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排序方式: 共有198条查询结果,搜索用时 15 毫秒
91.
A microbiological study was carried out on Baobab fermented seeds (Maari) obtained from 4 different production sites in Burkina Faso (Mansila, Toulfé, Ouagadougou and Gorgadji).A total of 390 representative isolates comprising 251 aerobic mesophilic bacteria (AMB) and 139 lactic acid bacteria (LAB) were isolated and identified to species level using a combination of pheno- and genotypic methods including conventional morphological analysis, carbohydrate fermentation profiling, rep-PCR ((GTG)5-fingerprinting) and 16S rRNA gene sequencing.The fermentation of Baobab seeds was initiated by the AMB identified as Bacillus subtilis (82% of AMB isolates) and Staphylococcus sciuri (18% of AMB isolates). No lactic acid bacteria were isolated at the beginning of the process. After 24 h fermentation time, Enterococcus faecium appeared in the fermenting seeds and remained until the end of the fermentation, as the predominant LAB.In Maari collected from retail outlets the AMB count ranged from 6.7 log10 CFU/g to 10 log10 CFU/g while the LAB load ranged from 4.4 log10 CFU/g to 9.9 log10 CFU/g. The AMB were identified as belonging to genus Bacillus (12 species), Staphylococcus (3 species) and one species of Aerococcus, Macrococcus, Leifsonia, Kurthia, Proteus, Acinetobacter and Globicatella, respectively. A putatively novel, previously undescribed Corynebacterium sp. was also found. E. faecium was the dominant LAB in all investigated retail samples except one sample dominated by Pediococcus acidilactici.  相似文献   
92.
Direct plating is an effective technique for isolation and enumeration of Campylobacters from a variety of sample types; however, distinguishing Campylobacters from non-Campylobacter contaminants that frequently grow on many existing agars is difficult. In this study, it was determined that exposing Campylobacters to low levels (200 mg/liter) of triphenyltetrazolium chloride (TTC) was not inhibitory to growth yet was sufficient to give a deep-red to magenta color to the colonies. The new agars (Campy-Line agar [CLAI and Campy-Line blood agar [CLBA]) are translucent. The contrast of deep-red colonies on a translucent background greatly facilitates Campylobacter isolation and makes enumeration on light boxes or by electronic means possible. Direct plating of broiler carcass rinse samples (n = 20) was compared on Campy-Cefex agar and CLA. Recovery of Campylobacter populations was not significantly different between the agars (P < 0.05); however, enumeration was much less labor intensive with the CLA. No contaminants were observed on the CLA, whereas the Cefex agar supported the growth of approximately 14 contaminating (non-Campylobacter) CFU/ml. In a separate trial, recovery of Campylobacters from carcass rinses (n = 25) was similarly compared on Cefex, CLA, and CLBA. Again, recovery of Campylobacters was not significantly different between the agars (Pearson correlation coefficient = 0.988), whereas about nine contaminating (non-Campylobacter) CFU/ml were observed on Cefex agar and none on CLA or CLBA. Although some contaminants can still grow on CLA and CLBA and can present red colonies, most of these contaminants are easily distinguished from Campylobacter by differences in colony morphology.  相似文献   
93.
王振东 《真空》2000,(1):32-33
本文介绍用C200H可编程控制器实现ITO透明导电玻璃生产线的自动控制,实现对各系统的高度,自动,手动的控制,实现了对各系统的故障诊断报警。该控制系统可靠性,功能强,查找故障方便。  相似文献   
94.
95.
With increasingly more stringent requirements on steel quality and productivity in uphill teeming production, it is vital to attain more desirable fluid flow conditions in the filling of the mould. In this investigation, physical and mathematical modelling was carried out to study the effects of nozzle type and utilization of a swirl generator in the inlet nozzle on the flow pattern in the ingot mould during the initial filling period. Specific focus was on the effects on the resultant hump and axial velocities. Three cases were considered: 1) a straight nozzle, 2) a divergent nozzle, and 3) a divergent nozzle combined with a swirl generator. It was found that usage of the divergent nozzle, compared to the straight nozzle, resulted in a smaller hump and lower axial velocities in the bath. For the combination of divergent nozzle and swirl generator, these findings were even more pronounced, with the hump practically eliminated, and the axial velocities, as well as the turbulence at the meniscus, significantly lower. The findings of the study suggest that a divergent nozzle combined with a swirling flow generated in the nozzle could be used in the up‐hill teeming process in purpose to get calmer initial filling conditions.  相似文献   
96.
97.
Few studies investigate gambling problems at the symptom level; even fewer investigate how symptom patterns change throughout the course of a gambling disorder. The current study utilized the National Epidemiological Survey on Alcohol and Related Conditions (NESARC; Grant et al., 2004) to investigate how the specific symptoms of disordered gambling relate to its severity and course. Results demonstrated that symptom patterns and stability changed as the number of symptoms endorsed increased. Symptom patterns varied considerably from prior to past year (PPY) to past year (PY) timeframes. Certain symptoms were more stable than others and held predictive value as markers of emerging pathological gambling (PG). In particular, gambling to escape problems was one of the most stable symptoms and also predictive of progression to PG; reliance on others to support gambling was predictive of progression to PG among participants at-risk for PG. The differential diagnostic value of various reported symptoms, as well as their lack of stability, has implications for both researchers and clinicians. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
Livres reçus     
Maral  Bousquet  Veret  Derfler  Deweze  Bouche  Foray  Freeman  Hawkes  Lunven  Vedel  Gomez  Bichon 《电信纪事》1993,48(9-10):530-531
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99.
During recent decades the number of operations for peptic ulcer has decreased significantly. The incidence of operations for peptic ulcer or related complications during the period 1975-89 in persons older than 15 years was investigated in the Nord-Tr?ndelag region of Norway, with a population of approximately 100,000. The number of elective surgical procedures decreased by 72% from 1975 to 1989. The greatest reduction was found for duodenal ulcers. The incidence of acute operations decreased by 35%. The main reason was fewer surgical interventions in patients with haemorrhage, since the number of operations for perforation remained almost constant during the period of 15 years. The reduction in surgical treatment can be explained mainly by the introduction of new H2-antagonists in the seventies, leading to more successful pharmacological treatment of peptic ulcer.  相似文献   
100.
激光对蚕豆幼苗紫外线-B辐射损伤的防护作用   总被引:14,自引:3,他引:11  
用不同剂量的He Ne激光和CO2 激光辐射蚕豆 (ViciafabaL .)种子胚 ,对其幼苗进行丙二醛 (MDA)和抗坏血酸 (AsA)含量测定。结果发现He Ne激光的效果优于CO2 激光 ;He Ne激光的最佳辐射剂量为 5 4 3mW·mm-2 ,最佳辐射时间为 5min。先用He Ne激光辐射蚕豆种子 ,待其长至幼苗时 ,在光背景 (PAR) 70 μmol·m-2 ·s-1条件下 ,用 3 0 3kJ·m-2 UV B照射 7h/d ,然后对其超氧化物歧化酶 (SOD) ,过氧化物酶 (POD) ,过氧化氢酶(CAT)酶活性以及同工酶谱进行测定。结果发现 ,He Ne激光辐射可提高SOD ,POD ,CAT酶活性 ;改变SOD ,CAT同工酶谱。从而说明 ,激光对UV B辐射损伤植物具有一定的防护作用。  相似文献   
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