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121.
Prevalence and Risk Factors of Helicobacter pylori Infection in Saudi Children: A Three‐Year Prospective Controlled Study 下载免费PDF全文
122.
123.
Nurlisa Yusuf Ammar Zakaria Mohammad Iqbal Omar Ali Yeon Md Shakaff Maz Jamilah Masnan Latifah Munirah Kamarudin Norasmadi Abdul Rahim Nur Zawatil Isqi Zakaria Azian Azamimi Abdullah Amizah Othman Mohd Sadek Yasin 《BMC bioinformatics》2015,16(1)
Background
Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.Results
This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.Conclusions
The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques. 相似文献124.
Avneesh D. Singh Sabaratnam Vikineswary Noorlidah Abdullah Muniandy Sekaran 《World journal of microbiology & biotechnology》2011,27(3):535-545
The potential of ligninolytic enzymes, including lignin peroxidase (LiP) as the main enzyme from the spent mushroom substrate
of Pleurotus sajor-caju was evaluated for the decolourisation of five dyes from azo and anthraquinone dye groups. Among the azo dyes, reactive black
5 and reactive orange 16 were 84.0 and 80.9% decolourised respectively, after 4 h of incubation with 45 U of LiP as compared
to 32.1% decolourisation of disperse blue 79. Among the anthraquinone dyes, disperse red 60 was decolourised to 47.2% after
4 h of incubation with 45 U of LiP as compared to 5.9% decolourisation of disperse blue 56. Increasing the LiP concentration
and incubation time had a positive effect on the decolourisation of anthraquinone dyes as compared to azo dyes. A 67.9% decolourisation
of synthetic textile waste-water was achieved after 4 h of incubation with 25 U of LiP. Increasing the incubation time significantly
increased (P < 0.05) the decolourisation of synthetic textile waste-water. Further, there was a 52.4% reduction in the toxicity of synthetic
textile waste-water treated with 55 U of LiP for 4 h. However, only 35.7% reduction in toxicity was achieved when the synthetic
textile waste-water was treated with 55 U of LiP for 24 h. In this study, it was shown that the spent mushroom substrate of
P. sajor-caju could be a cheap source of ligninolytic enzymes for the decolourisation of dyes in textile industry wastewaters. 相似文献
125.
Biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and characterisation of its blend with oil palm empty fruit bunch fibers 总被引:1,自引:0,他引:1
Poly(3-hydroxybutyrate-co-38 mol%-3-hydroxyvalerate) [P(3HB-co-38mol%-3HV)] was produced by Cupriavidus sp. USMAA2-4 in the presence of oleic acid and 1-pentanol. Due to enormous production of empty fruit bunch (EFB) in the oil palm plantation and high production cost of P(3HB-co-3HV), oil palm EFB fibers were used for biocomposites preparation. In this study, maleic anhydride (MA) and benzoyl peroxide (DBPO) were used to improve the miscibility between P(3HB-co-3HV) and EFB fibers. Introduction of MA into P(3HB-co-3HV) backbone reduced the molecular weight and improved the thermal stability of P(3HB-co-3HV). Thermal stability of P(3HB-co-3HV)/EFB composites was shown to be comparable to that of commercial packaging product. Composites with 35% EFB fibers content have the highest tensile strength compared to 30% and 40%. P(3HB-co-3HV)/EFB blends showed less chemicals leached compared to commercial packaging. 相似文献
126.
The present study investigates the formation of aerobic granular sludge in sequencing batch reactor (SBR) fed with palm oil mill effluent (POME). Stable granules were observed in the reactor with diameters between 2.0 and 4.0 mm at a chemical oxygen demand (COD) loading rate of 2.5 kg COD m−3 d−1. The biomass concentration was 7600 mg L−1 while the sludge volume index (SVI) was 31.3 mL g SS−1 indicating good biomass accumulation in the reactor and good settling properties of granular sludge, respectively. COD and ammonia removals were achieved at a maximum of 91.1% and 97.6%, respectively while color removal averaged at only 38%. This study provides insights on the development and the capabilities of aerobic granular sludge in POME treatment. 相似文献
127.
Morning- and evening-type individuals differ on a number of psychological and biological variables. There has been increasing interest in the relationship between chronotype and personality traits. The aim of this study was to investigate the relationship between impulsivity and chronotype in suicide attempters. Eighty-nine suicide attempters were included in the study, and systematic information on suicide attempts was recorded. The Morningness-Eveningness Questionnaire was applied to determine chronotype, and attempter impulsivity was measured by the total score of the Barratt Impulsiveness Scale. Significant differences between chronotype and impulsivity scores were found. Evening-type subjects reported significantly higher impulsivity scores than both neither- and morning-types. A significant association between chronotype and type of suicide attempt was detected. The largest proportion of violent suicide attempters were evening-type subjects. Violent suicide attempters also reported significantly higher impulsivity scores than nonviolent attempters. Previous studies have pointed out possible relations between eveningness and impulsivity. Current findings suggest that eveningness may be a risk factor for violent suicide attempts by increasing impulsivity. 相似文献
128.
