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11.
<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
12.
Face recognition ability varies widely in the normal population and there is increasing interest in linking individual differences in perception to their neural correlates. Such brain-behavior correlations require that both the behavioral measures and the selective BOLD responses be reliable. The reliability of the location of the fusiform face area (FFA) has been demonstrated in several studies. Here, we address reliability of a different kind: reliability of the magnitude of responses to faces within this localized region. We calculated split-half reliability of face-selective responses within functionally defined posterior and anterior face-selective patches in the fusiform gyrus (FFA1/FFA2). We used data from two published studies that included both a functional localizer for face-selective regions and independent data suitable for quantifying face-selectivity. We found highly reliable face selectivity in both hemispheres that was highest in the centermost voxel(s) compared to larger regions of interest. Differences in face-selectivity between the two face patches within one hemisphere and across hemispheres were also reliable. Our results reveal considerable reliability of face-selective signals in and across FFA in adults. Given the good reliability of behavioral measures of face recognition, prior failures to find a relationship between the mean response to faces in FFA and behavioral face recognition in normal adult subjects are unlikely to be due to limitations of the measurements.  相似文献   
13.
BACKGROUND: Frontotemporal dementia (FTD) is a clinically heterogeneous condition that can be associated with clinical manifestations of an extrapyramidal disorder or motor neuron disease. A range of histologic patterns has been described in patients with FTD. The most common familial form of this condition is caused by mutations in the microtubule-associated protein tau gene (MAP tau) and is associated with neuronal or glial tau inclusions. OBJECTIVES: To determine the clinical, anatomic, and pathological features of San Francisco family A and to map the mutation responsible for disease in this family. DESIGN: A systematic clinical, neuropsychologic, neuroimaging, and chromosome segregation analysis of San Francisco family A was performed. A pathological and biochemical assessment of a family member was made. SETTING: Family study. PATIENTS: San Francisco family A, with FTD, variable extrapyramidal symptoms, and prominent motor neuron disease. Afflicted family members do not have a MAP tau coding or splice regulatory sequence mutation, and the MAP tau is genetically excluded. MAIN OUTCOME MEASURES: Comparison of clinical, neuropsychologic, neuroimaging, and linkage findings of San Francisco family A with other familial forms of FTD and amyotrophic lateral sclerosis (ALS). RESULTS: The most probable location for the mutation responsible for this condition is on chromosome arm 17q, distal to the MAP tau. All previously identified susceptibility loci for FTD and ALS are excluded. Autopsy findings from an afflicted family member show distinctive tau and alpha-synuclein inclusions. Another unique feature is that the insoluble tau protein consists predominantly of the 4R/0N isoform. CONCLUSION: The condition affecting members of San Francisco family A is clinically, pathologically, and genetically distinct from previous familial forms of FTD and ALS.  相似文献   
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15.
目的探讨高脂血症性急性胰腺炎(HAP)和非高脂血症性急性胰腺炎的特点及临床救治效果。方法回顾分析我院在2013年1月至2013年12月收治的99例急性胰腺炎的临床资料,根据患者有无高脂血症将其分为HAP组(高脂血症患者)和对照组(无高脂血症的AP患者);患者均接受标准化临床治疗,比较2组患者病情、血浆生化指标、治疗转归、住院时间与费用、复发等情况。结果 HAP组重度胰腺炎比例(13.6%)明显高于对照组(7.8%),HAP组血糖和尿酸均显著高于对照组,其中HAP组血糖平均值达到对照组的171%,而HAP组的血淀粉酶却仅为对照组的44.5%;HAP组1年内的复发率(13.6%)显著高对于照组(2.6%),P0.01差异有统计学意义。结论高血脂对急性胰腺炎的病情、表现和治疗结果均有明显影响,应引起高度重视。  相似文献   
16.
