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The prevalence of Brugada's electrocardiographic (ECG) pattern in 7,022 male adolescents in the seventh grade was determined, and the same subjects were reexamined 3 years later, while in tenth grade. Two subjects (0.03%) and 7 subjects (0.10%) showed Brugada's ECG pattern by the conventional criterion (J point or ST-segment >/=0.1 mV in leads V(1) to V(3)), and no subjects (0%) and 2 subjects (0.03%) fulfilled the recent criterion (J point or ST-segment >/=0.2 mV) in the seventh and tenth grades, respectively, indicating that Brugada's ECG pattern begins to appear during junior high school and increases until late adulthood.  相似文献   
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Gastric inhibitory polypeptide (GIP) has considerable structural homology with glucagon, which is known to increase liver blood flow. We compared the effects of GIP on portal venous and hepatic arterial flow with those of glucagon in conscious dogs. Injection of GIP significantly increased portal venous flow in a dose-related manner (by 7%, 15%, and 46% at doses of 1, 100, and 500 pmol/kg, respectively). The increase in portal venous flow induced by GIP and glucagon was comparable; however, the increase in portal venous flow after GIP injection reached its peak significantly earlier than that after glucagon injection. Hepatic arterial flow decreased after GIP injection (by 17%, 21%, and 35% at doses of 1, 100, and 500 pmol/kg, respectively), whereas it was not altered by glucagon. Thus, GIP causes significant changes in both portal venous and hepatic arterial flow in conscious dogs. Although structurally related, GIP and glucagon may influence liver blood flow through different mechanisms.Supported by a grant from the Ministry of Education, Japan (No. A-02404052)  相似文献   
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BackgroundPlatelet function testing (PFT) in patients treated with P2Y12 inhibitors has been widely evaluated for the prediction of stent thrombosis, myocardial infarction, and bleeding events following percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS). Thus, PFT-guided treatment could positively affect patient outcomes. Data regarding clinical parameters for predicting platelet reactivity in ACS patients are limited. Therefore, our study aims to evaluate CHADS2 and CHA2DS2-VASc scores as predictors for platelet reactivity in ACS patients.MethodsTwo hundred and ninety-one consecutive patients who underwent PCI and were treated with aspirin and clopidogrel due to ACS were tested for their CHADS2, CHA2DS2-VASc scores and platelet reactivity using adenosine diphosphate (ADP)-induced aggregation (conventional aggregometry). Patients were classified into groups according to their CHADS2 and CHA2DS2-VASc scores. Low-risk group (0–1 score) for CHADS2 and CHA2DS2-VASc scores and high-risk group (2–6, 2–9) for CHADS2 and CHA2DS2-VASc scores, respectively. Furthermore, platelet reactivity in each group were compared (low CHADS2 group vs high CHADS2 group, and low CHA2DS2-VASc vs high CHA2DS2-VASc). Platelet reactivity was defined as low platelet reactivity (<19 U), optimal platelet reactivity [(OPR); 19–46 U], and high on-treatment platelet reactivity [(HPR); >46 U]. Thereafter receiver operating characteristic curve analysis was conducted to verify whether CHADS2 and CHA2DS2-VASc scores could predict platelet reactivity.ResultsLow CHADS2 and CHA2DS2-VASc scores were significantly correlated with lower mean platelet ADP-induced aggregation as compared with high CHADS2 and CHA2DS2-VASc scores [45.5 U (± 16) vs. 54.8 U (±15) and 44.2 U (±16) vs. 51.0 U (±17), respectively, p = 0.01 for both].ConclusionIn ACS patients treated with clopidogrel following PCI, high CHADS2 and CHA2DS2-VASc scores correlated with HPR and lower scores correlated with OPR. Further studies are needed to evaluate our findings’ clinical implications.  相似文献   
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STUDY OBJECTIVES: To determine microbial agents causing community-acquired pneumonia (CAP) in Southeast Asia. DESIGN: A prospective study. SETTING: Three general hospitals in Thailand. PATIENTS: Two hundred forty-five adult patients fulfilling the clinical criteria of CAP from September 1998 to April 2001. INTERVENTIONS: Investigations included sputum Gram stain and culture, blood culture, pleural fluid culture (if presented), urine antigen for Legionella pneumophila and Streptococcus pneumoniae, and serology for Mycoplasma pneumoniae, Chlamydia pneumoniae, and L pneumophila. RESULTS: There were 98 outpatients and 147 hospitalized patients included in the study, and an organism was identified in 74 of 98 outpatients (75.5%) and 105 of 147 of the hospitalized patients (71.4%). C pneumoniae (36.7%), M pneumoniae (29.6%), and S pneumoniae (13.3%) were the most frequent causative pathogens found in outpatients, while S pneumoniae (22.4%) and C pneumoniae (16.3%) were the most common in hospitalized patients. There was a significantly higher incidence of C pneumoniae (36.7% vs 16.3%, respectively; p < 0.001) and M pneumoniae (29.6% vs 6.8%; p < 0.001, respectively) in the outpatients than in the hospitalized patients. The incidence of S pneumoniae, L pneumophila, and mixed infections was not different between the groups. Mixed infections were presented in 13 of 98 outpatients (13.3%) and 9 of 147 hospitalized patients (6.1%), with C pneumoniae being the most frequent coinfecting pathogen. CONCLUSIONS: The data indicate that the core organisms causing CAP in Southeast Asia are not different from those in the Western countries. The guidelines for the treatment of patients with CAP, therefore, should be the same.  相似文献   
