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101.
对杭州地区郁金香退化原因的研究 总被引:3,自引:0,他引:3
研究证实了郁金香在杭州地区栽培出现普遍退化现象的原因不是气候问题,而是栽培技术问题,我们以荷兰郁金香商品球的重量、花瓣大小和繁殖系数为检验退化的标准,连续四年栽培试验,所得第四代更新球与引进的商品球相比,重量由原来的25.10 g增加到35.927 g,花瓣大小与商品球花瓣火小一致,繁殖系数与荷兰同品种的记载一致,更新球的合格率与开花率均达100%。由此证明,郁金香在杭州地区完全可以正常地完成其生活史并繁衍健康的后代,为进一步大面积生产性栽培提供了理论依据。最后,作者还提出了在杭州地区正确栽培郁金香的技术要点, 相似文献
102.
Kristin Hamre Brit Hjeltnes Harald Kryvi Sverre Sandberg Mette Lorentzen Øyvind Lie 《Fish physiology and biochemistry》1994,12(5):421-429
Atlantic salmon (Salmo salar) fry, initial weight 0.16 g, were fed a semipurified diet with 0, 15, 30, 60 or 120 mg dl-α-tocopheryl acetate/kg. After
24 weeks, the first two of these groups were extinct, and the fish receiving 30 mg/kg were clearly vitamin E deficient. Vitamin
E deficient fish had low hemoglobin levels, characterized by a combination of reduced cellular hemoglobin concentration, red
cell volume and red cell number, and an increased number and fraction of immature red blood cells. The hemoglobin concentration
decreased over the decreasing range of experimental dl-ga-tocopheryl acetate levels. Therefore, even if 60 mg dl-α-tocopheryl
acetate/kg gave good survival, this level was clearly physiologically suboptimal. Ceroid accumulated in the liver of fish
fed 30 mg vitamin E/kg, and autofluorescent inclusions were found in the red blood cells of fish fed 30 and 60 mg vitamin
E/kg. Degeneration of skeletal muscle was not observed in the present study. 相似文献
103.
104.
本文研究了高变性芝麻饼粕中含硒量、生物效能、溶解性、分布及存在形式等特性,并采用 D 型大柱凝胶电泳分析其可溶性蛋白硒络合分子量范围为21KD-30KD。 相似文献
105.
The heritability of calcified intervertebral discs in the dachshund was estimated using data gathered from a radiographic study. Radiographs of the vertebral columns of 274 clinically normal, 12 to 18 months old dachshunds, were examined. The dogs were offspring from 75 different sires, representing the same number of half sib groups. There were 2 to 14 offspring in each half-sib group. The number of full sib groups was 81.Calcified intervertebral discs were identified in 20.4 % of the dogs. An analysis of variance that used the data as a continuous and as an either/or-variable estimated the heritability of calcified discs to be 0.22 and 0.15 respectively.A genetic factor was found to be essential for the occurrence of calcified discs in a dog while a common environmental factor presumably resulting from non-genetic causes was significant in determining the number of discs to undergo calcification in affected dogs. 相似文献
106.
Christopher L. Mariani DVM Roger M. Clemmons DVM PhD John P. Graham MVB MSc Lynette A. Phillips DVM PhD Cheryl L. Chrisman DVM MS EDS 《Veterinary radiology & ultrasound》2001,42(4):285-290
A 7-month-old, neutered female Labrador Retriever was evaluated for tetraparesis and subtle cerebellar dysfunction. Clinical signs progressed over a period of 6 weeks to severe ataxia, hypermetria, intention tremors, and finally non-ambulatory tetraparesis. On magnetic resonance imaging of the brain there were large, bilaterally symmetrical, ovoid lesions in the region of the deep cerebellar nuclei that were hyperintense on T2-weighted and proton density images and hypointense on T1-weighted images. There were similar but smaller bilaterally symmetrical lesions present within the thalamus. Euthanasia was performed and lesions consistent with the previously described spongy degeneration of Labrador Retrievers were identified. This disease and its relation to similar human heritable leukodystrophies are discussed. 相似文献
107.
