全文获取类型
收费全文 | 11621篇 |
免费 | 714篇 |
国内免费 | 257篇 |
专业分类
耳鼻咽喉 | 237篇 |
儿科学 | 234篇 |
妇产科学 | 352篇 |
基础医学 | 1640篇 |
口腔科学 | 161篇 |
临床医学 | 1181篇 |
内科学 | 2714篇 |
皮肤病学 | 175篇 |
神经病学 | 1070篇 |
特种医学 | 270篇 |
外国民族医学 | 1篇 |
外科学 | 1286篇 |
综合类 | 488篇 |
一般理论 | 3篇 |
预防医学 | 619篇 |
眼科学 | 214篇 |
药学 | 1061篇 |
5篇 | |
中国医学 | 139篇 |
肿瘤学 | 742篇 |
出版年
2024年 | 14篇 |
2023年 | 87篇 |
2022年 | 242篇 |
2021年 | 470篇 |
2020年 | 224篇 |
2019年 | 288篇 |
2018年 | 373篇 |
2017年 | 273篇 |
2016年 | 323篇 |
2015年 | 379篇 |
2014年 | 505篇 |
2013年 | 607篇 |
2012年 | 882篇 |
2011年 | 976篇 |
2010年 | 562篇 |
2009年 | 402篇 |
2008年 | 595篇 |
2007年 | 673篇 |
2006年 | 690篇 |
2005年 | 640篇 |
2004年 | 577篇 |
2003年 | 563篇 |
2002年 | 496篇 |
2001年 | 175篇 |
2000年 | 136篇 |
1999年 | 180篇 |
1998年 | 107篇 |
1997年 | 113篇 |
1996年 | 101篇 |
1995年 | 52篇 |
1994年 | 55篇 |
1993年 | 47篇 |
1992年 | 69篇 |
1991年 | 60篇 |
1990年 | 63篇 |
1989年 | 58篇 |
1988年 | 49篇 |
1987年 | 32篇 |
1986年 | 33篇 |
1985年 | 26篇 |
1984年 | 33篇 |
1983年 | 29篇 |
1982年 | 27篇 |
1981年 | 28篇 |
1980年 | 17篇 |
1979年 | 21篇 |
1978年 | 20篇 |
1977年 | 21篇 |
1975年 | 17篇 |
1973年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll‐like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA‐binding activity of NF‐κB p50 and p65. We found substantial differences in the LPS‐stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL‐16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL‐6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes. 相似文献
5.
Karasu Buğra Gunay Betul Onal 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(1):99-106
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and visual outcomes following different... 相似文献
6.
目的阐明CDFI对评价胎儿宫内状况的可行性。方法200例经普通B超检查的胎儿,按测量各项常规指标的数值分为正常组100例和异常组100例,再分析经CDFI检查,所测定的指标包括胎儿大脑中动脉、肾动脉、胎盘床动脉、脐动脉血流搏动指数(PI)、阻力指数(RI)及脐动脉的收缩与舒张期峰值速率之比(S/D)。对其结果做详细记录,并进行统计学分析。结果正常组100例,经CDFI检查亦正常;胎儿出生时体重在2500g以上,新生儿发育正常。另100例异常组经CDFI检查各项指标中,54例正常,46例异常;胎儿出生时体重均小于2500g,其中54例新生儿虽体重较正常儿偏小,但发育正常;另46例胎儿宫内窘迫,导致导常分娩、新生儿生存率低。结论彩色多普勒血流显像对了解胎儿宫内情况有着重要的作用,是产科检查监护中不可缺少的部分。 相似文献
7.
胰岛素使用方法的研究进展 总被引:11,自引:0,他引:11
胰岛素治疗是糖尿病治疗的重要内容,也是使糖尿病患者血糖达标的有效方法。严格的血糖控制对糖尿病慢性并发症的预防和延缓发生有重要意义,然而目前各国的糖尿病血糖控制达标率均不足50%。患者甚至包括医生对低血糖的恐惧是启动胰岛素治疗和达到最佳胰岛素治疗的主要障碍之一。 相似文献
8.
Micha? Panasiuk Marek Synder Maryla Drynkowska-Panasiuk Oktawiusz Bończak 《Chirurgia narzadów ruchu i ortopedia polska》2006,71(4):265-267
Serum levels of bone markers N-mid osteocalcin (OCN-Mid) and Cross-Laps in 20 patients (8 men and 12 women) with loosening of at least one element of total hip endoprosthesis confirmed during operation were compared with age and sex matched group with OA. Marker levels were measured by direct chemoluminescency using Modular E-170. Statistical analysis were done with t-Student test (alpha = 0.05). There were no significant differences in OCN-Mid, Cross-Laps levels and OCN-Mid/Cross-Laps ratio between both groups. Implant loosening is a slow process taking place on a relatively small surface in comparison to whole skeleton, so bone markers have no clinical value in diagnostics of total hip loosening. 相似文献
9.
Onur Hapa Hüsamettin ?ak?c? Kaan Gidero?lu Kutay ?zturan Aysel Kükner Güler Bu?dayc? 《Archives of orthopaedic and trauma surgery》2009,129(12):1721-1726
Introduction
Ethanol has a suppressive effect on inflammation and the immune system, but the effect of ethanol on tendon healing in vivo has not been studied. The purpose of this study was to investigate the histological and biomechanical effects of ethanol intake on tendon healing in a rat tendon injury model. 相似文献10.
Anna Krygowska-Wajs William P. Cheshire Zbigniew K. Wszolek Alicja Hubalewska-Dydejczyk Barbara Jasinska-Myga Matthew J. Farrer Marek Moskala Anna Sowa-Staszczak 《Parkinsonism & related disorders》2009,15(9):692-696
ObjectiveTo assess for the presence of gastric dysmotility in familial and sporadic Parkinson disease (PD).Methods10 subjects with familial Parkinson disease (fPD), 35 subjects with sporadic Parkinson disease (sPD), and 15 controls, all from academic tertiary care movement disorders centers, were studied. fPD was defined as the presence of at least 2 affected individuals within 2–3 consecutive generations in a family. Molecular genetic analysis has not revealed, thus far, any known genomic abnormality in these families. Gastric emptying was assessed by dynamic abdominal scintigraphy over 92 min following ingestion of a solid meal containing 99mTc-labeled colloid of 40 MBq activity. The main outcome measures were gastric emptying half-time and radiotracer activity over the gastric area at 46 and at 92 min.ResultsGastric emptying time was delayed in 60% of subjects with PD. In comparison to mean t1/2 of 38 ± 7 min in controls, mean t1/2 was 58 ± 25 min in fPD (p = 0.02) and 46 ± 25 min in sPD (p = 0.10). Both fPD and sPD groups included subjects with delayed gastric emptying at an early stage of disease.ConclusionsPatients with fPD showed significantly delayed gastric emptying in comparison to normal age-matched individuals. Further studies of gastrointestinal dysfunction in PD, particularly fPD, are warranted. 相似文献