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1.

Background  

The fibromyalgia syndrome (FMS) is suggested to be a manifestation of depression or affective spectrum disorder. We measured the cognitive style of patients with FMS to assess personality styles in 44 patients with fibromyalgia syndrome (FMS) by comparing them with 43 patients with major depressive disorder (MDD) and 41 healthy controls (HC).  相似文献   
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B G Stiles 《Toxicon》1991,29(4-5):503-510
A non-radioactive assay was developed for detecting the binding of postsynaptic neurotoxins to acetylcholine receptor (AchR) from Torpedo californica. Enzyme linked immunosorbent assay (ELISA) wells coated with long or short chain neurotoxins specifically bound to purified AchR while crotamine or two different cardiotoxins did not. Bound receptor was detected by antibody against AchR. Specificity was determined by dose-response experiments and competition studies using carbamylcholine chloride, acetylcholine chloride, or Naja naja atra cobrotoxin mixed with receptor.  相似文献   
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Long-term outcome and complications of children born with meningomyelocele   总被引:9,自引:1,他引:8  
The long-term functional outcome of 101 children born with meningomyelocele between 1971 and 1981 was assessed, by a combination of retrospective chart review and follow-up assessments. The children had been managed at birth using a process ofnonstandardized selection. Eighty-three of the 101 patients survived after a minimum follow-up of 8.6 years, for a mortality rate of 18%. Forty-four of 83 children (53%) were community ambulators, and this correlated well with the presence of intact quadriceps function. Forty-eight children (58%) attended normal school and were grade-appropriate. Sixty-two of 83 patients (75%) were socially continent of urine, and 71/83 (86%) were socially continent of stool. Hydrocephalus was present in 93 of the 101 children in the study, and 85 children were shunted. Half of the shunted children required a shunt revision in the first year of life, and thereafter the rate of revision decreased, so that after 2 years the risk of revision was approximately 10% per year.  相似文献   
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The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions.  相似文献   
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Clostridium spiroforme iotalike toxin produced time- and concentration-dependent incorporation of ADP-ribose into homo-poly-L-arginine. Polyasparagine, polyglutamic acid, polylysine, and agmatine were poor substrates. Enzyme activity was associated with the light-chain polypeptide of the toxin. The heavy chain did not possess ADP-ribosyltransferase activity, nor did it enhance or inhibit activity of the light chain. In broken-cell assays, the toxin acted mainly on G-actin, rather than F-actin. A single ADP-ribose group was transferred to each substrate molecule (G-actin). The enzyme was heat sensitive, had a pH optimum in the range of 7 to 8, was inhibited by high concentrations of nicotinamide, and was reversibly denatured by urea and guanidine. Physiological levels of nucleotides (AMP, ADP, ATP, and ADP-ribose) and cations (Na+, K+, Ca2+, and Mg2+) were not very active as enzyme inhibitors. The toxin was structurally and functionally similar to Clostridium botulinum type C2 toxin and Clostridium perfringens iota toxin. When combined with previous findings, the data suggest that a new class of mono(ADP-ribosyl)ating toxins has been found and that these agents belong to a related and possibly homologous series of binary toxins.  相似文献   
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Clostridium perfringens iota-toxin consists of two separate proteins identified as a cell binding protein, iota b (Ib), which forms high-molecular-weight complexes on cells generating Na(+)/K(+)-permeable pores through which iota a (Ia), an ADP-ribosyltransferase, presumably enters the cytosol. Identity of the cell receptor and membrane domains involved in Ib binding, oligomer formation, and internalization is currently unknown. In this study, Vero (toxin-sensitive) and MRC-5 (toxin-resistant) cells were incubated with Ib, after which detergent-resistant membrane microdomains (DRMs) were extracted with cold Triton X-100. Western blotting revealed that Ib oligomers localized in DRMs extracted from Vero, but not MRC-5, cells while monomeric Ib was detected in the detergent-soluble fractions of both cell types. The Ib protoxin, previously shown to bind Vero cells but not form oligomers or induce cytotoxicity, was detected only in the soluble fractions. Vero cells pretreated with phosphatidylinositol-specific phospholipase C before addition of Ib indicated that glycosylphosphatidyl inositol-anchored proteins were minimally involved in Ib binding or oligomer formation. While pretreatment of Vero cells with filipin (which sequesters cholesterol) had no effect, methyl-beta-cyclodextrin (which extracts cholesterol) reduced Ib binding and oligomer formation and delayed iota-toxin cytotoxicity. These studies showed that iota-toxin exploits DRMs for oligomer formation to intoxicate cells.  相似文献   
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