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纵坑切梢小蠹综合防治研究   总被引:6,自引:0,他引:6  
本文是纵坑切梢小蠹系统研究论文中的综合防治部分。文章根据多年的试验研究成果,首先提出了划分云南松林分蠹害程度及蠹害木的分级标准,针对林分的危害情况,采取相应的蠹害治理综合措施。蠹害治理的主要技术措施包括:1.蠹害木清理技术;2.化学农药防治技术:3.生物防治技术;4.小蠹聚集信息素引诱技术等内容。对小蠹提出了以营林技术措施为基础,清理蠹害木为主,合理施用化学农药,应用生物防治手段控制林间种群密度的防治策略。  相似文献   
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美味良药话香菜   总被引:6,自引:0,他引:6  
柴玉花 《蔬菜》2002,(1):40-40
香菜属伞形科植物,为一、二年生芜荽的带根全草,又名胡荽、香荽等,全国各地均有栽培。香菜不仅是一种蔬菜,同时也是一种天然植物香料。原产地中海东部和叙利亚等地,汉代即公元前2世纪张骞经中亚从西域将种子带入我国,其形态与芹菜相似,具有特殊的香味,清脆鲜嫩、营养丰富,在我国及东南亚各地具有民族风味的菜肴中,是不可缺少的佐料。冬令菜肴中,香菜羊肉汤、香菜牛肉汤等,鲜美可口,还是进补强身、散寒祛风的佳品。 香菜的营养十分丰富,每100g可食部分中含有水分90g、蛋白质1.7g、脂肪0.3g、糖类5.9g、粗…  相似文献   
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<正> 泥炭沼泽是一种水陆过渡性的,具有独特生态系统的自然环境。这一环境对发展国民经济与生态保护均有重大意义。泥炭沼泽在国民经济发展中主要有两大作用,其一,它是易于开发的宝贵的土地资源,其二,它蕴藏有丰富的泥炭资源。这两大资源对冷湿的高原与山区尤具特殊意义。目前许多发达国家对沼泽与泥炭资源的开发都取得了很大的进展。如日本战败后粮食奇缺,经过四五次有计划的、大规模的泥炭沼泽的开发,将其全部泥炭沼泽的50%以上,改造成高产稳产的水稻田与旱田以及部分牧场;苏联在改造泥炭沼泽、辟为牧场、棉田等方面,  相似文献   
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A case of selenium poisoning was suspected following the administration of 325 micromol selenium a day as sodium selenate (25 mg Se) for five consecutive days. The main signs were confined to changes in the integument which were loss of hair from the mane and tail, disintegration of the skin of the anus, lips, prepuce and scrotum, and separation of the hooves from the coronary corium. Periodic analyses of blood, hair and hoof parings from the sole correlated strongly with blood and identified horn and hair as important additional routes of excretion.  相似文献   
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The plasma aldosterone concentration (PAC) among clinical status groups of 23 dogs with chronic heart failure was compared at various times after diagnosis of the problem. Eighteen dogs admitted in New York Heart Association (NYHA) class IV clinical status had significant elevations in PAC (P<0.0001), when compared with clinically normal dogs. Five dogs admitted in NYHA class III status and 4 dogs that responded with a change to NYHA class III status had significant elevations in PAC (P<0.01), when compared with clinically normal dogs. In patients with NYHA class IV status, the PAC was significantly greater (P<0.01) than in patients in NYHA class III status. For patients with the poorest prognosis, ie, severe signs of NYHA class IV status, the PAC was not markedly different, when compared with that for patients with a favorable prognosis, ie, recent onset of signs of NYHA class IV status. Patients treated with captopril had significantly lower PAC after therapy (P<0.01), whereas patients treated with hydralazine had significantly higher PAC (P<0.05) after therapy. It was concluded that heart failure in the dog increases PAC, most likely because of renin-angiotensin-aldosterone-system activation, and that the increase is related directly to the clinical status of the patient. Further, it was concluded that treatment of dogs in heart failure with captopril causes a decrease in circulating PAC, whereas treatment with hydralazine causes an increase in circulating PAC.  相似文献   
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Sources of stray electrical leakage from Power Supply Authority alternating current (AC), fence energiser pulses and randomly generated pulses and spikes on 55 dairy farms in the Waikato area were identified between December 1986 and March 1988. The electrical measurements were made using a specifically designed voltmeter able to detect voltages between 0.1V and 1500V, from single voltage spikes of two microseconds or greater duration from direct current (DC) as well as 50 Hz AC. Ninety-five sources of stray voltage were identified, and 53 per cent of properties had more than one source of >0.5V. The major source was from electric fence energisers. Rotary platform parlours were among the commonest sources of random or transient voltage spikes. Leakage of AC into one or other of the components of the milk transport system such as vat, plate cooler, milk lift pump and milk line was common. Owners acknowledged the improvements in milk production, reproductive performance and growth rate of calves after reduction of the exposure of dairy cattle to stray electrical leakage. A representative summary of five case records helps define the range of improvements that may possibly be achieved.  相似文献   
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A profile of measurements of shear stress perpendicular to the San Andreas fault near Palmdale, California, shows a marked increase in stress with distance from the fault. The pattern suggests that shear stress on the fault increases slowly with depth and reaches a value on the order of the average stress released during earthquakes. This result has important implications for both long- and shortterm prediction of large earthquakes.  相似文献   
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