银杏营养贮藏蛋白质的细胞学研究

采用透射电子显微技术,对银杏的末端小枝和根中贮藏蛋白质细胞进行了超微结构的观察,研究结果表明:银杏营养贮藏蛋白质主要在枝条和根次生韧皮部的韧皮薄壁细胞和韧皮射线细胞中积累;液泡中的蛋白质主要以絮状、不规则块状、颗粒状和均一细沙状的形式存在;落叶期,银杏枝条贮藏蛋白质大量积累。2月底3月初,随着芽的萌动和新梢的生长,枝条中贮藏蛋白质首先被动用,根中的贮藏蛋白质积累和动用都晚于枝条。5月份,新梢中也开始积累贮藏蛋白质;内质网、高尔基体、线粒体与贮藏蛋白质的降解过程有关。     

ABA对花生胚离体发育的调节

实验结果表明，ＡＢＡ使花生离休胚处于胚性状态、抑制早萌并继续发育，ＡＢＡ的作用与其浓度有关。ＡＢＡ促进贮藏蛋白的合成，这种调控作用与胚的发育阶段有关。ＡＢＡ也促进了花生胚热稳定蛋白的合成和累积．     

Improvement of the emulsifying properties of porcine sarcoplasmic proteins with a low-molecular weight surfactant by the two-step emulsification method

The emulsifying properties of porcine sarcoplasmic protein (SP) with or without low-molecular weight surfactants were examined. The emulsifying activity (EA) of SP was weaker than that of sodium caseinate (CA), blood plasma (BP) and whey protein isolates at a protein concentration of 0.5–3%. Sodium chloride decreased the EA of SP. The EA of SP was about one quarter that of CA in the presence of 3% sodium chloride. As homogenization time increased, the EAs of SP and BP decreased. The EA of SP was not influenced by sucrose stearate ester (SE) with a hydrophilic-lipophilic balance (HLB) value of 16 (SE-16) but was decreased by those with HLB values of 5 and 1. Low-molecular weight surfactants such as SE-16, Tween 80 and sodium cholate improved the EA of SP with the two-step emulsification method: corn oil was previously emulsified with the surfactant before addition of SP and homogenization. In the case of the addition of SE-16 as primary emulsifier, the EA was about twice as high as that of SP alone. The same effect was shown in the emulsions formed by CA and soy protein isolate. These results indicate that the emulsifying properties of meat protein would be improved by the addition of a low-molecular weight surfactant in a two-step emulsification.     

猪繁殖与呼吸综合征病毒单克隆抗体的研究进展

单克隆抗体在兽医领域的应用价值越来越受到研究人员的重视。本文概述了近年来猪繁殖与呼吸综合征病毒（PRRSV）结构蛋白单克隆抗体的研究概况，以及它们在该病病毒分子生物学研究中的应用。     

The solubilization of myofibrillar proteins of vertebrate skeletal muscle in water

Myofibrillar proteins of vertebrate skeletal muscles are insoluble in solutions of ionic strength that approximate physiological conditions. We established a method to solubilize more than 80% of chicken breast muscle myofibrillar proteins in water for the use of meat as a source of food protein. SDS‐polyacrylamide gel electrophoretic patterns of water‐soluble myofibrillar proteins demonstrated that all identified myofibrillar proteins except connectin/titin were soluble in water. A part of α‐actinin was released from myofibrils by repeated washing with 2.5 mmol/L NaCl and 5 mmol/L L‐histidine solution, and subsequent destruction of connectin/titin in washed myofibrils by ultrasonication resulted in solubilization of a large fraction of chicken breast muscle myofibrillar proteins in water. Myofibrillar proteins of chicken leg, pork loin, beef shoulder loin, and lamb were also solubilized in water using this procedure.     

感染柔嫩艾美尔球虫的雏鸡血清蛋白醋膜电泳分析

用E .tenella卵囊感染雏鸡 ,通过醋酸纤维薄膜电泳检测 5种血清蛋白百分含量的变化。分别在感染后 3d和 7d进行采血检测。结果如下 :试验组的白蛋白 (% )在感染后 7d显著低于对照组 (P <0 0 5 ) ;试验组的α1 球蛋白 (% )在感染后 7d比在3d显著下降 (P <0 0 1) ;试验组的γ球蛋白 (% )在感染后 7d极显著高于 3d和对照组 (P <0 0 1)。α2 球蛋白 (% )和β球蛋白(% )在组间和组内无明显差异     

Influence of mitochondrial deficiency on expression of microtubule-associated proteins in primary cultured hippocampal neurons of neonatal rats

