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41.
AL Warshaw RH Schapiro JT Ferrucci JJ Galdabini 《Canadian Metallurgical Quarterly》1976,70(4):562-567
Long strictures of the intrapancreatic portion of the common bile duct were found in 6 patients with chronic pancreatitis. These strictures were responsible for painless obstructive jaundice, recurrent cholangitis, secondary biliary cirrhosis, and chronic abdominal pain difficult to distinguish from that caused by pancreatitis. Endoscopic retrograde cholangiopancreatography and intraoperative cholangiography were invaluable in making the diagnosis and in planning surgical correction. Decompression of the biliary tree by anastomosis of the gallbladder or common duct to the small intestine completely relieved symptoms and allowed liver function to improve significantly. Common duct stricture as a complication of chronic pancreatitis should be considered in the differential diagnosis of extrahepatic biliary obstruction and whenever surgical treatment of chronic pancreatitis is contemplated. 相似文献
42.
On curettage, done in a 39 year old patient because of metorrhagia, a peanut-sized nodule was scraped away from the endometrium. Histologically it consisted of a jumble of irregularly shaped portions of normal appearing embryonal cartilage, of tortuous thick-walled vessels, of twisted bundles of nerves of ducts of respiratory and intestinal epithelium, and of sheets of hornifying skin. The haphazard disarray of tissues supported the notion that the lesion was not a remnant of a malformed embryo. Step-sections through the lesion revealed no traces of placental villi or decidua in the surrounding endometrium. The following were considered as possible origins of the teratoma: 1. displaced germinal cells, 2. retention of pluripotent müllerian epithelium, 3. overaged or blighted ovum. The latter seems most compatible with the histological findings. 相似文献
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Two experiments were conducted to investigate the effects of varying levels of pantothenic acid on the efficiency of energy utilization and changes in body composition of the growing chick. The results indicate that a pantothenic acid deficiency does not interfere with the chick's ability to obtain metabolizable energy from the diet. The data do show that the efficiency of energy utilization and body composition were markedly affected when chicks were fed diets deficient in pantothenic acid. In both experiments, protein, fat and energy stores were significantly reduced when pantothenic acid-deficient diets were fed. Increased estimates of heat increment per gram of diet were observed when levels of pantothenic acid below the N.R.C. (1971) recommended level of 10 mg. per kg of diet were fed. 相似文献
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BACKGROUND: Evaluation of the sustainability of iodine-deficiency disorders control programs guarantees successful and sustained virtual elimination of iodine deficiency. The Lesotho universal salt iodization legislation was enacted in 2000 as an iodine-deficiency disorders control program and has never been evaluated. OBJECTIVES: To assess the sustainability of the salt iodization program in Lesotho, 2 years after promulgation of the universal salt iodization legislation. METHODS: The proportion to population size method of sampling was used in 2002 to select 31 clusters in all ecological zones and districts of Lesotho. In each cluster, 30 women were selected to give urine and salt samples and 30 schoolchildren to give urine samples. The salt samples were analyzed by the iodometric titration method, and the ammonium persulfate method was used to analyze the urine samples. The chairperson of the iodine-deficiency disorders control program was interviewed on programmatic indicators of sustainability. SAS software was used for statistical analysis of the data. RESULTS: The urinary iodine concentrations of very few children (10.1% and 21.5%) and women (9.8% and 17.9%) were lower than 50 microg/L and 100 microg/L, respectively. At the household level, 86.9% of the households used adequately iodized salt. Only four indicators of sustainability have been attained by the salt iodization program in Lesotho. CONCLUSIONS; Iodine-deficiency disorders have been eliminated as a public health problem in Lesotho, but this elimination is not sustainable. Effective regular monitoring of salt iodine content at all levels, with special attention to iodization of coarse salt, is recommended, together with periodic evaluation of the iodization program. 相似文献
48.
H.D. Joubert H.C. Swart 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(16):2575-2578
Classical inter-diffusion studies assume a constant time of annealing when samples are annealed in a furnace. It is assumed that the sample temperature reaches the annealing temperature immediately after insertion, while the sample temperature immediately drops to room temperature after removal, the annealing time being taken as the time between insertion and removal. Using the above assumption, the diffusion coefficient can be calculated in a number of ways. In reality, the sample temperature does not immediately reach the annealing temperature; instead it rises at a rate governed by several heat transfer mechanisms, depending on the annealing procedure. For short annealing times, the sample temperature may not attain the annealing temperature, while for extended annealing times the sample temperature may reach the annealing temperature only for a fraction of the annealing time. To eliminate the effect of heat transfer mechanisms, a linear temperature ramping regime is proposed. Used in conjunction with a suitable profile reconstructing technique and a numerical solution of Fick’s second law, the inter-diffusion parameters obtained from a linear ramping of Ni/Cu thin film samples can be compared to those obtained from calculations performed with the so-called Mixing-Roughness-Information model or any other suitable method used to determine classical diffusion coefficients. 相似文献
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HP Kourea MH Bilsky DH Leung JJ Lewis JM Woodruff 《Canadian Metallurgical Quarterly》1998,82(11):2191-2203
BACKGROUND: To determine the effects of anatomic site on the presentation and diagnosis of malignant peripheral nerve sheath tumors (MPNSTs) and on the treatment and outcomes of the patients, the authors initiated a study of these tumors at different sites. An earlier report described MPNSTs of the buttock and lower extremity, and the current series analyzes those presenting at intrathoracic (IT) and subdiaphragmatic (SD) paraspinal sites. METHODS: The authors reviewed data on patients with paraspinal MPNSTs who were seen at Memorial Hospital during the period 1960-1995 and for whom histologic slides were available. Various clinicopathologic parameters and their effects on patient outcomes were examined. RESULTS: Twenty-five patients with 26 tumors were evaluated. Seven tumors were IT and 19 were SD; 60% of the patients had neurofibromatosis type 1 (NF1). Most patients presented with pain, and a diagnostic delay (of 3 months to 2 years) was often noted. Mean tumor sizes for SD and IT tumors were 14.3 cm and 6.6 cm, respectively. Most MPNSTs were composed of spindle cells in fascicles. Twenty-seven percent exhibited divergent differentiation. Twenty-four tumors were high grade, and a low grade component was identified in 8 tumors. Surgical resection was attempted for 23 tumors (88%), but complete resection was achieved in only 6 cases (23%). Eighty percent of the patients died of their tumors, 2-year and 5-year survival rates were 35% and 16%, and median survival was 8.5 months. Significant prognostic factors were tumor size <5 cm, the presence of a low grade component, and complete tumor resection. CONCLUSIONS: Paraspinal MPNSTs have more aggressive behavior than peripherally located tumors, mainly because of the difficulty encountered in resecting them completely. Prognoses of patients with MPNST at this site appear to be affected by resection status, tumor size, and tumor grade. 相似文献