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61.
Hyperhomocysteinemia is an independent risk factor for coronary, peripheral and cerebrovascular diseases. Moderately elevated total homocysteine (tHcy) levels have been reported in patients with overt hypothyroidism. Plasma tHcy concentration is affected by several physiological factors and is elevated under conditions of impaired folate and cobalamin status and in renal failure. The aim of this study was to assess plasma tHcy concentrations and to evaluate the role of potential determinants of plasma tHcy levels in hypothyroid patients. Fasting plasma tHcy, serum homocysteine-related vitamins folate and vitamin B(12), serum cystatin C (CysC) and creatinine, were determined in 22 hypothyroid patients and compared with 25 healthy control subjects. Creatinine clearance (CCr) was calculated using the Cockroft-Gault formula. Plasma tHcy levels were determined by HPLC with fluorescence detection and serum CysC by automated particle enhanced immunoturbidimetry. Plasma tHcy, creatinine levels were significantly higher, and serum CysC levels, and creatinine clearance values were lower in hypothyroid patients than in control subjects. Folate levels were lower in hypothyroidic group compared to the control group. There were no differences in vitamin B(12) levels between hypothyroid and control groups. Positive correlation was noted between tHcy and creatinine levels in hypothyroid patients (r = 0.596); however, an inverse correlation was found between tHcy and folate levels (r = -0.705) in hypothyroid patients. In conclusion, tHcy was increased in hypothyroidism, and this increase was more strongly associated with changes in serum folate than in serum creatinine and CysC, suggesting an altered folate status.  相似文献   
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63.
Background The role of Kupffer cells (KCs) in nonalcoholic steatohepatitis (NASH) which is regarded as a major cause of cryptogenic cirrhosis of the liver was investigated using stereological methods and electron microscopy in the rat model. To our knowledge, there is no stereological study on the volume of liver, total number, numerical density, and nuclear height of KCs of liver in the female rat fed with a high fat diet (HFD) in the literature. Method 16 female Sprague Dawley rats were randomized into HFD and control group, with HFD and standard diet for 12 weeks, respectively. In this study, two basic research methods were used to analyze the samples. One was histopathological observation at both light and electron microscopic level. The other was stereological methods that consist of Cavalieri principle for liver volume estimation and physical disector method for estimation of numerical density and total number of KCs in the liver. Results Liver volume, both mean numerical density and total number of KCs, were statistically increased in HFD rats. Ultrastructurally, a significant decrease in the mean nuclear height of KCs in HFD rats was also found. In the control group, no abnormal change was observed, but in the HFD group, some changes such as diffuse steatosis, mononuclear cell infiltration, necrosis, fibrosis, accumulation of fat droplets and intra-cytoplasmic vacuoles, and swollen mitochondria with irregular membranes were observed in the hepatocytes. Conclusion The number and activity of KCs are increased significantly in NASH induced by HFD, and KCs might be involved in the pathogenesis of steatohepatitis as previously attributed as a major cause of cryptogenic cirrhosis of the liver.  相似文献   
64.
Van der Woude syndrome (VWS) is a rare autosomal dominant disorder that is characterized by a cleft lip and palate with congenital lip pits. This is a report of a case of VWS with sinuses in the lower lip, a cleft in the upper lip, and a supernumerary tooth in the maxilla. The main characteristics of this disorder are discussed. Dental treatment of the patient was performed, but the surgical removal of the sinus was rejected by the parents. This case report brings this condition to the attention of dentists and surgeons and emphasizes lip pits may not always be identical in appearance.  相似文献   
65.
In a retrospective cross-sectional study among 202 postmenopausal women aged 46–75 years, we aimed to investigate the relationship between body composition and bone mineral density (BMD) to determine whether fat mass or lean mass is a better determinant of BMD in Turkish postmenopausal women. Lumbar spine (L1–L4) and proximal femur BMD were measured by dual energy X-ray absorbsiometry. Body composition analysis was performed by bioelectric impedance method and fat mass, lean mass, and percent fat were measured. Both fat mass and lean mass were positively correlated with BMD at the lumbar spine and proximal femur, weight and body mass index. Lean mass was also positively correlated with height and negatively correlated with age and years since menopause (P < 0.01). The correlations of fat mass and lean mass with BMD at the lumbar spine and proximal femur remained significant after adjustment for age, years since menopause and height. When the lean mass was adjusted together with age, years since menopause and height, the significant relationship between the fat mass and BMD continued, however the significant correlation between the lean mass and BMD disappeared at all sites after adjustment for fat mass. In multiple regression analyses, fat mass was the significant determinant of all BMD sites. Our data suggest that fat mass is the significant determinant of BMD at the lumbar spine and proximal femur, and lean mass does not have an impact on BMD when fat mass was taken into account in Turkish postmenopausal women.  相似文献   
66.
