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排序方式: 共有2338条查询结果,搜索用时 15 毫秒
91.
Cristiano Barros de Melo Marcos Eielson Pinheiro de Sá Antonizete dos Reis Souza Anapolino Macedo de Oliveira Pedro Moacyr Pinto Coelho Mota Paulo Ricardo Campani Janaína Oliveira Luna Sérgio Cabral Pinto Fábio Fraga Schwingel Concepta McManus Luiza Seixas 《Emerging infectious diseases》2014,20(11):1933-1935
92.
Patricia Lpez‐Arellano Keila Lpez‐Arellano Jaquelinne Luna Diana Flores Javier Jimnez‐Salazar Graciela Gavia Mario Teteltitla Juan Jos Rodríguez Alejandro Domínguez Eduardo Casas Ivan Bahena Miguel Betancourt Cristina Gonzlez Yvonne Ducolomb Edmundo Bonilla 《Environmental toxicology》2019,34(1):92-98
Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acid family of compounds. Due to the presence of strong carbon–fluorine bonds, it is practically nonbiodegradable and highly persistent in the environment. PFOA has been detected in the follicular fluid of women, and positively associated with reduced fecundability and infertility. However, there are no reports concerning the experimental evaluation of PFOA on oocyte toxicity in mammals. The aim of the present study was to determine if PFOA is able to induce oxidative stress in fetal ovaries and cause apoptosis in oocytes in vitro. In addition, since inhibition of the gap junction intercellular communication (GJIC) by PFOA has been demonstrated in liver cells in vivo and in vitro, the effect of PFOA on the GJIC between the oocyte and its supportive cumulus cells was studied. Results show that PFOA induced oocyte apoptosis and necrosis in vitro (medium lethal concentration, LC50 = 112.8 μM), as evaluated with Annexin‐V‐Alexa 508 in combination with BOBO‐1 staining. Reactive oxygen species (ROS) levels, as assessed by DCFH‐DA, increased significantly in fetal ovaries exposed to ¼ LC50 (28.2 μM, a noncytotoxic and relevant occupational exposure concentration) and LC50 PFOA ex vivo. This perfluorinated compound also caused the blockage of GJIC in cumulus cells‐oocyte complexes (COCs) obtained from female mice exposed in vivo, as evaluated by calcein transfer from cumulus cells to the oocyte. The ability of PFOA of disrupting the GJIC in COCs, generating ROS in the fetal ovary and causing apoptosis and necrosis in mammal's oocytes, might account for the reported association between increasing maternal plasma concentrations of PFOA with reduced fertility in women. 相似文献
94.
Iris L Galván‐Martínez Roberto Narro‐Llorente Favio Lezama‐de‐Luna Jesus Arredondo‐Sandoval Ma. Rosy Fabian‐Victoriano Ximena Garrido‐Espindola Adriana Lozano‐Platonoff Jose Contreras‐Ruiz 《International wound journal》2014,11(6):605-610
Pressure ulcers (PU) are the source of multiple complications and even death. To our knowledge, there is no available data about PU prevalence in Mexico. The objective of this study was to determine the point prevalence of PU in three second‐level hospitals in Mexico. Every adult hospitalised patient was included in each hospital. Age, gender, hospitalisation ward, Braden score, and the number, location and stage of the ulcers encountered were recorded, as well as any pressure relief measures. In total, 294 patients were examined (127 were male); of these, 63 were considered to be at risk. The average age was 48·6 years. The overall prevalence of the PU was 17%. The service with the highest prevalence was the ICU. The most frequent stage was II (32%) and they were most commonly found in the sacrum (74%). The average Braden score of the patients with ulcers was 10, and 21·4% of the patients obtained moderate‐ to high‐risk Braden scores. Of them, 60·3% had ulcers and only 46% had any preventive measures. The prevalence of PU in three hospitals in Mexico is 17%. The most common stage is II and the most commonly affected site is the sacrum. Only 46% of patients with PU had at least one pressure release measure. 相似文献
95.
