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61.
62.
Takahisa Okano Matthew D. Horton Gary G. Fermanis David A. Horton 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):437-439
We report a re-do case of severe aortic valve stenosis due to pannus formation 29 years after an aortic Starr-Edwards caged-ball
valve implantation. A huge shelf of calcified and thick pannus tissue below the valve had reduced the already small orifice
by at least a third in surface area. The explanted Starr-Edwards valve revealed no mechanical or structural failure. Early
detection and treatment of pannus outgrowth is essential in order to prevent life-threatening prosthetic valve malfunctions. 相似文献
63.
64.
T Matthew Shields Charles H Hennekens 《Endocrinology & Metabolism Clinics of North America》2004,33(3):577-93, vii
Cardiovascular disease (CVD), which includes myocardial infarction(MI), stroke, and peripheral vascular disease, remains the leading cause of death in the United States and in most developed countries. In the United States today, 25% of patients have metabolic syndrome-including those who have had a prior occlusive vascular disease event, those who are having an acute MI or ischemic stroke, and finally, the largest segment of the population,namely those who have not yet experienced a clinical CVD, but whose risks are substantial (10-year risk 10%). This article reviews the totality of evidence for aspirin in the treatment and prevention of CVD and emphasizes its importance as adjunctive therapy for patients with metabolic syndrome. 相似文献
65.
66.
Actin-free Gc globulin: a rapidly assessed biomarker of organ dysfunction in acute liver failure and cirrhosis. 总被引:2,自引:0,他引:2
Charalambos G Antoniades Philip A Berry Matthew Bruce Timothy J S Cross Andrew J Portal Munther J Hussain William Bernal Julia A Wendon Diego Vergani 《Liver transplantation》2007,13(9):1254-1261
Reductions in serum levels of Gc globulin, a hepatically synthesized component of the extracellular actin scavenger system responsible for complexing circulating actin and attenuating intravascular microthrombus formation, are associated with poor outcome in acute liver failure. Clinically applicable assays of the important actin-free fraction (Af-Gc) have not been available until now. We measured actin-free Gc globulin levels with a novel, rapid assay in 61 cases of acute liver failure (ALF) and in 91 patients with cirrhosis (40 of whom were clinically unstable with extrahepatic organ dysfunction), and studied associations with liver dysfunction, extrahepatic organ dysfunction, indices of disseminated coagulation, and outcome. Reductions in Af-Gc levels mirrored hepatic dysfunction and organ dysfunction in both groups, and discriminated patients with poor prognosis from those with good prognosis in the ALF cohort. Levels were lowest in patients with ALF (10% of control values), but levels were also markedly reduced in both unstable (28%) and stable (44%) patients with cirrhosis. Associations with markers of disseminated intravascular coagulation were seen in both groups, most notably in the cirrhosis cohort, supporting a pathophysiological role for reduced Af-Gc in the evolution of organ dysfunction. In acetaminophen-induced ALF, Af-Gc identified patients with poor prognosis as well as did the Acute Physiology and Chronic Health Evaluation (APACHE II) score (area under the receiver operating characteristic curve, 0.7), and in cirrhosis, Af-Gc was an independent predictor of mortality by multifactorial analysis. In conclusion, the importance of Af-Gc reductions in the development of multiple organ dysfunction in ALF and cirrhosis is highlighted, probably resulting from reduced hepatic production and peripheral exhaustion of this arm of the extracellular actin scavenger system. 相似文献
67.
Matthew Rispoli 《J. Speech Lang. Hear. Res.》2003,46(4):818-830
The sentence production capabilities of young children undergo major changes during the same period in which grammar develops. This article reports data from a cross-sectional sample of 52 children between the ages of 1;10 (years; months) and 4;0, and looks specifically at the dichotomy between stalls, sentence disruptions that are the result of glitches in sentence production, and revisions, sentence disruptions that involve self-monitoring and the rapid replacement of words or morphosyntactic alternatives. It was found that revision rate increased with level of grammatical development, but that stall rate was not related to grammatical development. These results indicate that children's capacities for self-monitoring and maintenance of multiple linguistic alternatives increase during the period of grammatical development. 相似文献
68.
