全文获取类型
收费全文 | 213篇 |
免费 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 10篇 |
2015年 | 9篇 |
2014年 | 9篇 |
2013年 | 20篇 |
2012年 | 27篇 |
2011年 | 20篇 |
2010年 | 12篇 |
2009年 | 9篇 |
2008年 | 11篇 |
2007年 | 18篇 |
2006年 | 10篇 |
2005年 | 10篇 |
2004年 | 8篇 |
2003年 | 3篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
排序方式: 共有220条查询结果,搜索用时 15 毫秒
101.
Turner ML Cockerell EJ Brereton HM Badenoch PR Tea M Coster DJ Williams KA 《International journal for parasitology》2005,35(9):981-990
Acanthamoeba species are ubiquitous soil and freshwater protozoa that have been associated with infections of the human brain, skin, lungs and eyes. Our aim was to develop specific antibodies to aid in rapid and specific diagnosis of clinically important isolates. Mice were variously immunised with live mixtures of Acanthamoeba castellanii strain 112 (AC112) trophozoites and cysts, or with sonicated, formalin-fixed or heat-treated trophozoites, or with a trophozoite membrane preparation. Eight hybridoma cell lines secreting monoclonal antibodies reactive with A. castellanii epitopes were generated. Seven of the new antibodies (designated AMEC1-3 and MTAC1-4) were isotyped as IgMkappa and one (MTAC5) as IgG1kappa. All of the novel antibodies bound to AC112 cysts, and MTAC4 and MTAC5 also bound to trophozoites as measured by flow cytometry on unfixed cells. Single chain antibody fragments that retained parental antibody binding characteristics were engineered from three of the hybridomas (AMEC1, MTAC3 and MTAC4). Four monoclonal antibodies (AMEC1, AMEC3, MTAC1, MTAC3) bound reliably to unfixed cysts of clinical isolates of A. castellanii (two strains) and Acanthamoeba polyphaga (two strains), belonging to Pussard-Pons morphological group II, and to Acanthamoeba lenticulata and Acanthamoeba culbertsoni, belonging to Pussard-Pons morphological group III. None of the antibodies bound to cysts or trophozoites of the environmental group I species, Acanthamoeba tubiashi. Antibodies AMEC1, MTAC3, MTAC4 and MTAC5 reacted with buffered formalin-fixed AC112 by immunohistochemistry, and also stained Acanthamoeba in sections of infected rat cornea and buffered formalin-fixed, paraffin-embedded infected human cornea. These antibodies may be useful in diagnosing pathogenic Acanthamoeba species in clinical specimens, provided that cysts are present. 相似文献
102.
An attachment tip and pili-like structures in insect- and plant-pathogenic spiroplasmas of the class Mollicutes 总被引:1,自引:0,他引:1
Ultrastructural studies using scanning electron microscopy (SEM), negative-staining transmission electron microscopy (TEM), and thin-sectioning TEM on four species of Spiroplasma, in vitro and/or in vivo, indicated that their helices commonly possess one tapered end (tip structure) and one blunt or round end. These tip structures appeared morphologically different from the rest of the helix, exhibiting an electron-dense conical or rod-shaped core. In thin sections of the midgut of the leafhopper Dalbulus elimatus, the tip structures of Spiroplasma kunkelii in the midgut lumen were mostly aligned between microvilli, perpendicular to the apical plasma membrane of epithelial cells. These tip structures appeared frequently attached or closely apposed to the plasma membrane, in which cup-shaped invaginations close to the tips were observed. Pleomorphic forms of spiroplasma, enclosed in membranous vesicles, were found in the cytoplasm of the midgut epithelial cells. These findings suggest that the tip structure may be involved in the orientation and attachment of spiroplasma helices in relation to their host cells, and thus may be functionally comparable to the attachment organelle of mycoplasmas. Additionally, pili-like structures were observed by negative-staining TEM on the surface of Spiroplasma melliferum, and in thin sections of S. kunkelii infecting the leafhopper vector Dalbulus gelbus.
Abbreviations
CSS
Corn stunt spiroplasma
-
SEM
Scanning electron microscopy
-
TBS
Tris-buffered saline
-
TEM
Transmission electron microscopy 相似文献
103.
104.
Sogorić S Rukavina TV Brborović O Vlahugić A Zganec N Oresković S 《Collegium antropologicum》2005,29(1):111-119
The subject of this paper is how to incorporate a multi-disciplinary and inter-sectored approach into development of public health policy and plans at the local (county) level in Croatia by educational program. Method used was the public health capacity building program "Health--Plan for it", which was developed with the aim to assist the counties to overcome recognized weaknesses and introduce more effective and efficient local public health practices. Two main instruments were used: Local Public Health Practice Performance Measures Instrument, and Basic Priority Rating System. This program has helped counties to asses population health needs in a participatory manner, to plan for health and, ultimately, assure provision of the right kind and quality of services (better tailored to population health needs). This program's benefits are going beyond and above the county level. It provides support for the Healthy Cities project locally, and facilitates changes in national policymaking body's mindset that a "one-size-fits-all" approach is sufficient. 相似文献
105.
