纳米氧化锌消毒小蓟外植体应用研究

为使纳米氧化锌在组织培养中达到最佳消毒效果,以小蓟叶片外植体为材料,建立纳米氧化锌消毒的组织培养无菌体系。结果表明:纳米氧化锌浓度为1~7g·L~(-1)时,对小蓟外植体消毒效果逐渐提升,褐化率也逐渐升高,不同浓度纳米氧化锌对愈伤组织的诱导和生长没有明显的影响。纳米氧化锌最佳消毒处理浓度为5g·L~(-1),处理外植体20min。2g·L~(-1)纳米氧化锌+0.1%升汞消毒,外植体大约20%有污染,愈伤组织生长良好。3g·L~(-1)纳米氧化锌+0.1%升汞达到最佳的消毒效果,但愈伤组织诱导被抑制,生长缓慢。     

湛江市海水鱼中副溶血性弧菌的分离 鉴定及致病性分析

为了解湛江市海水动物副溶血性弧菌的带菌感染率及其致病性,从湛江市水产品市场随机采集海水鱼样品30份,根据中华人民共和国国家标准和进出口标准规定的副溶血性弧菌的检验方法,结合科玛嘉弧菌显色培养基分离试验,对采集样品进行了副溶血性弧菌的分离与鉴定;并用神耐川试验、溶血试验和脲酶试验检测了分离菌株的致病性。结果显示：30份海水鱼样品分离得到10株副溶血性弧菌,检出率为33.33%。其中,神耐川试验溶血强阳性5株,弱阳性2株,阴性3株;在3.5%NaC l兔血琼脂平板上,本试验分离到的10株副溶血性弧菌均呈现较强溶血作用;10株分离菌株脲酶试验均为阴性。     

氯化铵和氯化钾对太湖黄泥土磷的吸持动力学影响的研究

土壤中磷的移动性、植物有效性和对水体环境的潜在危害性与土壤对磷的吸持反应有关,而铵钾磷共施是农业生产中的普遍现象,因此,本文通过批量培养法,研究了相同摩尔数的氯化铵和氯化钾对磷的吸持动力学的影响,并对磷的吸持动力学进行了不同模型的拟合.结果表明,氯化铵、氯化钾均显著增加了土壤对磷的吸持,在培养初期(5 min),相同摩尔数的氯化铵、氯化钾对磷的吸持量无显著差异,但在15 min ～ 10 d阶段,相同摩尔数的氯化钾对磷吸持量的影响显著大于相同摩尔数的氯化铵.而铵钾共施时,两者对磷的吸持具有协同作用,并主要表现为氯化钾的作用.氯化铵对土壤磷吸持总量无显著影响,氯化钾则显著增加了土壤磷吸持总量,氯化钾和氯化铵处理土壤磷吸收总量则无显著差异.通过比较不同模型拟合的决定系数(R2)大小,不同模型拟合效果顺序为Elovich方程＞双常数方程＞Parabolic扩散方程＞零级方程＞一级方程＞二级方程.     

蔬菜作物长期施用含氯肥对土壤相关性质的影响

 对两组各种植21茬不同蔬菜作物连续施用含氯肥(氯化铵)11年的长期定位试验进行分析。结果表明，连续施入氯化铵，土壤pH较初始土壤pH降低0.42～0.45。施用含氯肥，0～20 cm土层pH与氯离子含量呈显著负相关。而施用非含氯肥氯离子与pH无相关性。11年20茬蔬菜总计施入氯9 702 kg·ha-1，两组处理区0～60 cm土层氯离子残留率分别为6.2%和7.2%。施入的氯76.6%和74.7%被淋洗到60 cm土层以下。植株带走的氯分别占17.2%和18.1%。施用含氯肥处理土壤氯离子含量显著高于非含氯肥料处理。表层土壤氯离子含量变幅较大，尤以返盐期表层氯离子含量变化最大。11年未施氯处理，绝大多数时间土壤氯离子含量在100 mg·kg-1以下，变幅很小。蔬菜作物长期施氯，土壤氯离子并未出现随施氯年限增加而在土壤中有逐年累积的趋势。     

Reconstitution and phosphorylation of chloride channels from airway epithelium membranes

