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1.
文章通过对田园综合体的概念进行介绍,找出广西田园综合体发展情况和存在的问题,最后 提出解决广西田园综合体存在问题的对策和建议,从而促进广西农业的快速发展,带动当地经济稳步 提升。  相似文献   
2.
通过在太行山低山丘陵区的试验研究,系统地总结了在干旱山地人工种草从引种栽培的一系列综合配套技术,从一个侧面反庆子干旱山地综合治理中,牧草与林果的复合栽培在培肥土壤,改良低产农田和提高果园生产力等方面的作用;为在太行山区开展人工种草提供了依据。  相似文献   
3.
变叶海棠种群多样性的形成与分化研究   总被引:9,自引:2,他引:9  
 采用杂种指数和形象化散点图法, 探明了变叶海棠以兼性无融合生殖方式与陇东海棠和花叶海棠产生渗入杂交变异, 又以无融合生殖方式保持新产生变异的遗传, 经过数千万年的世代繁衍,形成现今这样极其复杂多样的渗入杂交群体, 该群体为3 个种的杂交复合体。由于杂种的全部或部分能育子代中发生的基因重组和增加基因的突变, 丰富了物种的基因库, 从而深入的揭示了变叶海棠具有多种高抗性的遗传机理。在变叶海棠居群内保护或栽植适量的陇东海棠和花叶海棠, 对于保持和促进变叶海棠多样性的形成与分化具有重要意义。  相似文献   
4.
张帅  曾鑫年  骆悦 《植物保护》2004,30(6):11-14
线粒体复合体Ⅰ呼吸抑制剂不仅在医药上有着重要的研究价值,在农药方面也有着特殊的意义。这类药剂的作用机制比较特殊,害虫不易产生抗性,是一类非常有前途的杀虫药剂。从植物,微生物等生物体中发现了许多线粒体复合体Ⅰ呼吸抑制剂,如鱼藤酮、粉蝶霉素A、辣椒碱,番荔枝内酯、myxalamid等,它们可以作为农药的先导化合物进行药物合成。根据不同的作用方式,线粒体复合体Ⅰ呼吸抑制剂可分3种类型,分别以粉蝶霉素A、鱼藤酮、辣椒碱为代表。  相似文献   
5.
Ecological ravages, environmental pollution, and the developmental problems of regional ecology, economy, and society are not geographical restrictions. The synergistic development of the ecology-economy-society system in forestry was quantitatively assessed by system theory and synergistic dynamic models, illustration of the metering principle and corresponding theory, assessing and quantizing synergistic development status of ecology-economy-society system, and the orderliness of the subsystem of the last decade. The orderliness of the ecology and ecological subsystems developed unstably with an increasing trend. The eco-environment construction and eco-conservation achievement of forestry in China are effective and need to be maintained. The industry structure should be improved to promote the growth of the forestry economy. The society subsystem development is increasing but is not at a high level, which indicates that the public demand to ecological service was not satisfied. The theoretical analysis and numerical examples show that the development of the forestry system has a good development state. The synergy changes of forestry system in the 0 to 0.951 range, which is in the intermediate degree of synergy during this period. It still needs much improvement on efficiency of synergy. The orderliness and the relationship among the subsystems of forestry should be improved in future.  相似文献   
6.
总结近年铋系列半导体光催化剂的制备、种类和光催化反应机理等的研究进展,并展望了铋系列半导体光催化剂未来的发展方向.  相似文献   
7.
杨玉帅  李泽  金天明  杨升 《中国畜牧兽医》2021,48(11):4094-4104
为了提高难溶性药物烯丙孕素(altrenogest,ALT)的水溶性,本试验采用冷冻干燥法来制备烯丙孕素-羟丙基-β-环糊精(ALT-HP-β-CD)及其衍生物2,6-二甲基-β-环糊精(DIME-β-CD)包合物载药体系,并对ALT的线性关系和专属性、仪器的精密度以及包合物的回收率和稳定性进行了测定。以包合物的收率和包合物中ALT的包合率为评价指标,采用正交试验设计优选2种包合物的最佳制备条件,并使用傅里叶变换红外光谱法、热重分析法和显微镜成像法对所制得的ALT包合物进行表征分析,采用溶解度法测定包合物中ALT的溶解度。结果表明,ALT在1~12 μg/mL范围内具有较好的线性关系且专属性良好,仪器的精密度良好;加入0.1、0.2和0.3 mL ALT标准液的ALT-HP-β-CD包合物的平均回收率分别为97.78%、99.38%和99.90%,加入0.1、0.2和0.3 mL ALT标准液的ALT-DIME-β-CD包合物的平均回收率分别为93.86%、97.72%和94.93%;ALT-HP-β-CD包合物的最佳制备工艺为在55 ℃条件下,ALT与HP-β-CD的投料摩尔比为1∶7,包合时间为4 h,溶液pH为8,溶剂水的加入量为110 mL/g药物;ALT-DIME-β-CD包合物的最佳制备工艺为在55 ℃条件下,ALT与DIME-β-CD的投料摩尔比为1∶4,包合时间为4 h,溶液pH为9,溶剂水的加入量为100 mL/g;经傅里叶变换红外光谱法、热重分析法和显微镜成像法表征,证实成功制得包合物;溶解度试验得出包合物的溶解度分别约为ALT原药的1 012和1 354倍,表明两种包合物均可有效增加ALT的溶解度。本试验包合物的制备方法简单,条件温和,易于产业化生产。  相似文献   
8.
