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101.
Objectives To document the equine perioperative mortality rate and to highlight any factor associated with an increased risk of death up to 7 days after anaesthesia. Study design A prospective observational epidemiological multicentre study. Methods Data were recorded from all equidae undergoing general anaesthesia in 62 clinics. Power calculations indicated that 45 000 cases were required to detect the significance of important variables. Details of each horse, operation, anaesthetic agents and clinic personnel were recorded. Outcome at 7 days was recorded as: alive, put to sleep (PTS) or dead. Data were analysed by a standard multilevel logistic regression approach, considering the effects of clustering at the level of clinic. Results Data were collected from 41 824 cases over 6 years. A total of 39 025 (93.3%) were alive on day 7 and 785 were dead giving an overall death rate of 1.9% (95% CI: 1.8–2.0) and 2014 (4.8%) were PTS. About 5846 horses undergoing emergency abdominal surgeries (‘colics’) were excluded from subsequent analyses. A total of 35 107 ‘noncolic’ horses were alive at 7 days and 328 dead giving a death rate for noncolics of 0.9% (95% CI: 0.8–1.0). Five hundred and forty‐three (1.5%) noncolic horses classified PTS were excluded from further analyses. There were 109 (33%) deaths from cardiac arrest or post‐operative cardiovascular collapse, with 107 (32%) from fractures and myopathies. Fracture repair, out of hours surgery, and age below 1 month was associated with increased risk of dying whereas the use of acepromazine and intravenous anaesthetic agent maintenance of anaesthesia was associated with reduced risk. Conclusions A number of potential contributors to the high risk of anaesthetic‐related mortality have been identified. Further investigation of the underlying mechanism for their apparent harmful effects and development of alternative techniques is merited.  相似文献   
102.
103.
 田间抗性监测发现了大麦云纹斑病菌新型的抗性菌株,这类菌株对苯并咪唑类(多菌灵)、Phenylcarbamate(乙霉威)及三唑类(三唑醇)表现多重抗性,先前发现的多菌灵抗药性菌株均是在β-维管蛋白基因的198位点出现等位基因的突变,而新发现的菌株则仅在200位点(TTC)由苯并氨酸转变成赖氨酸(TAC)而导致对3种药剂的抗性。温室试验证明,这类菌株的致病性和野生敏感菌的致病性几乎一致,说明大麦云纹斑病菌对杀菌剂抗药性的发展与致病性之间没有相关性。  相似文献   
104.
Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet.  相似文献   
105.
The use of electrophoretic markers in seed orchard research   总被引:5,自引:0,他引:5  
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106.
Chromobacterium violaceum is a saprophyte of soil and water in tropical and subtropical environments that is associated with rare but highly fatal infections in animals and humans. Systemic infection was diagnosed in two critically ill dogs from Florida. Fever was absent in both dogs. Both dogs were treated surgically and provided with intensive care, but only one survived. The identification of characteristic, violet-pigmented bacterial colonies on routine microbial cultures should alert microbiologists and clinicians to the likelihood of this dangerous pathogen. Because of the rapidly progressive nature of this infection, empirical antibiotic administration with fluoroquinolones should be employed pending susceptibility testing.  相似文献   
107.
Reefs of the deep: the biology and geology of cold-water coral ecosystems   总被引:2,自引:0,他引:2  
Coral reefs are generally associated with shallow tropical seas; however, recent deep-ocean exploration using advanced acoustics and submersibles has revealed unexpectedly widespread and diverse coral ecosystems in deep waters on continental shelves, slopes, seamounts, and ridge systems around the world. Advances reviewed here include the use of corals as paleoclimatic archives and their biogeological functioning, biodiversity, and biogeography. Threats to these fragile, long-lived, and rich ecosystems are mounting: The impacts of deep-water trawling are already widespread, and effects of ocean acidification are potentially devastating.  相似文献   
108.
