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81.
Concern about emerging and re-emerging diseases plays an increasing role in conservation and management of both captive and free-ranging nonhuman primates (NHPs). Managers and policy makers must formulate conservation plans in an arena plagued by uncertainty, complexity, emotion, and politics. The risk analysis paradigm provides a framework that brings together scientists and policy experts to make better decisions for both people and animals. Risk analysis is a multidisciplinary, science-based process that provides an organized and logical approach for incorporating scientific information into policy development in the real world. By blending four specific goal-oriented stages-hazard identification, risk assessment, risk management, and risk communication-one can logically assess the probability that an adverse event, such as the introduction of an emerging disease into a na?ve population, will occur. The following is a review of this process as it pertains to NHP conservation and risks associated with infectious diseases.  相似文献   
82.

Background

The exhaled nitric oxide (eNO) signal is a marker of inflammation, and can be partitioned into proximal [J''awNO (nl/s), maximum airway flux] and distal contributions [CANO (ppb), distal airway/alveolar NO concentration]. We hypothesized that J''awNO and CANO are selectively elevated in asthmatics, permitting identification of four inflammatory categories with distinct clinical features.

Methods

In 200 consecutive children with asthma, and 21 non-asthmatic, non-atopic controls, we measured baseline spirometry, bronchodilator response, asthma control and morbidity, atopic status, use of inhaled corticosteroids, and eNO at multiple flows (50, 100, and 200 ml/s) in a cross-sectional study design. A trumpet-shaped axial diffusion model of NO exchange was used to characterize J''awNO and CANO.

Results

J''awNO was not correlated with CANO, and thus asthmatic subjects were grouped into four eNO categories based on upper limit thresholds of non-asthmatics for J''awNO (≥ 1.5 nl/s) and CANO (≥ 2.3 ppb): Type I (normal J''awNO and CANO), Type II (elevated J''awNO and normal CANO), Type III (elevated J''awNO and CANO) and Type IV (normal J''awNO and elevated CANO). The rate of inhaled corticosteroid use (lowest in Type III) and atopy (highest in Type II) varied significantly amongst the categories influencing J''awNO, but was not related to CANO, asthma control or morbidity. All categories demonstrated normal to near-normal baseline spirometry; however, only eNO categories with increased CANO (III and IV) had significantly worse asthma control and morbidity when compared to categories I and II.

Conclusions

J''awNO and CANO reveal inflammatory categories in children with asthma that have distinct clinical features including sensitivity to inhaled corticosteroids and atopy. Only categories with increase CANO were related to poor asthma control and morbidity independent of baseline spirometry, bronchodilator response, atopic status, or use of inhaled corticosteroids.  相似文献   
83.
猪源肠球菌的分离及生物特性的初报   总被引:4,自引:0,他引:4  
本研究从猪粪便中分离了肠球菌两珠,经菌种鉴定两珠菌均为屡肠球菌。其生物特性的研究表明:可耐受15的胆盐和6%NaCI高盐,在pH3.0条件下可存活,对绝大多数抗生素耐药。  相似文献   
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Personnel in medical, veterinary or research laboratories may be exposed to a wide variety of pathogens that range from deadly to debilitating. For some of these pathogens, no treatment is available, and in other cases the treatment does not fully control the disease. It is important that personnel in laboratories that process human or microbiological specimens follow universal precautions when handling tissues, cells, or microbiological specimens owing to the increasing numbers of individuals infected with hepatitis C and HIV in the US and the possibility that an individual may be asymptomatic when a specimen is obtained. Similar precautions must be followed in laboratories that use animal tissues owing to the possibility of exposure to agents that are pathogenic in humans. Personnel with conditions associated with immunosuppression should evaluate carefully whether or not specific laboratory environments put them at increased risk of disease. We offer here some general approaches to identifying biohazards and to minimizing the potential risk of exposure. The issues discussed can be used to develop a general safety program as required by regulatory or accrediting agencies, including the Occupational Safety and Health Administration.  相似文献   
86.
Excessive flexion and internal rotation of the hip is a common gait abnormality among individuals with cerebral palsy. The purpose of this study was to examine the influence of hip flexion on the rotational moment arms of the hip muscles. We hypothesized that flexion of the hip would increase internal rotation moment arms and decrease external rotation moment arms of the primary hip rotators. To test this hypothesis we measured rotational moment arms of the gluteus maximus (six compartments), gluteus medius (four compartments), gluteus minimus (three compartments) iliopsoas, piriformis, quadratus femoris, obturator internus, and obturator externus. Moment arms were measured at hip flexion angles of 0, 20, 45, 60, and 90 degrees in four cadavers. A three-dimensional computer model of the hip muscles was developed and compared to the experimental measurements. The experimental results and the computer model showed that the internal rotation moment arms of some muscles increase with flexion; the external rotation moment arms of other muscles decrease, and some muscles switch from external rotation to internal rotation as the hip is flexed. This trend toward internal rotation with hip flexion was apparent in 15 of the 18 muscle compartments we examined, suggesting that excessive hip flexion may exacerbate internal rotation of the hip. The gluteus maximus was found to have a large capacity for external rotation. Enhancing the activation of the gluteus maximus, a muscle that is frequently underactive in persons with cerebral palsy, may help correct excessive flexion and internal rotation of the hip.  相似文献   
87.
Mononephrectomized rats were given 1% NaCl solution to drink; half of them received 1 mg/day of 19-oxo-11 deoxycorticosterone acetate (19-oxo-DOCA) in sesame oil subcutaneously and half received only the oil for a period of four weeks. The steroid had no effect upon saline intake, systolic blood pressure, growth or the size of adrenals, hearts or kidneys, although it did produce hypernatremia and hypokalemia. The discrepancy between a demonstrable mineralocorticoid effect without blood pressure elevation awaits elucidation.  相似文献   
88.
Fibulin is a 100-kDa calcium-binding, extracellular matrix (ECM), and plasma glycoprotein (Argraves et al., Cell 58, pp. 623-629, 1989; Argraves et al., J. Cell Biol. 111, 3155-3164). Immunoprecipitation analysis showed that antibodies against human fibulin react with an avian isoform (M(r) 100,000). The spatial and temporal distribution of fibulin was examined in the early avian embryo using immunofluorescence microscopy. In stage 15-22 quail embryos fibulin is a constituent of most basement membranes. Areas undergoing epithelial-mesenchymal transitions such as the endocardial cushions, developing myotomes, and neural crest display especially prominent immunostaining. In the early heart fibulin expression was most pronounced in the cardiac jelly at sites where endocardial cushion cells begin the migrations that lead to the formation of valvular and septal primordia. Laser scanning confocal microscopy showed extensive extracellular accumulations of fibulin on the surface of endocardial mesenchyme cells that were motile at the time of fixation (stage 19). These data suggest that enhanced deposition of fibulin at sites of epithelial-mesenchymal transitions may influence cell behavior.  相似文献   
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