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Objective To compare the cardiopulmonary effects and sensory blockade of epidural bupivacaine and ropivacaine. Study Design Prospective randomized study. Animals Six young adult medium‐sized crossbred dogs weighing 25.7 ± 7.1 kg. Method Dogs were chronically implanted with a lumbosacral epidural catheter. Acepromazine sedated dogs received all treatments: 0.5% bupivacaine at 0.14 mL kg?1 (LB5) or 0.22 mL kg?1 (HB5); 0.5% ropivacaine at 0.14 mL kg?1 (LR5) or 0.22 mL kg?1 (HR5); 0.75% bupivacaine at 0.22 mL kg?1 (HB7.5) or 0.75% ropivacaine at 0.22 mL kg?1 (HR7.5). Loss of sensation was tested at the level of the perineum, hind toe webs, flank, and caudodorsal rib areas before injection, and post‐injection (PI) up to 150 minutes PI. Systemic arterial blood pressure and heart rate were recorded before injection, and every 10 minutes PI until 150 minutes PI. Arterial blood gas analyses were performed prior to injection, and at 30, 60 and 150 minutes PI. Results No statistical differences existed between groups for the cardiopulmonary data or time to onset of block. Group HR7.5 had lower systolic (10–70 minutes PI) and diastolic (10–70 minutes PI) blood pressures and group HR5 had lower mean (10–90 minutes PI) and diastolic (10–90 minutes PI) blood pressures compared to baseline. Heart rate was lower compared to baseline in groups LR5 and HB7.5. A significant, but mild metabolic acidosis developed in groups LR5 and HB7.5 (150 minutes PI). No differences were present for the duration of block between groups, but duration of block in the dorsocaudal rib area was shorter in group HR5 compared to HR7.5. Conclusion Epidural ropivacaine and bupivacaine at the doses used have mild effects on the cardiopulmonary system, and extent of block are similar. Clinical Relevance The 0.75% concentration of bupivacaine and ropivacaine at 0.22 mL kg?1 appeared to contribute to greater success of block (>80%) at dermatomes L5–L7.  相似文献   
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Laboratory experiments were carried out to investigate bioclogging on three types of online emitters using synthetic wastewater filtered at 10 μm (COD = 200 mg L?1). The three types of emitters were as follows: non-pressure-compensating emitters delivering 2 L h?1 (NPC2), non-pressure-compensating emitters delivering 4 L h?1 (NPC4) and pressure-compensating emitters delivering 2.2 L h?1 (PC). They were plugged on two parallel pipe diameters (16 and 20 mm). Emitter performance was followed by flow rate measurements. The results showed that PC emitters seemed to be more sensitive to clogging than NPC emitters. Biofilm was observed mainly on NPC flow paths and PC membranes; its presence was also confirmed by the assessment of different water quality parameters such as total organic carbon and pH. Experimental results compared with a model designed with computational fluid dynamics Software (ANSYS Fluent®) showed relations between biofilm development and velocity distribution on NPC flow paths. Finally, pipe diameter also appeared to be a parameter inducing emitter clogging.  相似文献   
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The quality of information presented on health‐related websites—in terms of comprehensiveness, accuracy and consistency—is a public health concern. To date, the consistency of information across Canadian websites devoted to Lyme disease (LD) prevention has not been evaluated. The first aim of this study was to describe the contents and recommendations of LD prevention websites provided by two types of Canadian organizations: government (n = 3) and patient groups (n = 3). A second objective was to analyse the level of convergence among these websites in terms of their prevention‐related content. Initial coding of the content resulted in information segments grouped into 114 subthemes related to nine overarching themes: tick habitat suitability, risk period, transmission, personal protection, peridomestic environmental management, tick identification and removal, early symptoms, testing and diagnosis and preventive treatment. Comparative content analyses were performed both within and between the content of websites of the two organization types. The themes most frequently addressed by both organization types were personal protection (20% of the prevention‐related content in patient group websites and 22% of the prevention‐related content in government websites), transmission (12% and 16%, respectively) and tick identification and removal (19% and 15%, respectively). Government websites’ information was generally convergent with that of patient group websites (four highly convergent themes, three moderately convergent and two divergent). Nevertheless, of particular concern were divergent messages and inaccurate information found on 11 subthemes out of 103. Examples included other possible modes of transmission and the ineffectiveness of DEET insect repellent. These results suggest the need for public health and health communications research on the issue of the quality of LD prevention information found on the Internet.  相似文献   
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Introduction   

Tree breeding is giving an increasing attention to wood properties in order to better fit the requirements of the saw, board, pulp and paper industries. In particular, it has been reported that lignin and cellulose content display moderate to high heritabilities making them prime candidates for genetic improvement of wood chemistry. Moreover, these traits have been shown to be negatively correlated at both phenotypic and genetic levels. However, they have generally been evaluated against a narrow genetic background, and little is known about their correlations with mandatory selection criteria such as growth and straightness.  相似文献   
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A 6-yr-old male Vancouver Island marmot (Marmota vancouverensis) presented for poor hibernation, weight loss, and symmetric trunk alopecia. An abdominal interstitial cell tumor was identified and surgically removed. Serum levels of estrogen were markedly elevated before surgery and decreased after tumor removal, indicating that the tumor had been functionally secretory. Nine months later, the marmot presented with respiratory stridor. A large boney nasal mass was identified radiographically and evaluated by computed tomography (CT) prior to surgical debulking. The marmot did not recover from anesthesia. Pathologic findings included a nasal osteosarcoma with lysis of the cribriform plate, and endocardial fibrosis with degenerative changes within the adjoining myocardium. This is the first known report of nasal osteosarcoma and interstitial tumor in a Vancouver Island marmot.  相似文献   
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