AIM: In order to study the relationship between mitochondrial deficiency and Alzheimer's disease(AD), we used sodium azide, a specific inhibitor of cytochrome C oxidase (COX), to develop a cell model of mitochondrial complex IV deficiency and investigated the impairment of microtubules and microtubule-associated proteins. METHODS: Primary cultured hippocampal neurons of hewborn rats were exposed to sodium azidethen cell viability was measured by MTT method; cell morphology, immunofluorecence-stained cellular microtubules and microtubule-associated proteins were observed by confocal microscopy. RESULTS: Primary cultured hippocampal neurons were exposed to 8-128 mmol/L sodium azide for 3-24 h, MTT absorbance decreased dose-and time-dependently. Exposed to 64 mmol/L sodium azide for 6 h, the processes of cells retracted, synapses disappeared, axons were shortened under contrast microscope. Meanwhile, microtubles were disassembled and became disorderly, the expression of microtubule-associated proteins were also reduced especially in the processes observed by confocal microscopy. CONCLUSION: Sodium azide inhibits the assembly and polymerization of tubulin in microtubules which may be reduced by low expression of microtubule-associated proteins in nerve cells. The damage of axons induced by microtubule collapse further blocks the intercellular signal transduction and intracellular material transportation which are important causes in cell death.     

Alterations of cardiac sympathetic norepinephrine transporter expression in rats with volume overload

AIM: To determine the alterations of myocardial 1-adrenergic receptor (1-AR) and cardiac sympathetic norepinephrine transporter (NET) mRNA expression, which is upstream modulator of 1-AR, in rats with longterm volume overload (VOL). METHODS: Left ventricular systolic (LVSP) and end diastolic pressure (LVEDP) of rats with VOL induced by aortacaval fistula operation and control group were measured at 314,30and 60d after the operation, the mRNA at the time points was measured by RT-PCR and Northern blot analysis and quantified by densitometry. RESULTS: The cardiac sympathetic NET specific expression is in the cardiac sympathetic ganglia. Be compared with the control group, LVSP of VOL rats decreased most dramatically by 24% (P<0.05) at 3 d, after that LSVP increased gradually and were higher than control group at 60d. LVEDP increased initially compared with the control (P<0.05), the latter recovered to the control levels. RT-PCR and Northern blot showed that in VOL rats the NET mRNA did not decreased significantly from 3to 30d, and decreased remarkably at 60d after the operation (P<0.05). The pattern of 1-AR mRNA expression were similar to the NET. CONCLUSION: The results suggest decreased levels of NET mRNA may contribute to cardiac sympathetic dysfunction in heart failure due to longterm VOL, which may lead to decreased myocardial 1-AR mRNA. We conclude that the normal NET mRNA expression may play a critical role to maintain sensitivity of 1-AR to adrenergic stimuli and cardiac contractility.     

Agarose gel electrophoretic fractionation of serum proteins in adult cattle. II. A study of cows with different diseases.

In 283 dairy cows suffering from internal disorders the serum proteins were studied by agarose gel electrophoresis supplemented by total protein and albumin determinations. The clinical diagnoses could be grouped according to protein pattern. Group 1 (abomasal displacement and traumatic muscle injury) did not appreciably affect the serum protein concentrations and represented primarily non-inflammatory diseases or diseases of non-infectious origin. Group 2 (leukosis) occupied an exceptional position, with heavy lowering of albumin unaccompanied by a corresponding rise of total globulin. The γ-globulin concentration was significantly lowered. Group 3 (acute traumatic peritonitis) represented an acute inflammatory process with increase chiefly of the α-globulins, while the γ-globulin concentration was normal. Group 4 (chronic traumatic peritonitis, summer mastitis, chronic subclinical mastitis, chronic laminitis and polyarthritis, urinary tract infection, abscess, and sub-acute-chronic pneumonia) comprised diseases chiefly of chronic inflammatory character and with infectious origin. Especially characteristic was the heavy rise of globulins in general and of γ-globulin in particular. In most cases there was a large increase also of the α- and p-globulin fractions.     

Electrophoretic patterns of serum proteins in blue foxes with special reference to changes associated with nosematosis.

The serum proteins in 1 group of healthy breeders, 1 group of healthy pups and 4 groups of foxes suffering from various diseases were separated electrophoretically on cellulose acetate membranes. In most of the sera, the proteins were separated into 1 albumin fraction and 5 globulin fractions designated alpha₁, alpha₂, alpha₃, beta and gamma. The mean concentrations of the total proteins and the various serum fractions in the disease groups were compared statistically with the mean values of the normal groups.A nosematosis group was characterized by a distinct hypergammaglobulinaemia together with an increase in the total protein — and a decrease in the albumin concentrations. However, in 2 cubs recovering from nosematosis the hypergammaglobulinaemia was shown to be reversible.In a feed intoxication group the concentration of albumin was found to be lower and the alpha₃-globulin higher than the corresponding values in the healthy group. A virus hepatitis group was characterized by a decrease in the concentrations of albumin and beta-globulin and an increase in the alpha₁- and alpha₃-globulins. In the toxoplasmosis group the total protein and alpha₁- and alpha₃-globulins showed concentrations below the normal values.