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1.
Broiler (meat) chickens have been subjected to intense genetic selection. In the past 50 years, broiler growth rates have increased by over 300% (from 25 g per day to 100 g per day). There is growing societal concern that many broiler chickens have impaired locomotion or are even unable to walk. Here we present the results of a comprehensive survey of commercial flocks which quantifies the risk factors for poor locomotion in broiler chickens. We assessed the walking ability of 51,000 birds, representing 4.8 million birds within 176 flocks. We also obtained information on approximately 150 different management factors associated with each flock. At a mean age of 40 days, over 27.6% of birds in our study showed poor locomotion and 3.3% were almost unable to walk. The high prevalence of poor locomotion occurred despite culling policies designed to remove severely lame birds from flocks. We show that the primary risk factors associated with impaired locomotion and poor leg health are those specifically associated with rate of growth. Factors significantly associated with high gait score included the age of the bird (older birds), visit (second visit to same flock), bird genotype, not feeding whole wheat, a shorter dark period during the day, higher stocking density at the time of assessment, no use of antibiotic, and the use of intact feed pellets. The welfare implications are profound. Worldwide approximately 2 x 10(10) broilers are reared within similar husbandry systems. We identify a range of management factors that could be altered to reduce leg health problems, but implementation of these changes would be likely to reduce growth rate and production. A debate on the sustainability of current practice in the production of this important food source is required.  相似文献   

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STRONGYLOIDIASIS, WHICH IS CAUSED by the nematode Strongyloides stercoralis, is a common and persistent infection, particularly in developing countries. In the setting of compromised cellular immunity, it can result in fulminant dissemination with case-fatality rates of over 70%. The majority of new Canadian immigrants come from countries where Strongyloides is highly endemic; therefore, the burden of Strongyloides may be underappreciated in Canada. Because early diagnosis and therapy can have a marked impact on disease outcome, screening for this infection should be considered mandatory for patients who have a history of travel or residence in a disease-endemic area and risk factors for disseminated disease (e.g., corticosteroid use and human T-lymphotropic virus type I infection). The following case is typical of a Strongyloides infection presenting to an infectious diseases service at a tertiary care hospital: A 50-year-old man who was originally from Cambodia but who had lived in Canada for the past 15 years presented with nausea and vomiting. His history was notable for arthritis, which was treated with prednisone, and type 2 diabetes mellitus. After admission, the patient became febrile and hypotensive. Blood cultures were positive for a gram-negative bacillus, and he was given ciprofloxacin and ceftriaxone. His respiratory status deteriorated, and Strongyloides larvae were incidentally noted on Gram stain and culture after bronchoalveolar lavage (Fig. 1). The patient was given 400 mg of albendazole twice a day and 15 mg of ivermectin once daily, but progressive respiratory failure followed and he died 3 weeks later.Open in a separate windowFig. 1: Strongyloides stercoralis larva tracks on a blood agar plate from the bronchoalveolar lavage of a patient with disseminated strongyloidiasis.This case exemplifies 2 key points. Foremost is that delays in establishing the diagnosis of strongyloidiasis can result in disseminated and fatal infection. Although the gastrointestinal tract is the primary site of Strongyloides infection, associated symptoms such as abdominal pain and intermittent diarrhea may be vague; if ignored by the clinician, the diagnosis may be made only upon dissemination and clinical deterioration of the patient. Second, eliciting an appropriate travel and migration history from patients and recognizing risk factors for disseminated infection are the essential epidemiologic clues for establishing early diagnosis. The purpose of this article is to highlight the risk factors and clinical presentation of strongyloidiasis and to provide a strategy for diagnosis and management. The goal is to raise awareness of this relatively common infection and thereby to facilitate early diagnosis and treatment of this potentially fatal but eminently curable disease.  相似文献   

