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991.
992.
B. Su T. Watanabe M. Shimizu M. Yanagisawa 《Archives of disease in childhood. Fetal and neonatal edition》1997,77(1):F36-F40
AIMS—To identify the patent ductus arteriosus (PDA) shunt flow pattern using Doppler echocardiography; and to assess whether it could be used to predict the development of clinically significant PDA.
METHODS—Premature infants weighing under 1500 g, who required mechanical ventilation, and in whom daily echocardiography could be performed from day 1 until the ductus closed, and on day 7 to confirm closure, were studied. The PDA shunt flow was identified from four Doppler patterns, and the closed pattern of a closed duct was also presented. Clinically significant PDA was diagnosed when there was colour Doppler echocardiographic evidence of left to right ductal shunt associated with at least two of the following clinical signs: heart murmur (systolic or continuous); persistent tachycardia (heart rate>160/min); hyperactive precordial pulsation; bounding pulses; and radiographic evidence of cardiomegaly or pulmonary congestion.
RESULTS—Of 68 infants enrolled into this study, clincally significant PDA developed in 31. The most recordable sequence of transition change of shunt flow pattern for clinically significant PDA was: pulmonary hypertension pattern, to growing pattern, to pulsatile pattern, to closing pattern, to closed pattern. And that for non-clinically significant PDA was: pulmonary hypertension pattern, to closing pattern, to closed pattern. The growing and the pulsatile patterns were mostly documented in infants with clinically significant PDA. The first documented growing pattern to predict clinically significant PDA gave a sensitivity of 64.5% and a specificity of 81.1%; the first documented pulsatile pattern gave a sensitivity of 93.5% and a specificity of 100%.
CONCLUSION—Doppler echocardiographic assessment of PDA shunt flow pattern during the first 4 days of life is useful for predicting the development of clinically significant PDA in premature infants. At that stage, the closing or closed Doppler pattern indicates that infants are not at risk of developing clinically significant PDA; the growing or pulsatile Doppler pattern indicates a continuing risk of developing clinically significant PDA.
相似文献
METHODS—Premature infants weighing under 1500 g, who required mechanical ventilation, and in whom daily echocardiography could be performed from day 1 until the ductus closed, and on day 7 to confirm closure, were studied. The PDA shunt flow was identified from four Doppler patterns, and the closed pattern of a closed duct was also presented. Clinically significant PDA was diagnosed when there was colour Doppler echocardiographic evidence of left to right ductal shunt associated with at least two of the following clinical signs: heart murmur (systolic or continuous); persistent tachycardia (heart rate>160/min); hyperactive precordial pulsation; bounding pulses; and radiographic evidence of cardiomegaly or pulmonary congestion.
RESULTS—Of 68 infants enrolled into this study, clincally significant PDA developed in 31. The most recordable sequence of transition change of shunt flow pattern for clinically significant PDA was: pulmonary hypertension pattern, to growing pattern, to pulsatile pattern, to closing pattern, to closed pattern. And that for non-clinically significant PDA was: pulmonary hypertension pattern, to closing pattern, to closed pattern. The growing and the pulsatile patterns were mostly documented in infants with clinically significant PDA. The first documented growing pattern to predict clinically significant PDA gave a sensitivity of 64.5% and a specificity of 81.1%; the first documented pulsatile pattern gave a sensitivity of 93.5% and a specificity of 100%.
CONCLUSION—Doppler echocardiographic assessment of PDA shunt flow pattern during the first 4 days of life is useful for predicting the development of clinically significant PDA in premature infants. At that stage, the closing or closed Doppler pattern indicates that infants are not at risk of developing clinically significant PDA; the growing or pulsatile Doppler pattern indicates a continuing risk of developing clinically significant PDA.
相似文献
993.
Several epidemiological studies have shown that the prevalence of ischemic heart disease is higher in occupational drivers than in people with other occupations. Although occupation categories can be surrogate measures for coronary risk factors, the relationships between taxi driving and severity of coronary heart disease (CHD) has not been investigated. Even more important, the contribution of risk factors to the severity of CHD in taxi drivers remains unclear. Our study tested the hypothesis that taxi driving could be associated with the severity of CHD. We also examined the relation between this occupation and risk factors and social lifestyle. We analyzed the coronary angiograms of 57 consecutive male taxi driver patients and compared them with those of 215 age-adjusted male non-taxi-driver patients. The number of diseased vessels and risk factors were compared between two groups. The prevalence of myocardial infarction and multi-vessel disease was higher in the taxi-driver patients than in the non-taxi-driver patients. The taxi-driver patients had higher prevalence of body mass index (BMI), diabetes, and smoking, higher levels of low-density lipoprotein cholesterol (LDL-C), and lower levels of apolipoprotein AI (ApoAI). Multiple logistic regression analysis showed that multi-vessel disease was associated with BMI and diabetes mellitus in taxi-driver patients. The taxi-driver patients were characterized by more extensive coronary atherosclerosis associated with higher prevalence of diabetes mellitus and obesity. These characteristics may be explained by in part their working environment. 相似文献
994.
A fairly high activity of a relatively heat-resistant thiaminase was detected and characterized from the pupae of an African silkworm Anaphe spp. which had been the putative cause of a seasonal ataxia and impaired consciousness in Nigerians. The thiaminase in the buffer extract of Anaphe pupae was type I (thiamin: base 2-methyl-4-aminopyrimidine methyl transferase EC 2.5.1.2), and the optimal temperature and pH were 70 degrees C and 8.0-8.5, respectively. Based on gel filtration chromatography, the molecules were estimated to be 200 kDa. Second substrates which could be utilized by the thiaminase were pyridoxine, amino acids, glutathione, taurine and 4-aminopyridine. Thiamin phosphate esters were inactive as substrates. This is the first report describing an insect thiaminase. Our results indicate the necessity of thorough heat treatment for the detoxification of the African silkworm, making the worm a safe source of high-quality protein. 相似文献
995.
996.
Phytoestrogens and prostate disease 总被引:6,自引:0,他引:6
997.
Primary Mitral Valve Sarcoma in Infancy 总被引:2,自引:0,他引:2
K. Itoh T. Matsumura Y. Egawa M. Watanabe T. Ohshio A. Ohta Y. Hayabuchi K. Seki 《Pediatric cardiology》1998,19(2):174-177
Primary cardiac sarcoma is a rare tumor, found especially in children, particularly in the left side of the heart. This report
describes a rare case of primary mitral valve sarcoma in a 7-month-old male infant with hemiparesis and heart murmur who underwent
mitral valve replacement because of excessive invasion of the mitral valve by the tumor. The patient remains well, free of
recurrence and cerebral metastasis, and without adjuvant therapy 18 months after the operation. 相似文献
998.
Akihiro Konno Miho Kudo Tsuyoshi Ichihara Masahiko Yamagami Seiki Horita Kazunori Ohama Kazuhisa Taketa Shoichi Koizumi 《Pediatrics international》1998,40(5):466-469
Abstract Background: Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years. 相似文献
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years. 相似文献
999.
1000.