Bicer M Akil M Sivrikaya A Kara E Baltaci AK Mogulkoc R 《Journal of physiology and biochemistry》2011,67(4):511-517
The present study aims to examine the effect of supplementation of zinc on the distribution of various elements in the sera
of diabetic rats subjected to an acute swimming exercise. A total of 80 Sprague–Dawley-type adult male rats were equally allocated
to one of eight groups: Group 1, general; Group 2, zinc-supplemented; Group 3, zinc-supplemented diabetic; Group 4, swimming
control; Group 5, zinc-supplemented swimming; Group 6, zinc-supplemented diabetic swimming; Group 7, diabetic swimming; and
Group 8, diabetes. The rats were injected with 40 mg/kg/day subcutaneous streptozotocin (STZ) twice, with a 24-h interval
between two injections. Zinc was supplemented at a dose of 6 mg/kg/day (ip) for 4 weeks. Blood samples were collected at the
end of the 4-week study, and serum levels of lead, cobalt, molybdenum, chrome, sulfur, magnesium, manganese, sodium, potassium,
phosphorus, copper, iron, calcium, zinc, and selenium (mg/L) were determined with atomic emission. The lowest molybdenum,
chrome, copper, iron, potassium, magnesium, sodium, phosphorus, lead, selenium, and zinc values were obtained in Group 7 and
8. These same parameters were higher in the swimming exercise group (Group 4), relative to all other groups. The values in
zinc-supplemented groups were found lower than the values in Group 4, but higher than those in Group 6 and 7. The results
obtained from the study demonstrate that acute swimming exercise and diabetes affect the distribution of various elements
in the serum, while zinc supplementation can prevent the negative conditions associated with both exercise and diabetes. 相似文献
129.
Gul M Dogan E Kirecci E Ucmak H Dirican E Karadag A 《Acta microbiologica et immunologica Hungarica》2011,58(3):235-238
Serratia ficaria was first described in 1979 as a Gram-negative facultative anaerobic rod. S. ficaria was found in figs, but also isolated from human specimens in a few cases. We now report an isolate of S. ficaria from sputum specimen.A 46-year-old man was suffering from a chronic renal failure of five years, four months of peritoneal dialysis and one week of fever due to respiratory tract infection, accompanied by cough. Sputum culture yielded a Gram-negative rod. It was identified as S. ficaria and the antibiotic susceptibility test was performed by automated Vitek II (bioMerieux). The tested S. ficaria strain was susceptible to amikacin, gentamicin, cefepime, trimethoprim-sulfamethoxazole, imipenem, meropenem, tigecycline and ciprofloxacin. This strain was resistant to ampicillin, amoxicillin-clavulanic acid, cephalothin, cefoxitine, cefuroxime and ceftriaxone. The patient was treated successfully (80 mg trimethoprim/400 mg sulfamethoxazole twice daily for 7 days)S. ficaria is an opportunistic pathogen responsible for intestinal colonization or serious infections such as septicaemia, gall bladder empyema in immunocompromised patients. The fig tree and fig play an important role in human colonization. It should be remembered that S. ficaria infections may be encountered frequently especially in fig tree culture zones. 相似文献
130.
Hind Abdullah Seed Alzahrani 《Saudi Journal of Biological Sciences》2011,18(1):29-36
Recent findings of acrylamide (AA) in many common foods have sparked renewed interest in assessing human health hazards. AA was evaluated by the International Agency for Research on Cancer as probably carcinogenic to humans. For this reason, the aim of this study is to evaluate the potential genotoxic effect of AA using chromosomal aberration analysis and micronucleus (MN) test in mouse bone-marrow cells and morphological sperm abnormalities. The result of the present work indicated that treatment with a single dose of 10, 20, or 30 mg/kg b.wt. of AA for 24 h and the repeated dose of 10 mg/kg b.wt. for 1and 2 weeks induced a statistically significant increase in the percentage of chromosomal aberrations and micronuclei in bone- marrow cells. These percentages reduced significantly in all groups treated with AA and the protective agent l-carnitine. Also the results indicated that the dose 10, 20 and 30 mg/kg b.wt. of AA induced a statistically significant percentage of morphological sperm abnormalities compared with the control group. Such effect reached its maximum (7.24 ± 0.61) with the highest tested dose which reduced to (4.02 ± 0.58) in the group treated with the same dose of AA and l-carnitine. In conclusion, the results confirm the protective role of LC against the mutagenicity of AA. 相似文献