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981.
Summary Many plasmids belonging to the F incompatibility groups contain more than one basic replicon. The chimeric plasmid pCG86 is an example of such a multireplicon plasmid. The two basic replicons of pCG86, RepFIIA/FIC and RepFIB have been cloned and re-ligated, the copy numbers of the clones have been determined, and the incompatibility behavior of plasmids containing the ligated replicons and the individual replicons has been studied. The bireplicon plasmids are not expected to be incompatible as recipients with monoreplicon RepFIB or RepFIIA/RepFIC plasmids, since when one replicon is challenged by an incoming replicon, the other should be able to handle the plasmid's replication. In our studies, we found that challenge with either monoreplicon plasmid resulted in incompatibility. This incompatibility was increased in bireplicon plasmids in which RepFIB was duplicated. We conclude that in the bireplicon plasmids, challenging the replication control of one replicon by an incompatible plasmid can interfere with the replication originating from the second replicon. 相似文献
982.
983.
Renata Brelińska Elzbieta Kaczmarek Jerzy B. Warchoł Jan Jaroszewski 《Cell and tissue research》1985,240(2):473-478
Summary This study attempted to define reciprocal positions of cell types within the thymus. Random or non-random contacts between specific cell types were analyzed by means of graph theory. For analysis, thymus blocks were sectioned serially and, then, thymus cells were categorized into types, based on morphological criteria. The distribution of individual cell types within the cortex, cortico-medullary zone and medulla was presented in form of a map. In the analysis, three types of epithelial cell, characteristic of each thymus zone, macrophages, Langerhans-like cells and lymphocytes were found in non-random relations to one another. Moreover, characteristic groups of cells associated with one another were also demonstrated.This study was supported by the Polish Academy of Sciences 相似文献
984.
Lebecka Renata Kistowski Michał Dębski Janusz Szajko Katarzyna Murawska Zofia Marczewski Waldemar 《Plant and Soil》2019,441(1-2):317-329
Plant and Soil - This study aims the detection of proteins associated with increased resistance of tubers to necrotrophic bacteria Dickeya solani in tetraploid and diploid potato plants.... 相似文献
985.
Leslie Chvez‐Galn Jhacqueline Illescas‐Eugenio Magaly Alvarez‐Sekely Renata Baez‐Saldaa Raúl Chvez Ricardo Lascurain 《Microbiology and immunology》2019,63(8):316-327
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) and remains a major cause of morbidity and mortality worldwide. In the host's immune response system, T cells play a critical role in mediating protection against Mtb infection, but the role of CD8+ T cells is still controversial. We evaluated the phenotypical characterization and cytotoxic ability of CD8+ T cells by flow cytometry‐based assay. Cytokine levels in serum were measured by multiplex cytokine assay. Our data show that cells from TB patients have an increased percentage of peripheral blood CD8+αβ+ T (p = 0.02) and CD56+CD8+ T (p = 0.02) and a decreased frequency of NKG2D+CD8+ T (p = 0.02) compared with healthy donors. Unlike CD8+ T cells from healthy donors, CD8+ T cells from TB patients exhibit greater cytotoxicity, mediated by HLA class I molecules, on autologous monocytes in the presence of mycobacterial antigens (p = 0.005). Finally, TB patients have a proinflammatory profile characterized by serum high level of TNF‐α (p = 0.02) and IL‐8 (p = 0.0001), but, interestingly, IL‐4 (p = 0.002) was also increased compared with healthy donors. Our data show evidence regarding the highly cytotoxic status of CD8+ T cells in Mtb infection. These cytotoxic cells restricted to HLA‐A, B, and C could be used to optimize strategies for designing new TB vaccines or for identifying markers of disease progression. 相似文献
986.
Bianca de Sousa Rangel Douglas de Castro Ribeiro Jumma M. A. Chagas Lucas Spada Renata G. Moreira Cristiéle da Silva Ribeiro 《Journal of fish biology》2020,97(2):546-551
Elasmobranchs are particularly vulnerable to overexploitation and population depletion, especially due to their life-history traits, such as low reproductive output and slow growth. Given that capture-induced parturition (abortion or premature birth) is a common consequence of fisheries in elasmobranchs, but still little studied, we investigated how the abortion/premature birth process varies in response to reproductive traits in a freshwater stingray, Potamotrygon amandae. Our results revealed that capture-induced parturition was affected by reproductive traits, such as litter size (one to seven) and gestation stage. The event occurred faster in pregnant females with high litter size during late pregnancy. Also, as found in other elasmobranchs, litter size was positively correlated with maternal size. These findings indicate that larger pregnant females in late pregnancy are more vulnerable to capture-induced parturition. This study improves our understanding of the capture-induced parturition process in stingrays, and provides useful information for management strategies and future recommendations for elasmobranch conservation. 相似文献
987.
988.
989.
Calheiros Ana Carolina Sales Lucas Pedra Maravilha Pereira Netto Annibal Duarte Cavalcanti Diana Negrão Castelar Beatriz Reis Renata Perpetuo 《Journal of applied phycology》2021,33(3):1805-1818
Journal of Applied Phycology - Ulva species have potential uses in several industrial sectors as they are rich in proteins, vitamins, fibers, and minerals. They also produce the essential amino... 相似文献
990.
Josi Maria Zimmermann-Peruzatto Virgínia Meneghini Lazzari Grasiela Agnes Roberta Oriques Becker Ana Carolina de Moura Renata Padilha Guedes Aldo Bolten Lucion Silvana Almeida Márcia Giovenardi 《Cellular and molecular neurobiology》2017,37(5):803-815
Social relations are built and maintained from the interaction among individuals. The oxytocin (OT), vasopressin (VP), estrogen, dopamine, and their receptors are involved in the modulation of sexual behavior in females. This study aimed to analyze the impact of OT gene knockout (OTKO) on sexual behavior and the gene expression of oxytocin (OTR), estrogen alpha (ERα), estrogen beta (ERβ), vasopressin (V1aR), and dopamine (D2R) receptors in the olfactory bulb (OB), prefrontal cortex (PFC), hippocampus (HPC), and hypothalamus (HPT), as well as in the synthesis of VP in the HPT of female mice. Wild-type (WT) littermates were used for comparisons. The CDNAs were synthesized by polymerase chain reaction and the gene expression was calculated with the 2?ΔΔCt formula. Our results showed that the absence of OT caused an increase in the frequency and duration of non-receptive postures and a decrease in receptive postures in the OTKO. OTKO females showed a significant decrease in the gene expression of OTR in the HPC, V1aR in the HPT, and ERα and ERβ in the PFC. There was no significant difference in the gene expression of D2R of OTKO. However, OTKO showed an increased gene expression of V1aR in the HPC. There is no significant difference in VP mRNA synthesis in the HPT between OTKO and WT. Our findings demonstrate that the absence of OT leads to significant changes in the expression of the studied genes (OTR, ERα, ERβ, V1aR), and these changes may contribute to the decreased sexual behavior observed in OTKO females. 相似文献