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1.
PTEN is a candidate tumor suppressor which has sequence homology withdual-specifici-ty phosphatase. PTEN is a multifunctional protein endowed with a phosphatase activity capable of dephosphory-lating both tyrosine phosphate, serine/threonine phosphate residues on proteins and phospholipids of the phosphati dylinositol pathway. PTEN appears to be mutated at considerable frequency in several types of humantumors, including those frombrain, breast, endometrium, and prostate. PTEN play an important role in pathogenesis of tumor, tumor cell invasion and metastasis. In this review, we will discuss the chemical structure of PTEN, its phosphatase activity, the ability of affecting signal transduction, and its mutational status in cancer.  相似文献   

2.
1、贮藏期病害及发生规律 1.1真菌病害已有的研究表明,贮藏期危害葡萄的病菌全部为真菌.细菌的生长因葡萄浆果的pH值在2.9-4.0的范围内而被限制.低温贮运过程中危害葡萄的病原菌包括:灰霉(Bolty cinera Pers)、青霉(Penicillia spp.)、交链孢霉(Allernaria spp.)、芽枝霉(Clad ospriumSp.)和匐梗霉(Stemphy lium Sp.)等.葡萄常温贮运过程中致病菌主要有根霉(Rhizopusstolorifer(Ehrenb.:Fr.)Vuill).  相似文献   

3.
通过病防工作实践,感到城市绿地植物病虫害的预防和防治要从植物品种选择、配置、适地适树、加强养护、提高植物自身抗性和健全检疫机制等方面做起,提高全民的环保意识,为减少污染,保护环境共同努力。  相似文献   

4.
祖凌 《现代园艺》2011,(11):130-131
阐述了现代园林的基础知识,并通过对园林绿化生态效益的分析,概括了现代园林绿化的新概念及在城镇规划中的作用,并浅析如何在城镇中进行现代生态园林绿化的应用。  相似文献   

5.
时下,在蔬菜生产上,人们为了追求高产,大量施用氮、磷、钾化肥,而忽视了微量元素的应用,特别是保护地土壤中大量元素与中微量元素不平衡的矛盾日益突出.2005年9月,笔者对招远市二十个蔬菜生产重点村的三十二个日光温室(每个660m2)及十个露地菜田进行了土壤检测,结果表明:菜田土壤均属强酸性,pH平均为4.8.土壤水溶性硼含量平均为0.23mg/kg,比中等肥力菜田土壤硼的最低界限值0.5mg/kg,尚差0.27mg/kg,呈极缺状态;土壤有效锌含量平均为1.5mg/kg,与高产田有效锌要求3mg/kg,尚差一半;土壤中钼的含量仅有0.10mg/kg,比要求的最低临界值0.15mg/kg,尚差0.05mg/kg.由于微量元素的缺乏,导致蔬菜生理病害日益严重,如:缺锌引起的小叶病;缺硼引起的果实木栓化;缺钙引起的番茄、辣椒脐腐病等大量发生.据2004年招远市郭家埠菜田调查,青椒脐腐病病株率达到30%以上,高的地块达到50%,给生产造成了很大损失.因此,蔬菜缺素症应当引起专业技术人员及广大菜农的重视.笔者根据多年来的试验研究,总结出了一套蔬菜缺素症的综合防治技术,现介绍如下.  相似文献   

6.
国家蔬菜工程技术研究中心共收集苋菜及部分野生蔬菜资源1070份。按食用器官分类,共分为七大类数十个种类,显示出我国蔬菜遗传资源的多样性。分析测定了703份野生蔬菜的营养成分。针对目前我国在野生蔬菜资源的基础研究和开发利用中存在的问题,提出了相应的对策。  相似文献   

7.
在乙醇:龙眼果皮= 100∶4(v/w )、70 ℃、100 m in 的最佳条件下,pH 4.52,λRmax= 370 nm ,呈鲜黄色。龙眼黄色素(R)乙醇提取液的pH、光、热、离子、共存物对R的稳定性有不同的影响。综合考虑各种影响因素,用A、B、C保鲜剂、浸果3 m in 后,分别于室温、15、- 10 ℃下贮藏10、30、60d,龙眼的好果率为87 % 、95 % 、100 % ,损耗率为14 % ~0,基本保持果壳原色和果肉的色泽、风味、品质,取得了护色保鲜的效果  相似文献   

