不同冬小麦品种不同叶位叶片在个体产量形成中的作用

以黄土高原南部半湿润区土垫旱耕人为土为供试土壤进行大田试验,在不同施氮水平基础上,以NR 9405、9430、偃师9号、小偃6号、陕229号、西农2208、矮丰3号和商188等8个冬小麦品种为供试材料,研究不同年度、不同农艺性状冬小麦不同叶位叶片在个体产量形成中的作用.结果表明,冬小麦旗叶和倒二叶长度、宽度及其叶面积同时受品种和施氮控制,施氮后显著增加.旗叶和旗叶以下余叶对冬小麦籽粒产量形成起着重要作用.与不去叶处理相比,开花期去旗叶、留旗叶去其余叶、去所有叶对单穗粒数影响不大,各处理粒数变化在32.91~34.95粒/穗之间.但去旗叶后穗粒重有一定程度下降,比对照植株下降8.7%;留旗叶去其余叶和去所有叶处理,分别比对照植株减少18.2%和29.3%;去叶处理对单粒体积的影响与对单穗粒重的影响相一致;去旗叶、留旗叶去其余叶和去所有叶处理单粒重极显著降低,分别比对照下降7.0%、13.3%和25.1%.花后单株叶对产量的贡献大体上在1/4~1/3之间.     

生物淋滤法去除污泥中的重金属

本研究从剩余活性污泥中分离得到两株土著硫杆菌。对两株菌进行了分类鉴定。确立二者分别为嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans, A. f)和嗜酸性氧化硫硫杆菌(Acidithiobacillus thiooxidans, A. t)。将二者的单菌和混合菌分别接种于剩余活性污泥中, 进行了为期9 d的生物淋滤, 对淋滤过程中的pH变化、氧化还原电位(ORP)以及重金属含量进行了检测。结果表明, 生物淋滤9 d混合菌对于As、Cr、Cu、Ni和Zn的去除效果最好; 去除率分别达到了96.09%、93.47%、98.32%、97.88%和98.60%。对于Cd和Pb混合菌生物淋滤的去除率在第6天之后迅速下降, 但是A. t单菌淋滤保持较高的去除率。     

疏剪不同穗位小穗对小麦籽粒结实和粒重的影响

１９９７～１９９８年在河南省农作物品种展览中心以中大穗小麦品种温麦６号为材料,设计了去除不同穗位小穗的试验。结果表明,去除不同位小穗对结实粒数和粒重的影响不同, 除顶端小穗的粒数下降较多,穗粒重最低,却除基部小重申对结实粒数和粒重的影响较小,穗粒数和粒重下降较少;却除中部小穗对结实粒数影响较大,穗粒数量小,其穗粒重因剩余籽粒单粒重增加而得以一定程度补偿。     

脱除游离棉酚乳酸菌的分离鉴定及益生性能研究

从藜麦茎叶样品中筛选分离出乳酸菌株,测定菌株脱除游离棉酚能力,通过人工胃液、人工肠液耐受实验、抑菌实验、抗生素敏感实验及表面特性研究菌株各项性能,并通过生理生化及16S rDNA法对菌株进行鉴定。结果表明,筛选出1株高效游离棉酚脱除乳酸菌LR002,其游离棉酚脱除率为62.87%,该菌株具有高效的耐人工胃液、肠液效果,且具有广谱抑菌作用,对抗生素不敏感,经鉴定该菌株为植物乳杆菌（Lactobacillus plantarum）。本研究旨在筛选出高效游离棉酚脱除乳酸菌菌株,为棉粕在畜禽生产中的合理利用提供参考。     

Separation of various B-cell subpopulations from mouse spleen. I. Depletion of B cells by rosetting with glutaraldehyde-fixed, anti-immunoglobulin-coupled red blood cells.

