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41.
目的 研究海绵共附生真菌Fusarium equiseti SCSIO 41019的次级代谢产物及抑菌活性。方法 采用中压硅胶柱色谱、中压反相ODS柱色谱及高效液相色谱等方法对发酵产物进行分离和纯化,运用核磁数据及文献对比的方法鉴定化合物结构。采用滤纸片琼脂扩散法、改良肉汤稀释法评价化合物的抑菌活性。结果 从其大米发酵产物中分离并鉴定了8个化合物,分别为equisetin(1)、5'-epiequisetin(2)、lumichrome(3)、N-乙酰基色胺(4)、亚油酸(5)、methyl (4-hydroxyphenyl) acetate(6)、methyl (2-hydroxyphenyl) acetate(7)和graminin B(8)。化合物1、2和5对金黄色葡萄球菌(Staphylococcus aureus)和耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus, MRSA)分别具有不同程度的抑制作用,最小抑菌浓度(minimal inhibitory concentration, MIC)为2.0~125μg/mL,其中化合物1的抑菌活性最强(MIC值分别为2.0和3.9μg/mL)。结论 从菌株Fusarium equiseti SCSIO 41019分离得到两个具良好抑菌活性的化合物(1~2),为将其开发为耐甲氧西林金黄色葡萄球菌的先导化合物提供一定参考。  相似文献   
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Purpose: Parents of children with autism spectrum disorder (ASD) often self-report heightened levels of stress and physical health problems. This paper reviewed studies assessing physiological measures of stress among parents of children with ASD.

Methods: Systematic database searches identified 15 studies meeting inclusion criteria. Studies were reviewed to determine: (a) control group characteristics; (b) caregiver and care recipient characteristics; (c) setting; (d) physiological measures employed; (e) physiological outcomes; and (f) stressor type. A measure of methodological quality was also applied.

Results: Salivary cortisol was the most common physiological measure employed. A pattern of blunted physiological activity emerged within the reviewed studies, though some studies reported normal or even higher physiological activity among this population.

Conclusions: Findings suggested dysfunction of the hypothalamic-pituitary-adrenal-axis and autonomic nervous system for some, but not all, parents of children with ASD. Further research is warranted.  相似文献   

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ABSTRACT

A qualitative grounded theory approach was used to analyze 34 narratives from young men about their experience of retaining, losing, or giving away their virginity, where 7 said they were virgins, 26 said they were non-virgins, and one did not mention his virginity status. We found that virginity is a multidimensional concept, with two distinct dimensions: the experiential and the developmental. The experiential dimension refers to young men's perception and understanding of their virginity in four overlapping areas: physical, spiritual, relational, and emotional. The developmental dimension refers to young men's perception of their underlying sexual identity growth processes and the gendered and sexual double standards that influence this understanding. Clinical implications of this study are useful in education and counseling. They seek to empower young men with information relating to the multidimensional nature of virginity experience, and minimize the negative effects on romantic relationships, sexual adjustment, and self-identity development. The findings are helpful in designing interventions for young men and women who are at high risk for sexually transmitted infections and can help them negotiate mutually safe and pleasurable experiences regarding their virginity.  相似文献   
45.
BackgroundThere is uncertainty about the role of preoperative physical activity (PA) level and its influence on postoperative outcomes, especially for patients undergoing cancer surgery.Aim: To investigate if the level of preoperative PA in patients undergoing cancer surgery is associated with postoperative complication rates, length of hospital stay (LOS) and quality of life (QOL).MethodsAn electronic search was performed from inception to 26th November 2017 in MEDLINE, Embase, AMED and CINAHL. Studies investigating the association between objective or subjective level of PA and postoperative complication rates, LOS and QOL were included. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. When possible, summary odds ratios (OR) and 95% confidence intervals (CI) were calculated using random-effect models.Results13 studies (5523 unique patients) were included. Overall, most studies were rated as having low or moderate risk of bias. Higher preoperative level of PA was not significantly associated with absence of postoperative complications (OR = 2.60; 95%CI = 0.59 to 11.37) but was significantly associated with shorter LOS (OR = 3.66; 95%CI = 1.38 to 9.6) and postoperative QOL (OR = 1.29; 95%CI = 1.11 to 1.49).ConclusionsThe available literature suggests higher levels of preoperative PA in patients undergoing cancer surgery may be associated with better postoperative outcomes, particularly shorter LOS and better QOL. There is a need for high-quality studies investigating the association between preoperative PA and postoperative outcomes.Systematic review registrationPROSPERO 2017 CRD42017082334. Available from:http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42017082334.  相似文献   
46.
《Archives de pédiatrie》2020,27(6):333-337
Background dataLittle is known about daily walking distance levels, which accounts for approximately 80% of overall physical activity per day, in adolescents with idiopathic scoliosis (AIS).ObjectiveThe aim of this study was to assess the level of walking distance in AIS treated by bracing or not, comparing this activity with that of a control group. We used an original method based on smartphone pedometers for studying walking distance in everyday life.MethodsNineteen AIS patients, aged 14.1 (13–17) years, and 25 asymptomatic patients, aged 12.9 (12–14) years were included prospectively. The 19 AIS cases comprised 9 untreated individuals and 10 with ongoing night brace treatment. The mean walking distance per day as estimated by the pedometer application on smartphones for 2 months was assessed. Weekly sports activities (hours per week) were also reported.ResultsDuring the first month, the mean walking distance was 2.58 ± 0.65 km/day for control patients, 2.31 ± 1.38 km/day for untreated AIS, and 3.65 ± 0.72 km/day for AIS patients treated with a night brace. During the second month, the mean walking distance was 2.60 ± 0.73 km/day for control patients, 2.40 ± 1.41 km/day for untreated AIS, and 3.70 ± 0.72 km/day for AIS patients treated with a night brace. Statistical analysis between groups showed a statistically significant difference with a higher level of daily walking distance in adolescents treated with a night brace compared with other groups.ConclusionThe pedometer on smartphones is a cost-effective and friendly tool to assess adolescents’ level of walking distance. Our results indicate no restriction in terms of daily walking distance between adolescents without scoliosis and those with idiopathic scoliosis.Level of evidenceLevel II.  相似文献   
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ABSTRACT

