桑树新品种育71-1的育成初报

育71—1是通过杂交、单株选择、株系选择和品比试验等一系列选育程序,培育成功的新桑树品种。其主要经济特性与湖桑32号相比,发芽期早2—3天,发芽率提高28.7％,产叶量提高47.7％,叶质较优,丝质成绩相仿;抗旱性较强。目前,正在江苏的海安、溧阳及山东等部分地区试种。     

日光温室内外金太阳杏光合特性的比较研究

为了探明杏对设施栽培的生理反应,对日光温室内外金太阳杏光合特性进行了比较研究。结果表明,日光温室栽培条件下,金太阳杏单位重量叶片的叶绿素含量增加;光(CO2)饱和点和光(CO2)补偿点降低鸦露地晴天净光合速率Pn日变化呈明显的双峰曲线,温室内也呈双峰线,但双峰出现原因不同。并且研究了影响光合作用的主要生态因子及变化规律,发现净光合速率与胞间CO2浓度、蒸腾作用、气温、叶温、光合有效辐射等因子相关。     

苹果渣替代麦麸饲喂雏鸡效果试验

选用400只商品代尼克红母雏,随机分为4组,每组100只,设5个重复,每个重复 20只。试验组日粮分别由基础日粮和用风干未发酵苹果渣粉、半干发酵苹果渣粉、膜发酵苹果 渣粉分别替代基础日粮中5％的麸皮。试期为6周。结果显示,添加半干发酵苹果渣粉组和膜 发酵苹果渣粉组试鸡6周龄平均体重及日增重显著高于喂基础日粮的对照组和风干未发酵苹 果渣粉组(P<0．05),喂基础日粮的对照组略高于风干未发酵苹果渣粉组,差异不显著 (P>0．05)。表明发酵苹果渣粉对雏鸡生长发育有显著的促进效果。     

Effect of moxonidine hydrochloride on left ventricular hypertrophy in spontaneously hypertensive rats

AIM:To investate the effect of domestric moxonidine hydrochloride on myocardium fibrosis and coronary artery microvascular structure in left ventricular hypertrophy of spontaneously hypertensive rats(SHR).METHODS:30 male SHR, aged 20 weeks, were divided into group Mox+SHR, Cap+SHR and SHR randomly (10 in each group). 10 age and sex-mached sprauge-dawley rats were designed as normal control(NC). At the end of 13 weeks, left ventricular wight/body weight ratio(LVW/BW), collagen volume fraction(CVF) and standardized perivascular collagen area(PVCA) as well as intramyocardial arterial average medial thickness (AMT) were determined.RESULTS:LVW/BW, CVF, PVCA and AMT in group Mox+SHR were lower significantly than that in group SHR, respectively.CONCLUSION:Long-term antihypertensive treatment with moxonidine hydrochloride reduces myocardium fibrosis and improves impaired coronary artery microvascular structure in left ventricular hypertrophy.     

Mast cell tryptase and asthma

As an important mediator of allergic inflammation, mast cell tryptase is involved in the in duction of hypersensitivity, infiltration of inflammatory cel s and t issue remodeling in respiratory tract.The effects of tryptase inhibitors on the actions of tryptase show further the potential of tryptase in the pathogenesis of asthma and its inhibitors in the treatment of asthma.     

Effects of nitric oxide on hepatic encephalopathy in cirrhotic rats induced by LPS

AIM: To investigate the effects of nitric oxide (NO) on hepatic encephalopathy in cirrhotic rats induced by LPS. METHODS: The cirrhotic model of rats was established by complex pathogeny. Since the end of the 8 th week, the rats were intragastrically-infused with 0.9% salt, L-arginine(L-arg) and LNNA respectively for 2 weeks.The hepatic encephalopathy in cirrhotic rats were induced by 3 mg/kg LPS (ip) 4 hours before the rats were sacrificed. RESULTS: The normal behaviors and electroencephalograph were appeared in L-arg group. LNNA group showed hepatic encephalopathy. The content of NO₂^-/NO₃^- of brain tissue was markedly higher in L-arg group than LNNA group(P<0.05), but the content of histamine in brain tissue was lower in L-arg group than LNNA group(P<0.05). There was a negative correlation between the content of histamine in brain tissue and the content of NO₂^-/NO₃^- of brain tissue. CONCLUSION: NO can prevent hepatic encephalopathy in cirrhotic rats induced by LPS.     

