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101.
102.
A consecutive series of 47 hospitalized cases of Guillain-Barré syndrome seen over a 10-year period was analysed with respect to: (1) age and sex; (2) antecedent events and seasonal distribution; (3) patterns of clinical presentation; (4) CSF and neurophysiological findings; (5) results of treatment with plasma exchange; and (6) outcome. Twenty-two were children, 20 middle-aged and 5 aged; 37 were male and 10 were female. The most frequent antecedent event was upper respiratory tract infections; a seasonal peak incidence was found in winter. Clinical, CSF and neurophysiological findings concurred with those in the Western literature; 79% of the cases were severe. Plasma exchange performed within the first 2 weeks of onset benefitted in the short-term outcome, i.e. improvement by 1 grade at 4 weeks, but the long-term benefit, i.e. the ability to regain independent locomotion, was questionable. Plasma exchange helped in curtailing the time to walking unaided but had no benefit on the duration of artificial ventilation. Factors associated with an adverse outcome were: age over 15 years, severity of motor electrodiagnostic findings (especially a decreased distal CMAP amplitude and EMG signs of acute denervation), requirement for ventilation and slow progression (>3 weeks) to maximum deficit. After a mean follow-up of 11 months, 55% of the patients regained independent locomotion, which is a comparatively low proportion.  相似文献   
103.
104.

Background  

It is generally accepted that genetic factors play a role in susceptibility to both leprosy per se and leprosy type, but only few studies have tempted to quantify this. Estimating the contribution of genetic factors to clustering of leprosy within families is difficult since these persons often share the same environment. The first aim of this study was to test which correlation structure (genetic, household or spatial) gives the best explanation for the distribution of leprosy patients and seropositive persons and second to quantify the role of genetic factors in the occurrence of leprosy and seropositivity.  相似文献   
105.
106.
Although displaying similar amounts of surface IgM and IgD, ECH 408-1 cells only succumb to apoptosis after cross-linking of IgM (not IgD), suggesting that different signaling pathways couple to both receptors. Immunoprecipitation studies revealed the presence of several proteins selectively associated with IgM and IgD, thus ruling out that the lack of inhibitory signaling mediated by IgD might be due to membrane expression in the absence of associated proteins belonging to the B cell receptor complex. 32P metabolic labeling and immunoprecipitation studies demonstrated that IgM and IgD are associated with phosphoproteins of 32-33 kDa in an isotype-specific fashion. Kinetic analyses of tyrosine kinase activity showed that cross-linking of surface IgM or IgD resulted in the rapid (1-3 min) phosphorylation of several protein substrates on tyrosine residues, followed by a dephosphorylation step. Isotype-specific changes of the phosphorylation status specifically affected molecules in the 32-33 kDa range, i.e. IgM (not IgD) cross-linking affected a approximately 32-kDa protein, whereas IgD (not IgM) cross-linking induced phosphorylation of a protein exhibiting a slightly lower mobility (33 kDa). These results suggest that isotype-specific immunoglobulin-associated molecules could be involved in the second messenger cascade leading to different biological effects upon IgM and IgD cross-linking.  相似文献   
107.
Strain UCMJ was isolated from the choana of a jackass penguin (Spheniscus demersus) with recurrent mucocaseous choanal discharge. Isolation of this mycoplasma expands the known range of species hosting mycoplasmas. The name Mycoplasma sphenisci sp. nov. is proposed for this new species, for which strain UCMJ is the type strain.  相似文献   
108.
Mycobacterium ulcerans, the cause of Buruli ulcer, is an environmental mycobacterium with a distinct geographic distribution. The reasons why only some individuals who are exposed to M. ulcerans develop ulcers are not known but are likely to reflect individual differences in the immune response to infections with this bacterium. In this study, we investigated cytokine profiles of peripheral blood mononuclear cells (PBMC) from 23 Buruli ulcer patients and 25 household contacts in a region of Australia where Buruli ulcer is endemic. The results showed that following stimulation with M. ulcerans or Mycobacterium bovis BCG, PBMC from Buruli ulcer patients mounted a Th2-type response, which was manifested by the production of mRNA for interleukin 4 (IL-4), IL-5, IL-6, and IL-10, whereas unaffected contacts responded mainly with the Th1 cytokines gamma interferon (IFN-gamma) and IL-12. For example, mRNA for IL-4 was detected in 18 of 23 patients but in only 3 of 25 control subjects (P < 0.0001). By contrast, PBMC from 21 of 25 unaffected individuals produced IFN-gamma compared with 3 of 23 patients (P < 0.0001). IFN-gamma release following stimulation with mycobacteria was markedly reduced in affected subjects. Frequencies of antibodies to M. ulcerans in serum samples from affected and unaffected subjects were similar, indicating that many of the control subjects had been exposed to this bacterium. Together, these findings suggest that a Th1-type immune response to M. ulcerans may prevent the development of Buruli ulcer in people exposed to M. ulcerans, but a Th-2 response does not.  相似文献   
109.
ABSTRACT

Background

Colorectal cancer (CRC) is considered a major cause of morbidity and mortality in Egypt. Colonoscopy is the standard for detection of lesions. The combination of screening methods is effective. Decrease and loss of DPP-IV/CD26 expression and activity are found in microenvironments of specific tumors which are related to impaired immune functions.  相似文献   
110.
Cenani–Lenz (C–L) syndrome is characterized by oligosyndactyly, metacarpal synostosis, phalangeal disorganization, and other variable facial and systemic features. Most cases are caused by homozygous and compound heterozygous missense and splice mutations of the LRP4 gene. Currently, the syndrome carries one OMIM number (212780). However, C–L syndrome‐like phenotypes as well as other syndactyly disorders with or without metacarpal synostosis/phalangeal disorganization are also known to be associated with specific LRP4 mutations, adenomatous polyposis coli (APC) truncating mutations, genomic rearrangements of the GREM1‐FMN1 locus, as well as FMN1 mutations. Surprisingly, patients with C–L syndrome‐like phenotype caused by APC truncating mutations have no polyposis despite the increased levels of β catenin. The LRP4 and APC proteins act on the WNT (wingless‐type integration site family) canonical pathway, whereas the GREM‐1 and FMN1 proteins act on the bone morphogenetic protein (BMP) pathway. In this review, we discuss the different mutations associated with C–L syndrome, classify its clinical features, review familial adenomatous polyposis caused by truncating APC mutations and compare these mutations to the splicing APC mutation associated with syndactyly, and finally, explore the pathophysiology through a review of the cross talks between the WNT canonical and the BMP antagonistic pathways.  相似文献   
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