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31.
Fluorescence in situ hybridization (FISH) with α-satellite DNA probes was used to study whole-arm chromosome translocation products in a family in which the propositus was shown to have a monosomy 18p/trisomy 20p imbalance. By this approach, we show that the chromosome 18 α-satellite DNA block is split into 2 smaller units, whereas the chromosome 20 breakpoint is not included within the α-satellite DNA region. We found no evidence to suggest that this split α-satellite DNA region has reduced or impaired the function of the centromere or that it contributed to the phenotype of the propositus. The FISH technique critically demonstrated the involvement of a whole-arm translocation in this case and provided accurate identification of breakpoints, which was not possible with standard banding techniques. © Wiley-Liss, Inc.  相似文献   
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In Brazil, Public Health specialization courses with the characteristics presently adopted by the National School of Public Health, i.e., short duration and great amplitude, are relatively recent, having started approximately fifteen years ago. In Brasília, nine such courses have been already completed, having, six of them, directive and/or teaching involvement by the authors. Results on a final assessment of one the courses are herewith presented in order to introduce our experience as a contribution to future analogous initiatives. The assessment was applied to a random sample of students, teachers and coordinators, with the objective of identifying positive and negative appreciations about methodological, operational, administrative and institutional aspects. Answers were quite variable, with the highest frequencies scored to field work and to the apprehension on admitting graduates to the Health System. Such aspects deserve final differentiated discussion.  相似文献   
34.
Radioimmunoassay techniques were used to detect antibodies to the acetylcholine receptor (AAChR) in 164 patients with adult-onset myasthenia gravis. AAChR levels above 0.6 nM/l were considered pathological and were found in 67% of the patients with an average value of 58.99 +/- 125.02 nM/l (0.6-900.0). Correlation, with clinical functional status, the histopathological thymus alterations and the different therapeutics used did not disclose any statistically significant differences.  相似文献   
35.
Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P  = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI.  相似文献   
36.
OBJECTIVE: Clinical, radiographic, and microbiologic changes in deep caries lesions were assessed after incomplete carious dentin removal and tooth sealing. METHOD AND MATERIALS: Thirty-two teeth with deep caries lesions were studied. Treatment consisted of incomplete excavation of the demineralized dentin, application of calcium hydroxide, and sealing for a 6- to 7-month period. The color and consistency of the dentin were clinically assessed. Differences in radiographic density were assessed by digital image subtraction. Microbiologic samples were obtained from the demineralized dentin before the temporary sealing and after the experimental period. The samples were cultivated on blood agar under aerobic and anaerobic conditions, in Mitis Salivarius agar, and Rogosa selective Lactobacillus agar. RESULTS: Two cases were lost during the study; one presented pulpal necrosis. In the other case, there was pulpal exposure during removal of provisional sealing. In all teeth, the initial demineralized dentin was soft and wet; one lesion was yellow, 21 were light brown, and eight were dark brown. After treatment, the dentin was dry, and 80.00% of specimens were hard, 16.67% were leathery, and 3.33% remained soft. The dentin was light brown in five teeth and dark brown in 25. There was a statistically significant mean difference in radiographic density (pixel intensity), 88.77 +/- 7.02 in the control areas and 94.66 +/- 6.75 in the test areas. The counts of anaerobic and aerobic bacteria, lactobacilli, and Streptococci mutans had decreased significantly by the end of treatment. CONCLUSION: Incomplete removal of carious dentin and subsequent tooth sealing resulted in the arrest of the lesions, suggesting that complete dentinal caries lesion removal is not essential to the control of caries lesions.  相似文献   
37.
Grip strength is one of the traditional outcome measures commonly used in rheumatoid arthritis trials. This study evaluated the degree of morning variation and the effect of elbow flexion in the assessment of grip strength in patients with rheumatoid arthritis. Grip strength was measured in 37 patients (1987 American Rheumatism Association criteria) at 8, 10, and 12 AM with a sphygmomanometer cuff folded on itself, taped permanently, and inflated to 20 mm Hg, with the elbow flexed at 90 degrees. At 10 AM grip strength was also measured with the elbow flexed at 30 and 130 degrees. Mean values for grip strength at 8, 10, and 12 AM were, respectively, 69, 79, and 83 mm Hg. Mean grip strength values with the elbow flexed at 30, 90, and 130 degrees were, respectively, 78, 79, and 75 mm Hg. There was a statistically significant correlation between grip strength and morning stiffness, grip strength and hand function, and grip strength and number of active joints. In rheumatoid arthritis trials, grip strength should be assessed at the same time of the day. Elbow flexion does not play a role in grip strength measurement.  相似文献   
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39.
Medullary sponge kidney and congenital hemi-hypertrophy   总被引:2,自引:0,他引:2  
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40.
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore.  相似文献   
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