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81.
The fragmented red cell (FRC) is a useful index for diagnosing and determining the severity of thrombotic thrombocytopenic purpura (TTP), thrombotic microangiopathy (TMA) and other similar conditions, as it is found in peripheral blood in patients with these diseases. The FRC expression rate has conventionally been determined by manual methods using smear samples. However, it is difficult to attain accurate quantification by such methods as they are time consuming and prone to a great margin of error. With cases of living donor liver transplantation, the current study examined the possibility of using a multi‐parameter automated hematology analyzer, the XE‐2100 (Sysmex Corporation) for FRC quantification. While there was a notable correlation between the manual and automated measurements, the manual measurement resulted in higher values. This suggested remarkable variations in judgment by individuals. The FRC values had a significant correlation with the reticulocyte count, red blood cell distribution width (RDW), fibrin/fibrinogen degradation products (P‐FDP) and lactate dehydrogenase (LDH) among the test parameters, and this finding was consistent with the clinical progression in patients. The automated method can offer precise measurements in a short time without inter‐observer differences, meeting the requirement for standardization. The determination of FRC count (%) by the XE‐2100 that enables early diagnoses and monitoring of TTP or TMA will be useful in the clinical field.  相似文献   
82.
Measurements of serum levels of thyroxine (T4), free T4, 3,5,3'-triiodothyronine (T3), free T3, 3,3',5'-triiodothyronine (reverse T3, rT3), thyroxine-binding globulin capacity (TBGcap), chorionic gonadotrophin (hCG) and thyrotrophin (TSH) were carried out prospectively in eight women with uncomplicated pregnancies, in order to examine interrelationships between the thyroid gland and thyroid stimulating hormones during pregnancy. During pregnancy the levels of T4, free T4, T3, rT3 and TBGcap were significantly elevated, and TSH was decreased. It was noted that the elevation of T4 was maintained from the 8th to the 27th week of gestation while the level of TBGcap progressively increased. The levels of free T4 and rT3 in the first and third trimesters were significantly higher than those of age-matched, non-pregnant women. The levels of hCG showed a biphasic variation, with a peak in the 8th to 15th weeks, followed by a decline in the second trimester and a small, secondary elevation in the 32nd to 39th weeks. This later elevation was positively correlated with changes in free T4 and free T3 levels. The increase of serum T4 accompanied by an increase of free T4 in the first trimester appeared due to augmented secretion of T4, rather than being secondary to the elevated levels of TBGcap.  相似文献   
83.
Slower Conduction in the TV-IVC Isthmus. Introduction : In human type I atrial flutter, the electrophysiologic substrate is unclear. In order to determine if slow conduction is mechanistically important, we evaluated conduction velocity in the tricuspid valve-inferior vena cava (TV-IVC) isthmus, right atriai free wall, and interatrial septum in patients with and without a history of atrial flutter undergoing electrophysiologic study.
Methods and Results : Nine patients with (group 1) and nine without a history of type I atrial flutter (group 2) were studied. Conduction time (msec) in the right atrial free wall. TV-IVC isthmus (bidirectional), and interatrial septum was measured during pacing in sinus rhythm at cycle lengths of 600, 500, 400, and 300 msec from the low lateral right atrium and coronary sinus ostium. Conduction velocity (cm/sec) was calculated by dividing the distance between pacing electrodes and sensing electrodes (cm) by the conduction time (sec). Conduction velocity was slower in the TV-IVC isthmus in group 1 (range 37 ± 8 to 42 ± 8 cm/sec) versus group 2 (range 50 ± 8 to 55 ± 9 msec) at all pacing cycle lengths (P < 0.05). However, conduction velocity was not different in the right atrial free wall or interatrial septum between groups 1 and 2. Conduction velocity was also slower in the TV-IVC isthmus than in the right atrial free wall and interatrial septum in group 1 patients, at all pacing cycle lengths (P < 0.05). Atrial flutter cycle length correlated with total atrial conduction time (r ≥ 0.832, P < 0.05).
Conclusion : Slow conduction in the TV-IVC isthmus may be mechanistically important for the development of human type I atrial flutter.  相似文献   
84.
85.
Objective: This study prospectively investigated morphological changes in Amplatzer Septal Occluder (ASO) over time and the influences of these changes on the atrial and aortic walls after atrial septal defect (ASD) closure.
Methods: Between August 2005 and December 2007, 78 patients with ASD were treated with ASO devices and changes in the device shape, the device thickness, and relations of the discs to the atrial and aortic walls over time were evaluated by transesophageal echocardiography immediately and 3–12 months after deployment.
