全文获取类型
收费全文 | 42184篇 |
免费 | 4520篇 |
国内免费 | 854篇 |
专业分类
耳鼻咽喉 | 302篇 |
儿科学 | 882篇 |
妇产科学 | 548篇 |
基础医学 | 3169篇 |
口腔科学 | 1494篇 |
临床医学 | 4110篇 |
内科学 | 5403篇 |
皮肤病学 | 467篇 |
神经病学 | 3293篇 |
特种医学 | 1258篇 |
外国民族医学 | 3篇 |
外科学 | 3377篇 |
综合类 | 4742篇 |
现状与发展 | 5篇 |
一般理论 | 2篇 |
预防医学 | 7176篇 |
眼科学 | 568篇 |
药学 | 3295篇 |
25篇 | |
中国医学 | 4419篇 |
肿瘤学 | 3020篇 |
出版年
2024年 | 98篇 |
2023年 | 927篇 |
2022年 | 964篇 |
2021年 | 1767篇 |
2020年 | 1736篇 |
2019年 | 1697篇 |
2018年 | 1686篇 |
2017年 | 1611篇 |
2016年 | 1470篇 |
2015年 | 1313篇 |
2014年 | 3095篇 |
2013年 | 3136篇 |
2012年 | 2504篇 |
2011年 | 2663篇 |
2010年 | 2034篇 |
2009年 | 1951篇 |
2008年 | 2209篇 |
2007年 | 2274篇 |
2006年 | 2034篇 |
2005年 | 1704篇 |
2004年 | 1403篇 |
2003年 | 1338篇 |
2002年 | 1030篇 |
2001年 | 957篇 |
2000年 | 767篇 |
1999年 | 664篇 |
1998年 | 482篇 |
1997年 | 517篇 |
1996年 | 397篇 |
1995年 | 412篇 |
1994年 | 357篇 |
1993年 | 297篇 |
1992年 | 297篇 |
1991年 | 261篇 |
1990年 | 220篇 |
1989年 | 203篇 |
1988年 | 193篇 |
1987年 | 154篇 |
1986年 | 122篇 |
1985年 | 114篇 |
1984年 | 100篇 |
1983年 | 67篇 |
1982年 | 65篇 |
1981年 | 61篇 |
1980年 | 57篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 26篇 |
1976年 | 18篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
101.
福建省原发性肝癌遗传因素分析 总被引:4,自引:0,他引:4
为了探讨遗传因素与福建省原发性肝癌的关系,应用多种对照配对的病例对照研究方法,对100个原发性肝癌和200个对照家系进行了遗传流行病学分析。结果显示,原发性肝癌先证者一、二级亲属患病率明显高于对照组患病率,分离比为0.04146~0.08654,遗传度加权均值为63.52±4.22%。提示原发性肝癌系多基因遗传病,遗传易感性是原发性肝癌的危险因素之一,原发性肝癌的发生是遗传和环境多种因素共同作用的结果。 相似文献
102.
103.
K.A. Eaton F.M. Rimini E. Zak D.J. Brookman L.M.A. Hopkins P. J. Carmell LG. Yates C. A. Morrice B.A. Lall H. N. Newman 《Journal of clinical periodontology》1997,24(3):189-197
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth. 相似文献
104.
105.
HA Carpay P Matthijsse M Steinbuch PGH Mulde 《Cephalalgia : an international journal of headache》1997,17(5):591-595
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan. 相似文献
106.
R. Lazzara A. A. Siddiqui P. Binon S. A. Feldman R. Weiner R. Phillips A. Gonshor 《Clinical oral implants research》1996,7(1):73-83
Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0mm diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration 2.3%crestal bone loss requiring periodontal therapy after the first year of function 1.7% and mechanical problems associated with the prosthesis 0.9%. This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed. 相似文献
107.
本文报道了1984年10月~1985年10月西安市城市居民138例食管癌的病例对照研究。结果表明,吸烟为食管癌发病的危险因素,ORM-H为4.12(95% CI为1.57~6.54)。OR与吸烟量、吸烟年限有显著剂量效应关系。吸烟作为食管癌的可能致病因子其潜隐期为37.19年。饮酒与食管癌的联系不显著(χ2=1.03,P﹥0.05)。作者认为吸烟单独或与其它因素共同作用下可能参与食管的癌变过程。 相似文献
108.
铸造粉尘对接尘工人肺功能影响的配对研究 总被引:3,自引:0,他引:3
按配对设计方法,排除年龄、身高等生理因素与吸烟因素的影响,分析了铸造粉尘对接尘工人肺功能的影响。结果表明:无论是铸钢或铸铁接尘工人,FVC、FEV1.0、FEF25~75、V75、V50等项指标的实测值及实测值占预计值的百分比均较对照组明显降低(P<0.05或P<0.01),肺功能的异常率则显著增高(P<0.05或P<0.01)。 相似文献
109.
房间隔入路的解剖学研究及临床应用 总被引:3,自引:0,他引:3
对33具尸体的房间隔的大小、构成及周围重要组织结构进行观察和测量。提出房间隔切开时的正确方向、安全长度及可能发生的危险。结合466例临床应用,讨论了避免切口合并症发生及发生后的正确处理方法。 相似文献
110.
为探讨孕妇乙型肝炎病毒(HBV)感染和某些因素对先天性畸形的致病作用,本文进行了96对新生儿先天畸形的配对(1:1)病例对照研究,报道先天畸形的频率和构成,单因素和多因素的条件Logistic回归分析,表明孕妇HBsAg阳性等6个因素对先天畸形呈阴性结果,而与接触农药和孕周的因素有明显联系,值得进一步探讨。 相似文献