Isolated mitochondrial complex IV (cytochrome c oxidase) deficiency is an important cause of mitochondrial disease in children and adults. It is genetically heterogeneous, given that both mtDNA-encoded and nuclear-encoded gene products contribute to structural components and assembly factors. Pathogenic variants within these proteins are associated with clinical variability ranging from isolated organ involvement to multisystem disease presentations. Defects in more than 10 complex IV assembly factors have been described including a recent Lebanese founder mutation in PET100 in patients presenting with Leigh syndrome. We report the clinical and molecular investigation of a patient with a fatal, neonatal-onset isolated complex IV deficiency associated with multiorgan involvement born to consanguineous, first-cousin British Asian parents. Exome sequencing revealed a homozygous truncating variant (c.142C>T, p.(Gln48*)) in the PET100 gene that results in a complete loss of enzyme activity and assembly of the holocomplex. Our report confirms PET100 mutation as an important cause of isolated complex IV deficiency outside of the Lebanese population, extending the phenotypic spectrum associated with abnormalities within this gene.  相似文献   
17.
Achondroplasia is a rare genetic disorder resulting in short‐limb skeletal dysplasia. We present the largest European population‐based epidemiological study to date using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network. All cases of achondroplasia notified to 28 EUROCAT registries (1991–2015) were included in the study. Prevalence, birth outcomes, prenatal diagnosis, associated anomalies, and the impact of paternal and maternal age on de novo achondroplasia were presented. The study population consisted of 434 achondroplasia cases with a prevalence of 3.72 per 100,000 births (95%CIs: 3.14–4.39). There were 350 live births, 82 terminations of pregnancy after prenatal diagnosis, and two fetal deaths. The prenatal detection rate was significantly higher in recent years (71% in 2011–2015 vs. 36% in 1991–1995). Major associated congenital anomalies were present in 10% of cases. About 20% of cases were familial. After adjusting for maternal age, fathers >34 years had a significantly higher risk of having infants with de novo achondroplasia than younger fathers. Prevalence was stable over time, but regional differences were observed. All pregnancy outcomes were included in the prevalence estimate with 80.6% being live born. The study confirmed the increased risk for older fathers of having infants with de novo achondroplasia.  相似文献   
18.
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
19.
In human in-vitro fertilization (IVF), the oocytes are surrounded by cumulus and corona cells at the time of insemination so that their maturity cannot easily be evaluated. The best IVF results are obtained if the oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and mechanical treatment in order to be able to perform the injection. As a consequence, the nuclear maturity of the oocytes can be evaluated and only those that have extruded the first polar body are injected. However, metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot be recognized. The purpose of this study was to investigate the effect of different timing of cumulus- corona cell removal and injection on the outcome of ICSI. For this we allowed the oocytes to complete in-vitro cytoplasmic maturation in two different culture conditions: (i) surrounded by their cumulus and corona cells or (ii) totally denuded. We performed three different studies on sibling oocytes obtained after a standardized buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated the effect of early (1-2 h after retrieval) and late (5-6 h after retrieval) oocyte denudation and injection on the survival and fertilization of the injected oocytes and on embryo cleavage after fertilization. We found no statistically significant differences between early and late injection, indicating that after a standardized buserelin/HMG protocol the metaphase-II oocytes do not need time for further cytoplasmic maturation. Furthermore, a different timing of cumulus-corona cell removal has no effect on the outcome of ICSI, suggesting that the surrounding cells are not necessary for survival, fertilization and cleavage after ICSI.   相似文献   
20.
Objective  To study associations between maternal dietary and supplement intake of antioxidants vitamin E, retinol and congenital heart defects (CHDs).
Design  Case–control study.
Setting  Erasmus MC, University Medical Center Rotterdam, the Netherlands.
Population  Participants were 276 case mothers of a child with CHD and 324 control mothers with their children.
Methods  Food frequency questionnaires covering the intake of the previous 4 weeks were filled out at 16 months after the index pregnancy. Data were compared between cases and controls using the Mann–Whitney U test. Risk estimates for the association between CHD and dietary intake of vitamin E and retinol were estimated in a multivariable logistic regression model.
Main outcome measures  Medians (5–95th percentile) and odds ratios with 95% CI.
Results  Dietary vitamin E intake was higher in case mothers than in controls, 13.3 (8.1–20.4) and 12.6 (8.5–19.8) mg/day ( P = 0.05). CHD risk increased with rising dietary vitamin E intakes ( P -trend = 0.01). Periconception use of vitamin E supplements in addition to a high dietary vitamin E intake above 14.9 mg/day up to nine-fold increased CHD risk. Retinol intakes were not significantly different between the groups and not associated with CHD risk.
Conclusions  High maternal vitamin E by diet and supplements is associated with an increased risk of CHD offspring.  相似文献   
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