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11.
Chakrabarti A Singh K Narang A Singhi S Batra R Rao KL Ray P Gopalan S Das S Gupta V Gupta AK Bose SM McNeil MM 《Journal of clinical microbiology》2001,39(5):1702-1706
An outbreak of nosocomial fungemia due to the unusual yeast, Pichia anomala occurred in the pediatric wards of our hospital over a period of 23 months (April 1996 to February 1998). A total of 379 neonates and children (4.2% admissions) were infected. The probable index case was admitted to the pediatric emergency ward, with subsequent transmission to the premature nursery, pediatric intensive care units, and other children wards. Carriage on the hands of health care personnel was likely to be responsible for dissemination of the fungus. The outbreak could only be controlled after a health education campaign to improve hand-washing practices was instituted and after nystatin-fluconazole prophylaxis to all premature neonates and high-risk infants was introduced. In a case-control study, we identified a lower gestational age, a very low birth weight (<1,500 g), and a longer duration of hospital stay as significant risk factors associated with P. anomala fungemia in premature neonates. We conducted a culture prevalence survey of 50 consecutive premature neonates and found that 28% were colonized with P. anomala at a skin or mucosal site on the date of delivery and that 20% of these neonates subsequently developed P. anomala fungemia. We performed multilocus enzyme electrophoresis on 40 P. anomala outbreak isolates (including patient and health care workers' hand isolates), and the results suggested that these isolates were identical. Our study highlights the importance of P. anomala as an emerging nosocomial fungal pathogen. 相似文献
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Characteristics of motile curved rods in vaginal secretions 总被引:7,自引:0,他引:7
M S Sprott H R Ingham R S Pattman R L Eisenstadt G R Short H K Narang P R Sisson J B Selkon 《Journal of medical microbiology》1983,16(2):175-182
Motile curved rods seen in vaginal secretions have been isolated on Columbia agar supplemented with 5% human blood and vitamin K. Growth occurred anaerobically and in 5% oxygen but not in more aerobic conditions. There were two distinct groups of these organisms, distinguishable by morphology, biochemical activity and susceptibility to metronidazole. All isolates were sensitive to a wide range of antimicrobial agents, with the exception of nalidixic acid and polymyxin, but one group was resistant to metronidazole. There was little difference between the results of tests of susceptibility to aminoglycosides or to metronidazole performed in anaerobic and microaerophilic conditions. Motile curved rods were isolated from 18 of 80 patients with a clinical diagnosis of non-specific vaginitis, but from only two of 39 without the disease. 相似文献
14.
Selection by phage display of llama conventional V(H) fragments with heavy chain antibody V(H)H properties 总被引:4,自引:0,他引:4
Tanha J Dubuc G Hirama T Narang SA MacKenzie CR 《Journal of immunological methods》2002,263(1-2):97-109
A llama single domain antibody (dAb) library designed and constructed to contain only heavy chain antibody variable domains (V(H)Hs) also contained a substantial number of typical conventional antibody heavy chain variable sequences (V(H)s). Panning the library against two carbohydrate-specific antibodies yielded anti-idiotypic dAbs and enriched solely for sequences from the V(H) subpopulation of the library. The conventional antibody origin of these V(H)s was confirmed by using oligonucleotide probes, specific for the enriched V(H)s, to identify the parental sequences in the message employed in library construction. Surprisingly, these V(H) dAbs, which are produced in high yield in Escherichia coli, are highly soluble, have excellent temperature stability profiles and do not display any aggregation tendencies. The very close similarity of these molecules to human V(H)s makes them potentially very useful as therapeutic dAbs. 相似文献
15.