8.
以鲜菌草(巨菌草、象草、五节芒)及其相对应的干菌草为试材,采用单因素试验方法,研究鲜菌草与干菌草灭菌前与灭菌后的碳氮含量及碳氮比的变化。结果表明:灭菌前,鲜菌草的碳含量低于相应干菌草的碳含量,鲜菌草的氮含量高于相应干菌草的氮含量,鲜菌草的碳氮比均低于相应干菌草的碳氮比;灭菌后,鲜菌草与干菌草的碳含量和氮含量均有所降低,除了干巨菌草以外,鲜菌草与干菌草的碳氮比均降低,鲜菌草的碳氮比也低于相应干菌草的碳氮比。因此,灭菌对鲜菌草和干菌草的碳含量、氮含量和碳氮比均有影响,鲜菌草更适合用于栽培较低碳氮比的食药用菌。  相似文献   

9.
早实核桃的生长发育特点与整形修剪   总被引:3,自引:0,他引:3  
目前我国栽培的核桃可分为两大类,一类为结果晚的品种如礼品1号、礼品2号、晋龙1号、秦优1号等;另一类为早实核桃品种(栽后2年结果)如辽宁1号、辽宁3号、辽宁5号、中林1号、鲁光、陕核1号、绿波等。这两类核桃在生长发育上既有相同之处,也有着不同的生理生态特征,因此,在栽培管理上就有所不同。据我们的多年观察研究,就早实核桃的整形修剪谈几点意见。1生长特点早实核桃为乔木,树高可达10m以上,干径粗度可达60cm以上,寿命多为50~80年。早实核桃侧芽萌发力强,易抽生二次枝。树体在幼树阶段管理不当,极易造成树形紊乱,结果部位快速外移,产量…  相似文献   

10.
The early-1990s’ war in former Yugoslavia led to severe damage to the urban and peri-urban forests of Sarajevo, capital of Bosnia and Herzegovina. During the Siege of Sarajevo (April 1992–March 1996), after the energy supplies to the city had been cut off, over three-quarters of all urban trees and nearly all peri-urban trees within the siege line were cut down for firewood by the desperate residents. After the war, the city trees were quickly and effectively replanted, and Sarajevo provides a useful case study of urban forest recovery. This study presents the observations and measurements, of trees that survived the war and the trees planted after the war, made in Sarajevo in May 2008. We summarize the lessons learned from the Sarajevo experience, regarding both damage and replanting, which include the close relationship between the urban tree damage and the specifics of military operations, the importance of the initial planting stock, and the advantages of collaboration between academic researchers and urban forest managers.  相似文献   

11.
AIM: To explore the therapeutic strategies of heat-clearing and detoxifying (HCDT) and Yin-invigorating and fluid-supplementing (YIFS), the method of Chinese medicine, on the high density lipoprotein (HDL) and alkaline phosphatase (ALP) molecules, which are associated with endotoxin-degradation. METHODS: The animal model of endotoxemia was established by the injection of E. Coli lipopolysaccharides through rabbits ear vein. The endotoxemic rabbits were treated respectively with two representative herbal preparations of therapeutic principles against febrile diseases: HCDT or YIFS preparations. The serum levels of interleukin-1 (IL-1), tumor necrosis factor α (TNF-α) and HDL, the ALP activity, the expression of ALP mRNA in liver and kidney tissues were observed. RESULTS: The serum levels of IL-1 and TNF-α in HCDT group were significantly decreased, while the serum ALP activity and the expression of ALP mRNA in liver and kidney tissues were obviously increased, as compared with those in model group. Meanwhile, the serum levels of IL-1 and TNF-α in YIFS group were significantly reduced, and its plasma HDL level was elevated. CONCLUSIONS: Both the herbal preparations, HCDT and YIFS, have the scavenging effects on the overproduction of inflammatory cytokines such as IL-1 and TNF-α induced by endotoxin, but their effects on the endotoxin-degrading molecules might be different. HCDT principally increases ALP activity and enhances ALP expression in liver and kidney tissues, while YIFS might preferably facilitate the elevation of plasma HDL level.  相似文献   

12.
预测预报病虫害的发生发展规律有利于控制和预防苹果病虫害,而开花前后的病虫害防治是后期苹果树保花保果的关键。对苹果树萌芽至花期的病虫害状况,如虫口基数、气候变化等进行调查,预测病虫发生情况,总结苹果生长关键时期,如萌芽期、修剪期、花期前后的病虫害综合防治建议,能够提高苹果的产量和品质,维护苹果产业的可持续发展。  相似文献   

13.
采用田间小区试验,研究了大蒜干物质积累与硒吸收、分配及累积特性规律。结果表明:大蒜从幼苗期到鳞芽花芽分化期干物质累积量随植株生长发育呈快速增长趋势,在鳞芽花芽分化期达到高峰时干物质积累量为15 022.50kg/hm2,后期趋于平衡;大蒜不同器官硒含量在不同生育期均表现为鳞芽花芽分化期>鳞茎膨大期>蒜薹伸长期>幼苗期,大蒜在鳞芽花芽分化期硒累积量骤增,累积量占总硒累积量的57.82%,说明这一段时期是大蒜吸收硒的关键时期;鳞茎膨大期大蒜各器官硒含量积累量大小为鳞茎>茎>叶>根。  相似文献   

