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111.
研究了哈茨木霉T2-16在改良后的GPF培养基中培养所获得的发酵产物,对豇豆根瘤菌菌株耐逆性及对抗生素抗性等多个表型性状的影响。结果表明,经该发酵产物处理后,供试的一些根瘤菌菌株的耐高温、耐盐碱能力有所提高,对一些抗生素的抗性也有一定的增加,显示了木霉发酵产物在提高土著根瘤菌固氮活性方面的潜能。  相似文献   
112.
大学生是民族栋梁、国家未来,他们的健康成长不单维系着家庭幸福、人民期望,更直接关系着社会安定、国家兴衰。文章紧扣大学生心理健康主题,从发现问题、提出问题、探讨问题、解决问题人手并针对问题进行相关研究;从社会学、心理学、心理健康教育、全民精神卫生理念、探索矫正心理问题等方面去展开阐述与论证。突出了教育工作者的职能与大学生心理问题研究的紧迫性与重要性。旨在呼吁社会学家、心理学家、教育家、医学家以及全社会关心重视大学生心理健康教育问题。  相似文献   
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木材采运生产工作是事故多发的环节,从统计学角度,分析事故原因,探讨避免事故,安全生产的有效途径。  相似文献   
116.
Momen  B.  Anderson  P.D.  Sullivan  J.H.  Helms  J.A. 《New Forests》2004,27(3):303-313
A common objective in commercial reforestation is to plant seedlings that will produce superior adult trees. Long forest management planning horizons and life spans of most forest trees complicate the prediction of growth and performance of adult trees originating from planted seedlings of unknown genetic origin. We used multivariate statistics to identify and rank a set of seedlings characteristics that could predict the performance of mature trees in Pinus ponderosa. Results indicated that metabolic heat rate (q), a measure of total metabolism, of one-year-old foliage during the peak growth in May, was the most important seedling characteristic that predicted mature-tree performance. Increased metabolic heat rate in seedlings corresponded with greater vigor of mature trees. Additionally, seedling basal stem diameter (D), height (H), and needle length (NL), measured in November, were, in order of importance, other variables that defined the vigor class of the mature clones. However, these seedling morphological characteristics correlated negatively with vigor classification of the mature clones, contradicting the notion that greater D and/or H during the seedling stage may indicate a greater vigor at maturity.  相似文献   
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We identified clinical disorders of all 200 city-dwelling cart pulling male camels attending the Veterinary Teaching Hospital, University of Agriculture, Faisalabad, Pakistan during a 7-year period (1993–1999). Data were collected prospectively on a predesigned form and collated. Diagnoses of different diseases/disorders were based on clinical examination supplemented with relevant laboratory tests. A total of 463 entries of 34 different clinical diseases/disorders were recorded. Sarcoptic mange (35% of 200 camels) followed by anhidrosis (23%) and trypanosomosis (19%) were the three most frequently encountered disorders. The body system most often involved was the integument (31%) followed by gastrointestinal (21%), locomotory (12%), thermoregulatory (6%), blood (6%), urogenital (6%), lymphatic (3%), nervous (3%), respiratory (3%) and ocular (3%).  相似文献   
118.
AIM: To investigate the role of intestinal endotoxemia (IETM) in insulin resistance (IR) and cognitive impairment, and to explore the protective mechanisms of glycine in rats with high-fructose diet. METHODS: The rats in model group were fed with 8% fructose water, and the rats in intervention group were fed with water containing 8% fructose and 1% glycine. The body weight and systolic pressure were measured monthly. After 8 months, plasma glucose, plasma lipids, glucose tolerance and plasma endotoxin (LPS) were detected. Plasma insulin, pro-inflammatory cytokines in plasma and cerebral cortex were determined by ELISA, and HOMA-IR was also calculated. The molecules of insulin signaling pathway in cerebral cortex were determined by Western blotting. The cognitive functions of the rats were tested by Morris water maze. RESULTS: The weight gain in model group was increased from the 3rd month to the 6th month, and systolic pressure was increased after the 3rd month as compared with control group. Glycine significantly reduced the weight gain in the 4th month and the 6th month, and significantly reduced the systolic pressure from the 4th month to the 6th month. Meanwhile, glycine partly attenuated dyslipidemia and glucose intolerance, and lowered the levels of plasma LPS, plasma insulin, HOMA-IR and pro-inflammatory cytokines in plasma and cortex. Furthermore, glycine attenuated the abnormal expression of insulin signaling proteins and cognitive impairment. CONCLUSION: Long-term fructose diet induces the rats to peripheral and neuronal IR, which accompanies IETM and low-grade inflammation. Glycine attenuates IR and cognitive impairment by lowering IETM.  相似文献   
119.
Dogs do not appear to progress from obesity-induced insulin resistance to type 2 diabetes mellitus. Both postprandial hyperglycemia and postprandial hypertriglyceridemia have been proposed to cause or maintain beta cell failure and progression to type 2 diabetes mellitus in other species. Postprandial glucose, triglyceride, and insulin concentrations have not been compared in lean and obese dogs. We measured serum glucose, triglyceride, and insulin concentrations in nine naturally occurring obese and nine age- and gender-matched lean dogs. After a 24-h fast, dogs were fed half their calculated daily energy requirement of a standardized diet that provided 37% and 40% of metabolizable energy as carbohydrate and fat, respectively. Fasting and postprandial glucose and triglyceride concentrations were greater in the obese dogs (P < 0.001), although the mean insulin concentration for this group was five times greater than that of the lean group (P < 0.001). Most of the 0.6 mM (11 mg/dL) difference in mean postprandial glucose concentrations between lean and obese dogs was attributable to a subset of persistently hyperglycemic obese dogs with mean postprandial glucose concentrations 1.0 mM (18 mg/dL) greater than that in lean dogs. Persistently hyperglycemic obese dogs had lower triglyceride (P = 0.02 to 0.04) and insulin (P < 0.02) concentrations than other obese dogs. None of the dogs developed clinical signs of diabetes mellitus during follow-up for a median of 2.6 yr. We conclude that pancreatic beta cells in dogs are either not sensitive to toxicity because of mild hyperglycemia or lack another component of the pathophysiology of beta cell failure in type 2 diabetes mellitus.  相似文献   
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