全文获取类型
收费全文 | 412篇 |
免费 | 17篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 2篇 |
妇产科学 | 2篇 |
基础医学 | 36篇 |
口腔科学 | 2篇 |
临床医学 | 40篇 |
内科学 | 105篇 |
皮肤病学 | 1篇 |
神经病学 | 30篇 |
特种医学 | 5篇 |
外科学 | 88篇 |
综合类 | 6篇 |
预防医学 | 23篇 |
眼科学 | 17篇 |
药学 | 20篇 |
肿瘤学 | 58篇 |
出版年
2023年 | 6篇 |
2022年 | 22篇 |
2021年 | 26篇 |
2020年 | 13篇 |
2019年 | 16篇 |
2018年 | 14篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 17篇 |
2014年 | 20篇 |
2013年 | 37篇 |
2012年 | 40篇 |
2011年 | 48篇 |
2010年 | 18篇 |
2009年 | 14篇 |
2008年 | 22篇 |
2007年 | 24篇 |
2006年 | 13篇 |
2005年 | 16篇 |
2004年 | 15篇 |
2003年 | 12篇 |
2002年 | 10篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有437条查询结果,搜索用时 31 毫秒
421.
Larrauri A Savulescu C Jiménez-Jorge S Pérez-Breña P Pozo F Casas I Ledesma J de Mateo S;Spanish Influenza Surveillance System 《Gaceta sanitaria / S.E.S.P.A.S》2011,25(1):23-28
Introduction
The Spanish influenza surveillance system (SISS) maintained its activity during the summer of 2009 to monitor the influenza pandemic.Objectives
To describe pandemic influenza activity from May to September 2009 and to estimate the effectiveness of the 2008-9 seasonal influenza vaccine against laboratory-confirmed pandemic (H1N1) 2009 influenza.Methods
Data from the SISS were used to identify the trend of pandemic (H1N1) 2009 influenza outside the influenza season. For the effectiveness study, we compared the vaccination status of notified cases [influenza-like illnesses (ILI) laboratory confirmed as pandemic influenza] with that of the test-negative controls.Results
The first laboratory-confirmed case of the pandemic virus was notified in the system in week 20/2009. The ILI rate increased gradually in the study period, exceeding basic activity in week 38. The proportion of pandemic (H1N1) 2009 influenza viruses detected by the system represented 14% in week 20/2009 and rapidly increased to 90% in week 34. The adjusted vaccine effectiveness of the 2008-9 seasonal vaccine against laboratory-confirmed pandemic influenza was 12% (-30; 41).Conclusions
The SISS became an essential tool for pandemic monitoring in Spain. The improved SISS will provide more accurate information on influenza activity in future seasonal or pandemic waves. Using surveillance data, we could not demonstrate the effectiveness of the seasonal 2008-9 vaccine against laboratory-confirmed pandemic influenza. 相似文献422.
Weiser M Gershon AA Rubinstein K Petcu C Ladea M Sima D Podea D Keefe RS Davis JM 《Schizophrenia Research》2012,138(1):35-38
Adenosine agonists produce behavioral effects similar to dopamine antagonists, hence increasing adenosine levels might improve symptoms of schizophrenia. This hypothesis is supported by three single-site studies indicating that allopurinol, which increases adenosine levels, improved symptoms in patients with schizophrenia. We performed a multi-center, 8-week RCT of allopurinol vs. placebo added to anti-psychotic medications in 248 patients with schizophrenia or schizoaffective disorder. Both groups showed improvement in the PANSS (effect size 1.13) and in clinical and cognitive measures. No difference was observed between groups in primary (t=0.01, p=0.992) or secondary outcome measures. These findings do not support allopurinol as a treatment for schizophrenia. 相似文献
423.
424.
