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Endomicrobium proavitum,the first isolate of Endomicrobia class. nov. (phylum Elusimicrobia) – an ultramicrobacterium with an unusual cell cycle that fixes nitrogen with a Group IV nitrogenase 下载免费PDF全文
Hao Zheng Carsten Dietrich Renate Radek Andreas Brune 《Environmental microbiology》2016,18(1):191-204
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Kristýna Nmejcov Ivana Tich Michaela Brt Ondej Kodet Miroslav Dra Radek Jaka Romana Michlkov Pavel Dundr 《Pigment cell & melanoma research》2019,32(3):412-423
The objective of our study was to compare the five different scoring methods of tumor‐infiltrating lymphocytes (TILs) assessment in a group of 213 cases of superficial spreading and nodular melanoma. The scoring methods include (a) Clark scoring; (b) Melanoma Institute Australia system; (c) scoring system used in the study of Saldanha et al.; (d) scoring system used in the TCGA study and modified by Park et al.; and (e) the system recently proposed by the “International Immuno‐Oncology Biomarker Working Group” for TILs scoring in all solid tumors. Prediction of survival with three main outcomes—disease‐specific‐free survival, local recurrence‐free survival, and distant metastasis‐free survival—was evaluated. The prognostic value of TILs showed statistical significance in univariate analysis regarding all three of the outcomes only for three of the five evaluated methods; the Clark scoring, the Melanoma Institute Australia system, and the system proposed by the “International Immuno‐Oncology Biomarker Working Group”. However, in multivariate analysis with covariants including Breslow thickness, type of melanoma, location, sex, and age, we did not find TILs to be an independent prognostic factor. 相似文献
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Oulehle Filip Wright Richard F. Svoboda Miroslav Bače Radek Matějka Karel Kaňa Jiří Hruška Jakub Couture Raoul-Marie Kopáček Jiří 《Ecosystems》2019,22(4):725-741
Ecosystems - Forest ecosystems worldwide are subjected to human-induced stressors, including eutrophication and acidification, and to natural disturbances (for example, insect infestation,... 相似文献
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Litvín Radek Bína David Herbstová Miroslava Pazderník Marek Kotabová Eva Gardian Zdenko Trtílek Martin Prášil Ondřej Vácha František 《Photosynthesis research》2019,142(2):137-151
Photosynthesis Research - Survival of phototrophic organisms depends on their ability to collect and convert enough light energy to support their metabolism. Phototrophs can extend their absorption... 相似文献
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We have recently shown that epidermal growth factor (EGF) strongly stimulates expansion of porcine oocyte-cumulus complexes (OCCs) isolated from large follicles (>6 mm) and does not promote expansion of OCCs from small (3-4-mm) follicles. In order to elucidate the role of EGF in OCCs expansion, in the present study, we first examined the presence of EGF receptors (EGFRs) in cumulus cells isolated from follicles of different sizes. Surprisingly, immunoblotting showed that cumulus cells obtained from all follicular size categories contained similar amounts of EGFR protein. On the other hand, we found a dramatic difference in the pattern of protein tyrosine phosphorylation in a comparison of cumulus cells isolated from small and large follicles treated by EGF. Furthermore, tyrosine-phosphorylated EGFR was specifically immunoprecipitated with antiphosphotyrosine antibodies from EGF-treated cumulus cells isolated from the large follicles. This result strongly indicates that only OCCs from the large follicles contain mature EGFRs that are capable of becoming activated by EGF. Remarkably, preincubation of cumulus cells from small follicles (3-4 mm) with FSH strongly increased EGF-stimulated tyrosine phosphorylation to levels comparable with OCCs from large follicles. The FSH-dependent activation of EGFRs was beneficial for expansion of OCCs isolated from the small follicles since OCCs treated sequentially by FSH (3 h) and EGF (1 h) underwent expansion significantly better then OCCs cultured in FSH or EGF alone. We conclude that a FSH-dependent pathway has an important role in the maturation of the EGFR in cumulus cells and that activation of EGFR-dependent signaling is sufficient to induce expansion. 相似文献
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Light and electron microscopic study of a Rickettsiella species from the cockroach Blatta orientalis
