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31.
This study shows that the oxyanion tellurite TeO3(2-) can be used as a tool to detect and quantify the release in soil microcosms of Pseudomonas pseudoalcaligenes KF707, a strain spontaneously resistant to tellurite with a minimal inhibitory concentration (MIC) of 150 microg ml(-1). KF707 cells which carry the genes for degradation of a wide range of polychlorinated biphenyl congeners (PCBs) were used for inoculation of laboratory microcosms prepared with two different PCB-contaminated soils (Ci/s and Di/s) in the presence or absence of biphenyl as carbon source. In all microcosms supplemented with biphenyl, significant survival of strain KF707 was noted over a time period of 35 days; conversely, in microcosms containing Ci/s soil without biphenyl addition a rapid decrease in KF707 inoculated cells was observed. By comparing the number of inoculated KF707 cells with the number of indigenous bacteria growing on biphenyl (IBGB) of both Ci/s and Di/s microcosms, it could be concluded that the KF707/IBGB ratio is a relevant parameter in determining the fate of the added strain. The efficacy of potassium tellurite as a selective marker to monitor strain KF707 in laboratory microcosms was confirmed by ARDRA analyses of the 16S rDNA, while the isolated indigenous bacteria growing on biphenyl were identified as members of three different species of the genus Pseudomonas. We also report that in microcosms inoculated with KF707 cells in the absence of biphenyl, only low chlorinated biphenyls were degraded. 相似文献
32.
Fedi S Carnevali M Fava F Andracchio A Zappoli S Zannoni D 《Research in microbiology》2001,152(6):583-592
Fifteen bacterial strains using biphenyl as sole carbon and energy source, obtained from different positions and depths of a polychlorinated biphenyl (PCB)-contaminated area, were analyzed for their basic metabolic phenotypes and subjected to genomic DNA hybridization screening for the presence of well characterized bph operons such as those of Pseudomonas pseudoalcaligenes KF707 and Rhodococcus globerulus P6. Most of the isolates belonged to the gamma-subdivision (Pseudomonas stutzeri, P. plutida, P. fluorescens and Vibrio logei species) and to the beta-subdivision (genera Alcaligenes, Comamonas, Ralstonia) of the Proteobacteria. All the isolates were able to cometabolize different low chlorinated PCB congeners. Among the dichlorinated biphenyls tested, a lower degradation capacity was observed for the di-ortho substituted congeners, whereas high levels of degradation were observed for the di-meta and di-para isomers, whether they were chlorinated on one or on both rings. The PCB congeners nonsubstituted in the 2,3 or 2,3 and 3,4 positions were also degraded by most of the isolated strains, which were, however, unable to significantly metabolize PCBs with more than 3 chlorine atoms. Five of the isolated strains were also able to degrade some of the tri- and tetrachlorobiphenyls tested. Southern hybridization analysis showed a strong homology between four of the fifteen isolated strains and the bph operon obtained from P. pseudoalcaligenes strain KF707. Conversely, none of the isolates here examined showed homology with the bph operon of R. globerulus strain P6. In line with this, the KF707 bph probe strongly hybridized with DNA of a significant number of bacterial colonies obtained from selected locations in the contaminated area using biphenyl-supplemented minimal medium agar plates. 相似文献
33.
Arosio E De Marchi S Prior M Zannoni M Lucchese L Lechi A 《Journal of internal medicine》2000,247(4):471-478
OBJECTIVES: To assess the effects of cardiopulmonary baroreceptors on the haemodynamics of the humeral and common carotid arteries in patients suffering from peripheral artery disease (PAD) and to discover whether the stimulation of these receptors modifies the cutaneous microcirculation in the forearm. DESIGN: We studied a group of patients suffering from peripheral artery disease and two groups as controls. SETTING: Patients were examined at the ambulatory for Vascular Research, Division of Vascular Medicine and Rehabilitation, University of Verona. PATIENTS: We studied 15 patients with peripheral artery disease of the lower limbs at Fontaine stage II (group C), 10 free of arterial pathologies (group B) and 10 young people (group A). MAIN OUTCOME MEASURES: We subjected the patients to passive elevation of the legs and the trunk in a horizontal position with pressure monitoring and measurement of the calibre and flow in the brachial and common carotid arteries using a colourDoppler ultrasound. We also studied the cutaneous microcirculation with laserDoppler flowmetry. RESULTS: During the test, arterial pressure and cardiac frequency remained constant in group A, systolic pressure values showed a slight, but statistically significant increase in group B, whilst the increase in systolic pressure values at this stage was marked in group C. Diastolic pressure values and cardiac frequency remained unchanged in all groups. The calibre of the humeral artery increased in the control groups. Carotid resistance was unchanged in the three groups. Humeral resistance during the test decreased in the two control groups whilst it increased in group C. The number of perfusion units felt in the control groups; no variations in group C. CONCLUSIONS: Our study demonstrates, in patients with peripheral artery disease, a reduction in the activity of the cardiopulmonary baroreceptors with an increase in the humeral resistance during the test and impairment of the mechanisms of cutaneous microcirculatory vasoregulation in the forearm. 相似文献
34.
