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71.
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P. P. Mathur Ramesh Prasad D. K. Hazra A. K. Shukla Ajay Kalra Prabhat Kumar R. Dayal Anil Kumar 《Indian journal of pediatrics》1986,53(3):401-404
Serum T4 and T3 were measured in 31 newborns of gestational ages 32–43 weeks. Out of 31, 11 were term, 12 preterm and 8 postterm. Blood samples
were taken from cord blood and from peripheral vein at 24 and 72 hours of age. Serum T4 and T3 values were low in cord blood samples, raised in 24 hours samples and then declined in 72 hour samples. In pretern newborns
cord T4 and T3 values were significantly lower and there was a blunted rise and fall in 24 and 72 hours samples as compared to term newborns.
In post term newborns cord serum T4 and T3 values were significantly raised while in peripheral vein samples difference was statistically insignificant as compared
to term newborns. This high incidence of low cord values and transient hypothyroxinemia observed in preterm and postnatal
surge of T4 may give rise to false results while screening for hypothyroidism. 相似文献
73.
Chatterjee K Hazra A Dollimore D Alexander KS 《Journal of pharmaceutical sciences》2002,91(4):1156-1168
The objective of this study was to develop and analyze an analytical method in order to evaluate preformulation candidates by their thermodynamic parameters and evaporation characteristics. Ortho, meta and tere-phthalic acids were chosen as model compounds. The relative advantages and disadvantages of a rapid thermogravimetric method have been studied in detail, which would aid in the preformulation characterization for pharmaceuticals. Methyl paraben was taken as the model compound for calibration, as its evaporation characteristics are well known. Using the Antoine and the Langmuir equation for evaporation conjointly, the parameter k, known as the coefficient of evaporation was determined. The value for this constant was validated by three methods simultaneously. Previously the use of such methods for compounds having uninhibited zero order evaporation has been documented. In the present study, phthalic acid was chosen as the model compound since its evaporation is a two-step overlapping phenomenon. In this study we have shown the use of Pressure Differential Scanning Calorimetry in separating such simultaneous endothermic processes. The Clausius-Clapeyron equation seemingly has anomalous behavior for vapor pressure over high temperature ranges. In this study a modification of the equation has been suggested to take into account the changes in the heat capacities that result due to high temperature effects. This study aims at documenting a concise method for rapid pharmaceutical characterization and suggests modifications for some basic thermodynamic parameters over higher temperature ranges. 相似文献
74.
Induction of apoptosis in human cancer cell lines by diospyrin,a plant-derived bisnaphthoquinonoid,and its synthetic derivatives 总被引:2,自引:0,他引:2
Diospyrin, a bisnaphthoquinonoid natural product, and three synthetic derivatives have been tested for their action in four human cancer cell lines: acute myeloblastic leukemia (HL-60), chronic myelogenic leukemia (K-562), breast adenocarcinoma (MCF-7) and cervical epithelial carcinoma (HeLa). In cells grown in appropriate media several derivatives elicited cytotoxicity as assessed by Trypan Blue dye exclusion, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide reduction and DNA synthesis. Diethyl ether derivative (D7) was most effective in this regard while the parent compound diospyrin (D1) was least active (D7>D3>D2>D1). D7 was not cytotoxic toward normal human lymphocytes, suggesting its action is specific for tumor cells. On microscopic examination D7-treated cells exhibited characteristic morphological features of apoptosis, such as cell shrinkage and formation of apoptotic bodies. Fluorescent staining with propidium iodide revealed distinct chromatin condensation and nuclear fragmentation. The apoptotic index paralleled cytotoxic parameters, and fragmented DNA extracted free of genomic DNA displayed on gel electrophoresis a typical ladder pattern. D7-induced apoptosis was mediated via activation of caspase 3 and caspase 8. 相似文献
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Cocaine use in pregnancy in Amsterdam 总被引:1,自引:0,他引:1
BJ Smit K Boer AM van Huis ISE Lie-A-Ling SC Schmidt 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S404):32-35
To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found. 相似文献
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