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排序方式: 共有465条查询结果,搜索用时 31 毫秒
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A S Sandberg C Hasselblad K Hasselblad L Hultén 《The British journal of nutrition》1982,48(2):185-191
1. Studies on mineral absorption were carried out in ileostomy patients using the metabolic balance technique. The effect of wheat bran on the absorption of phosphorus, calcium, magnesium, zinc and iron was studied. The extent of digestion of bran phytate in the stomach and small intestine was also investigated. 2. Eight patients with well established conventional ileostomies were studied during two periods while on a constant low-fibre diet. In the second period, 16 g wheat bran/d (American Association of Cereal Chemists) was added to the diet. The amount of phytate-P, non-phytate-P, Ca, Mg, Zn and Fe was determined in the ileostomy contents and in duplicate portions of the diet. 3. Of the added bran phytate-P 24-61% was recovered in the ileostomy contents. In the bran period a significantly decreased amount of Zn was absorbed, while the apparent absorption of Fe and phytate-P increased and that of non-phytate-P, Ca and Mg remained constant. Due to the mineral content of bran, the relative absorption differed in some respects from the absolute absorption, being decreased for Zn, Mg and phytate-P but unchanged for Ca, Fe and non-phytate-P. 4. It is concluded that phytate is partly digested in the stomach and small intestine or possibly absorbed. Addition of 16 g bran/d to the diet does not seem to impair the mineral absorption from the small intestine except that of Zn. 相似文献
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Tessler DA Catanzaro A Velanovich V Havstad S Goel S 《American journal of surgery》2006,191(2):191-197
BACKGROUND: The aim of this study was to identify predictive factors for malignancy in patients undergoing surgery for suspected pancreatic cancer without a preoperative tissue diagnosis. METHODS: Patients were identified by International Classification of Diseases Ninth Revision and current procedural terminology codes, respectively, for pancreatic cancer and pancreaticoduodenectomy at a single tertiary referral center between January 1998 and May 2004. Data were collected retrospectively by chart review. Multivariate analysis of potential predictive factors was performed. RESULTS: A total of 150 patients underwent surgery for documented or suspected pancreatic malignancy; 102 did not have a preoperative tissue diagnosis of cancer. Of these, 75 had neoplastic disease at surgery. Average weight loss was greater for those with malignancy (13.5 vs. 4.8 lbs; P = .014) as was mean bilirubin (6.1 vs. 3.3 mg/dL; P = .006). In multivariate analysis, a combination of weight loss >20 lbs, bilirubin >3 mg/dL, and CA 19-9 >37 U/mL had both a specificity and positive predictive value of 100% for predicting malignancy regardless of bile duct abnormalities or mass lesions on endoscopic retrograde cholangiopancreatography or endoscopic ultrasound, respectively. The positive predictive value decreased to 89.5% when any 2 of these findings were present. The presence of a mass on CT or EUS alone had a sensitivity of 84%; however, no other single finding had a sensitivity >65%. CONCLUSIONS: In patients suspected of having a pancreatic malignancy, weight loss, hyperbilirubinemia, and increased CA 19-9 level may be predictive of a final cancer diagnosis. Surgical exploration should be considered in these patients even in the absence of a preoperative tissue diagnosis. 相似文献
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A hiatal hernia can be classified as one of four types according to the position of the gastroesophageal (GE) junction and the extent of herniated stomach. Type Ⅰ, or sliding hernias, account for up to 95% of all hiatal hernias and occur when the GE junction migrates into the posterior mediastinum through the hiatus. Type Ⅱ occurs when the fundus herniates through the hiatus alongside a normally positioned GE junction. Type Ⅲ is a combination of types Ⅰ and Ⅱ hernias with a displaced GE junction as well as stomach protruding through the hiatus. Type Ⅳ paraesophageal hernias are the rarest of the hiatal hernias. Usually, colon or small bowel is herniated within the mediastinum along with the stomach. We present a case of a paraesophageal hernia with the mid-body of the pancreas as part of the hernia contents. 相似文献
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Tyshenko MG Benidickson J Turner MC Craig L Armstrong V Harrison J Krewski D 《Journal of toxicology and environmental health. Part B, Critical reviews》2007,10(1-2):143-156
Epidemiological and toxicological studies established positive associations between environmental hazards and adverse child health outcomes, including cancer, learning disabilities, behavioral problems, developmental effects, low birth weight, and birth defects. The economic and societal costs associated with children's environmental health disorders were estimated to be substantial. The existence of knowledge gaps, lack of capacity, and the jurisdictional overlap of children's environmental health issues are some of the barriers that impede effective policy decision making. To improve children's environmental health and reduce economic and societal costs, current legislative frameworks could implement a series of amendments. The main federal, provincial, and municipal legislation used to protect children in Canada, either explicitly or implicitly, is reviewed. Recommendations for improving the existing framework for protecting and strengthening children's environmental health are proposed. 相似文献