平菇早秋种植“十注意”

平菇种植通常是冬季节种植(10月中旬-12月下旬,不超过元月底种植的平菇),主要供应冬季、春季市场,为了延长平菇供应季节、提高平菇种植效益,我们正在推广平菇早秋种植(7月底-9月下旬、不超过10月初种植的平菇)。平菇早秋种植与传统冬季种植相比具有显著优点:一是主要供应秋季、冬季市场,市场平菇商品少、市场价格高,种植效益突出,二是种植出菇季节温度合适,温度、湿度管理相对简单,三是种植周期短、用工成本低;但是早秋平菇种植也具有较大风险性,一是种植季节温度高,种植污染率高,增加种植难度,二是容易滋生病虫害,增加管理难度,因此要做好早秋平菇种植,必须按照"三选用、四注意、三加强"搞好十个方面的平菇早秋种植管理。     

两种不同种植方式对龙葵叶片虫食状的影响研究

昆虫与植被之间相互关系的深入研究,有助于更好的理解生态系统结构与功能之间的关系以及生态系统生物多样性维持机理。本文通过对集中种植和分块种植下两种不同种植方式龙葵叶片虫食状进行调查分析,以期对龙葵的栽培和养护提供理论基础和技术建议。研究结果表明:龙葵叶片中共识别出11种虫食状类型,其中,集中种植方式有10种,分块种植方式有11种,各种虫食状类型出现频率在0.4%-24.7%;集中种植样地的龙葵叶片虫食状种类数、Shannon-Wiener指数和Pielou均匀度指数均低于分块种植;分块种植的龙葵叶片受到植食性昆虫的伤害频率较高,但是集中种植的龙葵叶片受到的伤害程度却明显高于分块种植方式。因此,种植龙葵应尽量避免大规模集中种植方式,不同生态系统边界之间边缘效应的尺度和强弱的关系是未来研究的重点和核心问题。     

转基因(Cry1Ac)抗虫棉对土壤微生物的影响

对不同种植年限的转基因(Cry1Ac)抗虫棉田土壤中主要微生物数量变化进行了测定,结果表明：（1）种植转基因抗虫棉后对土壤微生物细菌、放线菌和真菌数量的影响趋势基本相似;（2）种植抗虫棉1年后,土壤中细菌、放线菌、真菌数量将有所增加,连续4年达到高峰,然后数量开始下降,连续种植7年后,棉田微生物数量接近于种植1年的棉田;（3）种植1年后又种植非转基因棉花的棉田,土壤微生物数量低于种植1年抗虫棉的棉田,与种植非转基因棉的数量无明显差异。由此可见,种植转基因抗虫棉对土壤微生物数量有一定的影响。     

2005年转基因作物商业化生产全球态势

2005年是转基因作物商业化种植的第十个年头。该年全球有21个国家的850万农民种植了4亿公顷转基因作物。自1996年生物技术作物首次商业性种植以来,10年间其种植面积每年都以两位数的速度增长,参与种植的国家从6个增至21个。转基因作物的全球种植面积增加了50多倍。转基因作物种植面积的迅速增加反映出农民对农业生物技术的信任和信心。根据农业生物技术应用国际组织(isaaa)的调查,2005年,经核准的转基因作物全球种植面积为9 000万公顷,比2004年的8 100万公顷增加了11%。与2004年相比,2005是具有里程碑意义的一年,新增首次商业化种植转基因作…     

论花坛种植施工及草花养护技术

花坛成品草花的种植和养护,是维护花坛草花种植工程建设的重要环节,本文主要对园林绿化工程中花坛种植施工及草花种植养护进行了论述。     

旋转加压种植法在新型生物人工复合血管体外内皮化过程中的实验研究

目的：探讨在新型生物人工复合血管内腔面联合种植平滑肌细胞和内皮细胞的方法,比较研究旋转加压种植与普通灌注种植两种方法的内皮化效果,方法：先制备新型生物人工复合血管及获取培养鉴定平滑肌细胞和内皮细胞,再和旋转加压种植与普通灌注种植两种方法将平滑肌细胞和内皮细胞培养种植于新型复合血管内腔面,以光镜及扫描电镜等观察评价内皮化的效果。结果：旋转加压种植2小时末的复合血管腔内有大量内皮细胞,旋转加压种植9天后已形成完整的内皮细胞单层;普通灌注种植的复合血管内腔有内皮细胞附着,分布不均匀,未形成完整的内皮细胞层,结论：以旋转加压种植法在新型复合血管内腔面联合种植平滑肌细胞和内皮细胞效果满意,基本实现内皮化,可以满足复合血管内皮化的要求。     