This experiment was conducted to investigate the effects of complex nutritional regulation additives on growth performance, slaughter performance and serum biochemical indexes of grazing sheep in cold season.A single factor random block design was used and 48 grazing ewes with the average weight (28.01±1.70) kg and 7 months old were randomly divided into 4 groups:Group Ⅰ without supplement;Group Ⅱ with concentrate;Group Ⅲ with concentrate+complex formulation 1 (0.30% malic acid, 0.06% cysteamine, 0.08% saccharicterpenin);Group Ⅳ with concentrate+complex formulation 2 (0.60% malic acid, 0.12% cysteamine, 0.16% saccharicterpenin)with 3 replicates per group and 4 grazing ewes per replicate.The results showed that:①The final weight of group Ⅲ was the highest and higher than group Ⅱ and Ⅳ by 6.26% (P>0.05)、3.69% (P>0.05), respectively.The average daily gain of group Ⅲ was highest, and higher than group Ⅱ and Ⅳ by 26.32% (P<0.01)、5.74% (P>0.05) respectively.②Comparing with group Ⅱ, the slaughter rate of group Ⅲ was increased by 4.68% (P>0.05).Compared with groupⅠ, Ⅱ and Ⅳ, the meat percentage of group Ⅲ was increased 18.46% (P<0.05), 10.97% (P>0.05) and 4.40% (P>0.05), while the net meat weight of carcass in group Ⅲ was increased by 49.74% (P<0.01), 13.22% (P>0.05) and 18.27% (P<0.05), respectively.Compared with groupⅠ, Ⅱ and Ⅳ, the net meat rat of carcass in group Ⅲ was increased 10.42% (P<0.01)、6.00% (P>0.05) and 3.37% (P>0.05), respectively.③There was a rising trend as the order of groupⅠ, Ⅱ, Ⅳ and Ⅲ in serum glucose, Ca, P, HDL, LDL, GPT and IgG, while A/G and TG showed a decreasing trend.Based on the above results, in this trial, supplementing complex nutritional regulation additives had good effects on growth performance, slaughter performance and serum biochemical indexes of grazing sheep in cold season.And supplementing complex formulation group 1 (group Ⅲ) was the best.  相似文献   
9.
1-day-old SPF chickens and commercial Jingfen chickens were vaccinated with IBD immune complex(IC) vaccine, NDV La Sota vaccine were inoculated simultaneously every one week and every two weeks.NDV La Sota immunization alone was as the control group.At the 2nd, 3rd, 4th and 5th week post inoculation, blood samples were taken and the ND HI antibody were tested.Experimental chickens were challenged with high virulent NDV at the 5th week post inoculation, the protective rate of each group was calculated.The results showed the ND HI antibody were not significant different in the combined immunization of IBD IC vaccine priming and NDV La Sota vaccine boost and NDV La Sota vaccine alone immunization (P>0.05).The results indicated that IBD IC vaccine has no immunosuppression on NDV La Sota vaccine in SPF chickens and commercial Jingfen chickens.  相似文献   
10.
BACKGROUND: Recombinant feline interferon-omega (rFeIFN-omega) was tested as a treatment option for cats with fibrosarcoma to assess safety and feasibility. HYPOTHESIS: Treatment with rFeIFN-omega in cats with fibrosarcoma is safe and feasible. ANIMALS: Twenty domestic cats. METHODS: In an open-labeled uncontrolled clinical trial 12 injections of 1 x 10(6) U/kg rFeIFN-omega were administered over a 5-week period: the 1st through 4th injections were given intratumorally, and the 5th through 12th injections were administered subcutaneously at the tumor excision site. Wide surgical excision of the tumors was carried out after the 4th injection and before the 5th injection of rFeIFN-omega. A Common Terminology Criteria for Adverse Events (CTCAE) analysis was conducted. Flow cytometry of fibrosarcoma cells after incubation with rFeIFN-omega and recombinant feline interferon-gamma was performed to assess the biological effect of rFeIFN-omega. RESULTS: Changes in blood cell count, increases in serum aspartate-amino-transferase activity, serum bilirubin concentration, serum creatinine and serum electrolyte concentrations, weight loss, anorexia, increased body temperature, and reduced general condition were observed but were mostly minor (grade 1 and 2) and self limiting. Eosinophilia (P = .025), neutropenia (P = .021), and weight loss (P < .001) were statistically correlated with rFeIFN-omega-treatment (analysis of parameters before treatment and after 3 injections of rFeIFN-omega). Flow cytometry of 5 unrelated feline fibrosarcoma cell lines showed increased expression of major histocompatibility complex (MHC) class I molecules (P = .026) in response to in vitro incubation with rFeIFN-omega, whereas expression of MHC class II molecules was not affected significantly. CONCLUSIONS AND CLINICAL IMPORTANCE: RFeIFN-omega for the treatment of feline fibrosarcoma is safe, well tolerated, and can be easily performed in practice. To assess the efficacy of the treatment, it should be tested in a placebo-controlled trial.  相似文献   
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