Purpose

The aim of the present study was to assess the association between levels of physical activity (PA) and the presence of cataracts in people aged 15–69 years residing in Spain.  相似文献   
49.
The self is a multifaceted phenomenon that integrates information and experience across multiple time scales. How temporal integration on the psychological level of the self is related to temporal integration on the neuronal level remains unclear. To investigate temporal integration on the psychological level, we modified a well‐established self‐matching paradigm by inserting temporal delays. On the neuronal level, we indexed temporal integration in resting‐state EEG by two related measures of scale‐free dynamics, the power law exponent and autocorrelation window. We hypothesized that the previously established self‐prioritization effect, measured as decreased response times or increased accuracy for self‐related stimuli, would change with the insertion of different temporal delays between the paired stimuli, and that these changes would be related to temporal integration on the neuronal level. We found a significant self‐prioritization effect on accuracy in all conditions with delays, indicating stronger temporal integration of self‐related stimuli. Further, we observed a relationship between temporal integration on psychological and neuronal levels: higher degrees of neuronal integration, that is, higher power‐law exponent and longer autocorrelation window, during resting‐state EEG were related to a stronger increase in the self‐prioritization effect across longer temporal delays. We conclude that temporal integration on the neuronal level serves as a template for temporal integration of the self on the psychological level. Temporal integration can thus be conceived as the “common currency” of neuronal and psychological levels of self.  相似文献   
50.
BackgroundThe effect of tibiofemoral geometry on musculoskeletal function is important to movement biomechanics.Research questionWe hypothesised that tibiofemoral geometry determines tibiofemoral motion and musculoskeletal function. We then aimed at 1) modelling tibiofemoral motion during normal activity as a function of tibiofemoral geometry in healthy adults; and 2) quantifying the effect of tibiofemoral geometry on musculoskeletal function.MethodsWe used motion data for six activity types and CT images of the knee from 12 healthy adults. Geometrical variation of the tibia and femoral articular surfaces were measured in the CT images. The geometry-based tibiofemoral motion was calculated by fitting a parallel mechanism to geometrical variation in the cohort. Matched musculoskeletal models embedding the geometry-based tibiofemoral joint motion and a common generic tibiofemoral motion of reference were generated and used to calculate joint angles, net joint moments, muscle and joint forces for the six activities analysed. The tibiofemoral model was validated against bi-planar fluoroscopy measurements for walking for all the six planes of motion. The effect of tibiofemoral geometry on musculoskeletal function was the difference between the geometry-based model and the model of reference.ResultsThe geometry-based tibiofemoral motion described the pattern and the variation during walking for all six motion components, except the pattern of anterior tibial translation. Tibiofemoral geometry had moderate effect on cohort-averages of musculoskeletal function (R2 = 0.60–1), although its effect was high in specific instances of the model, outputs and activities analysed, reaching 2.94 BW for the ankle reaction force during stair descent. In conclusion, tibiofemoral geometry is a major determinant of tibiofemoral motion during walking.SignificanceGeometrical variations of the tibiofemoral joint are important for studying musculoskeletal function during normal activity in specific individuals but not for studying cohort averages of musculoskeletal function. This finding expands current knowledge of movement biomechanics.  相似文献   
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