全文获取类型
收费全文 | 2740篇 |
免费 | 126篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 72篇 |
妇产科学 | 72篇 |
基础医学 | 292篇 |
口腔科学 | 127篇 |
临床医学 | 254篇 |
内科学 | 656篇 |
皮肤病学 | 44篇 |
神经病学 | 158篇 |
特种医学 | 366篇 |
外科学 | 273篇 |
综合类 | 17篇 |
预防医学 | 96篇 |
眼科学 | 16篇 |
药学 | 179篇 |
中国医学 | 4篇 |
肿瘤学 | 253篇 |
出版年
2022年 | 12篇 |
2021年 | 37篇 |
2020年 | 32篇 |
2019年 | 40篇 |
2018年 | 54篇 |
2017年 | 28篇 |
2016年 | 34篇 |
2015年 | 47篇 |
2014年 | 62篇 |
2013年 | 78篇 |
2012年 | 119篇 |
2011年 | 119篇 |
2010年 | 59篇 |
2009年 | 98篇 |
2008年 | 77篇 |
2007年 | 99篇 |
2006年 | 108篇 |
2005年 | 134篇 |
2004年 | 137篇 |
2003年 | 86篇 |
2002年 | 72篇 |
2001年 | 80篇 |
2000年 | 79篇 |
1999年 | 62篇 |
1998年 | 70篇 |
1997年 | 58篇 |
1996年 | 78篇 |
1995年 | 75篇 |
1994年 | 44篇 |
1993年 | 48篇 |
1992年 | 41篇 |
1991年 | 42篇 |
1990年 | 60篇 |
1989年 | 71篇 |
1988年 | 68篇 |
1987年 | 56篇 |
1986年 | 49篇 |
1985年 | 56篇 |
1984年 | 38篇 |
1983年 | 30篇 |
1982年 | 34篇 |
1981年 | 29篇 |
1980年 | 16篇 |
1979年 | 13篇 |
1978年 | 11篇 |
1977年 | 34篇 |
1976年 | 21篇 |
1975年 | 18篇 |
1971年 | 11篇 |
1969年 | 9篇 |
排序方式: 共有2891条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
John B. Mailhes Marilyn J. Aardema Francesco Marchetti 《Environmental and molecular mutagenesis》1993,22(2):107-114
The various causative and mechanistic phenomena associated with aneuploidy induction require considerable investigation to better understand the etiology of chromosome missegregation. We investigated the potential of vinblastine sulfate, pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate to induce numerical and structural chromosome changes in female mouse germ cells. Superovulated ICR mice were administered the compounds either by intraperitoneal injection or oral gavage, and oocytes were collected and processed for cytogenetic analysis 17 hr later. Vinblastine sulfate, administered i.p., induced a significant increase in the frequency of ovulated Ml oocytes and of hyperploid Mll oocytes compared to controls, but did not increase the frequency of structural aberrations. Pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate did not increase the frequency of numerical or structural chromosome changes in female mouse germ cells. © 1993 Wiley-Liss, Inc. 相似文献
5.
Twenty-eight osteosarcomas (OS) of the jaw were reported. There were 15 male and 13 female patients (age range, 9 to 68 years; mean, 36.9 years); 57.1% of the patients were older than 30 years of age. Swelling was the most frequent symptom; it was reported on an average of 6 months before diagnosis. Most of the tumors of the maxilla (eight patients) occurred in the alveolar ridge (six of eight). In the mandible (20 patients), the body was the preferred site (11 of 20). Radiographically most of the lesions were either lytic and sclerotic or only lytic. Histologically, 12 cases (42.9%) were osteoblastic osteosarcoma, ten (35.8%) were chondroblastic, four (14.3%) were fibroblastic, and two (7%) were round cell OS. Of the 28 cases, three (10.7%) were low grade, and 25 (89.3%) were high grade. Thirteen patients had intralesional surgery, and 13 had marginal surgery as their initial treatment. Recurrence was the rule in the first group, and it was 69% in the second group. Twenty patients (71%) died, and eight are alive. Of these, two are alive with disease. In the six patients who are alive and disease-free, all but one had marginal to wide surgical margins at the time of the first procedure or wide margins at the time of the recurrences along with chemotherapy or radiation therapy. In the patient in which the surgical margins were marginal, the lesion was small 2.5 X 2 cm. This patient was alive without evidence of disease after 9 years of follow-up. 相似文献
6.
7.
8.
Livio Presutti Matteo Alicandri Ciufelli Daniele Marchioni Domenico Villari Alessio Marchetti Francesco Mattioli 《Otolaryngology--head and neck surgery》2007,136(3):369-372
OBJECTIVE: The aim of this paper was to describe our surgical technique for the treatment of nasal septal perforations. STUDY AND DESIGN: We studied 31 patients with nasal septal perforation treated with an endoscope-assisted technique, based on a bilateral dissection of monopedicled mucosal flaps from the nasal fossa floor, sutured at the edge of the perforation previously unstuck, without any graft interposed between the two mucosal layers. RESULTS: In our experience with 31 patients, the use of this technique led to the persistent closing (with follow-up for at least one year) of 96.3% of the perforations smaller than 3 cm. CONCLUSIONS: Our technique has the advantage of an endonasal approach, without any external incision, and the use of monopedicled flaps from the nasal fossa floor without any graft interposition, avoiding any other surgical procedure and morbidity in the donor site of the graft. The use of nasal endoscopy permits superior precision in all surgical steps. SIGNIFICANCE: The high success rate in perforations smaller than 3 cm seems to confirm the effectiveness of this technique. 相似文献
9.
The authors have reviewed their experience with treatments of small intracranial lesions by unconventionally fractionated stereotactic radiotherapy using a 4 MV photon beam. Treatment is carried out by multiple non coplanar arc irradiation obtained rotating the target, while kept at the isocentre of a Linac, around a vertical axis. The outmost concentration of the dose within the target volume enables consistent reduction of the amount of the absorbed dose by critical structures of the intact brain. They analyse the dose distribution and the method to optimise the choice of the therapeutic dose. Finally, some radiobiological considerations are presented. 相似文献
10.