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51.
Lymphoblastoid cell lines from patients with xeroderma pigmentosum (2 forms) and progeria (unusual form) were established using transformation of peripheral blood lymphocytes by Epstein--Barr virus. The influence of different UV doses on cell vitality, proliferation and cell cycle progression was studied by means of flow cytometry. The cell vitality was determined after incubation of cells with etidium bromide and FDA. We used cytograms with two logarithmic signals (log green/log red) to discriminate the cell cycle status. Cell cultures were used with density of 500,000 cells per 1 ml, previously synchronized at G-phase by the incubation in a medium with low serum content. The effect of UV irradiation was followed during 72 h. Among four analysed cell lines only line XP2SP demonstrated enhanced UV sensitivity, expressed by decreasing of the amount of living cells after the UV dose of 2.5 J/m2 and higher. The cell cycle studies showed that cells were blocked in S-phase and simultaneously the amount of apoptotic cells with both reduced DNA content and ability to bind FDA was seen increased. Similar events were observed in the control line only after the dose of 20 J/m2 and higher.  相似文献   
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Volatile anaesthetics have historically been considered to act in a nonspecific manner on the central nervous system. More recent studies, however, have revealed that the receptors for inhibitory neurotransmitters such as gamma-aminobutyric acid (GABA) and glycine are sensitive to clinically relevant concentrations of inhaled anaesthetics. The function of GABA(A) and glycine receptors is enhanced by a number of anaesthetics and alcohols, whereas activity of the related GABA rho1 receptor is reduced. We have used this difference in pharmacology to investigate the molecular basis for modulation of these receptors by anaesthetics and alcohols. By using chimaeric receptor constructs, we have identified a region of 45 amino-acid residues that is both necessary and sufficient for the enhancement of receptor function. Within this region, two specific amino-acid residues in transmembrane domains 2 and 3 are critical for allosteric modulation of both GABA(A) and glycine receptors by alcohols and two volatile anaesthetics. These observations support the idea that anaesthetics exert a specific effect on these ion-channel proteins, and allow for the future testing of specific hypotheses of the action of anaesthetics.  相似文献   
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A study was made into the functional status of hypophysis, adrenal cortex, ovaries, and thyroid gland in patients with kraurosis and leukoplakia vulvae. The above patients demonstrated profound disturbances in the system hypophysis-ovaries, that attest to the need for applying corrective therapies to treat the disturbed hormonal homeostasis.  相似文献   
56.
Evidence from several central nervous system (CNS) inflammatory disease models suggests that intrathecal complement synthesis may contribute to early inflammatory events in the brain. In this study, we examined the expression of the receptor for C5a (C5aR), a potent inflammatory and chemotactic factor, in the brains of transgenic mice with constitutive astrocyte expression of interleukin-3 (IL-3), a hematopoietic and immunomodulatory cytokine. By in situ hybridization, we demonstrated that cells infiltrating the cerebellar meninges, the cerebellum, and demyelinating lesions in the cerebellum were strongly positive for C5aR mRNA. By immunohistochemistry, the infiltrating cells expressing the C5aR were identified as macrophages based on staining with antibodies to the complement receptor type 3 and F4/80, a mouse macrophage-specific marker. In addition, some of the cells in cerebellar lesions were positive for the astrocyte-specific marker, glial fibrillary acidic protein, suggesting that a subpopulation of astrocytes in these lesions express elevated levels of the C5aR. Increased C5aR expression was also observed in cortical neurons in the occipital cortex and in pyramidal neurons in the cornu ammonis and subiculum of the hippocampus, at both the protein and mRNA levels. These data suggest that IL-3 may play an immunomodulatory role in C5aR expression on several cell types in the brain and that increased C5aR expression correlates with the pathology seen in this model. The transgenic mice used in this study provide a useful tool for characterizing the mechanism of regulation of the C5aR expression and for examining the functions of this chemotactic receptor in CNS inflammation.  相似文献   
57.
Free-flow electrophoresis (FFE) has been applied to the separation and purification of a variety of proteins and polypeptides: bee venom, tumor necrosis factor, interleukin-1beta, interferon-gamma and superoxide dismutase. FFE at constant pH and conductivity of the carrying buffer is shown to be efficient at various separation schemes. In some cases, the method allows us to obtain proteins with a purity of more than 90% at a productivity of 20-30 mg/h. An electrophoretic apparatus with a new, multi-sectional construction of the electrophoretic chamber and a system for cross-displacement of carrying buffer in the chamber is described.  相似文献   
58.
A method for determining whether structures distributed along a cell's membrane represent a random spatial distribution is presented in this paper. Two three-dimensional (3-D) images are acquired from one cell by wide-field digital imaging of cells which have been labeled with two different fluorescent antibodies. Prior to spatial analysis, a constrained regularized least squares restoration of the images is performed. This is followed by registration via fiducial markers (dual-labeled beads). A deformable model is then used to map data near the surface to the surface. Finally, each resulting data set is analyzed to determine whether it is spatially random. To do this, we generalize the test for complete spatial randomness of points in a plane, to test voxels distributed along a voxelized membrane in three dimensions. We also test whether the distribution of one protein is independent of the distribution of a second protein. The method is applied to compare the distribution of the protein kinase C to that of vinculin. Vinculin is a protein which anchors intracellular filaments to the cell's plasma membrane. It is also used as a (sparse) membrane marker for the deformable model. Protein kinase C facilitates molecular motors inside the cell. These may be associated with actin and myosin filaments.  相似文献   
59.
Skating is a favourite sport in the Netherlands. Injury data on skating were collected from the emergency departments of 6 hospitals in the province of Friesland in the Netherlands during the Eleven Cities ice skating marathon over 200 kilometers in January 1997, with 16,688 participants. Among a total of 55 fractures, the maxillofacial skeleton had a relative high fracture frequency (n = 7; 13%), especially the zygomatic complex (n = 6); one patient had a mandibular fracture. An innocent-looking black eye, unilateral numbness of the upper lip and malocclusion following a skating accident merit full medical attention.  相似文献   
60.
The paper analyzes the standard legal and methodological assurance of the quality and safety of animal food raw materials and foodstuffs (meat, meat products, fish, shellfish, crayfish and their processing products) by the parasitic purity rates according the requirements under the Russian Federation's laws "On Sanitary and Epidemiological Well-Being of the Population", "On Protection of Consumer's Rights", "On Certification of Products and Services", those of SanPiN, such as 2.3.2.560-96 "Sanitary Requirements for the Quality and Safety of Food Raw Materials and Foodstuffs" and 3.2.569-96 "Prevention of Parasitic Diseases in the Russian Federation".  相似文献   
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