Algorithms such as convolution superposition, Batho, and equivalent pathlength which were originally developed and validated for conventional treatments under conditions of electronic equilibrium using relatively large fields greater than 5 x 5 cm2 are routinely employed for inhomogeneity corrections. Modern day treatments using intensity modulated radiation therapy employ small beamlets characterized by the resolution of the multileaf collimator. These beamlets, in general, do not provide electronic equilibrium even in a homogeneous medium, and these effects are exaggerated in media with inhomogenieties. Monte Carlo simulations are becoming a tool of choice in understanding the dosimetry of small photon fields as they encounter low density media. In this study, depth dose data from the Monte Carlo simulations are compared to the results of the convolution superposition, Batho, and equivalent pathlength algorithms. The central axis dose within the low-density inhomogeneity as calculated by Monte Carlo simulation and convolution superposition decreases for small field sizes whereas it increases using the Batho and equivalent pathlength algorithms. The dose perturbation factor (DPF) is defined as the ratio of dose to a point within the inhomogeneity to the same point in a homogeneous phantom. The dose correction factor is defined as the ratio of dose calculated by an algorithm at a point to the Monte Carlo derived dose at the same point, respectively. DPF is noted to be significant for small fields and low density for all algorithms. Comparisons of the algorithms with Monte Carlo simulations is reflected in the DCF, which is close to 1.0 for the convolution-superposition algorithm. The Batho and equivalent pathlength algorithms differ significantly from Monte Carlo simulation for most field sizes and densities. Convolution superposition shows better agreement with Monte Carlo data versus the Batho or equivalent pathlength corrections. As the field size increases the DCF's for all algorithms converge toward 1.0. The largest differences in DCF are at the interface where changes in electron transport are greatest. For a 6 MV photon beam, electronic equilibrium is restored at field sizes above 3 cm diameter and all of the algorithms predict dose in and beyond the inhomogeneous region equally well. For accurate dosimetry of small fields within and near inhomogeneities, however, simple algorithms such as Batho and equivalent pathlength should be avoided. 相似文献
16.
Double light pulse resolution required longer inter-pulse time intervals of short duration of the pulse. The threshold of double pulse discrimination was not contingent upon the actual phase of cardiac or respiratory cycle. 相似文献
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One dimensional manual tracking was investigated in relation to actual heart rate and phase of cardiac cycle. Higher heart rate was combined with increased tracking error incidence and decreased successful tracking time (light spot inside target). Error incidence was time-locked with respect to the phase of cardiac cycle. 相似文献
19.
San Lazaro Campillo Indra Meaney Sarah Sheehan Jacqueline Rice Rachel O’Donoghue Keelin 《Maternal and child health journal》2021,25(2):282-292
Maternal and Child Health Journal - To assess university students’ knowledge of reproductive health information about miscarriage. A single-centre, cross-sectional study was carried out using... 相似文献
20.
Mark Ehlers Marc Bjurlin John Gore Raj Pruthi Gopal Narang Ray Tan Matthew Nielsen Anqi Zhu Allison Deal Angela Smith 《Urologic oncology》2021,39(1):76.e1-76.e7
ObjectiveFinancial toxicity (FT) has been defined as the patient-level impact of the costs of cancer care. Our objective was to better characterize FT among bladder cancer patients as well as oncologic, demographic and insurance characteristics related to FT.MethodsWe conducted a cross-sectional survey of the Bladder Cancer Advocacy Network Patient Survey Network using the validated COST (COmprehensive Score for financial Toxicity) questionnaire. Our primary outcome was relative degree of FT, with lower COST scores corresponding to worse FT. Wilcoxon rank sum tests and multiple regression were used to evaluate differences in demographic, diagnostic and treatment characteristics as they related to degree of FT.ResultsAmong 226 patients, median age was 68 years with 64% male, 83% married, and 49% with Medicare with supplemental insurance. Respondents reported an average of 65 months since diagnosis, with 62% reporting noninvasive disease. Mean COST was 28.4 (range 0–44). On multivariable analysis, patients who were younger, with a household annual income less than $50,000, not retired, or with insurance that was neither Medicare nor employer paid were significantly more likely to have worse FT. A majority of respondents (63.5%) agreed or strongly agreed that they would be interested in discussing cost in the context of their treatment preferences, independent of COST score (P = 0.24).ConclusionsA national cross-sectional survey demonstrated high prevalence of FT which was worse among younger patients with lower incomes, not retired, and without employer-paid or Medicare insurance. Most patients preferred to discuss treatment costs with their bladder cancer provider. 相似文献