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1.
为探讨绿色木霉固体发酵产孢子的最佳发酵培养基。运用响应面法设计试验,筛选出主要影响因子碳酸钙、硫酸铵及氯化锰,以孢子量为响应值建立二次回归方程,并借助Design Expert 8.0.6软件进行分析数据并确定优化条件。结果表明,在温度28℃,接种量15%,料水比1:0.70的培养条件下发酵7天,孢子量为8.505×109CFU/g。通过优化,最终确定最佳发酵配方为:麸皮(过40目筛)50%,稻壳粉(过20目筛)30%,玉米粉(过80目筛)20%,硫酸铵1.08%,黄豆饼粉2.00%,玉米浆干粉2.00%,碳酸钙0.55%,氯化锰0.37%,pH 6.0~7.0。该配方所用原料廉价易得,发酵水平高,为大规模工业化生产提供保障。  相似文献   
2.
按照普通植物种子的情况,推定灵芝孢子的结构有完全充满、部分充满、有大空隙和无种仁4种形式。为此,按照这4种形式分别说明了灵芝孢子受高等静压作用时,孢子壁的破坏方式和灵芝孢子有效成分的溶出方式。  相似文献   
3.
多架次作业植保无人机最小能耗航迹规划算法研究   总被引:8,自引:0,他引:8  
利用栅格法对工作区域进行划分,快速得到往复遍历式植保无人机的作业路径,在以作业架次数最少为约束条件的情况下,研究了一种多架次返航路线规划算法,合理地分配了各架次的喷药量和返航点,使无人机的工作总能耗最小,降低了无人机在非作业情况下无效消耗能量,提高了作业效率。仿真结果表明,在同等作业条件下,在一块210 m×200 m的矩形作业区域,采用本算法进行航迹规划,相比于仅以药液耗尽为返航依据的航迹规划,能耗节省率达到了12.89%,而且作业面积越大,能量节省效果越明显,通过田间对比试验,进一步证明了算法的可行性。  相似文献   
4.
为探索由银耳(Tremella fuciformis)子实体、菌丝体胶质化产生的双核酵母状孢子(FBMds)的萌发条件,研究比较了不同来源和不同浓度的香灰菌(Annuloypoxylon stygium)浸提液及不同来源银耳孢子发酵液对银耳Tr21 FBMds萌发率的影响。试验结果表明,香灰菌浸提液和银耳孢子发酵液均有不同程度促银耳Tr21FBMds萌发的作用。不同浓度香灰菌浸提液对FBMds萌发率的试验表明,在一定浓度范围内,高浓度香灰菌浸提液可显著提高银耳FBMds萌发率,最佳浓度为40%;在该浓度下,银耳Tr21的原伴生香灰菌HTW01-5的浸提液对FBMds萌发率作用高达30.34%。银耳孢子T30-CAS、Tr01、Tr21、T8225-CAS的发酵液虽能显著促进银耳Tr21 FBMds的萌发,但效果不如香灰菌浸提液明显。研究所得银耳菌丝为纯菌丝,可稳定传代,为进一步研究银耳二型态转变以及银耳新品种选育奠定了扎实基础。  相似文献   
5.
Epidemiology and control of Menangle virus in pigs   总被引:6,自引:0,他引:6  
OBJECTIVE: To describe the epidemiology and eradication of Menangle virus infection in pigs. DESIGN: Field observations and interventions, structured and unstructured serological surveys, prospective and cross-sectional serological studies and laboratory investigations. PROCEDURE: Serum samples were collected from pigs at a 2600-sow intensive piggery in New South Wales that experienced an outbreak of reproductive disease in 1997. Serum samples were also collected from piggeries that received pigs from or supplied pigs to the affected piggery and from other piggeries in Australia. Serum and tissue samples were collected from pigs at piggeries experiencing reproductive disease in New South Wales. Sera and faeces were collected from grey-headed flying foxes (Pteropus poliocephalus) in the region of the affected piggery. Serum samples were tested for neutralising antibodies against Menangle virus. Virus isolation was attempted from faeces. RESULTS: Following the outbreak of reproductive disease, sera from 96% of adult pigs at the affected piggery, including sows that produced affected litters, contained neutralising antibodies against Menangle virus. Neutralising antibodies were also detected in sera from 88% of finisher pigs at two piggeries receiving weaned pigs from the affected piggery. No evidence of Menangle virus infection was found in other piggeries in Australia. In cross-sectional studies at the affected piggery, colostral antibodies were undetectable in most pigs by 14 to 15 weeks of age. By slaughter age or entry to the breeding herd, 95% of pigs developed high antibody titres (> or = 128) against Menangle virus in the virus neutralisation test. Menangle virus was eradicated from the affected piggery following a program of serological testing and segregation. Neutralising antibodies against Menangle virus were also detected in P poliocephalus from two colonies in the vicinity of the affected piggery. Two piggery workers were infected with Menangle virus. There was no evidence of infection in cattle, sheep, birds, rodents, feral cats and a dog at the affected piggery. CONCLUSIONS: Serological evidence of infection with Menangle virus was detected in pigs at a piggery that had experienced reproductive disease, in pigs at two associated piggeries and in fruit bats in the region of the piggery. Two humans were infected. The mode of transmission between pigs is unknown, but spread by faecal or urinary excretion is postulated. This virus can be eradicated by the segregation of pigs into discrete age groups.  相似文献   
6.
