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OBJECTIVE: Platelet factor 4 (PF-4) is a critical alpha chemokine in inflammation and injury responses, with multiple effects upon cellular activities. Discrete peptide sequences of the PF-4 molecule have been shown to retain biological activity. Our aim was to examine the influence of the PF-4 derived octapeptide (CT-112; TTSQVRPR) on type II collagen induced arthritis in mice, to determine if this peptide exhibited antiinflammatory properties. METHODS: DBA/1 mice were treated with CT-112 from either the time of immunization with type II collagen or from the initial onset of arthritis. RESULTS: CT-112 both prevented the development of arthritis in mice treated prophylactically and reduced progression of disease in animals treated therapeutically, and was active when delivered by either subcutaneous injection or oral gavage. No marked immunosuppressive effects were observed during CT-112 treatment, with only moderate decrease in antibody levels and mitogen responses. A significant reduction of the circulating levels of IL-1 was a consistent finding in mice treated therapeutically with CT-112. CONCLUSION: These data suggest PF-4 derived octapeptide exerts antiinflammatory effects of experimental arthritis in mice.  相似文献   
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The way data is presented can seriously affect the ease with which it can be understood. The objectives and results of a survey of different types of presentation are given. Some psychological aspects of the problem are analysed.  相似文献   
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The issue of generic scaling laws able to adequately predict (within better than 20%) cratering in semi-infinite targets and perforations through finite thickness targets was revisited. The approach used was to apply physical logic for hydrodynamics in a consistent manner able to account for chunky-body impacts such that the only variables needed are those directly related to known material properties for both the impactor and target. The analyses were compared and verified versus CTH hydrodynamic code calculations and existing experimental data. Comparisons with previous scaling laws were also performed to identify which (if any) were good for generic purposes. This paper is a short synopsis of the full report [1] available through the NASA Langley Research Center, LDEF Science Office.  相似文献   
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Mortality in 11 secular kibbutzim between 1970 and 1985 was nearly twice that of 11 matched religious kibbutzim. A cross-sectional study was undertaken in 1991 in 10 of these settlements, 5 religious and 5 secular, to determine whether differences in risk factors could explain the unequal survival. These comprised physical, physiologic and biochemical measurements, health-relevant behaviors and psychosocial variables. This report addresses the psychosocial aspect of the study, which included assessment of sense of coherence, hostility, satisfaction with self, work-related stress, social supports and social contacts using self-administered questionnaires. The response rate among the sample of men and women, aged 35-64 years, was 76% (437 respondents, 208 men and 229 women). Analysis of variance and logistic regression (the latter comparing the upper or lower fourths of the distribution vs. the rest) were used. Religious kibbutz members reported a higher sense of coherence (odds ratio = 1.58, 95% CI 1.02 to 2.46) and a lower level of hostility (odds ratio = 0.49, 95% CI 0.33 to 0.75) than their secular counterparts. Findings for satisfaction with self and work-related stress were inconsistent; there were significant interactions between religious affiliation, sex and age. Younger women reported less satisfaction with self and higher work-related stress than the other age-sex groups in both types of kibbutz. There was no difference in social support or frequency of social contact between religious and secular kibbutzim. Voluntary work was more frequent among the religious kibbutzim. The findings are consistent with an interpretation that Jewish religious observance may enhance the formation of certain protective personality characteristics. Membership in a cohesive religious kibbutz community may increase host resistance to stressors and thereby promote overall well-being and a positive health status. This could reflect an interplay of individual and collective attributes of religion.  相似文献   
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BACKGROUND: The association of serum lipids with coronary heart disease has been studied extensively in middle-aged men and, to a lesser extent, in similar women. Less well defined are lipid variables predictive of CHD in individuals of age > or = 60 years. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program recruited 4736 persons (mean age, 72 years; 14% were black; and 43% were men). Mean systolic and diastolic blood pressures were 170 and 77 mm Hg, respectively. Baseline mean total cholesterol was 6.11 mmol/L (236 mg/dL); HDL cholesterol, 1.39 mmol/L (54 mg/dL); and non-HDL cholesterol, 4.72 mmol/L (182 mg/dL). Triglyceride levels were 1.62 mmol/L (144 mg/dL) for fasting participants and 1.78 mmol/L for the total group. LDL cholesterol, estimated in fasting samples with triglycerides of < 4.52 mmol/L, averaged 3.98 mmol/L (154 mg/dL). Mean follow-up was 4.5 years. In multivariate Cox regression analyses, baseline total, non-HDL, and LDL cholesterol levels and the ratios of total, non-HDL, and LDL to HDL cholesterol were significantly related to CHD incidence. HDL cholesterol and triglycerides were not significant in these analyses. In fasting participants with triglyceride levels of < 4.52 mmol/L, a 1.03 mmol/L (40 mg/dL) higher baseline total, non-HDL, or LDL cholesterol was associated with a 30% to 35% higher CHD event rate. CONCLUSIONS: The results of this study support the concept that serum lipids are CHD risk factors in older Americans.  相似文献   
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A prospective study of 66 consecutive patients with cardiac wounds seen over a 27-month period is reported. No patient was excluded. Patients were stratified by injury mechanism and by physiologic scoring at admission using the cardiovascular-respiratory elements of the Trauma Score (CVRS). Admission cardiac rhythm was obtained in patients with a CVRS of 0 and a Glasgow Coma Scale (GCS) score of 3. Information concerning the anatomic extent of the cardiac wound, the presence or absence of tamponade, and the degree of injury to other structures was also collected prospectively. Seventy percent of the cardiac wounds were caused by gunshots. The probability of successful resuscitation was significantly related to mechanism of injury and physiologic condition on arrival. Among patients arriving with a CVRS of 0 and a GCS score of 3, survival correlated with cardiac rhythm. Pericardial tamponade did not prove to be an independent predictor of early survival. The presence of tamponade was statistically linked to the mechanism of injury. Transport by non-official conveyance was associated with a higher CVRS on arrival. Intoxication with alcohol or cocaine had no evident effect on resuscitation probability.  相似文献   
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