Săndulescu M Rusu MC Ciobanu IC Ilie A Jianu AM 《Revue roumaine de morphologie et embryologie》2011,52(3):931-935
The sphenoid sinus is one of the most morphologically variable and surgically important structures of the skull base. Located below the sella turcica, neighbored by parasellar regions, such as the orbital apex, pterygopalatine fossa and lateral sellar region (cavernous sinus), it is clinically related to these and surgically relevant as corridor for various approaches. Moreover, at the sphenoethmoidal junction, important variations occur, most of these related to the presence of the Onodi cells and the intrasinusal protrusions of the optic nerve. That is why any identified and previously undescribed morphological variation at that level must be added to the well-established protocols, clinical and surgical. During a retrospective CT study of the sphenoid sinus anatomical features a previously unreported morphology was encountered and is reported here. It refers to a unilateral sphenoethmoid cell (SEC), Onodi-positive, not only overriding the superior aspect of the sphenoid but also its lateral side to get intimately related to the maxillary nerve. As that SEC expanded medially to the cavernous sinus apex, it altered the usual endosinusal morphological correlations and also added itself within the limits of the Mullan's triangle. It appears so that such postero-infero-lateral extended pneumatization of an Onodi cell alters the surgical landmarks and also can blur clinical pictures, by adding maxillary and pterygopalatine signs and symptoms. 相似文献
425.
Szuhanek C Gâdea Paraschivescu E Sişu AM Motoc A 《Revue roumaine de morphologie et embryologie》2011,52(4):1343-1346
The aim of our study was to identify the most important anatomical landmarks in the cephalometric evaluation of Class III patients and to clarify the morphological characteristics of these cases. A group of 10 Class III orthodontic patients was evaluated in this study. The control group consisted of 10 patients with average occlusion and skeletal characteristics. Digital lateral cephalometric X-rays were performed and different measurements were analyzed. Cephalometric data were evaluated with the CephX specialized software for orthodontic diagnosis and the results were statistically analyzed. The Class III group presented specific characteristics such as prognathic mandible, large gonial angle, short maxillary length, higher lower facial height. These findings can be useful for the diagnosis and treatment planning of orthodontic cases with dental÷keletal anomalies, especially in cases when surgical approach is considered. The surgical decision must be taken after an accurate investigation of the lateral cephalometric parameters. 相似文献
426.
427.
Astrocyte dysfunction and death accompany cerebral ischemia/reperfusion and possibly compromise neuronal survival. Animal studies indicate that neuronal death, neurologic injury, and oxidative molecular modifications are worse in animals exposed to hyperoxic compared to normoxic ventilation during reperfusion after global cerebral ischemia. It is unknown, however, whether ambient O2 affects brain cell survival using in vitro ischemia paradigms where mechanisms of injury to specific cell types can be more thoroughly investigated. This study tested the hypothesis that compared with the supraphysiological level of 20% O2 normally used in cell culture, lower, more physiological O2 levels protect astrocytes from death following oxygen and glucose deprivation. Primary rat cortical astrocytes were cultured under either 7 or 20% O2, exposed to O2, and glucose deprivation for 4 h, and then exposed to normal medium under either 7 or 20% O2. Cell death and 3-nitrotyrosine and 8-hydroxy-2-deoxyguanosine immunoreactivities were assessed at different periods of reoxygenation. Astrocytes exposed to low levels of O2 during reoxygenation undergo less death and exhibit lower levels of protein nitration and nucleic acid oxidation when compared with those under high levels of O2 during reoxygenation. These results support the hypothesis that the 20% O2 normally used in cell culture exacerbates astrocyte death and oxidative stress in an in vitro ischemia/reperfusion model compared to levels that more closely approximate those that exist in vivo. 相似文献
428.
Alafuzoff I Pikkarainen M Arzberger T Thal DR Al-Sarraj S Bell J Bodi I Budka H Capetillo-Zarate E Ferrer I Gelpi E Gentleman S Giaccone G Kavantzas N King A Korkolopoulou P Kovács GG Meyronet D Monoranu C Parchi P Patsouris E Roggendorf W Stadelmann C Streichenberger N Tagliavini F Kretzschmar H 《Acta neuropathologica》2008,115(5):533-546
Amyloid-β-protein (Aβ) is generally assessed by neuropathologists in diagnostics. This BrainNet Europe () (15 centres and 26 participants) study was carried out to investigate the reliability of such an assessment. In the first
part of this trial, tissue microarray sections were stained with the antibody of each centre’s choice. Reflecting the reality,
seven antibodies and a plethora of pretreatment strategies were used. Ninety-two percent of the stainings were of good/acceptable
quality and the estimation of presence of Aβ aggregates yielded good results. However, a poor agreement was reached particularly
regarding quantitative (density) and qualitative (diffuse/cored plaques) results. During a joint meeting, the clone 4G8 was
determined to label best the fleecy/diffuse plaques, and thus, this clone and the formic acid pretreatment technique were
selected for the second part of this study. Subsequently, all stained sections were of good/acceptable quality and again a
high level of concordance of the dichotomized (presence/absence) assessment of plaques and CAA was achieved. However, even
when only one antibody was used, the type of Aβ-aggregates (diffuse/cored), type of vessel and Vonsattel grade, were not reliably
assigned. Furthermore, the quantification of lesions was far from reliable. In line with the first trial, the agreement while
assessing density (some, moderate and many) was unimpressive. In conclusion, we can confirm the utility of immunohistochemical
detection of Aβ-protein in diagnostics and research. It is noteworthy that to reach reproducible results a dichotomized assessment
of Aβ-immunoreactivity rather than quantification and assignment of various types of lesions should be applied, particularly
when comparing results obtained by different neuropathologists.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
429.
