大茨藻的碎屑形成过程

在实验室条件下,大茨藻(Najas major)死亡前后的形态变化可分为如下几个阶段：临界期或死亡前期;细胞核变色期;细胞质收缩期和胶体形成期。作者把细胞核变色期定为大茨藻的碎屑开始期。同时,还考察了天然条件下大茨藻死亡后形态的降解情况。     

大茨藻的碎屑形成过程

在实验室条件下,大茨藻(Najas major)死亡前后的形态变化可分为如下几个阶段:临界期或死亡前期;细胞核变色期;细胞质收缩期和胶体形成期。作者把细胞核变色期定为大茨藻的碎屑开始期。同时,还考察了天然条件下大茨藻死亡后形态的降解情况。       

婴儿股静脉穿刺方法的改进

婴儿股静脉穿刺抽血是危重症婴儿抽血的主要途径，如紧急抢救，可作为首要的给药途径。因此，改进婴儿股静脉穿刺方法，提高穿刺的成功率能为抢救婴幼患儿赢得时间。我科于2005年～2006年采用改进后的新法穿刺股静脉，成功率高，现介绍如下。     

经皮穿刺抽取大鼠脑脊液方法的改良

目的: 改进传统经皮穿刺抽取脑脊液的方法,提高采集大鼠脑脊液动物存活率。方法: 90只SD大鼠随机分为对照组、传统穿刺组和改良穿刺组(每组30只)。对照组不进行穿刺。传统穿刺组按反握抓持法进行穿刺取样。改良穿刺组采用左手固定大鼠头部,将其抬高至约135°,右手正握改良1 ml注射器,以枕骨隆突和第一颈椎为标志定位枕骨大孔,在枕骨大孔中心偏下平行进针,抽取脑脊液。分别于第1、4、7日抽取大鼠脑脊液,每次抽取记录取样时间、采集量、脑脊液性状,抽取后3 d观察大鼠存活情况,选取存活大鼠进行重复采样。结果: 传统经皮穿刺取样法采样成功率为63.33%,三次重复采样动物存活率为10%;改良经皮穿刺取样法采样成功率为86.67%,三次重复采样动物存活率为50%,相比传统采样有显著升高(P＜0.01)。结论: 改良经皮穿刺取样法操作简单,耗时少,成功率高。操作无需定位设备,单人可以完成。动物反复取样存活率高,方便进行脑脊液重复采样。     

心理干预对手术室患儿静脉穿刺时不良情绪的影响

目的:研究并探讨心理干预对手术室患儿静脉穿刺时不良情绪的影响.方法:以我院2010年1月1日-2012年1月1日期间进行静脉穿刺的1800例患儿为研究对象,其年龄为1-6岁之间,将所有的患儿进行随机分组处理,并使治疗组和对照组均能够由900例患儿组成,对照组的患者进行常规的护理与操作,而治疗组的患者则进行科学的心理干预,以减少惠儿穿刺时的焦虑和恐惧心理,使其积极的配合治疗,以提高静脉穿刺的成功率,并将两组患儿的临床结果进行对比分析.结果:治疗组患儿无论在穿刺的主动性还是在穿刺的成功率等方面均显著的优于对照组患儿,差异具有较为显著的统计学意义(P＜0.05).结论:对于手术室进行静脉穿刺的患儿而言,进行科学的心理干预不仅有助于提高患儿配合穿刺的主动性,更加有助于消除其恐惧与不安的情绪,从而提高穿刺的成功率,值得在临床中推广与应用.     

