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171.
172.
超高压对草鱼肌肉超微结构与质构特性的影响 总被引:3,自引:0,他引:3
研究了等静超高压对草鱼肌肉超微结构与质构特性的影响,并与猪肌肉用对照。结果表明:1.加压处理的草鱼肌肉,其超微结构中出现较明显的变化,如肌原纤维中A带和I带的细丝均被破坏,粗丝相互聚集,出现间隙,Z线变粗,不连续,H带和M线消失等,但肌原纤维的外形仍保持完整。2加压处理的草鱼肌肉,其外观无显著变化,色泽稍白,略有汁液流出,但质构特性与处理前无明显差别。 相似文献
173.
A 4‐year‐old, spayed female greyhound dog was presented with an acute onset of paraplegia. There was no known history of trauma or coagulopathy. Spinal cord compression was identified on MRI. Intra‐operative evaluation revealed the presence of a large subperiosteal hematoma and a smaller epidural hematoma. To the authors’ knowledge, this is the first report of a spinal subperiosteal hematoma diagnosed antemortem through MRI, with surgical exploration and successful treatment in a dog. 相似文献
174.
175.
应用RFV评价鄂尔多斯荒漠草原优势牧草营养价值 总被引:1,自引:0,他引:1
将采自内蒙古鄂尔多斯地区的禾本科牧草3种、豆科牧草3种和菊科牧草3种分别于6月、7月和9月刈割晾干,共制得27个样本。通过应用饲料相对指数(RFV)进行综合评定可知:将6月、7月和9月分别刈割的同一品种牧草混合后,品质最好的为中苜2号,其次是沙打旺,再次是沙蒿,最差的是花棒;同种牧草不同刈割期比较可知:对于禾本科牧草来说,针茅、冰草和中苜2号在不同刈割期营养价值的大小顺序为6月7月9月;对于豆科牧草来说,花棒、沙打旺在不同刈割期营养价值的大小顺序为6月7月9月,但草木樨在不同刈割期营养价值的大小顺序则为6月9月7月;对于菊科牧草来说,沙蒿、猪毛蒿、籽蒿在不同刈割期营养价值的大小顺序为7月6月9月。 相似文献
176.
177.
The growth of two breeds of common carp, Cyprinus carpio L., was tested in ponds under the climatic conditions of South Bohemia. T?eboň scaly carp (TR) and Hungarian mirror carp (M2) were kept in both low and high stocking densities during the second growing season and then stocked together for communal testing during the third growing season. Before the communal testing, the mean initial weights of fish from low‐ and high‐density stocks differed significantly (374.1 vs. 227.7 g for the TR breed and 766.7 vs. 317.3 g for the M2 breed respectively, P<0.01). After communal testing, mean weights of fish from low‐ and high‐density stocks gained 761.8 vs. 543.8 g for the TR breed and 1339.7 vs. 706.7 g for the M2 breed respectively. These observed weights were also significantly different (P<0.01). However, the test of corrected weight gain, i.e. gain not related to the initial weight of fish, revealed insignificant differences (P>0.01) between the weight gains after correction, i.e. the effect of different initial weights was successfully eliminated. These results seem to confirm the applicability of this method for the assessment of growth of purebred common carp under the climatic conditions of Central European fish farms. 相似文献
178.
The stress response of grass carp to salinity was evaluated assessing the levels of hematocrit, leucocrit, plasma glucose, sodium, potassium and calcium. Mean hematocrit values increased following exposure to salinity. Mean leucocrit values elevated after exposure to salinity for 24 h, then decreased. Mean plasma glucose increased during saline exposure for 48 h and then decreased to normal values. Plasma sodium and chloride levels were increased to their highest values after 48 h. While plasma potassium value increased with the exposure time, plasma calcium values were not affected by salinity exposure. 相似文献
179.
The temporal dynamics of appetite (weight of food consumed per day) were analysed for fish fed to satiation after a 1 or 2-week period of feed deprivation. Three species were compared: two omnivores (minnow, Phoxinus phoxinus and gibel carp, Carassius auratus gibelio) and a carnivore (three-spined stickleback, Gasterosteus aculeatus). All species showed compensatory changes in appetite and growth during the re-feeding period but in the stickleback, there was a lag of a week before the compensatory response was detected. The temporal dynamics of appetite differed between the three species but not within a species. Appetite of the minnow declined towards control levels from the onset of re-feeding. In gibel carp, appetite increased to a peak and then declined to control levels. In the stickleback, appetite was initially below control levels, increased to a maximum, then declined towards control levels. The differences between the species might have been artefacts of the experimental protocols used but could also reflect underlying differences in the control of appetite in these species of fish. 相似文献
180.
A procedure is described for the isolation of intact vitellogenin (c-VTG) from the carp, Cyprinus carpio. VTG was induced in juvenile females using oestradiol-17β and purified from the plasma using a combination of gel-filtration
chromatography on Sepharose 6B and ion exchange chromatography on DEAE-cellulose. Purification procedures were conducted at
low temperatures (below 9°C) in the presence of the proteolytic enzyme inhibitor aprotinin to prevent degradation. Intact
c-VTG had an apparent molecular mass of 390,000 Daltons, but when extracted from plasma in the absence of aprotinin it underwent
proteolysis into at least 2 protein fragments (apparent molecular masses of 230,000 and 96,000 Daltons), showing an instability
of the native dimer. An amino acid analysis of c-VTG showed that its composition was almost identical to goldfish VTG, a species
closely allied to the true carps and also similar to other oviparous vertebrate VTGs. Collectively, these data indicate that
using these purification procedures VTG from carp, and probably other teleost species, can be isolated in an intact, highly
purified form. 相似文献