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81.
A comprehensive phylogeny of beetles reveals the evolutionary origins of a superradiation 总被引:1,自引:0,他引:1
Hunt T Bergsten J Levkanicova Z Papadopoulou A John OS Wild R Hammond PM Ahrens D Balke M Caterino MS Gómez-Zurita J Ribera I Barraclough TG Bocakova M Bocak L Vogler AP 《Science (New York, N.Y.)》2007,318(5858):1913-1916
Beetles represent almost one-fourth of all described species, and knowledge about their relationships and evolution adds to our understanding of biodiversity. We performed a comprehensive phylogenetic analysis of Coleoptera inferred from three genes and nearly 1900 species, representing more than 80% of the world's recognized beetle families. We defined basal relationships in the Polyphaga supergroup, which contains over 300,000 species, and established five families as the earliest branching lineages. By dating the phylogeny, we found that the success of beetles is explained neither by exceptional net diversification rates nor by a predominant role of herbivory and the Cretaceous rise of angiosperms. Instead, the pre-Cretaceous origin of more than 100 present-day lineages suggests that beetle species richness is due to high survival of lineages and sustained diversification in a variety of niches. 相似文献
82.
Latifa Khenissi Gwen Covey-Crump Toby G. Knowles Joanna Murrell 《Veterinary anaesthesia and analgesia》2017,44(3):452-460
Objective
To investigate whether the use of a heat and moisture exchanger (HME) preserves body temperature in dogs weighing <10 kg anaesthetised for magnetic resonance imaging (MRI).Study design
Prospective, randomised, clinical trial.Animals
Thirty-one client-owned dogs.Methods
Dogs were assigned randomly to a treatment group [HME (n = 16) or no HME (n = 15)]. Dogs were pseudorandomised according to the premedication they were administered, either dexmedetomidine or no dexmedetomidine. Induction agents were not standardised. General anaesthesia was maintained with isoflurane vaporised in 100% oxygen delivered using a T-piece and a fresh gas flow of 600 mL kg?1 minute?1. Rectal temperature was measured before premedication (T1), after induction (T2), before moving to the MRI unit (T3) and at the end of the MRI scan (T4). Ambient temperatures were measured in the induction room, outside and inside the MRI unit. Data were analysed using a general linear model with T4 as the outcome variable. Linear correlations were performed between T1, T2, T3 and T4, and variables that predicted T4 were investigated.Results
Sex, age and body mass were not significantly different between groups. There were no significant differences in rectal temperature between groups at any time point (group with HME at the end of MRI = 36.3 ± 1.1 °C; group with no HME at the end of MRI = 36.2 ± 1.4 °C) but at the end of the MRI, dogs administered dexmedetomidine (36.6 ± 0.7 °C) had a higher rectal temperature compared with dogs not administered dexmedetomidine (35.9 ± 1.6 °C) for premedication. Rectal temperature varied directly with ambient temperature in MRI scanning room and inversely with anaesthetic duration.Conclusions and clinical relevance
Using an HME did not alter body temperature in dogs weighing <10 kg undergoing an MRI, but including dexmedetomidine in the premedication regimen seemed to preserve the body temperature during anaesthesia. 相似文献83.
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ObjectiveTo measure the level of agreement between Doppler measured (DOP) arterial blood pressure (ABP) in the forelimb and directly measured (DIR) auricular systolic ABP (SAP) and mean ABP (MAP) in isoflurane-anaesthetized rabbits.Study designProspective clinical study.AnimalsData were analysed from 17 of 24 healthy rabbits, weighing 1.3–2.8 kg.MethodsRabbits were anaesthetized for neutering using a standardized protocol. A 26G catheter placed in an auricular artery was connected via heparinised saline filled non-compliant tubing (regularly flushed) to a calibrated pressure transducer (zeroed level with the thoracic inlet) to obtain DIR ABP. A cuff was placed proximal to the carpus (approximately level with the thoracic inlet) and a Doppler transducer sited over the dorsal carpal branch of the radial artery to obtain DOP ABP. Simultaneous DIR and DOP ABP recordings were made every 5–10 minutes during anaesthesia. Agreement was assessed as described by Bland JM &; Altman (2007).ResultsMean ± SD cuff width: limb circumference ratio was 0.50 ± 0.04. Mean between-method differences ± SD, DIR SAP- DOP and DIR MAP- DOP, were +1 ± 8 and ?13 ± 8 mmHg respectively. The 95% limits of agreement between DIR SAP and DOP and between DIR MAP and DOP were ?14 to +17 and ?28 to +2 mmHg respectively. Differences between DIR SAP and DOP were ≤10 mmHg 85% of the time. Defining hypotension as either DIR SAP < 80 mmHg or DIR MAP < 60 mmHg, and taking DOP ABP of <80 mmHg to indicate hypotension, sensitivity and specificity were 92% and 67% respectively.ConclusionsGood agreement was found between DIR SAP and DOP. Doppler measurements below 80 mmHg are a reliable indicator of arterial hypotension.Clinical relevanceDOP is acceptable for monitoring ABP in isoflurane-anaesthetized rabbits and is useful for detection of hypotension. 相似文献
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87.