35.
M Perry I Drašković T van Achterberg GF Borm MIJ van Eijken PL Lucassen MJFJ Vernooij-Dassen MGM Olde Rikkert 《BMC health services research》2008,8(1):71
Background
Early diagnosis of dementia benefits both patient and caregiver. Nevertheless, dementia in primary care is currently under-diagnosed. Some educational interventions developed to improve dementia diagnosis and management were successful in increasing the number of dementia diagnoses and in changing attitudes and knowledge of health care staff. However, none of these interventions focussed on collaboration between GPs and nurses in dementia care. We developed an EASYcare-based Dementia Training Program (DTP) aimed at stimulating collaboration in dementia primary care. We expect this program to increase the number of cognitive assessments and dementia diagnoses and to improve attitudes and knowledge of GPs and nurses. 相似文献36.
37.
目的:构建重组人粒细胞-巨噬细胞集落刺激因子乳酸链球菌表达载体,为进一步研究人粒细胞-巨噬细胞集落刺激因子在乳链菌的表达及其治疗价值奠定基础。方法:实验于2005-04/2006-03在南方医科大学南方医院消化病研究所完成。①载体pNCSF的构建:将质粒集落刺激因子及含有P59启动子、USP45蛋白信号肽的pNBC1000质粒分别加入BamH Ⅰ和Pst Ⅰ进行双酶切,并用Apa Ⅰ、Sac Ⅰ进行双酶切鉴定,重组质粒命名为pNCSF。②SDGFP的TA克隆及载体pNCSFGFP的构建:将经过优化适合在乳链菌表达的人粒细胞-巨噬细胞集落刺激因子基因克隆于含有P59启动子、USP45蛋白信号肽的pNBC1000载体,得到重组质粒pNCSF;同时设计上下游引物经PCR扩增增强荧光表达蛋白(EGFP),TA克隆后经测序验证,再连接于pNCSF获得重组质粒pNCSFGFP。③载体pTRCSF、pTRCSFGFP的建立:将获得的pNCSF和pNCSFGFP进一步克隆于穿梭载体pTR1001c,以获得人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP。结果:①载体pNCSF构建结果:酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子)720bp的目的片段。②SDGFP的TA克隆及载体pNCSFEGFP的构建结果:SDGFP阳性克隆产物经EcoRⅠ酶切鉴定得到775bp目的片段。pNCSFEGFP酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子、SDGFP)1495bp的目的片段。③穿梭质粒pTRCSF、pTRCSFGFP酶切鉴定结果:经Xba Ⅰ、Sac Ⅰ进行双酶切鉴定,分别得到约717bp、1492bp大小目的片段。结论:获得了人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP,并经酶切鉴定和测序证实。 相似文献
38.
上海市0~6岁小儿佝偻病的现状调查 总被引:14,自引:0,他引:14
目的:了解上海市小儿佝偻病的现状及影响因素。方法:2005年春季以整群和分层随机抽样法抽取上海市部分城区0~6岁小儿821名,采取问卷调查方法了解小儿的生活环境、饮食习惯、户外活动、营养状况、既往疾病史及母亲的妊娠情况等。佝偻病的诊断以1996年国家卫生部颁布的"婴幼儿佝偻病防治方案"为诊断标准。结果:取得完整有效资料769名,其中男童396名,女童373名;集居儿童456名,散居儿童313名。①小儿佝偻病患病率为17.3%(133/769),其中男童患病率为17.4%、女童为17.2%。②佝偻病与喂养方式(母乳喂养的患病率为13.0%、混合喂养的患病率为17.5%、人工喂养的患病率为25.2%)、鱼肝油添加(按时添加维生素D的患病率为13.5%、偶加或未加维生素D的患病率为32.5%)、居住环境(居住在市区的患病率为23.6%、居住在郊区的患病率为10.6%;集居儿童患病率为13.8%、散居儿童患病率为22.4%)、户外活动时间(经常户外活动的患病率为12.9%、偶尔户外活动的患病率为31.8%)、反复呼吸道感染(小儿有反复呼吸道感染的患病率为26.9%、无反复呼吸道感染的患病率为12.9%)、母孕期缺钙(母孕期有缺钙的患病率为33.2%、无缺钙的患病率为12.0%)等因素有关(P<0.01)。结论:上海市小儿佝偻病患病率有上升趋势。影响因素与城市环境污染、母乳喂养减少、年轻父母科学育儿知识缺乏等有关。 相似文献
39.
