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The role of bacilli in cocoa fermentation is not well known. Their potential of production of pectinolytic enzymes during this process was evaluated. Bacillus growth was monitored and pectinolytic strains were screened for their use of pectin as sole carbon source. Effects of cocoa fermentation parameters susceptible to influence on enzyme production were analysed. Among 98 strains isolated, 90 were positive for pectin degradation and 80% of them presented detectable pectinolytic activities in submerged fermentation. Forty-eight strains produced polygalacturonase (PG), 47 yielded pectin lyase (PL) and 23 strains produced both enzymes. Bacilli growth was not significantly affected during fermentation. PL production was favoured by galactose, lactose, glucose as sugars, and arginine, glutamine, cysteine and ammonium sulphate as nitrogen compounds. Pectin at low concentration (0.05%) and iron stimulated PL production. It was strongly repressed by galacturonic acid (1%), and negatively affected by nitrogen starvation, zinc and temperatures above 45°C. PL yield was very weak below pH 4.0 and in anaerobic conditions. PG production was weakened by sucrose and cation depletion. It was increased slightly by cysteine, ammonium nitrate and nitrogen starvation and significantly above 40°C. PG synthesis was not affected by acidic pH (3.0–6.0) or oxygen availability. As fermentation products, lactate and acetate lowered the production of both enzymes while ethanol had no effect. The high proportion of pectinolytic producers among the strains studied and analysis of factors influencing pectinolytic enzymes production, suggest that Bacillus sp. is liable to produce at least one enzyme during cocoa fermentation.  相似文献   
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The COL1A2 gene is one of the two genes encoding for the polypeptides of type I collagen, that represent the major constituent of skin, bone, tendons, ligaments, blood vessels, dentin, and many interstitial tissues. The COL1A2 gene deletion polymorphism has been considered as an informative anthropological marker for describing geographically distinct human populations. Aim of the present study was to investigate the genetic variability at COL1A2 locus in two populations, one belonging to Ouangolodougou (n = 133), a village placed in Northern Ivory Coast, and one belonging to Lecco (n = 70), a village placed in a Northern Italy region called Lombardy. For each sampled population no data are available in literature. We reported, for the first time, the presence of the deleted allele among Ivorians (0.06), confirming the low deletion frequency of this polymorphism found in Sub Saharan Africa by other authors. For Italians, frequency analysis of this gene polymorphism (0.28 for the deleted allele) did not show any significant level of differentiation with respect to other Italian and European populations. The article is published in the original.  相似文献   
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IntroductionThe first and only Anger camera of Burkina Faso has been installed at the Yalgado Ouedraogo University hospital (CHU YO) in November 2011. The first clinical applications began in January 2012, 20 years after the training of the first nuclear physician of Burkina Faso. The department has opened with the cooperation of the International agency of atomic energy (IAEA) in the framework of a structured project. The objective of this study was to analyze the distribution of scintigraphic examinations performed in the nuclear medicine department, CHU YO, according to medical indications, during the first 6 months.MethodsThe examinations were performed from January 09, 2012 to 15 July 2012. All patients who underwent a scan in the nuclear medicine department were included in the study. The imaging device used was a Mediso? dual head camera installed in 2011. Tc 99m generator was delivered once per month by IBA? France. Cold kits had been delivering at the opening of the nuclear medicine department.ResultsSlightly more than half of the examinations have been performed in men (53.1%). June was the month that recorded the greatest number of examinations carried out (25.7%). Bone and thyroid scans represented 68.1% of nuclear medicine diagnostic procedures. Yalgado Ouedraogo University hospital represented more than half of the departments of origin of prescribers (60.2%). Most scans performed in the department of nuclear medicine were prescribed by internal medicine physicians (22.1%). Work-up for bone metastases in breast cancer was the first indication of bone scans (22.7%). Multinodular goiter (36.4%) and solitary nodules (36.4%) were the first indications of thyroid scintigraphy. Searching for stress-induced myocardial ischemia has been the reason for myocardial perfusion scintigraphy in more than half of the cases (53%). The study of separate renal function has been the commonest indication of renal scans (72.73%). Suspicion of pulmonary embolism was the only clinical indication for lung perfusion scans in the nuclear medicine department.ConclusionIn the future, this new department aims to develop by the extension of the supply of diagnostic examinations and the beginning of radionuclide therapy.  相似文献   
