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61.
Fernández Rodríguez R Porto Golpe I Lema Mougán R Lechuga García R Labella Caballero T 《Acta otorrinolaringologica espanola》1999,50(7):539-542
Involvement of the cervical lymph nodes is one of the commonest forms of extrapulmonary tuberculosis. Given this, we carried out a retrospective study of those cases diagnosed in our health region from 1995-1997, looking at the diagnostic criteria and treatment regimes and comparing our findings with those of other authors. 相似文献
62.
The essential oils from aerial parts of young (sample A) and mature leaves (sample B), fruit (sample C), and flowers (sample D) of Zanthoxylum hyemale were obtained by hydrodistillation and analyzed by GC, GC/MS, and chiral phase gas chromatography (CPGC). Thirty-four compounds were identified from the essential oils, representing approximately 90.71, 91.19, 87.33, and 89.08 % of the oils, respectively. The major constituent of the young leaf essential oil was the sesquiterpene trans-nerolidol (51 %), while the main constituent of mature leaf (31 %) and flower oils (22 %) was an as yet unknown humulane-type sesquiterpenoid, which was characterized by spectral techniques (EI-MS and 1D-, 2D-NMR) as 3,7,10,10-tetramethylcycloundeca-3,7-dien-1-ol ( 1) and given the trivial name "hyemalol". In the fruit essential oil, the most abundant components were the monoterpenes beta-pinene (25 %) and alpha-pinene (10 %). The antimicrobial activity of the essential oils and some isolated compounds is also reported. 相似文献
63.
Fujiki EN Kuwajima SS Honda EK Milani C Porto LC Chikude T Fukushima WY Ono NK 《Journal of pediatric orthopedics》2005,25(4):450-455
From May 1990 to November 1997, 24 cases of severe slipped capital femoral epiphysis were treated by an osteotomy that is a modification of the Hungria-Kramer intertrochanteric osteotomy proposed by Sugioka (Hungria-Kramer-Sugioka osteotomy or HKS osteotomy). The degree of displacement as seen on the frog-leg lateral radiograph of the proximal femur was measured according to the deviation of the longitudinal axis of the epiphysis from the center line of the neck (Fish classification). All hips were considered as grade III and underwent HKS osteotomy. Sugioka's radiographic study (true AP view with the limb internally rotated until the patella is perpendicular to the x-ray beam, and lateral view with the hip in 90 degrees flexion and 45 degrees abduction) was performed before surgery to show that the real direction of the slip was posterior in relation to the neck. Clinical results were assessed according to Merle-D'Aubigné and Postel system modified by Charnley (hip score system that takes into consideration pain, gait, and joint motion). Roentgenographic results were considered good if none of the following was present: joint space decreased by more than 2 mm (chondrolysis), avascular necrosis of the femoral head, neck-shaft angle of less than 120 degrees, nonunion at the osteotomy site, and a epiphyseal plate still open. Follow-up varied from 31 to 120 months (average 65.1 months). 相似文献
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Porto MF Juncá DC Gonçalves Rde S Filhote MI 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2004,20(6):1503-1514
This article presents the results of a study on the lives, work, and health conditions of garbage pickers in the largest metropolitan landfill in Rio de Janeiro, Brazil. Using a semi-structured questionnaire with open-ended and closed questions, the study interviewed these individuals and developed a discussion of their daily lives, work, and health conditions. According to a quantitative-qualitative analysis, the garbage pickers identified garbage as a source of survival and defined health simply as the ability to work. They thus tended to neglect the relationship between work and health. However, the risks and reported morbidity highlighted the hazardous nature of this activity, aggravated by their living and housing conditions. Finally, the article emphasizes the importance of establishing public policies that integrate different dimensions of the problem, such as social inclusion, environmental preservation, public health, and the dignity of these workers. 相似文献
67.
