立式液压毛皮去脂机液压系统设计

去脂是经济动物毛皮加工的重要工序。本文介绍了去脂加工机械化作业的液压毛皮去脂机的结构、工作原理、工作特点及液压系统的设计     

甘肃省"两西"地区草地退化的成因

分析了甘肃省“两西”地区草地退化的现状，提出了两西地区草地退化的成因；（1）草地生境的脆弱性。包括地质地貌的肴弱性；水土、热量匹配差及气候变化的影响；（2）自然外营力的驱动作用，包括干旱，风蚀、水蚀、冻融、盐渍化；（3）人为因素的影响，包括过度放牧，农垦撂荒、樵采挖药，水环境恶化，采矿及工矿污染。     

施氮和修剪对混播草坪稳定性的影响

在冬季寒冷、夏季高温的北京地区气候条件下，研究了施氮和修剪对草地早熟禾与结缕草混播草坪的影响。试验处理包括：修剪高度２、３、４ｃｍ；年施氮量０、１５０、４００ｋｇ／ｈｍ２，在春、秋季各施一次。测定了草坪密度、修剪量、质量及病害程度。结果表明：修剪高度和施氮水平影响混播草坪的分蘖比例，且前者的影响程度大于后者。降低修剪高度，混播草坪中结缕草的比例增加，相反则草地早熟禾占优势。随着施氮量增加，草地早熟禾的比例增加，在修剪高度３ｃｍ、施氮量为１５０ｋｇ／ｈｍ２时，草地早熟禾与结缕草的生长趋于平衡，质量稳定，夏季病害少，可保持草坪的稳定性。     

世界栽培蕈菌的种类和分类系统

本文报道了目前人工培养菌丝体和子实体的囊菌150多种,它们属于子囊菌亚门和担子菌亚门,有4纲,14目,30科,60余属。据Ainsworth和Bisbys(1983)的《真菌字典》列出了这些属的分类系统。     

Relationship between red blood cell thiopurine methyltransferase activity and myelotoxicity in dogs receiving azathioprine

Thiopurine methyltransferase (TPMT) produces inactive metabolites of azathioprine and, in humans, has a variable amount of activity. Humans with low TPMT activity commonly develop myelotoxicity when receiving azathioprine. Our study sought to characterize the distribution of TPMT activity in a population of dogs and to determine whether the pretreatment knowledge of red blood cell (RBC) TPMT activity could predict myelotoxicity in dogs receiving azathioprine. RBC TPMT activity was measured in 299 healthy dogs, and 9 dogs that represented a wide range of enzyme activity received azathioprine at a standard therapeutic dose for 30 days. TPMT activity in healthy dogs was log normally distributed and varied over an approximately 7-fold range. Geometric mean, minimum, and maximum RBC TPMT activities were 37.1, 16.3, and 115 nmol per gram of hemoglobin (gHb) per hour, respectively. TPMT deficiency was not identified. Two populations of TPMT activity in dogs were detected by statistical modeling (commingling analysis). Dogs with intermediate TPMT activity (14-38 nmol/gHb/h) receiving azathioprine had significantly lower neutrophil counts during week 4 than during weeks 0-3, whereas those with high activity (>39 nmol/gHb/h) did not have a significant change in neutrophil count. An analysis of TPMT activity in 6 dogs with a history of azathioprine-associated myelotoxicity in a clinical setting revealed either intermediate or high TPMT enzyme activity in all dogs, suggesting that TPMT activity, as measured in RBCs, is not the sole cause of severe azathioprine-associated myelosuppression in dogs.     

红黄壤地区粮食生产持续性分析

从支持人类生存的基本需求出发,对红黄壤地区粮食生产持续性进行了农田粮食单产、区域粮食总产量及区域粮食供需平衡3个层次的分析.结果表明,红黄壤地区粮食生产持续性呈现系统层次和区域分异性,从粮食单产水平的可持续,到粮食总产量水平的弱持续,再到粮食供需系统的不可持续;沿海经济发达地区农田粮食单产持续性较高但区域粮食总产量持续性较差,西南地区农田粮食单产和区域粮食总产量均呈较弱持续性.因此对区域粮食生产持续性进行多层次综合分析,同时对区域农业资源进行综合管理是促进区域农业持续发展的保证.     

大肠杆菌(O78)菌毛油乳剂疫苗对鸡的免疫原性研究

评价了大肠杆菌(O78)菌毛油乳剂疫苗对鸡的免疫原性.鸡经皮下接种130 μg及65 μg菌毛蛋白并用同源大肠杆菌经后胸气囊攻毒 ,未免疫鸡攻毒作为阳性对照,未免疫鸡不攻毒作为阴性对照.免疫鸡可抵抗急性呼吸道感染, 因为免疫鸡:(1)与未免疫未攻毒鸡在增重上无显著区别;(2)死亡率低甚至无死亡; ( 3)在气囊、心包、肝仅有轻度病变,分值显著低于阳性对照鸡;(4)比阳性对照鸡更能清除体内的大肠杆菌.     

禽流感高免卵黄抗体的研制与应用

用禽流感Ｈ９亚型油乳剂灭活苗多次免疫产蛋鸡,获得高免蛋,并禽流感高免卵黄液,在发病初期给禽流感病鸡肌注高免卵黄液,获得了满意的治疗效果。     

植物离体培养物中鱼藤酮的分离与HPLC测定

毛鱼藤（Ｄｅｒｒｉｓ ｅｌｌｉｐｔｉｃａ （Ｒｏｘｂ．）Ｂｅｎｔｈ．）和西非灰毛豆（Ｔｅｐｈｒｏｓｉａ ｖｏｇｅｌｉｉ Ｈｏｏｋ．ｆ．）离体培养物经９：１ＣＨＣｌ３／ＭｅＯＨ溶剂提取,Ｃ－１８柱层析分离后,在室温条件下以６６：３４ＭｅＯＨ／Ｈ２Ｏ或４２：５８ＣＨ３ＣＮ／Ｈ２Ｏ为流动相,支样品进行反相柱ＨＰＬＣ分析。结果表明,毛鱼藤和西百灰毛豆的愈伤组织均能合成鱼藤酮,但含量相当低,分别为１７．４μｇ／ｇ,１．８μｇ／ｇ干重。经诱导生根分化的毛鱼藤愈伤组织鱼藤酮含量达１３６．２μｇ／ｇ干重,为愈伤组织含量的７．８倍。西非灰毛豆悬浮培养物的鱼藤酮含量虽比愈伤组织有很大提高,但还不及毛鱼藤愈伤组织含量。结果表明,植物的基因类型在次生代谢上起重要作用,同时离体组织或细胞的分化有助于鱼藤酮的生物合成。