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SUMMARY: Case records of 450 horses with signs of neurological disease are reviewed. One hundred and nineteen horses with neurological disease due to trauma were examined, of which 60 were due to spinal cord trauma, 47 to brain or cranial nerve trauma and 12 to peripheral nerve trauma. Cervical vertebral fractures/trauma were the most common injury. Basisphenold/basloccipital bone fractures were the most common form of cranial trauma and facial nerve paralysis the most common cranial nerve injury. Eighty-nine horses with neurological disease due to malformation were examined. Cervical vertebral malformation occurred in 83 horses and congenital defects in 6 foals. Neurological disease due to inflammation or infection occurred in 30 horses. The most common disease of this type was meningitis, which occurred in 11 horses and foals. Neoplasms in the CNS caused neurological disease in 8 horses. The final category was miscellaneous neurological disease, which was diagnosed in 204 horses. Diseases in this category included neonatal (28 cases), toxic/metabolic (27 cases), idiopathic (133 cases), degenerative (3 cases) and other neurological diseases (13 cases). The most common condition was idiopathic laryngeal hemiplegia (116 cases).
Where possible, diagnosis relied on a thorough neurological examination with use of ancillary tests in selected cases including rhinolaryngoscopy, radiography, myelography, ophthalmoscopy and cerebrospinal fluid analysis when indicated. In many cases necropsy and histopathological confirmation or diagnosis was necessary.  相似文献   
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Diversity and weed community composition of mid-season plant stands and autumn seedbanks were examined in spring barley–red clover cropping systems that varied according to crop rotation, tillage and weed management. Weed plant and seed density data collected over 4 years were used in the calculation of species richness (number of species), evenness (Shannon's E) and diversity (Shannon's H′), and in multivariate analysis (canonical discriminant analysis) of weed communities. Weed diversity indices were low (H′ < 2.0) but sensitive to management practices. Evenness had intermediate values (E = 0.4–0.8), suggesting little evidence of truly dominant species, particularly in the seedbanks. The difference in the number of species between treatments was never large (approximately two to four species). Overall, diversity indices were highest in the low disturbance treatments, particularly those with minimum weed management. Factors affecting ordination were somewhat different from those affecting diversity. Tillage had little effect on weed diversity indices but had a more major role in determining weed community composition. Seedbanks in no-till and monoculture-chisel plough treatments appeared to have more distinctive species composition compared with other treatments. Weed species assembly in seedbanks showed little discrimination across treatments and over time, confirming the ability of seedbanks to buffer disturbances across a variety of cropping systems. The use of diversity indices revealed part of the complexity of weed communities associated with disturbance in cropping systems, whereas ordination singled out species–cropping systems associations, which may be more meaningful to weed management.  相似文献   
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以番茄为试材,采用膜下滴灌方式,对比不同腐植酸复混肥的施用量和配比对番茄的产量与品质指标及经济效益的影响,以确定适合新疆地区加工番茄施腐植酸肥施用的适宜用量和方法。结果表明:增施腐植酸复混肥均能提高加工番茄的单株结铃数、单果质量和产量;腐植酸复混肥对加工番茄的可溶性固形物、番茄红素、硝酸盐、亚硝酸盐、总酸、总糖和维生素C含量及pH影响显著。硫酸钾和氯化钾在番茄品质上的作用有差异,硫酸钾主要增加了番茄红素、硝酸盐、总酸含量,氯化钾主要增加了pH、可溶性固形物、总糖、维生素C含量,其中硫酸钾适宜配在基肥中,氯化钾适宜配在追肥中。综合性价比,适宜推荐加工番茄腐植酸复混肥基肥配方为N-P-K配比9-17-12,腐植酸为17.5kg,微量元素为0.5kg,有机质为12.5kg,膨润土为7.5kg。复混肥追肥配方N为115g·L~(-1),K为50g·L~(-1),腐植酸为161g·L~(-1),微量元素为0.3 g·L~(-1),每7 d追肥一次,追肥2 100L·hm~(-2),增产幅度达到10.73%。  相似文献   
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巴旦杏砧木组织培养及植株再生   总被引:7,自引:2,他引:5  
以新疆南疆咯什、和田地区的巴旦杏砧木品种桃巴旦、石头巴旦树上当年结的种子为试材,先用赤霉素打破休眠,消毒后接种子诱导生长及分化的培养基上。生长约一个月后,将由试管中种子培养长成的小植株剪切成长约1cm的单芽茎段,接入增殖培养基,20d后将增殖伸长的嫩茎用于生根,再将生根后的巴旦杏苗移栽到珍珠岩基质中培养,进行有效的移栽驯化管理,获得了较理想的移栽成活率。成功地进行了离体组织培养及植株再生。  相似文献   
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