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991.
The purpose of this study was to examine relationships between aerobic fitness and birthweight in adolescents. A representative cohort of 1015 males and females aged 12 and 15 y was studied, at baseline, with 89% of the 12-y-olds being re-examined 3 y later.The main outcome measures were an index of aerobic fitness, measured in laps completed at voluntary exhaustion by a twenty-metre shuttle run test, and recorded birthweight. Multiple linear regression, with and without adjustment for known and potential confounding variables, was performed to examine associations between fitness and birthweight.Birthweight and aerobic fitness were positively related so that for each kg decrease in birthweight, there was a mean (95% confidence interval) decrease in fitness score of 4.84 (0.35 to 9.33) laps and 3.21 (0.32 to 6.10) laps, in 12-y-old boys and girls respectively. This relationship is of a similar order to the strength of association between birthweight and adult blood pressure previously reported. Associations between birthweight and physical fitness at the age of 15 were weaker and were not significant.Our findings suggest that aerobic fitness may be involved in mediating the association between birthweight and cardiovascular disease risk later in life. The weakening of the association between birthweight and fitness between the ages of 12 and 15 y is similar to the weaker associations between birthweight and blood pressure seen among adolescents compared to younger children. We are currently re-examining this cohort to see if, as with blood pressure, the association with fitness re-emerges at an older age.  相似文献   
992.
Rett syndrome results from mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene, which are nearly always lethal in males and lead to regression and reduced life expectancy in females. Herein we report one propositus with five tandem deletions and a second propositus with three tandem deletions within MECP2 exon 4 that encode truncated protein products resulting in classic Rett syndrome. These deletion breakpoints and single deletions in 3 other patients were all found within a 185-bp region along with 64 of 69 other reported deletion breakpoints in the MECP2 gene. Illegitimate recombination resulting in deletion at a substantial proportion of the shared MECP2 sites is enhanced by repeated guanosine (G) DNA sequences in the antisense direction, consistent with reports at other gene loci that polypurine (multiple guanosine or adenosine (A)) basepairs enhance sequence deletion. Multiple deletions at the same poly G recombination sites confirm the existence of deletion hotspots in this gene region with numerous repeated antisense sites that are enriched 26- to 161-fold. Deletion by illegitimate recombination within a single allele can occur during mitotic or meiotic cell cycles. Although prone to disease-causing deletion, this region is unique in humans and highly conserved among mammals for the last 75 000 000 years to maintain the MECP2 gene's critical function.  相似文献   
993.
994.

Background  

Invasion and metastasis is a complex process governed by the interaction of genetically altered tumor cells and the immunological and inflammatory host reponse. Specific T-cells directed against tumor cells and the nonspecific inflammatory reaction due to tissue damage, cooperate against invasive tumor cells in order to prevent recurrences. Data concerning involvement of individual cell types are readily available but little is known about the coordinate interactions between both forms of immune response.  相似文献   
995.
996.
Cytomegalovirus (CMV) infection is associated with adverse clinical outcomes in immunosuppressed persons. The incidence and association of CMV reactivation with adverse clinical outcomes in critically ill persons lacking evidence of immunosuppression at ICU admission has received great attention in the practice of critical care medicine. Critically ill patients in ICU who had associated risk factors such as mechanical ventilation, severe sepsis, or blood transfusion are more prone to CMV activation, which in turn led to increased mortality and morbidity in terms of increased ICU stay, longer duration of mechanical ventilation, and higher rates of nosocomial infections. However, severe CMV as initial presentation mimicking dengue infection is rare. We recently came across seven cases with positive CMV serology at ICU admission, which we discuss in the light of current literature.  相似文献   
997.
Objectives: We performed serial Doppler echocardiography in patients with ST‐elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) to describe the temporal changes in Doppler parameters following STEMI. Background: Data on comprehensive Doppler assessment of diastolic dysfunction following STEMI, incorporating tissue Doppler imaging (TDI), are lacking. Severe diastolic dysfunction in stable patients usually manifests as a restrictive mitral filling pattern (RFP), reduced TDI‐derived annular velocities (E'), and elevated E/E' ratios >15. Methods: Twenty‐eight patients (19 males, mean age 60 ± 10 years) with a first‐ever STEMI who underwent PCI were prospectively assessed with echocardiography and invasive left ventricular end‐diastolic pressure (LVEDP) measurements prior to PCI. Repeat echocardiograms were performed at day 3 and 12 months. Results: During STEMI: (i) LVEDP was significantly elevated but decreased post revascularization (26.1 ± 6.2 vs. 20.8 ± 5.2 mmHg, P = 0.002); (ii) the predominant mitral inflow pattern was an abnormal relaxation pattern (n = 14 [50%]), whereas restrictive filling pattern was only observed in seven (25%) patients; (iii) E' velocities were only modestly reduced (septal E' 7.4 ± 2.2 cm/sec, lateral E' 9.6 ± 2.2 cm/sec), and (iv) a septal E/E'ratio >15 seen in only one patient, whereas all other patients had an E/E' ratio of 8–15. Serial TDI showed that E'velocity decreased at day 3 (septal E' 7.4 ± 2.1 cm/sec vs. 5.9 ± 1.6 cm/sec, P = 0.002) and remained reduced at 1 year follow‐up, suggesting persistence of diastolic dysfunction. Conclusions: During STEMI, contrary to findings in stable patients, the predominant Doppler manifestation of the severe diastolic dysfunction and elevated LVEDP was an abnormal relaxation mitral inflow pattern accompanied by E/E' ratios of 8–15. Serial Doppler assessment suggests incomplete diastolic recovery following STEMI.  相似文献   
998.
背景和目的:COPD合并阻塞性睡眠呼吸暂停(OSA)的患者,较单独患有其中1种疾病的患者更容易罹患肺动脉高压.本研究旨在评价COPD合并OSA患者的病死率及因COPD急性加重而首次住院的关系,以及持续气道正压通气(CPAP)对患者主要临床结局的影响.  相似文献   
999.
Subacute sclerosing panencephalitis (SSPE), a post‐measles progressive neurological disorder is still common in India because of indifferent vaccination compliance. However, the acute fulminant form of SSPE is extremely rare. An unusual case of fulminant SSPE in an 18‐year‐old man from south India with an ultra‐short course of 19 days presenting with hemiparesis in absence of myoclonus and progressive cognitive decline, is reported. MRI showed frontal and parieto‐occipital demyelination extending to nuclear areas. Antimeasles antibodies were demonstrable in CSF and serum with oligoclonal bands in CSF despite normal CSF protein and cell count. At autopsy, unlike classical SSPE, oligodendroglia containing measles viral antigen was sparse despite florid necrotizing leukoencephalitis with acute demyelination. Measles virus was isolated from the brain with hypermutation in M gene confirming the diagnosis. Phylogenetic analysis of the viral genotype indicated that it belonged to D7 genotype which is considered rare in India.  相似文献   
1000.
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