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81.
AP Colombo C Eftimiadi AD Haffajee MA Cugini SS Socransky 《Canadian Metallurgical Quarterly》1998,25(6):465-474
The purpose of this investigation was to compare the levels of serum IgG2, the frequency of detection of Gm(23)-negative allotype and frequency of detection of FcgammaRIIa and FcgammaRIIIb receptor haplotypes in 32 refractory, 54 successfully treated and 27 periodontally healthy individuals. Refractory subjects showed mean full mouth attachment loss and/or >3 sites with attachment loss >2.5 mm within 1 year after both scaling and root planing, and surgery plus systemically administered tetracycline. Successfully treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm 1 year post-therapy. Periodontally healthy subjects exhibited no pocket depth or attachment level >3 mm, and no evidence of progressing disease during 1 year of monitoring. Blood was obtained from each subject at baseline. Serum IgG2 and Gm(23) allotype were determined using radial immunodiffusion. DNA was extracted from whole blood and the FcgammaR genotypes determined using PCR and allele specific oligonucleotide probes. Significance of differences among clinical groups were sought using the Kruskal-Wallis or chi-square tests. Associations between 2 or more variables were tested using regression analysis. Refractory subjects exhibited higher mean attachment loss and pocket depth than successfully treated or periodontally healthy subjects. Smoking status did not differ significantly among groups. No significant differences in serum IgG2 levels and frequency of detection of Gm(23)-negative allotype were observed among the clinical groups. Serum IgG2 level was positively associated with the number of serum antibody responses to subgingival species (r=0.51, p<0.001). Subjects with the Gm(23)-negative allotype exhibited lower mean levels of serum IgG2 (3.06+/-0.3 versus 3.9+/-0.2, p<0.01) and mean number of serum antibodies to subgingival species (17.7+/-1.7 versus 23.3+/-1.4, p<0.05) than allotype positive individuals. No significant differences in FcgammaR haplotype distribution were observed among the 3 clinical groups. Associations of serum IgG2 level, Gm(23) allotype, FcgammaRIIa and FcgammaRIIIb receptor haplotypes and smoking status were weakly related or not related to clinical status. This lack of relationship may have been due to a reality of no relationship, or the inadvertent pooling of subjects where these factors were of primary importance with subjects in whom these factors played a less important role. 相似文献
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OBJECTIVE AND IMPORTANCE: We report a unique case of ivory osteoma of the cervical spine. CLINICAL PRESENTATION: The clinical presentation was one of polyradicular deficit without myelopathy after trauma. The imaging characteristics and histology of the lesion were those of a classic ivory osteoma. INTERVENTION: A complete surgical excision of the lesion was accomplished. CONCLUSION: We think we have recorded the only well-documented case of ivory osteoma affecting the spine. 相似文献
84.
Determination of the epitope of an inhibitory antibody to proliferating cell nuclear antigen 总被引:1,自引:0,他引:1
G Roos Y Jiang G Landberg NH Nielsen P Zhang MY Lee 《Canadian Metallurgical Quarterly》1996,226(1):208-213
We identified an expansion of the CAG trinucleotide repeat in the coding region of the Machado-Joseph disease gene in 7 of 24 American families diagnosed with autosomal dominant ataxia. All affected individuals were heterozygous for an expanded allele that ranged from 67 to more than 200 CAG repeats, whereas the normal allele had 14 to 33 repeats. In contrast to the Azorean-Portuguese origins of Machado-Joseph disease, the two largest American families were of German and Dutch-African descent. Clinical, pathologic, and genetic evaluations suggest that American families with spinocerebellar ataxia type 3 differ from those with Machado-Joseph disease by their ethnic origins, predominant spinopontine atrophy, lack of dystonic features, and larger CAG repeat expansion. 相似文献
85.
