全文获取类型
收费全文 | 489篇 |
免费 | 29篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 21篇 |
妇产科学 | 7篇 |
基础医学 | 62篇 |
口腔科学 | 10篇 |
临床医学 | 73篇 |
内科学 | 104篇 |
皮肤病学 | 5篇 |
神经病学 | 30篇 |
特种医学 | 132篇 |
外科学 | 20篇 |
综合类 | 8篇 |
预防医学 | 14篇 |
眼科学 | 4篇 |
药学 | 23篇 |
肿瘤学 | 21篇 |
出版年
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 2篇 |
2014年 | 8篇 |
2013年 | 14篇 |
2012年 | 8篇 |
2011年 | 12篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 3篇 |
2007年 | 16篇 |
2006年 | 7篇 |
2005年 | 13篇 |
2004年 | 7篇 |
2003年 | 7篇 |
2002年 | 10篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 15篇 |
1998年 | 36篇 |
1997年 | 19篇 |
1996年 | 25篇 |
1995年 | 20篇 |
1994年 | 22篇 |
1993年 | 18篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 14篇 |
1989年 | 23篇 |
1988年 | 33篇 |
1987年 | 13篇 |
1986年 | 17篇 |
1985年 | 16篇 |
1984年 | 12篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 4篇 |
1980年 | 11篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 8篇 |
1976年 | 6篇 |
1973年 | 2篇 |
1968年 | 2篇 |
1947年 | 1篇 |
排序方式: 共有536条查询结果,搜索用时 15 毫秒
531.
532.
SL Schor I Ellis CR Irwin J Banyard K Seneviratne C Dolman AD Gilbert DM Chisholm 《Oral diseases》1996,2(2):155-166
Wound healing in the adult is commonly compromised by excessive scar formation. In contrast, fetal wound healing is a regenerative process characterised by the conspicuous absence of scarring. Available evidence suggests that phenotypic differences between fetal and adult fibroblasts are important determinants of these distinct modes of tissue repair. In this context, a number of groups (including our own) have documented differences between fetal and adult fibroblasts with respect to such potentially relevant characteristics as migratory activity, motogenic response to cytokines and the synthesis of motility factors, cytokines and matrix macromolecules. The oral mucosa appears to be a privileged site in the adult in that it continues to display a fetal-like mode of wound healing. Data are presented in this review indicating that a subpopulation of gingival fibroblasts expresses several 'fetal-like' phenotypic characteristics. These observations are discussed in terms of both the continued expression of a fetal-like mode of wound healing in the oral mucosa and the possible differential involvement of distinct fibroblast subpopulations in the progression of periodontal disease. 相似文献
533.
ObjectiveTo investigate the nutritional status of the males and females in two subgroups of the Bhotia tribe (Marcha and Tolcha) inhabiting in three different altitudes in Uttaranchal, India.MethodsData were collected from the Tolcha and Marcha, two sub-groups of the Bhotia, inhabiting in Chamoli district of Uttaranchal. Bhotia adults of both sexes were considered. Field investigation was conducted in three ecological zones (high, middle and low altitude) of the district during April-August, in the years 2002-2004. Anthropometric measurements were obtained in accordance with the techniques recommended by Weiner and Lourie (1981). The variables like height, weight, waist circumference, hip circumference, waist-hip ratio and blood pressure were studied in relation to BMI.ResultsRelatively higher value of mean BMI is recorded among the females than that of the males, which is true for different altitudes, in both subgroups. The BMI also indicates an inverse relationship with altitude, except for the Tolcha males in high altitude. Lowest mean BMI is recorded in middle altitude among the Tolcha subgroup. Chronic energy deficient (CED) individuals are much more than twice the number among the males of both the subgroups inhabiting in different altitudes. Interestingly, the percentage of CED individuals increases with the altitude.ConclusionsRegression analysis indicates that height, weight, hip circumference and waist circumference are dependent on body mass index in the studied populations. Probable reason for poor nutrition status among the Tolcha and Marcha of high altitude might be due to the fact that the Tolcha and Marcha of high altitude consume lesser amount of proteins, fat, milk and milk products in general than their counterpart inhabit in lower and middle altitude. 相似文献
534.