Objective: To determine the prevalence of radiographic signs of degenerative joint disease (DJD) in a randomly selected sample of domestic cats. Study Design: Prospective observational study. Animals: Client‐owned cats. Methods: Cats (n=100) from a single practice and equally distributed across 4 age groups (0–5; 5–10; 10–15, and 15–20 years old) were randomly selected (regardless of heath status) and sedated for orthogonal radiographic projections of all joints and the spine. Quasi‐Poisson regression analysis was used to investigate the relationship between patient demographics, blood biochemistry, hematologic and urine analysis variables, and DJD severity. Results: Most (92%) cats had radiographic evidence of DJD; 91% had at least 1 site of appendicular DJD and 55% had ≥1 site of axial column DJD. Affected joints in descending order of frequency were hip, stifle, tarsus, and elbow. The thoracic segment of the spine was more frequently affected than the lumbosacral segment. Although many variables were significantly associated with DJD, when variables were combined, only the association between age and DJD was significant (P<.0001). For each 1‐year increase in cat age, the expected total DJD score increases by an estimated 13.6% (95% confidence interval: 10.6%, 16.8%). Conclusion: Radiographically visible DJD is very common in domesticated cats, even in young animals and is strongly associated with age. Clinical Relevance: DJD is a common disease of domesticated cats that requires further investigation of its associated clinical signs.  相似文献   
109.
The case histories of 8 dogs with spinal pain and neurologic deficits associated with vertebral plasma cell tumor are reviewed. Four dogs had solitary plasmacytoma, 3 had multiple myeloma, and 1 dog had 2 vertebral lesions with no evidence of disseminated disease. Four dogs were treated: 2 with multiple myeloma received chemotherapy only and survived 17 and 26 months, respectively. Two dogs with solitary plasmacytomas of the spine had chemotherapy and radiotherapy: the 1st survived 4 months and was euthanized after developing radiation myelopathy; the 2nd survived 65 months before developing multiple myeloma. The diagnosis of solitary plasmacytoma of the spine versus multiple myeloma is discussed.  相似文献   
110.
Our objectives were to examine the effects of prerigor excision and rapid chilling vs. conventional carcass chilling of two muscles on proteolysis and tenderness during the postmortem storage, as well as the effects of fast and slow rates of cooking on myofibrillar characteristics and tenderness. The longissimus thoracis (LT) and triceps brachii (TB), long head muscles were removed 45 min after exsanguination from the left side of 12 carcasses and chilled in an ice bath to induce cold shortening (excised, rapidly chilled). At 24 h postmortem, the corresponding muscles were removed from the right side (conventionally chilled). All muscles were cut into 2.54-cm-thick steaks and assigned to one of two postmortem times (1 or 14 d), and to raw and cooking treatments. Steaks were cooked at 260 degrees C (FAST) or 93 degrees C (SLOW) in a forced-air convection oven to an internal temperature of 70 degrees C. Cooking loss, cooking time, and Warner-Bratzler shear force (WBSF) were measured on cooked steaks. Sarcomere length (SL) and the extent of proteolysis of desmin were measured on raw and cooked steaks. As expected, the excised, rapidly chilled muscles had a much more rapid (P < 0.05) temperature decline than those that were conventionally chilled. The excised, rapidly chilled treatment resulted in shorter (P < 0.05) SL, and SL was shorter (P < 0.05) in LT than in TB steaks. Raw steaks had longer (P < 0.05) SL than cooked steaks, regardless of chilling treatment. The FAST cooking resulted in shorter (P < 0.05) SL than SLOW cooking in conventionally chilled steaks, but cooking rate had no effect (P > 0.05) on SL of rapidly chilled steaks. Generally, TB steaks required longer (P < 0.05) cooking times and had higher (P < 0.05) cooking losses than LT steaks, and FAST-cooked steaks had greater (P < 0.05) cooking losses than SLOW-cooked steaks. Rapidly chilled steaks had less (P < 0.05) degradation of desmin than conventionally chilled steaks (31 vs. 41%). Aging for 14 d increased (P < 0.05) desmin degradation. Rapid chilling of muscles resulted in much higher (P < 0.05) WBSF values, whereas aging resulted in lower (P < 0.05) WBSF values. The SLOW-cooked TB steaks were more tender (P < 0.05) than FAST-cooked TB steaks and LT steaks cooked at either rate. Excised, rapidly chilled muscles underwent proteolysis, but it occurred at a slower rate during the first 24 h postmortem than it did in conventionally chilled muscles. Cooking rate did not affect tenderness of LT steaks, but SLOW cooking resulted in more tender TB steaks.  相似文献   
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