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41.
Coronary artery anomalies are common among patients with tetralogy of Fallot. One hundred and thirty-five patients (80 males and 55 females) with tetralogy of Fallot who underwent repair between 1995 and 2002 were studied to determine the incidence of coronary anomalies in Iranian patients. Eight (5.9%) patients (4 males and 4 females) had a surgically relevant coronary artery anomaly: single coronary ostium in 5, origin of the left anterior descending artery from the right coronary artery in 2, and origin of the right coronary artery from the left coronary artery in 1. The surgical technique in 3 of these patients was repair of the ventricular septal defect with a transverse incision on the right ventricle, without damage to the coronary arteries. In another patient, an allograft aortic valve cylinder was inserted. In the other 4 patients with a single coronary ostium, placement of a limited transannular patch was adequate. Consideration of these anomalies during primary repair could decrease the risk of operation in such patients. However, it seems that the presence of anomalous coronary arteries does not affect incremental risk after surgical repair.  相似文献   
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BackgroundFrailty, a clinical state of vulnerability, is associated with subsequent adverse geriatric syndromes in the general population. We examined the long-term impact of frailty on geriatric outcomes among older patients with coronary heart disease.MethodsWe used the National Health and Aging Trends Study, a prospective cohort study linked to a Medicare sample. Coronary heart disease was identified by self-report or International Classification of Diseases (ICD) codes 1-year prior to the baseline visit. Frailty was measured using the Fried physical frailty phenotype. Geriatric outcomes were assessed annually during a 6-year follow-up.ResultsOf the 4656 participants, 1213 (26%) had a history of coronary heart disease 1-year prior to their baseline visit. Compared to those without frailty, subjects with frailty were older (ages ≥75: 80.9% vs 68.9%, P < 0.001), more likely to be female, and belong to an ethnic minority. The prevalence of hypertension, stroke, falls, disability, anxiety/depression, and multimorbidity were much higher in the frail, than nonfrail, participants. In a discrete time survival model, the incidence of geriatric syndromes during 6-year follow-up including 1) dementia, 2) loss of independence, 3) activities of daily living disability, 4) instrumental activities of daily living disability, and 5) mobility disability were significantly higher in the frail than in the nonfrail older patients with coronary heart disease.ConclusionIn patients with coronary heart disease, frailty is a risk factor for the accelerated development of geriatric outcomes. Efforts to identify frailty in the context of coronary heart disease are needed, as well as interventions to limit or reverse frailty status for older patients with coronary heart disease.  相似文献   
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Background: The efficacy of human recombinant erythropoietins (rHuEPOs) in the treatment of anemia with different etiologies is proven. Development of biosimilar rHuEPO products with lower cost and wider availability is important for the care of anemic patients. Objective: The aim of the present study was to determine the bioequivalence and safety of a biosimilar rHuEPO (Pastopoitin®) and compare it with the innovator product Eprex®, as a standard rHuEPO. Methods: One hundred and seven anemic patients on stable hemodialysis were recruited to this randomized double-blind comparative trial and assigned to either subcutaneous Pastopoitin (n = 50) or Eprex (n = 57). Each study group received rHuEPO at a dose of 80–120 IU/kg/week in 2–3 divided doses for a period of 3 months. Hematologic parameters including Hemoglobin, hematocrit, RBC, EBC, platelet, MCV, MCH and MCHC were checked every 2 weeks. Blood iron, ferritin, TIBC, creatinine, BUN and electrolytes (Na, K, Ca and P) were evaluated monthly over the 3 months. Results: A significant increase in hemoglobin, hematocrit and RBC was observed by the end of study in both Pastopoitin and Eprex groups (p < 0.001). However, these factors were not significantly different between the groups, neither at baseline nor at the end of study (p > 0.05). Likewise, the groups were comparable regarding MCV, MCH, MCHC, iron, ferritin, TIBC, creatinine, BUN and electrolytes at baseline as well as at the end of trial. Adverse events were not serious and occurred with the same frequency in the study groups. Conclusion: Pastopoitin showed comparable efficacy and safety profile with Eprex in anemic patients on hemodialysis. Hence, Pastopoitin may be considered as a rHuEPO with a lower cost and wider availability compared with the innovator product Eprex.  相似文献   
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The degree of admixture in Brazil between historically isolated populations is complex and geographically variable. Studies differ as to what the genetic and phenotypic consequences of this mixing have been. In Northeastern Brazil, we enrolled 522 residents of Salvador and 620 of Fortaleza whose distributions of self-declared color were comparable to those in the national census. Using the program Structure and principal components analysis there was a clear correlation between biogeographic ancestry and categories of skin color. This correlation with African ancestry was stronger in Salvador (r=0.585; P<0.001) than in Fortaleza (r=0.236; P<0.001). In Fortaleza, although self-declared blacks had a greater proportion of European ancestry, they had more African ancestry than the other categories. When the populations were analyzed without pseudoancestors, as in some studies, the relationship of ‘race'' to genetic ancestry tended to diffuse or disappear. The inclusion of different African populations also influenced ancestry estimates. The percentage of unlinked ancestry informative markers in linkage disequilibrium, a measure of population structure, was 3–5 times higher in both Brazilian populations than expected by chance. We propose that certain methods, ascertainment bias and population history of the specific populations surveyed can result in failure to demonstrate a correlation between skin color and genetic ancestry. Population structure in Brazil has important implications for genetic studies, but genetic ancestry is irrelevant for how individuals are treated in society, their health, their income or their inclusion. These track more closely with perceived skin color than genetic ancestry.  相似文献   
46.
