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71.
Rosemary Pimm Corneel Vandelanotte Ryan E. Rhodes Camille Short Mitch J. Duncan 《Behavioral medicine (Washington, D.C.)》2013,39(4):248-253
Physical activity is partly regulated by automatic processes such as habits (ie, well-learned responses to cues), but it remains unclear what cues trigger these processes. This study examined the relations of physical activity automaticity and behavior with the consistency of people, activity, routine, location, time, and mood cues present upon initiation of physical activity behavior. Australian adults (N = 1,244, 627 female, M age = 55 years) reported their physical activity automaticity, behavior, and the degree of consistency of these cues each time they start a physical activity behavior. Multiple regression models, which accounted for gender and age, revealed that more consistent routine and mood cues were linked to more physical activity automaticity; whereas more consistent time and people cues were linked to more physical activity behavior. Interventions may more effectively translate into long-lasting physical activity habits if they draw people's attention to the salient cues of time, people, routine, and mood. 相似文献
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74.
Jennifer A. Fike Cecilia A. Hennessy Michael L. Kennedy Olin E. Rhodes Jr 《Conservation Genetics Resources》2013,5(3):679-681
The eastern gray squirrel (Sciurus carolinensis) often serves as a model organism for investigations of wildlife ecology. The authors developed 11 polymorphic microsatellite markers to facilitate future research questions. The number of alleles per locus ranged from three to ten and observed heterozygosities ranged from 0.143 to 0.786. Interspecific screening revealed that several loci were polymorphic in Sciurus niger (eight loci) and Tamiasciurus hudsonicus (four loci). These markers will aid in investigations of movements, social structure and mating tactics of eastern gray squirrel populations. 相似文献
75.
D.P. Miller J.V. McDowell D.V. Rhodes A. Allard M. Caimano J.K. Bell R.T. Marconi 《Molecular oral microbiology》2013,28(4):316-330
Treponema denticola is an anaerobic spirochete whose abundance in the subgingival crevice correlates with the development and severity of periodontal disease. The ability of T. denticola to survive and thrive in the hostile environment of the periodontal pocket is due, at least in part, to its ability to bind factor H (FH), a negative regulator of the alternative complement pathway. The FH binding protein of T. denticola has been identified as FhbB and its atomic structure has been determined. The interaction of FH with T. denticola is unique in that FH bound to the cell surface is cleaved by the T. denticola protease, dentilisin. It has been postulated that FH cleavage by T. denticola leads to immune dysregulation in periodontal pockets. In this study, we conduct a comparative assessment of the sequence, properties, structure and ligand binding kinetics of the FhbB proteins of strains 33521 and 35405. The biological outcome of the interaction of these strains with FH could differ significantly as 33521 lacks dentilisin activity. The data presented here offer insight into our understanding of the interactions of T. denticola with the host and its potential to influence disease progression. 相似文献
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77.
R. Stafford M.D. Farrar R. Kift M.T. Durkin J.L. Berry A.R. Webb L.E. Rhodes 《The British journal of dermatology》2010,163(4):817-822
Background Photosensitivity disorders involve an abnormal skin reaction to sunlight exposure and affect a substantial percentage of the population. No previous studies have directly compared lifestyle attributes between photosensitive and healthy individuals. Objectives To assess the impact of photosensitivity on time spent outdoors in the U.K., holiday behaviour, use of sunscreens and vitamin D supplements, and employment status. Methods Questionnaires were completed by ambulant photosensitive and healthy adults aged 18–60 years residing in Greater Manchester. Results Forty‐five adults with moderate–severe photosensitivity and 124 healthy adults completed the questionnaire. This revealed that photosensitive subjects spent significantly less time outdoors in the U.K. on both summer weekdays (P < 0·01) and summer weekends (P < 0·0001) than healthy subjects, took fewer holidays per year (P < 0·05), and spent less time outdoors on a sunny holiday (P < 0·0001). They wore clothing that covered a wider skin area (P < 0·0001), and use of sunscreen was greater (both frequency of application and area covered) in the photosensitive group outside of holiday time (P < 0·0001), but not when on a sunny holiday, as healthy people increased their sunscreen use at this time. Despite the reduced sun exposure, photosensitive subjects were no more likely to take vitamin D supplements than healthy subjects were; they also exhibited a significantly higher rate of unemployment (P < 0·05). Conclusions Photosensitivity disorders negatively influence lifestyle including employment status; more attention is required to the socioeconomic impact of these conditions. 相似文献
78.
