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51.
烟青虫核型多角体病毒的复制和染病后血淋巴蛋白的变化 总被引:4,自引:0,他引:4
用烟青虫(Hiliothis assulta)核型多角体病毒感染5龄初烟青虫幼虫,以染病后24、48·,72、96/120小时分别测定了虫体血淋巴蛋白浓度的变化。幼虫染病后24小时血淋巴蛋白浓度要高于同期对照组,72小时后染病幼虫血淋巴蛋白浓度较对照急剧下降。在染病及对照血淋巴样品中电泳分析(PAGE)三种蛋白(普通蛋白、糖蛋白和脂蛋白)均可分别染出22条、3条和3条带。分析结果表明,在虫体正常生长代谢过程中发生变化的主要蛋白可能大多为糖脂复合蛋白,但病毒的侵染能抑制这些变化的产生。电镜观察染病毒后幼虫的中肠组织和气管上皮组织,发现中肠染病轻微,不形成多角体。气管上皮细胞感染情况表明其属于对NPV感染较为敏感的组织之一,并在虫体染病后的病毒二次感染上可能起着重要作用。 相似文献
52.
Olga V. Krupnik Natalia V. Fadeeva Nina P. Kvitko Valerii A. Shepelev Peter E. Nielsen Yurii S. Lazurkin 《Journal of biomolecular structure & dynamics》2013,31(4):503-512
Abstract Structurally isomeric complexes formed between homopyrimidine bis-PNAs (T2JT2JT4-linker-T4CT2CT2) and single- and double-stranded DNA targets were investigated. These complexes are triplexes designated S1, S2 and S3 in order of increased mobility by polyacrylamide gel electrophoresis. It is shown that the S3 isomer is formed only on double-stranded DNA and possesses highest stability. Isomers S2 and S1 are formed upon binding of bis-PNA to double-stranded as well as to single-stranded DNA. It was found that the stability of the isomer S1 increases dramatically in the presence of excess single-stranded oligonucleotide complementary to the bis-PNA. The structure of the stabilized S1 isomer is proposed to consist of two bis-PNA/DNA triplexes. The relationship between the yield of the isomer S1 formed on single-stranded DNA and the bis-PNA concentration was investigated and a kinetic model of the formation of S1 is presented. 相似文献
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55.
Polina D. Kotova Veronika Yu. Sysoeva Olga A. Rogachevskaja Marina F. Bystrova Alisa S. Kolesnikova Pyotr A. Tyurin-Kuzmin Julia I. Fadeeva Vsevolod A. Tkachuk Stanislav S. Kolesnikov 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
Cultured mesenchymal stromal cells (MSCs) from different sources represent a heterogeneous population of proliferating non-differentiated cells that contains multipotent stem cells capable of originating a variety of mesenchymal cell lineages. Despite tremendous progress in MSC biology spurred by their therapeutic potential, current knowledge on receptor and signaling systems of MSCs is mediocre. Here we isolated MSCs from the human adipose tissue and assayed their responsivity to GPCR agonists with Ca2 + imaging. As a whole, a MSC population exhibited functional heterogeneity. Although a variety of first messengers was capable of stimulating Ca2+ signaling in MSCs, only a relatively small group of cells was specifically responsive to the particular GPCR agonist, including noradrenaline. RT-PCR and immunocytochemistry revealed expression of α1B-, α2A-, and β2-adrenoreceptors in MSCs. Their sensitivity to subtype-specific adrenergic agonists/antagonists and certain inhibitors of Ca2+ signaling indicated that largely the α2A-isoform coupled to PLC endowed MSCs with sensitivity to noradrenaline. The all-or-nothing dose-dependence was characteristic of responsivity of robust adrenergic MSCs. Noradrenaline never elicited small or intermediate responses but initiated large and quite similar Ca2+ transients at all concentrations above the threshold. The inhibitory analysis and Ca2+ uncaging implicated Ca2+-induced Ca2+ release (CICR) in shaping Ca2+ signals elicited by noradrenaline. Evidence favored IP3 receptors as predominantly responsible for CICR. Based on the overall findings, we inferred that adrenergic transduction in MSCs includes two fundamentally different stages: noradrenaline initially triggers a local and relatively small Ca2+ signal, which next stimulates CICR, thereby being converted into a global Ca2+ signal. 相似文献
56.
It was found using the model of subcutaneous implantation in rats that the calcification of the aorta wall occurs by two mechanisms of which one is dependent on, and the other independent of the migration of recipient cells to the transplant. 相似文献
57.
