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1.
2 10-year marriage cohorts from 2 surveys of married women in Melbourne were compared on their timing of the 1st and 2nd births. The results showed that women who were married in the early 1970s were much more likely to delay their first birth until about the 3rd or 4th year of marriage compared with women who married in the 1960s. This tendency to delay the 1st birth was probably aided by effective contraception, as it coincided with widespread use of the oral contraceptive. There was no difference in the timing of the 2nd birth in relation th the 1st birth between the 2 marriage cohorts. Women who delayed childbearing also preferred smaller families. Indeed, the increase in the % of women delaying childbearing appears to be synonymous with the trend toward the two-child family. Altough the number of married women in the labor force increased significantly from the early to the later cohort, a desire to work was not usually cited as the reason for delaying childbearing. Rather, economic reasons were most frequently mentioned for delaying childbearing. 相似文献
2.
We simulated gas transport due to cardiogenic oscillations (CO) using a model developed to quantify the gas mixing due to high-frequency ventilation (16). The basic components of the model are 1) gas mixing by augmented transport, 2) symmetrical lung morphometry, and 3) a Lagrangian (moving) reference frame. The theoretical predictions of the model are in general agreement with published experimental studies that have examined the effect of CO on the nitrogen concentration obtained by intrapulmonary gas sampling and the effect of CO on regional and total anatomical dead space. Further, the model predicts that augmentation of gas transport due to CO is less, nearer to the alveolar regions of the lung, and that the effect of CO during normal tidal breathing is negligible, but that CO may contribute up to approximately 10% of the alveolar ventilation in patients with severe hypoventilation. The agreement between experimental and theoretical results suggests that it may not be necessary to invoke gas transport mechanisms specific to an asymmetrical bronchial tree to explain the major proportion of gas transport due to CO. 相似文献
3.
A patient with renal failure developed hypermagnesaemia, with confusion, drowsiness, and dysarthria. Nevertheless, the dietary magnesium content was low, and investigation showed actual intracellular depletion of magnesium. The cause of this state is not known, though it is presumably connected with a failure to maintain the normal concentration gradient of magnesium across the cell wall. The clinical state and the serum magnesium level returned to normal after treatment with calcium gluconate. 相似文献
4.
Boon Seng Ooi Beatrice T. M. Chen Charles C. S. Toh Oon Teik Khoo 《BMJ (Clinical research ed.)》1970,3(5725):744-746
Of 127 hypertensive patients aged 12 to 40 investigated by intravenous pyelography, abdominal aortography, and renal biopsy an underlying cause was found in 57%. The proportion with secondary hypertension was higher in young patients and in those with severe hypertension. Primary arteritis of the aorta was an important cause of renovascular hypertension in an Asian population. 相似文献
5.
Noriko Takahashi Katsuyoshi Masuda Kenji Hiraki Kazuo Yoshihara Hung-Hsiang Huang Kay-Hooi Khoo Koichi Kato 《European journal of biochemistry》2003,270(12):2627-2632
To determine the glycoforms of squid rhodopsin, N-glycans were released by glycoamidase A digestion, reductively aminated with 2-aminopyridine, and then subjected to 2D HPLC analysis [Takahashi, N., Nakagawa, H., Fujikawa, K., Kawamura, Y. & Tomiya, N. (1995) Anal. Biochem.226, 139-146]. The major glycans of squid rhodopsin were shown to possess the alpha1-3 and alpha1-6 difucosylated innermost GlcNAc residue found in glycoproteins produced by insects and helminths. By combined use of 2D HPLC, electrospray ionization-mass spectrometry and permethylation and gas chromatography-electron ionization mass spectrometry analyses, it was revealed that most (85%) of the N-glycans exhibit the novel structure Manalpha1-6(Manalpha1-3)Manbeta1-4GlcNAcbeta1-4(Galbeta1-4Fucalpha1-6)(Fucalpha1-3)GlcNAc. 相似文献
6.
Khoo Kay-Hooi; Chatterjee Delphi; Caulfield John P.; Morris Howard R.; Dell Anne 《Glycobiology》1997,7(5):653-661
The granulomatous pathology in human intestinal schistosomiasisis induced primarily by the egg antigens of schistosome, a parasitictrematode. Glycolipids and glycoproteins were extracted fromthe eggs of the two major species which infect human, Schistosomamansoni and Schistosoma japonicum, for structural characterizationbased on highly sensitive mass spectrometric analysis coupledwith chemical derivatization. Here, we demonstrate that a seriesof uniquely multifucosylated glycosphingolipids constitute themajor egg glycolipids of S.mansoni but not of S.japonicum. TheS.mansoni glycosphingolipids were found to be extended by varyingnumbers of an unusual repeating unit, 相似文献
7.
J C Khoo D Steinberg E Y Lee 《Biochemical and biophysical research communications》1978,80(2):418-423
Diglyceride lipase of chicken adipose tissue was found to be activated by cyclic AMP-dependent protein kinase to the same extent as hormone-sensitive triglyceride lipase (3-to 10-fold) when lipase assays were carried out in buffers of low ionic strength. Sodium phosphate (50 mM) or sodium chloride (100 mM) preferentially enhanced the basal (nonactivated) form of diglyceride lipase, which minimized the apparent activation by protein kinase. The activated diglyceride lipase was readily deactivated by a pure protein phosphatase from bovine heart (MW 35,000) and the deactivated enzyme was then reactivated by protein kinase. 相似文献
8.
The Fps/Fes protein-tyrosine kinase promotes angiogenesis in transgenic mice. 总被引:8,自引:3,他引:8
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P Greer J Haigh G Mbamalu W Khoo A Bernstein T Pawson 《Molecular and cellular biology》1994,14(10):6755-6763
9.
The thermodynamic stability of a protein plays an important role during evolution and adaptation in order to maintain a folded and active conformation. p53 is a tumour suppressor involved in the regulation of numerous genes. Human p53 has an unusually low thermodynamic stability and is frequently inactivated by oncogenic missense mutations. Here, we examined the thermodynamic and kinetic stability of p53 DNA binding domains from selected invertebrate and vertebrate species by differential scanning calorimetry and equilibrium urea denaturation. There is a correlation in the apparent melting temperature of p53 with the body temperature of homeotherm vertebrates. We found that p53 from these organisms has a half-life for spontaneous unfolding at organismal body temperature of 10-20 min. We also found that p53 from invertebrates has higher stability, bearing more resemblance towards p63 and p73 from humans. Using structure-guided mutagenesis on the human p53 scaffold, we demonstrated that the amino acid changes on the protein surface and in the protein interior lead to the elevated stability of p53 orthologs. We propose a model in which the p53 DNA binding domain has been shaped by the complex interplay of different selective pressures and underwent adaptive evolution leading to pronounced effects on its stability. p53 from vertebrates has evolved to have a low thermodynamic stability and similarly short spontaneous half-life at organismal body temperature, which is related to function. 相似文献
10.
Khoo Kelvin H. P. Sheedy Jason G. Taylor Julian D. Croser Janine S. Hayes Julie E. Sutton Tim Thompson John P. Mather Diane E. 《Molecular breeding : new strategies in plant improvement》2021,41(12):1-13
Molecular Breeding - Plant height is vital for crop yield by influencing plant architecture and resistance to lodging. Although lots of quantitative trait loci (QTLs) controlling plant height had... 相似文献