42.7%) pregnant women received specific treatment. Six received triple combination treatment; in three, tachyzoites were isolated, although only one was PCR-positive, showing changes in the cerebral sonogram, borderline IgA, and the Sabin tetrad. One fetus died, and one non-reactive IgM pregnant woman showed ocular recurrence. The municipality of residence, contact with cats during adulthood, and ingestion of unpasteurized milk were shown to be important risk factors. Congenital toxoplasmosis was observed in a pregnancy referred late for treatment. Follow-up of children born to mothers with diagnosed or suspected acute toxoplasmosis is crucial in the management of the changes that toxoplasmosis may cause. 相似文献
28.
29.
30.