ISAAA 2013年最新发布

<正>2013年是转基因作物成功商业化的第18年:种植面积比2012年上升500万公顷或3%,从1996年的170万公顷增加到2013年的1.75亿公顷。全球27个国家1 800万农民选择种植转基因作物,其中19个为发展中国家,美国种植面积达到7 010万公顷,占全球种植面积的40%。巴西连续五年成为转基因作物第二大种植国,相比2012年,其转基因作物种植面积增加370万公顷,增幅达10%,种植面积超越     

探究北方大豆种植技术

本文主要阐述了大豆的种植技术要点,主要包括:大豆生产的价值,大豆产量质量的影响因素,北方大豆种植技术等。目的是探讨大豆种植技术,从而科学有效的种植大豆,使北方大豆高产、优产。     

ISAAA信息

<正>2014年是转基因作物商业化的第19年,转基因作物种植面积持续增加。28个国家(20个发展中国家,8个发达国家)的1 800万农民种植了1.81亿公顷(4.48亿英亩)的转基因作物,比2013年27个国家的1.75亿公顷有所增长。中国转基因作物种植面积世界排名第6位,种植面积为390万公顷,种植的转基因作物包括棉花、木瓜、白杨、番茄、甜椒。孟加拉国是种植转基因作物的新成员。2013年10月,孟加拉国首次批准了Bt茄子的种植,小农户们于     

辽东山区林权制度改革中林下种植模式对林下植物物种多样性的影响

以样方调查数据为基础,采用物种丰富度指数、均匀度指数和多样性指数,对辽宁省东部山区森林生态系统中种植林下参和大叶芹这两种作物对林下植物物种多样性的影响进行了研究,并分析了不同作物种植样地和未种植样地以及不同种植作物样地之间的各种指数的差异程度。结果表明:(1)种植两种作物均对灌木层物种产生了显著的影响,降低了物种多样性。(2)种植林下参使得草本层的物种丰富度显著降低,均匀度显著增加,而多样性指数差异不显著。(3)种植大叶芹使得草本层的物种丰富度、均匀度和多样性指数均显著降低。(4)林下参种植样地和大叶芹种植样地之间草本层的物种丰富度指数、均匀度指数和多样性指数之间存在显著差异。     

THE TWO KINDS OF DEATH OF WILLIAM HARVEY

The determining factors in congestive heart failure as well as in shock are more often extracardiac than in the heart itself. Carbon dioxide tension in the blood is as important as the oxygen tension. Carbon dioxide is a hemodynamic agent of the first magnitude. It can be quickly increased or decreased by altering the ventilation of the lungs. It is a prime factor in determining whether the circulation fails from a lack or from suffocation by an excess.     

THE CHARACTERISTICS OF ULTRAFILTRATES OF PLASMA

1. Calculations from the Fick diffusion law are shown to predict that membrane equilibria should be established during the course of ultrafiltration. 2. It is shown that the chloride ion is more concentrated and the sodium ion less concentrated in the ultrafiltrate than in the plasma from which the ultrafiltrate was derived. 3. It has been found that by increasing the base bound by protein through a reduction in the bicarbonate content the difference between the plasma concentration and the ultrafiltrate concentration for the several ions studied increases. 4. Calculations from the Donnan equation as to the magnitude of the change in base bound by protein at differing hydrogen ion concentrations are in substantial agreement with the observed values, thus rendering it probable that the membrane equilibrium effect is responsible for the change in distribution ratios observed. 5. It is pointed out that the observed difference in the distribution ratio of cations from that of the chloride anion is probably to be explained by the influence of protein in lowering the activity coefficient of cations when on the alkaline side of the isoelectric point. 6. It is pointed out that account must be taken of these observations in any consideration of the rôle of ultrafiltration in the production of any secretion or body fluid.     

现代中国人体质特征及其类型的分析

文章运用多元分析方法,分析了十六个地区的汉族和廿五个少数民族的体质特征,提出现代中国人的体质特征明显分为两大地区类型,即长江以北的为北部类型和长江以南的为南部类型。并且认为两大类型体征的形成始于我国文化发达的新石器时代.     

柳江化石智人的身高

作者将柳江人的右侧股骨残段作了复原。根据华南人由肢骨测量身高的公式,如果柳江人股骨属男性,其身高为156.69±3.74厘米,比现代当地居民的平均身高偏矮。     

FURTHER EXPERIMENTS ON THE ABSORPTION OF IONS BY PLANTS,INCLUDING OBSERVATIONS ON THE EFFECT OF LIGHT

1. The conditions of illumination were found to exert a very significant influence on absorption of ions from dilute solution by Nitella. These conditions were also found to influence the penetration of Br and NO₃ into the cell sap. 2. It is concluded that absorption of ions by plants from dilute solutions involves energy exchanges, with light as the ultimate source of the energy. It is suggested that the absorption is intimately related to growth and metabolism. 3. One ion may affect the removal from solution or penetration into the cell sap of another ion present in the same solution, even in solutions of extremely low concentration. It is probable that all three types of relations may exist—anion to anion, cation to cation, and anion to cation. 4. The sulfate and phosphate ions exerted far less influence on the absorption of nitrate than did chlorine and bromine ions. It is suggested as a possibility that sulfate does not penetrate readily to those surfaces at which chlorine, bromine, nitrate, and other ions may become effective.     