五指山小型猪两种股动脉穿刺方法的比较

目的比较五指山小型猪在急性心肌梗死造模前行股动脉穿刺所使用的两种方法的成功率和并发症发生率以及所花费时间,为动物实验时行股动脉穿刺提供依据。方法拟行股动脉穿刺的五指山小型猪16头随机分为两组即切开直视穿刺组（n：8）和超声引导穿刺组（n=8）,比较两组穿刺的成功率、并发症发生率以及穿刺所花费时间。结果切开直视穿刺组的成功率及感染发生率均无差异,但出血发生率前者显著低于后者（P〈0．05）,且花费时间也明显少于后者（P〈0．05）。结论切开直视股动脉穿刺术是一种成功率高,安全性好,花费时间相对较少的方法。     

改进后的静脉留置针穿刺方法及护理

目的：探讨头皮式留置针穿刺方法的改进,以提高穿刺的成功率,减轻病人的痛苦。方法对我科2013年1～12月住院治疗的112例术前患者,采用改进后的静脉留置针穿刺方法进行穿刺,同时给予相关护理,观察其临床效果。结果改进后的静脉留置针穿刺方法显著减少了静脉穿破的几率。结论改进后的静脉留置针穿刺方法可有效的减轻反复穿破血管给患者带来的痛苦及经济负担,提高了病人的满意度,也提高了护理质量。     

年老体弱患者手背浅静脉穿刺方法的改进与应用

静脉输液是临床护理工作的基本操作．在护理工作中占仃非常重要的地位,在很大程度上决定着护理人员操作水平的高低及患者的治疗效果。在静脉输液的过程中,尤其是对老年、体弱的病人或应用特殊药物时．运刷常规静脉输液的方法常会出现穿刺失败或引发静脉炎而增加病人的痛苦。     

两栖类早期发育中一内胚层形成和神经板发育之垂直的和平面的诱导作用

中-内胚层诱导和神经诱导都需要平面的和垂直的诱导相互作用;中胚层诱导开初是一个平面诱导过程,继之以一个垂直诱导,以实现最终的区域分化,而神经诱导则必须有最初的垂直相互作用,以实现激发和转化过程。这些垂直的诱导作用,继之以在外胚层内传播的同源诱导作用,决定神经板的形状和大小,以及其区域分化。对于神经板的背面集中和伸长,激发作用和后来的转化作用似乎都是必需的。     

棉株上烟粉虱若虫种群的垂直分布与统计方法研究

对烟粉虱Bemisiatabaci在棉花植株上的垂直分布调查发现 ,烟粉虱在棉株各部位均有分布 ,且分布极不均匀 ,统计分析表明棉株各部位间烟粉虱的种群数量存在显著的差异。棉花顶部烟粉虱的若虫数量约占全棉株若虫总量的 1 6%,通过对棉株各部位烟粉虱的若虫数量与整株若虫总量的回归分析 ,建立了相应的回归方程式     

Decomposition of Plant Debris by the Nematophagous Fungus ARF

In the study of the biological control of plant-parasitic nematodes, knowledge of the saprophytic ability of a nematophagous fungus is necessary to understand its establishment and survival in the soil. The objectives of this study were (i) to determine if the nematophagous fungus ARF (Arkansas Fungus) shows differential use of plant residues; and (ii) to determine if ARF still existed in the soil of a field in which ARF was found originally and in which the population level of Heterodera glycines had remained very low, despite 15 years of continuous, susceptible soybean. Laboratory studies of the decomposition of wheat straw or soybean root by ARF were conducted in two separate experiments, using a CO₂ collection apparatus, where CO₂-free air was passed through sterilized cotton to remove the microorganisms in the air and then was passed over the samples, and evolved CO₂ was trapped by KOH. Milligrams of C as CO₂ was used to calculate the percentage decomposition of the plant debris by ARF. Data indicated ARF decomposed 11.7% of total organic carbon of the wheat straw and 20.1% of the soybean roots in 6 weeks. In the field soil study, 21 soil samples were taken randomly from the field. Only 3 months after the infestation of the soil with H. glycines, the percentage of parasitized eggs of H. glycines reached 64 ± 19%, and ARF was isolated from most parasitized eggs of H. glycines. Research results indicated ARF could use plant residues to survive.     

