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Urinary TXB2 excretion was measured during pregnancy and labor using high pressure liquid chromatography and radioimmunoassay. From the first trimester onwards TXB2 levels in urine of pregnant women (n = 60) were significantly (p less than 0.001) higher than in non-pregnant women (n = 12) and they increased, albeit not significantly, with advancing gestation. Labor was associated with a two-fold increase in urinary TXB2 excretion. Levels in established labor were significantly higher than at any other time in pregnancy (p less than 0.001), but the levels in incipient labor showed considerable overlap with these in late pregnancy. Thus urinary TXB2, while not necessarily originating from the pregnant uterus, appears to reflect the uterine activity of labor and may be the expression of a general stimulation of prostanoid production during parturition. 相似文献
3.
Cloning and sequencing of the peroxisomal amine oxidase gene from Hansenula polymorpha 总被引:7,自引:0,他引:7
P G Bruinenberg M Evers H R Waterham J Kuipers A C Arnberg G AB 《Biochimica et biophysica acta》1989,1008(2):157-167
We have cloned the AMO gene, encoding the microbody matrix enzyme amine oxidase (EC 1.4.3.6) from the yeast Hansenula polymorpha. The gene was isolated by differential screening of a cDNA library, immunoselection, and subsequent screening of a H. polymorpha genomic library. The nucleotide sequence of a 3.6 kilobase stretch of DNA containing the amine oxidase (AMO) gene was determined. The AMO gene contains an open reading frame of 692 amino acids, with a relative molecular mass of 77,435. The 5' and 3' ends of the gene were mapped and show that the transcribed region measures 2134 nucleotides. The derived amino-acid sequence was confirmed by sequencing an internal proteolytic fragment of the purified protein. Amine oxidase contains the tripeptide sequence Ser-Arg-Leu, located 9 residues from the carboxy terminus, which may represent the topogenic signal for protein import into microbodies. 相似文献
4.
Biological sensors are becoming more important to monitor the quality of the aquatic environment. In this paper the valve movement response of freshwater (Dreissena polymorpha) and marine (Mytilus edulis) mussels is presented as a tool in monitoring studies. Examples of various methods for data storage and data treatment are presented, elucidating easier operation and lower detection limits. Several applications are mentioned, including an early warning system based on this valve movement response of mussels. 相似文献
5.
Urinary excretion of 6-keto-PGF1α was measured by high pressure liquid chromatography and radioimmunoassay at various stages of pregnancy and labor. In the first trimester of pregnancy, urinary 6-keto-PGF1α concentrations were nor different from those measured before pregnancy, but they showed a significant increase in the second trimester of pregnancy (p <0.001). The levels rose further in the third trimester, although this increase was not statistically significant when compared to levels obtained in the second trimester. There was no evidence for a significance change in 6-keto-PGF1α excretion with the onset of labor. During well-established, progressive labor mean values of 6-keto-PGF1α excretion were about twice as high as before the onset of labor, but the range of values during labor was so wide that there was no statistical difference with values obtained in the second half of pregnancy.It is concluded that the increase in the urinary excretion of 6-keto-PGF1α occurs later in pregnancy than the increase in TXB2 excretion and that labor at term is not associated with marked changes in 6-keto-PGF1α excretion. 相似文献
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In a specified pathogen free (SPF) breeding colony of IIIVO/JU rabbits 8 cases of prolapsus vaginae occurred in 5 years. Clinically the animals were in shock. Haematocrits ranged from 9 to 15%. The prolapses started from the submucosal layer of the proximal part of the vestibulum vaginae. The prolapsed tissue consisted of over-expanded blood-sinuses. Between the sinuses signs of an inflammatory reaction were present. All 8 animals were in a period of increasing sexual activity when the prolapse developed. The 8 rabbits were closely related, indicating a possible hereditary defect. 相似文献
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G. D. Vogels C. van der Drift C. K. Stumm J. T. M. Keltjens K. B. Zwart 《Antonie van Leeuwenhoek》1984,50(5-6):557-567
Methanogenesis involves a novel set of coenzymes as one-carbon and electron carriers. Consequently, metabolic processes of
methanogens deviate from those present in non-methanogenic bacteria. Methanogenic bacteria can be classified on the basis
of substrate utilization. Group I (24 species) grows at the expense of hydrogen plus CO2 and/or formate and group II (7 species) uses methanol and/or acetate. Hydrogen-consuming methanogens are found as epi- or
endosymbionts of anaerobic ciliates. 相似文献