Delcor NS Araújo TM Reis EJ Porto LA Carvalho FM Oliveira e Silva M Barbalho L de Andrade JM 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2004,20(1):187-196
The scientific literature on teachers' health is scarce, recent, and focuses predominantly on stress and burnout. This study describes the labor conditions of private school teachers in Vitória da Conquista, Bahia State, Brazil. Information on 250 teachers from the ten largest schools in the municipality was collected through a self-applied questionnaire. The most relevant characteristics of teachers' work, evaluated by the Job Content Questionnaire were: speed of work, creativity at work, and relations with colleagues. The most frequent complaints related to posture, mental strain, and voice problems. Prevalence of minor psychological disorders according to the Self Reporting Questionnaire-20 was 41.5%, strongly associated with long periods of intense concentration on the same job and excessive work. Results suggest an association between the prevalence of minor psychological disorders and certain characteristics of teaching work, emphasizing teachers' exposure to stress. 相似文献
68.
The induction threshold, and the magnitude and direction of changes in synaptic plasticity may depend on the previous history of neuronal activity. This phenomenon, termed "metaplasticity," could play an important role in integration processes by coordinating the modulation of synapses. Although metaplasticity has been analyzed extensively, its underlying cellular mechanisms remain largely unknown. Using in vitro electrophysiological and computer simulation approaches, we investigated the contribution of the slow Ca2+-dependent afterhyperpolarization (sAHP) in the metaplastic control of the induction of long-term potentiation (LTP) at convergent CA3-CA1 pyramidal neuron synapses. We report that classical conditioning protocols may lead to the simultaneous induction of a sustained homosynaptic LTP and a potentiation of the sAHP that endured approximately 1 h. The sAHP potentiation dramatically altered the spike responses of the CA1 pyramidal neuron. Of particular interest was the reduction of the CA1 neuron excitability and, consequently, of the capacity of a nonpotentiated synaptic input to elicit spikes while the sAHP was potentiated. This reduction in excitability temporarily prevented nonpotentiated synaptic inputs to exhibit an LTP induced by presynaptic tetanization. This metaplasticity was strongly resistant to increases in the magnitude of synaptic tetanization protocols. We propose that this heterosynaptic metaplasticity, mediated by intrinsic cellular mechanisms, triggered by brief periods of activity, and relying on changes of a slow Ca2+-activated K+ current, may contribute to adjusting the efficacy of synaptic connections and shaping network behavior to regulate integration processes. 相似文献
69.
de Freitas V da Silva Porto P Assunção M Cadete-Leite A Andrade JP Paula-Barbosa MM 《Alcohol and alcoholism (Oxford, Oxfordshire)》2004,39(4):303-311
Aims: In a previous study, we found that prolonged oxidativestress produced by chronic ethanol consumption leads to an increasedformation of lipofuscin in hippocampal and cerebellar neurons.This pigment is an end-result of lipid peroxidation. Flavanols,which abound in the human diet, are known to exert a powerfulin-vitro antioxidant action. Therefore, to evaluate whetherthese compounds might display beneficial effects in the ratbrain, we examined whether or not these natural antioxidantswould impede neuronal ethanol-induced lipofuscin accumulation.Methods: Adult rats were fed for 6 months either with 20% ethanolsolution or with the same solution to which a mixture of grapeseed catechins and oligomeric procyanidins (200 mg/l) was added.Controls ingested either tap water or water supplemented withthe antioxidant compound. The total amount of lipofuscin inthe hippocampal CA1 and CA3 pyramids and in the cerebellar Purkinjecells was estimated by applying unbiased stereological methods.The mean volume of the neurons was estimated using the nucleatorand the volumetric density of lipofuscin was calculated by pointcounting. Results: Flavanols prevented the accumulation of neuronallipofuscin in the animals submitted to ethanol feeding (i.e.under conditions of increased oxidative stress) but not in thewater-drinking controls. The neuronal volume did not alter amongthe groups studied. Conclusions: Data obtained show that consumptionof flavanols can reduce the effects of oxidative activity broughtabout by alcohol consumption, indicating that these compoundsmight display neuronal beneficial effects under oxidative stress. 相似文献
70.