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HLA and Gm typing were carried out in 16 families. Seven families included 10 sib pairs with rheumatoid arthritis (RA) and autoimmune thyroid disease (ATD) respectively, and nine families included 16 sib pairs with RA and circulating thyroid autoantibodies respectively. Eight, 11, and seven sib pairs with either RA or clinical or immunological evidence of ATD shared none, one, and two HLA haplotypes respectively, and two, seven, and two informative sib pairs shared none, one, and two Gm haplotypes respectively. This random haplotype sharing of HLA and Gm haplotypes suggests that non-HLA, non-Gm linked genes are likely to be involved in any genetic predisposition common to RA and ATD.  相似文献   
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Magnetic Resonance Diffusion Tensor Imaging (DTI) of the control and traumatic injured spinal cord of a rat in vitro is reported. Experiments were performed on excised spinal cords from 10 Wistar rats, using a home-built 6.4 T MR microscope. MRI and histopathological results were compared. Presented results show that DTI of the spinal cord, perfused with formalin 10 minutes after the injury, can detect changes in water diffusion in white matter (WM) and in gray matter (GM), in areas extending well beyond the region of direct impact. Histology of neurons of the GM shows changes that can be attributed to ischemia. This is in agreement with the observed decrease of diffusion in the injured regions, which may be attributed to the cytotoxic edema due to ischemia. However, the diffusion changes in highly anisotropic WM seem to be caused by a direct action of mechanical force of impact, which significantly distorts the nerve fibers.  相似文献   
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Many data suggest involvement of inflammation in neurodegeneration. However, the exact mechanisms of this cooperation are poorly understood. We have previously shown that induction of inflammatory reaction, both before and after injury of the striatum, affects regeneration of dopaminergic neurons. In the present research we studied the role of inflammatory reaction in non-injured striatum. We used myelin oligodendrocyte glycoprotein (MOG) 35-55 in complete Freund's adjuvant (CFA) to elicit experimental autoimmune encephalomyelitis (EAE) mice model. As determined by HPLC, striatal dopamine (DA) and serotonin levels in mice treated with either MOG 35-55 in CFA or CFA alone were significantly higher compared to vehicle-treated controls on 13th day after induction. The ratio of homovanilic acid/dopamine (HVA/DA) and 3, 4 dihydroxyphenylacetic acid/dopamine (DOPAC/DA) were significantly lower in the MOG and CFA groups on 13th day, indicating decreased DA metabolism. Noradrenaline (NA) concentration did not differ between groups. Moreover, the striatal mRNA IL-1beta and TNF-alpha levels were elevated during induction phase of EAE in both groups, as determined by RT-PCR. Our data indicate regulatory connection between dopaminergic and immune systems.  相似文献   
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The telechelics 1 from methyl methacrylate and 1,1,2,2-tetraphenyl-1,2-diphenoxyethane, can be separated by adsorption chromatography. The structure of the dimers and trimers was identified by 1H NMR-spectroscopy. The free radical oligomerization is a process in which the syndiotactic structure is favoured above the isotactic one.  相似文献   
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Medical genetic histories of 165 children with primary central nervous system (CNS) tumours and 4599 relatives of these probands were examined to identify birth defects or genetic disorders that may be associated with the aetiology of CNS tumours. Twelve primary malignancies were found in 329 (4%) of the parents of probands. Two of 99 half sibs but no full sibs had malignancies. Twenty-four percent of families had histories warranting consultation for an inherited disorder or birth defect. Single instances of malformations or genetic disorders were reported in 36 families and several disorders were reported in more than one family, including familial hypercholesterolaemia (4), olivopontocerebellar atrophy (2), and familial abdominal aortic aneurysm (2). Although recurring abnormalities were not identified in probands, it is possible that one or more of the birth defects or genetic disorders observed in probands or relatives may be associated with CNS tumourigenesis.  相似文献   
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Summary Varying host reaction of the house fly, Musca domestica L., to parasitism by the braconid Aphaereta pallipes (Say) was chiefly correlated with the diet of the host. Some evidence was found that implicated the strain of the host, the rearing temperatures, the ages of the parasitoid and the host, and the site of oviposition. Though development of A. pallipes embryos was inhibited before they became encapsulated with melanin within the host, the presence of the parasitoid and (or) the effect of its paralyzing toxin that was injected into the host just before oviposition prevented normal larval, pupal, or adult development of the six house fly strains tested. A considerable increase of parasitoid survival occurred when M. domestica larvae were reared on a chemically defined diet.
Zusammenfassung Musca domestica L. reagierte unterschiedlich auf die Parasitierung durch die Braconide Aphaereta pallipes (Say). Die verschiedenen Reaktionen waren im wesentlichen mit der Art der Wirtsnahrung korreliert. Daneben finden sich Hinweise, daß auch der Wirtsstamm, dessen Zuchttemperatur, das Alter von Parasit und Wirt und der Eiablageort des Parasiten die Reaktionen beeinflussen. Obgleich die Entwicklung von Parasitenembryonen bereits gehemmt war, ehe sie innerhalb des Wirtes von Melanin eingeschlossen wurden, so verhinderten doch die Parasiten-embryonen und/oder die Wirkung der vor der Eiablage abgegebenen Paralysierungstoxine die normale Entwicklung der Wirte aus sechs Fliegenstämmen. Eine beträchtliche Steigerung der Überlebensrate der Parasiten trat ein, wenn M. domestica-Larven in einem Gemisch chemisch genau definierter Nahrung gezogen wurden.


With 8 Figures in the Text

Formerly National Research Council Postdoctorate Fellow, Research Institute, Belleville, Ontario.  相似文献   
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