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Our aim was to find a simple method of removing labile glycosylated hemoglobin (HbA1c) from blood samples before it is measured by cation-exchange chromatography. Labile HbA1c is formed by the binding of glucose to the NH2-terminal valine of the beta-chain of HbA. We sought a more competitive binder for the same site to dissociate labile HbA1c to glucose and HbA. Inorganic phosphates were found to have a strong allosteric effect and a great ability to eliminate labile HbA1c. We developed our method with 4 mM tetrapolyphosphate in the hemolyzing solution to eliminate labile HbA1c during the automatic processing (at pH 6 and heated for 2 min at 45 degrees C) of blood samples for HbA1c estimation. This may be useful when estimating HbA1c by the manual method.  相似文献   
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Lipoprotein [a] (Lp[a]) is known to show high values in patients with ischemic heart disease (IHD). In the present study attempts were made to determine Lp[a] levels and to investigate the association of Lp[a] and other atherosclerotic risk factors in patients with chronic renal failure treated by hemodialysis. Lp[a] concentrations were measured in 30 hemodialysis patients in the age range 34 to 77 years. Mean (+/- SD) levels of serum Lp[a] were not elevated in the hemodialysis patients compared to controls (19.3 +/- 18.0 mg/dl vs. 18.3 +/- 10.4 mg/dl, respectively). We found no statistically significant correlation of Lp[a] with either cholesterol, triglycerides, HDL-C or apoproteins. However, compared with controls, more than fivefold as many of those hemodialysis patients had high risk (greater than 30 mg/dl) concentrations of Lp[a]. Lp[a] tended to increase in hemodialysis patients with diabetes mellitus and/or ischemic heart disease. In patients with high levels of Lp[a] (greater than 30 mg/dl), Lp[a] tended to correlate positively with cholesterol, LDL-, HDL-C, apo B or apo B/AI. Incidence of IHD was also elevated in these patients. Along with other known risk factors such as hyperlipidemia and hypertension, an increased concentration of Lp[a] may play an important role in accelerating development of atherosclerosis in this condition.  相似文献   
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OBJECTIVE: The baseball-diamond principle is generally used for trocar placement during video-assisted thoracic surgery; however, we are unable to treat all peripheral lung lesions using this principle. Therefore, we have developed another method for determining trocar placement based on a modification of the conventional principle. We have termed this method the triangle target principle. This report describes the instrument positioning that we now use for many video-assisted thoracic surgical procedures. METHODS: We position 3 trocars in an equilateral triangle, with the target lesion at the apex. One vertex of the base becomes the site of the first trocar placement for introduction of the thoracoscopic camera. Another vertex of the base becomes the site for the second trocar for forceps or the endoscopic stapler. The third trocar is for forceps and is inserted to create the vicinity of target lesion. Four types of the triangle target principle were developed according to sites of the target lesion. RESULTS: Between January 2000 and December 2002, we used this principle for 161 patients who underwent video-assisted thoracic surgery and all intrathoracic lesions were accessible except in 3 patients requiring intraoperative modifications. CONCLUSIONS: We conclude that video-assisted thoracic surgery by this principle is more effective and easier than the conventional principle to treat intrathoracic disease.  相似文献   
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A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented.  相似文献   
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