全文获取类型
收费全文 | 1103篇 |
免费 | 72篇 |
国内免费 | 4篇 |
专业分类
儿科学 | 27篇 |
妇产科学 | 38篇 |
基础医学 | 186篇 |
口腔科学 | 16篇 |
临床医学 | 91篇 |
内科学 | 290篇 |
皮肤病学 | 52篇 |
神经病学 | 106篇 |
特种医学 | 36篇 |
外科学 | 71篇 |
综合类 | 7篇 |
预防医学 | 79篇 |
眼科学 | 8篇 |
药学 | 96篇 |
中国医学 | 8篇 |
肿瘤学 | 68篇 |
出版年
2023年 | 14篇 |
2022年 | 30篇 |
2021年 | 35篇 |
2020年 | 25篇 |
2019年 | 23篇 |
2018年 | 42篇 |
2017年 | 21篇 |
2016年 | 21篇 |
2015年 | 37篇 |
2014年 | 38篇 |
2013年 | 45篇 |
2012年 | 103篇 |
2011年 | 111篇 |
2010年 | 54篇 |
2009年 | 50篇 |
2008年 | 71篇 |
2007年 | 73篇 |
2006年 | 60篇 |
2005年 | 57篇 |
2004年 | 74篇 |
2003年 | 64篇 |
2002年 | 54篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1982年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1968年 | 3篇 |
1967年 | 1篇 |
1966年 | 2篇 |
1963年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有1179条查询结果,搜索用时 15 毫秒
1.
Filomena Napolitano Valentina Di Iorio Giuseppe Di Iorio Mariarosa Anna Beatrice Melone Fernando Gianfrancesco Francesca Simonelli 《Ophthalmic genetics》2019,40(1):39-42
Background: Extracellular matrix molecular components, previously linked to multisystem syndromes include collagens, fibrillins and laminins. Recently, we described a novel multisystem syndrome caused by the c.9418G>A p.(V3140M) mutation in the laminin alpha-5 (LAMA5) gene, which affects connective tissues of all organs and apparatus in a three generation family. In the same family, we have also reported a myopic trait, which, however, was linked to the Prolyl 4-hydroxylase subunit alpha-2 (P4HA2) gene. Results of investigation on vitreous changes and their pathogenesis are reported in the present study.Materials and Methods: Nineteen family individuals underwent complete ophthalmic examination including best-corrected visual acuity (BCVA), fundus examination, fundus photography, intraocular pressure measurement, axial length measurement using ocular biometry, Goldmann visual field examination, standard electroretinogram, SD-OCT. Segregation analysis of LAMA5 and P4HA2 mutations was performed in enrolled members.Results: The vitreous alterations fully segregated with LAMA5 mutation in both young and adult family members. Slight reduction of retinal thickness and peripheral retinal degeneration in only two patients were reported.Conclusions: In this work we showed that PVD is a common trait of LAMA5 multisystem syndrome, therefore occurring as an age-unrelated trait. We hypothesize that the p.(V3140M) mutation results in a reduction of retinal inner limiting membrane (ILM) stability, leading to a derangement in the macromolecular structure of the vitreous gel, and PVD. Further investigations will be necessary to elucidate the role of wild type and mutated LAMA5 in the pathogenesis of PVD. 相似文献
2.
3.
Nuno Fonseca Filomena Caetano José Santos Filipe Seixo Leonel Bernardino Isabel Silvestre Paula Cardoso Filomena Segurado Lopes Inês 《Revista portuguesa de cardiologia》2004,23(3):365-375
INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function. 相似文献
4.
T Germann F Mattner A Partenheimer E Schmitt A B Reske-Kunz H G Fischer E Rüde 《International immunology》1992,4(7):755-764
The ability of macrophages to stimulate immune responses is heterogeneous and may have influence on the type of the developing immune response. Therefore, in an attempt to define different functional states of mouse macrophages, we made use of the two macrophage growth factors: macrophage colony stimulating factor (M-CSF) and granulocyte macrophage colony stimulating factor (GM-CSF). Generation of macrophages from freshly isolated bone marrow cells in the presence of GM-CSF results in a population expressing profound antigen presenting function for mouse TH1 cells, resulting in strong lymphokine production and proliferation of the T cells. Furthermore, high amounts of a novel soluble cytokine active on mouse TH1 cells are generated during the interaction of TH1 cells with macrophages elicited with GM-CSF. In contrast, macrophages grown from bone marrow cells for at least 14 days in the presence of M-CSF express only minimal antigen-presenting function for TH1 cells. Treatment of such macrophages for 24 h with either IFN-gamma or GM-CSF allows the distinction between two further functional states. Those treated with IFN-gamma efficiently presented antigen towards TH1 cells. The T cells produced large amounts of lymphokines and proliferate well. However, synthesis of the novel soluble cytokine (active on TH1 cells) was not detectable. The generation of this mediator requires a short-term treatment with GM-CSF of macrophages developed in the presence of M-CSF prior to their interaction with TH1 cells. 相似文献
5.
