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1.
Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV1 < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture.  相似文献   
2.
The impact of proximity to a beef cattle feedlot on Escherichia coli O157:H7 contamination of leafy greens was examined. In each of 2 years, leafy greens were planted in nine plots located 60, 120, and 180 m from a cattle feedlot (3 plots at each distance). Leafy greens (270) and feedlot manure samples (100) were collected six different times from June to September in each year. Both E. coli O157:H7 and total E. coli bacteria were recovered from leafy greens at all plot distances. E. coli O157:H7 was recovered from 3.5% of leafy green samples per plot at 60 m, which was higher (P < 0.05) than the 1.8% of positive samples per plot at 180 m, indicating a decrease in contamination as distance from the feedlot was increased. Although E. coli O157:H7 was not recovered from air samples at any distance, total E. coli was recovered from air samples at the feedlot edge and all plot distances, indicating that airborne transport of the pathogen can occur. Results suggest that risk for airborne transport of E. coli O157:H7 from cattle production is increased when cattle pen surfaces are very dry and when this situation is combined with cattle management or cattle behaviors that generate airborne dust. Current leafy green field distance guidelines of 120 m (400 feet) may not be adequate to limit the transmission of E. coli O157:H7 to produce crops planted near concentrated animal feeding operations. Additional research is needed to determine safe set-back distances between cattle feedlots and crop production that will reduce fresh produce contamination.  相似文献   
3.
This work investigates how functionalization of aluminium surfaces with natural type III Anti-Freeze Protein (AFP) affects the mechanism of heterogeneous ice nucleation. First the bulk ice nucleation properties of distilled water and aqueous solution of AFP were evaluated by differential scanning calorimetry. Then the modified surface was characterized by Secondary Ions Mass Spectroscopy (SIMS), Fourier Transform InfraRed (FTIR) spectroscopy and contact angle measurement. Freezing experiments were then conducted in which water droplets underwent a slow controlled cooling. This study shows that compared to uncoated aluminium, the anti-freeze proteins functionalized surfaces exhibit a higher and narrower range of freezing temperature. It was found that these proteins that keep living organisms from freezing in cold environment act in the opposite way once immobilized on surfaces by promoting ice nucleation. Some suggestions regarding the mechanism of action of the observed phenomena were proposed based on the Classical Nucleation Theory (CNT).  相似文献   
4.
目的:探讨280例胃食管反流病(GERD)的分布特点及危险因素。方法:对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果:不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者(z=-2.939,P=0.003,);汉族和维族患者占反流性食管炎和Barrett食管比例分别为42.4%、81_3%及56.5%、18.8%,其中汉族患者Barrett食管比例较高(X2=14.358,P=0.000);肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高(P〈0.001)。结论:GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。  相似文献   
5.
For fabrication of effective electrochemical biosensors, interfacing the biomolecular receptor with the underlying transducer represents a critical step. The actual approach taken depends on the tethering layer covering the transducer, which is typically either a conducting polymeric matrix, or a thin film, such as an alkanethiol monolayer. Non-specific immobilisation methods can be either covalent, or non-covalent affinity attachment, with multipoint electrostatic attachment of the sensing biomolecule to either a polyanionic or polycationic layer representing the most common approach. Many specific affinity immobilisation strategies exist, but the majority make use of one of two binding systems. The first relies on the specific and strong affinity between biotin and proteins of the avidin family, with both bioreceptor and transducer bearing pendant biotins and avidin used as the crosslinker. The second approach employs a metal chelating group on the transducer to which can be bound a polyhistidine tag present on the N- or C-terminus of the receptor protein and which can be introduced genetically, when the expression sequence for a recombinant proteins is designed.  相似文献   
6.
The aim of this study was to determine the effectiveness of natural flocculants to reduce solids and nutrient loads in dairy cow wastewater using solid–liquid separation; chitosan was used as a model. Its use efficiency and optimum application rate were determined using flushed dairy cow manure of varied strengths – 0.4%, 0.8%, 1.6%, and 3.2% total solids (TS) content. Treatments consisted of nine rates of chitosan. The flocculated manure was dewatered using 1-mm and 0.25-mm screens. Separation by screening alone was not effective; average efficiencies were about 60% for total suspended solids (TSS), 22% for total Kjeldahl nitrogen (TKN), and 26% for total phosphorus (TP). Mixing with chitosan before screening substantially increased separation. At optimum chitosan rate (0.5 g/L for the highest strength effluent), separation efficiencies were >95% for TSS, >73% for TKN, and >54% for TP. The results of this study indicate that natural flocculants such as chitosan are useful for the solid–liquid separation treatment of livestock wastewater.  相似文献   
7.

