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1.
一般认为我国南方栗仅宜于菜用,加工极易开瓣和糊化,经过几年的筛选和加工试剂,永荆3号品种可生产B-E级标准的糖水栗子罐头。  相似文献   
2.
分析了造成母猪繁殖能力低的因素主要表现为乏情期长和产仔数低,其次是不孕,流产,产弱仔,产木乃伊胎及死胎等。而繁殖障碍性疾病和饲养管理不当是突出的问题。提出了通过疾病控制和科学饲养来提高母猪繁殖能力的措施。  相似文献   
3.
猴头菌新菌株宁猴6号的选育初报   总被引:2,自引:0,他引:2  
采用多孢分离技术产生多个新组合 ,经驯化筛选获得猴头新菌株宁猴 6号 ,宁猴 6号为适合用针叶林木屑物料栽培的新菌株。生物学特性表明 :猴头菌宁猴 6号菌丝生长适温 2 5~ 2 8℃ ,子实体生长适温 15~2 0℃ ,菌丝生长期短 ,36~ 4 0d长满瓶底 ,栽培袋在常温下培养 4 3~ 5 0d菌丝满袋。室内栽培生物学效率达5 6 .0 0 % ,室外栽培生物学效率达 6 1.4 0 % ,子实体中型匀称近球型 ,柄短或无柄 ,刺长 0 .9~ 2 .2cm。宁猴 6号不仅适于阔叶木屑栽培 ,最突出的是适应针叶林木屑栽培  相似文献   
4.
沙棘叶子中黄酮的分离与鉴定   总被引:13,自引:6,他引:7  
阮栋梁  王晖  李和 《沙棘》2002,15(4):32-34
利用硅胶柱和葡聚糖聚胶柱层析,从沙棘叶子中分离并鉴定出黄酮类成分,并对其结构进行了结构鉴定。  相似文献   
5.
利用硅胶柱和葡聚糖凝胶柱层析,从沙棘叶子中分离并鉴定出黄酮类成分,进一步分离得到4,4′-二羟基-2′-甲氧基查耳酮,并对其结构进行了结构鉴定。  相似文献   
6.
7.
AIM:To compare the effects of carvedilol, cilazapril and their combination on left ventricular remodeling(LVRM) after acute myocardial infarction(AMI) in rats. METHODS: Twenty-four hours after AMI operation, 100 surviving rats were randomly assigned to: ①AMI control(n= 25), ②AMI+carvedilol(1 mg·kg-1 ·d-1, n= 25)(C1), ③AMI+cilazapril(1 mg·kg-1 ·d-1, n= 25)(Z1), and ④ AMI+combination(n= 25) groups. Sham-operated group(n= 17) were selected randomly. After 4 weeks of therapy with the drugs gastric gavage, hemodynamic and pathological studies were performed. RESULTS: There were no significant differences in MI size among the four AMI groups(all P> 0.05) Left ventricular(LV) end diastolic pressure(LVEDP), volume(LVV), weight(LVW) and septal thickness(STh) were all higher and left ventricular pressure maximal rate of rise and fall(±d p /d t) were lower(all P< 0.01) in AMI group than sham-operated group. The LVEDP, LVV, LVW and STh were all lower and ±dp /dt were higher in Z1, C1, and combination groups than those in AMI group(P< 0.05, P< 0.01), with LVEDP and STh were more lower in the combination group than in the two monotherapy group(P< 0.05, P< 0.01), but there were no significant differences in other variables among the three therapy groups. CONCLUSION: Carvedilol, cilazapril and their combination all can prevent from LVRM after AMI in rats, improve hemodynamics and LV function, with the combination superior.  相似文献   
8.
山楂叶螨抗药性及混配增效作用   总被引:4,自引:2,他引:4  
采用载玻片浸渍法测定了山西省忻州、晋中、运城地区山楂叶螨种群对9种杀螨剂的抗药性水平.测定结果表明:忻州地区种群对甲氰菊酯和三氯杀螨醇表现中抗,抗性指数FR分别为17.79和31.93倍,对水胺硫磷和毒死蜱表现低抗,FR值分别为7.74和5.35倍;晋中地区种群对水胺硫磷、甲氰菊酯和三氯杀螨醇均表现中抗,FR值为22.42~33.00倍,而运城地区种群对这3种药剂产生了高抗,FR值分别为135.05、41.53和1714.01倍;运城地区种群对毒死蜱表现中抗,FR值为34.49倍;晋中和运城地区种群对双甲脒表现低抗,FR值分别为5.15和6.89倍;3个种群对阿维菌素、苯丁锡、三唑锡和四螨嗪仍相对敏感.混配增效作用测定结果表明,阿维菌素与甲氰菊酯1:20、1:10、1:5组合以及阿维菌素与三氯杀螨醇1:20、1:10组合均具有明显增效作用,共毒系数为189.63~363.30,其中阿维菌素与甲氰菊酯1:20和1:10组合以及阿维菌素与三氯杀螨醇1:20组合是比较理想的混配组合.  相似文献   
9.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.  相似文献   
10.
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 (Ito), delayed rectifier potassium current (IK) and inward rectifier potassium current (IK1) 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, Ito, IK and IK1 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 Ito, IK,tail and IK1 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 Ito, IK,tail and IK1 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.  相似文献   
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