Airway epithelial chloride secretion is controlled by the apical-membrane chloride permeability. Purified apical-membrane vesicles from bovine tracheal epithelium have now been shown to contain functional chloride channels by using the planar-bilayer technique. Three types of chloride channels were observed; a voltage-dependent, calcium-independent, 71-picoSiemen (in 150 mM NaCl) channel accounted for more than 80 percent of the vesicular chloride conductance and was under strict control of phosphorylation. The channel underwent a fast rundown in less than 2 to 3 minutes of recording, and reactivation required in situ exposure to a phosphorylating "cocktail" containing the catalytic subunit of the adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase. Mean open time and open probability were increased after phosphorylation, whereas slope conductance remained unchanged. Thus, metabolic control of tracheal chloride single channels can now be studied in vitro.     

氯素对烤烟生长发育和经济性状影响的研究进展

氯是一种烟草生长必需但限量使用的元素。该文就氯素对烤烟生长发育和经济性状的影响进行了介绍,从保持土壤氯平衡的角度出发,提出不同烟区应根据缺氯状况适当补充一定量的氯来提高经济性状。     

南疆棉花种子包衣缓释缩节胺化控技术的初步研究

[目的]应用种子包衣缓释缩节胺化控技术,简化棉花栽培管理措施和节本增效.[方法]采用高、中、低三个剂量的缓释缩节胺包衣,研究其对棉花生长发育、农艺及经济性状等的影响.[结果]缓释缩节胺包衣对棉花生长发育、农艺性状的影响与常规喷施相似,中、高剂量处理均能够有效防止棉花打顶前的徒长,各剂量对产量无显著影响,合适的剂量还具有增产趋势.[结论]棉花打顶前,缩节胺的持续释放能够代替常规喷施调控棉花生长.     

Regulation of chloride channels by protein kinase C in normal and cystic fibrosis airway epithelia

Apical membrane chloride channels control chloride secretion by airway epithelial cells. Defective regulation of these channels is a prominent characteristic of cystic fibrosis. In normal intact cells, activation of protein kinase C (PKC) by phorbol ester either stimulated or inhibited chloride secretion, depending on the physiological status of the cell. In cell-free membrane patches, PKC also had a dual effect: at a high calcium concentration, PKC inactivated chloride channels; at a low calcium concentration, PKC activated chloride channels. In cystic fibrosis cells, PKC-dependent channel inactivation was normal, but activation was defective. Thus it appears that PKC phosphorylates and regulates two different sites on the channel or on an associated membrane protein, one of which is defective in cystic fibrosis.     

铁钙复合法处理高浓度含磷农药废水的研究

[目的]探索由生产氟磺胺草醚而产生的高浓度含磷废水的除磷方法。[方法]用氯化钙、氯化铁及铁钙复合法对农药厂生产氟磺胺草醚而产生的高浓度含磷废水进行处理。[结果]氯化钙处理法的最佳pH值为8,最佳投药量为5.33 g/L,去除率为99.45%,处理成本为10.80元/kg磷;氯化铁处理法的最佳pH值为7,最佳投药量为6.50 g/L,去除率为99.08%,处理成本为56.89元/kg磷;铁钙复合法处理的最佳pH值为8,氯化钙最佳投药量为5.33 g/L,氯化铁最佳投药量为60 mg/L,此时去除率达99.91%,处理成本为11.28元/kg磷;处理后的废水可达到《污水综合排放标准（GB 8978—1996）》1级排放标准。[结论]铁钙复合法对该种农药废水中高浓度无机磷具有良好的去除效果。     

TMEM16A, a membrane protein associated with calcium-dependent chloride channel activity

Calcium-dependent chloride channels are required for normal electrolyte and fluid secretion, olfactory perception, and neuronal and smooth muscle excitability. The molecular identity of these membrane proteins is still unclear. Treatment of bronchial epithelial cells with interleukin-4 (IL-4) causes increased calcium-dependent chloride channel activity, presumably by regulating expression of the corresponding genes. We performed a global gene expression analysis to identify membrane proteins that are regulated by IL-4. Transfection of epithelial cells with specific small interfering RNA against each of these proteins shows that TMEM16A, a member of a family of putative plasma membrane proteins with unknown function, is associated with calcium-dependent chloride current, as measured with halide-sensitive fluorescent proteins, short-circuit current, and patch-clamp techniques. Our results indicate that TMEM16A is an intrinsic constituent of the calcium-dependent chloride channel. Identification of a previously unknown family of membrane proteins associated with chloride channel function will improve our understanding of chloride transport physiopathology and allow for the development of pharmacological tools useful for basic research and drug development.     

