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101.
The surface of the maxillary and mandibular incisors of Spermophilus undulatus long-tailed ground squirrels, including those born in the current year and those that have hibernated (trapped one month
or later after hibernation) is studied. The presence of daily growth increments on the incisors’ surface allows the evaluation
of the eruption rate of the incisors; a specific change in the character of the growth increments corresponds to winter hibernation
(hibernation zone), which serves as the time mark. Ratio between the eruption rates of the maxillary and mandibular incisors
typical for rodents is found in young-of-the-year and some animals after hibernation. In these animals the eruption rate of
the mandibular incisors is higher than the eruption rate of the maxillary incisors and can be taken as proportional to their
length. In individuals that have hibernated and show proportional eruption of the incisors, the proportions of the total length
of the incisor formed before hibernation zone are equal for the maxillary and mandibular incisors. In the individuals that
also have hibernated and show the ratio between the total length of the maxillary and mandibular incisors typical for rodents,
the eruption rate of the mandibular incisor is equal to or less than the eruption rate of the maxillary incisor and the proportion
of the incisor formed before hibernation is greater in the mandibular incisor than in the maxillary. This disproportionate
pattern of incisor eruption is not typical for rodents and is a result of inequal attrition of the maxillary and mandibular
incisors, which ultimately results in the normal ratio of the total length of the maxillary and mandibular incisors. 相似文献
102.
GW Patton R Stephens IA Sidorov X Xiao RA Lempicki DS Dimitrov RH Shoemaker G Tudor 《BMC bioinformatics》2006,7(1):81
Background
Microarrays used for gene expression studies yield large amounts of data. The processing of such data typically leads to lists of differentially-regulated genes. A common terminal data analysis step is to map pathways of potentially interrelated genes. 相似文献103.
104.
E. P. Nartshuk A. K. Bagachanova T. G. Evdokarova N. K. Potapova 《Entomological Review》2008,88(8):898-903
Sixty-one species of grassflies (Diptera, Chloropidae) have been found in the meadows in the middle Lena valley, Central Yakutia. Differences between the grassfly taxocenoses of different parts of the valley depend on specific features of a particular plant community. The dominant and subdominant chloropid species are distinguished. The differences of the riparian fauna from the complexes inhabiting the alases in Yakutia are shown. Six species of grassflies are recorded for Yakutia for the first time, all of them belonging to the subfamily Oscinellinae: Polyodaspis ruficornis Macquart, Tricimba cincta Meigen, Aphanotrigonum trilineatum Meigen, Trachysiphonella scutellata v. Roser, Rhopalopterum anthracinum Meigen, and Rh. fasciolum Meigen 相似文献
105.
Potapova IA Brink PR Cohen IS Doronin SV 《The Journal of biological chemistry》2008,283(19):13100-13107
Culture-expanded human mesenchymal stem cells (hMSCs) are increasingly used in a variety of preclinical and clinical studies. However, these cells have a low rate of engraftment to bone marrow or damaged tissues. Several laboratories have shown that during isolation and subculturing mesenchymal stem cells quickly lose the expression of CXCR4, the key receptor responsible for lymphocytes and hematopoietic stem cell homing. Here we show that culturing of hMSCs as three-dimensional aggregates (hMSC spheroids) restores CXCR4 functional expression. Expression of CXCR4 inversely correlates with the secretion of SDF-1 by hMSCs. Cells from hMSC spheroids up-regulate expression of CD49b, the alpha2 integrin subunit, and suppress the expression of CD49d, the alpha4 integrin subunit. Transfer of cells from the spheroids back to a monolayer suppresses the expression of CXCR4 and CD49b and restores the expression of CD49d. Treatment of cells from the spheroids with SDF-1 leads to CXCR4 internalization and activation of ERK-1,2. Adhesion of hMSCs to human umbilical vein endothelial cells (HUVECs) was investigated. SDF-1, AMD-3100, or exposure of HUVECs to hypoxia did not affect adhesion of hMSCs from a monolayer to HUVECs. Adhesion of cells from hMSC spheroids to HUVECs was stimulated by SDF-1, AMD-3100, or by exposure of HUVECs to hypoxia. Stimulatory effects of hypoxia and addition of SDF-1 or AMD-3100 were not additive. Overall, our data indicate that the expression of CXCR4 by hMSCs regulates hMSC adhesion to endothelial cells. 相似文献
106.
VESELOV II 《Mikrobiologiia》1951,20(6):550-555
107.
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110.
Nataliya Babyshkina Elena Malinovskaya Mariya Nazarenko Mariya Koval Polina Gervas Olga Potapova Elena Slonimskaya Nadejda Cherdyntseva 《Gene》2013
This study aimed to investigate the relationship of ten single nucleotide polymorphisms (SNPs) in the MTHFR, MTR, MTRR, DHFR, MTHFD1, TS, RFC1 and DNMT3b genes with cancer survival, therapeutic response to neoadjuvant chemotherapy and clinicopathological characteristics in 300 pre- and postmenopausal breast cancer patients of a Russian Western Siberian population. We found that the MTHFR 677CT genotype as well as combination of MTHFR 677CT and 677TT genotype was related to tumor size and estrogen-positive status in postmenopausal group. The RFC1 80А allele was associated with an increased risk of lymph node metastases among postmenopausal women. The MTHFR 677TT genotype was significantly correlated with a better progression-free survival in premenopausal patients. In contrast, a worse outcome was observed in this group patient with MTHFD1 1958AA genotype. In the multivariate analysis, the MTHFD1 1958AA genotype was identified as an independent prognostic factor for premenopausal breast cancer survival. Our findings provide evidence for associations of breast cancer survival with folate-related SNPs in a population of Western Siberian region of Russia and the MTHFD1 (1958G>A) may have additional prognostic value especially among premenopausal patients. 相似文献