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11.
Neonatal polycythemia is a perinatal complication in infants of diabetic mothers. The cord CBC (complete blood counts), serum iron, transferrin and ferritin concentrations were studied in newborn infants of 9 GDM (gestational diabetes), 21 NIDDM (noninsulin-dependent diabetes mellitus), and 8 IDDM (insulin-dependent diabetes mellitus) mothers. The RBC (red blood cell) count, Hb (hemoglobin) and Hct (hematocrit) of these infants were higher than control infants. There was no difference between the serum iron concentration of the infants of each group diabetic mothers and the infants in the control group, but the transferrin concentration was significantly higher and the ferritin was significantly lower in the infants of diabetic mothers than in those of control mothers. There was a significant negative correlation between transferrin and ferritin (r = -0.491 p less than 0.001). Erythropoiesis is considered to be enhanced in the fetuses of diabetic mothers, and the iron needed for erythropoiesis is reportedly transported from the mother to the fetus according to the demands of the fetus, but the iron storage was shown to be reduced in the fetuses of diabetic mothers. 相似文献
12.
Reggiani Remo; Cantu Carlo Alberto; Brambilla Ida; Bertani Alcide 《Plant & cell physiology》1988,29(6):981-987
In excised rice roots, anaerobic degradation of proteins gaverise to an increase of free-amino acids. Anoxic accumulationof alanine, -aminobutyric acid and proline was the consequenceof the interconversion of glutamate, aspartate and amides. Theshift in the composition of the amino acid pool appears to becaused by changes in keto acid levels. The role of reactionsinvolved in amino acid interconversion and the physiologicalsignificance of these interconversions are considered and discussed. (Received November 25, 1988; Accepted June 9, 1988) 相似文献
13.
Peter Aaby Jette Bukh Ida Maria Lisse Maria Clotilde da Silva 《BMJ (Clinical research ed.)》1988,296(6631):1225-1228
The mortality from measles was studied in an urban area of Guinea-Bissau one year before and five years after the introduction of a vaccination programme. The years after the introduction of immunisation saw a decline in mortality among unvaccinated children with measles. This decline occurred despite a lower age at infection and an increasing prevalence of malnourished children. State of nutrition (weight for age) did not affect the outcome of measles infection. The incidence of isolated cases, however, increased in the period after the introduction of measles vaccination. As mortality was lower among these cases, diminished clustering explained some of the reduction in mortality. Comparison between the urban district and a rural area inhabited by the same ethnic group showed a lower age at infection, less clustering of cases, and lower case fatality ratios in the urban area.Endemic transmission of measles in urban districts leads to less clustering of cases, which may help explain the usually lower case fatality ratios in these areas. As measles vaccination increases herd immunity and diminishes clustering of cases, it may reduce mortality even among unvaccinated children who contract the disease. 相似文献
14.
15.
Water stress plating hypersensitivity of yeasts 总被引:4,自引:0,他引:4
Saccharomyces cerevisiae, when growing exponentially in batch culture, passed through a phase in which, on average, one cell in 10(4) survived plating onto a low water activity (aw) agar medium. Stationary phase cultures were resistant as were all other species tested, with the exception of Candida krusei. In continuous culture, S. cerevisiae was more resistant at low than at high dilution rates. Plating at low aw was lethal to those cells that were not protected by an adequate content of compatible solute. In naturally resistant yeasts and in S. cerevisiae that had been exposed to an adaptation process, the compatible solute was one or more types of polyhydric alcohol. Resistance in stationary phase was attributable to a different cause. 相似文献
16.
Assimilatory nitrate reductase (NR) from the cyanobacteriumPlectonema boryanum exhibits both ferredoxin (Fd)- and methylviologen (MV)-linked activities. Native (Fd-linked) activitywas reversibly inactivated by the exposure of a dithionite solutionof the enzyme to air, whereas MV-linked activity remained unaffected.Cyanate and azide, competitive inhibitors of NR, suppressedthe dithionite-induced inactivation, and the inactivation wasspecifically prevented by superoxide dismutase (SOD). Xanthineoxidase reaction inactivated Fd-linked activity but not MV-linkedactivity, and the native activity was protected by SOD and catalase.Photoactivated FAD/ EDTA irreversibly inactivated both Fd- andMV-linked activities, and the former activity was protectedby ascorbic acid. Dithionite-inactivated enzyme was restoredto its Fd-linked activity when incubated with cyanate or azidein the presence of dithionite or reduced Fd. Cyanide inactivatedboth Fd- and MV-linked activities when the enzyme was incubatedunder reducing conditions. The cyanide-inactivated enzyme wasalso reactivated by cyanate and azide under reducing conditions.It is suggested that superoxide and cyanide act as ligands tothe molybdenum center in the reversible inactivation of thenative activity of cyanobacterial Fd-NR. (Received March 3, 1986; Accepted May 30, 1986) 相似文献
17.