烟田施用氯化钾对烤烟生长发育、产量和品质的影响

为明确百色烟区烟田氯肥的合理施用量,以烤烟(Nicotiana tabacum L.)品种云烟85为供试材料,研究了百色烟区烟田施用氯化钾对烤烟产量及品质的影响。结果表明,烟田施用氯化钾可以在一定程度上改善烟叶的农艺性状;烤烟产量、产值随氯化钾施用量的增加呈先增加后降低趋势,并以22.5kg/hm2、45.0kg/hm2处理较高,产量较不施氯化钾处理(CK)分别提高27.11%、21.80%,产值分别提高41.73%、32.32%;施用氯化钾还可改善烟叶的化学品质和评吸质量,以施氯化钾22.5～67.5kg/hm2的烟叶化学成分含量适宜,K2O/Cl、总氮/烟碱、还原糖/烟碱值比较协调,烟叶评吸质量好;随氯化钾用量的增加,烟叶中氯含量增加明显。综合分析,生产上百色烟区烟田氯化钾施用量以22.5～45.0kg/hm2较为适宜。     

The role of chloride transport in postsynaptic inhibition of hippocampal neurons

Hippocampal inhibitory postsynaptic potentials are depolarizing in granule cells but hyperpolarizing in CA3 neurons because the reversal potentials and membrane potentials of these cells differ. Here the hippocampal slice preparation was used to investigate the role of chloride transport in these inhibitory responses. In both cell types, increasing the intracellular chloride concentration by injection shifted the reversal potential of these responses in a positive direction, and blocking the outward transport of chloride with furosemide slowed their recovery from the injection. In addition, hyperpolarizing and depolarizing inhibitory responses and the hyperpolarizing and depolarizing responses to the inhibitory neurotransmitter gamma-aminobutyric acid decreased in the presence of furosemide. These effects of furosemide suggest that the internal chloride activity of an individual hippocampal neuron is regulated by two transport processes, one that accumulates chloride and one that extrudes chloride.     

氯离子诱导的钢筋混凝土结构耐久性研究

从影响氯离子传输的因素、临界氯离子浓度、氯离子向混凝土内传输的机理、氯离子传输预测模型等方面对因氯离子诱导的钢筋腐蚀造成的钢筋混凝土（RC）结构耐久性能退化问题进行了评述,提出了需要进一步研究的问题.     

Autonomic regulation of a chloride current in heart

In isolated heart cells, beta-adrenergic receptor stimulation induced a background current that was suppressed by simultaneous muscarinic receptor stimulation. Direct activation of adenylate cyclase with forskolin also elicited this current, suggesting regulation by adenosine 3',5'-monophosphate (cAMP). This current could be recorded when sodium, calcium, and potassium currents were eliminated by channel antagonists or by ion substitution. Alteration of the chloride equilibrium potential produced changes in the reversal potential expected for a chloride current. Activation of this chloride current modulated action potential duration and altered the resting membrane potential in a chloride gradient-dependent manner.     

土壤铝存在形式对马铃薯抵抗侵染软腐病菌的影响

[目的]从土壤化学角度探讨西北地区适合种植马铃薯的病理原因。[方法]通过模拟酸性及碱性土壤中铝的2种形式氯化铝(Al3+)和胶体铝(Al(OH)3),研究马铃薯块茎受软腐病菌侵染时土壤胶体态的铝对块茎过氧化氢积累及病程蛋白表达的影响。[结果]土壤铝的溶出直接导致马铃薯块茎切片细胞的死亡。马铃薯感染软腐病菌过程中,Al3+处理加速了马铃薯的感病,而Al(OH)3则延缓了马铃薯的感病。Al3+处理在加速马铃薯细胞死亡的同时产生大量的H2O2,而Al(OH)3在产生较高H2O2积累的同时并未造成明显的马铃薯细胞死亡。SDS-PAGE电泳分析表明,Al(OH)3处理的马铃薯明显不同于Al3+及空白对照。[结论]马铃薯块茎在感病过程中受土壤铝溶出率及铝形态变化的双重影响。     

