全文获取类型
收费全文 | 309篇 |
免费 | 14篇 |
国内免费 | 3篇 |
专业分类
儿科学 | 8篇 |
妇产科学 | 10篇 |
基础医学 | 39篇 |
口腔科学 | 5篇 |
临床医学 | 26篇 |
内科学 | 45篇 |
皮肤病学 | 6篇 |
神经病学 | 44篇 |
特种医学 | 4篇 |
外科学 | 34篇 |
综合类 | 2篇 |
预防医学 | 43篇 |
眼科学 | 9篇 |
药学 | 29篇 |
中国医学 | 1篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 3篇 |
2022年 | 9篇 |
2021年 | 13篇 |
2020年 | 4篇 |
2019年 | 9篇 |
2018年 | 7篇 |
2017年 | 15篇 |
2016年 | 7篇 |
2015年 | 12篇 |
2014年 | 10篇 |
2013年 | 17篇 |
2012年 | 18篇 |
2011年 | 28篇 |
2010年 | 9篇 |
2009年 | 8篇 |
2008年 | 18篇 |
2007年 | 16篇 |
2006年 | 22篇 |
2005年 | 13篇 |
2004年 | 12篇 |
2003年 | 21篇 |
2002年 | 13篇 |
2001年 | 2篇 |
1998年 | 2篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1968年 | 6篇 |
1967年 | 2篇 |
排序方式: 共有326条查询结果,搜索用时 15 毫秒
81.
82.
83.
This paper examines comprehensive data on arrests for HIV-specific crimes within a single jurisdiction, the Nashville Tennessee prosecutorial region, over 11 years. There were 25 arrests for HIV exposure and 27 for aggravated prostitution. Eleven of the arrests for HIV exposure involved nonsexual behaviors; none alleged transmission. Sixteen of the arrests for HIV exposure involved sexual behavior; three alleged transmission. Aggravated prostitution cases (i.e. prostitution while knowing one has HIV) often involved solicitation of oral sex; none alleged transmission. Maximum sentences for HIV-specific crimes ranged from 5 to 8 years. We conclude that enforcement of US HIV-specific laws is underestimated. Fifty-two arrests over 11 years were recorded in one jurisdiction. Over half of the arrests involved behaviors posing minimal or no HIV transmission risk. Despite concerns about malicious, intentional HIV transmission, no cases alleged malice or intention. 相似文献
84.
Grozio A Catassi A Cavalieri Z Paleari L Cesario A Russo P 《Anti-cancer agents in medicinal chemistry》2007,7(4):461-466
The respiratory epithelium expresses the cholinergic system including nicotinic receptors (nAChRs). It was reported that normal human bronchial epithelial cells (BEC), which are the precursor for squamous cell carcinomas, and small airway epithelial cells (SAEC), which are the precursor for adenocarcinomas, have slightly different repertoires of nAChRs. Studies shown that nAChRs expressed on lung carcinoma or mesothelioma form a part of an autocrine-proliferative network facilitating the growth of neoplastic cells; others demonstrated that nicotine can promote the growth of colon, gastric, and lung cancers. Nicotine and structurally related carcinogens like NNK [4-(methylnitrosoamino)- 1-(3-pyridyl)-1-butanone] and NNN (N'-nitrosonornicotine) could induce the proliferation of a variety of small cell lung carcinoma cell lines and endothelial cells and nicotine in non-neuronal tissues -including lung- induces the secretion of growth factors (bFGF, TGF-alpha, VEGF and PDGF), up regulation of the calpain family proteins, COX-2 and VEGFR-2, causing the eventual activation of Raf/MAPK kinase/ERK (Raf/MEK/ERK) pathway contributing to the growth and progression of tumors exposed to nicotine through tobacco smoke or cigarette substitutes. It has been demonstrated that nicotine promotes the growth of solid tumors in vivo, suggesting that might induce the progression of tumors already initiated. While tobacco carcinogens can initiate and promote tumorigenesis, the exposure to nicotine could confer a proliferative advantage to early tumors but there is no evidence that nicotine itself provokes cancer. This is supported by the findings that nicotine can prevent apoptosis induced by various agents - such as chemotherapeutic in NSCLC, conferring a survival advantage as well. 相似文献
85.
