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991.
A body of evidence indicates that masked hypertension is a significant predictor of cardiovascular disease, but how to identify these patients is still a matter of dispute. Data obtained in several cross-sectional studies have demonstrated that masked hypertension is associated with increased left ventricular mass index and carotid intima-media thickness, and impaired large artery distensibility. Furthermore, in longitudinal studies, masked hypertension was a strong predictor of cardiovascular morbidity and mortality. Several factors that can selectively raise ambulatory blood pressure increase the likelihood of having masked hypertension. These include younger age, smoking, alcohol use, contraceptive use in women, sedentary habits and central obesity. In addition, masked hypertension is more common in individuals with high-normal clinic blood pressure or transiently elevated blood pressure. Increased reactivity to daily life stressors and behavioural factors are other important predictors of masked hypertension. In clinical practice, masked hypertension should be searched for in individuals who are more likely to have this condition or are at increased risk of cardiovascular events including those with coronary, cerebrovascular or kidney disease, patients with diabetes and individuals with a high cardiovascular risk profile. To determine whether the use of ambulatory blood pressure monitoring is cost-effective in these individuals, further research is needed.  相似文献   
992.
The study investigated the use of, attitudes towards, and adherence to motorcycle helmets in a group of adolescents. A random sample of 412 adolescents (14–19 years old) attending randomly selected public secondary classes in Catanzaro (Italy) received a questionnaire consisting of questions on socio-demographics, patterns of motorcycle use, frequency of helmet use, helmet use by adult family members and close friends who are motorcyclists, attitudes towards helmet use and number of traffic-related motorcycle accidents in the last year. A total of 387 adolescents participated. The frequency of self-reported helmet use as a driver of the motorcycle or as the passenger was 34.7% and 33.7% respectively. Routine helmet use was greater for adolescents from households in which at least one family member wore a helmet, for youths who agreed that helmet use should be mandatory, and for those who did not experience an accident in the past year. Regression analysis of the attitude models indicated that the younger the age, the more willing an adolescent would be to believe that helmet use reduced the risk of head injuries and the positive attitude that helmet use should be mandatory was higher in younger adolescents and in those who had no road accident within the past year. A total of 17% reported that they had an accident during the last 12 months of the study period and 30 of them presented motorcycle-related injuries. Conclusion:The development of programmes on helmet use starting as early as primary school is strongly needed.Preliminary results of this study were presented at the 3rd International Conference on Traffic and Transport Psychology, Nottingham, UK, September 5–9, 2004.  相似文献   
993.
994.
Coronary arterial inflammation in acute Kawasaki disease (KD) is characterized by transmural infiltration of CD8 T lymphocytes, suggesting that CD8 T lymphocyte cytotoxic activity may be important in the pathogenesis of coronary arterial damage in acute KD. We performed immunohistochemistry for the cytotoxic proteins perforin and granzyme B on paraffin-embedded, formalin-fixed coronary artery aneurysm tissue from 6 children who died in the acute stage of KD. Neither perforin nor granzyme B was detected in the KD coronary aneurysm wall. We speculate that the etiologic agent of KD interferes with expression of these cytotoxic proteins by CD8 T lymphocytes, prolonging inflammation in the arterial wall and leading to coronary artery aneurysm formation.  相似文献   
995.
Chronic granulomatous disease (CGD) is a rare genetically determined immunodeficiency. Neutrophils from CGD patients show a defective killing of phagocytosed fungi and bacteria, due not only to an impairment in oxidative burst, but also to absence of normal pH value within phagocytic vacuole following phagocytosis. Because a weak base such as amantadine could potentially reverse these pH abnormalities, the authors used this drug to treat 2 CGD patients. They observed modifications of both phagosomal pH and killing activity on their neutrophils compared to those of healthy controls. Since the drug has been employed, the patients have not developed new infections, suggesting a role of amantadine as a part of CGD prophylactic regimen. These results suggest the opportunity of testing the drug in larger studies.  相似文献   
996.
