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51.
Genes of the renin-angiotensin-aldosterone system (RAAS) are natural candidates for sodium homeostasis and blood pressure regulation. To investigate the effect of a combination of polymorphisms of RAAS genes on renal sodium handling and blood pressure, 918 participants to the Olivetti Heart Study were genotyped for the following polymorphisms: I/D of angiotensin converting enzyme (ACE), M235T of angiotensinogen (AGT), A1166C of angiotensin II type-1 receptor (AT1R), and C-344T of aldosterone synthase (CYP11B2). The segmental renal sodium handling was evaluated by the fractional excretions of exogenous lithium (FE-Li), uric acid (FE-UA), and sodium (FE-Na). Twenty-eight carriers of triple homozygosity for M (AGT), A (AT1R), and C (CYP11B2) in the presence of the D allele of ACE (DD/ID) showed lower FE-Li (20.0%+/-5.9% versus 25.0%+/-7.5%; P=0.004; mean+/-sD), FE-UA (6.3%+/-2.0% versus 8.2%+/-2.7%; P=0.001), and FE-Na (0.96%+/-0.41% versus 1.22%+/-0.61%; P=0.004) as compared with all other allelic combinations (n=890), independently from age and body mass, suggesting an enhanced rate of proximal tubular sodium reabsorption. The carriers of the MM, AA, CC, DD/ID combination showed a substantially higher probability of being hypertensive (OR: 3.4 [(99% CI: 1.1 to 10.1]), independently of age and body mass. This relatively rare combination of allelic variants of candidate genes of the RAAS is associated with a significant alteration in proximal renal sodium handling and with higher risk of hypertension, suggesting that a combination of polymorphic variants at different candidate loci may affect phenotypic expression even in the absence of detectable effects of each variant at any single locus.  相似文献   
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The normal and abnormal aspects of the epitrochlear lymphatic station are not well known, mainly because the axillary basin is commonly regarded as the primary lymphatic target of all upper limb disorders. The purpose of this paper is to illustrate, through a review of specific cases, the normal and abnormal findings that can emerge during ultrasonographic (US) and color-Doppler US exploration of the epitrochlear region. We illustrate the normal anatomy and variations of the epitrochlear lymph nodes and highlight the functional role of this lymphatic station. Subsequently we describe the US and color-Doppler US findings. A number of different abnormalities are reviewed, including metastases (mainly from upper limb cutaneous melanomas), Hodgkin disease, and non-Hodgkin lymphoma, lymphadenitis (cat-scratch disease, foreign bodies, and IV drug abuse). Measures are suggested to avoid interpretative pitfalls and to carry out an effective differential diagnosis of elbow masses. This article represents a pictorial essay of the US and color-Doppler US features of various epitrochlear lymph node abnormalities that clinicians may not be familiar with.  相似文献   
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We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2, women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features.  相似文献   
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Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine.  相似文献   
57.
A cross sectional study assessed the bone mineral density (BMD) of 20 young adult patients who received a renal transplantation in childhood. The BMD of the lumbar spine, mainly trabecular bone, and of the total body, mainly cortical bone, were measured and expressed as an SD score. Fourteen patients (70%) had a BMD SD score of the lumbar spine below -1, of whom six patients were below -2. Fifteen patients (75%) had a BMD SD score of the total body below -1, of whom seven patients were below -2, Both trabecular and cortical bone appeared to be involved in the osteopenic process. The cumulative dose of prednisone was inversely correlated to both lumbar spine and total body BMD SD score. In a multiple regression analysis the cumulative dose of prednisone appeared to be the only factor with a significant effect on BMD SD score. Most young adult patients who had received a renal transplantation in childhood had moderate to severe osteopenia. Corticosteroid treatment played a major part in the development of osteopenia in these patients.  相似文献   
58.
Several conditions can clinically mimic renal colic. We assessed the accuracy of non-contrast-enhanced helical CT and of ultrasonography (US) in offering an alternative explanation for flank pain. In a 3-year period, 181 patients with acute flank pain underwent US and non-contrast-enhanced helical CT in a blinded sequence. Their efficacy in detecting both alternative causes of pain and additional findings unrelated to the pain was assessed in 160 cases with a confirmed diagnosis. An alternative cause was found in 23 cases (14%). US gave 4 false-negative results (1 acute appendicitis, 1 ovarian cyst torsion, 1 diverticulitis, and 1 papillary necrosis) and 2 false-positive results (1 acute pyelonephritis and 1 diverticulitis), with a 78% sensitivity and a 98% specificity for nonlithiasic causes. CT gave 5 false-negative results (1 complicated ovarian cyst, 1 pleuritis, 1 epididymitis, 1 acute pyelonephritis, and 1 papillary necrosis) and 1 false-positive (1 simple ovarian cyst described as a complicated lesion), resulting in a 74% sensitivity and a 99% specificity for diagnosing alternative causes. There were 130 additional US findings in 68 patients and 151 additional CT findings in 77 patients. A wide spectrum of findings can be identified in subjects imaged for flank pain. Non-contrast-enhanced helical CT and US have comparable accuracy in diagnosing causes other than stone disease. Electronic Publication  相似文献   
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Obesity in children may cause overt clinical disease in childhood. The complex endocrine and metabolic changes of obesity and insulin resistance in adolescents result in hyperinsulinemia, dyslipidemia, hypertension, steatohepatitis, glucose intolerance, type 2 diabetes, acanthosis nigricans and ovarian hyperandrogenemia, commonly known as polycystic ovarian syndrome (PCOS). Type 2 diabetes and PCOS in adolescents are new endocrine diseases in this age group that require unique approaches to diagnosis and treatment. The direct correlation between duration of disease and control of the disease, and subsequent long term complications of these two diseases, predict serious morbidity in young adult life for the affected adolescents. Pediatricians have an important role in the prevention, diagnosis and treatment of obesity, insulin resistance syndrome, type 2 diabetes and PCOS.  相似文献   
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