全文获取类型
收费全文 | 35001篇 |
免费 | 3414篇 |
国内免费 | 1016篇 |
专业分类
耳鼻咽喉 | 322篇 |
儿科学 | 417篇 |
妇产科学 | 388篇 |
基础医学 | 2102篇 |
口腔科学 | 9675篇 |
临床医学 | 2166篇 |
内科学 | 2695篇 |
皮肤病学 | 611篇 |
神经病学 | 631篇 |
特种医学 | 533篇 |
外国民族医学 | 3篇 |
外科学 | 1420篇 |
综合类 | 4195篇 |
现状与发展 | 3篇 |
预防医学 | 2042篇 |
眼科学 | 179篇 |
药学 | 7666篇 |
33篇 | |
中国医学 | 2526篇 |
肿瘤学 | 1824篇 |
出版年
2024年 | 89篇 |
2023年 | 663篇 |
2022年 | 1030篇 |
2021年 | 1411篇 |
2020年 | 1567篇 |
2019年 | 1505篇 |
2018年 | 1384篇 |
2017年 | 1357篇 |
2016年 | 1356篇 |
2015年 | 1390篇 |
2014年 | 2018篇 |
2013年 | 2547篇 |
2012年 | 2020篇 |
2011年 | 2173篇 |
2010年 | 1720篇 |
2009年 | 1439篇 |
2008年 | 1516篇 |
2007年 | 1541篇 |
2006年 | 1392篇 |
2005年 | 1304篇 |
2004年 | 1098篇 |
2003年 | 1012篇 |
2002年 | 864篇 |
2001年 | 742篇 |
2000年 | 661篇 |
1999年 | 520篇 |
1998年 | 470篇 |
1997年 | 523篇 |
1996年 | 385篇 |
1995年 | 338篇 |
1994年 | 340篇 |
1993年 | 252篇 |
1992年 | 294篇 |
1991年 | 280篇 |
1990年 | 238篇 |
1989年 | 230篇 |
1988年 | 204篇 |
1987年 | 184篇 |
1986年 | 159篇 |
1985年 | 200篇 |
1984年 | 201篇 |
1983年 | 159篇 |
1982年 | 134篇 |
1981年 | 110篇 |
1980年 | 80篇 |
1979年 | 63篇 |
1978年 | 51篇 |
1977年 | 68篇 |
1976年 | 46篇 |
1975年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
E. Andrs G. Kaltenbach E. Noel M. Noblet‐Dick A.‐E. Perrin T. Vogel J.‐L. Schlienger M. Berthel J. F. Blickl 《International journal of laboratory hematology》2003,25(3):161-166
Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia. 相似文献
62.
合成了文题所述的十三个手性液晶化合物。经元素分析和红外光谱分析确证了其结构,并进行了相态、相变温度和电滞回线的测定,证实其为铁电液晶。 相似文献
63.
The objective of the present study was to assess possible adaptive functional changes in the masticatory system after insertion of fixed prostheses supported by osseointegrated implants in the edentulous mandible. Registrations of mandibular movement characteristics and maximal biteforce were performed at insertion and after 1 week, 3 months and 1 year after connection. The duration of the opening and closing phase decreased and maximal biteforce increased significantly (p < or = 0.05-0.001) from connection of the prostheses to the annual check-up. However, the process of functional adaptation implied 2 identified stages. An immediate phase that occurred within the 1st week, probably due to altered impact from mechano-sensitive receptors and a later more time-dependent phase, based on learning and new cortical engrams. Accordingly, the process of adaptation will continue over a long period of time. 相似文献
64.
65.