Adaptive immune responses are orchestrated by specialized professional antigen-presenting cells (APCs), the dendritic cells (DCs), which play crucial roles as initiators and modulators of adaptive immune responses. A main feature of DCs is their phenotypic and functional plasticity. In the absence of any inflammation or pathogenic elements, most DCs in peripheral tissues and lymphoid organs have a resting, immature phenotype characterized by high endocytic capacity and low surface expression of MHC- and costimulatory molecules. However, upon interaction with microbial ligands, pro-inflammatory cytokines or CD40Ligand, DCs rapidly acquire an activated phenotype. These mature DCs have a very efficient T cell-priming ability as a consequence of upregulation of MHC- and costimulatory molecules on their cell surface. For this reason, DC-based vaccines have been used successfully to combat infections and malignancies. Nonetheless, evidence is accumulating that, especially immature, or semi-matured, DCs also have a potent ability to tolerize T cells or prevent undesired immune reactions. Therefore, current and prospective strategies to promote the inherent tolerogenic potential of DCs are a rational approach for the therapy of autoimmune diseases such as rheumatoid arthritis (RA). This review summarizes some aspects of the intriguing ability of DCs to steer the outcome of immunity and their potency to modulate the outcome of various pathological conditions. 相似文献
86.
Cor triatriatum is defined as a membrane within the left atrium, which might lead to restricted pulmonary venous return. Diagnosis is usually achieved by echocardiography, therapy of choice is excision of the membrane. Upon ten new cases, the association with other congenital heart diseases (CHDs), clinical symptoms and the surgical approach are discussed. Eight of ten patients were children, six of them aged<1 year. Additional CHDs included atrial and ventricular septal defects, partial anomalous pulmonary venous return and complex CHD. Surgery was performed in all cases. Prognosis is related to associated CHD. 相似文献
87.
It is well established that last-order premotor interneurons in the spinal cord have crucial importance in the integration of activities generated by the spinal motor apparatus, sensory information and volleys arising from higher motor centers, indicating that they play a substantial role in spinal motor functions. Despite extensive studies, synaptic input systems of these neurons have not been investigated in detail up to now with morphological approaches. On this basis, the present experiments were aimed at the visualization of possible contacts between primary afferents and last-order premotor interneurons in the lumbar spinal cord of rats using double label neural tracing methods in light microscopy. The findings show that terminal puncta of primary afferents do establish indeed appositions on last-order premotor interneurons. From the quantitative point of view, these appositions occur, however, in limited numbers. The study also shows that last-order premotor interneurons contacted by primary afferents tend to be concentrated at the segmental level of the innervated motoneurons, and are evenly distributed along the mediolateral extent of laminae V-VI and in the dorsal portion of lamina VII. 相似文献
88.
89.
Peter Gaal Zita Velkey Viktoria Szerencses Erin Webb 《Health policy (Amsterdam, Netherlands)》2021,125(7):833-840
Hungary, like many countries, features a complex mix of the public and private sector in the financing and provision of health care services. At the same time, the health system also faces challenges related to shortages of health professionals, low public financing, and informal payments. With the added pressure from the COVID-19 pandemic, Hungarian policymakers acted rapidly to pass a sweeping regulation aimed at these issues. Over two days, the Hungarian parliament introduced and unanimously approved a new regulation, Act C of 2020 on the Employment Status of Health Workers, that replaces the existing public employment relationship between health professionals, public providers and their controlling authorities. The Act, passed on 6 October 2020, brings the employment of health workers under strict central control by introducing a new employment status similar to that of the armed forces. The Act also provides doctors with an unprecedented 120% salary increase and criminalizes informal payments. The reception has been overwhelmingly negative, with thousands of health professionals indicating that they would not sign the new contracts, and the policy also contains serious technical and feasibility concerns. Although the first statistics show that only about 3-5% of the active workforce did not sign the contract by 1 March 2021, the implementation of the reform still faces serious challenges. 相似文献
90.