14.
The effects of combinations of salinity (no salt, 2000 p.p.m. or 4000 p.p.m. of CaCl2 and NaCl, 1:1) and water table (30 cm, 60 cm or 90 cm from the soil surface), on the vegetative growth and tolerance of ‘Golden Japanese’ plum and ‘Mit Ghamre’ and ‘Balady’ peaches were studied. The plants were grown in lysimeters. The growth of the trunk, total shoot length, the increase in shoot length per cm and the fresh weight of top, root and total plant were reduced with increasing salinity of the irrigation water. The effect was accentuated when the plants were maintained at high water table level. The salinity treatments resulted in the death of 43%, 73% and 76% of the plants in the plum, and the ‘Mit Ghamre’ and ‘Balady’ peaches, respectively, indicating that the plum is more tolerant to salinity than the peach. The plants of the salinity treatments showed various symptoms of salt injury, such as leaf burn, defoliation, shoot die-back and finally death. In the peaches, salt injury started to occur in the first growing-season, whereas the salt injury appeared in the plum in the second growing-season. The symptoms were more pronounced in the 4000 p.p.m. treatment than in the 2000 p.p.m. treatment and were more pronounced at the high water table level. The salinity level was the predominant factor and the effect of the water table on the vegetative growth diminished with increase in the salinity level of the irrigation water.  相似文献   

15.
根据西瓜、棉花两者生长发育特点进行套种试验,研究其高产高效栽培模式。试验示范结果表明,以西瓜行株距4.5m×0.65m,棉花行株距1.5m×0.45m的种植密度,西瓜与棉花之间互颉作用最小,西瓜和棉花的产量和产值在3个套种模式中位居第1,在5个处理中经济效益最高。  相似文献   

16.
1、核桃溃疡病 1.1危害症状溃疡病真菌病害,主要危害核桃树幼树主干、嫩枝和果实,初为褐、黑色近圆形病斑,直径0.1-2cm,多发生在树干及主侧枝基部.有的扩展成菱形或长条形病斑.在幼嫩及光滑的树皮上,病斑呈水渍状或为明显的水泡,破裂后流出褐色粘液,遇空气变黑褐色,随后病部散生许多小黑点,严重时病斑相连呈菱形或长条形.当病部扩大到环绕枝、干一周时,出现枯梢、枯枝或整株死亡.秋季病部表皮破裂.在较老的树皮上,病斑多呈水渍状,中心黑褐色,病部腐烂深达木质部.果实受害后呈大小不等的褐色圆斑,早落、干缩或变黑腐烂.  相似文献   

17.
果蔬加工研究现状及发展前景   总被引:7,自引:0,他引:7  
综述了国内外果蔬加工的新趋势,对果蔬的营养价值和保健功能加以分析,阐述了果蔬加工的发展前景.  相似文献   

18.
杜鹃花常见病虫害及其防治   总被引:1,自引:0,他引:1  
于炜  冯玉 《中国园艺文摘》2012,(11):121-122,174
杜鹃为我国十大传统名花之一,病虫害的发生是影响杜鹃花正常生长的主要原因之一。文章主要阐述了危害杜鹃花的病虫害的形态特征、发生特点及防治方法。  相似文献   

19.
王兵 《山西果树》2022,3(2):55-57
'玉铃铛'枣作为阜阳市的优良林木品种,近几年在栽培技术和生产管理上有了新的突破,果实产量有了显著提高、品质得到显著改善,形成了良好的辐射效应,调动了阜阳市及周边人们种植'玉铃铛'枣的积极性.然而,随着种植面积不断扩大,病虫害的发生也有所上升,直接影响了果实产量、品质和林农收入,甚至造成树木死亡.危害'玉铃铛'枣的主要病...  相似文献   

20.
梨轮纹病又称瘤皮病、粗皮病,是我国南方早熟梨主要病害之一.枝干发病,促使树势早衰,影响幼树生长;此病侵染果实,常造成短期烂果严重,影响外销.早熟梨品种如金水二号、翠冠等易感病,果实快的三天,迟的五、六天即出现小斑点;中、晚熟品种如黄花、湘南感病力次之;晚三吉,今青秋较抗病.品种间抗病力的差异主要与品种皮孔的大小、多少以及组织结构有关.  相似文献   

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