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51.
BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis.  相似文献   
52.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
53.
We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1‐negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society  相似文献   
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Influenza A was cultured in 62 double rooms. The roommate was infected in 12 (19.4%). During 3,294 resident-seasons, influenza was cultured in 208 single rooms (6.3%). Those who lived in double rooms with a culture-positive roommate had a 3.07 relative risk (CI95, 1.61-5.78) of acquiring influenza.  相似文献   
56.
A new decontaminated hassles measure for adults, the Survey of Recent Life Experiences, was developed and validated. An initial pool of 92 items was administered to 100 subjects along with the Perceived Stress Scale. Fifty-one items were selected, based on significant correlations with the latter scale. The alpha reliability of the resultant final form of the Survey of Recent Life Experiences and its correlation with perceived stress were both high. In a separate cross-replication sample of 136 adults, the alpha reliability of the Survey and its correlation against the Perceived Stress Scale remained acceptably high. Moreover, separate-sex analyses supported the reliability and validity of the Survey of Recent Life Experiences across gender. Factor analysis of the Survey yielded six interpretable factors. Intercorrelations among subscales based on these factors were generally modest, suggesting that the scale is relatively free from contamination by psychological distress.The work reported was facilitated by a grant from the Social Sciences and Humanities Research Council of Canada's Small Grant Program, administered by the Office of Research Administration, York University. The authors appreciate the cooperation of staff at the Ontario Science Centre, Toronto, and the assistance of Maria Gurevich in verifying the data.  相似文献   
57.
The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage.  相似文献   
58.
Proteases that reduce insulin-like growth factor binding protein-3 affinity for insulin-like growth factor-I have been found in various biological fluids from human beings and rats. The aim of this study was to assess the local and systemic role of insulin-like growth factor binding protein-3 proteases in the course of wound healing. Six rats had polyvinyl alcohol sponges implanted subcutaneously. Wound fluid and serum were collected 3 days after wounding. Gel filtration experiments showed that insulin-like growth factor-I was present as a 150 kDa complex in both serum and wound fluid. However, insulin-like growth factor binding protein-3 measured by Western ligand blotting was virtually absent in wound fluid. Co-incubation of serum and wound fluid resulted in an ethylenediamine tetraacetic acid-inhibitable degradation of serum insulin-like growth factor binding protein-3, suggesting the presence of an insulin-like growth factor binding protein-3 degrading activity in wound fluid. Incubation of ((125)I)-labeled insulin-like growth factor binding protein-3 in wound fluid and serum showed a rapid and time-dependent proteolysis of insulin-like growth factor binding protein-3 in wound fluid with metabolites similar to those generated by human term pregnant serum. No sign of insulin-like growth factor binding protein-3 degrading activity was observed in rat-serum. In conclusion, there is an insulin-like growth factor binding protein-3 proteolytic activity in wound fluid, and it is hypothesized that this activity results in a localized increase in insulin-like growth factor-I bioactivity.  相似文献   
59.
C2H2-type zinc finger genes comprise one of the largest genefamilies in the human genome. These proteins are involved ingenetic regulation and development and are quite conserved throughoutevolution. The finger domains commonly contain the small linkerpeptide TGEKP between some finger units. Here, we report theisolation of 133 human zinc finger cDNAs, of which 118 are novel.These clones were isolated from human brain cDNA libraries usingoligonucleotide hybridization followed by expressed sequencetag (EST) analysis, sequencing from the conserved linker regionusing degenerate oligonucleotide primers. This directed partialsequencing approach to cDNA isolation and characterization,signature sequencing, combines the speed of EST automatic sequencingwith the focus of specific cDNA family analysis. Signature sequencingminimizes the generation of less informative random EST sequencesand provides a unique relative position for sequence comparison.We also show that there is an even distribution of these RNA5from this brain cDNA library, and that these cDNAs contain N-terminaldomains found in other zinc finger genes. This rapid focusedsequencing approach should be applicable to any family of cDNAscontaining short conserved signature peptide sequences.  相似文献   
60.
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