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91.
In this study, we verified the possible role of cyclophosphamide (CY) in protecting or not against neuronal losses in young and aged male Calomys callosus chronically infected with the MORC-1 strain of Trypanosoma cruzi through numerical quantification of neurons from the myenteric plexus of the colon and quantification of nitric-oxide concentration (NO) during the acute and chronic phase of infection. For this purpose, groups of young C. callosus were infected with the MORC-1 strain of T. cruzi. A group of infected animals received i.p. 0.2 mg/ml genuxal dissolved in distilled water treatment with CY. NO concentration in aged animals displayed reduced levels when compared to those found in young animals. No significant alterations in the number of neurons were observed in young animals, but for aged ones, a protective role of CY in reducing neuron loss was noted, in addition to enhancing the neuronal volume, area, and perimeter. These results suggest that CY administration, depending on the dose and time span, can act as a protective agent against neuronal losses.  相似文献   
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This study compared the course of Ancylostoma ceylanicum infection in hamsters infected with different inocula and the consequences for the host and helminth populations. The average of adult worms recovered, according to the number of third stage larva used, were 28.0, 24.8, 24.6, and 24.8 % to inocula size of 25 L3, 75 L3, 125 L3, and 250 L3, respectively. The size of the inoculum did not affect the establishment, survival, or fecundity of adult helminths. Reductions in the red blood cell and hemoglobin levels in the infected group were inversely proportional to the number of white blood cells. Moreover, differential cell counting revealed a positive correlation between the worm load and leucocyte numbers. The humoral response against excretion-secretion antigens was more robust and sensitive compared with the response against crude extract, with no direct linear correlation with the number of worms. The effect of the population density was more evident in females.  相似文献   
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The objective was to determine the effects of carbohydrate (CHO) supplementation on exercise-induced hormone responses and post-training intramyocellular lipid stores (IMCL). Twenty-four elite male athletes (28.0 ± 1.2 years) were randomized to receive CHO (maltodextrin solution) or zero energy placebo solution (control group). The high-intensity running protocol consisted of 10 × 800 m at 100% of the best 3000-m speed (Vm3 km) and 2 × 1000 m maximal bouts in the morning and a submaximal 10-km continuous easy running in the afternoon of day 9. IMCL concentrations were assessed by 1H-MRS before (?day 9) and after training (day 9) in soleus (SO) and tibialis anterior (TA) muscles. Blood hormones were also measured before, during, and post-exercise. The percent change (Δ%) in TA-IMCL was higher in the CHO group (47.9 ± 24.5 IMCL/Cr) than in the control group (?1.7 ± 13.1, respectively) (P = .04). Insulin concentrations were higher in the CHO group post-intermittent running compared to control (P = .02). Circulating levels of free fatty acids and GH were lower in the CHO group (P > .01). The decline in performance in the 2nd 1000-m bout was also attenuated in this group compared to control (P < .001 and P = .0035, respectively). The hormonal milieu (higher insulin and lower GH levels) in the CHO group, together with unchanged free fatty acid levels, probably contributed to the increased IMCL stores. This greater energy storage capacity may have improved post-exercise recovery and thus prevented performance deterioration.  相似文献   
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The present study had three objectives: (a) to characterize the functional capacity of patients with PD, (b) to assess the relationship between the physical fitness components of functional capacity with clinical characteristics and disease severity, and (c) to compare the physical fitness components of functional capacity with clinical characteristics according to disease severity. The study included 54 patients with idiopathic PD who were distributed into two groups according to PD severity: unilateral group (n=35); and bilateral group (n=19). All patients underwent psychiatric assessment by means of the Hoehn and Yahr (HY) staging of PD, the Unified Parkinson's Disease Rating Scale (UPDRS), the Hospital Anxiety and Depression Scale (HADS-A and HADS-D, respectively), and The Mini-Mental State Examination (MMSE). The physical fitness components of functional capacity were evaluated over a 2-day period, using recommendations by the American Alliance for Health, Physical Education, Recreation and Dance, and the Berg Balance Scale (BBS). Pearson correlation coefficients and multiple regressions were calculated to test the correlation between functional capacity and clinical characteristics, and to predict clinical scores from physical performance, respectively. Clinical variables and physical component data were compared between groups using analysis of variance to determine the effects of disease severity. Patients with advanced disease showed low levels of functional capacity. Interestingly, patients with good functional capacity in one of the physical fitness components also showed good capacities in the other components. Disease severity is a major factor affecting functional capacity and clinical characteristics. Medical providers should take disease severity into consideration when prescribing physical activity for PD patients, since the relationship between functional capacity and clinical characteristics is dependent on disease severity.  相似文献   
99.
International Journal of Paediatric Dentistry 2012; 22: 286–291 Background. In dentistry, clinical practice is directed towards attitudes that promote oral health and the paediatricians occupy a privileged position in this process. Aim. To assess the knowledge and attitudes of paediatricians in relation to the oral health of their patients. Design. A cross‐sectional study was carried out at the Institute of Integrative Medicine Professor Fernando Figueira, Recife, Brazil. A total of 182 paediatricians participated by filling out a questionnaire. Results. A total of 63.9% believed the first visit to the dentist should occur before the child completes 1 year of life. Moreover, 67.8% considered their knowledge on oral health to be insufficient. Approximately 78% of the paediatricians diagnosed caries through an analysis of cavities. Only 29.9% always recommended fluoride dentifrice. The term ‘fluorosis’ was unknown by 48.3% of the respondents. Concerning pacifiers, 32.6% did not allow it and 66.9% did not either recommend it or restrict it. A total of 83.4% classified the oral health content in their medical education as either nonexistent or deficient; this figure remained high (72.4%) in relation to residency. Conclusions. It is important to develop oral health information programmes to paediatricians. Information on oral health should be included in medical curricula and residency.  相似文献   
100.
PurposeThe aim of the present study was to evaluate commercially pure titanium (CP Ti) casting quality when a specific to titanium and a conventional phosphate bonded investments were used under different mold temperatures. For this, the evaluated parameters were surface roughness, bending strength, Vickers microhardness, casting quality by radiographies and microstructure of CP Ti.MethodsWax patterns (28 mm × 3 mm × 1 mm) were invested using two phosphate bonded investments: Rematitan Plus (REM), specific to titanium, and Castorit Super C (CAS), a conventional investment, fired and cooled until reaching two mold temperatures: 430 °C (430) and room temperature (RT). Specimens were cast from CP Ti by plasma. After casting, specimens were radiographically examined and submitted to Vickers microhardness, roughness and bending strength evaluation. Microstructure was analyzed in the center and at the surface of specimen.ResultsQualitative analysis of radiographs showed that specimens which were cast using CAS-RT presented more casting porosities while the specimens which were cast with REM-430 did not present any casting porosity. No significant difference was noted among the groups in the surface roughness and Vickers microhardness data, but the bending strength of the specimens cast using CAS was greater than REM groups. The microstructure of the specimens of the different groups was similar, presenting a feather-like aspect.ConclusionCasting porosities found in the specimens cast using conventional investments (CAS) and lower mold temperatures would limit their use, even mechanical properties were similar than in specimens cast using specific to titanium investment (REM) at temperatures recommended by the manufacturer.  相似文献   
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