激光治疗瘢痕的特征 总被引:3,自引:0,他引:3
目的:介绍国内近20年来激光治疗瘢痕的临床研究概况,以期进一步了解激光治疗瘢痕的新进展。资料来源:应用计算机检索Pubmed和中国生物医学文献数据库1983/2006的相关文章,限定文章语言种类为英文和中文,检索词为“cicatrices(瘢痕),laser(激光)”。资料选择:对资料进行初审,选择临床试验研究文献查找全文。纳入标准:①有明确诊断标准。②随机对照实验或对照试验。有无随访,是否采用盲法不限制。③治疗组干预措施为激光或激光联合药物;对照组干预措施为曲安奈德、冷冻联合曲安奈德或不采用药物措施。排除标准:①非对照研究。②治疗组或对照组的干预措施不符合纳入标准。③机制研究。④重复研究。资料提炼:共收集到相关文献120篇,按上述标准纳入31篇,其余文献均被排除。资料综合:31篇文章中11篇为随机对照研究,10篇为对照研究,各研究的研究期为1~6个月。各研究所纳入的病例数量为10~50例。其中6个研究对比了激光与传统药物治疗瘢痕的疗效及安全性,2个研究进行了激光治疗瘢痕基础研究机制比较,10个研究观察了激光结合与单纯药物或单纯激光对瘢痕的疗效,4个研究比较了激光联合西药治疗瘢痕的疗效,2个研究观察了激光治疗瘢痕的副作用。7篇介绍国内或国外瘢痕治疗的研究情况。结论:激光治疗瘢痕的疗效可靠,具有副作用少,方法简单,安全性高,易被患者接受等优势。但由于激光治疗瘢痕还存在着一定的局限性,今后还需要在激光的穿透深度方面研究。 相似文献
40.
Espinosa I José Carnicer M Catasus L Canet B D'angelo E Zannoni GF Prat J 《The American journal of surgical pathology》2010,34(11):1708-1714
Myometrial invasion is an independent prognostic parameter of the endometrioid carcinomas which correlates with the risk of metastasis to pelvic and/or paraaortic lymph nodes. Recognition of myometrial invasion is sometimes difficult. In fact, myoinvasion is overdiagnosed in routine practice in as many as 25% of the cases. Recently, it has been observed that tumor-associated macrophages stimulate angiogenesis and promote cancer dissemination. Tumor macrophages (CD163), microvessel density (CD31), and hypoxia inducible factor 1 α subunit (HIF1A) were investigated in 64 primary endometrioid carcinomas with (50 cases) and without (14 cases) myometrial invasion as well as in the corresponding regional lymph nodes metastases of 20 of the myoinvasive tumors. Endometrioid carcinomas with myometrial invasion showed higher number of CD163-tumor macrophages and greater microvessel density than endometrioid carcinomas without myometrial invasion (P=0.000 and P=0.000, respectively). In carcinomas confined to the corpus uteri (stage I), expression of HIF1A was associated with deep myoinvasion (stage IC) (P=0.006). There was a significant relationship between microvessel density and CD163-macrophages both in the myoinvasive and nonmyoinvasive tumors. On the other hand, high-grade endometrioid carcinomas had more macrophage infiltrates and microvessels than low-grade tumors (P=0.03 and P=0.07). Also, there was a positive correlation between CD163-macrophages and microvessel density in the primary tumors and their corresponding regional lymph node metastases. These findings link increased microvessel proliferation to stromal macrophage infiltrate and suggest that enhanced tumor angiogenesis, triggered by stromal macrophages, regulates the progression of endometrioid carcinomas. The identical stroma microenvironment found in the primary and the corresponding metastatic tumor suggests that tumor stroma response is determined by the intrinsic biology of the tumor. 相似文献