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81.
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
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83.
Walsh DM Fadeeva JV LaVoie MJ Paliga K Eggert S Kimberly WT Wasco W Selkoe DJ 《Biochemistry》2003,42(22):6664-6673
Regulated intramembrane proteolysis (RIP) of the amyloid precursor protein (APP) produces amyloid beta-protein (Abeta), the probable causative agent of Alzheimer's disease (AD), and is therefore an important target for therapeutic intervention. However, there is a burgeoning consensus that gamma-secretase, one of the proteases that generates Abeta, is also critical for the signal transduction of APP and a growing list of other receptors. APP is a member of a gene family that includes two amyloid precursor-like proteins, APLP1 and APLP2. Although APP and the APLPs undergo similar proteolytic processing, there is little information about the role of their gamma-secretase-generated intracellular domains (ICDs). Here, we show that APLP1 and 2 undergo presenilin-dependent RIP similar to APP, resulting in the release of a approximately 6 kDa ICD for each protein. Each of the ICDs are degraded by an insulin degrading enzyme-like activity, but they can be stabilized by members of the FE65 family and translocate to the nucleus. Given that modulation of APP processing is a therapeutic target and that the APLPs are processed in a manner similar to APP, any strategy aimed at altering APP proteolysis will have to take into account possible effects on signaling by APLP 1 and 2. 相似文献
84.
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
85.
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
86.
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
87.
88.
The ultrastructure of liver cells was studied in rooks (Corvus frugilegus) living in radioactive and chemical contamination areas. The ultrastructure of liver cells from rook as well as jackdaw (Corvus monedula) and hooded crow (Corvus cornix) (Corvidae family) from a conventionally clean area was studied as control. Control hepatocytes proved to contain a great number of mitochondria, many of which were swollen and had clear matrix and disorganized cristae. The cristae nearly lacked glycogen and had abundant lipid droplets, which often tightly contacted mitochondria. The cytoplasm of hepatocytes in birds from both ecologically unfavorable areas had numerous mitochondria with the same ultrastructure. In contrast to control, the hepatocyte cytoplasm: (1) contained a lot of glycogen; (2) there were many lipid droplets, which directly contacted glycogen granules; and (3) had more abundant peroxisomes. In addition to normal erythrocytes, the sinusoids contained erythrocytes with mitochondria, vesicles, and lipid droplets in their cytoplasm. Analysis of many micrographs of lipid droplets contacting glycogen granules, mitochondria, peroxisomes, and cisterns of smooth endoplasmic reticulum allowed us to propose that glycogen is synthesized via gluconeogenesis from glycerol and products of fatty acid oxidation in the liver cell cytoplasm of rooks from ecologically unfavorable areas as distinct from control. 相似文献
89.
Dioxidine++-induced changes were shown to occur in the protein composition of the cells of Staphylococcus aureus. The most significant damages were observed in the composition of exoproteins. Dioxidine++ had a specific inhibitory effect on intracellular nuclease, which was accompanied by a decrease in virulence and disorders in the toxin formation. 相似文献
90.
Mark TA Donoghue Channa Keshavaiah Sandesh H Swamidatta Charles Spillane 《BMC evolutionary biology》2011,11(1):47