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101.
The COVID-19 pandemic has resulted in an unprecedented global demand for in vitro diagnostic reagents. Supply shortages and hoarding have impacted testing capacity which has led to inefficient COVID-19 case identification and transmission control, predominantly in developing countries. Traditionally, RNA extraction is a prerequisite for conducting SARS-CoV-2 nucleic acid amplification tests (NAAT); however, simplified methods of sample processing have been successful at bypassing typical nucleic acid extraction steps, enabling extraction-free SARS-CoV-2 NAAT workflows. These methods involve chemical and physical approaches that are inexpensive and easily accessible alternatives to overcome extraction kit supply shortages, while offering acceptable test performance. Here we provide an overview of three main sample preparation strategies that have been shown to facilitate extraction-free SARS-CoV-2 NAATs.  相似文献   
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The emergence of SARS-CoV-2 triggering the COVID-19 pandemic ranks as arguably the greatest medical emergency of the last century. COVID-19 has highlighted health disparities both within and between countries and will leave a lasting impact on global society. Nonetheless, substantial investment in life sciences over recent decades has facilitated a rapid scientific response with innovations in viral characterization, testing, and sequencing. Perhaps most remarkably, this permitted the development of highly effective vaccines, which are being distributed globally at unprecedented speed. In contrast, drug treatments for the established disease have delivered limited benefits so far. Innovative and rapid approaches in the design and execution of large-scale clinical trials and repurposing of existing drugs have saved many lives; however, many more remain at risk. In this review we describe challenges and unmet needs, discuss existing therapeutics, and address future opportunities. Consideration is given to factors that have hindered drug development in order to support planning for the next pandemic challenge and to allow rapid and cost-effective development of new therapeutics with equitable delivery.  相似文献   
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Caecal diverticulitis is an uncommon phenomenon in western countries. The clinical diagnosis is often difficult as it mimics other acute abdominal conditions like appendicitis, colitis or neoplasia. Diagnosis is often made at operation. Operative strategy has been controversial and there is no broad consensus emerging. We report the case of a 71-year-old woman, known to have chronic obstructive pulmonary disease, who presented acutely with right iliac fossa pain. A clinical diagnosis of appendicitis was made. At laparoscopy, a solitary, inflamed, gangrenous caecal diverticulum was found. A laparoscopic stapled diverticulectomy was performed. The patient made a steady post-operative recovery. Histology confirmed diverticulitis. We conclude that stapled diverticulectomy for solitary caecal diverticulitis is a safe and effective surgical strategy when confronted with this scenario.  相似文献   
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Team Reach Out Biloxi is a nursing student-initiated service-learning project with the goal of providing ongoing assistance to the victims of Hurricane Katrina. On 6 different occasions from 2005 to 2008, Purdue nursing students integrated their leadership skills with application of public health knowledge, compassion, and concern as they worked in partnership with the Gulfport region Coastal Family Health Clinics (CFHC). This article reviews the service-learning framework, course planning, and implementation of a 3-year posthurricane disaster project.  相似文献   
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Team Reach Out started as a student-initiated service-learning project with the goal of providing on-going assistance to the victims of Hurricane Katrina. Four years after Hurricane Katrina, Team Reach Out refocused efforts to Cape Town, South Africa, where 4 senior nursing students and 1 science student integrated their leadership skills with the application of public health knowledge, compassion, and concern to work in partnership with several international health agencies. This article reviews the service-learning framework, course planning, and implementation of a recent service-learning project.  相似文献   
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Summary Telomere length decreases with age and is associated with osteoblast senescence. In 2,150 unselected women, leukocyte telomere length was significantly correlated with bone mineral density. Clinical osteoporosis was associated with shorter telomeres, suggesting that telomere length can be used as a marker of bone aging. Introduction The length of telomeres in proliferative cells diminishes with age. Telomere shortening and telomerase activity have been linked to in vitro osteoblast senescence and to increased secretion of pro-inflammatory cytokines. We explored whether bone mineral density correlates with telomere length in leukocytes. Materials and methods The relationship between leukocyte telomere length, bone mineral density (BMD) and osteoporosis (as defined by the World Health Organization) was examined in a cohort of 2,150 women from a population-based twin cohort aged 18–79. Results After adjusting for age, body mass index, menopausal status, smoking, hormone replacement therapy status, telomere length was positively correlated with BMD of the spine (p < 0.005), forearm (p < 0.013), but not the femoral neck (p < 0.06). Longer telomeres were associated with reduced the risk of clinical OP at two or more sites (odds ratio = 0.594 95% CI 0.42–0.84 p < 0.003) and in women over the age of 50, clinical osteoporosis was associated with 117 bp shorter telomere length (p < 0.02) equivalent to 5.2 years of telomeric aging. Conclusions Shortened leukocyte telomere length is independently associated with a decrease in BMD and the presence of osteoporosis in women. Our data provide evidence that leukocyte telomere length could be a marker of biological aging of bone.  相似文献   
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