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71.
Todd JF  Stanley SA  Roufosse CA  Bishop AE  Khoo B  Bloom SR  Meeran K 《Lancet》2003,361(9353):228-230
Glucagon-like peptide 1 (GLP-1), an insulinotropic hormone normally synthesised in the intestinal mucosa and released in response to a meal, is essential for normal glucose homoeostasis. There is much interest in the use of GLP-1 to treat diabetes, since the risk of hypoglycaemia is thought to be low. We report an instance of a 45-year-old woman with a GLP-1 and somatostatin secreting neuroendocrine tumour who presented with reactive hypoglycaemia and hyperglycaemia, but who was subsequently cured by surgery. This case, of a neuroendocrine tumour secreting GLP-1 and causing reactive hypoglycaemia, indicates a potential adverse effect of GLP-1 therapy for diabetes.  相似文献   
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OBJECTIVE: To assess the nutritional status of female competitive figure skaters during preseason, competitive season, and off-season. SUBJECTS: Eighteen female competitive figure skaters, age range 14 to 16 years, from the New England region. STATISTICS: Data was analyzed by repeated measures analysis of variance, Duncan Multiple Range Tests, one-sample t tests, and confidence intervals. DESIGN: Nutrient intakes were determined from 3-day diet records. Body composition was assessed through heights, weights, and underwater weighing. Blood samples were drawn for analysis of selected indexes of nutritional status. RESULTS: Height and weight did not differ significantly among the seasons. Body fat was 1.1 kg higher off-season compared with preseason. Energy intake over the 3 seasons did not vary significantly (mean preseason: 1,678 kcal/day; competitive season, 1,630 kcal/day; off-season: 1,673 kcal/day) (P>.05). During the competitive season 78%, 50%, and 44% of the skaters had intakes less than 67% of RDA for folate, iron, and calcium, respectively. Most of the biochemical indexes of nutritional status were within normal limits. CONCLUSIONS: The results indicate that teenage female skaters have relatively low energy intake and inadequate intakes of certain nutrients, which may account for some of the observed seasonal variations in blood markers of nutritional status. These findings point to the need for nutrition education for these athletes, especially during their competitive season when nutritional status may be compromised.  相似文献   
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By using comparative genomic hybridization (CGH), we characterized the genetic profiles of 36 VHL-related pheochromocytomas. We then compared the results with those of sporadic and MEN 2-related pheochromocytomas. In 36 VHL-related tumors, loss of chromosome 3 and chromosome 11 were found in 34 tumors (94%) and 31 tumors (86%), respectively. There was significant concordance of deletions in chromosomes 3 and 11 (Kappa=0.64, P=0.0095), suggesting that they are involved in two different but necessary and complementary genetic pathways. The loss of chromosome 11 appeared to be specific for VHL-related pheochromocytoma as it was not present in any of the 10 VHL-related CNS hemangioblastomas studied and was significantly less common when compared with (a) sporadic pheochromocytomas from previously published results (13%; P=<0.0001), and (b) MEN 2-related pheochromocytomas from this and previously published studies (30%; P=0.0012). In summary, this is the first report of a novel consistent genetic alteration that is selected and specific for VHL-related pheochromocytoma, besides the two hits of the VHL gene.  相似文献   
74.
PURPOSE: To determine the optimal coplanar treatment technique for six-field conformal radiotherapy of prostate only (PO) or prostate plus seminal vesicles (PSV). METHODS AND MATERIALS: A series of 6-MV six-field coplanar treatment plans were created for PO and PSV volumes in 10 patients prescribed to both 64 and 74 Gy. All plans consisted of laterally-symmetric anterior oblique, lateral, and posterior oblique fields. The posterior oblique fields were varied through 20-45 degrees relative to the lateral fields, and for each of these angles, the anterior oblique fields were varied through 25-65 degrees relative to lateral. The plans were compared by means of rectal volumes irradiated to 80% or more of the prescribed dose (V80); normal tissue complication probability (NTCP) for rectum, bladder, and femoral heads; and tumor control probability (TCP). Femoral head tolerance was designated as 52 Gy to no more than 10% volume. RESULTS: For the PO group, anterior oblique fields at 50 degrees from lateral and posterior oblique fields at 25 degrees from lateral produced the lowest V80, together with femoral head doses which were appropriate for most patients (V80 = 24.4+/-5.3% [1 SD]). Compared to a commonly-used six-field (reference) plan with both anterior and posterior oblique fields at 35 degrees from lateral (V80 = 26.3+/-5.9%), this represented an improvement (p = 0.001). For the PSV group, the optimal anterior and posterior oblique fields were at 65 degrees and 30 degrees from lateral, respectively (V80 = 47.5+/-6.3%). Relative to the reference plan (V80 = 49.4+/-5.6%), this was a marginal improvement (p = 0.07). CONCLUSION: The optimized six-field plans provide increased rectal sparing at both standard and escalated doses. Moreover, the gain in TCP resulting from dose escalation can be achieved with a smaller increase in rectal NTCP using the optimized six-field plans.  相似文献   
75.
The pharmacokinetics of cibenzoline were evaluated in four young healthy volunteers who received ascending oral doses of 65, 97.5, 130, 162.5, 195, 227.5, and 260 mg separated by one week. Cibenzoline plasma concentrations exhibited an apparent biexponential decline following oral absorption. Maximum plasma concentrations and area under the plasma concentration-time curve increased in proportion to the dose. The mean elimination half-life among subjects was independent of dose and ranged from 7.3 to 8.7 hours. Oral clearance ranged from 380 to 575 ml/min and was also independent of dose. A single pharmacokinetic equation was used to adequately describe the plasma concentration data over the entire range of doses for each subject, indicating dose-proportional and linear pharmacokinetics.  相似文献   
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The nutritional factors which affect lead absorption have been studied. Synthetic diets of known composition were compounded to contain 0·075% Pb as PbCl2 labelled with 203Pb. Rats were exposed to lead for periods of 48 hr. The dietary intake was then measured and the absorption of lead determined by means of a whole-body counter. Lead absorption was increased by high fat, low mineral, low protein and high protein diets but was decreased by high mineral diet. Low fat, low fibre, high fibre, low vitamin and high vitamin diets had no effects on lead absorption.  相似文献   
80.
Rabbit tubal repair surgery was aseptic with Nembutal and ether anesthesia. Both tubes were cut at the uterotubal junction, a .61 mm thick polyethylene splint was inserted, sutured to the myometrium, and the junction sutured. At 2, 6, 10, 16, and 24 weeks the splint was removed through an incision. After a dye test for patency, 1 tube was removed and the rabbit was mated 1 week later. Results were 30% distorted placement of tube, 30% fibrose tubes (especially after 16 weeks), 47% adhesion (particularly after 6 weeks), some infection, and 55% positive dye flow test. 3 out of 7 rabbits delivered, all in those of the 2-week group that had no adhesions. 2 of the pregnancies occurred in rabbits with no dye passage.  相似文献   
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