印楝引种试验初报

1986年在我国海南省万宁县首次引种印楝(Azadirachta indica A.Juss)的初步结果表明,印楝树适宜在该地种植,在没有采取特殊保护措施的自然条件下能顺利越冬越夏,生长情况良好。育苗三个月即可移植出圃造林。移植两年后可郁闭成林。平均株高可达6米,胸径达9.8厘米。树龄两年即出蕾开花,首次花期在4～5月份。同年8～9月份果实成熟,产生的种子具有正常生活力。据试验期间观察,印楝还具有较强的抗风和耐旱能力,并具有一定的抗寒能力,是值得进行大量推广的速生树种。     

Both anti-oxidation and lipid-carbohydrate conversion enhancements are involved in priming-improved emergence of Echinacea purpurea seeds that differ in size

This study evaluated the effects of priming on emergence responses of purple coneflower (Echinacea purpurea L. Moench) seeds. The seeds that differ in seed size were either primed with moistened vermiculite (solid matrix priming) or primed in non-aerated −0.5 MPa polyethylene glycol 6000 solution at 25 °C for 6 days (osmopriming), followed by air-drying to their initial moisture level. The tetrazolium staining tests indicated that both large and small seeds were biochemically viable. No notable difference in germination percentage was found between large and small seeds. However, extensive cavity was visible in portions of small seeds in comparison with large seeds. Large seeds accumulated more antioxidants and had greater activities of anti-oxidative enzymes than small seeds. They also had greater isocitrate lyase and malate synthase activities than small seeds. As a result, large seeds had higher emergence percentage and faster emergence speed as compared to that of small seeds. Both solid matrix priming and osmopriming increased emergence percentage and shortened mean emergence time of purple coneflower seeds by increasing the activities of anti-oxidative enzymes and decreasing the levels of malondialdehyde and total peroxide accumulation. Moreover, priming also enhanced the anti-oxidative activities of treated seeds. The activities of isocitrate lyase and malate synthase were also increased in primed seeds. The enhanced anti-oxidation and lipid-carbohydrate conversion activities might explain in part why primed purple coneflower seeds emerged better than non-primed seeds.     

Echocardiographic evaluation of the effects of medetomidine and xylazine in dogs

The echocardiographic effects of medetomidine and xylazine were evaluated in 6 healthy dogs. Values for echocardiographic variables were significantly different from pre-treatment values after administration of both drugs. The effects of medetomidine were similar to that of xylazine. Because of their cardiac depressant effects, both drugs should be used with care in sick dogs.     

NS-83对桃蚜传播芜菁花叶病毒(TuMV)的作用

 1% NS-83乳剂喷布饲毒毒源芥菜(Brassica juncea)病株与检测植物油青菜(Brassica chinensis)植株,桃蚜传播TuMV受到了显著抑制,抑制效果为39.0%左右,但用乳化剂处理的植株未表现抑制作用。NS-83的抑制效果随使用乳剂中NS-83浓度升高而增加,随接种压力(每株传毒蚜虫数)增大而降低。桃蚜在传毒前、饲毒时和传毒时口针接触NS-83后,传播TuMV分别受到了41.8,29.4和14.1%的抑制。NS-83以不同方式处理饲毒株与传毒株,抑制效果不同,结果表明NS-83在TuMV一桃蚜复合关系中起作用。用1% NS-83乳剂涂抹芥菜叶片6、12、24、48小时后,桃蚜在上面的探食(试探取食)行为发生了显著的改变,表现在所观察的探食时间的缩短及两次探食间爬行时间的延长。     

Serological survey for antibodies to Encephalitozoon cuniculi in rabbits in Taiwan

Encephalitozoon cuniculi (E. cuniculi) is a microsporidian parasite commonly found in rabbits that can infect humans, causing encephalitozoonosis. Our laboratory recently confirmed the first case of encephalitozoonosis in a rabbit in Taiwan; the prevalence of encephalitozoonosis is not well documented, even when many clinics suspect pet rabbits as being infected. This study surveys the seropositivity of E. cuniculi using carbon immunoassay (CIA) and enzyme-linked immunosorbent assay (ELISA). Serological examination of 171 rabbits using CIA and ELISA showed that 63.2% (108/171) and 67.8% (116/171) were seropositive against E. cuniculi, respectively. Thirteen of the 14 rabbits (92.9%) with neurological symptoms were seropositive. Except for gender, health status and location had a significant effect on E. cuniculi seropositivity (p<0.05). Adult rabbits aged older than 4 months exhibited significantly higher seropositivity for E. cuniculi than young rabbits (p<0.05). In conclusion, this study shows that E. cuniculi is present and widespread among healthy rabbits in Taiwan. Therefore, the fields of veterinary and human medicine in Taiwan should be aware of this zoonotic issue and the resulting public health concern of encephalitozoonosis.     

Auricular chondropathy in aging rats

An external ear lesion designated as auricular chondropathy in aging Crl:CD rats was reported. One hundred eighty (180) of 4,876 rats (3.7%) had ear deformity. Grossly, the ears were thickened, nodular, or disfigured. Both ears were affected in most rats. The lesions primarily involved the cartilaginous plate and were associated with two processes--chondrolysis and granulomatous inflammation. The detailed morphogenesis of the lesions is described, but the etiology of the lesions is unknown. Auricular chondropathy in rats and relapsing polychondritis in man are compared.     

Major pol gene progenitors in the evolution of oncoviruses

The genetic relationships among molecularly cloned prototype viruses representing all of the major oncovirus genera were investigated by molecular hybridization and nucleotide sequence analysis. One of the major progenitors of the pol genes of such viruses gives rise to mammalian type C viruses and another gives rise to type A, B, D, and avian type C oncoviruses. Evidence of unusual patterns of homology among the env genes of mammalian type C and D oncoviruses illustrates that genetic interactions between their progenitors contributed to the evolution of oncoviruses.     

硅钙复混肥对玉米抗倒性及产量的影响

据报道 ,水稻施用硅肥后 ,能提高植株体内ＳｉＯ2 含量 ,提高细胞壁的强度 ,进而株形挺拔、抗倒伏。小麦试验亦表明 ,施硅增加冬小麦表皮细胞壁厚度和硅化细胞数量 ,提高茎秆刚性。但到目前为止 ,关于施硅钙肥对玉米抗倒性能及产量影响的报导甚少。为此 ,我们探讨了在正常密度条件下 ,施用硅钙复混肥对玉米抗倒伏及其产量的影响 ,为科学施用硅钙肥提供理论依据。1　材料与方法本项目于 1 996年布置在辽宁省农业科学院土肥所试验地上 ,土壤为壤质草甸土 ,其理化性质为有机质 2 8.45ｇ/ｋｇ ,全氮 0 .0 93%,全磷 0 .8ｇ/ｋｇ ,全钾 2 8.1 5ｇ/…