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排序方式: 共有365条查询结果,搜索用时 31 毫秒
31.
Martin Kváč Michaela Kestřánová Martina Pinková Dana Květoňová Jana Kalinová Pavla Wagnerová Michaela Kotková Jiří Vítovec Oleg Ditrich John McEvoy Brianna Stenger Bohumil Sak 《Veterinary parasitology》2013,191(3-4):218-227
We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 μm (mean = 5.16) × 4.23–5.29 μm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250–4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species. 相似文献
32.
Corti Martina Cavalli Daniele Cabassi Giovanni Vigoni Antonio Degano Luigi Marino Gallina Pietro 《Precision Agriculture》2019,20(4):675-696
Precision Agriculture - The development of small unmanned aerial vehicles and advances in sensor technology have made consumer digital cameras suitable for the remote sensing of vegetation. In this... 相似文献
33.
Phenol oxidase and peroxidase activities in desert grassland soils at the Sevilleta Long Term Ecological Research site in central New Mexico (USA) are far greater than those of temperate soils. Activity is uniformly distributed across particles ranging from >1 mm to <38 μm and is unaffected by autoclaving, in contrast to hydrolase activities. The sorbed enzymes are readily extractable and inactivated by boiling. High soil pH, high stabilized oxidative enzyme activity, and carbonates create optimal conditions for degradation of phenols which increase decomposition potentials and limit soil organic matter accumulation. 相似文献
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35.
John BUCKERIDGE Tom KOÍ Jn SCHL
GL Adam TOMAOVÝCH Martina KOOV VESELSK 《Integrative zoology》2019,14(6):561-575
Fossil cephalopods are frequently encrusted by epibionts; however, determining whether encrustation occurred prior to or post‐mortem to the host, and whether the final environment of deposition corresponds to the habitat of encrustation is complex. The present paper describes cirripede epibionts, their calcareous bases and their attachment scars on 6 post‐mortem shells of Nautilus macromphalus, collected from deep water off New Caledonia. The cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph barnacles. Live cirripedes included a Metaverruca recta, with articulated opercular plates and organic tissue (on a shell that had been exposed on the sea floor for at least 150 years), and specimens of Hexelasma velutinum, one of which was partly attached to an internal surface of a shell. The disposition of verrucomorphs indicates that most Nautilus shells were colonized post‐mortem rather than during a floating stage. However, as cirripedes are known to have colonized living Nautilus, some Hexelasma, preserved only as calcareous eroded bases, may represent specimens that settled on a living Nautilus. The degree of bioerosion and discoloration induced by verrucomorph barnacles varies according to the surface preservation of Nautilus shells, with deeper and discolored traces preserved on old and degraded shells. Traces made by verrucomorphs described here are ellipsoidal and a new ichnotaxon, Anellusichnus ellipticus, is proposed to accommodate them. Importantly, verrucomorphs and other cirripede taxa with membranous bases that were attached to pristine shells may not leave any substantial scars, and, thus, will be difficult to detect in the fossil record. 相似文献
36.