The occurrence of asymptomatic disappearance of intervertebral disc calcification was evaluated in a radiographic prospective longitudinal study of 40 Dachshunds followed from 6 or 12 months of age to 2 years of age. Radiographic follow-up was performed at 3 to 4 years of age in 12 dogs. Disappearance of calcified disc material was observed in 9 thoracic and 1 lumbar intervertebral discs. The crude incidence rate tended to increase with age from 1 year of age. The features of the disappearing calcifications involved indicate that the phenomenon is part of the progressive degenerative process. A possible pathogenesis includes tearing of the annulus fibrosus due to the severe degeneration of the disc, followed by an inflammatory response to nuclear material and phagocytic resorption of calcified material. 相似文献
108.
OBJECTIVE: To describe the clinical findings and the age of onset of cone-rod dystrophy (crd) in the Standard Wire-haired Dachshund (SWHD) and to evaluate which clinical tests could be used to obtain a reliable diagnosis. ANIMALS: Sixty-eight SWHD and SWHD-derived dogs were used, including 23 affected with crd and 45 controls, respectively. PROCEDURES: The dogs were subjected to behavioral testing, examination of pupillary light reflexes (PLRs), indirect ophthalmoscopy and bilateral full field electroretinography (ERG). RESULTS: The majority of affected puppies (5-10 weeks) displayed pin-point sized pupils upon examination with focal light. All dogs in the control group, except one, displayed normal PLRs upon examination. In all crd-affected dogs there was a great variation both in age of onset and in clinical appearance of retinal changes upon fundoscopy. Two siblings displayed panretinal degeneration at the age of 10 months while other affected dogs showed early changes at the age of 3 years. Generalized bilateral retinal atrophy was the end stage of the disease. The maze test revealed no obvious differences among affected and unaffected groups. ERG recordings showed only slightly reduced rod, and mixed rod-cone responses, but severely reduced cone single flash a- and b-wave amplitudes, and cone flicker amplitudes were observed in all affected dogs. CONCLUSION: Presence of pin-point sized pupils in young SWHDs was found to be an important indicator of early onset crd. Fundoscopic changes and progression of disease at later stages resembled those previously described in the majority of progressive retinal atrophies in dog. ERG was found to be the most reliable diagnostic procedure to clinically diagnose crd in the SWHD. 相似文献
109.
Shiori CHIBA Shingo FUNATO Noriyuki HORIUCHI Kotaro MATSUMOTO Hisashi INOKUMA Hidefumi FURUOKA Yoshiyasu KOBAYASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):147-154
Degeneration of the optic pathway has been reported in various animal species including cattle. We experienced a case of bilateral optic tract degeneration characterized by severe gliosis in a Japanese black cattle without any obvious visual defects. To evaluate the significance, pathological nature and pathogenesis of the lesions, we examined the optic pathway in 60 cattle (41 Japanese black, 13 Holstein and 6 crossbreed) with or without ocular abnormalities. None of these animals had optic canal stenosis. Degenerative changes with severe gliosis in the optic pathway, which includes the optic nerve, optic chiasm and optic tract, were only observed in 8 Japanese black cattle with or without ocular abnormalities. Furthermore, strong immunoreactivity of glial fibrillary acidic protein was observed in the retinal stratum opticum and ganglion cell layer in all 5 cattle in which the optic pathway lesions could be examined. As etiological research, we also examined whether the
concentrations of vitamin A and vitamin B12 or bovine viral diarrhea virus (BVDV) infection was associated with optic pathway degeneration. However, our results suggested that the observed optic pathway degeneration was probably not caused by these factors. These facts indicate the presence of optic pathway degeneration characterized by severe gliosis that has never been reported in cattle without bilateral compressive lesions in the optic pathway or bilateral severe retinal atrophy. 相似文献
110.