冰雪灾害对粤北天然次生林的损害及产生的林冠残体量

采用样地调查和取样,研究了2008年初中国南方冰雪灾害对粤北天然次生林的损害特征及其产生的林冠残体量.结果表明,灾害对粤北天然林造成严重损害,林木受害特征主要是胸径较大的植株断枝、断梢和断干较多,胸径较小的容易压弯,坡度大的林分翻蔸受害率增加.灾后林地林冠残体总量为38.12～43.52 t hm-2,平均41.25 t hm-2;地表凋落叶11.79～12.87 t hm-2,平均12.47 t hm-2;灾害产生的枝、干木质残体量为24.27～30.65 t hm-2,平均28.41 t hm-2.天然常绿阔叶林产生的林冠残体量较常绿与落叶混交林和杉木人工林大,造成林地林冠残体量骤增,一方面使林地存在严重安全隐患(如发生火灾和病虫害的风险增加),另一方面大量的林冠残体归还林地、改变了森林生态系统的结构与功能.     

Getting a camel through the eye of a needle: the import of folded proteins by peroxisomes

Peroxisomes are a family of organelles which have many unusual features. They can arise de novo from the endoplasmic reticulum by a still poorly characterized process, yet possess a unique machinery for the import of their matrix proteins. As peroxisomes lack DNA, their function, which is highly variable and dependent on developmental and/or environmental conditions, is determined by the post‐translational import of specific metabolic enzymes in folded or oligomeric states. The two classes of matrix targeting signals for peroxisomal proteins [PTS1 (peroxisomal targeting signal 1) and PTS2] are recognized by cytosolic receptors [PEX5 (peroxin 5) and PEX7 respectively] which escort their cargo proteins to, or possibly across, the peroxisome membrane. Although the membrane translocation mechanism remains unclear, it appears to be driven by thermodynamically favourable binding interactions. Recycling of the receptors from the peroxisome membrane requires ATP hydrolysis for two linked processes: ubiquitination of PEX5 (and the PEX7 co‐receptors in yeast) and the function of two peroxisome‐associated AAA (ATPase associated with various cellular activities) ATPases, which play a role in recycling or turnover of the ubiquitinated receptors. This review summarizes and integrates recent findings on peroxisome matrix protein import from yeast, plant and mammalian model systems, and discusses some of the gaps in our understanding of this remarkable protein transport system.     

Comparisons of the Colonisation by Invertebrates of Three Species of Wood,Alder Leaves,and Plastic “Leaves” in a Temperate Stream

Small woody debris in streams is abundant, and may be a food source or may provide a substrate on which other food sources such as biofilm may develop, both of which may be significant to invertebrates in times of food scarcity. We examined patterns of invertebrate colonisation of small woody debris (veneers of red alder, Douglas‐fir, and western red cedar), red alder leaves, and plastic (as an inert substrate to mimic leaves). Invertebrate colonisation was high on alder leaves, but low on wood substrates and plastic, controlling for the available surface area. Detritivorous invertebrates had significantly higher colonisation rates of alder leaves versus the other four substrates, whereas predators and collectors did not (consistent with their use of these as substrates and not food). All wood decreased in mass by <15% and leaves by ∼50% over the 75 days of the experiment. For all taxa tested, there was no significant difference in their colonisation of the wood veneers versus the plastic sheets. These results suggest that wood was not directly used by these invertebrates as a food source, or that there could be similar biofilm development on the surfaces of these substrates. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Brief communication: a preliminary study on the influence of physical fruit traits on fruit handling and seed fate by white-handed Titi monkeys (Callicebus lugens)

