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991.
Many natural compounds have low water solubility and need to be dissolved in organic solvents, or surfactant agents must be used before addition into experimental systems. Therefore, it is necessary to determine their toxicity. Experiments were performed aiming to select solvents to be used in the bioassays, searching new acaricide agents from plants. Laboratory tests were carried out on larvae and adults of the cattle tick Boophilus microplus to determine the sensibility of B. microplus female and larvae to different solvents (acetone, methanol, ethanol and 1% dimethyl sulfoxide) and surfactant agents (1% Tween 80 and 5% Triton X-100) using the larval immersion test (LIT) and adult immersion test (AIT). In the AIT, the effect of the treatments on engorged females was assessed by measuring egg production and hatching rate. Acetone was toxic to the adults promoting mortality of 100%. Methanol and ethanol caused 45.3 and 14.2% of mortality, respectively. The other tested substances were not toxic to the engorged females of B. microplus. In the LIT, it was observed that the larvae were more resistant; after 48 h, about 100% of the larvae were alive in all the treatments except with acetone that caused a mortality of 10%.  相似文献   
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By application of the real-time PCR we manage to confirm the diagnosis and occurrence of a disease, which is caused by Bordetella pertussis-pertussis. Using this method we have proven the presence of DNA of Bordetella pertussis in the biological materials (nasopharyngeal swabs). The presence of IS481 genome sequence of Bordetella pertussis was confirmed. This method of detection of pathogens seems to be very rapid, simple, and specific. In the case of adequate technical laboratory equipment it may become very suitable and important supporter in explanation and confirmation of the occurrence of bacterial infections.  相似文献   
993.
BackgroundAcute myeloid leukemia (AML) accounts for approximately 20% of pediatric leukemia cases; 30% of these patients experience relapse. The antileukemia properties of natural killer (NK) cells and their safety profile have been reported in AML therapy. We proposed a phase 2, open, prospective, multicenter, nonrandomized clinical trial for the adoptive infusion of haploidentical K562-mb15-41BBL–activated and expanded NK (NKAE) cells as a consolidation strategy for children with favorable and intermediate risk AML in first complete remission after chemotherapy (NCT02763475).Patients and MethodsBefore the NKAE cell infusion, patients underwent a lymphodepleting regimen. After the NKAE cell infusion, patients were administered low doses (1 × 106/IU/m2) of subcutaneous interleukin-2. The primary study endpoint was AML relapse-free survival. We needed to include 35 patients to demonstrate a 50% reduction in relapses.ResultsSeven patients (median age, 7.4 years; range, 0.78-15.98 years) were administered 13 infusions of NKAE cells, with a median of 36.44 × 106 cells/kg (range, 6.92 × 106 to 193.2 × 106 cells/kg). We observed chimerism in 4 patients (median chimerism, 0.065%; range, 0.05-0.27%). After a median follow-up of 33 months, the disease of 6 patients (85.7%) remained in complete remission. The 3-year overall survival was 83.3% (95% confidence interval, 68.1-98.5), and the cumulative 3-year relapse rate was 28.6% (95% confidence interval, 11.5-45.7). The study was terminated early because of low patient recruitment.ConclusionThis study emphasizes the difficulties in recruiting patients for cell therapy trials, though NKAE cell infusion is safe and feasible. However, we cannot draw any conclusions regarding efficacy because of the small number of included patients and insufficient biological markers.  相似文献   
994.
ObjectiveThe aim of this study is to analyze the prognostic role of lymph-vascular space invasion (LVSI), evaluated in a semi-quantitative fashion on prognosis of early stage, low risk endometrial cancer (EC).MethodsWe enrolled patients who underwent surgery for endometrial cancer between 2003 and 2018 in two referral cancer center. All patients had endometrioid EC, G1–G2, with myometrial invasion <50%, and no lymph-node involvement. LVSI was analyzed in a semi-quantitative way, according to a 3-tiered scoring system in absent, focal and substantial.ResultsAmong 524 patients, any positive LVSI was found in 57 patients (10.9%) with focal LVSI (n=35, 6.7%) and substantial LVSI (n=22, 4.2%). Substantial LVSI was associated to higher rate of G2 (p<0.001), myometrial infiltration (p=0.002) and greater tumor dimensions (p=0.014). Patients with substantial LVSI were more likely to receive adjuvant treatment (6.6% vs. 52.6%, p<0.001). The 5-year OS was 99.5% in patients with absent LVSI and 70.6% in those with substantial LVSI (p<0.001). The 5-year disease free survival (DFS) was 93.6% in patients with absent LVSI and 56.5% in those with substantial LVSI (p<0.001). The rate of distant failures increased from 1.8% for absent LVSI to 22.7% for substantial LVSI (p=0.002). In univariate analysis substantial LVSI was the strongest predictor of poor overall survival (hazard ratio [HR]=11.9, p=0.001). Multivariate analysis showed that substantial LVSI was an independent predictive factor of both recurrence (HR=5.88, p=0.001) and distant failure (HR=10.6, p=0.006).ConclusionsSubstantial LVSI represents the strongest independent risk factor for decreased survival and distant relapse, indicating a role for potential hematogenous dissemination.  相似文献   
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OBJECTIVE: To translate the Family Environment Scale into Portuguese and apply the instrument to validate it. METHODS: The translation was applied to members of Brazilian families with the aim of evaluating its internal consistency and the concordance between members of the same family. One hundred and fifty-four volunteers living in the city of S?o Paulo in 2003 who were not receiving any kind of intervention for dealing with family problems were selected. The mean scores in the ten subscales of the instrument were compared between men and women, and between members of the same family. The internal consistency was evaluated by means of Cronbach's alpha. RESULTS: The maximum possible score in each subscale was nine (good family functioning), except in relation to conflict and control. In most of the subscales, the mean score of the sample studied ranged from 5.1 to 7.6 (men) and 5.4 to 7.7 (women). In the conflict and control subscales, the means ranged from 1.8 to 4.6 (men) and 1.6 to 4.6 (women). These were similar to scores reported in international studies, except for higher scores in the cohesion and organization subscales, and lower score in the conflict subscale. There were no statistically significant differences between the scores attained by men and women. The reliability of the scale, evaluated according to Cronbach's alpha, ranged from 0.61 to 0.78 for the ten subscales. CONCLUSIONS: Cultural factors may have influenced the results obtained in some of the subscales. The Portuguese version of the Family Environment Scale presented reasonable internal consistency that enables its use for evaluating changes in the family's environment and its functioning and after therapeutic interventions.  相似文献   
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