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Summary. A cell line designated SKM-1 was newly established from leukaemic cells of a 76-year-old Japanese male patient with monoblastic leukaemia following myelodysplastic syndrome (MDS). The cells were obtained from peripheral blood of the patient when he lost multiple point mutations of ras genes with acquisition of chromosomal abnormalities during disease progression in MDS. The cells grew as a single floating cell, and have been continuously growing with the morphological characteristics of immature monoblasts by serial passages during the past 42 months with a doubling time of about 48 h. By cytochemical analysis. the cloned cells were positive for butyrate esterase, but negative for the Epstein-Barr virus associated nuclear antigen. Phenotypic analysis revealed the expression of myelomonocyte specific antigens such as CD4, CD13, CD33 and HLA-DR. Cells from the primary peripheral blood and those from SO passages of the SKM-1 cell line both possessed no activated ras genes but showed karyotype abnormalities with 46.XY, del(9)(q13;q22), der(17) t(17:?)(p13:?). The SKM-1 cells have two mutations in p53 gene and overexpress the pS3 products. This cell line may contribute to a better understanding of molecular mechanisms in the progression from MDS to myelogenous leukaemia.  相似文献   
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STUDY OBJECTIVE: To test the hypothesis that haplotypes of the interleukin (IL)-10 gene are associated with clinical outcomes, comparing critically ill patients with sepsis from pneumonia vs those with extrapulmonary sepsis. DESIGN: Genetic association study. SETTING: Medical/surgical ICUs in a tertiary-care, university-affiliated teaching hospital. PATIENTS: Of 550 white patients with sepsis, 158 had pneumonia as the principle cause of their sepsis and 392 had an extrapulmonary source of sepsis. MEASUREMENTS: Haplotypes of the IL-10 gene were defined by measurement of haplotype tag single-nucleotide polymorphisms (SNPs). Primary outcome was 28-day survival. Secondary outcomes were days alive and free of organ dysfunction. RESULTS: Three SNPs in the IL-10 gene (-592 C/A, +734 G/T, and +3367 G/A) identified four major haplotypes: CGG, AGG, CTA, and CTG. Patients with pneumonia who carried one or two copies of the CGG haplotype had greater 28-day mortality (51.4%) than patients who did not carry this haplotype (29.1%, p = 0.007). Carriers of CGG had significantly more cardiovascular dysfunction (and use of vasopressors), renal dysfunction (and requirement of dialysis), hepatic dysfunction, and hematologic dysfunction (p < 0.05 in each case). In contrast, in patients with an extrapulmonary source of infection there was no significant association of the CGG haplotype (or any measured IL-10 genotype) with 28-day mortality or organ dysfunction. CONCLUSIONS: The IL-10 haplotype - 592C/734G/3367G is associated with increased mortality and organ dysfunction in critically ill patients with pulmonary sepsis but not in similarly ill patients with extrapulmonary sepsis. Therefore, polymorphisms within the IL-10 gene may be predictors of outcome in patients with sepsis from pneumonia.  相似文献   
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The preoperative determination of thelocalization of a small insulinoma is sometimesdifficult using routine imaging techniques. We have usedthe selective arterial calcium injection (SACI) test todetermine the location of the tumor preoperatively. Thepathophysiologic basis of the SACI test is based on theresponsiveness of insulinomas to calcium injected intothe feeding artery. In this study, we demonstrated the in vitro response of the insulinoma cellsto the extracellular calcium challenge by usingprimary-cultured insulinoma cells. Human insulinomacells were obtained from three patients. MIN6 cells(normal pancreatic B cells) were used as a control;their insulin response to various stimuli resembles thatof normal B cells. The insulin secretory dynamics inresponse to extracellular calcium were observed using a perfusion system. Second, the change ofthe concentration of cytosolic free calcium([Ca2+]i) was monitored byfluorometry using fura-2/AM. When the concentration ofextracellular calcium ([Ca2+]o) was changed from 2.54 mM to 10 mM, insulinsecretion from the insulinoma cells was markedlyincreased within 6 min (10- to 18-fold at maximum), andrapidly returned to the basal level; at the same time, [Ca2+]i was immediatelyelevated and reached a peak within 1 min. In contrast,in the MIN6 cells, the insulin secretion and [Ca2+]iwere not significantly changed when[Ca2+]o was switched to 10 mM. The results of these in vitro experiments agreedwith the clinical results of the SACI test. The positiveresponse of the insulinoma to the SACI test is probablydue to the different response of insulinoma cells to the extracellular calcium challengecompared with normal B cells. The role of[Ca2+]i may be important in themechanism underlying the SACI test.  相似文献   
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