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51.
Whitaker BD Schmidt WF Kirk MC Barnes S 《Journal of agricultural and food chemistry》2001,49(8):3787-3792
Hexane extracts of epicuticular wax from cv. Gala apples were noted to have an unusual, broad absorbance maximum at approximately 258 nm, which led us to isolate and identify the primary UV-absorbing compounds. Column and thin-layer chromatography yielded a fraction that gave a series of paired, 260-nm-absorbing peaks on C(18) HPLC. These were shown to be a family of phenolic fatty acid esters, for which retention times increased with increasing fatty acid chain length, and paired peaks were esters of two related phenolics with the same fatty acid moiety. Alkaline hydrolysis of the esters released two water-soluble phenolics separable by C(18) HPLC. Electrospray ionization mass spectrometry gave a molecular mass of 150 for both, and (1)H NMR plus UV absorbance spectra identified them as E and Z isomers of p-coumaryl alcohol. Alkaline cleavage of the fatty acid esters in the presence of methanol or ethanol resulted in partial derivatization of E-p-coumaryl alcohol to the corresponding gamma-O-methyl or O-ethyl ether. Gradient HMQC NMR of the HPLC-purified stearate ester of E-p-coumaryl alcohol indicated that fatty acid esterification occurs at the gamma-OH rather than at the 4-OH on the phenyl ring. This is the first report of fatty acid esters of monolignols as a natural plant product. 相似文献
52.
P. A. Flecknell A. J. B. Kirk C. E. Fox J. H. Dark 《Veterinary anaesthesia and analgesia》1990,17(1):11-16
Prolonged surgical anaesthesia in the dog was induced with propofol (6.5 ± 1.3 mg/kg) followed by alfentanil (25.5 ± 5 μg/kg) (mean ± 1 sd) and maintained with a continuous infusion of propofol (0.14 to 0.18 mg/kg/min) and alfentanil (2 to 3 μg/kg/min). Neuromuscular blockade was produced with vecuronium (0.1 mg/kg). After induction of anaesthesia with propofol, administration of alfentanil to dogs which had received no pre-anaesthetic medication produced cardiac arrest and apnoea. Administration of atropine intravenously immediately prior to alfentanil prevented these cardiac depressant effects. The cardiac depressant effect of alfentanil was not as severe in a second group of dogs in which anaesthesia was induced with thiopentone. After commencing the continuous infusion anaesthetic regime and establishment of IPPV, blood pressure and heart rate remained stable during the remaining 4 to 6 h period of anaesthesia. Recovery from anaesthesia was smooth and uneventful. The depressant effects of alfentanil on respiration and on consciousness were reversed rapidly by administration of nalbuphine (10 mg total dose). The smooth recovery and the integration of anaesthesia and post operative analgesia attained by the reversal of alfentanil with nalbuphine make this an attractive anaesthetic regime for major surgery in dogs, provided that facilities for IPPV are available. 相似文献
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Kristian Overskaug 《Acta veterinaria Scandinavica》1994,35(4):457
Sarcoptic mange (Sarcoptes scabiei var. vulpes) reached Scandinavia in the mid-1970’s and is mainly prevalent among red foxes (Vulpes vulpes) (Borg 1987). In the laboratory, foxes succumb 2–4 months after being infested, and it is commonly thought that carriers in the wild exhibit an abnormal behaviour and quickly die (Mörner & Christensson 1984, Holt & Berg 1990). However, there is a lack of comparative data from free-ranging animals to contribute to the ecology of the species in general and ta supplement the content of the above selected references in particular (e.g. Plowright 1988). Using telemetry studies, I have compared the behaviour in winter of 2 mange infested and 2 healthy red foxes. The work took place in 1987 and 1990 in a boreal area adjacent to farmland in central Norway (63° 20′N 10° 45′E). 相似文献
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The area of skin supplied by afferent fibers in a peripheral nerve is called the cutaneous area (CA) of that nerve. The CA of hind limb nerves that were responsive to movement of wool/hairs were mapped neurophysiologically in 25 barbiturate-anesthetized sheep. The CA of the dorsal cutaneous branches of the caudal lumbar spinal nerves and of the sacral spinal nerves extended over the lateral aspect of the thigh. The CA of the lateral cutaneous femoral nerve was restricted to the stifle region, that of the saphenous nerve did not reach the digits, that of the deep peroneal nerve lay between the 3rd and 4th digits, and that of the lateral plantar nerve was confined to the lateral aspect of the 4th digit. The CA of the superficial peroneal nerve enveloped the dorsal, medial, and lateral aspects of the distal portions of the hind limb. In some sheep, the boundaries of the CA of the superficial peroneal nerve were juxtaposed caudally in such way that the medial plantar nerve did not have an autonomous zone. Differences in sizes of the CA resulted in corresponding differences in the overlap between adjacent CA and concomitant differences in the sizes of autonomous zones. 相似文献
58.
Endometriosis in four irradiated rhesus monkeys 总被引:3,自引:0,他引:3
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Phillips DJ Jones KL Clarke IJ Scheerlinck JP de Kretser DM 《Veterinary immunology and immunopathology》2005,108(1-2):23-27
The growth factor, activin A, was initially characterized as a putative reproductive hormone but is now known to have many other divergent roles. One of these is during inflammation. Following intravenous injection of bacterial lipopolysaccharide (LPS) into sheep, activin A is released extremely rapidly into the circulation. The release of activin A appears to be independent of fever, prostaglandins or other key proinflammatory cytokines such as TNF-alpha or IL-1beta. While the precise roles and function of this factor in inflammation are yet to be elucidated, the activin response occurs in other mammalian species besides the sheep and elevated activin has been documented for a number of clinical inflammatory conditions. Activin A therefore seems to be part of the regulatory component of the innate immune response. 相似文献