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21.
The biodegradation of undecylbenzenesulphonate (C11LAS) was studied in shake flasks at 21°C using two mixed bacterial cultures. The first culture, MM1, contained a type II methanotroph and four heterotrophs, and was enriched from a groundwater aquifer. The second culture, MC, consisted of five heterotrophic strains, most of them belonging to the genus Pseudomonas , and was isolated from the wastewater of a detergent plant. Methane, carbon dioxide and oxygen concentrations were determined by gas chromatography. Concentrations of C11LAS and the aromatic intermediates were determined by reversed-phase HPLC. In spite of faster transformation of the alkyl side-chain by the culture MC, the culture MM1 containing type II methanotroph was capable of further degradation of C11LAS aromatic intermediates (sulphophenylalkanoates). The most probable mechanism for the degradation of the alkyl part of the C11LAS molecule by both cultures was β-oxidation of the terminal methyl group followed by β-oxidation. Studies of methane utilization demonstrated an approximately three times higher second-order rate coefficient for methane consumption ( k max/ K s) in the absence of C11LAS. This indicates a possible metabolic activity of methanotrophs in the transformation of the complex LAS molecule due to the methane monooxygenase enzyme system.  相似文献   
22.
The aim of the present study was to determine the bioactive compounds in four essential oils (EO’s) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO’s and EOC’s (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO’s and EOC’s in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO’s and EOC’s (the essential oil components, carvacrol and thymol) on eradication of preformed 48?h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time.  相似文献   
23.
The study was undertaken to determine the prevalence of chlamydial genital infection in sexually active, urban adolescent females 15-19 years; to identify behavioral, demographic, and clinical factors associated with chlamydial infections; and to develop criteria for potential screening strategies. 500 adolescent women, median age 17.7 years, who visited gynecological outpatient clinic in Children's Hospital Zagreb for different reasons were enrolled in this study. Gynecological exam, colposcopy, detection of chlamydial infection by the rapid direct immunoassay of endocervical swab (Clearview Chlamydia-Unipath), endocervical cytological examination--Papanicolaou smear, and questionnaire to obtain demographic, social, behavioral and presence of symptoms data were performed. Positive Chlamydia trachomatis test were found in 16.4% of participants, cytologic cervical abnormalities--cervical intraepithelial neoplasia (CIN I-CIN III) were found in 25.2% and cytological signs of Human papilloma virus were found in 11.4%. Stepwise multivariate logistic regression analysis identified five factors associated with infection: the age of menarche < or =13 years, > or =4 lifetime sexual partners, non-use of contraception (rare or never), cervical friability, and abnormal Papanicolaou test. Urban adolescent sexually active women are at high risk for chlamydial infection and other sexually transmitted diseases including HIV infection. Association between chlamydial genital infection and risk-taking sexual and contraceptive behavior was found. Routine Chlamydia trachomatis testing for this population is recommended as well as implementation of school based sexual health education because of their risk-taking sexual behavior.  相似文献   
24.
New molybdenum complexes were prepared by the reaction of [MoVIO2(acac)2] or (NH4)2[MoVOCl5] with different N-substituted pyridoxal thiosemicarbazone ligands (H2L1 = pyridoxal 4-phenylthiosemicarbazone; H2L2 = pyridoxal 4-methylthiosemicarbazone, H2L3 = pyridoxal thiosemicarbazone). The investigation of monomeric [MoO2L1(CH3OH)] or polymeric [MoO2L1-3] molybdenum(VI) complexes revealed that molybdenum is coordinated with a tridentate doubly-deprotonated ligand. In the oxomolybdenum(V) complexes [MoOCl2(HL1-3)] the pyridoxal thiosemicarbazonato ligands are tridentate mono-deprotonated. Crystal and molecular structures of molybdenum(VI) [MoO2L1(CH3OH)]·CH3OH, and molybdenum(V) complexes [MoOCl2(HL1)]·C2H5OH, as well as of the pyridoxal thiosemicarbazone ligand methanol solvate H2L3·MeOH, were determined by the single crystal X-ray diffraction method.  相似文献   
25.
We present a case of 23-year-old student misdiagnosed for two months. Radiological finding showed a pneumonial infiltrate of left lung lower lobe. Antibiotical therapy was not resulting in a radiological regression. Biopsy of the lung infiltrate by transthoracic computed tomography guided histology needle, showed granulomatous inflammation with necrosis. Bronchial aspirate received by bronchoscopy was positive in culture on Mycobacterium tuberculosis. After 6 months of antituberculotic therapy advance the complete regression of lung infiltrate. Tuberculosis of lower lung lobe is difficult to diagnose, particularly in persons who are not immunocompromised or without associated diseases. Lower lobe localization of tuberculosis is between 0.6 to 10.5% in all cases. Early diagnosis and therapy of pulmonary tuberculosis depends on bronchoscopic samples. The biopsy of the lung infiltrate by transthoracic computed tomography guided histology needle in histopathological and bacteriological diagnosis of tuberculosis was also useful.  相似文献   
26.
