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51.
采用观察法和问卷调查法对贵州师范大学宝山校区绿地进行使用状况评价,主要包括植物造景分析、园林配套设施情况、行为活动分析,行为痕迹分析。总结该校园绿地的优缺点,并提出合理的改建方案。 相似文献
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农机技术推广是农机化工作的重心。当前围绕农业产业化发展做好农机技术推广工作,是推进农业现代化和新农村建设的需要。根据池州市贵池区农业产业化发展实况,在水稻生产机械化取得一定成果和经验的基础上,应将油菜、茶叶、棉花等优势经济作物产业化发展与农机化技术发展同步推进。同时对农机技术推广还须建立强有力的配套措施予以支持:充分发挥基层农机推广机构的作用,以农机大户及产业基地为依托,强化农机与农艺结合,农机购置补贴等惠农政策要向重点对象倾斜。 相似文献
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Suckling both, or only one contralateral mammary gland during 15 days postpartum was utilized to study lactogenic hormone binding to mammary microsomal membranes and quantitative mammary morphology in ewes. Binding of radiolabeled human growth hormone was specific for lactogenic hormones. Non-radiolabeled human growth hormone, ovine and bovine prolactin and human placental lactogen effectively competed with radiolabeled human growth hormone for binding sites but ovine and bovine growth hormone were completely ineffective. Specific binding of radiolabeled human growth hormone to 600 μg of membrane protein averaged 23 ± 3% in all lactating glands. Neither days postpartum nor treatment of contralateral mammary glands substantially altered hormone binding in lactating glands. Specific human growth hormone binding (6 ± 0.5%) in non-suckled glands (15 days postpartum both udder halves) was significantly lower (P<0.01) than in lactating tissue but only a moderate and variable reduction in specific binding was measured in membranes from glands non-suckled for 15 days but contralateral to a suckled gland (14 ± 4%). Specific binding was approximately doubled in assays with 600 compared with 300 μg of membrane protein and the pattern of binding among variously suckled glands was not changed by treatment of membranes with 4 M MgCl2 prior to assay. Most secretory cells from all lactating glands had rounded, basally displaced nuclei, apical fat globules, secretory vesicles and abundant densely stained basal cytoplasm (ergastoplasm). Alveolar lumenal area was maximal (50% of tissue area) and stromal tissue area was minimal. After 15 days of non-suckling (both udder halves) mammary cells were engorged with lipid, ergastoplasm was reduced and nuclei were irregularly shaped and randomly displaced compared with lactating tissue. In addition, lumenal area was reduced and stromal tissue more evident. Lack of suckling for 5 days had little apparent effect on mammary cytology. Like lactogenic hormone binding, mammary tissue morphology was only moderately altered by 15 days of non-suckling when the remaining gland was suckled. RNA concentration was lowest (2.1 ± 0.3 mg/g) in mammary tissue from ewes in which neither gland was suckled for 15 days postpartum but non-suckling interval had no significant effect when contralateral glands were suckled. DNA concentration was not significantly influenced by suckling treatments. Relative lactogenic hormone binding closely corresponded to changes in cytological and biochemical indices of secretory cell function. 相似文献
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分析了西部地区肉牛产业化发展的限制因素,提出了加速我国西部地区肉牛产业化发展的对策与思路,推行品种良种化、技术先进化、管理企业化的生产模式,促进肉牛生产向优质、高产、高效和持续性的产业化方向发展。 相似文献
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Kathleen E. Rodgers Marcia H. Grayson Toshiko Imamura Bruce H. Devens 《Pesticide biochemistry and physiology》1985,24(2):260-266
Oral administration of O,O,S-trimethyl phosphorothioate (OOS), an impurity present in technical formulations of malathion, has been shown to be associated with a high incidence of pneumonia in rats and to be highly immunosuppressive in mice. Based on these findings, an in vitro model was established to study the effect of this and other organophosphorus compounds on murine cytotoxic T-lymphocyte (CTL) responses. The organophosphorus compounds were tested for their ability to block in vitro generation of CTL responses to alloantigen and/or the expression of these cytotoxic responses. Responses were generated in C57Bl/6 (H-2b) spleen cells to mitomycin C-blocked P815 (H-2d) tumor cells. The cytotoxicity of the cultured splenocytes to P815 target was measured using a 4-hr chromium release assay. These data demonstrated that malathion was able to block the ability of splenocytes to sensitize to P815 at concentrations as low as 25 μg/ml, but was not able to block the expression of cytotoxicity by mature killer T cells. The same was true for OOS which had been activated by preincubation with rat liver postmitochondrial supernatant (PMS). Activated OOS blocked the generation of CTL responses at concentrations as low as 75 μg/ml while having no effect on mature cytotoxic cells. In fact, both malathion and activated OOS were no longer able to suppress CTL responses if treatment was performed as early as 24 hr after exposure to antigen. Additionally, it was demonstrated that when malathion was preincubated with PMS it was no longer suppressive and that OOS without activation failed to suppress CTL responses. 相似文献
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本文总结了加快图书馆分馆建设的重要性和必要性,阐述了加快分馆建设的目标、基本条件和对策,指出多校区馆藏文献资源共享是现代图书馆文献资源建设的发展趋势。 相似文献
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吴华 《安徽农业大学学报》2007,(3):44-47,136
食品产业化兴农战略, 就是把食品产业作为农业的龙头, 以此振兴农业的战略。其核心思想是中国农业必须走变农业大国为食品大国的道路。这一战略的必要性在于, 可以提高农业的经济效益, 是富农之路; 可以推动农业工业化和城镇化的进程, 是振兴农业之本。战略实施也具有可行性, 国际国内市场对食品的需求是其发展的根源, 食品产业与三农的天然联系是其生存和发展的丰厚底蕴。该战略在操作上, 组织形式是农产品基地加乡镇企业, 资金来源主要是乡镇企业积累、融资和政府注入资金。发展食品产业化, 可走发掘传统和扩展创新之路 相似文献