Background

This paper presents the study protocol for a pragmatic randomised controlled trial to evaluate the impact of a school based program developed to prevent teenage pregnancy. The program includes students taking care of an Infant Simulator; despite growing popularity and an increasing global presence of such programs, there is no published evidence of their long-term impact. The aim of this trial is to evaluate the Virtual Infant Parenting (VIP) program by investigating pre-conceptual health and risk behaviours, teen pregnancy and the resultant birth outcomes, early child health and maternal health.

Methods and Design

Fifty-seven schools (86% of 66 eligible secondary schools) in Perth, Australia were recruited to the clustered (by school) randomised trial, with even randomisation to the intervention and control arms. Between 2003 and 2006, the VIP program was administered to 1,267 participants in the intervention schools, while 1,567 participants in the non-intervention schools received standard curriculum. Participants were all female and aged between 13-15 years upon recruitment. Pre and post-intervention questionnaires measured short-term impact and participants are now being followed through their teenage years via data linkage to hospital medical records, abortion clinics and education records. Participants who have a live birth are interviewed by face-to-face interview. Kaplan-Meier survival analysis and proportional hazards regression will test for differences in pregnancy, birth and abortion rates during the teenage years between the study arms.

Discussion

This protocol paper provides a detailed overview of the trial design as well as initial results in the form of participant flow. The authors describe the intervention and its delivery within the natural school setting and discuss the practical issues in the conduct of the trial, including recruitment. The trial is pragmatic and will directly inform those who provide Infant Simulator based programs in school settings.

Trial registration

ISRCTN24952438  相似文献   
8.
We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies.  相似文献   
9.
Timing and rate of seasonal zone formation in southern North Sea cod Gadus morhua otoliths was studied. Samples were taken from two time periods, representing low and high temperature regimes. Opaque zones were laid down between January and June, in contrast with the pattern described in other published studies. Translucent zone formation started earlier in the warmer period, corresponding to peak annual sea surface temperatures, and a period of slow body growth and low metabolic activity. Translucent zone formation, however, continued once temperatures decreased and growth rate increased. It is hypothesized that translucent zone formation is triggered at a threshold of metabolic stress, and that the combined energetic requirements of reproduction, growth and migration may maintain translucent zone formation even if feeding conditions improve. Higher temperatures had a significant negative effect on the rate of translucent zone deposition, but caused a slight increase in opaque zone formation rate. The findings of this study indicate that historical otolith collections could provide key inputs into future phenological studies to improve the understanding of climate change impacts and the dynamics of otolith structure.  相似文献   
10.
Concern has greatly increased about the potential for contamination of water, food, and air by pathogens present in manure. We evaluated pathogen reduction in liquid swine manure in a multi-stage treatment system where first the solids and liquid are separated with polymer, followed by biological nitrogen (N) removal using nitrification and denitrification, and then phosphorus (P) extraction through lime precipitation. Each step of the treatment system was analyzed for Salmonella and microbial indicators of fecal contamination (total coliforms, fecal coliforms, and enterococci). Before treatment, mean concentrations of Salmonella, total coliforms, fecal coliforms, and enterococci were 3.89, 6.79, 6.23 and 5.73 log(10) colony forming units (cfu)/ml, respectively. The flushed manure contained 10,590 mg/l TSS, 8270 mg/l COD, 688 mg/l TKN and 480 mg/l TP, which were reduced >98% by the treatment system. Results showed a consistent trend in reduction of pathogens and microbial indicators as a result of each step in the treatment system. Solid-liquid separation decreased their concentrations by 0.5-1 log(10). Additional biological N removal treatment with alternating anoxic and oxic conditions achieved a higher reduction with average removals of 2.4 log(10) for Salmonella and 4.1-4.5 log(10) for indicator microbes. Subsequent P treatment decreased concentration of Salmonella and pathogen indicators to undetectable level (<0.3 log(10) cfu/ml) due to elevated process pH (10.3). Our results indicate that nitrification/denitrification treatment after solids separation is very effective in reducing pathogens in liquid swine manure and that the phosphorus removal step via alkaline calcium precipitation produces a sanitized effluent which may be important for biosecurity reasons.  相似文献   
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