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排序方式: 共有359条查询结果,搜索用时 46 毫秒
71.
72.
F.J. Zhao S. Fortune V.L. Barbosa S.P. McGrath R. Stobart P.E. Bilsborrow E.J. Booth A. Brown P. Robson 《Journal of Cereal Science》2006,43(3):369-377
Eight field experiments were conducted at four sites in the UK in 2003 and 2004 to investigate the effects of sulphur (S) application on yield and malting quality of barley. Significant yield responses to S additions were obtained in five out of the eight experiments, with yield increases ranging from 0.2 to 1.2 t/ha (4.7–22.5%). At the two most S-deficient sites, S application significantly increased malt diastatic power, alpha-amylase activity, friability and homogeneity, and decreased (1→3,1→4)-β-glucan concentration in the wort, indicating an improved endosperm modification during malting. Sulphur applications also significantly increased the concentration of S-methylmethionine (the precursor of dimethylsulphide) in kilned malt, which could impact on beer flavour. When the supply of N was limiting, S applications decreased grain N concentration due to a dilution effect as a result of increased grain yield. In some cases, S applications resulted in decreased grain size. At sites non-deficient or marginally deficient in S, applications of S had little effect on grain or malting quality parameters. The need to maintain an adequate S supply to barley for both yield and malting quality was demonstrated. 相似文献
73.
Josephine E. Booth Kevin J. Gaston Karl L. Evans Paul R. Armsworth 《Biological conservation》2011,144(11):2728-2732
Wildlife viewing recreation offers conservationists opportunities for education and generating revenue but can also have detrimental ecological impacts. To manage these opportunities and impacts effectively, a better understanding is needed of what people value in wildlife viewing events. We examine the relationship between species rarity and value for wildlife viewing recreation. We undertook visitor counts of birdwatchers attending rare (vagrant) bird sightings and collected home postcodes to assess the distances these individuals travelled to achieve these sightings. We also undertook visitor counts at common bird viewing locations for comparison. We regressed birdwatcher numbers against rarity, site protection status, time the bird had been on site and day of the week when the count took place. We undertook these analyses for rare bird sightings only, using a continuous measure of rarity, and for both rare and common species combined, using a categorical rarity index. Species rarity was the clearest predictor of visitor numbers in both the analyses. When studying rare birds only, we found the functional form of the relationship between rarity and visitor numbers to be inverse and asymptotic. Individuals also travelled further to see rarer species. However, while exceptional numbers of visitors attended exceptionally rare bird sightings, the marginal value of rarity appeared to be relatively low. Despite the opportunity for revenue raising and education provided by rare bird sightings, a comparison of visitor numbers at sightings inside and outside protected areas showed no evidence that managers of protected areas capitalise on these opportunities. 相似文献
74.
A 15-month-old, male neutered Staffordshire Bull Terrier cross was presented to its referring veterinarian collapsed and agonal. He was immediately intubated, manually ventilated, and treatment commenced for presumptive snake envenomation with two vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial). The dog was transferred to a referral hospital intubated. Additional diagnostics performed following arrival at the referral hospital included a urine snake venom detection kit test, which was positive for brown snake immunotype. Three additional vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial) were administered until the dog was extubated and able to stand. Venom-induced consumptive coagulopathy (VICC) was diagnosed based on prolonged clotting times and scleral haemorrhage. Paroxysms of right ventricular outflow tract (RVOT) origin ventricular arrhythmias were treated with lignocaine and sotalol. Four days after presentation, a new-grade IV/VI systolic heart murmur was auscultated, prompting an echocardiogram. An anechoic and compartmentalised mass measuring 43 mm × 19 mm was visualized within the right ventricular wall at the RVOT, immediately adjacent to the pulmonic valve. The mass was causing a RVOT obstruction. Its appearance was suggestive of an intramyocardial haematoma, most likely secondary to VICC. The dog remained cardiovascularly stable, and treatment consisted of supportive care. Recheck echocardiograms at 2 and 7 weeks after discharge revealed progressive improvement of the intramyocardial mass and resolution of the associated heart murmur. Although intramyocardial haematomas are rare, it should be considered as a differential in dogs that develop a newly diagnosed heart murmur and/or cardiac arrhythmia following brown snake envenomation. 相似文献
75.
