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61.
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
62.
Members of the Alu family of repetitive elements occur frequently in the human genome and are often polymorphic. Techniques involving Alu element mediated polymerase chain reactions (Alu PCR) allow the isolation of region-specific human DNA fragments from mixed DNA sources. Such fragments are a source of region-specific Alu elements useful for the detection of Alu-related polymorphisms. A clone from human chromosome 5, corresponding to locus D5F40S1, was isolated using Alu PCR differential hybridization. Alu elements within this clone were investigated for the presence of potentially polymorphic 3' polyA tails. Primers were devised to amplify the 3' polyA tail of an Alu element present within the clone. One primer, D5F40S1-T, was specific to the DNA flanking the 3' end of the Alu element, and the other primer was homologous to sequences within the element. When these primers were used in PCR reactions, products from chromosomes 2 and 17 (loci D2F40S2 and D17F40S3) were amplified in addition to the expected product from chromosome 5. The most likely explanation for this nonspecific amplification is that the D5F40S1-T primer is located within a low-copy repetitive element that is 3' of the Alu element. This phenomenon presents a potential problem for the identification of region-specific Alu polymorphisms. 相似文献
63.
64.
A New Approach to Abstract Syntax with Variable Binding 总被引:1,自引:1,他引:0
The permutation model of set theory with atoms (FM-sets), devised by Fraenkel and Mostowski in the 1930s, supports notions
of ‘name-abstraction’ and ‘fresh name’ that provide a new way to represent, compute with, and reason about the syntax of formal
systems involving variable-binding operations. Inductively defined FM-sets involving the name-abstraction set former (together
with Cartesian product and disjoint union) can correctly encode syntax modulo renaming of bound variables. In this way, the
standard theory of algebraic data types can be extended to encompass signatures involving binding operators. In particular,
there is an associated notion of structural recursion for defining syntax-manipulating functions (such as capture avoiding
substitution, set of free variables, etc.) and a notion of proof by structural induction, both of which remain pleasingly
close to informal practice in computer science.
Received October 2000 / Accepted in revised form April 2001 相似文献
65.
Hamed Rezaishiraz Andrew Hyland Martin C Mahoney Richard J O'Connor K Michael Cummings 《Nicotine & tobacco research》2007,9(11):1139-1146
The present study investigated whether treatment with the combination of denicotinized cigarettes and 21-mg nicotine patch for 2 weeks before a designated quit date could lessen cravings for smoking, thereby helping smokers abstain from smoking. The study was a randomized controlled clinical trial conducted at Roswell Park Cancer Institute, Buffalo, New York, in 2004 and 2005. Patients included 98 adult heavy smokers (using 20 or more cigarettes/day). Half of the subjects received 2 weeks of combination of denicotinized cigarettes (Quest 3) and 21-mg nicotine patch for 2 weeks before the quit date. The remaining smokers were switched to light cigarettes (Quest 1) during the 2 weeks before the quit date. After the quit date, all subjects received counseling for smoking cessation and were provided nicotine patches for up to 8 weeks after the quit date. Self-reported cravings for smoking, withdrawal symptoms, and smoking abstinence were measured at predetermined intervals using phone-based surveys and in clinical visits. The group that used denicotinized cigarettes and nicotine patch before quitting reported less frequent and less intense cravings for cigarettes in the 2 weeks before and after the designated quit date. Self-reported withdrawal symptoms and quit rates did not differ significantly between the groups. The use of a denicotinized cigarette combined with the nicotine patch appears to lessen cravings to smoke in the immediate postcessation period. A larger, better-powered study is needed to test if this treatment combination has merit for increasing quit rates. 相似文献
66.
BACKGROUND AND PURPOSE: Norway has the highest reported incidence of hip fractures in western Europe. Little is known about the epidemiology of falls in Norway where the winter season is long and dark. The objective of this work was to study reported falls and their consequences among elderly Norwegians living at home. METHODS: A cross-sectional design was used for the study. Interviews were performed in the homes of 431 subjects, aged 67-97 years, living at home. Information on falling was gathered through six questions: whether the subject had fallen during the last six months, and if so, how many falls they had, where the last fall occurred, its perceived reason, the activity the subject had been engaged in when the fall occurred, and the resulting injury. RESULTS: In all, 24.1% of subjects reported falling during the last six months, and 9.5% had suffered more than one fall. Falls were most frequently linked to external events (63.1%). Outdoor falls were more frequent (59.0%; 95% CI = 51.2-82.0) than indoor falls. Older subjects were associated with more frequent indoor falls (p < 0.05), but gender was not significant. Fifty-one per cent of subjects had fallen while walking and 53% had suffered an injury from the last fall. In 13.4% of the women and 16.2% of the men, the last fall had resulted in a fracture. CONCLUSIONS: Compared to the results of other studies from industrialized Western countries, a similar crude fall rate, similar frequency and similar type of injury were found. However, in contrast to other studies, no gender difference was observed with regard to falling, place of falling and fracture rate. 相似文献
67.
