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1.
赵宏波  郝日明  胡绍庆 《园艺学报》2015,42(9):1760-1770
桂花(Osmanthus fragrans Lour.)野生资源有非常丰富的性状和遗传变异,但目前被过度开发、破坏,导致分布范围急剧缩小,种群规模和数量锐减,生境片断化严重。以往的文献认为桂花起源于喜马拉雅山脉东段,即中国的西南地区;然而随着野生种群在湖南、浙江和福建等地被陆续发现,关于桂花自然分布的问题需要重新审视。作者在大量野外调研的基础上,结合前人研究结果,对桂花的自然分布和种群特征等进行了总结和概括,分析了野生资源与品种起源的关系,以期为桂花野生资源的有效保护和高效利用提供参考。  相似文献   

2.
Residential properties in the United States represent a considerable amount of land area and contain substantial tree cover. Homeowners are important decision makers in the management of city trees because they influence the structure of urban forests, and ultimately, ecosystem service potential. To better understand the perceptions, knowledge, and practices of homeowners regarding residential tree preservation, we surveyed owners of newer versus older homes in a midwestern suburb in the United States. We found that newer homeowners were younger, wealthier, and less knowledgeable about the natural aspects of their property. During the redevelopment process, they relied on professionals to make major decisions regarding tree preservation. In contrast, owners of older homes often identified as retirees and gardeners, had more knowledge of the natural aspects of their property, and were more likely to hire an arborist. Regardless of these differences, both homeowner groups expressed equal appreciation for nature, planted, pruned, and mulched their trees, experienced tree loss, hired landscaping and tree care professionals, and communicated with the City’s Forestry Section. The results of our study further clarify the role that homeowners play in decision-making during development and highlight the important relationships that exist between homeowners and urban forest professionals.  相似文献   

3.
锥栗种仁发育期叶片与果实矿质元素含量变化   总被引:1,自引:0,他引:1  
以‘长芒仔’锥栗为试材,对其种仁发育期营养枝叶片、结果枝叶片及果实(种仁、刺苞、果皮 + 种皮)中N、P、K、Ca、Mg、Mn、Fe、Zn、Cu 矿质元素含量及果实不同组织质量变化进行分析。结果表明:坚果从幼胚发生期至成熟期为种仁发育的关键时期,坚果、种仁和淀粉干质量较前期都有显著增长,分别增加了6.14 g(92.4%)、4.97 g(99.43%)及3.82 g(99.92%)。在种仁发育期,营养枝及结果枝叶片中Cu 含量呈显著下降变化,P、Zn 含量波动上升;果实刺苞中Ca、Fe、Cu 含量显著下降,Zn 含量上升后下降,其余元素变化甚微;果皮 + 种皮中N、P、K、Mg、Cu 含量前期变化甚微,后期显著下降,Ca、Zn 含量先增加后降低;种仁中N、P、K、Ca、Mg、Mn、Fe、Zn、Cu 含量均呈降低变化,种仁中各元素总量均呈显著上升趋势,在采收前1 周Ca、Mg、Mn、Fe、Cu 总量呈明显降低。种仁内淀粉总量与结果枝叶片及营养枝叶片中Cu 含量,刺苞中Cu 含量,果皮 + 种皮中K、Mn 含量呈显著负相关;与刺苞中Fe 含量,果皮 + 种皮中P、Mg、Cu 含量呈极显著负相关;而与种仁中的N、P、K、Mg、Mn、Fe、Zn、Cu 总量极显著正相关。  相似文献   

