全文获取类型
收费全文 | 1683916篇 |
免费 | 129829篇 |
国内免费 | 7111篇 |
专业分类
耳鼻咽喉 | 21360篇 |
儿科学 | 53621篇 |
妇产科学 | 43872篇 |
基础医学 | 232260篇 |
口腔科学 | 47948篇 |
临床医学 | 147862篇 |
内科学 | 352797篇 |
皮肤病学 | 40684篇 |
神经病学 | 140541篇 |
特种医学 | 66053篇 |
外国民族医学 | 387篇 |
外科学 | 252840篇 |
综合类 | 33558篇 |
现状与发展 | 3篇 |
一般理论 | 518篇 |
预防医学 | 140620篇 |
眼科学 | 34792篇 |
药学 | 117105篇 |
5篇 | |
中国医学 | 3454篇 |
肿瘤学 | 90576篇 |
出版年
2021年 | 15054篇 |
2019年 | 15545篇 |
2018年 | 23772篇 |
2017年 | 17877篇 |
2016年 | 19874篇 |
2015年 | 22363篇 |
2014年 | 29594篇 |
2013年 | 43718篇 |
2012年 | 59292篇 |
2011年 | 62344篇 |
2010年 | 36258篇 |
2009年 | 33640篇 |
2008年 | 55670篇 |
2007年 | 59357篇 |
2006年 | 58912篇 |
2005年 | 57744篇 |
2004年 | 54794篇 |
2003年 | 52329篇 |
2002年 | 48108篇 |
2001年 | 74532篇 |
2000年 | 76443篇 |
1999年 | 64286篇 |
1998年 | 18790篇 |
1997年 | 16749篇 |
1996年 | 17653篇 |
1995年 | 17624篇 |
1994年 | 16377篇 |
1993年 | 15266篇 |
1992年 | 51642篇 |
1991年 | 50093篇 |
1990年 | 47983篇 |
1989年 | 45669篇 |
1988年 | 42363篇 |
1987年 | 41350篇 |
1986年 | 39074篇 |
1985年 | 37561篇 |
1984年 | 28560篇 |
1983年 | 23922篇 |
1982年 | 14894篇 |
1981年 | 13330篇 |
1979年 | 25355篇 |
1978年 | 18276篇 |
1977年 | 15475篇 |
1976年 | 14092篇 |
1975年 | 14875篇 |
1974年 | 17401篇 |
1973年 | 16721篇 |
1972年 | 15389篇 |
1971年 | 14213篇 |
1970年 | 13051篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Victor Aboyans Louis Labrousse Philippe Lacroix Jér?me Guilloux Seifeddine Sekkal Alexandre Le Guyader Elisabeth Cornu Marc Laskar 《European journal of cardio-thoracic surgery》2006,30(2):300-304
BACKGROUND: Despite major improvement in surgical techniques and intensive care management, stroke remains one of the most devastating complications of coronary artery bypass grafting (CABG). We aimed to determine factors predicting the occurrence of stroke during CABG. A special interest was focused on preoperative therapies. METHODS: We prospectively enrolled 810 consecutive candidates for CABG alone in a specific database, including all pre- and perioperative data (history, clinical, therapeutic, cardiac catheterization, surgical and intensive care data). Univariate tests and then multiple logistic regression analysis were used to determine independent predictive factors. RESULTS: During the first postoperative month, stroke occurred in 11 cases and transient ischemic attack (TIA) in 4 additive cases (cumulative rate: 1.85%). After the multivariate analysis, the following factors remained significant (p<0.05) in the predictive model, with corresponding odds ratios between brackets: redo cardiac surgery (7.45), unstable cardiac status (4.74), past history of cerebrovascular disease (4.14), past history of peripheral arterial disease (3.55), whereas the presence of preoperative statins was protective (0.24, 95% IC: 0.07-0.78). The addition of perioperative data (aortic calcification, postoperative arrhythmia, on/off-pump surgery) did not change the final predictive model. CONCLUSION: To our knowledge, this is the first real-world observational report highlighting the interest of statins for the prevention of stroke in the very special situation of CABG. Even though according to randomized trials coronary patients have a benefit from these drugs, a special level of interest should be directed towards those presenting the above-mentioned risk factors. 相似文献
102.