Carolyn TA Herzig Ray W Waters Cynthia L Baldwin Janice C Telfer 《BMC evolutionary biology》2010,10(1):181
Background
The scavenger receptor cysteine rich (SRCR) domain is an ancient and conserved protein domain. CD163 and WC1 molecules are classed together as group B SRCR superfamily members, along with Spα, CD5 and CD6, all of which are expressed by immune system cells. There are three known types of CD163 molecules in mammals, CD163A (M130, coded for by CD163), CD163b (M160, coded for by CD163L1) and CD163c-α (CD163L1 or SCART), while their nearest relative, WC1, is encoded by a multigene family so far identified in the artiodactyl species of cattle, sheep, and pigs. 相似文献58.
Expression of elements of apomixis was studied for ten seasons in sorghum line AS-la and its backcross hybrids on the 9E and A3 sterile cytoplasms. Cytoembryological analysis revealed aposporous embryo sacks (apo-ESs), their initial cells, and, rare, parthenogeneic proembryos in ovules of line AS-la and its BC2 and BC3 hybrids on the 9E cytoplasm. The A3 sterile cytoplasm suppressed the development of parthenogenetic proembryos, but did not affect the apo-ES formation. The frequency of apomictic elements increased in seasons with high daily temperatures and total precipitation deficiency in the period when the ovule and megagametophyte developed (r = -0.805, P < 0.01). Selection was used to isolate the families where the frequency of ovules with apo-ESs was 28% and the frequency of parthenogenetic proembryos was 14%. Emasculated panicles of line AS-la were pollinated with pollen of line Volzhskoe-4v, which carried the Rs marker dominant gene, responsible for the anthocyan color of coleoptyles and leaves in seedlings. Plants of the maternal type were found in the progenies of these crosses at a frequency of 1.4-28.1%. The genetic structure of the endosperm in grains with maternal-type seedlings was inferred from the electrophoretic patterns of storage proteins (kafirins). The kafirin spectra of grains producing maternal-type seedlings was similar to the spectrum of line AS-la and differed from the spectra of grains producing hybrid seedlings, indicating that the endosperm developed independently when apomictic grains formed in line AS-1a. The results showed that lines with facultative apomixis can be constructed in functionally diploid plants. 相似文献
59.
Arutiunov NV Konovalov NA Mel'nikova-Pitskheluri TV Fadeeva LM Tissen TP 《Vestnik rentgenologii i radiologii》2011,(2):41-46
For many decades X-ray myelography has remained one of the major diagnostic methods for spinal pathology. With the advent of computed tomography (CT), CT myelography using water-soluble contrast agents has been developed. Visualization of the subarachnoidal spaces of the spinal cord and dural sac without an intrathecal contrast agent has become possible with the emergence of magnetic resonance imaging (MRI). Its further development and improvement has brought to existence the new noninvasive technique MR myelography based on the suppression of a signal from the medulla and its enhancement from the cerebrospinal fluid-containing spaces. This paper compares routine X-ray myelography, CT myelography, and MR myelography used in the diagnosis of lumbosacral intervertebral disk herniation and assesses the informative value and benefits of MR myelography as a noninvasive diagnostic method for this pathology. 相似文献
60.
Expression of elements of apomixis was studied for ten seasons in sorghum line AS-1a and its backcross hybrids in the 9E and
A3 sterile cytoplasms. Cytoembryological analysis revealed aposporous embryo sacks (apo-ESs), their initial cells, and, rare,
parthenogeneic proembryos in ovules of line AS-1a and its BC2 and BC3 hybrids on the 9E cytoplasm. The A3 sterile cytoplasm suppressed the development of parthenogenetic proembryos, but did not
affect the apo-ES formation. The frequency of apomictic elements increased in seasons with high daily temperatures and total
precipitation deficiency in the period of ovule and megagametophyte development (r = −0.805, p <.01). Selection was used to isolate the families where the frequency of ovules with apo-ESs was 28% and the frequency of
parthenogenetic proembryos was 14%. Emasculated panicles of line AS-1a were pollinated with pollen of line Volzhskoe-4v, which
carried the Rs marker dominant gene, responsible for the anthocyan color of coleoptyles and leaves in seedlings. Plants of the maternal
type were found in the progenies of these crosses at a frequency of 1.4–28.1%. The genetic structure of the endosperm in grains
with maternal-type seedlings was inferred from the electrophoretic patterns of storage proteins (kafirins). The kafirin spectra
of grains producing maternal-type seedlings was similar to the spectrum of line AS-1a and differed from the spectra of grains
producing hybrid seedlings, indicating that the endosperm developed autonomously when apomictic grains formed in line AS-1a.
The results showed that lines with facultative apomixis can be constructed in functionally diploid plants. 相似文献