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许琴  曹娟  赵烨  印获  章旭  刘显章 《生物磁学》2013,(36):7085-7088
目的:探究尿毒症皮肤瘙瘁患者采取腹膜透析与血液透析治疗的临床效果,并为该病的临床治疗提供经验积累。方法:选取我院肾内科于2005年1月-2012年12月收治的52例尿毒症皮肤瘙痒患者,利用随机数字表法进行分组,分别设为研究组和对照组。其中对照组实施血液透析治疗,而研究组开展腹膜透析治疗。记录两组在治疗前和治疗后第8周末血生化客观指标及皮肤瘙痒程度,并做好对比。结果:两组在治疗前的皮肤瘙痒评分、β2-MG、PTH、p3,BUN、SCr值差异无统计学意义(P〉0.05);治疗后,研究组皮肤瘙瘁评分为(3.4±0.8)分,对照组为(5.8±0.9)分,差异有统计学意义(P〈0.05)。治疗后,研究组β2-MG、PTH及Ps.均低于对照组,差异有统计学意义(P〈0.05)。结论:尿毒症皮肤瘙痒患者的主要致敏因子为大中分子,采取腹膜透析能够有效清除大分子物质,进而达到瘙痒程度的有效改善。  相似文献   
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The chemical composition of 48 leaf oil samples isolated from individual plants of Cleistopholis patens (Benth .) Engl. et Diels harvested in four Ivoirian forests was investigated by GC‐FID (determination of retention indices), GC/MS, and 13C‐NMR analyses. The main components identified were β‐pinene (traces–59.1%), sabinene (traces–54.2%), (E)‐β‐caryophyllene (0.3–39.3%), linalool (0.1–38.5%), (E)‐β‐ocimene (0.1–33.2%), germacrene D (0.0–33.1%), α‐pinene (0.1–32.3%), and germacrene B (0–21.2%). The 48 oil compositions were submitted to hierarchical clustering and principal components analyses, which allowed the distinction of three groups within the oil samples. The oil composition of the major group (Group I, 33 samples) was dominated by (E)‐β‐caryophyllene and linalool. The oils of Group II (eight samples) contained mainly β‐pinene and α‐pinene, while those of Group III (seven samples) were dominated by sabinene, limonene, and β‐phellandrene. Moreover, the compositions of the Ivoirian C. patens leaf oils differed from those of Nigerian and Cameroonian origins.  相似文献   
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Miscanthus is a C4 bioenergy perennial crop characterized by its high potential yield. Our study aimed to compare the carbon storage capacities of Miscanthus sinensis (M. sinensis) with that of Miscanthus × giganteus (M. × giganteus) in field conditions in different types of soils in France. We set up a multi‐environment experimental network. On each trial, we tested two treatments: M. × giganteus established from rhizomes (Gr) and M. sinensis transplanted seedlings (Sp). We quantified the soil organic carbon (SOC) stock at equivalent soil mass for both genotypes in 2014 and 2019 and for two sampling depths: L1 (ca. 0–5 cm) and L1‐2 (ca. 0–30 cm). We also calculated the total and annual variation of the SOC stock and investigated factors that could explain the variation and the initial state of the SOC stock. ANOVAs were performed to compare the SOC stock, as well as the SOC stock variation rates across treatments and soil layers. Results showed that the soil bulk density did not vary significantly between 2014 and 2019 for both treatments (Gr and Sp). The SOC concentration (i.e. SOC expressed in g/kg) increased significantly between 2014 and 2019 in L1, whereas no significant evolution was found in L2 (ca. 5–30 cm). The SOC stock (i.e. SOC expressed in t/ha) increased significantly in the superficial layer L1 for M. × giganteus and M. sinensis, by 0.48 ± 0.41 and 0.54 ± 0.25 t ha?1 year?1 on average, respectively, although no significant change was detected in the layer L1‐2 for both genotypes. Moreover, SOC stocks in 2019 did not differ significantly between M. × giganteus and M. sinensis in the soil layers L1 and L1‐2. Lastly, our results showed that the initial SOC stock was significantly higher when miscanthus was grown after set‐aside than after annual crops.  相似文献   
59.
高婷  赵怀龙  刘萱  曹诚 《生物技术通讯》2011,22(6):806-808,891
目的:获得酶原形式的重组人甘露聚糖结合凝集素相关丝氨酸蛋白酶2(MASP2)。方法:在大肠杆菌中诱导表达重组人MASP2全长蛋白,包涵体裂解后,经复性、透析、浓缩、考马斯亮蓝染色、SDS-PAGE及Western印迹,鉴定纯化结果及酶活性。结果:复性后的MASP2蛋白经考马斯亮蓝染色未见杂带。自激活实验表明,当MASP2浓度在1μmool/L以下时,无论在4℃还是37℃,都能较稳定地保持酶原形式;蛋白浓度为3.5μmool/L时只能在4℃保持稳定,37℃发生自激活;蛋白浓度达到12μmool/L后,在4℃时已不能稳定存在。结论:获得了较纯的重组人MASP2蛋白,且具有自激活活性。  相似文献   
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变性高效液相色谱技术对创伤弧菌检测的研究   总被引:2,自引:0,他引:2  
应用PCR结合变性高效液相色谱技术对创伤弧菌进行检测,建立创伤弧菌快速准确的检测新方法。经过DHPLC分析条件优化,在DHPLC非变性温度下分析创伤弧菌特异性PCR扩增产物。同时进行方法特异性、灵敏度、重复性实验。实验结果表明所建立的创伤弧菌PCR-DHPLC检测方法特异性强、灵敏度高、重现性好、结果稳定可靠、检测时间短,检测低限可达到124 CFU/mL,是创伤弧菌快速检测的新技术。  相似文献   
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