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991.
Plant Ecology - Key functions of fine roots are often related to their morphological traits, yet little is known about the patterns and controls on fine-root morphological traits in the tropical...  相似文献   
992.
Anthropogenic disturbance has generated a significant loss of biodiversity worldwide and grazing by domestic herbivores is a contributing disturbance. Although the effects of grazing on plants are commonly explored, here we address the potential multi‐trophic effects on animal biodiversity (e.g. herbivores, pollinators and predators). We conducted a meta‐analysis on 109 independent studies that tested the response of animals or plants to livestock grazing relative to livestock excluded. Across all animals, livestock exclusion increased abundance and diversity, but these effects were greatest for trophic levels directly dependent on plants, such as herbivores and pollinators. Detritivores were the only trophic level whose abundance decreased with livestock exclusion. We also found that the number of years since livestock was excluded influenced the community and that the effects of grazer exclusion on animal diversity were strongest in temperate climates. These findings synthesise the effects of livestock grazing beyond plants and demonstrate the indirect impacts of livestock grazing on multiple trophic levels in the animal community. We identified the potentially long‐term impacts that livestock grazing can have on lower trophic levels and consequences for biological conservation. We also highlight the potentially inevitable cost to global biodiversity from livestock grazing that must be balanced against socio‐economic benefits.  相似文献   
993.
We have investigated the effect of deuteration of non‐exchangeable protons on protein global thermal stability, hydrophobicity, and local flexibility using well‐known thermostable model systems such as the villin headpiece subdomain (HP36) and the third immunoglobulin G‐binding domain of protein G (GB3). Reversed‐phase high‐performance liquid chromatography (RP‐HPLC) measurements as a function of temperature probe global thermal stability in the presence of acetonitrile, while differential scanning calorimetry determines thermal stability in solution. Both indicate small but measurable changes in the order of several degrees. RP‐HPLC also permitted quantification of the effect of deuteration of just three core phenylalanine side chains of HP36. NMR dynamics investigation has focused on methyl axes motions using cross‐correlated relaxation measurements. The analysis of order parameters provided a complex picture indicating that deuteration generally increases motional amplitudes of sub‐nanosecond motion in GB3 but decreases those in HP36. Combined with earlier dynamics measurements at Cα–Cβ sites and backbone sites of GB3, which probed slower time scales, the results point to the need to probe multiple atoms in the protein and variety of time scales to the discern the full complexity of the effects of deuteration on dynamics.  相似文献   
994.
995.
Firearm injury in children and adolescents and the morbidity associated with it is an appreciable burden in resource-limited settings, though it is under-reported. This study aimed to determine its prevalence and pattern in Nigerian civilian trauma setting. We undertook a retrospective study of all the patients with firearm injury aged 19 years or under who visited the Emergency Department (ED) of two tertiary hospitals in Nigeria over a period of 15 years. Of the 46,734 children and adolescents seen in the ED, firearm injury was the reason for the visit in 56 of them, giving a prevalence of 1.2 per 1000 ED attendance (95% CI: 0.9-1.6). The male-to-female ratio was 1.8:1, and the mean age was 13.98 ± 5.6 years. The preponderance of firearm injury was in the rural areas, during the dry season, at home, and in the daytime. Armed robbery (20, 35.7%) and communal clash (7, 12.5%) were the two topmost incidents leading to gunshot wounds. Armed robbery-related gunshot occurred mostly on the roads and at nighttime and involved predominantly 15-19-year-olds. Lower extremity was the topmost anatomical region involved. The majority (67%) had no pre-hospital care; the mean and median injury-hospital arrival interval respectively was 352 hrs and 4.2 hrs. Wound infection was the topmost complication. The mean hospital length of stay was 22.6 days. One (1.8%) of the patients died on the third day of hospital admission. Educational campaigns for prevention intensified during the dry season should highlight the risk of firearm injury to this age group and emphasize the importance of proper supervision and guidance of vulnerable children and adolescents. Improving the rates of pre-hospital care and early presentation of victims to the hospital should be considered in tertiary injury prevention strategies.  相似文献   
996.
Neurochemical Research - Epilepsy affects 50 million people around the world, and the patients experience cognitive, psychological and social consequences. Despite the considerable quantity of...  相似文献   
997.
Environmental Biology of Fishes - The Potamotrygon from the Potamotrygonidae family is a freshwater stingray that is native to and distributed throughout South American watersheds. The degradation...  相似文献   
998.