4.
草莓品种对蚜虫的抗性机制   总被引:1,自引:1,他引:0  
为探讨草莓品种对蚜虫的抗性机理,以5个常规草莓品种为试材,通过调查、测定大棚内蚜虫自然发生动态和室内人工接虫后种群变化,并对草莓叶片的形态学和生理学特性与抗蚜性的关系进行了分析。结果表明章姬对蚜虫高感,丰香感,卡姆罗莎和吐德拉抗,弗吉尼亚高抗。草莓品种对蚜虫抗性与叶片背面的茸毛密度成正相关,与气孔密度呈显著负相关;与叶片的木质素含量成正比;与酚类物质含量无显著关系,与总游离氨基酸、可溶性固形物含量和水分含量无明显的线性关系。但草莓对蚜虫的抗性程度与叶片中脯氨酸、缬氨酸和胱氨酸的含量有关,特别是缬氨酸和胱氨酸在感蚜品种中的含量是抗蚜品种中的2~3倍。  相似文献   

5.
AIM:To establish and evaluate a hyperbilirubinemia and kernicterus model in neonatal SD rats. METHODS:Three-day-old SD rats were randomly divided to 7 experimental groups by litter and body weight, and were intraperitoneally injected with physiological saline (control group), and 6.25 μg/g (T1), 12.5 μg/g (T2), 25 μg/g (T3), 50 μg/g (T4), 100 μg/g (T5) and 200 μg/g (T6) bilirubin, respectively, twice every day for 3 d. All rats were photographed, weighed and killed 12 h after the last injection. The contents of the stomach were drawn and weighed, and the index was calculated. The liver/body weight ratio was determined, the total and unconjugated bilirubin in the serum and total bilirubin in the brain were calculated, and the contents of ATP and water in the brain were measured. HE and Nissl staining were used to observe the pathological changes. RESULTS:Along with the increase in bilirubin, gradual exacerbation of the general performance of the rats, and yellowish discoloration of the skin and mucous membranes were observed.The degree of the activity gradually reduced, and the weight gain was suppressed. The weight of T6 group showed negative growth, and the 72 h mortality rate was close to 100%. The mortality rate in T4 and T5 groups continued to rise 1 week after injection. Compared with control group, the weight of stomach contents and stomach content index in T3~T5 groups significantly decreased (P<0.01). The liver/body weight ratio in T5 group was significantly higher (P<0.05). The concentrations of serum total and unconjugated bilirubin and brain bilirubin levels in T1~T5 groups were gradually increased, while the brain water content had no difference among groups. The brain ATP content in T1~T5 groups increased at the beginning and reached its peak in T3 group, but compared with control group, that in T4 group and T5 group significantly reduced (P<0.05). HE results showed that, with the increase in bilirubin concentration, the number of the neurons in the cerebral cortex of the rats decreased. In T4 group and T5 group, the neuronal structural disorder, cell swelling, nuclear pyknosis, fragmentation and dissolution, increase in non-homogeneous structure of the material dyed red, and disappearance of nuclear staining were observed. Nissl staining showed that, compared with control group, in T1 group and T2 group, the cortical neurons became smaller, Nissl bodies decreased, and cytoplasmic staining changed little. The cortical neuronal tigroid body color became light gradually, neuron cells become small, and Nissl bodies decreased obviously in T3, T4 and T5 groups. The T4 and T5 rat ce-rebral cortical neurons dissolved or even disappeared. CONCLUSION:Newborn 3-day-old SD rats receiving intraperitoneal injection of bilirubin at doses of 12.5, 25, 50 and 100 μg/g, 2 times a day, can induce hyperbilirubinemia, and 50 and 100 μg/g can cause bilirubin encephalopathy.  相似文献   

6.
苹果果实酚类物质含量与果实苦涩关系的研究   总被引:2,自引:0,他引:2  
乜兰春  孙建设 《园艺学报》2005,32(5):778-782
 以富士苹果为试材, 利用高效液相色谱(HPLC) 研究了果实酚类物质含量与果实苦涩的关系以及酚类物质在果实中的分布。结果表明, 苦涩的幼果中, 根皮素和儿茶素含量均高达成熟果实的30多倍; 表儿茶素、原花青素和绿原酸含量分别为成熟果实的10倍左右。在成熟果实中, 有涩味的果实其绿原酸、儿茶素、表儿茶素和原花青素含量显著高于风味正常的果实; 有苦味的果实其根皮素和原花青素含量显著高于风味正常的果实; 苦涩味均较强的果实其绿原酸、儿茶素、表儿茶素、根皮素和原花青素含量最高。苦痘病果病变组织中根皮素和原花青素含量分别是正常组织的15倍和3倍。绿原酸、儿茶素、表儿茶素和原花青素是引起苹果果实涩感的主要物质; 根皮素、儿茶素和原花青素是引起苦味的主要物质。成熟果实中绿原酸主要分布于种子、果心和果肉; 儿茶素、表儿茶素和槲皮素主要分布于果皮; 原花青素主要分布于果皮中, 果肉和果心中也有分布; 根皮素则主要分布于种子、果皮和果心中。  相似文献   