Changes of intracellular potassium activity and membrane potential in guinea pig ventricular myocardium during superfusion with low sodium solutions and effects of low pH

AIM:To investigate the changes in intracellular potassium activity(aⁱK) and membrane potential(V_m) induced by low external sodium infusion (Low [Na]_o) and to detect the mechanisms involved and the relationship between aⁱK and V_m. METHODS:aⁱK and V_m were measured in infusion with different sodium concentrations using methods of convenient and ion selective microelectrodes in guinea pig ventricular myocardium. RESULTS:Low [Na]_o resulted in a decrease in aⁱK and an increase in V_m in a Na⁺ concentration-dependent manner.At the same time,contraction and resting potential increased, and action potential duration decreased markedly,but action potential amplitude was not affected. A change of the pH from 7.4 to 7.0 in low [Na]_o solution reduced the decrease in aⁱK, but did not affect the increase in V_m.CONCLUSION:A better linear relationship appeared between the changes in aⁱk and [Na]_o or in V_m and [Na]_o,while during each low [Na]_o the change in both aⁱK or V_m may reach a new balance level.     

利用RT-PCR检测库尔勒香梨苹果茎痘病毒的研究

 以库尔勒香梨新鲜、冷藏、冷冻叶片和皮层为材料,对提取双链RNA (dsRNA)的2种方法和提取总RNA的3种方法进行了分析比较,并对总RNA的提取方法进行了改进,获得了纯度较高、完整性较好的dsRNA和总RNA,在此基础上进行了反转录(RT)和PCR扩增。在国内首次完成了对苹果茎痘病毒(ASPV)的RT-PCR检测,建立了ASPV有效RT-PCR反应体系。用此体系扩增到ASPV一个长约316 bp的片段。实验表明以dsRNA和总RNA为模板均能成功进行RT-PCR检测,且dsRNA优于总RNA。     

Changes of potassium currents in rabbit ventricle with healed myocardial infarction

AIM: To elucidate the mechanism of arrhythmia in healed myocardial infarction (HMI), and to investigate the changes of action potential duration (APD),transient outward potassium current (I_to), delayed rectifier potassium current (I_K) and inward rectifier potassium current (I_K1) of left ventricular myocytes in noninfarcted zone of HMI. METHODS: 12 rabbits were randomly assigned in two groups: HMI group (thoracotomy and ligation of the circumflex coronary); sham-operated group (thoracotomy but no conorary ligation). 3 months after operation, whole cell patch clamp technique was used to record APD, I_to, I_K and I_K1 of ventricular myocytes in non-infarcted zone. RESULTS: Membrane capacitance was larger in HMI group than that in sham-operated group. Action potential duration was lengthened significantly in HMI group and early after depolarization (EAD) appeared in HMI group. The densities of I_to, I_K,tail and I_K1 were reduced significantly in HMI group (P<0.01), from (6.72±0.42) pA/pF, (1.54±0.13) pA/pF and (25.6±2.6) pA/pF in Sham-operated group to (4.03±0.33) pA/pF, (1.14±0.11) pA/pF and (17.6±2.3) pA/pF, respectively. CONCLUSION: The reduced densities of I_to, I_K,tail and I_K1 in ventricular myocytes of non-infarcted zone in HMI are responsible for the prolongation of APD and the presentation of EAD, which play important roles in the malignant arrhythmia of HMI.     

以Taichung29为背景的小麦抗条锈病近等基因系转育进展

自1988年起,系统开展了以Taichung29为背景的小麦抗条锈病近等基因系转育及其基础性研究。采用回交法和系谱法相结合的转育方法,以春性品种Taichung29为轮回亲本作母本,分别与25个抗性供体即中国小麦条锈病菌鉴别寄主和国际上重要的抗条锈基因载体品种杂交、回交和自交。通过基因推导分析、单体分析和SSR标记技术检测目的基因,选育抗条锈近等基因系,现已获得重要进展,成功选育出8个以Taichung29为背景的抗条锈病单基因近等基因系,即Taichung29*6／Yr1、Taichung29*6／Yr2、Taichung29*6／Yr5、Taichung29*6／Yr7、Taichung29*6/Yr9、Taichung29*6／Yr10、Taichung29*6/YrSpP、Taichung29*6/YrKy2。另有9个组合转育获得343个抗性稳定株系,正检测其目的基因,3个组合转至BC₆F₃,自交纯合筛选抗性稳定株系,5个组合转至BC₅,继续回交转育。