Changes in lipoxygenase (LOX) activity were followed duringthe germination of rice seeds. The enzyme activity of 3-day-oldseedlings was 20 times higher than that of ungerminated seeds.Sixty per cent of the increased activity was found in shoots.The increase in LOX activity was mainly due to an increase inlipoxygenase-2 (LOX-2), a minor component in ungerminated seeds;this increase was inhibited by cycloheximide. LOX-2 was isolatedfrom the 3-day-old seedlings and compared for its enzymologicalproperties with rice lipoxygenase-3 (LOX-3), a major componentin ungerminated seeds. Both LOX-2 and LOX-3 were stable at pH5 to 8, but LOX-2 was more heatstable than LOX-3. Apparent Kmvalues of LOX-2 and LOX-3 for linoleic acid were 170 and 59µM, and those for linolenic acid were 5,300 and 88 µM,respectively. Both LOXs were inhibited by some metal ions andantioxidants. (Received February 5, 1986; Accepted May 9, 1986) 相似文献
18.
Attenuating effect of diazepam on stress-induced increases in noradrenaline turnover in specific brain regions of rats: antagonism by Ro 15-1788 总被引:2,自引:0,他引:2
One-hour immobilization stress increased levels of the major metabolite of brain noradrenaline (NA), 3-methoxy-4-hydroxyphenyl-ethyleneglycol sulfate (MHPG-SO4), in nine brain regions of rats. Diazepam at 5 mg/kg attenuated the stress-induced increases in MHPG-SO4 levels in the hypothalamus, amygdala, hippocampus, cerebral cortex and locus coeruleus (LC) region, but not in the thalamus, pons plus medulla oblongata excluding the LC region and basal ganglia. The attenuating effects of the drug on stress-induced increases in metabolite levels in the above regions were completely antagonized by pretreatment with Ro 15-1788 at 5 or 10 mg/kg, a potent and specific benzodiazepine (BDZ) receptor antagonist. When given alone, Ro 15-1788 did not affect the increases in MHPG-SO4 levels. Behavioral changes observed during immobilization stress such as vocalization and defecation, were also attenuated by diazepam at 5 mg/kg and this action of diazepam was antagonized by Ro 15-1788 at 10 mg/kg, which by itself had no effects on these behavioral measurements. These findings suggest: (1) that diazepam acts via BDZ receptors to attenuate stress-induced increases in NA turnover selectively in the hypothalamus, amygdala, hippocampus, cerebral cortex and LC region and (2) that this decreased noradrenergic activity might be closely related to relief of distress-evoked hyperemotionality, i.e., fear and/or anxiety in animals. 相似文献
19.
Kanji Ishizaki Asao Noda Mituo Ikenaga Kenji Ida Keiichi Omoto Yusuke Nakamura Ken-ichi Matsubara 《Human genetics》1985,71(3):261-262
Summary The plasmid clone which contains human salivary amylase cDNA was used to detect restriction fragment length polymorphisms
(RFLPs). After double digestion with Pst 1 and Bam H1, a polymorphism with two alleles was observed. In Japanese, frequencies of these alleles, tentatively called 5.7kb and 6.5kb
fragment alleles, are 0.55 and 0.45, respectively. 相似文献
20.
A sensitive and specific assay method for cysteine sulfinic acid (CSA) and cysteic acid (CA) using high-performance liquid chromatography has been developed. The method includes post-column derivatization of various amino acids with o-phthalaldehyde in the presence of 2-mercaptoethanol. The column packed with cation-exchange resin (, Shimadzu Sci entific instruments, Inc., Kyoto, Japan) was used for obtaining general separation of amino acids except CSA and CA, while the separation of CSA and CA was achieved using a strong-base anion exchange (, Shimadzu Scientific Instruments) column. The fluorescence peak area for CSA was linear between 20 pmol and 5 nmol, whereas that for CA was 10 pmol to 5 nmol. The regional distribution of CSA, CA, and other amino acids in the rat brain was studied using this new assay method. 相似文献