7.
以大棚重茬草莓土壤为研究对象,以土壤线虫总丰度、群落组成、生物多样性及生态功能特征、土壤养分等为指标,以冗余分析(RDA)为依据,探究棉隆和氯化苦熏蒸对重茬土壤的正、负面影响,旨在为重茬土壤的科学治理提供参考。结果表明,施用棉隆和氯化苦后,土壤中线虫总量与对照相比分别下降83.24%和85.48%;土壤线虫多样性指数H’和成熟度指数MI无显著变化;土壤有机质、速效磷和速效钾含量均显著降低;pH显著升高。RDA分析结果显示,棉隆和氯化苦与小杆属(Rhabditis)、真滑刃属(Aphelenchus)线虫数量及土壤有机质、速效钾和速效磷含量呈显著负相关。该结果揭示了棉隆和氯化苦施用后除能使有害的真滑刃属线虫数量分别显著下降41.47%和29.77%外,也能使有益的小杆属线虫数量显著下降约10%,还能使土壤养分含量大幅度降低,由此表明棉隆和氯化苦在有效控制土壤中有害线虫种群数量的同时,对有益线虫和土壤养分有明显的负作用。综上,棉隆对有害线虫的抑制作用大于氯化苦,同时使食细菌的真头叶属线虫总丰度增加42.03%,因此认为氯化苦的负面影响更大,在生产中应谨慎使用。  相似文献   

8.
采用ITS序列对分离到的菌草食(药)用菌中的真菌性病原菌进行鉴定,并研究其生物学特性。结果表明,从食(药)用菌上分离得到的真菌性病原菌主要包括哈茨木霉(Trichoderma harzianum)、蜡孔菌(Ceriporia lacerata)、赭曲霉(Aspergillus ochraceus)和侧耳木霉(Trichoderma pleuroticola)。分别对4种病原菌进行生物学特性分析,其中哈茨木霉的最适生长温度为29℃,最适pH值为7,能较好地利用葡萄糖、蔗糖、麦芽糖、果糖、甘露糖,以及磷酸氢二胺;蜡孔菌最适生长温度为32℃,最适pH值为6,能较好地利用碳源葡萄糖、蔗糖、麦芽糖、果糖、甘露糖、乳糖,以及氮源酵母膏、牛肉膏和蛋白胨;赭曲霉最适生长温度为26℃,最适pH值为8,能较好地利用碳源蔗糖、麦芽糖、果糖、乳糖、甘露糖,以及氮源酵母膏、牛肉膏和蛋白胨;侧耳木霉最适生长温度为32℃,最适pH值为7,能较好地利用碳源葡萄糖、蔗糖、麦芽糖、果糖、甘露糖,以及氮源磷酸氢二胺。  相似文献   