Mouse spleen cells were depleted of immunoglobulin (Ig)-bearing B cells by rosetting with glutaraldehyde-fixed, tannic acid-treated RBC coupled with antibody to mouse Ig (anti-Ig) and removing the rosetted cells by density gradient centrifugation. The method was routinely greater than 90% effective in removing B cells as assayed by the failure of anti-Ig rosette-depleted primed spleen cells to generate antibody-producing cells in vitro in response to specific antigen or of anti-Ig rosette-depleted nonprimed spleen cells to generate a polyclonal antibody response. T cells were not removed by the rosetting procedure as measured by helper T-cell activity. The greater effectiveness of the rosetting procedure in removing potential IgG-secreting, non-IgM-bearing B cells is shown relative to other commonly used B-cell depletion procedures. Because the RBC in the rosetting reagent are fixed with glutaraldehyde, the rosetting reagent is stable for many months. Such stability makes constantly available a convenient means for B-cell removal, as well as reducing consumption of antisera.     

花冠对紫茉莉繁殖适合度的影响

以授粉后具花闭合特性的紫茉莉为研究材料,通过在不同天气状况下作去花冠和存留花冠处理,观察花冠对花粉活力、柱头可授性及结实率等繁殖特性的影响。结果表明:紫茉莉自然存留花冠比去花冠的花粉活力、柱头可授性、柱头上的花粉数及柱头上花粉萌发率各指标达最高值的时间重叠性更强,并以阴天存留花冠的最强。存留花冠通过这种时间的重叠性来保证花粉在柱头上的萌发,产生了有利的繁殖适合度。越晚去花冠结实率越高,结实率呈现花闭合自然存留花冠>花冠闭合期去花冠>散粉初期去花冠>花冠展开期去花冠的规律。因此,花冠对紫茉莉繁殖适合度具有利影响。紫茉莉花冠的存留提高了繁殖适合度,增强了对环境的适应能力。     

In vitro deadenylation of mammalian mRNA by a HeLa cell 3'' exonuclease.

We have identified a 3' exonuclease in HeLa cell extracts which deadenylates mammalian mRNA and leaves the mRNA body intact after poly(A) removal. Only homopolymeric adenosine tails located at the 3' end were efficiently removed by the exonuclease. The poly(A) removing activity did not require any specific sequences in the mRNA body either for poly(A) removal or for accumulation of the deadenylated mRNA. We conclude that the poly(A) removing activity is a 3' exonuclease since (i) reaction intermediates gradually lose the poly(A) tail, (ii) degradation is prevented by the presence of a cordycepin residue at the 3' end and (iii) RNAs having internally located poly(A) stretches are poor substrates for degradation. The possible involvement of the poly(A) removing enzyme in regulating mRNA translation and stability is discussed.     

Improving the performance of positive selection inference by filtering unreliable alignment regions

Errors in the inferred multiple sequence alignment may lead to false prediction of positive selection. Recently, methods for detecting unreliable alignment regions were developed and were shown to accurately identify incorrectly aligned regions. While removing unreliable alignment regions is expected to increase the accuracy of positive selection inference, such filtering may also significantly decrease the power of the test, as positively selected regions are fast evolving, and those same regions are often those that are difficult to align. Here, we used realistic simulations that mimic sequence evolution of HIV-1 genes to test the hypothesis that the performance of positive selection inference using codon models can be improved by removing unreliable alignment regions. Our study shows that the benefit of removing unreliable regions exceeds the loss of power due to the removal of some of the true positively selected sites.     

On donor-acceptor relations and growth correlation in shoot development of the pedunculate oak germling

We studied the first cycle of shoot growth of the Quercus robur germlings in which the donor-acceptor relations were changed by removing a part of cotyledons, growing in darkness, or removing growing leaf blades. In all cases, the greatest changes in growth and growth correlations were observed in the shoot upper metameres carrying leaf blades and the least, in lower metameres preformed in the acorn embryo. The removal of growing leaves changed the rhythm of shoot growth.     

Possibilities of avoiding an intra-femoral increase in pressure during hip revision surgery]

An earlier experimental study carried out by us revealed an increase in intrafemoral pressure during removal of cement in hip revision arthroplasty. This increase is greater while removing cement from the distal femoral shaft. Maximum pressure increases occurred while removing the medullary plug (cement stopper), and the measured pressure of more than 150 mmHg is associated with an increased risk of fat embolism. The present study shows that this phenomenon can be avoided through the use of cannulated instruments.     