Structural chromosomal aberrations have been described in various types of human leukemia. The micronucleus technique provides a measure of both chromosome breakage and chromosome loss. The present study investigated micronucleus (MN) frequency in mitogen-stimulated peripheral blood lymphocytes from 20 newly diagnosed and untreated leukemia patients: 4 with acute lymphoblastic leukemia (ALL), 10 with acute myeloid leukemia (AML), and 6 with chronic lymphocytic leukemia (CLL).The mean MN frequency for untreated patients was 3.65 ± 1.47 in ALL, 3.55 ± 1.24 in AML, 3.03 ± 1.05 in CLL. No differences in MN frequency were seen between leukemia types ALL, AML, and CLL (P = 0.503). The mean basal MN frequency for all patients, regardless of leukemia type, was 3.41 ± 1.19, which was significantly higher (P = 0.001) than that of 20 age-matched control subjects, 1.87 ± 0.75. Although no significant relationship was found between age and MN frequency in patients with leukemia (r = 0.050; P = 0.835), the MN frequency in the lymphocytes of healthy control increased regularly and significantly with age (r = 0.531; P = 0.016). These data indicate that the increased baseline MN frequency in lymphocytes of untreated patients with leukemia may reflect genomic instability or deficiency of DNA repair capacity. MN enhancement in this disease may thus be a consequence of the disease process.  相似文献   
67.
Knowledge of carotid bifurcation (CB), common carotid artery (CCA) and its branches and their recognition during diagnostic imaging are also important for vascular surgical procedures in the region, such as carotid endarterectomy or radical neck dissection, catheterization and aneurysms. The surgical anatomy of the carotid arteries was studied in 20 cadavers. Micrometric values of the CB and its relation with surrounding structures, measurements belonging to the external carotid artery (ECA) and internal carotid artery (ICA), and metric data, such as lower face including the greater horn, laryngeal prominence have been evaluated by making linear measures. The diameter of the CCA at the CB under 2 cm and CB diameter was measured as 8.1 +/- 2.24 mm and 12.79 +/- 2.87 mm, respectively. Evaluating data related to the ICA and the ECA in samples, the aspect was measured the ICA and the ECA in the CB discrimination point as 21.52 +/- 20.53 degrees . In the most location of the ECA origin according to the ICA has been determined as medial position in 35 specimens. The origin of the superior thyroid artery (STA) was found to be at the same level with the CB in 40% and below it in 25% specimens. This study has provided measured objective criteria for the arterial features of the neck region, which are crucial during surgery. The origins of the branches of the CCA act as key landmarks for adequate and appropriate placement of the cross-clamp on the carotid arteries.  相似文献   
68.
STUDY QUESTION: What is the prevalence, phenotype and metabolic features of polycystic ovary syndrome (PCOS) in the same population according to three different diagnostic criteria? SUMMARY ANSWER: The prevalence of PCOS under National Institutes of Health (NIH), Rotterdam and Androgen Excess and PCOS (AE-PCOS) Society criteria was 6.1, 19.9 and 15.3%, respectively. PCOS carried a 2-fold increased risk of metabolic syndrome regardless of the diagnostic criteria used. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: The prevalence rates of PCOS differ depending on the diagnostic criteria used to define the syndrome. The current paper gives the prevalence rates of the component and composite phenotypes of PCOS in the same population and reports similar rates of metabolic syndrome in women with PCOS under contrasting diagnostic criteria. DESIGN: In this cross-sectional study, 392 women between the ages of 18 and 45 years were analyzed. PARTICIPANTS AND SETTING: When the prevalence of PCOS according to NIH was set to 8% with a precision of 2.2% and confidence interval of 95%, the sample size required for a prevalence survey was found to be 400 subjects. The study was carried out in the General Directorate of Mineral Research and Exploration, a government-based institute, in which the largest number of female staff (n = 527) are employed within a single institute in Ankara, Turkey. The study was performed between 7 December 2009 and 30 April 2010. All female subjects between the ages of 18 and 45 years were invited to participate. Women older than 45 or younger than 18 years, post-menopausal women, women with a history of hysterectomy or bilateral oopherectomy and pregnant women were excluded. Totally, 392 of the employees were recruited for the final analyses. MAIN RESULTS AND THE ROLE OF CHANCE: The prevalence of PCOS under NIH, Rotterdam and AE-PCOS Society criteria were 6.1, 19.9 and 15.3%, respectively. While the prevalence of metabolic syndrome was 6.1% in the whole study group, within the patients diagnosed as PCOS according to NIH, Rotterdam and AE-PCOS Society criteria, it was 12.5, 10.3 and 10.0%, respectively. BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION: Even though we have included women working at a single institution with a high response rate for the participation, we cannot exclude potential selection bias due to undetermined differences between our sample and background community. We might have underestimated actual prevalence of metabolic syndrome in PCOS due to lack of oral glucose tolerance test 2 h glucose data. GENERALIZABILITY TO OTHER POPULATIONS: Current results can be generalized to Caucasian populations and may present variations in other populations according to race and ethnicity. STUDY FUNDING/COMPETING INTEREST(S): This work was, in part, sponsored by Merck Serono. TRIAL REGISTRATION NUMBER: Not applicable.  相似文献   
69.
Peutz-Jeghers syndrome (PJS) is a rare, dominantly inherited disorder characterized by gastrointestinal hamartomatous polyps, mucocutaneous hyperpigmentation, and an increased risk of cancer. We present a 16-month-old child diagnosed with PJS, who had distinguishing features compared with the previously reported cases with respect to her clinical presentation, associated malignancies, and genetic analysis. To our knowledge, this is the first report of adrenocortical carcinoma in association with PJS, as well as the first instance of associated thyroid cancer in a child with PJS. We briefly review the relevant literature and highlight the recent progress achieved in the investigation of the syndrome.  相似文献   
70.
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