全文获取类型
收费全文 | 574篇 |
免费 | 40篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 11篇 |
妇产科学 | 6篇 |
基础医学 | 85篇 |
口腔科学 | 75篇 |
临床医学 | 70篇 |
内科学 | 92篇 |
皮肤病学 | 6篇 |
神经病学 | 39篇 |
特种医学 | 16篇 |
外科学 | 70篇 |
综合类 | 6篇 |
预防医学 | 49篇 |
眼科学 | 18篇 |
药学 | 52篇 |
中国医学 | 7篇 |
肿瘤学 | 12篇 |
出版年
2023年 | 10篇 |
2022年 | 28篇 |
2021年 | 29篇 |
2020年 | 17篇 |
2019年 | 18篇 |
2018年 | 28篇 |
2017年 | 18篇 |
2016年 | 21篇 |
2015年 | 14篇 |
2014年 | 21篇 |
2013年 | 36篇 |
2012年 | 41篇 |
2011年 | 53篇 |
2010年 | 10篇 |
2009年 | 21篇 |
2008年 | 44篇 |
2007年 | 43篇 |
2006年 | 28篇 |
2005年 | 21篇 |
2004年 | 22篇 |
2003年 | 22篇 |
2002年 | 22篇 |
2001年 | 9篇 |
2000年 | 5篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1990年 | 1篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有615条查询结果,搜索用时 15 毫秒
1.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献
2.
Propriospinal myoclonus: utility of magnetic resonance diffusion tensor imaging and fiber tracking. 总被引:1,自引:0,他引:1
Emmanuel Roze Emmanuelle Apartis Marie Vidailhet Valérie Cochen Yara Beaugendre Jean-Marc Trocello Pierre Lasjaunias Denis Ducreux 《Movement disorders》2007,22(10):1506-1509
Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus. 相似文献
3.
Claudio Oliveira Fausto Foresti Marcos Guilherme Rigolino Yara Aiko Tabata 《Chromosome research》1995,3(3):182-190
The surface-spreading synaptonemal complex (SC) technique was employed to analyze spermatocytes and oocytes of rainbow trout in order to visualize the process of autosome and sex chromosome synapsis in this species. The structure of lateral elements (LEs) of the SC and the chromosome synapsis process at the stages of leptotene, zygotene and pachytene are described. Comparative analysis of SCs of spermatocytes and oocytes showed a difference in the synaptic process, i.e. in spermatocytes all LEs were synapsed before the appearance of centromeric regions in the biarmed elements, while in the oocytes some fully synapsed LEs, including the centromeric region of the biarmed elements, were found together with fully or partially unsynapsed LEs. In males the sex chromosome synapsis starts only after all autosomes have synapsed. Irregular synapses involving three or four LEs were found in 3.4% of the cells analyzed in mid or late zygotene. Multivalents were found in males and females. Some aspects of initial meiotic development and their implications in rainbow trout cytogenetics, genetics and evolution are discussed. 相似文献
4.
Long-term protective immune response elicited by vaccination with an expression genomic library of Toxoplasma gondii 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Fachado A Rodriguez A Molina J Silvério JC Marino AP Pinto LM Angel SO Infante JF Traub-Cseko Y Amendoeira RR Lannes-Vieira J 《Infection and immunity》2003,71(9):5407-5411
Immunization of BALB/c mice with an expression genomic library of Toxoplasma gondii induces a Th1-type immune response, with recognition of several T. gondii proteins (21 to 117 kDa) and long-term protective immunity against a lethal challenge. These results support further investigations to achieve a multicomponent anti-T. gondii DNA vaccine. 相似文献
5.
Abath FG Xavier EM Allen R Gomes YM Lucena-Silva N Baliza M Simpson AJ 《Parasitology research》2000,86(9):745-752
Sm13, a 13-kDa Schistosoma mansoni tegumental antigen, is one of the principal polypeptides recognized by antibodies from mice protectively vaccinated with
adult-worm tegumental membranes. To obtain the complete gene encoding Sm13 we subcloned and sequenced a cDNA and a fragment
of a genomic clone. The collated sequence contains 1088 nucleotides and represents the full-length open reading frame of the
gene, encoding a protein of 104 amino acids with a calculated molecular mass of 11,923 Da, compatible with the native protein
identified in the tegumental membranes. The sequence derived from genomic DNA contains a 45-nucleotide intron. The analysis
of the predicted protein suggests the presence of both N- and C-terminal hydrophobic membrane-spanning segments, and the coding
region contains no homology in the currently available data bases. Additionally, the coding region is preceded by putative
CCAAT and TATA boxes that may be involved in the control of expression. Western-blot analysis and indirect immunofluorescence
resulted in the identification of a 13-kDa protein (Sm13) in the tegument of adult worms. The present study reveals that Sm13
behaves as an integral membrane protein upon partitioning in Triton X-114 and that it is present in worms of 3 weeks or older
but not in schistosomula or miracidia. Moreover, it is also specifically recognized by sera from some schistosomiasis patients
in enzyme-linked immunosorbent assay and Western-blot analysis, suggesting that it is immunogenic in human schistosomiasis.
Received: 17 February 2000 / Accepted: 22 March 2000 相似文献
6.
