全文获取类型
收费全文 | 13790篇 |
免费 | 154篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 75篇 |
儿科学 | 294篇 |
妇产科学 | 748篇 |
基础医学 | 1809篇 |
口腔科学 | 578篇 |
临床医学 | 1071篇 |
内科学 | 1743篇 |
皮肤病学 | 201篇 |
神经病学 | 1269篇 |
特种医学 | 285篇 |
外科学 | 1030篇 |
综合类 | 414篇 |
预防医学 | 970篇 |
眼科学 | 253篇 |
药学 | 2084篇 |
2篇 | |
中国医学 | 65篇 |
肿瘤学 | 1096篇 |
出版年
2024年 | 66篇 |
2023年 | 831篇 |
2022年 | 578篇 |
2021年 | 918篇 |
2020年 | 1064篇 |
2019年 | 1126篇 |
2018年 | 1164篇 |
2017年 | 786篇 |
2016年 | 572篇 |
2015年 | 519篇 |
2014年 | 1090篇 |
2013年 | 2076篇 |
2012年 | 365篇 |
2011年 | 199篇 |
2010年 | 209篇 |
2009年 | 168篇 |
2008年 | 133篇 |
2007年 | 158篇 |
2006年 | 130篇 |
2005年 | 174篇 |
2004年 | 154篇 |
2003年 | 82篇 |
2002年 | 78篇 |
2001年 | 76篇 |
2000年 | 66篇 |
1999年 | 62篇 |
1998年 | 60篇 |
1997年 | 36篇 |
1996年 | 38篇 |
1995年 | 37篇 |
1994年 | 58篇 |
1993年 | 44篇 |
1992年 | 44篇 |
1991年 | 45篇 |
1990年 | 47篇 |
1989年 | 49篇 |
1988年 | 35篇 |
1987年 | 29篇 |
1986年 | 20篇 |
1985年 | 97篇 |
1984年 | 87篇 |
1983年 | 62篇 |
1982年 | 80篇 |
1981年 | 55篇 |
1980年 | 50篇 |
1979年 | 35篇 |
1978年 | 34篇 |
1977年 | 28篇 |
1976年 | 26篇 |
1974年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Sunil Tomar Varsha Ganesan Ankit Sharma Chang Zeng Lisa Waggoner Andrew Smith Chang H. Kim Paula Licona-Limón Richard L. Reinhardt Richard A. Flavell Yui-Hsi Wang Simon P. Hogan 《The Journal of allergy and clinical immunology》2021,147(1):280-295
- Download : Download high-res image (233KB)
- Download : Download full-size image
102.
J. A. Vega I. Esteban F. J. Naves M. E. Valle L. Malinovsky 《Anatomy and embryology》1995,191(1):33-39
We used immunohistochemical techniques and monoclonal antibodies to localize two basement membrane components (laminin and type IV collagen) in the nerves and sensory nerve formations, or corpuscles, supplying human digital skin. Furthermore, neurofilament proteins, S-100 protein and epithelial membrane antigen were studied in parallel. In dermal nerve trunks, immunostaining for laminin and type IV collagen was found to be co-localized in the perineurium and the Schwann cells, the stronger immunoreactivity being at the external surface of the cells. In the Meissner digital corpuscles, the immunoreactivity for laminin and type IV collagen was mainly observed underlying the cell surface of lamellar cells, while the cytoplasm was weakly immunolabelled or unlabelled. Finally, within Pacinian corpuscles co-localization of the two basement membrane molecules was encountered in the inner core, intermediate layer, outer core and capsule. Laminin and type IV collagen immunoreactivities were also found in blood vessels and sweat glands, apparently labelling basement membrane structures. The present results provide evidence for the presence of basement membrane in all periaxonic cells forming human cutaneous sensory nerve formations, and suggest that all of them are able to synthesize and release some basement membrane components, such as laminin and type IV collagen. The possible role of laminin in sensory nerve formations is discussed. 相似文献
103.
P. V. Sergeev I. M. Romanenko T. V. Ukhina 《Bulletin of experimental biology and medicine》1993,116(3):1104-1106
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N
o
9, pp. 272–274, September, 1993. 相似文献
104.