BACKGROUND: Bruchus rufimanus is a serious pest of field beans. The objective here was to develop a semiochemical‐baited trapping system to facilitate monitoring of the pest. RESULTS: Volatile compounds that were electrophysiologically active with the antennae of B. rufimanus females were identified from headspace samples of Vicia faba flowers and from male B. rufimanus. Selected headspace samples and synthetic compounds were tested in olfactometer bioassays. The semiochemicals were then formulated in lures for traps and evaluated in a field trapping experiment. Cone traps baited with a three‐component blend of floral volatiles, releasing (R)‐linalool (17.7 mg day?1), cinnamyl alcohol (0.4 mg day?1) and cinnamaldehyde (0.77 mg day?1), caught significantly more of both sexes of B. rufimanus than unbaited control traps. A male volatile, 1‐undecene, was EAG active with female antennae. It was attractive to females in an olfactometer, indicating that it is a sex pheromone. However, in the field it only enhanced trap catches if it was released together with the floral volatiles. CONCLUSION: The blends of semiochemicals identified were shown to be attractive in cone traps under field conditions. The prototype trapping system developed could be used as a monitoring tool to determine infestation levels of B. rufimanus in bean fields. Copyright © 2011 Society of Chemical Industry 相似文献
88.
Objective: To assess the reliability of radiographic measurement of angle of lateral opening (ALO) and angle of version of BFX acetabular cups. Study Design: In vitro radiographic study. Sample Population: BFX cups (24, 28, and 32 mm). Methods: Total hip replacement constructs (cups, 17 mm femoral head and a #7 CFX stem) were mounted on an inclinometer. Ventrodorsal radiographs were obtained with ALO varying between 21° and 70° and inclination set at 0°, 10°, 20°, and 30°. Radiographs were randomized using a random sequence generator. Three observers blinded to the radiograph order assessed ALO using 3 methods: (1) an ellipse method based on trigonometry; (2) using a measurement from the center of the femoral head to the truncated surface of the cup; (3) by visual estimation using a reference chart. Version was measured by assessing the ventral edge of the truncated surface. Results: ALO methods 2 and 3 were accurate and precise to within 10° and were significantly more accurate and precise than method 1 (P<.001). All methods were significantly less accurate with increasing inclination. Version measurement was accurate and precise to within 7° with 0–20° of inclination, but significantly less accurate with 30° of inclination. Conclusions: Methods 2 and 3, but not method 1, were sufficiently accurate and precise to be clinically useful. Version measurement was clinically useful when inclination was ≤20°. 相似文献
89.
Roch SP Clements DN Mitchell RA Downes C Gemmill TJ Macias C McKee WM 《The Journal of small animal practice》2008,49(3):117-126
OBJECTIVES: To report the complications encountered following tarsal arthrodesis surgery with bone plate fixation and describe the previously unreported complication of plantar necrosis. METHODS: Medical records of 40 dogs that had been treated by tarsal arthrodesis with bone plate fixation were reviewed to determine the major and minor complications and the associated risk factors. RESULTS: The major complication rate was 32.5 per cent and the minor complication rate was 42.5 per cent. Pantarsal arthrodeses had a higher major complication rate than partial tarsal arthrodeses. Plantar necrosis was the most common major complication and occurred in 15 per cent of cases. Plantar necrosis occurred more frequently when a bone plate was applied to the medial aspect of the hock, and only occurred in cases where tarsometatarsal joint arthrodesis was performed. CLINICAL SIGNIFICANCE: Plantar necrosis is a catastrophic complication that may be associated with injury to the dorsal pedal artery or perforating metatarsal artery. Application of a bone plate to the medial aspect of the hock should be performed with care during tarsal arthrodesis, particularly where the tarsometatarsal joint is debrided of cartilage. Strict attention to surgical technique and proper postoperative coaptation is critical to reduce the potential for complications with tarsal arthrodesis. 相似文献
90.