Carolina Battellino Roxane Piazza Ana M M da Silva Yara Cury Sandra H P Farsky 《Toxicon》2003,41(5):583-593
Intravenous administration of antibothropic antivenom (BAv) neutralises the systemic effects, but does not efficiently reverse the local symptoms elicited by the Bothrops jararaca venom (BjV). The mechanisms involved in this poor protection have not been clarified. In this work, intravital microscopy studies were carried out to determine the efficacy of different schedules of BAv treatment on local effects evoked by topical application of BjV in the microcirculatory network of the internal spermatic fascia of Wistar rats. Results demonstrated that BAv administration 15 min before, simultaneously with, or 15 min after BjV application did not totally reverse the local symptoms, represented by disturbances of coagulation, development of haemorrhage lesions, vascular permeability increase and increment on leukocyte-endothelium interactions. This lack of effectiveness neither reflects an inadequate amount of specific antibodies in the antivenom against toxins responsible for local effects nor an insufficient dose of circulating BAv during the assays. Administration of fluorescein isothiocyanate (FITC) labelled-BAv showed the dynamics of distribution of the antivenom in the microcirculatory network. Images obtained from prior and simultaneously treated animals showed that the antivenom remains at luminal side of vessels before venom application, and the latency time to antivenom leakage is coincidental to that for local effects evoked by the venom. In addition, images from posterior treatment demonstrated that the intense alterations in the microcirculatory network impair antivenom distribution at the site of injection. Together, our data show that the lack of effectiveness of antivenom therapy is due to impaired and delayed venom and antivenom interaction at the site of injury. 相似文献
7.
Takahashi S Matsuura M Tanabe E Yara K Nonaka K Fukura Y Kikuchi M Kojima T 《Psychiatry and clinical neurosciences》2000,54(2):153-156
This study was undertaken to examine whether males develop schizophrenia at a younger age than females, and whether temporal socioeconomic change affects the age at onset of schizophrenia. The subjects were 848 ICD-9 schizophrenics who were admitted to Nihon University Hospital, Tokyo, Japan, during the period of 1955-64 (n = 468 (214 males and 254 females), group A) or during the period of 1982-91 (n = 380 (220 males and 160 females). group B). Schizophrenic males showed an earlier age at onset than schizophrenic females. However, the mean age at onset of schizophrenia did not differ significantly between group A and group B. These results indicate that the gender difference in age at onset of schizophrenia has not been influenced by temporal socioeconomic change. 相似文献
8.
Cludia Farinha Patrícia Barreto Rita Coimbra Adela Iutis Maria Luz Cachulo Jos Cunha-Vaz Yara T. E. Lechanteur Carel B. Hoyng Rufino Silva 《Investigative ophthalmology & visual science》2022,63(9)
PurposeTo determine the association between rare genetic variants in complement factor H (CFH) and phenotypic features in age-related macular degeneration (AMD) patients from the Coimbra Eye Study (CES).MethodsAMD patients from the Incidence CES () underwent ophthalmologic examination and color fundus photography, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence, and near-infrared imaging. Multimodal phenotypic characterization was carried out in a centralized reading center. The coding and splice-site regions of the CFH gene were sequenced through single-molecule molecular inversion probe–based next-generation sequencing in association with the EYE-RISK consortium. Variants with minor allele frequency <0.05 resulting in splice-site or protein change were selected. Differences in phenotypic features between carriers and noncarriers were analyzed using generalized estimated equations logistic regression models, considering intereye correlations.ResultsWe included 39 eyes of 23 patients carrying rare CFH variants and 284 eyes of 188 noncarriers. Carrier status was associated with having higher drusen burden in the macula in the inner Early Treatment Diabetic Retinopathy Study circle (odds ratio [OR], 5.44 [95% confidence interval {CI}, 1.61–18.37]; P = 0.006), outer circle (OR, 4.37 [95% CI, 1.07–17.77]; P = 0.04), and full grid (OR, 4.82 [95% CI, 1.13–20.52]; P = 0.033). In SD-OCT, a lower total macular volume and lower inner retinal layers’ volume (OR, 0.449 [95% CI, 0.226–0.894]; P = 0.023; OR, 0.496 [95% CI, 0.252–0.979]; P = 0.043) and pigment epithelial detachments (PEDs) (OR, 5.24 [95% CI, 1.08–25.44]; P = 0.04) were associated with carrying a rare CFH variant. Carriers with subretinal drusenoid deposits (SDD) had the rare variant P258L in all cases except one.ConclusionsWe identified in our cohort phenotypic differences between carriers and noncarriers of rare variants in the CFH gene. Carriers had more severe disease, namely superior drusen burden, PEDs, and thinner retinas. The rare variant P258L may be associated with SDD. Carriers are probably at increased risk of progression. NCT02748824相似文献
9.
10.
Gabriela Datsch Bennemann Emilia Addison Machado Moreira Leticia Cristina Radin Pereira Maiara Brusco de Freitas Diane de Oliveira Julia Carvalho Ventura Eduardo Benedetti Parisotto Yara Maria Franco Moreno Erasmo Benicio Santos Moraes Trindade Eliana Barbosa Norberto Ludwig Neto Danilo Wilhelm Filho 《The clinical respiratory journal》2022,16(6):475
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF. 相似文献