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OBJECTIVE: The workup of hypoglycemia requires frequent glucose sampling. We designed these studies to determine if the Continuous Glucose Monitoring System (CGMS) and the GlucoWatch G2 Biographer (GW2B) are sufficiently accurate to use in nondiabetic children.Study design Fifteen healthy children (aged 9-17 years, 11 boys) wore a GW2B and a CGMS during a 24-hour period, and reference serum glucose was measured hourly during the day and half-hourly overnight. RESULTS: Compared with the reference glucose, the median absolute difference in concentrations measured by the GW2B (487 pairs) was 13 mg/dL, and the difference measured by the CGMS was 17 mg/dL (668 pairs), with 30% and 42% of values using the GW2B and CGMS, respectively, deviating >20 mg/dL from the reference value. The GW2B reported values <60 mg/dL in 73% of subjects, the CGMS in 60% of subjects. In none of these episodes was serum glucose truly low. Spurious high glucose concentrations also were observed with the sensors. The mean reference glucose was lowest at 5 am (89 mg/dL) and highest at 11:30 pm (106 mg/dL) during the 24-hour period. CONCLUSIONS: Neither the CGMS nor the GW2B is accurate enough to establish population standards of the glycemic profile of healthy children and cannot be recommended in the workup of hypoglycemia in nondiabetic youth.  相似文献   
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In a population-based prospective cohort study, we found no evidence of an association between smoking behavior around the time of conception and the sex of the resulting offspring.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the association between first-trimester trisomy 21 screening markers (free human chorionic gonadotropin-beta [hCG], pregnancy-associated plasma protein A [PAPP-A], and nuchal translucency) and adverse pregnancy outcome. STUDY DESIGN: This was a cohort study of 8012 patients enrolled in a National Institute of Child Health and Human Development-sponsored study of first-trimester trisomy 21 and 18 screening. Trisomy 21 and 18 risk results and individual marker levels in unaffected pregnancies and pregnancies with adverse outcomes were evaluated. RESULTS: PAPP-A <1st percentile (OR 5.4, 95% CI 2.8-10.3) and PAPP-A <5th percentile (OR 2.7, 95% CI 1.9-3.9) and free beta-hCG <1st percentile (OR 2.7, 95% CI 1.3-5.9) were associated with increased risk of intrauterine growth restriction (IUGR) with positive predictive values of 24.1%, 14.1%, and 14.3%, respectively. PAPP-A <5th percentile (OR 2.3 95% CI 1.1-4.7) and nuchal translucency >99th percentile (OR 3.5, 95% CI 1.1-11.3) were associated with increased risk of preterm delivery before 34 weeks. Increased risk at screening for trisomy 21 and 18 identified 16 of the 29 other chromosomal abnormalities (55%). Low free beta-hCG, low PAPP-A, and increased nuchal translucency were all associated with an increased rate of fetal abnormality. CONCLUSION: Extreme values of first-trimester free beta-hCG, PAPP-A, and nuchal translucency are all associated with adverse outcomes. The especially high predictive value for IUGR of PAPP-A levels below the 1st percentile suggests that patients within this group may benefit from increased surveillance for this condition.  相似文献   
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OBJECTIVE: We sought to assess the accuracy of endometrial thickness measurement in the diagnosis of endometrial cancer in patients with obesity, diabetes, and hypertension and to evaluate whether patient characteristics influence endometrial thickness irrespective of the final diagnosis. METHODS: This was a prospective study of women not using hormone replacement therapy who presented with postmenopausal bleeding at 8 hospitals in The Netherlands. All women underwent transvaginal ultrasonography and, in the event that the endometrial thickness (double layer) was more than 4 mm, subsequent endometrial sampling. The performance of endometrial thickness measurement in the diagnosis of atypical hyperplasia and endometrial cancer was evaluated in subgroups of patients with diabetes, hypertension, and obesity by using receiver operating characteristic analysis. RESULTS: Overall, we included 594 consecutive women, of whom 62 (10%) had endometrial carcinoma and 6 (1%) had atypical hyperplasia. In these women, transvaginal ultrasonography had an area under the receiver operating characteristic curve of 0.87 (standard error [SE] 0.03). In the absence of (pre)malignancy, women with diabetes or obesity were found to have thicker endometria than women without these risk factors, whereas in women with a (pre)malignancy, this difference was not present. The area under the receiver operating characteristic curve decreased to 0.74 (SE 0.05) and 0.75 (SE 0.07) in diabetic women and obese women, respectively. The presence or absence of hypertension had no impact on the accuracy of transvaginal ultrasonography. CONCLUSION: In view of the decreased diagnostic accuracy in diabetic women and obese women, the clinical value of transvaginal endometrial thickness measurement in these women is questionable.  相似文献   
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OBJECTIVE: To determine the antitumor activity and toxicity profile of gemcitabine as second-line chemotherapy in patients with recurrent or persistent uterine leiomyosarcoma (LMS). METHODS: Intravenous gemcitabine was administered over 30 min at a dose of 1000 mg/m(2) on days 1, 8, 15, with cycles repeated every 28 days. Eligibility criteria included measurable disease, performance status 0-2, adequate bone marrow function, creatinine <1.5 mg%, bilirubin <1.5x institutional normal, SGOT/alkaline phosphatase <3x institutional normal, and signed informed consent. Standard Gynecologic Oncology Group (GOG) toxicity and response criteria were utilized. RESULTS: Forty-eight patients were enrolled on the study. Three were deemed ineligible upon central pathology review, another received an inadequate course of protocol treatment, and two others were not reassessed for response; thus 44 patients were evaluable for toxicity and 42 for toxicity and response. The median age was 52.5 (range: 31-82) years. Thirty-five patients had received prior chemotherapy and 11 had undergone prior radiotherapy. Sites of measurable disease were pelvic (n = 9) and extrapelvic (n = 35). A median of two (range: 1-13) cycles was received. The schedule was well tolerated; there were no treatment-related deaths. The only grade 4 toxicities included neutropenia (n = 7), nausea and vomiting (n = 2), and dermatologic (n = 1). One (2.3%) patient achieved a complete response and eight (18.2%) experienced a partial response, for an overall response rate of 20.5%. CONCLUSION: Gemcitabine demonstrates activity in patients with persistent or recurrent uterine LMS and should be considered in multiagent regimens treating this patient population.  相似文献   
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