Results: The maximum unstretched ASD diameter was 16.2 ± 4.8 mm and the device diameter selected was 20.6 ± 5.5 mm. At the time of last follow-up, the device thickness decreased by 17–33%, 6 of 26 devices with a flare shape on the aortic side developed a closed shape, and the relations of the discs to the anterior atrial and aortic walls changed from touching to intermittent compression in 14 of the 78 cases. In these 14 cases, the aortic rim was significantly smaller, the number of flared device shapes on the aortic side/the number of closed shapes immediately after deployment was significantly larger, and the maximum device thickness at the middle part was significantly more decreased than those in other cases.
Conclusion: As the device becomes thinner, loses its flexibility, and often changes from a flare-to-closed shape on the aortic side over time, the edges of ASO can start to compress the atrial and aortic walls. However, erosion was not recognized in these cases.  相似文献   
86.
Subpopulations of interleukin-2 receptor (IL-2R)-positive CD4 and CD8 T cells and IL-2R+ CD20 B cells in the peripheral blood lymphocytes as well as serum concentrations of soluble IL-2R (sIL2R) were measured in children aged 1–7 years who suffered acute severe asthmatic attack. Subpopulations of CD4+ IL-2R+ cells, CD8+ IL-2R+ cells and CD20+ IL-2R+ cells in the peripheral blood lymphocytes at acute severe asthmatic attack phase were significantly higher than those at non-asthmatic attack phase (P < 0.02, P < 0.03 and P < 0.02, respectively). Subpopulations of CD20+ IL-2R+ cells in the peripheral blood lymphocytes significantly decreased 5–10 days after acute severe asthmatic attack (at recovery phase, P < 0.02) and were significantly correlated with clinical severity of asthmatic attack (P < 0.05). These results indicated that activation of both T cells and B cells was important in the pathogenesis of acute asthmatic attack in young children.  相似文献   
87.
TANAKA, H., et al. : Successful Prevention of Recurrent Ventricular Fibrillation by Intravenous Isoproterenol in a Patient with Brugada Syndrome. Intravenous administration of isoproterenol restored the ST-segment configuration to nearly normal in the right precordial leads and completely prevented spontaneous VF attacks in a patient with Brugada syndrome. The formation of a Brugada-type ECG has been attributed to the transmural dispersion of repolarization of the right ventricular epicardium and related to modulation of the autonomic nervous system. Our case may provide clues to the pathophysiological mechanism of this syndrome.  相似文献   
88.
The atrioventricular (AV) conduction system in AV discordance remains unclear, especially in cases with complex cardiac anomaly. We report a case of accessory pathway reciprocating tachycardia in atrioventricular discordance (AVD) and mitral atresia with twin AV nodes. In this case, the anterior AV node was located along the atretic mitral valve. The anterior AV node was involved in tachycardia and the posterior AV node acted as a bystander during tachycardia. The anterior AV node in AVD can be located along the atretic mitral valve, and one of twin AV nodes might act as a bystander during AV reciprocating tachycardia. (PACE 2010; 637–640)  相似文献   
89.
A 13 year old boy suffering hypertension was examined for peripheral plasma renin, angiotensin-I, angiotensin-II and aldosterone. All data were within the normal range. The Captopril test and renal scintigraphy (both with and without Captopril) also showed normal patterns. Echo-Doppler velocimetry of the renal artery revealed that left renal arterial peak flow velocity was fast (3.4 m/s). The patient was therefore diagnosed with left renal arterial stenosis. Angiography demonstrated the duplex of the left renal artery and stenosis of the left lower renal artery. Percutaneous transluminal angioplasty was successfully performed.  相似文献   
90.
Diarrheal disease is the major cause of childhood morbidity in developing countries. Although malnutrition is known as a risk factor for severe gastroenteritis, the role of enteric pathogens in the clinical severity is unclear. The present study was conducted in well nourished Ghanaian preschool children during a 3 month period of the rainy season to assess the relationship between enteric pathogens and severe gastroenteritis. Two hundred and twenty-five children with acute gastroenteritis and 64 age-matched control children were prospectively examined for the severity of dehydration and enteric pathogens in their stools. Of the 225 children with gastroenteritis, 69.8% (157/225) had mild dehydration and 30.2% (68/225) had severe dehydration. Bacteria were similarly isolated in stool samples from children with mild and severe dehydration and controls. Rotavirus accounted for 20.6% of children with severe dehydration and was more often isolated in stools from patients with severe dehydration than those from controls. Furthermore, the mixed infections associated with rotavirus and bacteria were more often found in patients with severe dehydration than those with mild dehydration or controls. Parasites were similarly found at low incidences among the three groups. The present study implied that rotavirus was more responsible for severe gastroenteritis than bacteria or parasites. However, factors other than enteric pathogens must be sought in a considerable number of severe cases. A large scale study throughout a year is recommended to obtain more precise information that would reflect the seasonal variation of rotavirus infections.  相似文献   
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