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61.
The antigen reacting with complement-fixing antibodies in the sera of patients with primary biliary cirrhosis was localized predominantly in the mitochondrial fraction of tissue homogenates obtained by differential centrifugation. Purified mitochondrial preparations had a high content of the antigen whereas purified lysosomes failed to fix complement with PBC sera. Analysis of a number of fractionation experiments showed a high correlation between antigen content and the mitochondrial enzyme succinic dehydrogenase in all fractions. There was much poorer correlation with lysosomal and micrososomal enzyme markers. The patterns of staining obtained with a fluorescein conjugate of IgG from a PBC patient closely paralleled those obtained with a histochemical method for the demonstration of succinic dehydrogenase, further confirming the mitochondrial localization of the antigen. Staining was brightest in cells containing mitochondria with well-developed cristae. Studies on mitochondria fragmented by osmotic lysis, hexane, lysolecithin, and ultrasound suggest that the antigen is associated with the mitochondrial inner membranes.  相似文献   
62.
BACKGROUND: Hemoglobin A(1c) (HbA(1c)) has been used in controlled trials for the last 10 years but has never been evaluated in clinical practice as an effective parameter for clinical outcome. We investigated the trend for glycemic control over 11 years in one county of 350,000 citizens. METHODS: We studied 226,382 HbA(1c-DCCT-aligned) from 39,455 patients in whom routine monitoring for diabetes was initiated in 1993, 1996, or 2001. The trend in glycemic control was investigated in groups by probit plots, and in individual patients by target plots. RESULTS: From 1993 to 2001, the number of HbA(1c) measurements increased three-fold. The number of new monitoring series increased from 0.22% to 0.27% of the county population, and the number of patients monitored using HbA(1c) as a proxy for diabetes increased from 0.5% to 1.5%. A proportional reduction in high HbA(1c) concentrations of 5% was identified in the 1993 group, compared to 15% in the 1996 group, and 20% in the 2001 group. The percentage of patients with diabetic first HbA(1c) experiencing normalization increased from 8% to 30% for males and from 9% to 24% for females (1993-2001). The percentage of HbA(1c) concentrations that were not normalized decreased from 78% to 53% for males and from 83% to 59% for females (1993-2001). The median HbA(1c) at initiation of monitoring decreased from 8.7% in 1993 to 7.5% in 2001 (p < 10(-5)). The number of normal first HbA(1c) results in monitoring series increased from 7% to 17% for males and from 8% to 22% for females. Up to 10% of subjects developed diabetic concentrations during monitoring. CONCLUSION: On average, patients with diabetic first HbA(1c) concentrations (> or =6.62%) showed an improvement in glycemic control from 5% in 1993 to 20% in 2001. High concentrations were easiest to reduce. In patients with originally diabetic HbA(1c) levels, 66% on average showed improved glycemic control in the 2001 series compared to 50% in the 1993 series. An average of 6% (1993) vs. 9% (2001) with originally normal HbA(1c) levels showed an upward trend inHbA(1c) levels. Median HbA(1c) at initiation of monitoring decreased from 8.7% in 1993 to 7.5% in 2001 (p < 10(-5)). The incidence of new cases was constant.  相似文献   
63.
The concentration of glycine (Gly) was measured in gray matter (GM) and white matter (WM) in the human brain using single‐voxel localized 1H MRS at 7 T. A point‐resolved spectroscopy sequence with echo time = 150 ms was used for measuring Gly levels in various regions of the frontal and occipital lobes in 11 healthy volunteers and one subject with a glioblastoma. The point‐resolved spectroscopy spectra were analyzed with LCModel using basis functions generated from density matrix simulations that included the effects of volume localized radio‐frequency and gradient pulses. The fraction of GM and white matter within the voxels was obtained from T1‐weighted image segmentation. The metabolite concentrations within the voxels, estimated with respect to the GM + WM water concentrations, were fitted to a linear function of fractional GM content. The Gly concentrations in pure GM and white matter were estimated to be 1.1 and 0.1 mM, with 95% confidence intervals 1.0–1.2 and 0.0–0.2, respectively. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
64.
The incidence of gastric ulcer in hiatal hernia is highest in para-esophageal hernia and in chronic incarcerated hernia in older patients. Two patients with chronic incarcerated sliding hernias complicated by unrecognized gastric ulcération and perforation are described. One patient developed a subhepatic and mediastinal abscess; the other developed a gastropleural fistula. The incidence, clinical and roentgen findings, complications, and treatment of gastric ulcers in hiatal hernia are discussed.  相似文献   
65.
The Brazilian Consensus on Gastroesophageal Reflux Disease considers gastroesophageal reflux disease to be a chronic disorder related to the retrograde flow of gastroduodenal contents into the esophagus and/or adjacent organs, resulting in a variable spectrum of symptoms, with or without tissue damage. Considering the limitations of classifications currently in use, a new classification is proposed that combines three criteria-clinical, endoscopic, and pH-metric-providing a comprehensive and more complete characterization of the disease. The diagnosis begins with the presence of heartburn, acid regurgitation, and alarm manifestations (dysphagia, odynophagia, weight loss, GI bleeding, nausea and/or vomiting, and family history of cancer). Also, atypical esophageal, pulmonary, otorhinolaryngological, and oral symptoms may occur. Endoscopy is the first approach, particularly in patients over 40 yr of age and in those with alarm symptoms. Other exams are considered in particular cases, such as contrast radiological examination, scyntigraphy, manometry, and prolonged pH measurement. The clinical treatment encompasses behavioral modifications in lifestyle and pharmacological measures. Proton pump inhibitors in manufacturers' recommended doses are indicated, with doubling of the dose in more severe cases of esophagitis. The minimum time of administration is 6 wk. Patients who do not respond to medical treatment, including those with atypical manifestations, should be considered for surgical treatment. Of the complications of gastroesophageal reflux disease, Barrett's esophagus presents a potential development of adenocarcinoma; biopsies should be performed, independent of Barrett's esophagus extent or location. In this regard the designation "short Barrett's" is not important in terms of management and prognosis.  相似文献   
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Centronuclear myopathies (CNMs) are a group of clinically and genetically heterogeneous muscle disorders. To date, mutation in 7 different genes has been reported to cause CNMs but 30 % of cases still remain genetically undefined. Genetic investigations are often expensive and time consuming. Clinical and morphological clues are needed to facilitate genetic tests and to choose the best approach for genetic screening. We aimed to describe genotype–phenotype correlation in an Italian cohort of patients affected by CNMs, to define the relative frequencies of its defined genetic forms and to draw a diagnostic algorithm to address genetic investigations. We recruited patients with CNMs from all the Italian tertiary neuromuscular centers following clinical and histological criteria. All selected patients were screened for the four ‘canonical’ genes related to CNMs: MTM1, DNM2, RYR1 and BIN1. Pathogenetic mutations were found in 38 of the 54 screened patients (70 %), mostly in patients with congenital onset (25 of 30 patients, 83 %): 15 in MTM1, 6 in DNM2, 3 in RYR1 and one in TTN. Among the 13 patients with a childhood–adolescence onset, mutations were found in 6 patients (46 %), all in DNM2. In the group of the 11 patients with adult onset, mutations were identified in 7 patients (63 %), again in DNM2, confirming that variants in this gene are relatively more common in late-onset phenotypes. The present study provides the relative molecular frequency of centronuclear myopathy and of its genetically defined forms in Italy and also proposes a diagnostic algorithm to be used in clinical practice to address genetic investigations.  相似文献   
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