9.
AIM:To study the electrophysiological effects of lidocaine on the myocardial tissue in guinea-pig left ventricular outflow tract under the conditions of hypoxia, acidosis and treatment with epinephrine. METHODS:The action potentials of pacemaker cells in guinea-pig left ventricular outflow tract were recorded by conventional technique with intracellular microelectrodes. The effects of lidocaine on the spontaneous slow response potentials were investigated under the conditions of hypoxia, acidosis and treatment with epinephrine (EPI). RESULTS:Lidocaine markedly decreased the rate of pacemaker firing (RPF), the velocity of diastolic depolarization (VDD), the maximal rate of depolarization (Vmax), the maximal diastolic potential (MDP) and the amplitude of action potential (APA). Lidocaine also shortened the 50% and 80% of duration of action potential (APD50 and APD80). At the concentrations from 0.1 μmol/L to 10 μmol/L, the effects of lidocaine were more significant. Under the condition of hypoxia and perfusion with deprived glucose content for 15 min, VDD, RPF, Vmax, MDP and APA significantly decreased, and APD50 notably shortened. Under the condition of hypoxia, lidocaine at 1 μmol/L significantly decreased VDD, RPF, Vmax and APA as compared with the cells treated with hypoxia only. Perfusion with pH 6.8 solution for 10 min, VDD, RPF, Vmax and APA significantly decreased, MDP notably increased, and APD50 and APD80 markedly shortened. Under the condition of acidosis for 10 min, lidocaine significantly decreased VDD, RPF and Vmax, and lengthened APD50 and APD80 as compared with the cells under the condition of acidosis alone. Perfusion with EPI at 10 μmol/L for 10 min resulted in significant increases in VDD, RPF, Vmax, MDP and APA, and notable shortenings of APD50 and APD80 were also observed. Compared with 10 μmol/L EPI group, 1 μmol/L lidocaine+10 μmol/L EPI significantly reduced VDD, RPF, MDP and APA, and lengthened APD50 and APD80. CONCLUSION:Lidocaine markedly decreases the autorhythmicity of the pacemaker cells in guinea-pig left ventricular outflow tract and influences the electrophysiological effects of hypoxia, acidosis and EPI.  相似文献   

10.
硅钙对日光温室黄瓜光合作用及产量和品质的影响   总被引:3,自引:0,他引:3  
为了探明硅和钙对黄瓜生长发育的调控机理,以'津优35号'黄瓜(Cucumis sativus L.'Jinyou35')为试材,用盆栽基质培养方法,以不添加硅、钙为对照,研究单施硅(Si)、单施钙(Ca)和硅钙配施(Si+Ca)对黄瓜光合特性、产量及品质的影响。结果表明:Si、Ca和Si+Ca处理均能提高黄瓜叶片的净光合速率(P_n); Si处理的气孔导度(G_s)和蒸腾速率(T_r)显著小于对照,Ca处理显著大于对照,Si+Ca处理与对照差异不显著;Ca和Si+Ca处理可使胞间CO_2浓度(C_i)明显升高,而Si处理与对照差异不显著。与对照相比,Si、Ca和Si+Ca处理Rubisco活化酶(RCA)、果糖-1,6-二磷酸酶(FBPase)、景天庚酮糖-1,7-二磷酸酶(SBPase)、果糖-1,6-二磷酸醛缩酶(FBA)和转酮醇酶(TK)活性显著升高;Si+Ca处理的核酮糖-1,5-二磷酸羧化酶(RuBPCase)活性也明显升高,Si、Ca处理无显著变化。Si、Ca和Si+Ca处理的Rubisco大亚基(rbcL)和小亚基(rbcS)、RCA、FBP、SBP、FBA和TK mRNA相对表达量均显著大于对照。Si、Ca和Si+Ca处理叶片的暗适应下PSⅡ最大光化学效率(F_v/F_m)无显著变化,但光下PSⅡ实际光化学效率(ΦPSⅡ)均明显高于对照。Si、Ca和Si+Ca均可促进黄瓜植株生长,产量分别比对照增加11.75%、14.23%和21.28%,黄瓜果实的可溶性糖、蛋白质、游离氨基酸、维生素C含量显著升高,亚硝酸盐和单宁含量明显降低。可见,Si、Ca和Si+Ca可提高黄瓜叶片的Calvin循环关键酶活性与基因表达,增强光合碳同化能力,提高光化学效率,从而促进植株生长,产量和品质显著提高。3个处理相比,Si+Ca处理的光合能力最强,生长量最大,提质增产效果最佳。  相似文献   