中国寒武纪双壳类研究之评述

长期以来,双壳类研究者虽未将扬于蛤(Yangtzedonta Yu)纳入到双壳类早期系统演化的研究范畴,支却又难以予以完全否定。最近,钱逸的工作终于解决了这一悬案,这是寒武纪带壳软体动物研究的一项重要进展。然而,钱逸对双壳类早期演化的理解仍存在着误解,例如,将Xianfengoconcha Zhang当作是“最古老的双壳类”,为此有必要对近二十年来我国寒武纪双壳类的研究进行回顾与总结。Xianfengoconcha发育有两侧对称排列的所谓“片状齿”,实属腕足类小圆货贝型铰合构造。化石证据表明,真正的片状齿是由古栉齿型铰齿演化而来,因此,古异齿型不是双壳类最古老的铰齿类型。目前,我国没有争议的寒武纪双壳类只有．Pojetaia Jell一属。     

SOME PROPERTIES OF PROTOPLASMIC GELS : I. TENSION IN THE CHLOROPLAST OF SPIROGYRA

The chloroplast of Spirogyra is a long, spirally coiled ribbon which may contract to form a short, nearly straight rod. This happens under natural conditions and it can also be produced by a variety of inorganic salts and by some organic substances. It also occurs when the chloroplast is freed by centrifugal force from the clear peripheral protoplasm which is in contact with the cellulose wall. It would therefore seem that the chloroplast may be passively stretched by the action of the clear protoplasm and hence it contracts as soon as it is set free. This contraction happens in dead as well as in living cells. It would be of much interest to know how the protoplasm brings about the coiling of the chloroplast and how the chloroplast is set free by various reagents. Presumably they must penetrate the living protoplasm to produce the effects described. In one species partial contraction without detachment from the peripheral protoplasm can be brought about by lead acetate. This is reversible. Lead nitrate does not produce this result. The attack upon the problem is greatly facilitated by the study of dead cells. Thereby we reduce the number of variables but the chloroplast continues to react to certain chemical and physical agents in much the same manner as in the living cell and the solution surrounding it can be controlled as is not possible in the living cell. We must await further investigation to learn what plant and animal cells contain gels under tension and what functions they perform.     

关于百色手斧问题——兼论手斧的划分标准

本文从讨论手斧的定义出发 ,归纳出划分手斧的标准 ,并以此来衡量百色手斧 ,认为百色手斧是真正手斧。由于百色手斧的原料 (多为石英岩 )质地粗糙、结构面多、且有的在制作工具时已被风化 ,这在很大程度上影响手斧的制作质量 ,因此 ,百色手斧更多地显示出早期类型手斧的特点。百色手斧和印度、中东以及非洲的部分手斧有许多相同之处。这些相同之处主要是由于原料相同或相近的结果。文中论述的百色手斧 ,部分尚属首次报道。     

PARTIAL CHARACTERIZATION OF A NEW MYELIN PROTEIN COMPONENT

A new protein component has been demonstrated in myelin isolated from rat whole brain and from white matter dissected from bovine, dog and rabbit brain. It is also present in rabbit optic nerve. It does not appear to be present in other subcellular fractions of rat brain. It has a molecular weight of 20,540 ± 490(S.D.), as determined by polyacrylamide gel electrophoresis in sodium dodecyl sulphate. A rapid procedure for the isolation of myelin is also described.     

鲫鱼酸性磷酸酶酶学特性及不同效应物对酶活力的影响

经NaAc-HAc缓冲液(pH5.0)抽提,正丁醇处理,硫酸铵分级沉淀,DEAE-32离子交换层析,SephadexG-150凝胶过滤纯化,从鲫鱼内脏中分离纯化出电泳纯的酸性磷酸酶。该酶提纯倍数为30.82,比活力195.06U/mg。研究表明,该酶催化对硝基苯磷酸二钠水解反应,最适pH4.8,pH小于4和大于7时不稳定;最适温度45℃,温度高于50℃不稳定;米氏常数为0.23mmol/L,利用SDS-PAGE测定酶亚基分子量为33.3kD。化学修饰剂SUAN、PMSF、DTT、NBS对该酶活力影响不大,BrAc和IAc有明显抑制作用。金属离子对该酶催化活力有不同影响,Na+、K+、Ni2+、Co2+影响不显著,Mg2+、Ca2+、Ba2+、Mn2+有激活作用,Ag+、Cu2+、Pb2+、Cd2+有抑制作用,其中Mg2+、Ca2+、Pb2+、Cd2+对鲫鱼酸性磷酸酶荧光光谱的影响表明金属离子对酶活力的影响与酶构象改变有关。