低鱼粉日粮添加蛋氨酸对幼鲤生长的影响

以鱼粉10%的玉米大豆粕型幼鲤饲料为对照组(A),降低饲料鱼粉含量为5%后,分别添加不同水平的DL-蛋氨酸及其羟基类似物添加量分别为B:0.5%DL_蛋氨酸、C:0.514%蛋氨酸羟基类似物、D:0.564%蛋氨酸羟基类似物、E:0.614%蛋氮酸羟基类似物,比较研究用豆粕代替部分鱼粉,添加蛋氨酸及其羟基类似物对幼鲤的...     

安徽油茶不同品种光合生理生态特性的研究

选择安徽油茶品种大别山1号、2号、3号和4号作为试验材料,对其光合生理生态特性进行了比较研究。结果表明,不同品种日平均净光合速率差异显著,其变异范围是2.864~5.019μmol.m-2.s-1,不同品种的净光合速率大小依次为大别山1号>大别山3号>大别山4号>大别山2号。不同品种鲜叶养分含量的变异范围分别为N 10.26~10.76 mg·g-1,P 0.277~0.312 mg·g-1,K 15.90~21.93 mg·g-1;比叶重变化为234.41~273.35 g.m-2;叶绿素含量2.38~3.25 mg·g-1。油茶净光合速率受到叶片养分(N、P、K)、叶绿素含量及比叶重的影响,但不同品种表现出一定差异性。     

杜鹃花叶片N/P·LMA与生态适应性关系的初步研究

通过对龙池杜鹃属的31个种32个样品的研究发现,杜鹃叶片氮含量为1.1097%(大白杜鹃)~2.1412%(紫花杜鹃),磷含量为0.0910%(露珠杜鹃)~0.1693%(美容杜鹃),N/P为8.0958(云锦杜鹃)~17.9160(云南杜鹃),LMA为0.0716 mg/mm2(云南杜鹃)~0.2339 mg/mm2(云锦杜鹃)。N/P与LMA呈现显著的负相关(R2=0.5764,P<0.01),表明杜鹃叶片越厚,叶片N/P越低,植物相对生长速率越快,对生态环境适应性越强。     

川麦42/川农16重组自交系群体中小麦迟α-淀粉酶(LMA)的遗传分析

利用川麦42/川农16的重组自交系(recombined inbreed lines,RILs)群体,采用双抗体夹心酶联免疫吸附(ELISA)试剂盒,对迟熟α-淀粉酶(Late maturityα-amylase,LMA)进行了测试;选用7B染色体上的3对与LMA相关的SSRs引物(Xgwm577,Xwmc276,Xwmc273),对群体中标记与LMA的相关性进行了验证;同时对LMA和降落值(Falling Number,FN)的相关性进行了分析.结果表明:①LMA是受一对基因控制;②3对SSRs引物(Xgwm577,Xwmc276,Xwmc273)在MILs中对LMA的检测没有作用.③在本试验的MILs中,LMA的存在对降落值又重要影响,同时降落值还受其它遗传控制.     

Inheritance of Late Maturity α-amylase （LMA） in a Recombinant Inbreed Lines of Chuanmai 42 Crossed with Chuannong 16

[Objective] To study the inheritance and possible molecular marker of α-LMA and their relations to falling number. [Method] Recombined inbreed lines (RILS) of Chuanmai 42 (LMA genotype) crossed with Chuannong 16 (no LMA) were employed to test the late maturity α-amylase (LMA) by EL ISA kits,the Falling Number (FN),and three QTL,SSR markers (Xgwm 577,Xwmc276,Xwmc273) of LMA gene. [Result] Results suggested that LMA was controlled by a single,and the three SSR markers seemed to be not efficient to test LMA gene in this RILS. LMA was an important factor on FN,meanwhile FN was also affected by other factors. [Conclusion] The study could provide references for the breed of quality wheat.     