11.
张治科  苗芳芳  吴小梅 《蔬菜》2023,(12):32-38
摘要:为高效防治西花蓟马,针对西花蓟马对不同寄主蔬菜及其不同部位叶片的选择性开展了系统的试验研究,其中采用组织培养法和笼罩法分别研究了西花蓟马对不同寄主蔬菜(黄瓜、辣椒、茄子、豇豆、番茄、芹菜、甘蓝)及其不同部位叶片的选择性。结果表明:在非选择性试验组,在番茄、黄瓜、甘蓝、豇豆上成虫着虫数均以中部叶片最多,分别为14.33、10.33、10.80头和10.00头;在辣椒、芹菜和茄子上若虫孵化数均以中部叶片相对最多,分别为0.33、0.20头和1.80头。在选择性试验组,番茄、芹菜、黄瓜、茄子上成虫着虫数均以上部叶片最多,分别为6.20、2.40、10.00头和4.40头;在甘蓝、茄子、黄瓜和豇豆上若虫孵化数均以中部叶片最多,分别为8.40、4.00、1.80头和1.20头。在组织培养法探究中,黄瓜上成虫着虫数最多(17.17头),茄子次之(4.17头),芹菜(2.00头)、甘蓝(2.00头)、辣椒(1.83头)和番茄(1.83头)上相对较少;若虫孵化数量以茄子(33.67头)上最多,黄瓜、甘蓝、番茄 次之,芹菜和辣椒上相对最少。在笼罩法探究中,成虫着虫数由多到少顺序依次为茄子(4.28头)>黄瓜(4.25头)>番茄(2.12头)>甘蓝(1.72头)>辣椒(1.35头)>芹菜(0.78头),若虫孵化数由多到少顺序依次为茄子(33.67头)>黄瓜(14.50头)>番茄(0.83头),而辣椒、甘蓝、芹菜上没有若虫孵化。综合研究表明,西花蓟马成虫和若虫对黄瓜和茄子具有更强的偏好,其次是番茄、甘蓝、辣椒和芹菜,且西花蓟马优先选择在寄主蔬菜上部和中部叶片取食并产卵。  相似文献   

12.
近年来我国猕猴桃产业发展迅速,产业发展潜力很大,但由于起步较晚、主导品种不明确、管理技术体系落后、质量标准体系不完善等原因,仍然存在诸多问题。主要问题包括(:1)尽管采收面积和产量均位居世界第一位,但单位面积产量低,而且生产总量占水果总量的比例仍然很小(;2)果实品质较差,进口单价始终高于出口单价,进出口贸易逆差明显。笔者通过对国内外猕猴桃生产、贸易数据的统计分析和产业调研,总结产业发展现状,梳理出我国猕猴桃产业存在的主要问题,并分析产生的原因,为促进我国猕猴桃产业健康发展提出对策及建议。  相似文献   

13.
在山东省蓬莱市瑞枫·奥塞斯葡萄基地检测了连续7年清耕、使用除草剂、自然生草、种植狗牙草和种植高羊茅对土壤理化性状和细菌群落的影响。结果表明:相比于清耕,其他4种土壤管理模式均降低了土壤容重,以种植高羊茅最为明显;除种植狗牙草显著提高土壤p H值外,其他3种土壤管理模式对土壤p H值无显著性影响;其他4种土壤管理模式均降低了土壤电导率,以自然生草最明显,降幅达48.1%;生草不同程度地提高了土壤氮磷钾和有机质含量,使用除草剂对氮磷钾含量无显著影响,而使有机质含量降低了39.6%。与清耕相比,生草和使用除草剂均增加了土壤微生物数量和群落多样性,以种植狗牙草的土壤细菌OTU数量和多样性最高;生草提高了土壤有益菌丰度,降低了有害菌丰度,总体上看以种植狗牙草效果最为突出;使用除草剂显著降低了大多数有益菌丰度。对土壤最主要的30个细菌菌落而言,不同土壤管理模式对其产生了不同影响,高羊茅和除草剂对微生物菌属的影响最接近,狗牙草对微生物菌属的影响与其他2种草差异较大。总之,生草模式优于清耕和使用除草剂,不同草种各具优势。  相似文献   

