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A retrospective review of 56 patients operated upon for tumours of Oddi was performed in order to determine optimal diagnostic and therapeutic procedures. Common presenting symptoms were jaundice (86%) and anemia (21%). Mean size of the tumour was 2.3 cm. Five tumours were benign and 51 were malignant. According to the classification of Martin, five were grade I: 10 grade II; 18 grade III; and 18 grade IV. Forty-seven patients underwent resection of the tumour: three local excisions for small benign tumors, six ampullectomies (followed in three by a Whipples’ procedure for recurrence) and 41 Whipples’ procedures. The hospital mortality was 5.3%, minor complications appeared in 21%. The overall five years survival was 41%. It was 75% in grade I, 50% in grade II, 40% in grade III and 10% in grade IV. The patients who received ampullectomies were alive with a follow-up of one, two and three years. All patients operated upon for a benign tumour were alive except one who died of cardiac failure. Ultrasonography and duodenoscopy are the most useful tests for the diagnosis of tumours of Oddi. Prognosis depends on the degree of infiltration of the duodenal wall and the presence of positive lymph nodes. Whipples’ procedure is best but ampullectomy can be used in elderly or poor risk patients. Malignant tumours of the ampullary region are infrequent and reported to constitute betwee 0.02 and five percent of all cancers of the digestive tract. With wider application of endoscopic techniques, there has been an increasing interest in this group of tumours during recent years. In the literature tumours of Oddi are usually reported in the group of periampullary tumours, including tumours of the ampulla itself, duodenal wall surrounding the ampulla, the distal part of the common bile duct and head of the pancreas. We have wanted to distinguish specifically the tumours of the ampulla of Vater and have adopted the term tumour of Oddi introduced by Marchal and Hureau.The sphincter of Oddi exactly delineates the junction between the bile duct, pancreatic duct and duodenum. We wanted to avoid using the anatomic term ampulla of Vater, since this structure rarely appears as an ampulla. This then excludes tumours in the head of pancreas, common bile duct above ths phincter of Oddi and tumours of the duodenal wall adjacent to the papilla. These tumours seem to behave differently from other pancreatic tumours, as they carry a different prognosis and need special attention. We have therefore reviewed retrospectively 56 patients with tumours of Oddi with special reference to diagnosis, histopathologic examination and surgical therapy.  相似文献   
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Gangliosides are glycosphingolipids found ubiquitously on thesurface of mammalian cells. They contain a ceramide tail thatis inserted into the membrane and exposed carbohydrate and sialicacid moleties. The non-toxic B subunit oligomer (EtxB) of Escherichiacoli heat-labile enterotoxin (Etx) is a potent immunogen invivo and has profound modulatory effects on EtxB-primed lymphocytesin vitro, properties which are dependent on its ability to bindto GM1 ganglioside receptors. Here, it is shown that cross-linkingGM1 by EtxB causes a differential effect on mature CD4+ andCD8+ T cells from lymph node cultures proliferating in responseto an unrelated antigen, ovalbumin. Addition of EtxB to suchcultures led to the complete depletion of CD8+ T cells comparedwith enhanced activation of CD4+ T cells [as measured by expressionof CD25 (IL-2R)]. By contrast, addition of a mutant EtxB, EtxB(G33D),which does not bind to GM1, failed to trigger CD8+ T cell depletion.When EtxB was added to isolated non-immune CD8+ lymphocytesrapid (12–18 h) alterations in nuclear morphology andthe appearance of sub-G0/G1 levels of DNA were induced; propertieswhich are characteristic of cells undergoing apoptosis. EtxB(G33D)failed to trigger apoptosis, indicating that the induction ofthe apoptotic signal was dependent on the binding of GM1. Thesefindings provide an insight into the potent immunogenicity andimmunomodulatory properties of E. coli enterotoxins as wellas heralding a novel method for the selective induction of apoptosisin mature CD8+ T lymphocytes.  相似文献   
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BACKGROUND: We proposed previously that the mean lysine requirement value is approximately 30 mg * kg(-)(1) * d(-)(1) rather than the proposed 1985 FAO/WHO/UNU estimate of the upper range of the requirement, which is 12 mg * kg(-)(1) * d(-)(1). OBJECTIVE: Our objective was to explore the 24-h pattern and rate of whole-body lysine [l-(13)C]oxidation and status of whole-body lysine balance in healthy, young adults given an L-amino acid diet supplying either a low lysine intake (14-15 mg * kg(-)(1) * d(-)(1)) or an intermediate lysine intake (29 mg * kg(-)(1) * d(-)(1)) for 6 d before a continuous tracer study with L-[1-(13)C]lysine. DESIGN: Five subjects received the low lysine intake, 6 subjects received the intermediate intake, and all were studied by using a standard 24-h oral tracer protocol that was described earlier for studies at a generous lysine intake. RESULTS: The rate of lysine oxidation was not significantly different between the 12-h fasted and 12-h fed states. The daily oxidation rate (f1.gif" BORDER="0"> +/- SD) was 27. 9 +/- 8.8 and 27.3 +/- 17.6 mg lysine * kg(-)(1) * d(-)(1) for the low- and intermediate-intake groups, respectively (NS). Daily lysine balance was -12.4 +/- 92 and 1.8 +/- 17.7 mg * kg(-)(1) * d(-)(1), respectively (P < 0.025), for the low and intermediate intakes. The balance was significantly less than zero (P < 0.001) for the low intake. CONCLUSION: The FAO/WHO/UNU lysine requirement value is not sufficient to maintain lysine homeostasis in healthy adults. From the results of this and tracer studies done by others, the mean lysine requirement of healthy adults was determined to be 30 mg * kg(-)(1) * d(-)(1).  相似文献   
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OBJECTIVE: We wanted to determine whether the standard three-view ankle radiographic series could be replaced by a two-view combination, and if so, which two-view combination (anteroposterior with lateral or mortise with lateral) would be superior. MATERIALS AND METHODS: During a 12-month period, we retrospectively reviewed 556 consecutive ankle radiographic studies consisting of anteroposterior, mortise, and lateral views. One hundred twenty patients with at least one ankle fracture were paired with 140 healthy control subjects. Each image in the three-view examination was separated and sorted by view and studied independently; all images were reviewed by two skeletal radiologists and two orthopedic surgeons. Each radiograph was evaluated for fracture of the medial, lateral, and posterior malleoli and the foot using a five-point confidence rating. Performance of each view and modeled two- and three-view combinations of views was evaluated with modified receiver operating characteristic analysis. RESULTS: The data provide little support for preferring either two-view combination (anteroposterior-lateral or mortise-lateral) for any type of fracture. The three-view combination does detect significantly more fractures than some two-view combinations in some locations, and there is a statistically significant cost in diagnostic accuracy for eliminating the anteroposterior or mortise view. CONCLUSION: Reducing the ankle radiographic series from three to two views would result in a small but significant decrease in the detection of fractures of the ankle and foot. Both two-view combinations are equivalent for fracture detection.  相似文献   
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Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age‐adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.  相似文献   
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