49 research outputs found
Pulse Timing Control of Multiple Signal Interconnections for Reduction of EMI
This paper presents pulse timing control method to reduce electromagnetic emission from multiple signal interconnections. Pulse timing control gives intentional skew between signals. Higher order harmonics are canceled because of the difference of the phase between the signals. Using this property, pulse timing control can reduce the EMI in wide frequency range. In this paper, we show that radiated electromagnetic field from multiple signal lines reduces its intensity to the same level of the field from one line by using pulse timing control. The result of measurement
shows that EMI from four differential transmission lines can be reduced more than 9 dB in the 200 MHz to 800 MHz frequency range
The relation between subjective symptom and circulation during orthostatic stress using a tilt table
起立負荷時における気分不良の有無と体循環,脳循環との関係について検討することを目的とし,電動チルト台を用いて起立負荷を行った.対象者は20代の自律神経疾患を有さない健常女性12名とし,起立負荷によって気分不良を示さなかった群を正常群とし,示した群を気分不良群とした.電動tilt tableを0°→ 30°→ 45°→ 60°→ 0°と変化させ,各段階を約3分ずつ保持した.その際,平均動脈血圧(MBP),心拍出量,心拍数,1回拍出量,総末梢血管抵抗,腓腹筋内側頭部のTotal Hb,中大脳動脈の平均血流速度(FV)と末梢血管抵抗(PI)を測定し,気分不良尺度を10段階評価でもって記録した.その結果,正常群は起立負荷に伴いFVは低下を示したが,MBP,PIに著変はなく,気分不良群はMBPの上昇に対してPIは減少し,FVはほぼ変化はみられなかった.一般的にめまいなどの気分不良症状は脳血流量の減少により生じるとされていたが,今回の結果では気分不良には脳血流量の増加による脳細動脈へのストレスなどが考えられた.This study aimed at considering the relation between subjective symptoms and the circulation of healthy women during orthostatic stress using a tilt table. From 12 healthy women in there twenties who don't have autonomic nervous disorders, two groups were formed: 1) a normal group which didn't feel ill during orthostatic stress, and 2) a FI group which feel ill during orthostatic stress. An electric tilt table was changed from 0°→30°→45°→60°→0°, and each stage was held for about 3 minutes. Mean artery blood pressure (MBP), cardiac output, heart rate, stroke volume, total peripheral resistance and total hemoglobin at the part of interior gastrocnemius (Total Hb), flow velocity (FV) and peripheral resistance (PI) of the middle cerebral artery (MCA) were measured. The scale of poor feeling was also recorded by10 stage evaluations. Consequently, although the normal group showed an FV fall with orthostatic stress,there were no significant changes in MBP and PI. In the FI group, PI decreased but FV didn't show muchchange with the rise of MBP. According to this result, the stress to the arteriola caused not by a fall but anincrease in the cerebral blood flows etc. seems thus to have been the source of the feeling
Stress fracture of the thoracic spine in an elite rhythmic gymnast : A case report
Spondylolysis, a defect or stress fracture of the vertebral pars interarticularis, occurs most frequently in the lower lumbar spine and occasionally in the cervical spine,but is extremely rare in the thoracic spine.We report the case of a 17 year-old girl,an elite rhythmic gymnast,who reported with early-stage thoracic spondylolysis at T10 and T11 levels. Physicians should be aware that performance of unusual athletic movements, such as those by gymnasts, may lead to spondylolysis in rare locations
Rapidly Progressive Glomerulonephritis with Delayed Appearance of Anti-Glomerular Basement Membrane Antibody Successfully Treated with Multiple Courses of Steroid Pulse Therapy
Patients with anti-glomerular basement membrane (GBM) antibody glomerulonephritis typically exhibit rapidly progressive glomerulonephritis (RPGN). The renal outcome as well as the prognosis of this disease is worse than other forms of RPGN such as those from microscopic polyangiitis. Therefore, early therapeutic intervention is essential to improve its prognosis. One month before referral to our hospital, a 54-year-old female attended another hospital because of macrohematuria. At that time, she had proteinuria and macrohematuria with normal renal function, was negative for anti-GBM antibodies, and was diagnosed with