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991.
992.
本刊2006年第23期刊登了《养宠物犬是时尚还是公害》一文后．读者非常关注。他们认为加强宠物犬管理刻不容缓．尤其是在人口密度高度集中的城市．因为宠物犬伤人事件和部分地方逐渐回潮的狂犬病危害事件日益增多。那么犬患横行．城市养犬究竟该如何管理？记者再次进行了追踪报道．[编者按] 相似文献
993.
994.
生活和工作在纷争不断、暴力血腥的以巴地区,有时感觉感受“事件”,更多超过感受城市本身。当今天坐下来,静静整理记录下来文字片段,发现以色列在我的记忆中留下了一些关于城市的深刻印记。 相似文献
995.
996.
晓阳 《农业机械化与电气化》2002,(5)
若是自己驾车碰了行人,被害人如被弹上汽车前面的罩子上,应随即停车,使其不致坠落地上。根据实验,任何人一经自汽车前面罩子上坠下,必定是自头部坠下,其冲击力引起丧生者很多。由于汽车前面 相似文献
997.
Zhang Xueyong Phillip M Banks P.J. Larkin 《中国农业科学》2000,(1):56-62
Z1, Z2, Z3, Z4, Z5 and Z6 are alien addition lines to wheat involving Thinopyrum intermedium chromosomes. We have characterized the Thinopyrum intermedium chromosomes or segments in these lines using multi-color florescence in situ hybridization. The probes used included total genomic DNA of Pseudoroegneria stipfolia (St) and cloned probes of highly tandem repetitive DNA pSc119. 2 and pAs1. Disomic addition lines Z1, Z2 and Z6 have the same single pair of alien chromo-somes carrying the resistant gene(s) to barley yellow dwarf virus (BYDV). This alien chromosome is a St/E translocation; within the long arm, there is a big insertion of an E-genome chromosomalsegment (30%). Disomic addition line Z3 carries one pair of St/E Robertsonian translocation chromosomes ; on the short arm (E) there is a nuclear organizer region, which expresses in some cells. In Z5, the added chromosome is one pair of translocated chromosomes. Chromosomes 2D, 3D and 3Stwere involved in the translocation with great possibility〔2IS · 3DL (0. 47) - 3StL (0. 53)〕. The St segment is responsible for resistance to leaf and stem rusts. Addition line Z4 also carries the translo cated chromosome found in Z5, but in addition carries one pair of 7AS (0. 64) - 7StS (0. 36) · 7StL translocation chromosomes. The 7St fragment bears the stripe rust resistance, and replaces the normal 7A. All of the translocations in Z1, Z2, Z6 and Z3 existed in one of their parents, the wheat Th. intermedium partial amphiploid, Zhong 5. The two wheat-Th. intermedium translocations in Z4 and Z5 occurred during the backcrossing of Zhong 5 to the other wheat varieties in the development of the addition lines. Spontaneous homoeologous translocations showed a close genome relationship between wheat and Th. intermedium. This paper also demonstrated the potential of highly repetitive sequences DNA in verification and characterization of translocation chromosomes. 相似文献
998.
Four cucumber (Cucumis sativus L. ) inbred lines with different resistances to temperature stress were used in this experiment. The seedlings of line Q10 and Q21 that have high resistance to chilling stress also have high resistance to heat stress. The seedlings of line T94 and T55 that have lower resistance to chilling stress also have lower resistance to heat stress. It seems that the resistance of cucumber seedlings to different temperature stresses was similar. The influences of chilling and heat stress on the germination ability of cucumber seeds were different. Under the chilling stress, the germination percentage decreased less, and the germination velocity decreased more,so the germination index decreased significantly. Under the heat stress, the germination percentage and velocity of the seeds with high resistance decreased less and those of the seeds with lower resistance decreased more. The differences among the lines became more evident under the extreme heat condition. The content of chlorophyll decreased under the different temperature stresses, the content of chlorophyll a decreased more than that of chlorophyll b, so the value of chlorophyll a/b decreased.The temperature stress inhibited the photosynthesis of cucumber seedlings significantly. After chilling or heat treatment, the net photosynthetic rate (Pn) decreased remarkably. With the stomatal conductance (Gs) decreased, the stomatal limited value (Is) decreased, the intercellular CO2 concentration (Ci) increased, and both the apparent quantum efficiencies (AQE) and the carboxylation efficiencies (CE) decreased. Results showed that the non-stomatal factors were the main causes of Pn decrease, and the photosynthetic mechanism was destroyed remarkably. 相似文献
999.
Zhou Wei Wang Hong Zhao Linping Lin Bao 《中国农业科学》2000,(1):90-97
Field trial, pot experiment with 45Ca tracer, plant analysis were used to investigate the characteristics of calcium uptake by young fruit of apple and its regulation by IAA, GA and NAA. The results indicated that calcium should be applied directly on the surface of young fruits because calcium applied on leaves could be hardly transfered to fruits. The proper Ca applying period was the first month of young fruits formation, and the proper concentration of CaCl2 applied was 0. 5%. Applying Ca directly on the surface of young fruits could increase the weight and quality of fruits. The process of transfering Ca2+ from fruit surface into pulp tissue could be accelerated by IAA, GA or NAA, which also led to an increment on 2% HOAc extractable Ca. Meanwhile, the Ca existed in the stalk and leaves could be strongly transported into fruits by applying IAA on the fruit surface, resulting in too much accumulation of Ca in fruit and bad quality of fruit, while no such sighs were observed with GA or NAA. 相似文献
1000.
2000年7～8月,细毛羊主产区内蒙古和新疆分别在呼和浩特市和南京羊毛市场举办了细羊毛拍卖会.在呼和浩特,拍卖成交313t,最高拍卖价为40元/kg(为净毛价,下同),平均成交价格31.3元/kg,折污毛价为13.9元/kg,比同期社会收购价高2.9元/kg.在南京羊毛交易市场,新疆细羊毛生产者协会组织近1 000t细羊毛进行拍卖,最高价43.5元/kg,平均成交价格31.5元/kg,比同期社会收购价高4～5元/kg.通过组织国产羊毛拍卖,使国产羊毛的交易出现了好的势头,带动国产羊毛价格的上升,7月份羊毛价格比1999年同期上升15.4%,使牧场增效、牧民增收.羊毛价格的上升,带动细毛种羊的旺销,内蒙古、新疆的重点种羊场,细毛种羊销售一空,细度在66支以上的种羊价格在5 000～10 000元/只,这种状况是近10年来没有的. 相似文献