The aim of the study was to assess neonatal birth weight (BW) differences between inland and littoral Croatia, to identify BW groups with most pronounced differences, and possible variations in the rate of BW > or = 4000 g between Sibenik area and the rest of littoral (counties with access to the Adriatic Sea) and inland Croatia. The study included data on 99.42% of 200,740 live births recorded in 37 Croatian maternity hospitals during the 2001-2005 period. Distribution of 500-g BW groups was analyzed irrespective of neonatal sex and gestational age. Differences were found between the inland and littoral parts of Croatia according to distribution of the BW groups of < 2500 g (5.4% vs. 4.4%), 2500-3999 g (84% vs. 80.2%) and > or = 4000 g (10.6% vs. 15.4%) (chi2 = 882; p < 0.001).The highest rate of BW > or = 4000 g was recorded in Sibenik-Knin County (5-year mean 18.32%) and was greater throughout the littoral as compared with inland Croatia (5-year mean 14.99% vs. 9.58%). A shift towards higher BWgroups recorded throughout littoral as compared with inland Croatia supports the hypothesis on variation in anthropologic characteristics in the respective populations to be pronounced as early as at birth. Study results confirmed fetal macrosomia not to be exclusively characteristic of Sibenik-Knin County, since the rate of neonatal BW > or =4000 g was significantly higher in the entire littoral as compared with inland Croatia.  相似文献   
27.
Alveolar bone loss (RRR) is a continuous process following tooth extraction, more pronounced during the first few months after the tooth extraction than later. The RRR in the mandible is twice that of the maxilla during a 1-year period and the mandibular: maxillary resorption ratio increases further to 4:1. So far, the etiology of RRR has not been elucidated. It has been speculated that both systemic and local factors contribute. The aim of this study was to analyse the rate of RRR in five different regions of both jaws on lateral cephalograms of 100 complete denture wearers during a one-year period and to compare the rate of RRR between patients being edentulous over a different period of time and between patients with different body mass index. The height of residual ridges was measured on 5 different sites at the delivery of the dentures and a year later using a calibrated grid. The results revealed significant RRR in a one year period. Body mass index had no significant influence on the rate of RRR on any of the five examined sites of the maxilla or the mandible (p > 0.05), while the period of edentulousness had a significantly higher rate of resorption in first 3 sites of measurement (anteriorly) in patients being edentulous less than 1 year than in patients being edentulous for 1-10 years or for over 10 years (ANOVA, p < 0.05).  相似文献   
28.
The problems related to cancer and its control initially manifest in local community, and general practitioners are those who most commonly have to face them there. The aim of the study was to develop a program of comprehensive oncologic care for primary care physicians, which would be highly professional, efficient, economically justified and feasible, with the ultimate goal of upgrading the target population health and quality of life. Opinions on the priorities and intensity of work in particular activities of general practitioners in the field of oncologic care were obtained from 54 Croatian experts in oncologic care. An Expert Opinion was designed to collect oncologists' opinions by use of Delphi method. The study was performed in two runs, yielding a high rate of accordance among the oncologists. 38 of 54 participants responded in the first run, and 40 of 54 (74%) responded in the second run. The results indicated pain therapy and terminal care to be given highest priority, whereas measures of primary prevention ranked first as a group. There was a unanimous agreement that current activities of primary care physicians in the field of oncologic care were not satisfactory, and that they should take the role of a coordinator of the oncologic care of both individual patients and the population at large. The study showed that a model of oncologic care applicable throughout the country could be developed by combining data from a small health care office with the knowledge of renowned experts in the field.  相似文献   
29.
The presence of porcine endogenous retroviruses presents a potential risk of transmission of infectious diseases (xenozoonosis) if tissues and organs from genetically modified pigs are to be used in xenotransplantation. Here, we report that intracellular expression of a llama single-domain antibody against p15, the matrix domain protein of the porcine endogenous retrovirus Gag polyprotein, blocks retrovirus production, providing the possibility of eliminating the risk of infection in xenotransplantation.  相似文献   
30.
A micromorphological analysis of leaf epidermal tissue of 18 Trifolium species was carried out using light and scanning electron microscopy, in order to obtain qualitative and quantitative data on epidermal characteristics and to evaluate their taxonomic significance. The shape of epidermal cells and their cell walls, epidermal wax depositions, presence of papillae, type and number of stomata, type, distribution and number of non-glandular and glandular trichomes were analyzed. The results showed that species that belong to the same section had some common leaf epidermal characteristics. Combinations of those characters proved to be useful in taxonomy at the level of the sections, but not for identification of single species.  相似文献   
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