OBJECTIVE: Sexually transmitted infections (STI) among adolescents continue to be an important public health problem for many industrialized and developing countries. This study evaluated knowledge and behaviour in adolescents regarding prevention of STI. METHODS: Information was obtained by using self-reported questionnaire from a random sample of 644 undergraduate students at university and at public high schools aged 14-20 years in Catanzaro (Italy). RESULTS: Only 14.2% of respondents knew about the main STI and that they can be transmitted through sexual intercourse with HIV seropositive partners; this knowledge was significantly higher among adolescents who had had a higher number of sexual partners in their lifetime and who had received information from physicians about STI. A total of 33.8% reported having had sexual intercourse at least once and the mean age at first intercourse was 16 years. Older males and adolescents with employed mothers were more likely to have reported having had a sexual experience. The prevalence of using condoms every time during sexual intercourse was 51.8% and such behaviour was more likely in younger adolescents and males. The prevalence of condom use on the last occasion of sex was 71.9%. Younger adolescents, those with a higher perception of the risk of contracting STI and those with lesser knowledge about STI were independent predictors for using condoms. The mean total score of the respondents' perception of a risk of contracting STI was 5.8. CONCLUSIONS: Evidence to develop and implement strategies with the hope of improving adolescents' level of knowledge and reducing unsafe sexual practices.  相似文献   
997.
OBJECTIVE: Fibromyalgia (FM) is a syndrome characterized by widespread musculoskeletal pain. Symptoms of orthostatic intolerance may also be present, suggesting underlying abnormalities of cardiovascular neural regulation. We tested the hypothesis that FM is characterized by sympathetic overactivity and alterations in cardiovascular autonomic response to gravitational stimulus. METHODS: Sixteen patients with primary FM and 16 healthy controls underwent electrocardiography examination, finger blood pressure, respiration, and muscle sympathetic nerve activity (MSNA) recordings at rest and during stepwise tilt test, up to 75 degrees . The autonomic profile was assessed by MSNA, plasma catecholamine, and spectral indices of cardiac sympathetic (LFRR in normalized units, NU) and vagal (HFRR both in absolute and NU) modulation and of sympathetic vasomotor control (LFSAP) computed by spectrum analysis of RR and systolic arterial pressure (SAP) variability. Arterial baroreflex function was evaluated by the SAP/RR spontaneous-sequences technique, the index a, and the gain of MSNA/diastolic pressure relationship during stepwise tilt test. RESULTS: At rest, patients showed higher values of heart rate, MSNA, LFRR NU, LF/HF, LFSAP, and reduced HFRR than controls. During tilt test, lack of increase of MSNA, less decrease of HFRR, and excessive rate (44%) of syncope were found in patients, suggesting reduced capability to enhance the sympathetic activity to vessels and withdraw the vagal modulation to sino-atrial node. Baroreflex function was similar in both groups. CONCLUSION: Patients with FM have an overall enhancement of cardiovascular sympathetic activity while recumbent. Lack of increased sympathetic discharge to vessels and decreased cardiac vagal activity characterize their autonomic profile during tilt test, and might account for the excessive rate of syncope.  相似文献   
998.
The direct expression and production of the critical osteoclastogenic factor, the receptor activator of NF-kB ligand (RANKL), is a matter of controversy. In this study we definitively demonstrate by both qualitative and quantitative polymerase chain reaction analysis that human myeloma cells do not express significant levels of RANKL mRNA or produce RANKL able to stimulate osteoclast formation.  相似文献   
999.
We report the successful use of bortezomib to treat a patient with multiple myeloma (MM) who had extramedullary relapse (paraspinal and thoracic masses and multiple cranial nerve palsy) after autologous and non-myeloablative allogeneic hematopoietic stem cell transplantation (HSCT).  相似文献   
1000.
Congenitally corrected transposition of the great arteries (ccTGA) is a rare anomaly characterized by atrioventricular and ventriculo-arterial discordance and several other malformations that eventually lead to heart failure. We describe the case of a 53-year-old woman with ccTGA and aortic insufficiency who was a candidate for heart transplantation due to end-stage congestive heart failure. Her condition deteriorated before a suitable donor heart could be found; therefore, we placed a left ventricular assist device in the right (systemic) ventricle. Concomitantly, we removed the aortic (systemic) valve, closed the aortic annulus with a bovine pericardial patch, and repaired the mitral valve. The patient recovered uneventfully and was discharged from the hospital 2 months postoperatively. She underwent cardiac transplantation approximately 6 months later and continued to do well after 18 months.  相似文献   
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