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The mode of the cytotoxic activity of three benzo(c)fluorene derivatives was characterized. The observed morphological changes of lysosomes or variations of mitochondrial activity are assumed to be the consequence of cell protection against oxidative damage and/or the part of the damage process. To establish the relationship between the quantity of superoxide (O2*-) generated and the degree of damage resulting from O2*-, a simple system based on measurement of 3-(4-iodophenyl)-2-(4-nitrophenyl)-5-phenyltetrazolium chloride (INT) reductase activity in the presence of superoxide dismutase (SOD) was used. The functionality of the chosen battery of in vitro tests was proved using several known superoxide inducers: cyclosporin A (CsA) and benzo(a)pyrene (BP), as well as noninducers: citrinin (CT) and cycloheximide (CH). From the results followed that the cell growth tests are much better indices of toxicity than the other tests. The model system for the evaluation of the protective capacity of antioxidants against superoxide-induced cytotoxicity included simultaneous exposure of HeLa cells to cytotoxic drugs and to quercetin (Qe), an antioxidant of plant origin. The complete abolishment of the inhibition of cell proliferation and clonogenic survival was concluded to be due to the protective effect of the antioxidant. These observations correlated with the decrease of superoxide content as estimated by the INT-reductase assay in the presence of SOD using the same model system, as well as with the increase of intracellular SOD content and its activity.  相似文献   

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High-dose (75 mg/m2) cisplatin is baseline chemotherapy in lung cancer. To prevent nephrotoxicity, patients generally receive saline infusion on the day of chemotherapy prior to and following cisplatin (total of 3.5-4.0 liters during 3-4 hours). Despite these measures nephrotoxicity has remained frequent, especially among patients also suffering from cardiovascular disease or diabetes mellitus. Since 2005 several international recommendations have been formed about prevention of cisplatin nephrotoxicity. According to these recommendations: 1) renal function should not be evaluated by serum creatinine concentration; 2) evaluation of renal function should be based on calculated creatinine clearance (e.g. by the Cockcroft-Gault equation); 3) patients to be treated by high-dose cisplatin should be euvolemic and should have saline diuresis (urine NaCl concentration ~1%) of at least 100 ml/hour prior to, during and several days following the administration of cisplatin. Keeping these recommendations ensures prolonged cisplatin treatability of lung cancer patients. Moreover, decreased renal function will not limit the full dose administration of several other cytotoxic agents. Losonczy G, Máthé C, Müller V, Szondy K, Moldvay J. Incidence, risk factors and prevention of cisplatin-induced nephrotoxicity in patients with lung cancer.  相似文献   

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Background

The epidemiological and molecular characteristics of hepatitis C virus (HCV) infection in the general population have been poorly investigated in Africa. The aim of this study was to determine the prevalence, genotype distribution and epidemic history of HCV in the Gabonese general population.

Methods/Principal Findings

A total of 4042 sera collected from adults in 220 villages in all nine administrative areas of the country were screened for antibodies to HCV. HCV NS5B region sequencing was performed for molecular characterization and population genetic analyses. Of 4042 tested sera, 455 (11.2%) were positive. The seroprevalence of HCV varied significantly by administrative area, with the highest rate in Ogooué-Lolo province (20.4%) and the lowest in Ogooué-Maritine province (3.7%). History of parenteral injections, past hospital admission and age over 55 years were independent risk factors for HCV infection (p<0.0001). Phylogenetic analyses showed that 91.9% of the strains were genotype 4 (HCV-4), 5.7% genotype 1 and 2.2% genotype 2. HCV-4 strains were highly heterogeneous, with more than eight subtypes; subtype 4e predominated (57.3%). Coalescence analyses indicated that subtype 4e was the oldest, with an estimated most recent common ancestor of 1702 [95% CI, 1418–1884]. The epidemic profile indicated that it spread exponentially during the first part of the 20th century, probably by iatrogenic transmission.

Conclusions/Significance

These results confirm the endemicity of HCV subtype 4e in Gabon and show that its spread is due to a cohort effect, with previous, possibly iatrogenic events. More extensive epidemiological studies are needed to better characterize the route of transmission and the dissemination of HCV in Gabon.  相似文献   

