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Leptin and its association with polycystic ovary syndrome: a twin study.   总被引:2,自引:0,他引:2  
Polycystic ovary syndrome (PCOS) is a common endocrinopathy with symptoms such as obesity, insulin resistance and hyperandrogenemia. PCOS might be the result of a genetic disorder. Genetic discrepancy in the production of leptin, a product of the obesity gene, may lead to various endocrinopathies such as PCOS. The objective of this study was first, to ascertain the incidence of PCOS, using the gold standard; second, to ascertain the genetic property of leptin; and third, to evaluate the association between leptin concentration and PCOS. A total of 154 Tehran-resident female-female twins were studied. They included 48 pairs of monozygotic (MZ) and 29 pairs of dyzygotic (DZ) twins, aged 15-45 years. Clinical, ultrasound and biochemical findings were used to diagnose PCOS. The incidence of PCOS using biochemical and clinical features was 16.2%. The correlation coefficient between serum leptin levels of MZ twins was higher than that of the DZ twins. The serum level of leptin was similar between subjects with or without PCOS, irrespective of their zygosity. It was concluded that the incidence of PCOS is high among twins, and that leptin is likely to be genetically determined, although the effect of environmental factors cannot be denied. This study did not find any association between the diagnosis of PCOS and leptin level. However, the link between the two may lie with other entities such as eating disorders and/or obesity.  相似文献   
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For choosing an anaesthetic agent for a particular purpose, the different properties has been notified such as the convenience for use, safety for the fish, humans and the environment, effectiveness, physiological disturbances and its cost. Invariably, in any study with clove oil, it has been regarded as an effective and acceptable alternative to other anaesthetics. The aim of the present study was to investigate effects of two anaesthetic regimes, MS-222 and eugenol, on plasma biochemical parameters in Barbus sharpeyi. B. sharpeyi fingerlings (mean weight, 5?g?±?1; mean length, 6?cm?±?1) were exposed to MS-222 (100?ppm) and eugenol (40?ppm) for induction of anaesthesia. Blood samples were taken to verify the effects of these anaesthetics on plasma biochemical parameters may use as an indicator of stress at time 0 (designated for each tank at the time of exposure to anaesthetic agent), 0.5, 1, 2 and 24?h after exposure by caudal severance. Plasma biochemical parameters concentrations were not significantly affected in B. sharpeyi (p?<?0.05). These results were expected because the trials were conducted in short-term exposures. Ion balance appears to be altered only in long-term stressing condition. Based on the results of this study, eugenol appears to be a safe anesthetic for use in B. sharpeyi.  相似文献   
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The majority of functional MRI studies of pain processing in the brain use the blood oxygenation level‐dependent (BOLD) imaging approach. However, the BOLD signal is complex as it depends on simultaneous changes in blood flow, vascular volume and oxygen metabolism. Arterial spin labeling (ASL) perfusion imaging is another imaging approach in which the magnetically labeled arterial water is used as an endogenous tracer that allows for direct measurement of cerebral blood flow. In this study, we assessed the pain response in the brain using a pulsed‐continuous arterial spin labeling (pCASL) approach and a thermal stimulation paradigm. Using pCASL, response to noxious stimulation was detected in somatosensory cortex, anterior cingulate cortex, anterior insula, hippocampus, amygdala, thalamus and precuneus, consistent with the pain response activation patterns detected using the BOLD imaging approach. We suggest that pCASL is a reliable alternative for functional MRI pain studies in conditions in which blood flow, volume or oxygen extraction are altered or compromised. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Rapid screening of methicillin‐resistant Staphylococcus aureus (MRSA) colonization prior to hospital admittance is important to reduce nosocomial infections and health care costs. Molecular detection of mecA and S. aureus specific target genes has become widely established for this purpose. However, there are still limitations in potential for high‐throughput screening in the methods described. We have compared the time aspects and workload of four different DNA preparation platforms, resulting in an automated and simple MRSA screening method which combines two liquid handling systems and a simple lysis buffer. We have further transferred our in‐house dual real‐time PCR to a fast‐PCR protocol, reducing the time and labour spent on these samples to a minimum.  相似文献   
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Quinazoline-2,4(1H,3H)-dione is a major class of N-fused heterocyclic with a wide range of biological functions, including anti-HIV, anticancer, antifungal, antibacterial, antimutagenic, anticoccidial, anticonvulsant, anti-inflammatory, antidepressant, antimalarial, antioxidant, antileukemic, and antileishmanial activities, and other activities, has attracted high attention in organic and medicinal chemistry. As a consequence, all chemists and pharmaceutical chemists should be familiar with the various procedures for producing quinazoline-2,4(1H,3H)-dione. The main purpose of this paper is to provide an overview of the many manufacturing methods for various biological compounds based on the quinazoline-2,4(1H,3H)-dione and 2,4-dichloroquinazoline cores.  相似文献   
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ObjectiveWe conducted a systematic review and dose–response meta-analysis of prospective studies to summarize findings on the associations between intakes of soy, soy isoflavones, and soy protein and risk of mortality from all causes, cancers, and cardiovascular diseases.MethodsOnline databases were systematically searched to identify relevant articles published earlier than May 2018. We applied restricted cubic splines using random-effects analysis to assess dose–response associations. Between-study heterogeneity was assessed by I2 value and Cochrane Q test. Potential publication bias was assessed by visual inspection of funnel plots and Begg regression test.ResultsIn total, 23 prospective studies with an overall sample size of 330,826 participants were included in the current systematic review and the meta-analysis. Soy/soy products consumption was inversely associated with deaths from cancers (pooled relative risk 0.88, 95% CI 0.79 to 0.99; P=0.03; I2=47.1%, 95% CI 0.0% to 75.4%) and cardiovascular diseases (pooled effect size: 0.85, 95% CI 0.72 to 0.99; P=0.04; I2=50.0%, 95% CI 0.0% to 77.6%). Such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality. In addition, higher intake of soy was associated with decreased risk of mortality from gastric, colorectal, and lung cancers as well as ischemic cardiovascular diseases. Participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category. We also found that a 10-mg/day increase in intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and also breast cancer respectively. Furthermore, a 12% reduction in breast cancer death was indicated for each 5-g/day increase in consumption of soy protein. However, intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.ConclusionsSoy and its isoflavones may favorably influence risk of mortality. In addition, soy protein intake was associated with a decreased risk in the mortality of breast cancer. Our findings may support the current recommendations to increase intake of soy for greater longevity.  相似文献   
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