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11.
Hongbin Xu Nongnuj Tanphaichitr Poh-Gek Forkert Araya Anupriwan Wattana Weerachatyanukul Renaud Vincent Arthur Leader Michael G Wade 《Toxicological sciences》2004,82(2):590-597
Trichloroethylene (TCE) is a prevalent occupational and environmental contaminant that has been reported to cause a variety of toxic effects. Here, we have undertaken studies to test the hypothesis that TCE exposure adversely affects sperm function and fertilization. Sperm retrieved from mice exposed to TCE (1000 ppm) by inhalation for 1 to 6 weeks were incubated in vitro with eggs isolated from superovulated female mice. The number of sperm bound per egg was significantly decreased when mice were exposed to TCE for 2 and 6 weeks but not at exposures of 1 and 4 weeks. In vivo fertilization was also determined in superovulated female mice mated with males exposed to TCE for 2 to 6 weeks. The percentages of eggs fertilized, as assessed by the presence of two pronuclei, were significantly decreased after 2 and 6 weeks of TCE exposure. A slight but insignificant decrease was observed after 4 weeks of TCE exposure. The direct effects of TCE and its metabolites, chloral hydrate (CH) and trichloroethanol (TCOH), on in vitro sperm-egg binding were also investigated. Sperm-egg binding was significantly decreased when sperm were pretreated with CH (0.1-10 microg/mL). Significantly lower levels of sperm-egg binding were also detected with TCOH (0.1-10 microg/mL), although the decreases were not as pronounced as those for CH. These results showed that TCE exposure leads to impairment of sperm fertilizing ability, which may be attributed to TCE metabolites, CH, and TCOH. 相似文献
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Muna Sabah Robert Cummins Mary Leader Elaine Kay 《Applied immunohistochemistry & molecular morphology》2006,14(1):97-102
The p16 is a tumor suppressor gene on the short arm of chromosome 9p21. The product of the p16 acts as a negative cell cycle regulator by inhibiting G1 cyclin-dependent kinases that phosphorylate the retinoblastoma protein. This study was designed to assess the frequency of genetic loss of 9p21 and to determine the role of p16 the pathogenesis of sporadic and neurofibromatosis 1 (NF1)-associated malignant peripheral nerve sheath tumors (MPNSTs). The authors examined 15 cases for p16 protein expression and 10 cases for allelic imbalance (AI)/loss of heterozygosity (LOH) of chromosome 9p. DNA was microdissected from normal and neoplastic tissues. AI/LOH analysis was performed using six microsatellite markers on the 9p region. On immunohistochemical analysis 80% of cases showed abnormal expression of p16. Similarly, 8 of 10 cases revealed genetic loss with at least one microsatellite marker. The most frequent deletion was that within the coding sequence. Of p16 at me D9S974 locus. These findings emphasize the role of loss of p16 in the development of both sporadic and NF1-associated MPNSTs. 相似文献
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Stimulus over-selectivity describes a phenomenon where only a subset of the relevant stimuli present in the environment, control an individual’s behavior. The current experiment explored the degree to which over-selectivity increases in old age. The level of over-selectivity in a visual discrimination task in 60 individuals aged 60–89 years was assessed, as well as the degree to which this reflected attentional control. In addition, the intellectual functioning and cognitive flexibility of the participants were assessed. Results showed that, as age increased, three effects were revealed: levels of stimulus over-selectivity increased, IQ scores decreased, and cognitive flexibility decreased. However, over-selectivity was not related to IQ or cognitive flexibility, and appeared related most to attentional impairments. Thus, ageing is related to significant declines in effective stimulus control. These effects can have a serious impact on the physical and psychological health of old adults, as well as their quality of life, and, therefore, this area of research warrants further exploration. The results are discussed in relation to the attention-deficit and comparator theory of over-selectivity. 相似文献
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Idiopathic cholangiopathy in a biliary cast syndrome necessitating liver transplantation following head trauma 总被引:1,自引:0,他引:1
Byrne MF Chong HI O'Donovan D Sheehan KM Leader MB Kay E McCormick PA Broe P Murray FE McCormack A 《European journal of gastroenterology & hepatology》2003,15(4):415-417
The development of total biliary casts is very unusual, especially in patients who have not undergone liver transplantation. The aetiology of these casts is uncertain but several factors are believed to play a role, including periods of fasting, haemolysis, cholangitis and recent surgery. Resultant bile stasis and/or gallbladder hypocontractility promote sludge and subsequent stone formation. Here we present the case of a previously well 66-year-old woman who developed a total biliary cast several weeks after being involved in a road traffic accident during which she sustained head injuries but no obvious liver insult. This cast was removed at laparotomy but the patient had resultant diffuse biliary tree abnormalities and persistent cholestasis and subsequently required a liver transplant. The possible aetiologies of biliary cast formation and subsequently cholangiopathy necessitating transplantation in this patient are described. 相似文献
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Livneh Nir Braeken Dionne Drozdinsky Genady Gafter-Gvili Anat Seelig Jaap Rozovski Uri Berger Tamar Raanani Pia Falanga Anna ten Cate Hugo Spectre Galia Leader Avi 《Journal of thrombosis and thrombolysis》2021,52(2):590-596
Journal of Thrombosis and Thrombolysis - Managing anticoagulation in hematological malignancy patients with atrial fibrillation and thrombocytopenia is a clinical challenge with limited data. We... 相似文献
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Analysis of exercise-induced R wave amplitude changes in detection of coronary artery disease in asymptomatic men with left bundle branch block 总被引:1,自引:0,他引:1
Gregory S. Uhl USAF MC Major J.Andrew C. Hopkirk MRCP RAF Squadron Leader 《The American journal of cardiology》1979,44(7):1247-1250
The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block. 相似文献
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Mannion, Leader, and Healy (2013) examined the frequency of comorbid disorders in children and adolescents with autism spectrum disorder and the predictors of sleep problems. This study will extend this research by investigating the predictors of comorbidity in 89 participants. Age, gender, level of intellectual disability, presence of epilepsy, attention deficit/hyperactivity disorder (AD/HD) and an anxiety disorder were determined using a self-constructed demographic questionnaire. The Autism Spectrum Disorder-Comorbid for Children (ASD-CC) was administered to informants to assess symptoms of comorbid psychopathology. The Children's Sleep Habits Questionnaire (CSHQ) and Gastrointestinal symptom inventory were administered to assess sleep problems and gastrointestinal symptoms respectively. Sleep problems predicted gastrointestinal symptoms. Level of intellectual disability predicted gastrointestinal symptoms. Specifically, those with no intellectual disability were more likely to present with gastrointestinal symptoms. Gastrointestinal symptoms in turn predicted total comorbid psychopathology score and the individual subscales of worry/depressed, avoidant behavior, conduct behavior and tantrum behavior on the ASD-CC. Gender and ASD-CC total score predicted an individual having an anxiety disorder. Specifically, being male predicted an anxiety disorder. The ASD-CC subscales of worry/depressed and avoidant behavior predicted an anxiety disorder. The implications of these findings are discussed in the study. 相似文献