Michele D. Mignogna Stefano Fedele Lucio Lo Russo Lorenzo Lo Muzio 《Journal of oral pathology & medicine》2003,32(4):200-205
BACKGROUND: The recurrent chronic orofacial swelling caused by orofacial granulomatosis (OFG) can cause significant cosmetic and functional problems but can be prevented if the disease is diagnosed early and promptly treated. Although the enlargement of the lips is described to be the most common presenting complaint, the clinical onset of OFG may be characterized by minor associated mucosal and neurological manifestations, making early diagnosis very difficult or, sometimes, merely presumable. PATIENTS AND METHODS: We retrospectively analyzed the clinical manifestations of 19 patients with OFG, who were examined at our institution between 1998 and 2002, in order to determine their initial manifestations and presenting symptoms. RESULTS: A total of 10 patients showed classical recurrent enlargement of the lips (six lower; four upper) as presenting symptom. In the other nine patients, OFG onset was characterized by transient unilateral facial nerve palsy (two cases), intraoral manifestations (two cases), recurrent swelling of the periorbital area (two cases), of the chin (one case), of the zygomatic area (one case), and of the cheeks (one case). CONCLUSION: Our data underlined that OFG onset could be frequently characterized by widely variable, multiform, and temporary clinical findings. Involvement of atypical sites of the orofacial region and presence of single minor manifestations may occur as presenting symptoms, often preceding the development of traditional clinical findings. 相似文献
103.
Summary The third-stage larvae of Daniconema anguillae Moravec et K?ie, 1987 are found in the eels fins caught from Dringis Lake (Lithuanian National park). The morphology of these
larvae is briefly described. 相似文献
104.
O Schouten J H H van Laanen E Boersma R Vidakovic H H H Feringa M Dunkelgrün J J Bax J Koning H van Urk D Poldermans 《European journal of vascular and endovascular surgery》2006,32(1):21-26
OBJECTIVE: To evaluate the effect of statins on aneurysm growth in a group of consecutive patients under surveillance for infrarenal aortic aneurysms (AAA). MATERIALS AND METHODS: All patients (59 statin users, 91 non-users) under surveillance between January 2002 and August 2005 with a follow-up for aneurysm growth of at least 12 months and a minimum of three diameter evaluations were retrospectively included in the analysis. Multiple regression analysis, weighted with the number of observations, was performed to test the influence of statins on AAA growth rate. RESULTS: During a median period of 3.1 (1.1-13.1) years the overall mean aneurysm growth rate was 2.95+/-2.8 mm/year. Statin users had a 1.16 mm/year lower AAA growth rate compared to non-users (95% CI 0.33-1.99 mm/year). Increased age was associated with a slower growth (-0.09 mm/year per year, p = 0.003). Female gender (+1.82 mm/year, p = 0.008) and aneurysm diameter (+0.06 mm/year per mm, p = 0.049) were associated with increased AAA growth. The use of non-steroidal anti-inflammatory drugs, chronic lung disease, or other cardiovascular risk factors were not independently associated with AAA growth. CONCLUSIONS: Statins appear to be associated with attenuation of AAA growth, irrespective of other known factors influencing aneurysm growth. 相似文献
105.
Paul C. Willems Leon Elmans Patricia G. Anderson Wilco C. H. Jacobs Dick B. van der Schaaf Marinus de Kleuver 《European spine journal》2006,15(10):1487-1494
The results of lumbar fusion in chronic low back pain (LBP) patients vary considerably, and there is a need for proper patient selection. Lumbosacral orthoses have been widely used to predict outcome, however, with little scientific support. The aim of the present study was to determine the value of a pantaloon cast test in selecting chronic LBP patients for lumbar fusion or conservative management. First, a systematic review of the literature was carried out in which two independent reviewers identified studies in Medline, Cochrane and Current Contents databases. Three papers met the selection criteria. In the only study with a control group, a significantly better outcome after fusion compared to conservative treatment was found in patients who reported significant pain relief while in a cast (i.e. a positive cast test). The results of lumbar fusion, however, were not significantly different for patients with a positive and those with a negative cast test. In addition to the review, a clinical cohort study of 257 LBP patients, who had been allocated to either lumbar fusion or conservative management by a temporary external transpedicular fixation trial, was performed. Prior to allocation, all had undergone a pantaloon cast test. Patients with no history of prior spine surgery and with a positive pantaloon cast test had a better outcome after lumbar fusion than those treated conservatively (P = 0.002, χ
2 test). In patients with previous spine operations the outcomes were poor and the test was of no value. From the literature and the present patient cohort, it was concluded that only in chronic LBP patients without prior spine surgery, a pantaloon cast test with substantial pain relief suggests a favorable outcome of lumbar fusion compared to conservative management. The test has no value in patients who have had previous spine surgery. 相似文献
106.