民勤绿洲白刺灌丛沙堆不同演化阶段表面抗蚀性及其影响因素

通过测定甘肃民勤绿洲外围不同演化阶段灌丛沙堆表面抗剪强度,选取稳定阶段灌丛沙堆,定位观测结皮和植被去除前后灌丛沙堆表面侵蚀速率,研究了白刺灌丛沙堆表面抗蚀性及其影响因素,结果表明：稳定阶段灌丛沙堆土壤抗剪强度最大,在0.31～0.79 kg·cm^-2,雏形阶段最小,在0.06～0.15 kg·cm^-2,稳定阶段灌丛沙堆的土壤抗剪强度显著高于其它演化阶段（P＜0.01）;除退化阶段外,其它演化阶段不同坡位土壤抗剪强度差异均不显著（P＞0.05）.去除结皮和植被后,稳定阶段灌丛沙堆表面抗剪强度迅速下降,去除前后差异显著（P＜0.01）,去除后不同坡位差异不显著（P＞0.05）.保留结皮和植被,灌丛沙堆不同部位均出现堆积;去除结皮但保留植被,灌丛沙堆堆积量开始减小;去掉植被保留结皮,灌丛沙堆表面堆积量迅速减小;去除结皮和植被后,灌丛沙堆表面出现严重风蚀.     

Covariation between clutch size, egg weight and egg shape: comparative evidence for chelonians

The variation in reproductive variables is documented both within and across species of chelonians. At both the generic and family levels, egg weight and clutch size show positive, significant correlations with adult carapace length. There is a negative correlation across both genera and families between clutch size and egg weight after removing the effects of body size, suggesting an evolutionary trade-off between these two life-history characteristics. However, the trade-off is not complete, since clutch size is positively correlated with clutch weight after removing the effects of body size. Terrestrial species lay fewer and larger eggs for their size than freshwater or marine species, but this association is statistically confounded by the fact that chelonian families form ecological groups. There is no significant association between habitat and clutch weight after removing the effects of body size, nor between latitude and either egg weight or clutch size, but temperate species have a heavier clutch weight after removing the effects of body size. Larger species lay eggs that are more spherical, but after controlling for body size, egg shape is not associated with clutch size. The patterns of covariation between adult weight, egg weight and clutch size contrast with those reported for birds and mammals, and some reasons for these differences are discussed.     

Comparison of Two Chemicals for Removing an Entocytherid (Ostracoda: Crustacea) Species from Its Host Crayfish (Cambaridae: Crustacea)

Entocytherids are epifauna on larger crustaceans. We assessed the effectiveness of chlorobutanol and carbonated water for removing entocytherid, Ankylocythere sinuosa, from crayfish, Procambarus clarkii. This was done using different exposure times and by assessing entocytherid and crayfish survival, together with the number of entocytherids removed. According to our results, chlorobutanol submersion of crayfishes in shorter time periods is more effective for removing entocytherids without killing the crayfish host. However, carbonated water submersion is better to extract larger amounts of living entocytherids. Finally, both chemicals are appropriate tools to establish standardised protocols for removing entocytherids from crayfish for ecological studies because the proportions of removed entocytherids per crayfish become constant whatever the entocytherid load of the crayfish. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The effect of partial defoliation on yield of sugar beet

Sugar-beet plants were defoliated during growth in seven experiments from 1968 to 1974 either (1) by removing each leaf as it became fully expanded or (2) by removing with scissors as soon as possible all leaves except certain groups up to leaf 50 , but mainly 6 to 20 , or (3) by treating the growing point chemically or mechanically in an attempt to stop the production of leaves after the twentieth. Removing mature leaves decreased yields considerably, but removing all leaves except 6–20 did not decrease significantly total dry matter yield of the whole plant and in one experiment increased it by 7% and root weight by 15%. Remaining leaves had a greater photosynthetic efficiency as measured by growth analysis and a ¹⁴C0₂ feeding technique because they were less shaded or there was reduced competition for some nutrient or essential growth component. Additional leaves formed beyond the twentieth resulted in a proportionately lower photosynthetic efficiency of all leaves, but attempts to treat the plant to stop production of new leaves beyond the twentieth were inconclusive.     