Martina Mosing Dr med vet DECVAA Isabelle K. Iff Dr med vet DECVAA Wolfgang Nemetz MD 《Journal of Veterinary Emergency and Critical Care》2008,18(5):532-536
Objective – To describe general anesthesia and successful resuscitation of a dog developing asystole and apnea during extradural injection of local anesthetic and an opioid. Case Summary – A Beagle with a ruptured cranial cruciate was premedicated with acepromazine and methadone. Anesthesia was induced with propofol and, after endotracheal intubation, maintained using isoflurane in oxygen. During extradural injection of a mixture of lidocaine, bupivacaine, and morphine the dog developed apnea and asystole. Cardiopulmonary cerebral resuscitation was started promptly and the dog was successfully resuscitated. New Information Provided – Asystole and apnea are possible serious side effects of extradural anesthesia in dogs. With adequate monitoring and early detection successful resuscitation is possible. 相似文献
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OBJECTIVE: To investigate the onset and duration of neuromuscular blockade of rocuronium bromide and its associated haemodynamic effects at three doses in healthy horses. STUDY DESIGN: Prospective, randomized experimental study. ANIMALS: Seven adult horses aged 3-20 (mean 10.3) years and weighing 466 +/- 44 (mean +/- SD) kg. METHODS: Horses were anaesthetized three times with at least 2 weeks between. They were pre-medicated with 0.6 mg kg(-1) xylazine and 0.01 mg kg(-1) butorphanol i.v.. Anaesthesia was induced with 2.2 mg kg(-1) ketamine and 0.1 mg kg(-1) diazepam i.v.. Following orotracheal intubation anaesthesia was maintained with isoflurane in 100% oxygen. Intermittent positive pressure ventilation was initiated and the horses were ventilated at a respiratory rate (fr) of 4-8 breaths minute(-1). Neuromuscular function was monitored with an acceleromyograph. The peroneal nerve was stimulated with train-of-four (TOF) mode at 2 Hz every 15 seconds. Each horse received, in randomly assigned order, one of the three doses of rocuronium: 0.2 mg kg(-1) (D02), 0.4 mg kg(-1) (D04) or 0.6 mg kg(-1) (D06) i.v.. Lag time, onset time, time of no response, duration of action and the TOF ratio 0.7 and 0.9 were measured. Recovery time (T1(25-75)) was calculated. Vital parameters were recorded at 5-minute intervals on a standard anaesthetic record form. RESULTS: Rocuronium produced a dose-dependent duration of action in isoflurane-anaesthetized horses. 100% block was observed in D04 and D06 but not in D02, in which the maximum decrease of the first twitch of TOF attained was 91.5 +/- 16.5%. Time to T1(25) was 13.1 +/- 5.5 minutes, 38.6 +/- 10.1 minutes and 55 +/- 9.8 minutes in D02, D04 and D06 respectively. There was a significantly shorter time for TOFR 0.9 with 0.2 mg kg(-1) compared with 0.4 and 0.6 mg kg(-1) rocuronium. T1(25-75) in D04 and D6 was not statistically significantly different. Heart rate, systolic, diastolic and mean arterial blood pressure increased slightly during the observation period. CONCLUSION: Rocuronium is an effective nondepolarizing muscle relaxant in horses under isoflurane anaesthesia. It had a dose-dependent onset and duration of action. Rocuronium did not produce significant changes in the measured cardiovascular parameters. 相似文献
39.
This article analyses motivations and attitudes of small-scale forest owners in the Czech Republic towards joining associations. The research is a follow-up to a field investigation performed within the National Forest Programme II for 2007–2013 in the Vyso?ina region in 2010. The present research was carried out in the Pilsen region in 2012 and the Central Bohemia region in 2015, applying the same method of investigation as in 2010—a questionnaire survey. The findings are based on the results of all three surveys and supported by the analysis of legal and forestry-related documents concerning financial subsidies for forest owners’ associations. The study has revealed reluctance of small-scale owners to join associations. Their lack of motivation is caused by insufficient funding from the government supporting the administration and management of associations. The reluctance also results from the request for associations to be legal entities, which most applicants do not meet as they are either not registered or are registered under unsuitable legal forms. Between 2011 and 2013, no contributions were paid by the government to associations, and no new small-scale forest owners’ associations were formed. To increase associations, we propose that the government should provide sufficient funding not only for the administration and management of associations but also for the process of establishing associations and initial investments. It is also necessary to make major innovations in legislature regarding the transition of ownerships to more convenient legal forms. 相似文献
40.
Miren del Río Hans Pretzsch Iciar Alberdi Kamil Bielak Felipe Bravo Andreas Brunner Sonia Condés Mark J. Ducey Teresa Fonseca Nikolas von Lüpke Maciej Pach Sanja Peric Thomas Perot Zahera Souidi Peter Spathelf Hubert Sterba Martina Tijardovic Margarida Tomé Patrick Vallet Andrés Bravo-Oviedo 《European Journal of Forest Research》2016,135(1):23-49