Radek R 《Journal of invertebrate pathology》2000,76(4):249-256
An infection with Rickettsiella sp. was responsible for an illness causing heavy body swelling in the Oriental cockroach Blatta orientalis. Reproduction of the colony stagnated. Vacuoles with parasitic bacteria occurred mainly in the fat body, but also in nearly all other organs, such as gut epithelium, Malpighian tubules, blood cells, and ovarioles. The parasites clearly differed from the symbiotic bacteria of the genus Blattabacterium, which regularly occur in the mycetocytes of B. orientalis. The vacuoles contained four stages of Rickettsiella: (1) infectious, electron-dense, rod-like elementary bodies (mean size 300 x 145 nm); (2) an electron-dense, flat intermedium stage, called flat body (mean size 515 x 255 x 125 nm); (3) an electron-light, spherical intermedium stage, called condensing sphere (mean size 340 nm); portions of cytoplasm condensed crescent-like at the border or in the center of the cell; and (4) large, spherical, electron-light initial bodies that multiplied by binary fission (mean size 600 nm). The initial bodies had a three-layered cell boundary, but all other stages had a five-layered cell boundary. Elementary and flat bodies contained an electron-light, oblique lamella and an oval structure with an array of ribosome-like granules, respectively. In contrast to other species of Rickettsiella, crystal formation or multiple division did not occur. The described species of Rickettsiella is different from "R. blattae," which belongs to the R. popilliae group. Instead, it shares more similarities with the R. chironomi group. To avoid confusion, it was provisionally named "R. crassificans." 相似文献
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The cockroach entomopoxvirus caused a chronic infection in cultures of the German cockroach Blattella germanica. Heavily infected specimens showed a reduced mobility. Ellipsoid virus occlusion bodies (8 x 5 to 19 x 12 microm) were found intracellularly in tracheole cells, in the hypodermis, in fat body cells, and in muscles. Several hundred virus particles were integrated in a single occlusion body (OB), their long axis being oriented axially. Ovoid viroids measured 320 x 190 nm and possessed a unilateral, concave core and one lateral body. Starting occlusion, small granules attached to the virus particles which later transformed to a beaded, wavy envelope. An initial halo around the occluded virions disappeared in more central regions of the OB. Virus particles were formed either in a dense cytoplasmic area containing electron-dense viroids, or in a loosely aggregated viroplasm. In the latter, developmental stages were mainly represented by spheres with double membranes enclosing granular material. Spindles and larger crystal-like virus-free inclusion bodies occurred in the cytoplasm. The cytoplasm of infected cells appeared degenerated and the chromatin of the nuclei condensed at the periphery or disintegrated. Taxonomically, the described virus exhibits features of both EPV genus A and EPV genus B. Provisory it is named Blattella germanica EPV (BgEPV). A possible use of the cockroach EPV as a biological control agent is discussed. 相似文献
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Edwin C. M. Mariman Radek Szklarczyk Freek G. Bouwman Erik E. J. G. Aller Marleen A. van Baak Ping Wang 《Genes & nutrition》2015,10(4)
Worldwide, the incidence of obesity has increased dramatically over the past decades. More knowledge about the complex etiology of obesity is needed in order to find additional approaches for treatment and prevention. Investigating the exome sequencing data of 30 extremely obese subjects (BMI 45–65 kg/m2) shows that predicted damaging missense variants in olfactory receptor genes on chromosome 1q and rare predicted damaging variants in the protocadherin (PCDH) beta-cluster genes on chromosome 5q31, reported in our previous work, co-localize in subjects with extreme obesity. This implies a synergistic effect between genetic variation in these gene clusters in the predisposition to extreme obesity. Evidence for a general involvement of the olfactory transduction pathway on itself could not be found. Bioinformatic analysis indicates a specific involvement of the PCDH beta-cluster genes in controlling tissue development. Further mechanistic insight needs to await the identification of the ligands of the 1q olfactory receptors. Eventually, this may provide the possibility to manipulate food flavor in a way to reduce the risk of overeating and of extreme obesity in genetically predisposed subjects.