Aim. Detection of methylation in the p16 gene, an inhibitor of cyclin D-dependent protein kinase, as a new tumor marker for early detection of esophageal squamous cell carcinoma (ESCC) in DNA derived from blood and serum. Method. A large family with clustering of ESCC was assessed in Khorasan province in northeastern Iran. The family had three histologically proven cases of ESCC in two consecutive generations and several other deceased cases with histories of ESCC. DNA from blood of 28 living family members in three consecutive generations, 30 sporadic ESCC cases (from serum, blood, and tumor tissues), and 30 healthy volunteers (from blood) were examined for the methylation status of p16 promoter using methylation-specific PCR (MSP). Results. Aberrant p16 promoter methylation was found in 64.3% (n=28) of ESCC family members and none (n=30) of our normal volunteers. Five of the 28 family members with esophageal cancer symptoms had negative endoscopy results for ESCC, while four of these members had p16 hypermethylation in their blood. The family members with negative endoscopy and positive p16 promoter methylation are being monitored closely for signs of ESCC development through regular check-ups and chromoendoscopies. In sporadic ESCC in northeastern Iran, 73.3% (n=30) of tumor tissue samples had p16 hypermethylation. Serum and blood samples from the same patients showed p16 hypermethylation in 26.6% and 43.3% of the samples, respectively. Conclusion. Aberrant p16 methylation may be a valuable diagnostic tool as a tumor marker for the early identification of individuals in high risk ESCC families.  相似文献   
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The effect of TSH, carbachol (CC), and ATP on intracellular calcium concentration ([Ca2+]i) in primary cultures of dog thyroid cells was examined using the fluorescent Ca2+ indicator fura-2. TSH caused an increase in [Ca2+]i at 37 C, but not 22 C, while it increased cAMP formation in these cells at both 22 and 37 C. CC and ATP increased [Ca2+]i at both 22 and 37 C. The CC-induced increase in [Ca2+]i was under muscarinic receptor control, and it was biphasic, with an initial spike followed by a sustained increase at a lower level. TSH and ATP were weaker agonists compared to CC, since maximal doses of TSH (100-500 mU/ml) and ATP (100-500 microM) increased [Ca2+]i by 40-70% over basal levels, compared to a 2- to 4-fold increase in [Ca2+] induced by maximal doses of CC (10-50 microM). The TSH-induced increase in [Ca2+]i was transient, returning to basal levels within 1-2 min after application of the agonist. All three agents were able to transiently increase [Ca2+]i to be internal stores. In the presence of the inorganic Ca2+ channel blockers La3+, Ni2+, and Co2+, the peak [Ca2+]i change was little affected, while the persistent response to CC and ATP was blocked, indicating dependence of this phase on influx of Ca2+. Paradoxically, these channel blockers abolished the effect of TSH on [Ca2+]i. TSH stimulation of cAMP formation was also inhibited 80-90% by these blockers, but not in Ca2+-free/EGTA buffer. These results suggest that the Ca2+ channel blockers may have actions in addition to inhibition of Ca2+ entry in these cells. TMB-8 [8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate HCl] specifically blocked both the initial and sustained increase induced by CC, while having no effect on ATP or TSH-induced [Ca2+]i, suggesting that TMB-8 may not be a general antagonist of Ca2+ mobilization. Activators of protein kinase-C, such as phorbol esters or an analog of diacylglycerol, inhibited the [Ca2+]i rise induced by all the three agonists used, indicating a regulatory role of protein kinase-C activation on [Ca2+]i in these cells. In FRTL-5 cells, [Ca2+]i was also increased by TSH and ATP, but not by CC. ATP, however, was a more effective agonist than in dog thyroid cells, while TSH increased [Ca2+]i by a similar magnitude in both cell types. The results of the present study demonstrate that TSH, albeit of lesser potency than CC, increases [Ca2+]i by causing intracellular Ca2+ mobilization in cultured dog thyroid cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. The sensor was fabricated from a 4H-SiC (0001) wafer, using a 1 μm thick p-type epilayer with a concentration of 1018 cm−3. Taking advantage of the four-terminal configuration, the sensor can eliminate the need for resistance-to-voltage conversion which is typically required for two-terminal devices. The van der Pauw sensor also exhibits an excellent repeatability and linearity with a significantly large output voltage in induced strain ranging from 0 to 334 ppm. Various sensors aligned in different orientations were measured and a high sensitivity of 26.3 ppm−1 was obtained. Combining these performances with the excellent mechanical strength, electrical conductivity, thermal stability, and chemical inertness of 4H-SiC, the proposed sensor is promising for strain monitoring in harsh environments.

This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices.  相似文献   
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