chronic glomerulonephritis. A month later when she was admitted to our hospital, she showed renal insufficiency and was positive for anti-GBM antibodies. Immediately after recognizing the anti-GBM antibody status, plasma exchange and the first course of steroid pulse therapy was started. After 5 days of therapy, renal biopsy confirmed severe crescentic glomerulonephritis in which all the observed glomeruli were involved with cellular crescents. Despite this, she survived without end-stage renal disease after three courses of steroid pulse therapy and seven sessions of plasma exchange. This favorable outcome reflects the repeated analysis of anti-GBM antibodies within a very short period and the rapid therapeutic intervention in addition to the intensive immunosuppressive therapies
Fabp7 Maps to a Quantitative Trait Locus for a Schizophrenia Endophenotype
Deficits in prepulse inhibition (PPI) are a biological marker for schizophrenia. To unravel the mechanisms that control PPI, we performed quantitative trait loci (QTL) analysis on 1,010 F2 mice derived by crossing C57BL/6 (B6) animals that show high PPI with C3H/He (C3) animals that show low PPI. We detected six major loci for PPI, six for the acoustic startle response, and four for latency to response peak, some of which were sex-dependent. A promising candidate on the Chromosome 10-QTL was Fabp7 (fatty acid binding protein 7, brain), a gene with functional links to the N-methyl-D-aspartic acid (NMDA) receptor and expression in astrocytes. Fabp7-deficient mice showed decreased PPI and a shortened startle response latency, typical of the QTL's proposed effects. A quantitative complementation test supported Fabp7 as a potential PPI-QTL gene, particularly in male mice. Disruption of Fabp7 attenuated neurogenesis in vivo. Human FABP7 showed altered expression in schizophrenic brains and genetic association with schizophrenia, which were both evident in males when samples were divided by sex. These results suggest that FABP7 plays a novel and crucial role, linking the NMDA, neurodevelopmental, and glial theories of schizophrenia pathology and the PPI endophenotype, with larger or overt effects in males. We also discuss the results from the perspective of fetal programming
Diagnosis of Myocardial Viability by Fluorodeoxyglucose Distribution at the Border Zone of a Low Uptake Region
Purpose: In cardiac 2-[F-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) examination, interpretation of myocardial viability in the low uptake region (LUR) has been difficult without additional perfusion imaging. We evaluated distribution patterns of FDG at the border zone of the LUR in the cardiac FDG-PET and established a novel parameter for diagnosing myocardial viability and for discriminating the LUR of normal variants. Materials and Methods: Cardiac FDG-PET was performed in patients with a myocardial ischemic event (n = 22) and in healthy volunteers (n = 22). Whether the myocardium was not a viable myocardium (not-VM) or an ischemic but viable myocardium (isch-VM) was defined by an echocardiogram under a low dose of dobutamine infusion as the gold standard. FDG images were displayed as gray scaled-bull’s eye mappings. FDG-plot profiles for LUR ( = true ischemic region in the patients or normal variant region in healthy subjects) were calculated. Maximal values of FDG change at the LUR border zone (a steepness index; Smax scale/pixel) were compared among not-VM, isch-VM, and normal myocardium. Results: Smax was significantly higher for n-VM compared to those with isch-VM or normal myocardium (ANOVA). A cut-off value of 0.30 in Smax demonstrated 100 % sensitivity and 83 % specificity for diagnosing n-VM and isch-VM. Smax less than 0.23 discriminated LUR in normal myocardium from the LUR in patients with both n-VM and isch-VM with a 94 % sensitivity and a 93 % specificity. Conclusion: Smax of the LUR in cardiac FDG-PET is a simple and useful parameter to diagnose n-VM and isch