Elina Eränkö Mette Ilander Mirja Tuomiranta Antti Mäkitie Tea Lassila Anna Kreutzman Paula Klemetti Satu Mustjoki Katariina Hannula-Jouppi Annamari Ranki 《Orphanet journal of rare diseases》2018,13(1):213
Background
Netherton syndrome (NS) is a rare life-threatening syndrome caused by SPINK5 mutations leading to a skin barrier defect and a severe atopic diathesis. NS patients are prone to bacterial infections, but the understanding of the underlying immune deficiency is incomplete.Results
We analyzed blood lymphocyte phenotypes and function in relation to clinical infections in 11 Finnish NS patients, aged 3 to 17?years, and healthy age-matched controls. The proportion of B cells (CD19+) and naïve B cells (CD27?, IgD+) were high while memory B cells (CD27+) and switched memory B cells (CD27+IgM?IgD?), crucial for the secondary response to pathogens, was below or in the lowest quartile of the reference values in 8/11 (73%) and 9/11 (82%) patients, respectively. The proportion of activated non-differentiated B cells (CD21low, CD38low) was below or in the lowest quartile of the reference values in 10/11 (91%) patients. Despite normal T cell counts, the proportion of naïve CD4+ T cells was reduced significantly and the proportion of CD8+ T central memory significantly elevated. An increased proportion of CD57+ CD8+ T cells indicated increased differentiation potential of the T cells. The proportion of cytotoxic NK cells was elevated in NS patients in phenotypic analysis based on CD56DIM, CD16+ and CD27? NK cells but in functional analysis, decreased expression of CD107a/b indicated impaired cytotoxicity.The T and NK cell phenotype seen in NS patients also significantly differed from that of age-matched atopic dermatitis (AD) patients, indicating a distinctive profile in NS. The frequency of skin infections correlated with the proportion of CD62L+ T cells, naïve CD4+ and CD27+ CD8+ T cells and with activated B cells. Clinically beneficial intravenous immunoglobulin therapy (IVIG) increased naïve T cells and terminal differentiated effector memory CD8+ cells and decreased the proportion of activated B cells and plasmablasts in three patients studied.Conclusions
This study shows novel quantitative and functional aberrations in several lymphocyte subpopulations, which correlate with the frequency of infections in patients with Netherton syndrome. IVIG therapy normalized some dysbalancies and was clinically beneficial.106.
107.
Andrea Weghofer Muy-Kheng Tea David H. Barad Ann Kim Christian F. Singer Klaus Wagner Norbert Gleicher 《PloS one》2012,7(9)
BRCA1/2 mutations and recently described constitutional FMR1 genotypes have, independently, been associated with prematurely diminished ovarian reserve. Whether they interrelate in distribution, and whether observed effects of BRCA1/2 and FMR1 on ovaries are independent of each other, is unknown. In a prospective comparative cohort study, we, therefore, investigated the distribution of constitutional FMR1 genotypes, normal (norm), heterozygous (het) and homozygous (hom), and of their respective sub-genotypes (high/low), in 99 BRCA1/2 mutation-positive women and 410 female controls to determine whether distribution patterns differed between study and control patients. In contrast to controls, BRCA1/2 carriers demonstrated almost complete absence of all constitutional FMR1 genotypes except for sub-genotypes with low (CGG n<26) alleles. Cross tabulation between BRCA1/2-positive patients and controls confirmed significant group membership, related to FMR1 distribution (P<0.0001). These results offer as most likely explanation the conclusion that BRCA1/2 mutations are embryo-lethal, unless rescued by low (CGG n<26) FMR1 sub-genotypes, present in approximately one quarter of all women. Women with low FMR1 sub-genotypes, therefore, should reflect increased BRCA1/2-associated cancer risks, while the remaining approximately 75 percent should face almost no such risks. If confirmed, this observation offers opportunities for more efficient and less costly BRCA1/2 cancer screening. The study also suggests that previously reported risk towards prematurely diminished ovarian reserve in association with BRCA mutations is FMR1-mediated, and offers a possible explanation for the so-called “BRCA paradox” by raising the possibility that the widely perceived BRCA1/2-associated tumor risk is actually FMR1-mediated. 相似文献
108.
109.
Jun Chen Yoshiaki Tsuda Michael Stocks Thomas K?llman Nannan Xu Katri K?rkk?inen Tea Huotari Vladimir L. Semerikov Giovanni G. Vendramin Martin Lascoux 《Genetics》2014,197(3):1025-1038
Parallel clines in different species, or in different geographical regions of the same species, are an important source of information on the genetic basis of local adaptation. We recently detected latitudinal clines in SNPs frequencies and gene expression of candidate genes for growth cessation in Scandinavian populations of Norway spruce (Picea abies). Here we test whether the same clines are also present in Siberian spruce (P. obovata), a close relative of Norway spruce with a different Quaternary history. We sequenced nine candidate genes and 27 control loci and genotyped 14 SSR loci in six populations of P. obovata located along the Yenisei river from latitude 56°N to latitude 67°N. In contrast to Scandinavian Norway spruce that both departs from the standard neutral model (SNM) and shows a clear population structure, Siberian spruce populations along the Yenisei do not depart from the SNM and are genetically unstructured. Nonetheless, as in Norway spruce, growth cessation is significantly clinal. Polymorphisms in photoperiodic (FTL2) and circadian clock (Gigantea, GI, PRR3) genes also show significant clinal variation and/or evidence of local selection. In GI, one of the variants is the same as in Norway spruce. Finally, a strong cline in gene expression is observed for FTL2, but not for GI. These results, together with recent physiological studies, confirm the key role played by FTL2 and circadian clock genes in the control of growth cessation in spruce species and suggest the presence of parallel adaptation in these two species. 相似文献
110.
Fabio Cericola Ezio Portis Sergio Lanteri Laura Toppino Lorenzo Barchi Nazzareno Acciarri Laura Pulcini Tea Sala Giuseppe Leonardo Rotino 《BMC genomics》2014,15(1)