CR de Andrade PF Leite AC Montezano DA Casolari A Yogi RC Tostes R Haddad MN Eberlin FRM Laurindo HP de Souza FMA Corr��a AM de Oliveira 《British journal of pharmacology》2009,157(4):568-580
Background and purpose:
There are interactions between endothelin-1 (ET-1) and endothelial vascular injury in hyperhomocysteinemia (HHcy), but the underlying mechanisms are poorly understood. Here we evaluated the effects of HHcy on the endothelin system in rat carotid arteries.Experimental approach:
Vascular reactivity to ET-1 and ETA and ETB receptor antagonists was assessed in rings of carotid arteries from normal rats and those with HHcy. ETA and ETB receptor expression was assessed by mRNA (RT-PCR), immunohistochemistry and binding of [125I]-ET-1.Key results:
HHcy enhanced ET-1-induced contractions of carotid rings with intact endothelium. Selective antagonism of ETA or ETB receptors produced concentration-dependent rightward displacements of ET-1 concentration response curves. Antagonism of ETA but not of ETB receptors abolished enhancement in HHcy tissues. ETA and ETB receptor gene expressions were not up-regulated. ETA receptor expression in the arterial media was higher in HHcy arteries. Contractions to big ET-1 served as indicators of endothelin-converting enzyme activity, which was decreased by HHcy, without reduction of ET-1 levels. ET-1-induced Rho-kinase activity, calcium release and influx were increased by HHcy. Pre-treatment with indomethacin reversed enhanced responses to ET-1 in HHcy tissues, which were reduced also by a thromboxane A2 receptor antagonist. Induced relaxation was reduced by BQ788, absent in endothelium-denuded arteries and was decreased in HHcy due to reduced bioavailability of NO.Conclusions and implications:
Increased ETA receptor density plays a fundamental role in endothelial injury induced by HHcy. ET-1 activation of ETA receptors in HHcy changed the balance between endothelium-derived relaxing and contracting factors, favouring enhanced contractility.British Journal of Pharmacology (2009) 157, 568–580; doi:10.1111/j.1476-5381.2009.00165.x; published online 9 April 2009This article is part of a themed section on Endothelium in Pharmacology. For a list of all articles in this section see the end of this paper, or visit: http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 相似文献535.
Ladziński P Majchrzak H Kaspera W Maliszewski M Majchrzak K Tymowski M Adamczyk P 《Neurologia i neurochirurgia polska》2012,46(3):205-215
Background and purposeThe partial transcondylar approach (PTA) is an alternative to the suboccipital approach in the surgical treatment of meningiomas of the anterior portion of the craniovertebral junction (APCVJ). The purpose of this study is to present our results of treatment of these meningiomas using PTA.Material and methodsFourteen patients (11 women, 3 men) with meningioma of the APCVJ were included in the study. Neurological status of the patients was assessed before and after surgery as well as at the conclusion of the treatment. The approximate volume of the operated tumour, its relation to large blood vessels, cranial nerves and brainstem, along with its consistency and vascularisation were assessed.ResultsThe symptom duration ranged from 1 to 36 months (median: 11 months). In 79% of patients, motor deficits of the extremities were predominant symptoms. Less frequent symptoms included headache, cervical pain and sensory deficits of cervical nerves C2 to C5. Approximate volume of the tumours ranged from 2.5 mL to 22.1 mL (mean: 11.7 mL). Gross total or subtotal resection was achieved in 86% of patients. The postoperative performance status improved in 57%, did not change in 36% and deteriorated in 7% of the patients.ConclusionsThe PTA is a useful technique for removal of meningiomas expanding intradurally of the APCVJ without significant compression of the medulla. The results of treatment were good in most patients. 相似文献