Pathological TDP-43 distinguishes sporadic amyotrophic lateral sclerosis from amyotrophic lateral sclerosis with SOD1 mutations 总被引:14,自引:0,他引:14
Mackenzie IR Bigio EH Ince PG Geser F Neumann M Cairns NJ Kwong LK Forman MS Ravits J Stewart H Eisen A McClusky L Kretzschmar HA Monoranu CM Highley JR Kirby J Siddique T Shaw PJ Lee VM Trojanowski JQ 《Annals of neurology》2007,61(5):427-434
OBJECTIVE: Amyotrophic lateral sclerosis (ALS) is a common, fatal motor neuron disorder with no effective treatment. Approximately 10% of cases are familial ALS (FALS), and the most common genetic abnormality is superoxide dismutase-1 (SOD1) mutations. Most ALS research in the past decade has focused on the neurotoxicity of mutant SOD1, and this knowledge has directed therapeutic strategies. We recently identified TDP-43 as the major pathological protein in sporadic ALS. In this study, we investigated TDP-43 in a larger series of ALS cases (n = 111), including familial cases with and without SOD1 mutations. METHODS: Ubiquitin and TDP-43 immunohistochemistry was performed on postmortem tissue from sporadic ALS (n = 59), ALS with SOD1 mutations (n = 15), SOD-1-negative FALS (n = 11), and ALS with dementia (n = 26). Biochemical analysis was performed on representative cases from each group. RESULTS: All cases of sporadic ALS, ALS with dementia, and SOD1-negative FALS had neuronal and glial inclusions that were immunoreactive for both ubiquitin and TDP-43. Cases with SOD1 mutations had ubiquitin-positive neuronal inclusions; however, no cases were immunoreactive for TDP-43. Biochemical analysis of postmortem tissue from sporadic ALS and SOD1-negative FALS demonstrated pathological forms of TDP-43 that were absent in cases with SOD1 mutations. INTERPRETATION: These findings implicate pathological TDP-43 in the pathogenesis of sporadic ALS. In contrast, the absence of pathological TDP-43 in cases with SOD1 mutations implies that motor neuron degeneration in these cases may result from a different mechanism, and that cases with SOD1 mutations may not be the familial counterpart of sporadic ALS. 相似文献
430.
Sinziana-Andra Ghitoi Mariana Achie Georgeta Camelia Cozaru Manuela Enciu Elena Matei Antonela-Anca Nicolau Gabriela Izabela Bltescu Nicolae Dobrin Roxana Elena Cîrjaliu Ariadna Petronela Fildan 《Medicine》2022,101(30)
The molecular basis of the evaluation of children suspected of having disorders of surfactant proteins is still under discussion. In this study, we aimed to describe the morphological characteristics and to evaluate the immunohistochemical expression of surfactant proteins (surfactant protein A [SPA], surfactant protein B, and pro-surfactant protein C) in the preterm twins that deceased due to unexplained respiratory distress syndrome (n = 12). Results showed statistically significant positive correlations between surfactant protein B expressions and pulmonary hemorrhage (ρ = 0.678; P < .05), SPA levels, and Apgar score (ρ = 0.605; P < .05) and also expressions of SPA and bronchopneumonia (ρ = 0.695; P < .05). The fetuses and neonates of the same gestational age showed differences among surfactant proteins regarding the immunostaining expression. Our data evidence a marked interindividual variability in the expression of all 3 surfactant proteins among the cases analyzed (n = 12), suggesting the intervention of some individual and epigenetic factors during gestation that might influence surfactant protein production and consequently survival rate. 相似文献