服用左炔诺孕酮滴丸和妈富隆1年对血压、血糖和血脂的影响 总被引:1,自引:0,他引:1
杨玉健 《天津医科大学学报》2003,9(3):373-377
目的:观察第二、三代口服避孕药(COC)对育龄妇女体重指数、血压、血糖和血脂的影响。方法:将自愿服用COC避孕1年的妇女105例随机分为两组,其中54例给予第二代COC(EE/LNG组),51例给予第三代COC(EE/DG组)。并对研究前后所有病例的体重指数(BMI)、血压、血糖和血脂代谢指标进行比较分析。结果:EE/LNG组:BMI、收缩压、舒张压、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)和载脂蛋白B(ApoB)水平均升高,高密度脂蛋白(HDL)水平下降,血糖、载脂蛋白AI(ApoAI)水平无明显改变。EE/DG组收缩压、TG、HDL水平升高,BMI、舒张压、血糖、TC、LDL、ApoAI和ApoB均未发生显著变化。以上所有测量指标均未超出正常范围。结论:使用1年第二、三代COC对妇女BMI、血压和血脂代谢都有微弱的影响,对空腹血糖无明显影响。第三代COC对妇女BMI、收缩压、舒张压、TG、TC、LDL、HDL水平和ApoB的不利影响小于第二代,更加安全可靠。 相似文献
66.
67.
Histoplasmosis is a fungal disease that affects humans and is caused by Histoplasma capsulatum. The presentation of the infection may be acute, chronic, or disseminated. The disseminated form has extrapulmonary manifestations which may include oral manifestation a. A patient with AIDS sought treatment and he had disseminated histoplasmosis with oral manifestations. The purpose of this case report and literature review is to emphasize the role the dental team has in the diagnosis of disseminated disease when a patient presents with oral manifestations associated with the disease. This case report is clinically relevant because it is not uncommon for oral manifestations to be one of the first signs of systemic disease. 相似文献
68.
Stefano Miceli Sopo Daniele Radzik Mauro Calvani 《Pediatric allergy and immunology》2007,18(7):575-582
Investigators have tried to identify a level of seric specific immunoglobulin E (IgE) that had a sufficient predictive value to diagnose a food allergy without having will resort to the food challenge. To search in literature, all the studies that have estimated the possibility to identify a level of seric specific cow milk IgE with a positive predictive value (PPV) of 95% for the first diagnosis of cow's milk allergy (CMA) in pediatric age. We have identified six studies, nearly all studies suffer from relevant methodological bias. Proposed cut-off are all different. The studied pediatric populations were highly selected. Also neglecting the methodological bias of the studies and the great difference of value between the proposed cut-off, it always remains to consider that the pre-test probability of having a CMA between the children enrolled in the six studies included in this review is particularly high. The likelihood ratio helps to transfer the results of a study on a diagnostic test just to our population, and it is more realistic rather than to entrust itself to the PPV or the negative predictive value, that are much influenced from the prevalence of the disease in the studied population. 相似文献
69.
Ø. Lidegaard 《Acta neurologica Scandinavica》1987,75(6):427-433
The mortality of cerebrovascular diseases in Denmark was analysed for men and women 15-44 years of age, in a 14-year period before and after the appearance of oral contraceptives (OC) in 1966. 1,670 deaths were registered over 28 years, during which the female incidence of cerebrovascular deaths increased by 19% (P less than 0.025), while the male mortality was unchanged. Women showed a percentage increase in deaths from cerebral thromboembolic attacks (CTA) of 33%, men a fall of 14%. The increase of female CTA deaths was most pronounced in the young fertile group, the age group with a high OC use. A relative risk of CTA of 3.3-4.5 for OC users compared with non-users could explain the CTA trend difference between women and men. No other single risk factor responsible for the observed trends could be identified. Both women and men had a significant increase in the mortality of subarachnoidal hemorrhages, and a significant fall in the mortality of intracerebral hemorrhages. 相似文献
70.
目的:考察新药依西美坦片在3种不同介质中的溶出特性,以研究影响其口服吸收速率的主要因素和规律。方法:建立HPLC法检测其制剂含量和溶出液浓度,色谱柱:HypersilC18(150mm×4.6mm,5μm);流动相:甲醇:0.05mol/LKH2PO4溶液(60:40);检测波长:247nm。溶出介质选用水、0.1mol/L盐酸溶液及0.5%十二烷基硫酸钠溶液,采用转篮法,转速100r/min。结果:依西美坦片在水和0.1mol/L盐酸溶液中的溶出较差,在0.5%十二烷基硫酸钠溶液巾溶出迅速完全,60min时在3种介质中的溶出百分率分别为(60.25±3.76)%、(47.57±1.20)%和(82.24±0.96)%。结论:依西美坦片可能主要在肠道溶出,其溶出速率受介质影响大。 相似文献