Background

Tetralogy of Fallot is a congenital heart disease that requires surgical repair without which survival through childhood is extremely rare. The aim of this paper is to use data from the mandatory follow-up of patients with Tetralogy of Fallot to model the health-related costs and outcomes over the first 55-years of life.

Method

A decision analytical model was developed to establish costs and outcomes for patients up to 55 years after diagnosis and first repair of Tetralogy of Fallot compared to natural progression. Data from Adult Congenital Heart Disease (ACHD) centres that follow up Tetralogy of Fallot patients and Great Ormond Street Hospital (GOSH), London, United Kingdom (UK) medical records was used to establish the cost and effectiveness of current interventions. Data from a Czech cohort was used for the natural, no intervention condition.

Results

The average cost per patient of a repair for Tetralogy of Fallot was £26,938 (SE = £4,140). The full life time cost per patient, with no discount rate, was £65,310 (95% CI £64,981–£65,729); £56,559 discounted (95% CI £56,159–£56,960). Patients with a repair had an average of 35 Quality Adjusted Life Years (QALYs) per patient over 55 years undiscounted and 20.16 QALYs discounted. If the disorder was left to take its natural course, patients on average had a total of 3 QALYs per patient with no discount rate and 2.30 QALYs discounted.

Conclusion

A model has been developed that provides an estimate of the value for money of an expensive repair of a congenital heart disease. The model could be used to test the cost-effectiveness of making amendments to the care pathway.  相似文献   
999.

Background

Although cervical cancer is ​​the second most common tumor among Brazilian women, studies that evaluate the quality of life of these women are still scarce. This situation is explained by the lack of specific and validated tools for this purpose in Portuguese (Brazil). The aim of this study was to evaluate the psychometric properties of the Portuguese version of the FACT-CX (Functional Assessment of Cancer Therapy-Cervix) questionnaire in a population of Brazilian women with cervical cancer.

Methods

The psychometric properties of the FACT-CX questionnaire were tested in a sample of 100 women diagnosed with cervical cancer who were previously treated in the Barretos Cancer Hospital. We analyzed the internal consistency (Cronbach''s alpha), reproducibility (intraclass correlation coefficient - ICC), confirmatory factor analysis, convergent validity (correlation with the SF-36 questionnaire), and discriminant validity by disease stage and two questions related to self-perception of health was also performed.

Results

The scales had Cronbach´s alpha coefficients ranging from 0.61 to 0.80. However, three scales did not have a statistically significant coefficient greater than 0.70. The ICC ranged from 0.68 to 0.82 and all considered satisfactory. Factor analysis did not generate consistent components. The FACT-G and FACT-CX total scores had good internal consistency and reproducibility, and also correlated well with the General Health and Vitality scales of the SF-36. However, only two FACT-CX scales had a significant correlation with SF-36. Discriminant analysis showed that FACT-CX failed to discriminate groups according to clinical stage but was able to divide the women according to the self-perception of health.

Conclusion

FATC-CX total score had good internal consistency, reproducibility and discriminant validity. In addition, it correlated well with General Health and Vitality scales of SF-36. However, three scales had questionable internal consistency and only two had significant correlation with SF-36.  相似文献   
1000.

Background

Population studies on trends of varicella and herpes zoster (HZ) associated with varicella zoster vaccination and climate is limited.

Methods

This study used insurance claims data to investigate the chronological changes in incident varicella and HZ associated with varicella zoster vaccination. Poisson regression was used to estimate the occurrence of varicella associated with the occurrence of HZ and vice versa by year, season, sex, temperature, and sunny hours.

Results

The varicella incidence declined from 7.14 to 0.76 per 1,000 person-years in 2000–2009, whereas the HZ incidence increased from 4.04 to 6.24 per 1,000 person-years. Females tended to have a higher risk than men for HZ (p<0.0001) but not varicella. The monthly mean varicella incidence was the lowest in September (160 cases) and the highest in January (425 cases), while the mean HZ incidence was lower in February (370 cases) and higher in August (470 cases). HZ was negatively associated with the incidence of varicella before and after the varicella zoster vaccination (p<0.001), increased 1.6% within one week post-vaccination. The effect of temperature on HZ was attenuated by 18.5% (p<0.0001) in association with vaccination. The varicella risk was positively associated with sun exposure hours, but negatively associated with temperature only before vaccination.

Conclusions

The varicella vaccination is effective in varicella prevention, but the incidence of HZ increases after vaccination. HZ has a stronger association with temperature and UV than with seasonality while varicella risk associated with temperature and UV is diminished.  相似文献   
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