Callicebus and the pitheciins are closely related; however, differences in their diets and dental morphology suggest that they differ in the use of mechanically protected food. We describe physical traits of fruits consumed by white-handed titi monkeys (Callicebus lugens) and determine their influence on fruit part selection and immediate seed fate after fruit handling. We tested two hypotheses about the effects of mechanical fruit traits on fruit part selection and seed fate: (1) fruits selected for seed consumption are harder than fruits selected for their fleshy parts and (2) consumed seeds are softer than seeds with other fates. In addition, we analyzed the influence of other physical fruit traits on fruit part selection and seed fate. C. lugens included 69 species in its diet, from which it mainly consumed their fleshy parts. It also consumed seeds, alone or with fleshy fruit parts, but most of them ended up close to parent trees after being dropped or spat out. The first hypothesis was supported while the second was rejected, indicating that C. lugens tends to rely on hard fruits for obtaining seeds, while seed hardness had no influence on fruit part selection and seed fate, contrasting with the pattern reported for Pithecia and Chiropotes in other studies. Ripeness was the most influential factor for fruit part and seed fate discrimination. Results suggest a tendency to sclerocarpic foraging in C. lugens when feeding on seeds.     

Statistical Evaluation of the Effect of Gemfibrosil,a Cholesterol Reducing Drug,on Some Biochemical Coronary Heart Disease Risk Variables

The evaluation is based on the clinic trial with gemfibrosil (“Gevilon”, Parke-Davis) carried out in a group of 48 patients, to whom the drug was administered in the single dose of 900 mg daily during the period of 3 months. In this paper we show the results of the treatment on five biochemical Coronary Heart Disease (CHD) risk variables: Cholesterol (CHOL), High Density Lipoprotein (HDL), Triglyccrides (TGL), Uric Acid (UA) and Glucose (GL). We are concerned with a statistical model allowing to predict which and how large changes in the considered variable can be expected in a patient taking the drug. This is done considering the “regression to the mean” effect.     

用改进的高斯—牛顿最小二乘法估测非线性生长曲线的参数

本文讨论了用改进的高斯－牛顿最小二乘法估测非线性参数的方法,并用肉鸡生长曲线拟合实例给以示范。     

Electrogenic Partial Reactions of the SR-Ca-ATPase Investigated by a Fluorescence Method

A fluorescence method was adapted to investigate active ion transport in membrane preparations of the SR-Ca-ATPase. The styryl dye RH421 previously used to investigate the Na,K-ATPase was replaced by an analogue, 2BITC, to obtain optimized fluorescence changes upon substrate-induced partial reactions. Assuming changes of the local electric field to be the source of fluorescence changes that are produced by uptake/release or by movement of ions inside the protein, 2BITC allowed the determination of electrogenic partial reactions in the pump cycle. It was found that Ca²⁺ binding on the cytoplasmic and on the lumenal side of the pump is electrogenic while phosphorylation and conformational transition showed only minor electrogenicity. Ca²⁺ equilibrium titration experiments at pH 7.2 in the two major conformations of the protein indicated cooperative binding of two Ca²⁺ ions in state E₁ with an apparent half-saturation concentration, K _M of 600 nm. In state P-E₂ two K _M values, 5 μm and 2.2 mM, were determined and are in fair agreement with published data. From Ca²⁺ titrations in buffers with various pH and from pH titrations in P-E₂, it could be demonstrated that H⁺ binding is electrogenic and that Ca²⁺ and H⁺ compete for the same binding site(s). Tharpsigargin-induced inhibition of the Ca-ATPase led to a state with a specific fluorescence level comparable to that of state E₁ with unoccupied ion sites, independent of the buffer composition. Received: 21 September 1998/Revised: 18 December 1998     

注射针头十字交叉固定法行猕猴直肠脱截除手术

目的探讨猕猴直肠脱治疗方法,为猕猴常见外科病的治疗提供参考。方法以普通注射针头十字交叉固定法,对8例病例作直肠脱截除手术。结果仅有一例因原发重症肠炎死亡外,其余均获得治愈。结论本法取材方便,固定确实可靠,容易操作。为猕猴养殖企业提供了一种简单易行的治疗手段。