F. Mattner D. Sohr A. Heim P. Gastmeier H. Vennema M. Koopmans 《Clinical microbiology and infection》2006,12(1):69-74
Norovirus infections have been described as self-limiting diseases of short duration. An investigation of a norovirus outbreak in a university hospital provided evidence for severe clinical features in patients with several underlying diseases. Clinical outcomes of norovirus infection were defined. Risk-factor analysis targeting underlying diseases and medication was performed using multivariate analyses. In five outbreak wards, 84 patients and 60 nurses were infected (an overall attack rate of 32% in patients, and 76% in nurses). The causative agent was the new variant Grimsby virus. Severe clinical features, including acute renal failure, arrhythmia and signs of acute graft organ rejection in renal transplant patients, were observed in seven (8.3%) patients. In multivariate analyses, cardiovascular disease (OR 17.1, 95% CI 2.17-403) and renal transplant (OR 13.0, 95% CI 1.63-281) were risk-factors for a potassium decrease of >20%. Age >65 years (OR 11.6, 95% CI 1.89-224) was a risk-factor for diarrhoea lasting >2 days. Immunosuppression (OR 5.7, 95% CI 1.78-20.1) was a risk-factor for a creatinine increase of >10%. Norovirus infections in patients with underlying conditions such as cardiovascular disease, renal transplant and immunosuppressive therapy may lead to severe consequences typified by decreased potassium levels, increased levels of C-reactive protein and creatine phosphokinase. In the elderly, norovirus infection may lead to an increased duration of diarrhoea. Therefore patients at risk should be hospitalised early and monitored frequently. Strict preventional measures should be implemented as early as possible to minimise the risk of nosocomial outbreaks. 相似文献
6.
Tieno Germann Maurice K. Gately David S. Schoenhaut Michael Lohoff Frank Mattner Susanne Fischer Shen-Chu Jin Edgar Schmitt Erwin Rüde 《European journal of immunology》1993,23(8):1762-1770
At least two subsets of CD4+ T helper cell lymphocytes termed Th1 and T h, 2 exist in the mouse and probably in humans. They are characterized by the secretion of different lymphokines and by their functional behavior. Dysregulated expansion of one or the other subset may be one reason for the development of certain diseases. Thus, it is of importance to define the signals involved in the differentiation and activation of the two Th cell subsets. It is known and has been confirmed in this report that the cytokine interleukin (IL)-1 acts onTh2 cells but not on Th1 cells. We now report that a previously identified cytokine which was provisionally termed T cell stimulating factor is identical with IL-12 and exhibits a reciprocal behaviour to IL-1. IL-12 has several effects on Th1 cells. It can induce the proliferation of certain Th1 cells in combination with IL-2. Synthesis of interferon (IFN)-γ by Th1 cells can be triggered by IL-2 plus IL-12. In contrast to the IFN-γ production observed after T cell receptor (TcR) CD3 stimulation of Th1 cells with lectin Concanavalin A the IFN-γ production induced by IL-12+IL-2 is insensitive to the immunosuppressive drug cyclosporin A. Furthermore, IL-12 enhances the TcR/CD3-induced synthesis of IFN-γ of several Th1 clones. Finally, IL-12 (+ IL-2) induces homotypic cell aggregation of Th1 clones. This type of cell aggregation depends on the participation of LFA-1 and ICAM-1 molecules. In all activation systems with Th1 cells no effect of IL-1 was demonstrable. In contrast, only IL-1 but not IL-12 served as a co-stimulatory signal for several Th2 cell lines activated via the TcR/CD3 complex. 相似文献
7.
Experimental research has recently shown that acupuncture induces the formation of o-pioid-like peptides in animals.The role ofβ-endorphin in the mechanism of acupuncture is discussed:some authors maintain the hormonal hypothesis,others the role of neurotransmltters and,up to thepresent,no convincing evidence for either hypothesis has been demonstrated.In order to provide fur-ther evidence,we tested the β-endorphin levels and other parameters(VLP,lymphocyte subsets,NKcells and phagocyte activity of monocytes)in a group of 90 patients suffering from various painful dis-orders treated with acupuncture.Zusanli(ST 36)and Hegu(LI 4)acupoints were selected.A homo-geneous group of 30 subjects was used as control.Evaluation of the above parameters was made with3 series of blood tests;before treatment,30 minutes and 24 hours after acupuncture treatment.In theacupuncture group,the following results were achieved: a)A considerable increase in β-endorphin levels,which remained high even 24 hours afteracup 相似文献
8.
9.
Rui Caetano-Oliveira Marcos António Gomes Ana Margarida Abrantes Edgar Tavares-Silva Marco Carvalho Oliveira Mafalda Laranjo Débora Basílio Queirós João Casalta-Lopes Salomé Pires Lina Carvalho Rosa Gouveia Paulo Rodrigues Santos Denise Gonçalves Priolli José Guilherme Tralhão Maria Filomena Botelho 《Pathophysiology》2018,25(2):89-99
Colorectal cancer (CRC) is the second most frequent and fatal cancer in Western countries. Understanding its biology with different incidence along the colon and rectum, genetic profile and how these factors contribute to local/distant progression, has been hampered by the lack of a suitable CRC model.We report a reproducible model, using human CRC cell lines (CL) (WiDr, LS1034, C2BBe1) injected (1?×?107 cells/animal) in RNU rats (n?=?55) which underwent cecostomy and descending colostomy with mucosal-cutaneous fistula of the sigmoid colon. CL were characterized by immunohistochemistry: CK20, CDX2, P53, vimentin, Ki67, CD44, CD133, E-cadherin, β-catenin and CEA; cancer stem cells-immune system interaction was studied and tumor progression was assessed with nuclear medicine imaging (99mTc-MIBI).Animals developed locally invasive tumors and with WiDr neural invasion was registered. Cancer stem cells were detected in WiDr (CD44 positive). All the cell lines stimulated the immune system, being WiDr the most aggressive. Imaging studies demonstrated tumor uptake.With this CRC model we can study the microenvironment role and tumor-stroma interactions. All CL developed primary disease, but only the WiDR established neural invasion which may represent a metastatic pathway. This model can help unveiling the underlying metastatic mechanisms, and ultimately test better therapeutic approaches for CRC. 相似文献
10.