Hunnangkul S Nitsch D Rhodes B Chadha S Roberton CA Pessôa-Lopes P Norsworthy PJ Fernando MM Charles P Mackworth-Young C Isenberg DA Whittaker JC Vyse TJ 《Arthritis and rheumatism》2008,58(4):1116-1124
OBJECTIVE: To determine whether key features of systemic lupus erythematosus (SLE), namely, production of non-nuclear antibodies (anti-C1q and anticardiolipin antibodies [aCL]) and depletion of complement components C3 and C4, aggregate in families. In addition, we examined relationships between anti-C1q and C3 and C4 levels. METHODS: The study cohort comprised 1,037 predominantly white (82%) nuclear families in which at least 1 member had SLE. Associations of antibody measurements between probands and their unaffected siblings were examined using parametric and nonparametric analyses, along with associations between unaffected siblings and their parents. The heritability of anti-C1q, C3, and C4 was estimated, and interdependencies between these factors were examined in a regression model accounting for the family structure of the data set. RESULTS: We demonstrated associations between siblings for anti-C1q (odds ratio [OR] 3.74, 95% confidence interval [95% CI] 2.65, 5.28) and IgG and IgM aCL (OR 4.08, 95% CI 1.83, 5.13 and OR 2.06, 95% CI 1.46, 2.91, respectively) and, for anti-C1q, association between unaffected parents and their unaffected offspring (OR 4.34, 95% CI 2.16, 8.72). We also demonstrated significant heritability of anti-C1q, C3, and C4 (approximately 45%). Anti-C1q was negatively associated with C3 and C4 in SLE probands but not in their healthy relatives. CONCLUSION: Non-nuclear antibodies and C3 and C4 cluster within the families of SLE probands, suggesting that specific autoantibody formation is partly genetically determined, even if the total genetic effect in unaffected relatives is insufficient to cause disease. Anti-C1q antibodies accelerate C3 and C4 depletion in patients with SLE but have no effect in the absence of disease. 相似文献
79.
E D Srivastava J R Barton S O'Mahony D I Phillips G T Williams N Matthews A Ferguson J Rhodes 《Gut》1991,32(9):1016-1019
Since ulcerative colitis predominantly affects non-smokers and ex-smokers we have examined the possibility that smoking modifies the humoral immune response to an antigenic challenge from the gut lumen. Gut lavage was used in healthy subjects and patients with ulcerative colitis, including both smokers and non-smokers. Antibodies in the intestinal fluid to Escherichia coli (five pooled serotypes), Candida albicans, gliadin, ovalbumin, and beta lactoglobulin were measured by ELISA to determine specific antibody concentrations of IgG, IgA, and IgM classes. Total IgG, IgA, and IgM were also measured in intestinal secretions and serum. In addition, circulating antibody concentrations of IgG, IgA, and IgM to three gut commensals - E coli (five pooled serotypes) C albicans, and Poroteus mirabilis were measured. There was a significant reduction in the IgA concentration in intestinal fluid of smokers with ulcerative colitis compared with healthy non-smoking controls. No other significant differences were found between the groups. Overall, these data are not consistent with the idea that smoking suppresses immune responses in the gut and suggest that the effect of smoking in colitis is mediated by another mechanism. 相似文献
80.
John R Ingram Gareth A O Thomas John Rhodes John T Green Neil D Hawkes Jill L Swift Emmanuel D Srivastava Brian K Evans Geraint T Williams Robert G Newcombe Edward Courtney Suresh Pillai 《Clinical gastroenterology and hepatology》2005,3(11):1107-1114
BACKGROUND & AIMS: Ulcerative colitis (UC) is largely a disease of nonsmokers in which transdermal nicotine improves the symptoms but often causes adverse events (AEs). Nicotine enemas cause fewer AEs and were used as supplemental treatment for active UC. METHODS: We treated 104 patients with active UC with either 6-mg nicotine enemas or placebo enemas for 6 weeks in a randomized double-blind study. Patients continued their oral therapy, if any, for UC: 68 patients were taking mesalamine, 15 patients were taking prednisolone, and 12 patients were taking thiopurines during the study. Clinical, sigmoidoscopic, and histologic assessments were made at baseline and at the end of the study and symptoms were recorded daily on a diary card. The primary end point was induction of clinical remission and clinical improvement also was measured by the UC disease activity index. After the study, patients then used nicotine enemas daily for 4 weeks and sigmoidoscopy with a biopsy examination was repeated. AEs and salivary cotinine levels were monitored throughout the study. RESULTS: Clinical remission was achieved in 14 of 52 (27%) patients on active treatment and 14 of 43 (33%) patients on placebo (P = .55). The UC disease activity index improved by 1.45 points in the active group and by 1.65 points for those on placebo (P = .88). Only 1 patient discontinued treatment because of an AE (abdominal pain). In the 47 patients taking mesalamine only, active treatment conferred benefit that was not statistically significant; disease remission occurred in 9 of 25 patients on active therapy and 4 of 21 patients on placebo (P = .20). CONCLUSIONS: Six-milligram nicotine enemas were well tolerated but were not found to be efficacious for active UC. 相似文献