全文获取类型
收费全文 | 7228篇 |
免费 | 462篇 |
国内免费 | 168篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 29篇 |
妇产科学 | 7篇 |
基础医学 | 433篇 |
口腔科学 | 1767篇 |
临床医学 | 804篇 |
内科学 | 1255篇 |
皮肤病学 | 129篇 |
神经病学 | 785篇 |
特种医学 | 289篇 |
外科学 | 225篇 |
综合类 | 988篇 |
现状与发展 | 2篇 |
一般理论 | 4篇 |
预防医学 | 334篇 |
眼科学 | 49篇 |
药学 | 393篇 |
6篇 | |
中国医学 | 306篇 |
肿瘤学 | 39篇 |
出版年
2024年 | 81篇 |
2023年 | 155篇 |
2022年 | 302篇 |
2021年 | 367篇 |
2020年 | 313篇 |
2019年 | 296篇 |
2018年 | 274篇 |
2017年 | 272篇 |
2016年 | 247篇 |
2015年 | 221篇 |
2014年 | 460篇 |
2013年 | 466篇 |
2012年 | 357篇 |
2011年 | 345篇 |
2010年 | 299篇 |
2009年 | 254篇 |
2008年 | 297篇 |
2007年 | 291篇 |
2006年 | 253篇 |
2005年 | 211篇 |
2004年 | 173篇 |
2003年 | 170篇 |
2002年 | 128篇 |
2001年 | 164篇 |
2000年 | 99篇 |
1999年 | 69篇 |
1998年 | 102篇 |
1997年 | 78篇 |
1996年 | 77篇 |
1995年 | 77篇 |
1994年 | 66篇 |
1993年 | 69篇 |
1992年 | 98篇 |
1991年 | 73篇 |
1990年 | 66篇 |
1989年 | 53篇 |
1988年 | 54篇 |
1987年 | 52篇 |
1986年 | 56篇 |
1985年 | 50篇 |
1984年 | 46篇 |
1983年 | 47篇 |
1982年 | 45篇 |
1981年 | 32篇 |
1980年 | 35篇 |
1979年 | 19篇 |
1978年 | 15篇 |
1977年 | 22篇 |
1976年 | 17篇 |
1975年 | 24篇 |
排序方式: 共有7858条查询结果,搜索用时 15 毫秒
141.
Claydon N Leach K Newcombe RG Ley F Scratcher C Addy M 《Journal of clinical periodontology》2000,27(10):749-752
BACKGROUND: Toothbrush filament configuration now varies considerably, usually with the intention of improving plaque removal overall or from specific sites. AIMS: The aim of the study was to compare 2 branded toothbrushes with a brush designed with a convex filament head arrangement to improve plaque removal from teeth with buccal gingival recession. METHODS: The study was a randomised, 3-treatment, double-blind crossover design balanced for residual effects and involving 18 healthy volunteers. On day 1, subjects suspended toothcleaning and returned to the clinic on day 4. Plaque was scored by area and index before and after 2 min of toothbrushing with the allocated brush. Brushing was performed by a hygienist allocating a timed 15 s to each of the 8 buccal and lingual quadrants. 3 days was allowed between treatment periods. RESULTS: Plaque accumulation differed considerably by site as did plaque removal. Overall plaque removal was 40%. Analysis showed significant subject differences but, no significant period or treatment differences. CONCLUSIONS: Consistent with other reports, it must be concluded that brush design is not a major variable in plaque removal. However using this "robot"-like model, the dentition of some individuals and specific dental surfaces are inherently more difficult to clean than others. 相似文献
142.
143.
van de Kerkhof PC Berth-Jones J Griffiths CE Harrison PV Hönigsmann H Marks R Roelandts R Schöpf E Trompke C 《The British journal of dermatology》2002,146(3):414-422
BACKGROUND: As psoriasis patients often require continuous treatment optimal therapy has to provide efficacy and a good safety profile over the long term. OBJECTIVES: The aim of this multicentre study was to assess the efficacy, safety and tolerability of tacalcitol (4 microg g(-1)) ointment (Curatoderm, Hermal, Reinbek, Germany) applied once daily over a treatment period of 18 months. PATIENTS AND METHODS: Efficacy parameters were Psoriasis Area Severity Index (PASI), based on summed scores of erythema, infiltration and scaling and total body surface involvement (TBI). Safety assessment included serum levels of calcium, parathyroid hormone, calcitonin, 1,25-dihydroxy vitamin D3 (calcitriol); urinary calcium, creatinine, calcium/creatinine ratio in spot and 24-h urine and urinary alpha(1)-microglobulin. A group of 304 patients with chronic plaque psoriasis, covering between 7% and 20% of the body surface area was included for the initial treatment phase of 3 months. Of the 257 patients who completed the initial 3 months, 197 patients continued in a second treatment phase of 15 months. RESULTS: Tacalcitol treatment proved to be effective in reducing the severity of psoriasis and maintained therapeutic response over the study period. The median PASI fell from 9.5 to 4 .6 at month 3 and to 3.25 at month 18 (P < 0.0001). The median improvement in TBI was 30% at month 3 and 50% at month 18. In no patient was there any relevant disturbance of calcium homeostasis. There were no significant changes in mean values of serum calcium, parathyroid hormone and calcitriol. Additionally no significant changes in 24-h urinary excretion evaluation were observed. There was no correlation between levels of serum calcium or urinary calcium and amount of tacalcitol ointment used, even in the patients requiring the largest amounts of ointment (up to 13 g day(-1) and up to 20% of body area affected). Treatment was generally well tolerated and there were no serious or unexpected adverse events reported. However, discontinuation of treatment as a result of skin irritation was seen in 5.9% of patients. The greatest frequency of cutaneous side-effects occurred during initial treatment and the incidence decreased markedly as the treatment was well-tolerated with continued use. CONCLUSIONS: Tacalcitol ointment once daily was demonstrated to be efficacious, safe and well tolerated in the long-term control of plaque psoriasis in patients with up to 20% body surface involvement. 相似文献
144.
145.
146.
147.
148.
Atherosclerotic cardiovascular disease is extremely common in older adults and the potential benefits of secondary prevention are perhaps greater in this population than in younger patients. While there is good evidence that secondary prevention efforts are justified in patients up to 80 years of age, limited data are available on secondary prevention in octogenarians and there is no evidence to guide treatment in patients ≥ 90 years of age. Further, the value of secondary prevention may be confounded by prevalent comorbidities, polypharmacy, and limited life expectancy. It is therefore essential that all management decisions be made in relation to individual preferences and goals of care, with understanding by patients that benefits as well as risks may increase with age. Furthermore, research is needed to refine markers to better delineate which older adults are most likely to benefit from preventive therapies. 相似文献
149.
冠状动脉粥样硬化斑块破裂的临床危险因素分析 总被引:10,自引:0,他引:10
目的 研究临床危险因素与冠状动脉粥样硬化斑块破裂的关系 ,探讨斑块破裂的危险因素。方法 选取 1992~ 1998年间的尸检病例 ,急性心肌梗死 (AMI) 2 0例 ,不稳定心绞痛 (UA) 10例 ,稳定心绞痛 (SA) 12例 ,对所有冠状动脉连续取材制片 ,常规及免疫组化染色 ,光镜观察斑块破裂的形态改变及血栓伴随情况 ,并调查 8个相应的临床危险因素。结果 8个危险因素中 ,血浆甘油三酯水平与斑块破裂有关 (P <0 .0 5 )。结论 高血浆甘油三酯是国人急性冠状动脉综合征患者斑块破裂的一个重要危险因素。 相似文献
150.