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72.
The mechanisms relating pulse pressure to cardiovascular outcome may include surrogacy for coronary disease severity. Although pulse pressure is typically measured at the brachial artery, central pulse pressure and its principal determinant, large-artery stiffness, may relate more closely to disease severity. This study aimed to determine the relationships between large-artery stiffness and carotid and brachial blood pressures and coronary artery disease severity. One hundred fourteen male patients with coronary artery disease (age 60+/-8 years, mean+/-SD) and 57 age-matched healthy male controls (age 59+/-9 years) were recruited. Patients were classified into 2 groups based on the magnitude of their maximum coronary stenosis: moderate (50% to 89%) and severe (>/=90%). Large-artery stiffness was assessed as systemic arterial compliance and carotid-femoral pulse wave velocity. Mean pressure was not different between the 3 groups. Systemic compliance and carotid pulse pressure were significantly different between all 3 groups, with compliance lowest and pressure highest in the severe group (P<0.05). Pulse wave velocity was higher in patients with severe stenosis than in those with moderate stenosis (P<0.01) and those in the control group (P<0.001). Brachial pulse pressure was higher in patients than in controls (P<0.05), but there was no difference between the 2 disease groups. In separate multivariate analyses, carotid pressures and systemic arterial compliance were determinants of coronary artery disease severity, independent of age, smoking status, body mass index, mean arterial pressure, heart rate, cholesterol levels (total, LDL, and HDL), triglycerides, and beta-antagonist and lipid-lowering therapy (P<0.001), whereas brachial pressures and pulse wave velocity were not. In conclusion, central blood pressures and systemic arterial compliance are more sensitive markers of coronary artery disease severity than brachial pressures. 相似文献
73.
Outcome of foot injuries in multiply injured patients 总被引:2,自引:0,他引:2
Stiegelmar R McKee MD Waddell JP Schemitsch EH 《The Orthopedic clinics of North America》2001,32(1):193-204, x
In the past, foot injuries in patients with multiple trauma were thought to be of lesser importance than fractures of long bones. In one prospective study from the authors' institutions, however, multiple-trauma patients with foot injuries were shown to have a poorer functional outcome compared with matched controls. To address these concerns, this article has two parts. The first part is an overview of general principles in the treatment of foot injuries in polytrauma patients. The treatment of specific injuries is beyond the scope of this article, but an approach is highlighted that can be remembered when decisions are made regarding these severely injured patients. The second part reviews the findings from the authors' study, focusing on functional outcomes of multiple-trauma patients with foot injuries. 相似文献
74.
Carolyn V. Kirschner MD Jose M. Alanis-Amezcua MD Victorino G. Martin MD Nic Luna HT Eileen Morgan MPA Jih-Jing Yang PhD Edgardo L. Yordan MD Funded by a Lutheran General HealthSystem Clinical Research Support Grant. 《American journal of obstetrics and gynecology》1996,174(6):1879-1884
OBJECTIVE: Tumor angiogenesis is believed to be a prognostic indicator associated with tumor growth and metastasis. Studies of angiogenesis in breast, prostate, and lung cancer, as well as melanoma, have shown that neovascularization correlates with the likelihood of metastasis and recurrences. The purpose of this study was to evaluate microvessel density as a prognostic factor in endometrial cancer. METHODS: Between 1980 and 1991 the tumor registry identified 25 patients with a diagnosis of recurrent endometrial cancer. These patients were matched with 25 patients with nonrecurrent disease for age, stage, grade, and treatment. The histologic slides of the 50 patients were reviewed. The paraffin blocks were obtained, and the area of the deepest myometrial invasion was selected for staining. The microvessels within the invasive cancer were highlighted by means of immunocytochemical staining to detect factor VIII - related antigen. Microvessels were counted by two investigators who were blinded to the patients' clinical status. Survival data were analyzed with Kaplan-Meier survival curves. RESULTS: Microvessel count was related to likelihood of recurrence, although this trend did not reach statistical significance. Patients with tumors of low capillary density had a mean survival time of 123 months. Patients with tumors of high capillary density had a mean survival time of 75 months (p = 002). Among patients with recurrent disease, those with a low capillary count survived a mean of 64 months. Patients with recurrent disease with tumors of high capillary density survived a mean of 45 months (p = 0.002). CONCLUSION: Angiogenesis factor correlates with survival in endometrial carcinoma. (Am J Obstet Gynecol 1996;174:1879-84.) 相似文献
75.
