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61.
Objective : To determine the relationship between lung function at 11 years of age and bronchopulmonary dysplasia (BPD) in very low birthweight (VLBW) children.
Methodology : This study comprised 154 consecutive surviving VLBW children, divided into three groups with respect to their neonatal respiratory morbidity: group I developed BPD; group II required assisted ventilation but did not develop BPD; and group III required no assisted ventilation. Lung function tests were measured on 120/154 (77.9%) children at 11 years of age. The relationship between various lung function variables and neonatal lung disease was analysed by multiple linear regression.
Results : Several lung function variables reflecting airflow were significantly diminished in the BPD group ( n = 15), and residual volume was significantly higher. Despite poorer lung function overall, few children in the BPD group had lung function abnormalities in the clinically significant range ( n = 2 [13.3%] with a forced expired volume in 1 s <75% predicted; n = 2 [13.3%] with a forced vital capacity <75% predicted; n = 1 [6.7%] with a residual volume/total lung capacity >35%). There were no significant differences in lung function variables between group II ( n = 41) and group III ( n = 64). Changes in lung function tests between 8 and 11 years did not vary significantly between the three groups.
Conclusions : VLBW children with BPD in the newborn period have poorer lung function at 11 years of age than other surviving VLBW children without BPD, although few have lung function abnormalities in the clinically significant range.  相似文献   
62.
The A-G polymorphism at codon 104 in the glutathione S-transferase P1 (GSTP1) gene was examined in 138 male lung cancer patients and 297 healthy controls. The patients had significantly higher frequency of the GG genotype (15.9%) and a lower frequency of AA (38.4%) than the controls (9.1% and 51.5%, respectively). The level of hydrophobic DNA- adducts were determined in lung tissue from 70 current smokers. Patients with the GG genotype had a significantly higher adduct level than patients with AA (15.5 +/- 10.2 vs 7.9 +/- 5.1 per 10(8) nucleotides, P = 0.006). We also analyzed the deletion polymorphism in the GSTM1 gene in 135 male patients and 342 controls. The patients were stratified according to histology, smoking dose, age, adduct level and mutational types found in the tumors (Ki-ras and p53 genes). The results consistently indicated that the GSTM1 null genotype was associated with a slightly increased lung cancer risk. When the combined GST M1 and P1 genotypes were examined, patients with the combination null and AG or GG had significantly higher adduct levels than all other genotype combinations (P = 0.011). The distribution of combined genotypes was also significantly different in cases and controls, mainly due to increased frequency of the combination GSTM1 null and GSTP1 AG or GG among patients.   相似文献   
63.
Follistatin is a specific binding protein which controls bioavailability of activins and inhibins which have an important role in fetal development. In the first trimester of pregnancy bioactive dimeric inhibins are found at high concentrations in the extra- embryonic coelomic fluid, but the distribution of follistatin and activins is not known. We have used recently developed immunoassays for follistatin, activin A and activin AB to determine their presence in the intrauterine compartments during early pregnancy. Follistatin was present in highest concentrations in the extra-embryonic coelomic fluid (11.72 +/- 1.70 ng/ml; median +/- SEM), with less in maternal serum (6.35 +/- 4.58) and lowest amounts in amniotic fluid (0.97 +/- 0.52). Follistatin concentrations in extra-embryonic coelomic fluid were highly correlated with both dimeric inhibin isoforms. Activin A was present in only barely detectable amounts in some samples of extra- embryonic coelomic fluid (41% of samples) and maternal serum (26%) and was undetectable in all amniotic fluid samples. Activin AB was undetectable in all compartments. The presence of follistatin in the amniotic and extra-embryonic coelomic fluids may regulate the availability of bioactive activins and inhibins which are released into the intrauterine compartments during the development of the fetus and placenta in early pregnancy.   相似文献   
64.
Smith  PJ; Jackson  CW; Dow  LW; Edwards  CC; Whidden  MA 《Blood》1980,56(1):52-57
Hypertransfusion can enhance recovery from neutropenia in certain clinical and experimental situations. We have studied the pattern of myeloid recovery in mice hypertransfused after receiving 350 rads whole body irradiation. Both hypertransfused and control groups showed the degenerative phase, abortive rise, and regenerative phase that has been described following sublethal irradiation. The blood granulocyte counts in the hypertransfused group returned to normal more rapidly and were maintained at a significantly higher level during the regenerative phase. This difference is not the result of a shift in granulocytes from the marrow granulocyte reserve or marginal granulocyte pool to the circulating pool, but is associated with significantly enhanced bone marrow granulopoiesis. While the total bone marrow cellularity of the hypertransfused mice is less than that of the control mice, the hypertransfused group contains more CFU-GM and myeloid cells during the regenerative phase. The enhanced granulopoiesis is not due to increased colony-stimulating activity (CSA) levels in the hypertransfused mice, as the CSA levels were significantly lower in this group compared to the controls prior to and during the initial phase of granulopoietic recovery. This study suggests that hypertransfusion increases the rate of recovery of myelopoiesis by increasing the number of precursors available for myeloid differentiation from an earlier stem cell compartment.  相似文献   
65.
The postoperative diagnostic imaging examinations of 44 children who underwent 59 orthotopic liver transplantations were reviewed. The imaging modalities used for the evaluation of suspected complications include plain roentgenography, ultrasonography (US), computed tomography (CT), nuclear scintigraphy, arteriography, percutaneous and operative cholangiography, and endoscopic retrograde cholangiopancreatography. The main postoperative complications included ischemia, thrombosis (hepatic artery and portal vein), infarction, obstruction or leakage of the biliary anastomosis, hepatic and perihepatic infection, and allograft rejection. US, the most frequently used abdominal imaging modality, was best suited for detection of biliary duct dilatation, fluid collections in or around the transplanted liver, and hepatic arterial, inferior vena caval, and portal vein thrombosis. CT was especially helpful in corroborating findings of infection and in locating abscesses. Technetium 99m sulfur colloid (early- and late-phase imaging) provided a sensitive, although nonspecific, means of assessing allograft vascularization and morphology. Angiography showed vascularity most clearly, and cholangiography was the most useful in the assessment of bile duct patency. A diagnostic imaging algorithm is proposed for evaluation of suspected complications.  相似文献   
66.
Short rib-polydactyly syndrome type 3   总被引:3,自引:0,他引:3  
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67.
68.
69.
Adams  PS  Jr; Roub  LW 《Radiology》1984,151(1):81
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70.
Two experiments examined the effects of various doses of l-amphetamine on locomotor activity, two-way avoidance, and intertrial responses in rats that were 15, 17, 21, 36, and 90 days of age. In the first experiment, testing began 20 min after drug administration and 100 avoidance trials were given. In the second experiment, testing began immediately after drug treatment and 200 trials were given. In the two youngest groups, shuttle crossings during adaptation were increased by the highest doses. The typical inverted U-shaped function between amphetamine dose and locomotor activity found in adults began to emerge at 36 days of age. Generally, at the two youngest ages, there was a dose-related increase in avoidance and intertrial responses on the first few blocks of trials and then a decrease across trials. In 21-day rats, the drug increased avoidance on the first few trial blocks but acquisition was altered only slightly. Acquisition of 36-and 90-day rats was increased, but this increase was greater in adults. It appears likely that development of CNS catecholaminergic neurons is responsible for the age-dependent behavioral effects of l-amphetamine.  相似文献   
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