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61.
In order to identify ECG characteristics of overt midseptal accessory pathways (APs) predictive of close proximity to the AV conduction system we analyzed data from patients who underwent successful RF catheter ablation of a mid-septal AP, Mean patient age was 31 ± 16 years, and 13 were male. The 40° right anterior oblique view was used to divide the mid-septal area into 3 zones: 1 (anteriorportion); 2 (intermediate); and 3 (posterior portion). The 12-lead ECG was analyzed with regard to delta wave polarity and R/S transition in the precordial leads. The findings from patients ablated at zone 3 were compared to those at zones 1 and 2. All patients had a positive delta wave in the leads I, II, aVL, and negative delta wave in the leads III and aVR. The R/S transition occurred in lead V2 in 80% of patients. The delta wave in lead aVF was the only ECG characteristic that correlated with the AP ablation zone. Six of 8 patients ablated at zone 3 had a negative delta wave in lead aVF while 6 out of 7 patients ablated at zone 1 or 2 had a positive or isoelectric delta wave in lead aVF (P = 0.03). A positive or isoelectric delta wave in lead aVF identifies mid-septal AP in close proximity to the AV conduction system.  相似文献   
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A 59-year old Cuban male had seven episodes of gastrointestinal bleeding. Angiographic and radiographic studies revealed a polypoid mass in the second portion of the duodenum. The mass proved to be paraganglioneuroma.
A review of the literature reveals only 25 previously recorded such cases. Eighty-eight per cent of the lesions were located in the second part of the duodenum; 84% of the patients were symptomatic. The two main symptoms noted were abdominal discomfort (45.5%) and bleeding (47.6%), None of the lesions was a malignant or functional tumor.  相似文献   
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The prevalence of obesity is rising at a very alarming rate in the United States. Estimates are that 27% of American adults are now considered obese, and another 52% are overweight. These individuals are at increased risk of premature mortality and the development of many comorbid illnesses. Numerous factors contribute to this epidemic. The medical treatment of obesity is difficult, but can be successful. Drug therapy and obesity surgery can be effective but more research is needed to improve all of the obesity treatments.  相似文献   
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A 73-year-old white woman was admitted to our hospital for evaluation of a chronic dermatitis. Personal history was remarkable only for arterial hypertension and noninsulin-dependent6 diabetes mellitus. Clinical and histopathologic findings were consistent with a diagnosis of mycosis fundoides (mf and staging procedures including bolld cell counts, serum biochemistry, urinalysis, bone marrow biopsy, Sé zary cell counts in peripheral bolld, computerized tomography (ct scans, abdominal ultrasonography, chest roentgenograms, serum protein electrophoresis, and immunoelectrophoresis disclosed normal or negative results (T2 N0 M0 B0). After 2 years of standard treatment, the patient's condition had progressively worsened and she presented generalized erythematious plaques and a few, small, red-bluish tumors (Fig. 1). A biopsy specimen of a tumor showed an intense lymphoid infiltrate composed mainly of large and medium-sized cells, many of which exhibited clear interacytoplasmic vacuoles (Fig. 2). These vacuoles were negative for periodic acid-Schiff, alcian blue, and oil-red-O staining. Most of the neoplastic cells stained with uchl1 antibody, and none expressed B-cell markers. Some of the malignant cells reacted wih the Ber-h2 and mb3 monoclonal antibodies. No evidence of immunoglobulin libht chain production was observed. Negative staining with cd68 monoclonal antibody ruled out a monocyte-macrophage lineage of the malignant cells. On physical examination, no palpable lymph nodes were found. The quantitative immunoglobulin study showed an IgG level of 6,950 mg/dL (noral values, 800–1,800 mg/dL), IgA level of 126 mg/dL (normal, 90–450 mg/dL), IgM level of 130 mg/dk (normal, 70–280 gm/dL).Serum immunoelectrophoresis showed an IgG lambda monoclonal protein. Further studies including blood cell count, serum biochemistry, urinalysis, bone marrow biopsy, peripheral blood Sézary cell counts, Bence-Jones proteinuria, ct scans, abdominal ultrasonography, and chest roentgenograms yielded negaive or normal results. Thus, diagnosis of monoclonal gammopathy of unknown significance (mgus ) was made. Despite treatment with systemic chemotherapy, the diesease followed an aggressive course and the patient died from Staphylococcus epidermidis septicemia.  相似文献   
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Cortical cerebellar basket cells are stable postmitotic cells; hence, they are liable to endure age‐related changes. Since the cerebellum is a vital organ for the postural control, equilibrium and motor coordination, we aimed to determine the quantitative morphological changes in those interneurons with the ageing process, using unbiased techniques. Material from the cerebellar cortex (Crus I and Crus II) was collected from female rats aged 2, 6, 9, 12, 15, 18, 21 and 24 mo (5 animals per each age group), fixed by intracardiac perfusion, and processed for transmission electron microscopy, using conventional techniques. Serial semithin sections were obtained (5 blocks from each rat), enabling the determination of the number‐weighted mean nuclear volume (by the nucleator method). On ultrathin sections, 25 cell profiles from each animal were photographed. The volume density of the nucleus, ground substance, mitochondria, Golgi apparatus (Golgi) and dense bodies (DB), and the mean surface density of the rough endoplasmic reticulum (RER) were determined, by point counting, using a morphometric grid. The mean total volumes of the soma and organelles and the mean total surface area of the RER [s?N (RER)] were then calculated. The results were analysed with 1‐way ANOVA; posthoc pairwise comparisons of group means were performed using the Newman‐Keuls test. The relation between age and each of the parameters was studied by regression analysis. Significant age‐related changes were observed for the mean volumes of the soma, ground substance, Golgi, DB, and s?N (RER). Positive linear trends were found for the mean volumes of the ground substance, Golgi, and DB; a negative linear trend was found for the s?N (RER). These results indicate that rat cerebellar basket cells endure important age‐related changes. The significant decrease in the s?N (RER) may be responsible for a reduction in the rate of protein synthesis. Additionally, it may be implicated in a cascade of events leading to cell damage due to the excitotoxic activity of glutamate, which could interfere in the functioning of the complex cerebellar neuronal network.  相似文献   
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An extremely rare congenital abnormality is reported in which the anterior descending coronary artery (LAD) originates from the pulmonary trunk. The clinical presentation, angiographic findings, and surgical treatment are discussed. This is the only reported case where surgical treatment included ligation of the LAD with internal mammary artery bypass grafting.  相似文献   
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