107.
目的:通过16例经内窥镜及病理证实为Barrett食管的钡餐检查表现,初步探讨Barrett食管及其并发症放射学检查的意义。方法:回顾性分析16例Barrett食管的内窥镜和气钡检查的记录及表现,着重探讨气钡检查的X线表现。结果:食管内窥镜和组织学检查全部病例均有炎症改变,其他可见胃食管反流、食管溃疡和食管腺癌。放射学钡餐检查结果:Barrett食管炎4例,Barrett食管溃疡7例,Barrett食管癌5例。结论:Barrett食管及其并发症至今无明确放射学征象,改进对“Z”线的检查技术和方法,有可能提高其发现率。钡餐发现胃食管反流、食管裂孔疝同时并发食管炎、食管溃疡及食管癌者均应考虑到本症的可能。 相似文献
108.
109.
Philippe Nickers Luc Coppens Jean de Leval Nicolas Jansen Jean-Marie Deneufbourg 《Radiotherapy and oncology》2006,79(3):329-334
BACKGROUND AND PURPOSE: To evaluate on 201 locally advanced prostatic cancers prospectively treated in a phase II trial, the efficacy of a combination of external beam radiotherapy (39.6 Gy) and (192)Ir low dose rate brachytherapy (Bt) (40-45 Gy). PATIENTS AND METHODS: Sixty-four patients were included in the intermediate prognosis group with only one of the following adverse factors (PSA > 10 ng/ml, Gleason score > or = 7 or clinical stage > or =T2b) and 137 in the unfavourable group when at least two of these factors were present. RESULTS: The actuarial 4 years biochemical no evidence of disease is 82.8% for the entire population. It is, respectively, 97 and 76% in the intermediate and unfavourable prognosis groups (P < 0.0001). Grade > or =3 late urinary complications occurred in 13 patients (6.5%). Eight patients (4%) presented late grade 2 rectal complications but no grades 3-5 was observed. CONCLUSIONS: Even if an alpha/beta of 1.5-3 Gy theoretically favours the use of a high dose rate mode of irradiation, the early results presented here are as good as those reported for similar groups of patients with high dose rate treatments. Late toxicity is identical but our urinary toxicity is within the less favourable and rectal toxicity within the most favourable results. We can postulate that while inducing very high hyperdosage regions (V150) mainly focused on the peripheral zone, most of the Bt techniques consist of a more ablative treatment. Many of the radiobiological studies on Bt did not in fact take into account the heterogeneity of irradiation inside the CTV. This study highlights the need to explore pulsed dose rate therapies, permanent implant and new available radioisotopes such as (169)Ytterbium that will offer the safety of low and lower dose rates. The actual late toxicity of the different Bt techniques is not yet inexistent indeed. 相似文献
110.
Lisa A. Lang DDS MS David C. Holmes DDS MS Craig Passon DDS MS Robert M. Trombly DDS JD Jeffrey D. Astroth DDS MSPH Arnold F. Tavel DMD 《Journal of prosthodontics》2003,12(3):206-210
Using complete denture treatment as an introduction to clinical patient care for dental students, the purposes of the Complete Denture Prosthodontics Transition Clinic at the University of Colorado School of Dentistry are to reduce the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience, and to encourage development of student self-confidence and skills. In the 2002 spring semester, faculty at the University of Colorado School of Dentistry initiated the Complete Denture Prosthodontics Transition Clinic for DS-II (second-year) dental students, as an introduction to clinical patient care. Each patient was assigned to a team of two dental students. Three Division of Prosthodontics faculty members staffed each clinic session, providing a student-to-faculty ratio of approximately 6.6:1 and a patient-to-faculty ratio of approximately 3.3:1. All DS-II students in the Class of 2004 delivered their first complete dentures no later than 8 months (average, 184 days) after the last day of the preclinical complete denture prosthodontics course. The time from the diagnostic appointment through the denture placement appointment averaged 39 days for patients treated in this program, compared with an average of 98 days or more for previous classes. The program was successful in achieving the goal of reducing the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience. 相似文献