The efficacy of chlorhexidine digluconate was determined against some strains of collected and clinically isolated bacteria and fungi. The efficacy was evaluated either by calculating a minimum inhibitory concentration (MIC) or by efficacy trials according to the guidelines of the European Committee for Standardization. The MIC values of chlorhexidine for Staphylococcus aureus, Microsporum gypseum, Microsporum canis and Trichophyton mentagrophytes were 0.625 g/ml, 12.5 g/ml, 50 g/ml and 6.25 g/ml, respectively. The in vitro efficacy of chlorhexidine was higher against ATCC strains of S. aureus and P. aeruginosa (0.5 mg/ml for 5 min and 0.5 mg/ml for 10 min, respectively) than against clinical isolates (0.5 mg/ml for 15 min and 1 mg/ml for 10 min, respectively). The antiseptic activity of aqueous solutions of chlorhexidine against spores of Bacillus subtilis, Bacillis sfericus and Clostridium perfringens required longer contact times than against the vegetative forms. Nevertheless, 5 mg/ml of chlorhexidine in water–ethanol 20:80 v/v was totally effective against the vegetative forms or spores of these microorganisms.  相似文献   
7.
Aeciospores in Uromyces fabae were found to be repeating spores and play an important role in pea rust outbreaks in the North Eastern Plain Zone (NEPZ) of India. Experiments conducted on pea rust from 2001 to 2004 revealed the dominance of aeciospores at all growth stages of pea in this region. Urediospore production was erratic and was only observed in a few samples of stems and tendrils (5–10%). Inoculation of pea plants either by aeciospores or urediospores resulted in the production of aeciospores. Production of aeciospores was observed at a temperature range of 10–25 °C, with a maximum at 25 ± 2 °C. Among the different growth stages of pea, the pod formation stage was highly susceptible and produced the maximum number (744) of aecidia/leaf at 20–25 °C. Significant effects of growth stages and temperature were also noticed for pustule number. Urediospore production mainly coincided with the senescence of the pea plants. Maximum germination (2%) of aeciospores was observed at 25 °C, whereas maximum urediospore germination (3.5%) was at 15 °C. Temperatures > 15 °C decreased urediospore germination. A relative humidity (RH) of 100% was favourable for aeciospore germination while 98% RH favoured urediospore germination. Typical histo-pathological behaviour of the aeciospores was observed.  相似文献   
8.
AIM: To investigate the effect of Ganoderma lucidum spores powder on the expression of insulin-like growth factor-1 (IGF-1), nuclear factor-κB (NF-κB) and apoptosis of nerve cells in rats with epilepsy established by pentetrazole. METHODS: The sub-eclampsia dosage of pentetrazole (PTZ) was used to make epilepsy model. Ganoderma lucidum spores powder group was given from stomach. The enduring time and latent period were recorded. The immune reactivity of IGF-1, NF-κB/P65 and apoptosis of nerve cells were measured with immunohistochemical staining and TUNEL method. RESULTS: In high power sight (×400), there were much more apoptosis cells in hippocampus and brain cortex of model group (18.80±2.13, 16.87±2.00) than those in control group (0.97±0.52, 0.58±0.25). The expressions of IGF-1, NF-κB in model group were higher than those in control group. Compared with model group, the latent period of Ganoderma lucidum spores powder group at the 17th, 21th, 25th days were longer (P<0.05, P<0.05, P<0.01, respectively).There were less apoptosis cells in hippocampus and brain cortex of Ganoderma lucidum spores powder group (12.30±2.46, 10.48±1.33) than those in model group. The expression of NF-κB/P65 in Ganoderma lucidum spores powder group was lower than that in model group, but the immune reactivity of IGF-1 increased more distinctly in Ganoderma lucidum spores powder group than that in model group. CONCLUSION: IGF-1, NF-κB and apoptosis of nerve cells may have play a role in occurrence and development of PTZ-induced epilepsy. Ganoderma lucidum spores powder can suppress expression of NF-κB strongly, and facilitate the immune reactivity of IGF-1, which may be one of the mechanisms by which Ganoderma lucidum spores powder restrains the apoptosis of nerve cells caused by epilepsy to prevent the damages of nerve cells.  相似文献   
9.
1992~1994年在玉溪市刺桐关林区对云南松纵坑切梢小蠹成虫进行了系统的调查。据系统观测,成虫梢转干历期约143天;干转梢历期约为129天;梢转干的高峰期为每年的1月24日~2月10日,计18天,期间累计成虫数占总虫数的66.65%;干转梢高峰为每年的5月5~25日,计21天,期间累计成虫数占总虫数的64.56%。为便于监测测报,对成虫梢转干、干转梢过程中当地林木相应的物候期进行了观察  相似文献   
10.
各种锅炉消烟除尘设备都有自己的使用范围,本文主要介绍了供暖锅炉在消烟除尘选用中应考虑的问题,阐明选用消烟除尘设备时要充分了解其技术范围及其经济性能。  相似文献   
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