Rationale Animal models of anxiety such as the four-plates test (FPT) enable the detection of an anxiolytic effect not only of benzodiazepines (BZDs) but also of other non-BZD anxiolytic compounds such as the antidepressants paroxetine and venlafaxine. Retesting mice in animal models of anxiety markedly alters the behavioural profile of various drugs.Objectives The aim of this study was first to investigate the function of GABAA/BZD receptor and passive avoidance acquisition in the FPT test–retest. The second aim of this study was to evaluate the capacity of the FPT to discriminate BZDs from other non-BZD anxiolytics in experienced mice.Methods The FPT was performed in naive and experienced mice (submitted to the test 24 h previously). The drugs studied were two BZDs, diazepam (1 mg/kg) and alprazolam (0.25 mg/kg); flumazenil, a GABAA receptor antagonist (8 mg/kg); atropine sulphate, a muscarinic cholinergic receptor antagonist (4 mg/kg) known for its amnesic properties; paroxetine, a selective serotonin reuptake inhibitor (4 and 8 mg/kg); venlafaxine, a serotonin and noradrenalin reuptake inhibitor (4 and 16 mg/kg); and DOI, a 5-HT2A agonist (1 mg/kg).Results Our results reveal an increase of anxiety (decrease of punished passages) in saline-experienced mice. Diazepam, alprazolam, paroxetine and venlafaxine did not prevent the increase in anxiety during retest, revealing a passive avoidance acquisition. Flumazenil did not modify the anxiogenic-like behaviour of experienced mice. In contrast, atropine seems to oppose the increase of anxiety; however, its effect is weak and disputable. DOI was the only anxiolytic compound able to oppose the decrease of punished passages of experienced mice.Conclusion Anxiogenic behaviour on retesting indicates aversive learning. The protocol test–retest is unable to discriminate between the anxiolytic effect of BZDs from that of paroxetine or venlafaxine. However, this modified model may constitute a new tool to investigate other neural pathways implicated in anxiety. 相似文献
76.
All total joint replacements generate wear debris; yet, some implant prostheses fail while others survive despite the presence of ultrahigh molecular weight polyethylene particulate. It was hypothesized that patients with failed hip implants who have osteolysis will secrete higher inflammatory cytokines than patients receiving total joint replacements. Our study evaluated the peripheral blood monocyte response to varying polyethylene particle volume ratios through cytokine quantification in two patient populations: patients having revision surgery for failed total hip replacements (failed implant group) and patients having primary total hip surgery for osteoarthritis of the hip (primary implant group). We observed elevation of all three proinflammatory cytokines tested (interleukin-6, interleukin-1, and tumor necrosis factor-alpha) in response to polyethylene particulate challenge when compared with the controls in both patient groups. The population with failed implants also had a higher absolute cytokine response to polyethylene exposure compared with the control patients having primary implants. These findings suggest that patients with failed implants have a greater inflammatory cytokine response to polyethylene than seen in patients with primary implants. 相似文献
77.
Bullying and symptoms among school-aged children: international comparative cross sectional study in 28 countries 总被引:1,自引:1,他引:0
Due P Holstein BE Lynch J Diderichsen F Gabhain SN Scheidt P Currie C;Health Behaviour in School-Aged Children Bullying Working Group 《European journal of public health》2005,15(2):128-132
BACKGROUND: There have been no large-scale international comparisons on bullying and health among adolescents. This study examined the association between bullying and physical and psychological symptoms among adolescents in 28 countries. METHODS: This international cross-sectional survey included 123,227 students 11, 13 and 15 years of age from a nationally representative sample of schools in 28 countries in Europe and North America in 1997-98.The main outcome measures were physical and psychological symptoms. RESULTS: The proportion of students being bullied varied enormously across countries. The lowest prevalence was observed among girls in Sweden (6.3%, 95% CI: 5.2-7.4), the highest among boys in Lithuania (41.4%, 95% CI 39.4-43.5). The risk of high symptom load increased with increasing exposure to bullying in all countries. In pooled analyses, with sex stratified multilevel logistic models adjusted for age, family affluence and country the odds ratios for symptoms among students who were bullied weekly ranged from 1.83 (95% CI 1.70-1.97) to 2.11 (95% CI 1.95-2.29) for physical symptoms (headache, stomach ache, backache, dizziness) and from 1.67 (95% CI 1.55-1.78) to 7.47 (95% CI 6.87-8.13) for psychological symptoms (bad temper, feeling nervous, feeling low, difficulties in getting to sleep, morning tiredness, feeling left out, loneliness, helplessness). CONCLUSION: There was a consistent, strong and graded association between bullying and each of 12 physical and psychological symptoms among adolescents in all 28 countries. 相似文献
78.
Enostoses, osteomas, osteopoikilosis, osteopathia striata, and melorheostosis may simulate other diseases. However, the findings on imaging usually are characteristic enough to indicate the correct diagnosis. 相似文献
79.
Garnett KE Chapman P Chambers JA Waddell ID Boam DS 《Journal of molecular endocrinology》2005,35(1):13-25
80.