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71.
In Argentina, the Pampa ecoregion has been almost completely transformed into agroecosystems. To evaluate the environmental (agricultural area, tree coverage, distance to the nearest water body and urban site) and biological (dove, cowbird, and sparrow abundance) effects on free-ranging bird exposure to St. Louis encephalitis virus (SLEV) and West Nile virus (WNV), we used generalized linear mixed models. For 1,019 birds sampled during 2017–2019, neutralizing antibodies were found against SLEV in samples from 60 (5.8%) birds and against WNV for 21 (2.1%). The best variable for explaining SLEV seroprevalence was agricultural area, which had a positive effect; however, for WNV, no model was conclusive. Our results suggest that agroecosystems in the La Pampa ecoregion increase the exposure of avian hosts to SLEV, thus potentially increasing virus activity.  相似文献   
72.

Objectives

To investigate the prevalence and factors associated with the use of medications of questionable benefit throughout the final year of life of older adults who died with dementia.

Design

Register-based, longitudinal cohort study.

Setting

Entire Sweden.

Participants

All older adults (≥75 years) who died with dementia between 2007 and 2013 (n = 120,067).

Measurements

Exposure to medications of questionable benefit was calculated for each of the last 12 months before death, based on longitudinal data from the Swedish Prescribed Drug Register.

Results

The proportion of older adults with dementia who received at least 1 medication of questionable benefit decreased from 38.6% 12 months before death to 34.7% during the final month before death (P < .001 for trend). Among older adults with dementia who used at least 1 medication of questionable benefit 12 months before death, 74.8% remained exposed until their last month of life. Living in an institution was independently associated with a 15% reduction of the likelihood to receive ≥1 medication of questionable benefit during the last month before death (odds ratio 0.85, 95% confidence interval 0.88–0.83). Antidementia drugs accounted for one-fifth of the total number of medications of questionable benefit. Lipid-lowering agents were used by 8.3% of individuals during their final month of life (10.2% of community-dwellers and 6.6% of institutionalized people, P < .001).

Conclusion

Clinicians caring for older adults with advanced dementia should be provided with reliable tools to help them reduce the burden of medications of questionable benefit near the end of life.  相似文献   
73.
Young adults living with type 1 diabetes often struggle to achieve what clinicians consider to be optimal levels of metabolic control. Despite the impact that this can have on a young person''s future risk of complications, there are relatively few studies reporting new ways of organizing or delivering care to this cohort. In this article, we explore some of the reasons why young adult diabetes care is challenging, and describe approaches to “re‐imagining” how care might be improved. The work is informed by the ‘Making Care Fit’ collaborative and by a program of research, entitled D1 Now, involving co‐design of a complex person‐centered intervention with young adults.  相似文献   
74.
OBJECTIVE: The objectives of our study were to investigate differences in Doppler sonography features between benign and malignant breast lesions and between malignant lesions with different prognostic factors and to propose diagnostic criteria for Doppler sonography of breast lesions. SUBJECTS AND METHODS: We performed power and duplex Doppler sonography examinations in 826 breast lesions scheduled for sonographically guided core needle biopsy. Lesion vascularity, pulsatility index (PI), and resistive index (RI) of the vessels detected were analyzed and correlated with histologic results. RESULTS: Color flow was more frequently seen in malignant (237/348 lesions, 68%) than in benign (171/478, 36%) lesions (p < 0.001). However, sensitivity, specificity, and positive and negative predictive values for this sign were low (68%, 64%, 58%, and 73%, respectively). The RI and PI values were significantly higher (p < 0.001) in cancers. Although an overlap in these values between benign and malignant lesions was observed, all but one nodule with an RI of greater than 0.99 (those with null or inverted diastolic flow) or a PI of greater than 4 were malignant. No significant relationship was found between PI, RI, or flow visualization on power Doppler sonography and tumor grade or lymph node involvement in cancers. CONCLUSION: Flow visualization on power Doppler sonography indicates a higher possibility of malignancy but is not useful as the main sign for malignancy. However, any lesion with a vessel that has an RI value greater than 0.99 or a PI value greater than 4 within it must be considered as probably malignant regardless of any other sonography sign present. Doppler findings are not useful to predict tumor grade or lymph node involvement.  相似文献   
75.
目的观察严重烧伤患者伤后T淋巴细胞亚群、NK细胞活性和sIL2R水平的变化,探讨其免疫功能改变的可能机制。方法测定35例严重烧伤患者伤后T淋巴细胞亚群,NK细胞活性和sIL2R的水平,并与正常对照组进行比较。结果与正常对照组比较,烧伤组:CD3+、CD4+和CD4+/CD8+比值均明显下降(P均<0.01),CD8+明显升高(P<0.05),烧伤组NK细胞活性明显下降(P<0.05),sIL-2R明显升高(P<0.01)。结论严重烧伤患者T淋巴细胞亚群中细胞比例发生了明显改变,NK细胞活性降低sIL-2R水平升高,三者互相影响,共同构成烧伤患者伤后免疫功能紊乱的因素之一。  相似文献   
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Background Behaviours regarding food and activity are learned during childhood and continue throughout life. Children can be very important agents in making decisions concerning their own well‐being and care and their perspective is essential to understanding how they and/or others make choices for them to achieve a healthy lifestyle. However, their perspectives remain under‐researched. This study provides an insight into school children's own perspectives, behaviours and contribution to food and activity choices. Methods The paper reports on the findings from an ethnographic study with 38 Spanish children aged 5–7 years. Information was obtained through participant observations, diaries kept by children and group interviews. Data were analysed using techniques of analytical induction and constant comparison. Results The children who took part in this study described choices about activities with enthusiasm. Children saw activity as a way of learning new things, mastering skills and socializing. They were willing to try and experience new activities and games. However, the activities performed depended on parents' agendas and security issues. In contrast, children reported less interest in and active involvement in food choices. They contributed to family food choices indirectly through the expression of their preferences, not wanting to eat what they disliked or tasting new foods. Conclusion Children had strong preferences and motivations, particularly about activities which could be harnessed in interventions to prevent obesity and promote healthy diet and activity. Parental involvement and commitment is also important both to encourage exercise according to children's interests and active informed food choices, including introduction to unfamiliar foods.  相似文献   
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