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131.
鸭梨秋施^15N尿素的吸收与分配   总被引:32,自引:2,他引:30  
徐季娥  陈良 《园艺学报》1993,20(2):145-149
  相似文献   
132.
对1965年定植的23个柚(Citrus grandis Osbeck)品种进行了20多年的性状比较。筛选出矮化类型6个,早熟和晚熟类型各3个,丰产类型6个,品质优良类型11个。发现仅有部分柚品种富含维生素C;果汁中维生素C含量与酸含量呈明显负相关。证实长寿沙田柚中的冬瓜圈和古老钱两个选系比广西沙田柚更丰产优质;垫江白柚质优,但产量低。简述了各参试品种的利用前途。  相似文献   
133.
竹林是世界上第二大森林,它不仅再生能力强,生长迅速、成材期短、产量高,而且具有一次造林永续利用等优点,是当今保护生态环境、退耕还林(草)首选的林种。通过近些年的研究发现,它的价值不仅仅体现在山区绿化和水土保持,而且从传统的编筐织席到现在的竹、木复合板材的加工利用以及与竹笋等有关的食品、饮料的综合开发,它已经成为不少地区广大林农的一大经济支柱和经济来源。  相似文献   
134.
A field study involving 325 calves from 17 dairy herds in Saskatchewan was conducted to determine the risk of enzootic pneumonia and to assess its association with a number of factors. Two different case definitions of pneumonia were used in the analyses: the first was based on producers' treatment risk (CASE1) and the second was based on semimonthly clinical examinations of calves by the research veterinarian (CASE2). The risk of pneumonia based on CASE1 was 39% and on CASE2 was 29%. The measure of agreement between CASE1 and CASE2 at the calf level of analysis was poor (kappa = 0.24, SE = 0.02) and at the herd level of analysis was moderate (kappa = 0.40, SE = 0.12). The mortality risk from pneumonia was 1.8% and a variety of infectious organisms were isolated from pneumonic lungs. Twenty-seven percent of the calves had inadequate (total IgG < or = 800 mg/dL) levels of passively acquired antibodies as measured by radial immunodiffusion. The proportion of seropositive titers in calves within the first two weeks of age was 94% to parainfluenza 3 virus (PI3V) and bovine respiratory syncytial virus (BRSV), 73% to Pasteurella haemolytica (Ph), 68% to bovine viral diarrhea virus (BVDV), 67% to infectious bovine rhinotracheitis virus (IBRV), 46% to Mycoplasma dispar (Md), 44% to Haemophilus somnus (Hs), and 21% to Mycoplasma bovis (Mb). At the calf level of analysis and after adjusting for clustering, there was a negative association (p = 0.10) between the diagnosis of pneumonia based on CASE2 and total IgG levels and Ph titers (rPh).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
135.
从实际工程的角度出发,对电路电测方法进行了论述。在微通信工程中,需要获得障碍物的位置和高度,最合理的天线高度组合和障碍物绕射损耗等参数,为此论述了微波电路电测方法及技术要求。在大庆-秦皇岛输油管道通信工程中采用了A,B测试法进行测试,得到高度-损耗曲线。这种曲线给出相对自由空间接收电平与收,发天线高度之间的关系。在测试所得的高度-损耗曲线与断面图相结合的基础上,由绕射损耗计算公式推出了几种常见障碍  相似文献   
136.
用免疫组化A B C法对60例甲状腺病理标本进行了甲状腺球蛋白检查,结果表明源于甲状腺滤泡上皮细胞的肿瘤,均呈阳性或弱阳性反应。大部分甲状腺癌呈弱阳性反应。作者认为甲状腺球蛋白可作为鉴别甲状腺滤泡上皮细胞源性与非滤泡上皮细胞源性的良好标记。  相似文献   
137.
Total serum alkaline phosphatase (ALP) activity is the product of the combined activity of isoenzymes from a number of tissue sources. In this study, a commercially available kit for electrophoretic separation of ALP isoenzymes in an agarose gel was used to separate ALP isoenzymes in feline tissue extracts and serum. Five separate bands of ALP activity were identified. These bands were numbered 1 to 5 with band 1 having the most anodal migration. The tissue of origin corresponding to the migration position of the isoenzymes are as follows: Band 3 was the liver isoenzyme, band 4 was the bone isoenzyme and ALP isoenzymes of both intestine and kidney migrate in the position labelled band 5. Band 1 appears to be related to albumin and does not represent true ALP activity. The tissue source of band 2 (a and b) was not identified. Serum ALP activity of mature, healthy cats is primarily of liver origin. Immature cats (< 1 year of age) have a greater proportion of the bone isoenzyme in the serum.  相似文献   
138.
Two methods of administration of amphotericin B were compared for their ability to produce nephrotoxicity in 12 dogs. Six dogs received six alternate day doses of amphotericin B: 1 mg/kg administered as a rapid bolus in 25 mL 5% dextrose in water. Another six dogs received alternate day treatments of the same dose of amphotericin B in 1 L 5% dextrose in water over 5 h. Both treatment groups experienced significant reductions in glomerular filtration rate, as measured by inulin clearance, 24 h endogenous creatinine clearance, serum creatinine and serum urea. This reduction in glomerular filtration rate was most marked in the group receiving the drug as a rapid bolus. The inulin clearances decreased from 3.54 +/- 0.30 mL/min/kg (means +/- SEM) on day 0 to 1.15 +/- 0.25 mL/min/kg on day 12 in the slow infusion group and from 3.24 +/- 0.25 mL/min/kg on day 0 to 0.46 +/- 0.11 mL/min/kg on day 12 in the rapid bolus group. Renal lesions characteristic of amphotericin B administration were observed in all dogs tested. The dogs which received amphotericin B as a rapid bolus had a significantly greater number of tubular lesions than the slow infusion group. Systemic side effects, such as vomiting, diarrhea and weight loss, were observed in both treatment groups but were most severe in the rapid bolus group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
139.
The purpose of this study was to determine whether there were differences in skeletal muscle properties in the hindlimb muscles of different types of dogs. Muscle samples were obtained from the gracilis, sartorius cranial head, sartorius caudal head and tibialis anterior muscles of mixed-breed and hound-type dogs and Beagles. Fiber type, fiber size and capillary morphometry determinations of each muscle from each dog were made from sections stained for myofibrillar ATPase activity. Individual animals were bilaterally symmetric for all measured variables. Fiber type, fiber size and capillary geometry varied between dogs of a given type and muscles within a given dog. There were no differences between dog types for fiber type or fiber size; significant variation in log(muscle)/log(body) mass ratios between dog types was observed for all muscles. The results indicate that for a given muscle, significant variation can occur in skeletal muscle characteristics between different types of dogs and that these differences can be independent of differences in exercise history.  相似文献   
140.
刺槐抗旱造林技术的研究   总被引:2,自引:0,他引:2  
在不同类型区及不同立地条件下,研究了提高剌槐成活率和生长量的抗旱造林技术。结果表明,采用径流集存、吸水剂蘸根、覆膜覆草及幼林地少量施肥技术,均可显著提高剌槐造林成率与生长量,提高幅度为2.0%-8.9%和14.5%-87.5%。采用混草技术可增收可观的优质牧草,经济效益和生态效益显著。  相似文献   
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