14.
AIM: To investigate the changes of short-chain acyl-CoA dehydrogenase (SCAD) in hypertensive vascular remodeling and to explore the relationship between SCAD and vascular remodeling in hypertension.METHODS: The spontaneously hypertensive rats (SHR; 24 weeks old) and Wistar rats (24 weeks old) were used as experimental control groups. The SHR and Wistar rats of 16 weeks old were trained by swimming as experimental groups. The systolic pressure was measured periodically. The thickness of vascular wall and the diameter of the vascular lumen were measured. The contents of ROS and ATP, the enzyme activity of SCAD, and the expression of SCAD at mRNA and protein levels in the aorta were determined. The free fatty acid in the serum and aorta was also measured.RESULTS: Compared with Wistar group, the diameter of vascular lumen decreased in SHR group. The thickness of vascular wall, the ratio of vascular wall and the diameter of vascular lumen, and the blood pressure in SHR group were increased significantly (P<0.05). Compared with SHR group, the diameter of vascular lumen increased in SHR+swim group. The thickness of vascular wall, the ratio of vascular wall and the diameter of vascular lumen, and the blood pressure in SHR+swim group were decreased significantly. Compared with control group, the expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD, and the content of ATP were decreased in SHR group. However, the free fatty acid in the serum and aorta, and the content of ROS in the aorta were increased in SHR group. The expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD, the content of ATP were increased in Wistar+swim group and SHR+swim group. However, the free fatty acid in serum and aorta, and the content of ROS in the aorta were decreased in Wistar+swim group and SHR+swim group.CONCLUSION: Decrease in SCAD expression may be associated with hypertensive vascular remodeling. Swimming training can reverse hypertensive vascular remodeling by increasing the expression of SCAD in the aorta.  相似文献   

15.
为比较茉莉酸类和水杨酸类激发子外源诱导的茶树挥发物,选用茉莉酸(JA)、茉莉酸甲酯(MeJA)、水杨酸(SA)、水杨酸甲酯(MeSA)等4种激发子喷施茶树,用动态顶空法和气相色谱质谱联用仪收集分析茶树挥发物。4种激发子均可提高茶树挥发物组分数及总量。对照茶树仅释放2种物质,总量低于0.01 ng ? h-1 ? g-1;JA可诱导新释放9种物质,总量可达4.37 ng ? h-1 ? g-1,80%以上为(E)–β–罗勒烯、(E)–4,8–二甲基–1,3,7壬三烯(DMNT)、苯乙醛等萜类及芳香族化合物;MeJA可诱导新释放27种物质,总量可达95.41 ng ? h-1 ? g-1,80%以上为(E)–β–罗勒烯、DMNT、(E,E)–α–法尼烯等萜类化合物;SA可诱导新释放苯甲醚、苯酚、MeSA等3种芳香族化合物,总量可达191.21 ng ? h-1 ? g-1,90%以上为MeSA;MeSA仅诱导新释放MeSA,总量可达507.5 ng ? h-1 ? g-1。激发子浓度提高,茶树挥发物中主要组分释放量或组分数增加。主成分分析与层次聚类分析显示,4种激发子诱导的茶树挥发物得分数差异显著,但JA与MeJA、SA与MeSA诱导的茶树挥发物各聚为一类。综上,JA、MeJA、SA、MeSA等4种激发子均可显著增加茶树挥发物释放,茉莉酸类与水杨酸类激发子诱导的茶树挥发物差异大,而同类激发子诱导的茶树挥发物相似。本研究结果对进一步揭示茉莉酸类和水杨酸类激发子诱导茶树挥发物的生理机制及抗虫功能具有重要意义。  相似文献   

