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41.
J Bunikis L Noppa Y Ostberg AG Barbour S Bergstr?m 《Canadian Metallurgical Quarterly》1996,64(12):5111-5116
A chromosomally encoded 66-kDa protein (P66) of Borrelia spp. that cause Lyme disease has previously been shown to be associated with the spirochetal outer membrane. A topological model of P66 predicts a surface-exposed fragment which links the N- and C-terminal intramembranous domains of the protein (J. Bunikis, L. Noppa, and S. Bergstr?m, FEMS Microbiol. Lett. 131:139-145, 1995). In the present study, an immunogenic determinant of P66 was identified by a comparison of the immunoreactivities of different fragments of P66 generated either by proteolytic treatment of intact spirochetes or as recombinant proteins expressed in Escherichia coli. The immune response to P66 during natural infection was found to be directed against the predicted surface domain which comprises amino acids at positions 454 through 491. A sequence comparison revealed considerable polymorphism of the surface domains of P66 proteins of different Lyme disease-causing Borrelia species. Five sequence patterns of this domain were observed in the B. garinii strains studied. In contrast, sequences of the relevant part of P66 of the B. afzelii and B. burgdorferi sensu stricto isolates studied were identical within the respective species. In immunoblotting, 5 of 17 (29.4%) sera from North American patients with early disseminated or persistent Lyme disease reacted against P66 of B. burgdorferi sensu stricto B31. These sera, however, failed to recognize P66 of B. afzelii and B. garinii, as well as an analog of P66 in the relapsing fever agent, B. hermsii. In conclusion, the topological model of P66 is supported by the demonstration of an apparent surface localization of an immunoreactive domain of this protein. Furthermore, analogous to the plasmid-encoded borrelial outer surface proteins, the predicted surface-exposed portion of chromosomally encoded P66 appears to be antigenically heterogenous. 相似文献
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Steven S Fu Miles McFall Andrew J Saxon Jean C Beckham Timothy P Carmody Dewleen G Baker Anne M Joseph 《Nicotine & tobacco research》2007,9(11):1071-1084
We conducted a systematic review of what is known about the relationship between post-traumatic stress disorder (PTSD) and smoking to guide research on underlying mechanisms and to facilitate the development of evidence-based tobacco treatments for this population of smokers. We searched Medline, PsychINFO, and the Cochrane Central Register of Controlled Trials and identified 45 studies for review that presented primary data on PTSD and smoking. Smoking rates were high among clinical samples with PTSD (40%-86%) as well as nonclinical populations with PTSD (34%-61%). Most studies showed a positive relationship between PTSD and smoking and nicotine dependence, with odds ratios ranging between 2.04 and 4.52. Findings also suggest that PTSD, rather than trauma exposure itself, is more influential for increasing risk of smoking. A small but growing literature has examined psychological factors related to smoking initiation and maintenance and the overlapping neurobiology of PTSD and nicotine dependence. Observational studies indicate that smokers with PTSD have lower quit rates than do smokers without PTSD. Yet a few tobacco cessation treatment trials in smokers with PTSD have achieved quit rates comparable with controlled trials of smokers without mental disorders. In conclusion, the evidence points to a causal relationship between PTSD and smoking that may be bidirectional. Specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. Intervention studies that test behavioral and pharmacological interventions designed specifically for use in patients with PTSD are needed to reduce morbidity and mortality in this population. 相似文献
45.
Most (98%) of the fat in human milk is present as triglycerides. This paper describes the use of a clarification procedure that enables the level of human milk fat to be determined by measurement of glycerol released by enzymic hydrolysis of triglycerides. The method requires only 10-50 microliters milk, thus presenting a possible technique for work with small mammals, and is suitable for use with autoanalysers, permitting rapid sample throughput. 相似文献
46.
A novel method for the crosslinking of poly(ethylene terephthalate) fibers is described using 1,6‐hexanedisulfonyl azide, 1,3‐benzenedisulfonyl azide, and 2,6‐naphthalenedisulfonyl azide. The azides are diffused into poly(ethylene terephthalate) fibers (Dacron) from perchloroethylene solution, and the fibers are heat treated to bring about decomposition of the sulfonyl azide and give rise to crosslinking. A study is made of the mechanical and thermal properties of the resultant fibers, which are changed considerably in comparison to the untreated fiber. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1517–1527, 2002 相似文献
47.
