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991.
The aim of the present study was to evaluate possible associations between subgingival plaque bacterial morphotypes, as assessed by darkground microscopy, and clinical indices of routine adult chronic periodontitis. Clinical indices were plaque index (PlI), gingival index (GI), sulcus bleeding index (SBI), papilla bleeding index (PBI), attachment loss (AL), pocket depth (PD) and probeable pocket depth (PPD). Apical border plaque was sampled in vivo and after extraction to test whether direct or indirect sampling affected any such associations. Similarly, pocket depth and attachment loss were also assessed directly and indirectly on the same teeth, in vivo or after extraction. The influence of the type of index used to record inflammation (GI, SBI, PBI) was also assessed, as were the effects of the numbers of sampled subjects and the method of analysis, which comprised the use of transformed and untransformed data and of parametric and non-parametric tests. Data were collected in relation to the approximal surfaces of 44 teeth extracted from 22 adults (2 teeth each) and from 1 pair of contralateral upper anterior or premolar teeth in each of 100 adults, all which untreated routine chronic periodontitis. Selected subjects had greater than or equal to 4 mm probeable pocket depth and/or attachment loss, and radiographic evidence of bone loss in relation to 1 approximal surface on each of 1 pair of contralateral anterior or premolar teeth, or to 2 teeth scheduled for extraction. Plaque preparation and darkground microscopy were as described previously. Insignificant associations (p greater than 0.05) were demonstrated between supragingival plaque (PlI) and periodontal inflammation (GI, SBI, PBI) or destruction (PPD and AL), as well as between inflammation and attachment level. In contrast, significant moderate associations (r = 0.5-0.77) were demonstrated between each of the 3 morphotype groups; spirochaetes, other motiles and cocci. Spirochaetes showed a significant moderate (r = 0.5) positive association with pocket depth with a 2.43% mean increase of spirochaetes for each 1 mm increase of PPD. Although highly significant associations (r = 0.9) were demonstrable between the 3 inflammation indices (GI, SBI, PBI) themselves, only PBI showed significant positive associations (r = 0.3) with spirochaetes and other motiles. Also, PlI showed significant associations with each of the 4 morphotypes (r = 0.3-0.5). The heterogeneity of spirochaetes and other motiles as well as the multiplicity of possible aetiological microbial agents in plaque may have resulted in underestimated associations between subjects as well as undetectable association within a given mouth using only 4 morphotype groups.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
992.
993.
D Newman P Dorian E Downar L Harris D Cameron M Waxman R Hamilton R Gow J Hardy 《The American journal of cardiology》1992,70(6):616-621
Twenty patients (aged 50 +/- 21 years and mean left ventricular ejection fraction 37 +/- 17%) with recurrent ventricular arrhythmias were treated with an investigational, implantable combined antitachycardia-pacing cardioverter defibrillator. The device's telemetry capabilities include both stored (1-second snapshots) and real-time display of endocardial and device-circuit signals. The device can store these before, during and after up to 50 tachycardia and antitachycardia pacing episodes. All stored events are indexed to a 24-hour internal clock. During 10.1 +/- 5.1 months of follow-up, the device was used in 11 of 20 patients. In the entire group, antitachycardia pacing was activated on 44 +/- 14 occasions per patient (total 874) and shock delivery occurred on 8 +/- 14 occasions per patient (total 156). Reconstruction by stored telemetry of all device-therapy episodes was possible. Twenty-six percent of all shocks delivered were not appropriate and were due to atrial arrhythmias in 2 patients and dysfunction of the sensing lead in 3. The absence of a relation between symptoms and appropriate shock delivery was documented in 1 patient. Antitachycardia pace acceleration occurred in 5.3% of cases; 7% of attempts at pacing were unsuccessful and needed shock therapy. It is concluded that the enhanced telemetry available in newer antitachycardia devices enables more accurate assessment of device use and enhances diagnosis of inappropriate therapy delivery. 相似文献
994.
995.