16.
 为了探索不同形态及配比的氮肥对铁核桃(Juglans sigillata Dode.)根际生态因子的影响, 为施肥提供科学依据,采用土壤盆栽试验方法,以铵态氮(NH4 +-N)、硝态氮(NO3 --N)和酰胺态氮[CO(NH2)2] 为氮源,研究氮肥形态及配比对实生苗生长和根际土壤中低分子量有机酸含量、微生物数量及多种酶活 性的影响。结果表明:混施等比例NH4 +-N 和NO3 --N 的实生苗株高、基径、植株的鲜质量及地上部和根 系的鲜质量都最大(P < 0.05),分别为58.03 cm、18.21 mm、238.19 g、147.68 g 和90.51 g,根际土壤中 有机酸总量和细菌、真菌、放线菌的数量及微生物多样性指数显著高于其它处理,分别为16.72 μg · g-1 FW、 592.00 × 105 CFU · g-1、34.33 × 104 CFU · g-1、19.33 × 105 CFU · g-1 和0.1738;酸性磷酸酶、中性磷酸酶、 碱性磷酸酶、蔗糖酶和淀粉酶的活性最强(P < 0.05),分别为9.54、0.24、3.60、61.98 和8.03 mg · g-1。 单一施CO(NH2)2、NO3 --N、NH4 +-N 会降低根际土壤中有机酸含量、微生物数量和微生物多样性指数。在 混施NH4 +-N 和NO3 --N 的情况下增加NO3 --N 比例会明显降低根际土壤蛋白酶活性。根际土壤中细菌、真 菌和放线菌的数量与中性磷酸酶、碱性磷酸酶、硝酸还原酶、蔗糖酶和淀粉酶活性呈显著或极显著正相 关;细菌数量与酸性磷酸酶活性呈显著正相关;有机酸总量与脲酶、中性磷酸酶、碱性磷酸酶、硝酸还 原酶、蔗糖酶和淀粉酶的活性及微生物数量呈显著或极显著正相关;微生物数量及有机酸总量与过氧化 氢酶呈极显著负相关。混施等比例的NH4 +-N 和NO3 --N 能够改善铁核桃根际生态环境,促进实生苗的生 长。  相似文献   

17.
刘志强  洪亘伟 《北方园艺》2012,(14):101-104
快速发展的我国园林绿化行业亟需科学的评价。20世纪80年代以来,我国园林绿化评价的研究呈现出不断增加的趋势,并成为风景园林学科研究领域的重点和热点问题。通过阐述国内园林绿化评价的研究进展,提出了园林绿化评价的概念、分类、意义和基本程序,归纳我国园林绿化评价的研究历程;总结园林植物评价、园林效益评价、园林绿化总体布局与结构评价的研究动态,剖析了研究的不足,并在此基础上提出了我国园林绿化评价研究的建议及展望,以期为推动我国园林绿化评价的研究及发展提供参考和借鉴。  相似文献   

18.
AIM: To investigate the effects of monopolar electrocoagulation on the changes of electrolytes and uterine ultrastructure in the patients with laparoscopically hysterectomy.METHODS: Sixty patients, who accepted laparoscopically hysterectomy in the Third Affiliated Hospital of Jinan University from December 2009 to December 2010,were selected in the study and divided into 2 groups by the different hemostasis methods.Thirty patients were in monopolar electrocoagulation group and another 30 patients were in Ligasure group.the plasma concentrations of electrolytes (potassium, sodium, chlorine and calcium) were measured before operation, during operation, 24 h and 48 h after operation.The uteruses from 5 patients in each group were collected and the dissections between uterine horn and fallopian tube were prepared for observations under light microscope and transmission electron microscope.RESULTS: Compared to the levels before operation, the concentrations of plasm potassium in all patients were increased during operation,and the plasm sodium was not changed due to the supplement during and after operation, but the plasm chlorine and calcium were decreased.The electrolyte levels came to normal 24 h and 48 h after operation.Comparing the difference between 2 groups, no statistical significance of electrolyte concentrations was observed.Under transmission electron microscope, breakage of the cell membrane, expansion of mitochondria, pyknosis of chromation and karyorrhexis were also observed.CONCLUSION: The pathological changes exist under transmission electron microscope, although no change of the tissues in the place 10 mm far away from monopolar electrocoagulation is found under light microscope.  相似文献   