Normal platelet membranes were exposed in vitro to a variety of psychotropic medications commonly used in the treatment of patients with psychiatric disorders. Changes in structural order at the hydrocarbon region of the drug-exposed membranes were determined by steadystate fluorescence polarization measurements employing the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH). Chlorpromazine, an aliphatic phenothiazine, produced a significant increase in DPH fluorescence polarization at concentrations from 2–200 M. Thioridazine, a piperidine phenothiazine, and three piperazine derivatives, perphenazine, trifluoperazine, and fluphenazine, produced significant increases in this parameter at concentrations from 20–200 M. The other agents tested, including thiothixene, lithium, antidepressants, anxiolytics, and anticonvulsants, were without effect in the concentration ranges examined. The phenothiazine-induced increase in DPH fluoresence polarization apparently depended on the structure of the phenothiazine nucleus; changes in side-chain structure appeared to modulate this effect, most likely by altering the inherent membrane solubility of the agents. 相似文献
105.
Puttemans ML Dryon L Massart DL 《Journal of pharmaceutical and biomedical analysis》1985,3(6):503-510
Synthetic dyes were extracted from syrups, oral suspensions, tablets, gelatin capsules, suppositories and granules by ion-pair formation with tri-n-octylamine (TnOA) and back-extracted with perchlorate ions. Identification was performed by TLC on cellulose layers and by reversed phase ion-pair HPLC. 相似文献
106.
107.
Jan Höltge Linda Theron Richard G. Cowden Kaymarlin Govender Sally I. Maximo Jennifer S. Carranza Bhumika Kapoor Aakanksha Tomar Angelique van Rensburg Shuang Lu Hongwei Hu Valeria Cavioni Alessia Agliati Ilaria Grazzani Yoel Smedema Gunjanpreet Kaur Kingsley G. Hurlington Jackie Sanders Michael Ungar 《The Journal of adolescent health》2021,68(3):580-588
PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources. 相似文献
108.
羊水葡萄糖及白介素-6在胎膜早破中的意义 总被引:1,自引:0,他引:1
目的 探讨胎膜早破患者羊水中葡萄及白介素-6(IL-6)含量与宫内感染的关系。方法 随机选择1994-1999年70例无妊娠并发症的胎膜早破的患者,在B超引导下,经腹行羊膜腔内穿刺,抽取羊水,用葡萄糖氧化酶方法测定水中葡萄糖,用酶联免疫方法测定IL-6含量。结果 胎膜早破并宫内感染者,羊水葡萄糖含量明显下降,IL-6含量则明显增高,当羊水葡萄糖含量≤0.55mmol/L,IL-6含量≥315ng/L时,预测宫内感染的敏感性100%,特异性>80.00%。结论 胎膜早破患者,测定羊水葡萄糖及IL-6含量,能早期快速预测宫内感染。 相似文献
109.
Anna Vassiliou Catherine H. Martin Sheryl T. Homa Jesse Stone Andrew Dawkins Mariya N. Genkova Helen Skyla Dela Roca Sejal Parikh Jinal Patel Tet Yap Aideen P. Killeen 《Andrologia》2021,53(2):e13938
Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOXsys analyser for measuring static oxidation–reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOXsys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOXsys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOXsys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility. 相似文献
110.
Ya-hui Xu Yue Li Su-qin Hu Chun-rui Li Dian-long Liu Ke Hu Li-dan Cui Jian Guo 《Andrologia》2021,53(9):e14169
The blood–testis barrier (BTB) of Sertoli cells (SCs) is an important biological barrier that maintains spermatogenesis and provides a favourable microenvironment for spermatogenesis. However, heat stress can directly damage the BTB structural proteins of testicular SCs, leading to dyszoospermia. Wuzi Yanzong Pills (WYP) is a traditional Chinese medicine formula used to treat male reproductive diseases. However, whether WYP could ameliorate heat stress injury in primary SCs extracted from rat testes and BTB proteins remains unknown. Here, treatment with WYP (low, medium and high dose) increased the SC viability and the proliferation of cell antigen Ki67 significantly. Additionally, it promoted SC maturation, which presented in the form of increased androgen receptors (ARs) and decreased cytokeratin 18 (CK-18) in three WYP dose groups. WYP upregulated BTB proteins such as zonula occludens 1 (ZO-1) and occludin across all WYP groups and decreased phosphorylated Akt (p-Akt) in the middle and high-dose groups; however, ZO-1 and occludin recovery were reduced with the presence of Akt inhibitor in WYP groups. WYP improved SC viability and proliferation, and ameliorated dedifferentiation and BTB-proteins damaged by heat stress via Akt signalling. The findings present theoretical support for the effects of WYP in the management of dyszoospermia and male infertility. 相似文献