Luna Laera Giuseppe Punzi Vito Porcelli Nicola Gambacorta Lucia Trisolini Ciro L. Pierri Anna De Grassi 《Human mutation》2020,41(1):110-114
Leigh syndrome, or subacute necrotizing encephalomyelopathy, is one of the most severe pediatric disorders of the mitochondrial energy metabolism. By performing whole‐exome sequencing in a girl affected by Leigh syndrome and her parents, we identified two heterozygous missense variants (p.Tyr110Cys and p.Val569Met) in the carnitine acetyltransferase (CRAT) gene, encoding an enzyme involved in the control of mitochondrial short‐chain acyl‐CoA concentrations. Biochemical assays revealed carnitine acetyltransferase deficiency in the proband‐derived fibroblasts. Functional analyses of recombinant‐purified CRAT proteins demonstrated that both missense variants, located in the acyl‐group binding site of the enzyme, severely impair its catalytic function toward acetyl‐CoA, and the p.Val569Met variant also toward propionyl‐CoA and octanoyl‐CoA. Although a single recessive variant in CRAT has been recently associated with neurodegeneration with brain iron accumulation (NBIA), this study reports the first kinetic analysis of naturally occurring CRAT variants and demonstrates the genetic basis of carnitine acetyltransferase deficiency in a case of mitochondrial encephalopathy. 相似文献
96.
Yaoguang Zhou Luna Sun Yan Wang Lili Wu Zhuoer Sun Fan Zhang Weizhi Liu 《Clinical psychology & psychotherapy》2020,27(4):449-462
Prolonged exposure (PE) has been proved as an efficacious psychological treatment for post‐traumatic stress disorder (PTSD). There are mainly two changed formats of PE: the modified PE (mPE) and the PE combined with drug (PE/d). Symptom reduction following these two PE training formats has been reported in the patients with PTSD. However, very little is focusing on the direct comparison of mPE + PE/d and PE. Therefore, this paper aims to compare the mPE + PE/d with PE on the PTSD treatment effect and the dropout rate directly through the meta‐analysis. Eighteen studies with total sample size of 1,397 met the final inclusion criteria. The results showed that mPE + PE/d had significantly lower posttreatment PTSD severity than control group (relaxation, wait list, etc.). There was no significant difference between mPE + PE/d and PE on the posttreatment, the follow‐up PTSD score, and the posttreatment dropout rate. Compared with PE, lower PTSD symptoms and marginally lower dropout rate following the treatment were observed in the PE/d group. PE/d yielded a significantly larger effect size than mPE when compared with PE on the posttreatment PTSD symptom severity. The significance of the above results would not be changed even if studies causing high heterogeneity were removed. Although PE/d enhanced treatment effect and lowered dropout rate when compared with PE, it was still insufficient to draw the conclusion that formats of adjustments would specifically improve the implementation of PE. Further studies are warranted to develop an easily accomplished and efficacy‐guaranteeing PE programme for PTSD patients. 相似文献
97.
Jose M. Guerra MD PhD Gemma Vilahur MD Antoni Bayés de Luna MD PhD Jose Angel Cabrera MD PhD Manuel Martínez-Sellés MD PhD Guiomar Mendieta MD Adrián Baranchuk MD PhD Damián Sánchez-Quintana MD PhD 《Pacing and clinical electrophysiology : PACE》2020,43(4):427-429
We present the surface electrocardiogram of an open-chest anesthetized healthy adult swine after direct application of ice at the transversus sinus of the pericardium where the Bachmann's region is located. Gradual and transient interatrial block (IAB) in the absence of structural atrial disease is described. This new experimental model demonstrated that IAB is an independent entity from left atrial enlargement. 相似文献
98.
Full‐length genome characterization and genetic relatedness analysis of hepatitis A virus outbreak strains associated with acute liver failure among children 下载免费PDF全文
99.
100.