19.
自由基清除剂对延缓青花菜花蕾衰老的效应   总被引:18,自引:2,他引:18  
叶陈亮  柯玉琴 《园艺学报》1996,23(3):259-263
青花菜采后花蕾迅速衰老,叶绿素和蛋白质含量明显下降,超氧物歧化酶(SOD)和过氧化氢酶(CAT)活性随衰老进程先升高而后下降,丙二醛(MDA)持续增加,细胞膜透性迅速增大。20mg/L6-苄基腺嘌呤(6-BA)处理明显延缓叶绿素和蛋白质的降解,提高SOD活性,对CAT激活尤为明显,抑制了Haber-Weiss反应,降低过氧化氢(H2O2)和羟基自由基(OH)含量,延缓膜脂过氧化作用,降低子MDA含量,减小膜渗漏,延缓花蕾衰老。20mg/L6-BA中加入02%苯甲酸钠(SBN),对6-BA产生的各种延衰效应均有增效作用,进一步推迟花蕾衰老。200mg/L抗坏血酸(AsA)促进叶绿素和蛋白质降解,在提高SOD和CAT活性的同时,MDA反而明显增加,膜透性迅速增大,加速衰老。  相似文献   

20.
AIM: To study the effects of Tongxinluo on the activation of platelets in a rabbit model of atherosclerosis. METHODS: New Zealand rabbits were randomly divided into 7 groups: normal group, model group, the groups treated with high, medium and low doses of Tongxinluo micropowder (0.15, 0.3 and 0.6 g·kg-1·d-1), atorvastatin group (2.5 mg·kg-1·d-1), and aspirin group (12.5 mg·kg-1·d-1). The rabbits in normal group was fed with common diet for 12 weeks, and the rabbits in model group were fed with high-fat diet for 12 weeks to establish atherosclerosis model. The rabbits in the rest groups were treated with the corresponding drugs, at the same time to give high-fat diet. Fasting for 12 h after the last treatment, whole blood was collected to perform the blood routine test, and to measure serum and plasma levels of lipids, platelet factor 4 (PF4) and soluble CD62P (sCD62P). Flow cytometry was used to analyze platelet calcium ion concentration. Electron microscopy was used for platelet superfine observations, and light microscopy for observing the pathological changes. RESULTS: Compared with normal group, the levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), platelet counts, and mean platelet volume in model group were significantly elevated, and the levels of PF4, sCD62P and calcium were also significantly increased (P < 0.05). Compared with model group, except aspirin group, the levels of TG, TC and LDL-C in high, medium and low doses of Tongxinluo groups and atorvastatin group were effectively decreased. The platelet counts and mean platelet volume in all treatment groups were markedly decreased, and the serum levels of PF4, sCD62P and Ca2+ in platelet (P < 0.05) were reduced. In electron microscopic observation, the shape of platelet was regular and organelles distributed uniform in normal group. However, in model group, the shape of platelet was irregular, pseudopodia forming was obviously observed, and α particles and dense granules decreased, indicating that the platelet was activated. To a different extent, the platelet shape, increase in the number of α particles and dense granules were improved in treatment groups and the damage of the cytoplasm was attenuated. Through histopathological observation, the intimal was smooth and complete in normal group. In the model group, the intimal thickness markedly increased, foam cell aggregated, and plaque was formed. Compared with model group, the intimal thickening and the number of foam cells were significantly decreased, and plaque formation was not obvious in atorvastatin group and high dose of Tongxinluo group. The pathological damages in the other treatment groups were alleviated in different degrees. CONCLUSION: Tongxinluo significantly inhibits the activation of platelets in the process of atherosclerosis, and has important clinical value to delay the atherosclerotic thrombosis.  相似文献   

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