Microcapsules made from alginate-poly(L-lysine)-alginate membranes have been studied as vehicles for cell culture in a number of laboratories. We have examined their permeability, robustness and ultrastructure in detail. Permeability to globular proteins could be controlled by using poly-lysine of different mean MW in their construction. However, this parameter also affected the degree to which microencapsulated living cells leaked out of the capsules during and after preparation. Poly-lysine of low MW produced a relatively permeable and robust membrane whereas a high MW produced capsules with the reverse characteristics. A MW of 22,000 appears to be optimal in forming robust capsules which are relatively impermeable to high MW species such as immunoglobulins. The structure of the semipermeable membrane was investigated by electron microscopy and found to be complex but entirely consistent with the data on protein permeability and cell leakage. Microcapsules were not disrupted by gentle treatment with trypsin or chelating agents but dissolved with the addition of heparin, sodium dodecyl sulphate or sodium hydroxide. Empty microcapsules implanted into the peritoneal cavity of rats elicited a host cellular reaction but remained intact for at least three months. 相似文献
996.
Eicosanoids, including epoxyeicosatrienoic acids, hydroxyeicosatetraenoic acids, and other oxylipins derived from polyunsaturated
fatty acids, have emerging roles in endothelial inflammation and subsequent atherosclerosis. Unlike eicosanoids in the prostanoid
series, they are known to be esterified in cell lipids such as phospholipids and triglycerides; however, our understanding
of these reservoirs is in its infancy. This review focuses on recent work identifying circulating oxylipins, primarily esterified
with lipoprotein lipids, and their effects on markers of endothelial dysfunction. These oxylipins are known to be released
by at least one lipase (lipoprotein lipase) and to mediate increased expression of inflammatory markers in endothelial cells,
which coincides with the known roles of lipoproteins in endothelial dysfunction. The implications of the lipolytic release
of lipoproteinbound oxylipins for the inflammatory response, challenges to analysis of this oxylipin compartment, and the
potential importance of non-arachidonatederived oxylipins are discussed. 相似文献
997.
Fluoxetine was given to five nonveteran patients with post-traumatic stress disorder (PTSD). The maximum doses ranged from 20 to 80 mg/day, and treatment was continued for between 8 and 32 weeks. In contrast to published reports of other drugs, which were noted to improve only the intrusive symptoms of PTSD, fluoxetine was associated with marked improvement of both intrusive and avoidant symptoms. Facilitative effects of fluoxetine were noted on trauma-focused psychotherapy in two adult victims of childhood sexual trauma. In part, these effects were related to modulating effects of the drug upon the intensity of core PTSD symptoms. Serotonergic drugs appear to hold promise for the treatment of PTSD.This work was conducted in the Departments of Psychiatry and Psychology, Duke University, Durham, N.C. 相似文献
998.
999.
1000.
The purpose of this study was to determine the nature of the relationships among stress, coping, social support, and weight class in premenopausal African American women as risk factors for coronary heart disease. Overweight and obesity are significant problems for African American women who are at an increased risk of weight-related diseases, such as diabetes, hypertension, cardiovascular disease, and cancer. Of these women, those who are premenopausal have a significantly higher coronary heart disease mortality rate than their white counterparts. There are gaps in current knowledge concerning the role that stress and other psychosocial factors play in weight control of premenopausal African American women. Data were obtained from 178 women with eligible data sets from a larger study of 236 subjects (Genetic Predictors of Coronary Heart Disease in Premenopausal African American Women). The measures for stress, coping, and social support included the Perceived Stress Scale, the Norbeck Social Support Questionnaire, and the Jalowiec Coping Scale. The weight class of the women was determined as: normal weight-body mass index (BMI) of 18.5-24.9 kg/m, overweight-BMI of 25-29.9 kg/m, or obese-BMI > or = 30 kg/m. Statistical analysis conducted included Spearman's rho, Chi-square, and regression analysis. Confrontive coping was shown to be used more often to a "high" degree in normal-weight African American women than in overweight and obese African American women (chi = 24.024; P = .0001). Confrontive coping was the only independent predictor of weight class in a regression model that included perceived stress, life events, social support, and optimistic, self-reliant, and evasive coping strategies. Therefore, African American women who use confrontive coping to a high degree were more likely to confront problems, such as weight control issues, than those who use this coping strategy to a low or medium degree. 相似文献