G Zoli GR Corazza S Wood R Bartoli G Gasbarrini MJ Farthing 《Canadian Metallurgical Quarterly》1998,43(6):759-762
Relatively little is known about the occurrence of neurocysticercosis in northeastern Brazil. There have been no published reports from the state of Ceará, but a review of the records at the Hospital S?o José in Fortaleza, Brazil identified 119 patients with neurocysticercosis diagnosed between January 1988 and April 1994. Patients came from 43 municipalities in Ceará. Their ages ranged from five to 74 years; the greatest number of cases were in persons 10-40 years of age; 63% were males. Seizures were the presenting complaint in 64% of the patients and headache in 22%. Two patients, each with several hundred intracranial lesions, presented with mental status changes; one was initially given the clinical diagnosis of viral meningoencephalitis. Computed tomography scans showed that 44% of the patients had five or more lesions. Cysts were found throughout the brain. The parietal lobe was the most frequent site of involvement; 85% of patients had one or more lesions there. The brain stem was involved in 8%. There was no consistent association between the severity of the clinical abnormalities and the radiologic findings. Computed tomography of the thighs was done in 10 persons; cysts were identified in nine. 相似文献
68.
Six experiments are reported that contrasted the effects of frequency and age of acquisition on written word recognition. Age of acquisition affected word-naming speed when frequency was controlled (Experiment 1), but there was no effect of frequency when age of acquisition was controlled (Experiment 2). Experiments 3 and 4 found an effect of age of acquisition upon immediate but not delayed naming speed, but no frequency effect on either immediate or delayed naming once age of acquisition was controlled. Independent effects of frequency and age of acquisition were observed in the lexical decision task (Experiments 5 and 6). Implications for theoretical accounts of word recognition and the possible roles of age of acquisition and frequency in word recognition are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Clotilde LM Bernard C Sequera DE Karmali A Fusellier A Carter JM 《Journal of laboratory automation》2012,17(4):309-314
Conventional enzyme-linked immunosorbent assay (ELISA) is a gold standard for screening antibodies and testing for protein or antigen presence. A significant limitation of this assay resides in the fact that only one analyte can be assessed per microplate well. Here, we describe and investigate a new technology consisting of an automated ELISA system in which up to 10 analytes can be measured within one single well, thus improving productivity, accuracy, and repeatability by reducing the amount of human labor required. Another strength of the platform is that a user can load any necessary sets/subsets of beads to perform required assays, with improved flexibility compared to manufactured-loaded arrays for multiplex analysis. We also demonstrate that this system can be used to determine the pathogenicity (i.e., presence of Shiga toxins) and serotype (i.e., Escherichia coli O157) of E. coli isolates. 相似文献
70.
Ceilidh Mackie Jana Levison Andrew Binns Ivan O'Halloran 《Journal of Great Lakes research》2021,47(1):145-159
Nutrient export from agricultural land to surface waters is a significant environmental concern within the Great Lakes Basin (GLB). A field-based watershed-scale study was completed to investigate spatial and temporal variations of phosphorus and nitrate to assess nutrient transport pathways and groundwater-surface water interactions in an agriculturally dominated clay plain system. This was conducted in the 127 km2 Upper Parkhill Watershed, near Lake Huron in southwestern Ontario, Canada. Data collection occurred from June 2018 to May 2019 via continuous sensor deployment and discrete sampling of stream water, groundwater, hyporheic zone, and tile drainage water. Samples were analyzed for various nutrient species (total, total dissolved, soluble reactive, and particulate phosphorus, and nitrate-N) to examine the hydrological dynamics of principal transport pathways of agriculturally-derived nutrients. Total phosphorus and nitrate concentrations in stream water ranged from 0.007 to 0.324 mg/L and 0.32 to 13.13 mg NO3?-N/L, respectively. Tile drainage water total phosphorous concentrations varied from 0.006 to 0.066 mg/L. Groundwater total dissolved phosphorus concentrations ranged from <0.003 to 0.085 mg/L. Transport of phosphorus through tile drainage was observed to be greater than through groundwater over the study period. No distinct relationship was observed between nutrient concentrations in the hyporheic zone and the vertical hydraulic gradient within this zone in the studied stream reach. Preliminary correlations were discerned between water quality observations and recognized land management practices. Given the elevated stream nutrient concentrations, these results are consequential for the continual improvement of strategies and programs devised to conserve water resources within the GLB. 相似文献