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91.
根据自然地理分异规律、社会经济技术原理、生态学原理,分析了四川省的水土流失概况,提出了川中丘陵、盆周山地区、川西南干热干旱河谷区、川西北高山高原区的退耕还林模式。  相似文献   
92.
为了建立一种快速、简便、敏感、特异地检测动物病理材料中布氏杆菌的方法,选用四种标记抗体法,对5种共15个生物型的布氏杆菌,以及大量与流产有关或常常污染病理材料的对照细菌,分别进行了纯菌、感染实验动物及牦牛组织材料的染色检查,并与柯氏染色法及细菌分离培养法进行了比较。结果表明,四种方法对于各种材料中的布氏杆菌(粗糙型犬布氏菌除外)均呈阳性反应,而绝大多数对照菌均呈阴性反应。其中尤以SPA法染色背景更为清晰,非特异性反应更少。这些方法既简便、快速,检出率也较高。对于布氏杆菌病的诊断和疫情监测,是很有价值的。  相似文献   
93.
The Luntiang Kamaynilaan Project (Metro ManilaGreening Project) launched in 1988 planted trees inmajor thoroughfares, center islands, school premisesand other idle public lands, was basically a governmenteffort. When the funds ran out, the project also fizzledout. In both projects however, it is evident that the keyfactor is peoples participation.Gaining lessons from the past two projects, thegovernment established a collaborative effort ofgovernment and non-government organizations. TheCl…  相似文献   
94.
双孢菇的营养价值及栽培技术   总被引:1,自引:0,他引:1  
1营养价值及保健功能双孢菇具有食用、保健功效。蘑菇的菌肉肥嫩,味道鲜美,营养丰富。每100g鲜菇中含蛋白质3.7g,脂肪0.2g,糖3.0g,纤维素0.8g,磷110g,铁0.6mg,灰分0.8g,VC 3mg,VB10.1mg,VB20.35mg,烟酸149mg。蘑菇既是一种高档的菌类蔬菜,又是一种有保健作用的营养食品。含高蛋  相似文献   
95.
针对采暖设计中的一些问题,提倡以自然科学理论指导采暖设计和设计上的创新,建议采暖设计规范化。  相似文献   
96.
绢丝昆虫茧丝蛋白酶抑制剂含量的比较分析   总被引:3,自引:3,他引:0  
以 6种绢丝昆虫的茧壳为材料 ,对茧丝蛋白酶抑制剂的含量及热稳定性进行了研究。结果表明 :家蚕品种间茧丝蛋白酶抑制剂的含量差异极显著 ,外层丝中含量较多 ,F1代的含量呈双亲中间型 ,偏向于含量较多的亲本 ,雌雄间含量无显著差异 ;家蚕茧丝蛋白酶抑制剂对热稳定性较强 ;天蚕绿茧、野蚕的茧丝中有少量的蛋白酶抑制剂存在 ,蓖麻蚕的茧丝中有微量蛋白酶抑制剂存在 ,天蚕黄茧、柞蚕茧、樗蚕茧的茧丝中基本无蛋白酶抑制剂存在。  相似文献   
97.
中草药饲料添加剂饲喂泌乳牛的效果   总被引:18,自引:0,他引:18  
试验选用20头体重、胎次、产犊天数、产奶量基本一致的荷斯坦泌乳母牛,按随机分为两组,即对照和试验。经过60天的饲养试验。结果表明:与对照相比,试验组奶牛日产奶量平均提高了4.3千克,乳脂率提高0.171个百分点,经济效益2.57元/头日。  相似文献   
98.
This study evaluates the ability of selenium (Se) supplementation to prevent experimental copper (Cu)-induced hepatocellular damage. Weanling male Fischer 344 rats were randomly assigned to groups of 15, 3 groups (A,B,C) were fed Cu-loaded diets (containing 2000 microg/g copper, added as CuSO4) and different levels of Se (added as Na2SeO3 x 5H2O) as follows: A) Cu-loaded/Se adequate diet (0.4 microg/g Se, fed basis); B) Cu-loaded/Se-supplemented diet (2 microg/g Se); and C) Cu-loaded/Se-deficient diet (< 0.2 microg/g). Three additional groups (D,E,F) were fed diets containing adequate levels of Cu (14 microg/g Cu, fed basis) and different levels of Se as follows: D) Cu-adequate/Se-adequate diet; E) Cu-adequate/Se-supplemented diet (2 microg/g Se); and F) Cu-adequate/Se-deficient (< 0.2 microg/g) diet. After 4, 8, and 12 weeks on the experimental diets, liver samples were processed for histology, histochemistry, metal analysis, glutathione peroxidase (GSH-Px) measurement, and quantification of malondialdehyde (MDA). Morphologic changes characteristic of Cu-associated hepatitis, without an increase in hepatic MDA levels, were seen in all Cu-loaded rats in each sampling. Similar changes occurred in rats fed Se-adequate, Se-supplemented and Se-deficient diets. This study demonstrates that Fischer 344 rats fed 2000 microg/g Cu develop morphologic changes due to Cu toxicity without evidence of lipid peroxidation. Furthermore, Se supplementation does not result in protection against Cu-induced liver injury.  相似文献   
99.
介绍了埋地输油管道新型预应务抗滑桩的构成和抗滑原理,并对其受力状况进行了分析。以某油加库外滑坡地段埋地输油管道的实际应用为例,表明采用新型预应力锚索抗滑桩保护滑坡地段的埋地输油管道不仅是可行的,而且具有较好的经济性、实用性和可靠性。  相似文献   
100.
Differences in Mycoplasma hyopneumoniae colonization were evaluated in experimentally inoculated pigs sired by 3 different boars of the same genetic line. Forty-six pigs were used, including a treatment group and positive and negative control groups. The pigs were intratracheally inoculated with an M. hyopneumoniae suspension or with Friis media as a placebo. To evaluate differences in the magnitude of colonization during a 35-day period, nasal and tracheal swabs were collected weekly and tested by nested polymerase chain reaction (N-PCR). Temperature, weight and circulating antibodies were measured for 35 days. At 11 and 35 d postinoculation the pigs were necropsied and macroscopic and microscopic lesions were determined. A section of bronchus was tested by the indirect immunofluorescence test (IFAT), scanning electron microscopy (SEM) and N-PCR. The N-PCR results from the nasal and tracheal swabs showed that the pigs sired by one boar (B3) had a distinctive colonization pattern, different from that of the pigs from the other 2 boars and from the positive controls. SEM studies demonstrated that at 35 d postinoculation a higher proportion of B3 pigs had lower numbers of mycoplasmas attached to the cilia compared with B1 and B2 offspring. No significant differences were observed in temperature and weight gain among groups by ANOVA; however, with use of a 2 × 2 table, temperature differences were observed between pigs sired by boars B1 and B2 at 4 d postinoculation. No pigs seroconverted, showed gross or microscopic lesions, or had positive IFAT results. These results provide evidence of differences in patterns of colonization between pigs sired by different boars, suggesting a possible genetic effect.  相似文献   
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