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Longitudinal studies indicate that 20% of paediatric patients account for 80% of all admissions for diabetic ketoacidosis (DKA). The frequency of DKA peaks during adolescence and, although individuals generally go into remission, they may continue to have bouts of recurrent DKA in adulthood. The evidence for insulin omission being the behavioural precursor to recurrent DKA is reviewed and discussed. Thereafter the range of possible psychosocial causes is explored and the evidence for each discussed. Approaches to assessing the individual and their family to identify aetiology and therefore appropriate intervention are considered and treatment options reviewed. Finally, the paper examines potential risk factors for recurrent DKA, possible strategies for identifying these early and how to use these assessments to prevent subsequent recurrent DKA.  相似文献   

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Bone disorders such as osteopenia and osteoporosis have been recently reported in patients infected with the human immunodeficiency virus (HIV), but their etiology remains still unknown. The prevalence estimates vary widely among the different studies and can be affected by concomitant factors such as the overlapping of other possible conditions inducing bone loss as lypodystrophy, advanced HIV-disease, advanced age, low body weight or concomitant use of other drugs. All the reports at the moment available in the literature showed a higher than expected prevalence of reduced bone mineral density (BMD) in HIV-infected subjects both na?ve and receiving potent antiretroviral therapy compared to healthy controls. This controversial can suggest a double role played by both antiretroviral drugs and HIV itself due to immune activation and/or cytokines disregulation. An improved understanding of the pathogenesis of bone disorders can result in better preventative and therapeutic measures. However, the clinical relevance and the risk of fractures remains undefined in HIV-population. The clinical management of osteopenia and osteoporosis in HIV-infected subjects is still being evaluated. Addressing potential underlying bone disease risk factors (e.g., smoking and alcohol intake, use of corticosteroids, advanced age, low body weight), evaluating calcium and vitamin D intake, and performing dual x-ray absorptiometry in HIV-infected individuals who have risk factors for bone disease can be important strategies to prevent osteopenia and osteoporosis in this population. The administration of bisphosphonates (e.g., alendronate), with calcium and vitamin D supplementation, may be a reasonable and effective option to treat osteoporosis in these subjects.  相似文献   

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There are few little exact epidemiological data on the prevalence and incidence of latex allergy, partly because the diagnostic tools are unsatisfactory and partly because the epidemiological study planning often does not fulfill criteria of good praxis. On the basis of present data, latex allergy in normal population is low, under 1%. Known risk groups such as health care workers, atopic subjects, people with hand dermatitis, and especially spina bifida patients show higher prevalence numbers. The common serological cross-reactivity between latex and a great number of different fruits and vegetables is bound to common plant pathogenesis-related proteins and storage proteins. Despite positive serological tests, only about half of NRL-allergic subjects have clinical symptoms after eating cross-reacting foods.  相似文献   

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目的 分析眼科手术室患者感染危险因素,讨论感染风险管理对策。方法 回顾2017年7月至2018年8月我院眼科手术室患者的感染情况,分析感染危险因素并制定应对策略。结果 2017年7月至2018年8月我院共实施眼科手术1 987只眼,均未发生感染。空气污染,医疗器械污染,防控意识薄弱可能是患者发生感染的危险因素。结论 规范流程可以有效规避眼科手术感染,注重细节管理是预防眼科手术感染的关键。  相似文献   

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Arrhythmogenic cardiomyopathy (AC), also known as arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), is a hereditary disease characterised by ventricular arrhythmias, right ventricular and/or left ventricular dysfunction, and fibrofatty replacement of cardiomyocytes. Patients with AC typically present between the second and the fourth decade of life with ventricular tachycardias. However, sudden cardiac death (SCD) may be the first manifestation, often at young age in the concealed stage of disease. AC is diagnosed by a set of clinically applicable criteria defined by an international Task Force. The current Task Force Criteria are the essential standard for a correct diagnosis in individuals suspected of AC. The genetic substrate for AC is predominantly identified in genes encoding desmosomal proteins. In a minority of patients a non-desmosomal mutation predisposes to the phenotype. Risk stratification in AC is imperfect at present. Genotype-phenotype correlation analysis may provide more insight into risk profiles of index patients and family members. In addition to symptomatic treatment, prevention of SCD is the most important therapeutic goal in AC. Therapeutic options in symptomatic patients include antiarrhythmic drugs, catheter ablation, and ICD implantation. Furthermore, patients with AC and also all pathogenic mutation carriers should be advised against practising competitive and endurance sports.  相似文献   

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