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排序方式: 共有223条查询结果,搜索用时 15 毫秒
31.
Cardiac-gated magnetic resonance (MR) imaging was performed in rats to determine the effects of manganese ethylenediaminetetraphosphonate (TP). Ten normal rats received Mn-TP in a dose of 50 mumol/kg through a tail-vein injection. Spin-echo MR images were obtained before and every 10 minutes after Mn-TP injection for 1 hour. Cardiac signal intensity (SI) increased more than 70% after Mn-TP injection and remained nearly unchanged 1 hour after injection. Myocardial T1 was 517 +/- 49 msec in eight control rats and 282 +/- 61 msec (P less than .001) in six rats 81 +/- 0 minutes after injection. Nine rats underwent occlusion of the left anterior descending coronary artery prior to MR imaging. Images were obtained before and 15, 30, and 60 minutes after Mn-TP injection. In normal myocardium, SI increased up to 82% and remained elevated for 1 hour. In ischemic myocardium, SI rose 11%, leading to a marked contrast between the two tissue zones. T1 was also different in the two regions: In normal tissue, it was 206 msec +/- 54; in ischemic tissue, 338 +/- 82 (P less than .001). With T1-weighted MR imaging, Mn-TP showed a potential for delineating the jeopardized area after acute myocardial ischemia.  相似文献   
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Armstrong  PW  Fu  Y等 《岭南心血管病杂志》2001,7(6):402-402
病人资料 3 289例因急性冠脉综合征而接受溶栓治疗的患者,2274例接受t-PA治疗,1015例接受链激酶治疗。  相似文献   
38.
This paper describes rates and causes of injury deaths among community members in three districts of the United Republic of Tanzania. A population-based study was carried out in two rural districts and one urban area in Tanzania. Deaths occurring in the study areas were monitored prospectively during a period of six years. Censuses were conducted annually in the rural areas and biannually in the urban area to determine the denominator populations. Cause-specific death rates and Years of Life Lost (YLL) due to injury were calculated for the three study areas. During a 6 year period (1992-1998), 5047 deaths were recorded in Dar es Salaam, 9339 in Hai District and 11 155 in Morogoro Rural District. Among all ages, deaths due to injuries accounted for 5% of all deaths in Dar es Salaam, 8% in Hai and 5% in Morogoro. The age-standardised injury death rates among men were approximately three times higher than among women in all study areas. Transport accidents were the commonest cause of mortality in all injury-related deaths in the three project areas, except for females in Hai District, where it ranked second after intentional self-harm. We conclude that injury deaths impose a considerable burden in Tanzania. Strategies should be strengthened in the prevention and control of avoidable premature deaths due to injuries.  相似文献   
39.
Remedios  PA; Colletti  PM; Ralls  PW 《Radiology》1986,160(2):395-398
Cholescintigrams of 17 amebic liver abscesses (ALAs) in 13 patients were studied retrospectively. Rim enhancement around a photopenic defect was seen in nine (53%) of 17 abscesses. Most of the ALAs were solitary, in the right lobe, and ovoid. All were contiguous with the liver capsule. Ultrasonograms, obtained in 11 of 13 patients, showed the ALAs to be predominantly hypoechoic, with low-level echoes on high-gain settings. No sonographic finding could be identified to correlate with rim enhancement. Cholescintigraphic rim enhancement may allow early diagnosis of ALA in patients with right-upper-quadrant pain, facilitating early institution of specific therapy while definitive serologic confirmation of ALA is awaited.  相似文献   
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Kleiner  B; Filly  RA; Mack  L; Callen  PW 《Radiology》1986,161(1):27-29
To evaluate multicystic dysplastic kidney (MDK) and associated contralateral renal abnormalities in the fetal population, 27 cases detected and followed in utero were reviewed retrospectively. The sonographic assessment included estimation of amniotic fluid volume and interval growth, evaluation for non-genitourinary anomalies, and postnatal follow-up study. Contralateral renal anomalies were detected in 41% of the fetuses and included obstruction of the ureteropelvic junction, renal agenesis, renal hypoplasia, and bilateral MDK. The incidences of these malformations were compared with results of earlier studies of MDK in the pediatric and adult populations. Lethal anomalies, such as bilateral MDK and MDK associated with contralateral agenesis, are common (19% and 11%, respectively) in the fetal population; obstruction of the contralateral ureteropelvic junction, a nonlethal anomaly, was seen less commonly (7%). Perinatal death from lethal abnormalities may spuriously raise the incidence of nonlethal contralateral abnormalities in the pediatric and adult populations. Contralateral mild fetal pyelectasis, found in 15% of fetuses with MDK, was not clinically significant.  相似文献   
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