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71.
72.
László Prónai Hiroe Nakazawa Kohji Ichimori Yoshinori Saigusa Tomoichi Ohkubo Kazuko Hiramatsu Shigeru Arimori János Fehér 《Inflammation》1992,16(5):437-450
This study was performed to examine the pattern of Superoxide (O
2
–
·) generation from leukocytes using the O
2
–
· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O
2
–
· generation by leukocytes. The time course of O
2
–
· generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O
2
–
· for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O
2
–
· generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O
2
–
· much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O
2
–
· generation by leukocytes. 相似文献
73.
R C de Oliveira A Gon?alves 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(3):233-239
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
74.
75.
M. E. Martín Hortigüela J. M. Ribó Cruz N. Ventura Gómez 《Pediatric surgery international》1992,7(2):146-148
The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed.
Offprint requests to: M. E. Martín Hortigüela 相似文献
76.
P. E. Marchiori M. dos Reis M. E. Quevedo M. Scaff W. Cossermelli J. L. Assis R. M. de Oliveira 《Acta neurologica Scandinavica》1989,80(5):387-389
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
77.
Luciana Butini Oliveira Wagner Marcenes Thiago Machado Ardenghi Aubrey Sheiham Marcelo Bönecker 《Dental traumatology》2007,23(2):76-81
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
78.
79.
The phylogeny of howler monkeys (Alouatta, Platyrrhini): Reconstruction by multicolor cross-species chromosome painting 总被引:2,自引:0,他引:2
Edivaldo H. C. de Oliveira Michaela Neusser Wilsea B. Figueiredo Cleusa Nagamachi Julio Cesar Pieczarka Ives J. Sbalqueiro Johannes Wienberg Stefan Müller 《Chromosome research》2002,10(8):669-683
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca. 相似文献
80.
László Bajnok Bertalan Kozlovszky József Varga Judit Antalffy Sándor Olvasztó Tamás Fülöp Jr. 《European journal of nuclear medicine and molecular imaging》1994,21(12):1326-1332
Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients
with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the
legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over
the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences
between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every
case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures.
The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error
was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied
by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This
phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In
conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral
vascular disease. 相似文献