On Donor–Acceptor Relations and Growth Correlation in Shoot Development of the Pedunculate Oak Germling

We studied the first cycle of shoot growth of the Quercus robur L. germlings in which the donor–acceptor relations were changed by removing a part of cotyledons, growing in darkness, or removing growing leaf blades. In all cases, the greatest changes in growth and growth correlations were observed in the shoot upper metameres carrying leaf blades and the least, in lower metameres preformed in the acorn embryo. The removal of growing leaves changed the rhythm of shoot growth.     

Mediator-induced macrophage activation, as shown by enhanced cytotoxicity for tumor, requires macrophage surface fucose and sialic acid

Macrophage-activating factor (MAF) activates macrophages so that their cytotoxic capacity is enhanced. This effect of MAF is inhibited by removing fucose from the macrophage cell surface by incubation with fucosidase, or by removing sialic acid by treatment with neuraminidase. After incubation with fucosidase or neuraminidase the average inhibition of cytotoxicity was 92 and 73%, respectively. β-Galactosidase had no effect. Addition of the specific products, fucose or sialic acid, to the incubation mixture of macrophages and enzyme blocked the effect of the enzymes. Taken together these observations indicate that macrophage surface fucose and sialic acid are essential for the interaction of MAF with macrophages which results in enhanced cytotoxicity for tumor cells.     

疫霉属菌种的液氮超低温保藏

对疫霉属的15个种68株菌和霜疫霉2株菌进行了液氮超低温的保藏试验并得到成功。比较了冷冻速度、保护剂和解冻速度对菌存活的影响。严格控制每分钟降温摄氏1度直到-40℃后再放入液氮罐中,对疫霉和霜疫霉来说都是非常必要的。这种降温程序可通过简单设备人工操作达到。而直接由室温降到-150℃以下会损伤菌种以致死亡。在所用的保护剂中,不论10％甘油还是5-15％二甲基亚砜都能起到保护作用。尚看不出对那种保护剂有特别的要求,似可任意选用。至于解冻条件,由液氮中取出放置在38℃水浴中快速融化与在20℃水浴中中等速度融化效果相等,对菌的成活都没有太大影响。我们的试验肯定了在有保护剂存在下,用慢速冷冻可以在液氮中保存疫霉和霜疫霉。     

体外去除胆固醇菌株的筛选及其作用机理研究

从青年人肠道中筛选分离,鉴定得到8株乳杆菌,进行胆固醇去除、耐酸和耐胆汁盐实验,发现两株植物乳杆菌Lp529和Lp501同时具有较高的体外去除胆固醇能力和耐胆汁盐及耐酸性能。通过对它们胆固醇去除过程和胆固醇在相应固液相中分布情况的实验分析,表明：Lp501与Lp529去除胆固醇的机理有差别,存在菌株特异性。研究还发现,被菌株吸收的胆同醇没有被代谢为其他物质,并可在条件适合时重新释放出来。     

细菌荚膜多糖的分离纯化研究进展

荚膜多糖是细菌的保护性抗原和毒力因子,也是细菌疫苗最重要的靶抗原之一,其分离纯化是制作疫苗的首要步骤。本文从去除菌体、收集总糖、去除菌体核酸和蛋白质、去除内毒素等基本工艺步骤,对现有的工艺和目前的工艺进展进行了综述,重点阐述了中空纤维、深层过滤、超滤、酶水解、柱层析等方法在荚膜多糖分离纯化中的应用进展。     

Nipple or areolar reduction with simultaneous breast augmentation

Patients requesting nipple or areolar reduction often desire simultaneous breast augmentation. A technique is described for implant placement by means of a nipple base incision with either nipple reduction or intraareolar reduction. Nipple reduction is accomplished by removing a ring of skin from the base of the nipple, while areolar reduction is performed by removing a donut-shaped area of skin whose inner diameter is at the nipple base. The elasticity of the areolar skin allows for access for saline implant placement. The resulting scar is well concealed. Results from 15 patients demonstrate that the technique is safe, practical, and appears to pose no increased risk of sensory changes to the nipple.