Bruce L. Parker Robert H. Booth James E. Bryan 《American Journal of Potato Research》1983,60(2):65-74
Population levels ofMyzus persicae (Sulzer) were studied on potato tubers in diffuse light and dark rustic storage houses in Peru. No differences in numbers of aphids/sprouted eye on potatoes infested naturally during storage in diffuse light or darkness were observed. Significantly more alate aphids were observed on tubers stored in darkness than in diffuse light storage houses. Viral transmission was occurring during the storage period. The incidence of viral transmission was not significantly influenced by storing tubers in diffuse light or dark storages. There were significantly more plants infected with virus from tubers that had not been sprayed for aphid control than from tubers that had been sprayed 相似文献
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CJ Pearce 《New Zealand veterinary journal》2020,68(3):178-186
ABSTRACTEquine dentistry is a rapidly developing clinical specialty. It has benefitted from key advances in anatomical and physiological research, development of equipment and instrumentation, utilisation of standing sedation and anaesthesia protocols, a change towards minimally invasive surgical techniques, and the introduction of restorative and endodontic techniques translated from techniques used in human and canine dentistry. Anatomical research has provided further insight into the endodontic system of incisors and cheek teeth and how it changes throughout development with age. Studies of the periodontium have demonstrated a rich vascular supply and repair capacity. Routine dental visits are increasingly being performed utilising sedation and clinical instruments for routine examinations. Equipment has become more efficient, battery-operated and miniaturised giving benefits to both equine dental maintenance work and advanced techniques, assisting the transition to minimally invasive techniques, and the development of endodontic and restorative dentistry. Diagnosis has also benefitted from advances in equipment such as patient-side digital radiography systems, high definition oroscopy, and small diameter flexible fibrescopes that are capable of visualising inside a pulp canal. Dental units combining endodontic high- and low-speed drills, suction and air or water flush are becoming increasingly used and adapted for equine use. Sedative combinations and standing anaesthesia protocols have meant that revisions of traditional techniques, as well as novel techniques, can be performed with almost no requirement for general anaesthesia. Equine dentistry can only continue to advance in this way if there is early identification of dental disease through clinical oral examinations, leading to a system based on prophylaxis, as in human dentistry. This necessitates a change in attitude of the public and industry in general to a proactive approach, with early intervention based on examination and diagnostic findings of practitioners and not necessarily based on the clinical signs displayed by the patient. 相似文献
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80.
S. KAMOLSIRIPRICHAIPORN PT HOOPER CJ MORRISSY HA WESTBURY 《Australian veterinary journal》1992,69(10):240-244
The virulence of a strain of hog cholera virus isolated during an outbreak of mild disease in pigs in New South Wales in 1960/61 (the NSW strain) was compared over 11 days with that of a virulent strain by inoculating 8 pigs with each virus and comparing the ensuing clinical signs and pathology. Both viruses caused persistent pyrexia and leukopenia, the NSW strain 4 to 5 days and the virulent strain 3 days, after inoculation. Few other clinical signs were observed in the pigs inoculated with the NSW strain. In contrast, all pigs inoculated with the virulent strain became progressively depressed and incoordinated, and were killed between days 6 and 9. Bronchopneumonia and swollen, reddened lymph nodes were observed in pigs inoculated with both viruses. Few other gross lesions were observed with the NSW strain, but some pigs receiving the virulent strain had pustules in the tonsil and the anterior oesophagus, petechial haemorrhages in the kidney, and small infarcts at the margins of the spleen. There were marked differences in the histopathology, both in the variety of organs affected and the severity of lesions in individual organs. Suppurative bronchopneumonia occurred in both groups. Other changes in the pigs affected with the NSW strain were colitis, mild cerebral vasculitis, necrosis, haemorrhage and neutrophil infiltration in some lymph nodes and spleens. In pigs infected with virulent virus the cerebral vasculitis was so severe that there was necrosis of cells within the vessel walls.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献