黄河水化学需氧量测定中氯离子的干扰及消除

[目的]消除黄河水化学需氧量测定中氯离子的干扰。[方法]通过模拟试验的方法量化了氯离子对化学需氧量(COD)测定的干扰程度,并在黄河水实际监测工作中进行了验证。[结果]氯离子对水样COD测定的干扰程度与氯离子含量呈正相关,其影响系数与理论值基本相当。黄河水质监测中,氯离子对COD测定的影响不容忽视,必须加入硫酸汞以消除氯离子的干扰。[结论]该研究可为水体化学需氧量测定中氯离子干扰的消除提供科学方法。     

二氯化锰腹腔染毒对血细胞数及骨髓细胞微核率的影响

小鼠腹腔染毒不同浓度二氯化锰,12 h一次,连续染毒4次.染毒结束后,测定血液中白细胞(WBC)总数、白细胞分类(DC)计数、红细胞(RBC)总数、血红蛋白(Hb)含量及骨髓细胞微核率,以探讨锰对机体血液的毒性作用及机体的遗传毒性作用.实验表明小鼠染毒低浓度(25mg/kg)二氯化锰,RBC、Hb含量与阴性对照组比差异显著(p＜0.05);不同剂量二氯化锰组与阴性组比,WBC、DC计数未见显著差异,骨髓细胞微核率显著高于对照组(p＜0.05).     

Structure of the light-driven chloride pump halorhodopsin at 1.8 A resolution

Halorhodopsin, an archaeal rhodopsin ubiquitous in Haloarchaea, uses light energy to pump chloride through biological membranes. Halorhodopsin crystals were grown in a cubic lipidic phase, which allowed the x-ray structure determination of this anion pump at 1.8 angstrom resolution. Halorhodopsin assembles to trimers around a central patch consisting of palmitic acid. Next to the protonated Schiff base between Lys(242) and the isomerizable retinal chromophore, a single chloride ion occupies the transport site. Energetic calculations on chloride binding reveal a combination of ion-ion and ion-dipole interactions for stabilizing the anion 18 angstroms below the membrane surface. Ion dragging across the protonated Schiff base explains why chloride and proton translocation modes are mechanistically equivalent in archaeal rhodopsins.     

植物生长调节物质对黄花乌头性状及产量影响的研究

试验分别采用三种不同浓度的多效唑、矮壮素、缩节胺对黄花乌头进行叶面喷施,通过使其矮化,来研究不同药剂对该植物的地上、地下农艺性状以及经济产量的影响。结果表明：500mg.L-1的矮壮素处理对其植株矮化效果最佳;150mg.L-1的多效唑处理植株的倒伏率最低为15.6%;500mg.L-1的矮壮素处理其子根个数最多;500mg.L-1的矮壮素处理其产量提高最大,较对照组提高43.04%。结论是利用生物调节剂多效唑、矮壮素处理黄花乌头对其农艺性状及产量都有明显的影响。     

氯化钠对分蘖葱头根尖细胞有丝分裂的影响及其致畸效应

以分蘖葱头根尖为试验材料,研究了氯化钠对分蘖葱头根尖的毒性效应。用不同浓度(0.05、0.1、0.2、0.3 mol/L)的氯化钠水溶液对分蘖葱头根尖细胞染毒12 h、24 h、48 h,观察分蘖葱头根尖细胞有丝分裂指数、微核率以及染色体畸变情况。结果表明:在试验剂量范围内,随着氯化钠水溶液浓度的升高,染毒时间增长,分蘖葱头根尖细胞的有丝分裂指数逐渐降低,染色体畸变率和微核率逐渐升高,并且均在氯化钠水溶液浓度为0.3 mol/L、染毒时间为48 h时达到最大值,说明氯化钠是一种胁迫因子。