Three years of alendronate treatment results in similar levels of vertebral microdamage as after one year of treatment. 总被引:3,自引:0,他引:3
Three years of daily alendronate treatment increases microdamage in vertebral bone but does not significantly increase it beyond levels of microdamage found after 1 yr of treatment. This suggests microdamage accumulation peaks during the early period of bisphosphonate treatment and does not continue to accumulate with longer periods of treatment. INTRODUCTION: Clinically relevant doses of alendronate increase vertebral microdamage by 4- to 5-fold in skeletally mature beagles after 1 yr of treatment. The goal of this study was to determine whether microdamage would continue to accumulate with 3 yr of alendronate treatment in an intact beagle dog model. MATERIALS AND METHODS: One-year-old female beagles were treated with daily oral doses of vehicle (VEH, 1 ml/kg/d) or alendronate (ALN, 0.2 or 1.0 mg/kg/d) for 3 yr. These ALN doses were chosen to approximate, on a milligram per kilogram basis, those used to treat osteoporosis (ALN0.2) and Paget's disease (ALN1.0). Microdamage accumulation, static and dynamic histomorphometry, densitometry, and mechanical properties of lumbar vertebrae were assessed. Comparisons were made among the three groups treated for 3 yr and also within each treatment group to animals treated under the same conditions for 1 yr. RESULTS: Overall microdamage accumulation (crack surface density) was not significantly higher in animals treated for 3 yr with either dose of ALN, whereas crack density increased significantly (100%; p < 0.05) with the higher dose of ALN compared with VEH. Both ALN doses significantly suppressed the rate of bone turnover (-60% versus VEH). There was no difference among groups for any of the structural biomechanical properties-ultimate load, stiffness, or energy absorption. However, when adjusted for areal BMD, ALN-treated animals had significantly lower energy absorption (-20%) compared with VEH. Toughness, the energy absorption capacity of the bone tissue, was significantly lower than VEH for both ALN0.2 (-27%) and ALN1.0 (-33%). Compared with animals treated for 1 yr, there was no significant difference in microdamage accumulation for either ALN dose. VEH-treated animals had significantly lower bone turnover (-58%) and significantly higher levels of microdamage (+300%) compared with values in 1-yr animals. Toughness was significantly lower in animals treated for 3 yr with ALN1.0 (-18%) compared with animals treated for 1 yr, whereas there was no difference in toughness between the two treatment durations for either VEH or ALN0.2. CONCLUSIONS: Although 3 yr of ALN treatment resulted in higher microcrack density in vertebral trabecular bone compared with control dogs, the amount of microdamage was not significantly higher than animals treated for 1 yr with similar doses. This suggests that bisphosphonate-associated increases in microdamage occur early in treatment. Because toughness continued to decline significantly over 3 yr of treatment at the higher ALN dose, decreases in toughness are probably not dependent on damage accumulation. 相似文献
69.
Clinical risk factors for fractures in multi-ethnic women: the Women's Health Initiative. 总被引:1,自引:0,他引:1
Jane A Cauley Lieling Wu Nina S Wampler Janice M Barnhart Matthew Allison Zhao Chen Rebecca Jackson John Robbins 《Journal of bone and mineral research》2007,22(11):1816-1826
To identify risk factors for fractures in multi-ethnic women, we studied 159,579 women enrolled in the Women's Health Initiative. In general, risk factors for fractures were similar across ethnic groups. However, irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. INTRODUCTION: Fracture rates tend to be lower in minority women, but consequences may be greater. In addition, the number of fractures is expected to increase in minority women because of current demographic trends. There are limited prospective data on risk factors for fractures in minority women. MATERIALS AND METHODS: We studied 159,579 women 50-79 yr of age enrolled in the Women's Health Initiative. Information on risk factors was obtained by questionnaire or examination. Nonspine fractures that occurred after study entry were identified over an average follow-up of 8 +/- 2.6 (SD) yr. RESULTS: Annualized rates (%) of fracture in whites, blacks, Hispanics, Asians, and American Indians were 2.0, 0.9, 1.3, 1.2, and 2.0, respectively. Significant predictors [HR (95% CI)] of fractures by ethnic group were as follows: blacks: at least a high school education, 1.22 (1.0, 1.5); (+) fracture history, 1.7 (1.4, 2.2); and more than two falls, 1.7 (1.9, 2.0); Hispanics: height (>162 cm), 1.6 (1.1, 2.2); (+) fracture history, 1.9 (1.4, 2.5); more than two falls, 1.8 (1.4, 2.3); arthritis, 1.3 (1.1, 1.6); corticosteroid use, 3.9 (1.9, 8.0); and parental history of fracture, 1.3 (1.0, 1.6); Asians: age (per 5 yr), 1.2 (1.0, 1.3); (+) fracture history, 1.5 (1.1, 2.0); current hormone therapy (HT), 0.7 (0.5, 0.8); parity (at least five), 1.8 (1.1, 3.0); more than two falls, 1.4 (1.1, 1.9); American Indian: (+) fracture history, 2. 9 (1.5, 5.7); current HT, 0.5 (0.3, 0.9). Women with eight or more risk factors had more than a 2-fold higher rate of fracture compared with women with four or fewer risk factors. Two ethnicity x risk factor interactions were identified: age and fall history. CONCLUSIONS: Irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. 相似文献
70.