SS El-Dahr 《Canadian Metallurgical Quarterly》1998,18(6):633-640
Because many patients present themselves for treatment with both craniofacial and craniocervical pain, 2 questions arise: (1) What are the sensory and motor consequences of dysfunction in either of these areas on the other? (2) Do craniofacial and craniocervical pain have a similar cause? These questions formed the impetus for this review article. The phenomenon of concurrent pain in craniofacial and cervical structures is considered, and clinical reports and opinions are presented regarding theories of cervical-to-craniofacial and craniofacial-to-cervical pain referral. Because pain referral between these 2 areas requires anatomic and functional connectivity between trigeminally and cervically innervated structures, basic neurophysiologic and neuroanatomic literature is reviewed. The published data clearly demonstrate neurophysiologic and structural convergence of cervical sensory and muscle afferent inputs onto trigeminal subnucleus caudalis nociceptive and non-nociceptive neurons. Moreover, changes in metabolic activity and blood flow in the brainstem and cervical dorsal horn of the spinal cord in both monkeys and cats have been demonstrated after electric stimulation of the V1-innervated superior sagittal sinus. In conclusion, the animal experimental data support the findings of human empiric and experimental studies, which suggest that strong connectivity exists between trigeminal and cervical motor and sensory responses. 相似文献
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JW Erdman AJ Thatcher NE Hofmann JD Lederman SS Block CM Lee S Mokady 《Canadian Metallurgical Quarterly》1998,128(11):2009-2013
The algae Dunaliella bardawil and Dunaliella salina naturally contain large concentrations of all-trans and 9-cis beta-carotene (betaC). The purpose of this study was to compare the relative serum and tissue accumulation of all-trans and 9-cis betaC in ferrets fed different ratios of all-trans/9-cis betaC derived from two commercial sources, D. bardawil or D. salina (Betatene). Male ferrets (7 wk old) were fed carotene-free, pelleted diets for 27 d. Beginning on d 18, groups of ferrets (n = 6 or 7) received daily, one of six oral supplements varying in ratios of 9-cis and all-trans betaC mixed with approximately 1.0mL of Ensure. Four supplements containing 5.2-8.3 micromol total betaC were prepared from a 20% Betatene preparation, D. bardawil, a high-cis Betatene preparation, and Betatene further enriched in 9-cis betaC with all-trans betaC/9-cis betaC ratios of 2.2, 1.5, 0.6 and 0.4, respectively. Two control supplements, high and low betaC, were prepared from commercial betaC beadlets. The high control supplement had an all-trans/9-cis ratio of 19.0, whereas 9-cis betaC was not detected in the low supplement. On d 27, serum and tissues were obtained for HPLC analysis of betaC and its isomers. Analysis of livers showed that all-trans betaC was the primary isomer present, but 9-cis and other isomers were also detected in all groups. The hepatic all-trans/9-cis ratios were 5.9, 4.9, 2.5, 1.4, 52.2 and47.5, respectively, for the groups listed above. Lower amounts of all-trans and 9-cis betaC were found in kidneys compared with the liver, but ratios of all-trans/9-cis were not different among groups. Only trace amounts of 9-cis betaC were found in serum. These results demonstrate that the algae D. bardawil and D. salina provide a bioavailable source of betaC isomers, but, as in humans, absorption of 9-cis betaC is poor and any 9-cis betaC absorbed is apparently cleared by the liver. 相似文献
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The best prototype for designing a new user interface is your old user interface. The second best prototype is a competing product. Your competitors have invested significant resources in designing and implementing what they believe to be good user interfaces. You can glean much of what you need to create a new interface by examining products designed to solve similar problems. As with your own old user interface, you can analyze competing interfaces to see what works and what doesn't. You can also watch how users interact with competing products, and thus learn how they approach tasks. This, in essence, is competitive usability analysis. I recommend performing it very early in the usability engineering life-cycle-after you have visited the customer, gathered requirements, and defined the product vision, but before you design and prototype your new user interface 相似文献