Comparison between facemask and laryngeal mask airway in rabbits during isoflurane anesthesia

OBJECTIVE: To determine whether a laryngeal mask airway (LMA) provides a better airway than a facemask in spontaneously breathing anesthetized rabbits, and to test if it can be used for mechanically controlled ventilation. STUDY DESIGN: Randomized prospective experimental trial. ANIMALS: Sixteen young, healthy, specific pathogen-free Giant Flemish cross Chinchilla rabbits (10 females and 6 males) weighing 4.1 +/- 0.8 kg. METHODS: Rabbits were assigned randomly to one of three treatment groups: facemask with spontaneous ventilation (FM-SV; n = 5), LMA with spontaneous ventilation (LMA-SV; n = 5), and LMA with controlled ventilation (LMA-CV; n = 6). In dorsal recumbency, and at 2.3% end-tidal isoflurane concentration, Fé isoflurane, Fi isoflurane, partial pressure of expired isoflurane (PECO(2)), partial pressure of inspired carbon dioxide (PiCO(2)), heart rate, respiratory rate, minute volume, arterial oxygen tensions (PaO(2)), arterial carbon dioxide tensions (PaCO(2)), arterial pH (pH(a)), arterial standard base excess (SBE(a)) values were measured for 120 minutes. Results Two individuals in the FM-SV group had PaCO(2) > 100 mm Hg. One rabbit in the FM-SV had PaO(2) < 80 mm Hg. All FM-SV rabbits showed signs of airway obstruction, and two were withdrawn from the study at 45 and 90 minutes, respectively, because cyanosis was observed. No signs of airway obstruction were observed in either LMA group. Four rabbits in the LMA-CV group developed gastric tympanism, one of which refluxed gastric contents after 110 minutes. There were no differences between FM-SV and LMA-SV in any variable tested. PaCO(2) and PECO(2) were decreased, while PaO(2) and minute volume were increased in the LMA-CV group compared to the LMA-SV group. CONCLUSIONS: An LMA provided a better airway than a facemask during spontaneous breathing in rabbits, as the use of a facemask was associated with hypercapnia and low partial pressures of oxygen. Although an LMA can be used for intermittent positive pressure ventilation (IPPV), gastric tympanism may develop, especially at a peak inspiratory pressure of 14 cm H(2)O. CLINICAL RELEVANCE: The LMA can be used in rabbits but further work is needed before it is applied routinely.     

桂花叶片SPAD、叶绿素含量和比叶重特征

对金桂(O.fragrans var.thunbergii)和四季桂(O.fragrans var.semperflorens)叶片的比叶重、叶绿素含量、叶片SPAD值以及养分含量进行了研究,探讨了SPAD值与叶绿素含量的相关性。结果表明,金桂叶片叶绿素a/b值低于四季桂,其他指标均高于四季桂;不同植株四季桂叶片的各指标含量均无显著差异(P0.05),而金桂叶片的叶绿素a、叶绿素b、叶绿素总量(a+b)、类胡萝卜素含量在不同植株间差异显著(P0.05);四季桂(16.32 cm2)的叶面积要小于金桂(35.37 cm2),而四季桂的比叶重却略大于金桂,比叶重均值分别为18.53和16.62 mg·cm-2;四季桂和金桂叶片均偏酸性;四季桂叶片磷含量、镁含量均高于金桂,钙含量、钾含量分别小于金桂;叶片叶绿素总含量与SPAD值呈显著相关。在城市热岛现象突出的情况下,金桂的叶面积大,适应强光能力强,更适合在城市绿化中推广使用。     

干旱半干旱区降水量梯度下植物群落的叶、茎属性特征

通过对沿年均降水量减少的兰州、白银、景泰和临泽4个试验点不同科属植物进行野外调查与室内分析,试图明确干旱区降水量梯度下植物叶、茎属性〔比叶重(LMA)、单位面积氮含量(Narea)和单位面积叶绿素含量(Chlarea)〕的变化并探讨其对渐进干旱胁迫的适应规律。结果表明:降雨量梯度下叶、茎利用不同属性特征应对干旱胁迫,LMA和Narea含量随干旱胁迫的加剧而增大,Chlarea含量随干旱胁迫的加剧而降低,这在一定程度上体现了研究区域植物对干旱胁迫加强的适应规律。另外随年均降水量的减少,临泽、景泰、白银、兰州其物种的绿色茎枝/叶生物量比依次减小。即随干旱胁迫的加剧,干旱区植物绿色茎枝与叶片生物量的比例逐渐增大。