KC Halling BW Scheithauer AC Halling AG Nascimento SC Ziesmer PC Roche PC Wollan 《Canadian Metallurgical Quarterly》1996,106(3):282-288
OBJECTIVES--(1) to evaluate regional cerebral blood flow (rCBF) with single photon emission computed tomography and 99mTc-hexamethylpropyleneamine oxime in patients with the idiopathic adult hydrocephalus syndrome (IAHS); (2) to examine regional cerebral blood flow (rCBF), gait, and psychometric functions before and after CSF removal (CSF tap test); (3) to assess abnormalities in subcortical white matter by MRI. METHODS--Thirty one patients fulfilling the criteria for IAHS (according to history and clinical and neuroradiological examination) were studied. Quantified gait measurements, psychometric testing, and rCBF before and after removal of CSF were obtained. Pressure of CSF and CSF outflow conductance were investigated with a constant pressure infusion method. Brain MRI was used to quantify the severity of white matter lesions and periventricular hyperintensities. In IAHS a widespread rCBF hypoperfusion pattern was depicted, with a caudal frontal and temporal grey matter and subcortical white matter reduction of rCBF as the dominant feature. Removal of CSF was not accompanied by a concomitant increase in rCBF. Significant white matter lesions were detected only in a minority of patients by MRI. An altered CSF hydrodynamic state with a higher CSF pressure and lower conductance was confirmed. IAHS is characterised by an abnormal CSF hydrodynamic state, associated with a widespread rCBF reduction with preference for subcortical white matter and frontal-temporal cortical regions. Furthermore in most patients MRI did not show white matter changes suggestive of a coexistent subcortical arteriosclerotic encephalopathy. At least in the idiopathic group of patients with AHS, measurements of rCBF before and after temporary relief of the CSF hydrodynamic disturbance will not provide additional information that would be helpful in the preoperative evaluation but is suggestive of a preserved autoregulation of rCBF. 相似文献
48.
“Study of a Numerically Modeled Severe Storm” is a well known animation within the scientific visualization community. The visualization is among the best of its genre, featuring full storyboarding, well chosen representations, high quality rendering, and professional narration. We recently revisited the thunderstorm to consider what we would do differently if we were to make that video again. We wanted to demonstrate several principles of effective information presentation, drawing from the fields of graphic design and visual perception. Our purpose was not to find fault with bad visualization. Rather, we wanted to study how to make a good thing better. The original video was produced using the modeling, animation, and rendering capabilities of Wavefront's Advanced Visualizer. To facilitate comparison, we did most of the current work with the same software. However, many points discussed here apply to interactive visualization tools as well. The original visualization and our revised version are both based on data generated by a simulation run on a Cray supercomputer at NCSA. The simulation models the genesis and lifetime of a severe storm by solving a set of time dependent equations over a collection of regularly spaced grid points in a three dimensional rectangular space 相似文献
49.
Salicylate-kodein is a widely used analgesic agent, particularly in outpatient practice. Salicylates have been incriminated in hepatic injury while kodein may induce biliary spasm. We report here a case of granulomatous hepatitis attributed to prolonged intake of this combination, which has never been reported previously to our knowledge. 相似文献
50.
B van Hout D Gagnon E Souêtre S Ried C Remy G Baker P Genton H Vespignani P McNulty 《Canadian Metallurgical Quarterly》1997,38(11):1221-1226
PURPOSE: The relationship between seizure frequency and both health care costs and quality of life (QOL) was investigated in a retrospective, cross-sectional, multicenter study in France, Germany, and the United Kingdom. METHODS: Three hundred outpatients with stable partial epilepsy were approximately evenly distributed among five seizure-frequency groups, ranging from seizure-free in the last 3 months (group 1) to daily seizures (group 5). Economic data, obtained through patient interviews and record abstraction, comprised direct medical costs, direct nonmedical costs, and indirect costs for the preceding 3 months. Total societal costs in the three countries were pooled and converted to United States dollar equivalents. QOL was assessed through a self-administered questionnaire, the Functional Status Questionnaire (FSQ). RESULTS: Mean total costs increased from $780 in group 1 to $2,171 in group 5 (p = 0.0001), with significant increases in each cost category as seizure frequency increased. Greater seizure frequency also significantly (p = 0.0270) correlated with lower employment rates, which ranged from 57% in group 1 to 30% in group 5. QOL declined as seizure frequency increased. Particularly affected were basic and intermediate activities of daily living (ADL), mental health, social activity, and feeling about health. CONCLUSIONS: The study results show that higher seizure frequencies are associated with higher direct and indirect costs and with reduced QOL for patients with epilepsy. 相似文献