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101.
The effect of the kallikrein inhibitor aprotinin on luteal function, uterine activity and parturition was studied in primigravid pregnant rats. Luteal function was monitored by the determination of serum progesterone levels. Aprotinin given daily from Day 19 to Day 22 of gestation had no effect on progesterone concentrations compared to saline-treated controls, but indomethacin delayed the decline in progesterone levels over the same time period. Aprotinin treatment had no effect on fetal and placental weights from Days 19 to 22 of gestation. Aprotinin infusion in Day-22 pregnant rats resulted in a reduction in uterine motility (studied by continuous recording in conscious rats by means of an intrauterine microballoon) in 10/12 rats. Continuous infusion of aprotinin into rats which had been allowed to deliver one young resulted in a significantly prolonged duration of parturition compared to that in saline-infused controls. In one rat the delivery process was completely arrested and recommended only when the infusion was stopped. Aprotonin had no effect on either the spontaneous or oxytocin-induced uterine contractions of the isolated Day-22 pregnant rat uterus. It is concluded that the kallikrein-kinin system in the late pregnant rat does not appear to be involved in the luteolytic process but may play a functional role in the control of uterine and/or cervical function before and during parturition.  相似文献   
102.
Bai  C.  Ge  Y.  Ashton  R. W.  Evans  J.  Milne  A.  Hawkesford  M. J.  Whalley  W. R.  Parry  M. A. J.  Melichar  J.  Feuerhelm  D.  Basler  P. Bansept  Bartsch  M. 《Plant and Soil》2019,442(1-2):311-321
Plant and Soil - The development of fertile patches within an infertile matrix is a common phenomenon in drylands. Shrub-centered expansion of fertile islands is generally attributed to processes...  相似文献   
103.
An extracellular beta-glucosidase was purified from culture filtrates of the wood-decaying fungus Daldinia eschscholzii (Ehrenb.:Fr.) Rehm grown on 1.0% (w/v) carboxymethyl-cellulose using ammonium sulfate precipitation, ion-exchange, hydrophobic interaction and gel filtration chromatography. The enzyme is monomeric with a molecular weight of 64.2 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and has a pI of 8.55. The enzyme catalyzes the hydrolysis of p-nitrophenyl-beta-D-glucopyranoside (PNPG) as the substrate, with a K(m) of 1.52 mM, and V(max) of 3.21 U min mg(-1) protein. Glucose competitively inhibited beta-glucosidase with a K(i) value of 0.79 mM. Optimal activity with PNPG as the substrate was at pH 5.0 and 50 degrees C. The enzyme was stable at pH 5.0 at temperatures up to 50 degrees C. The purified beta-glucosidase was active against PNPG, cellobiose, sophorose, laminaribiose and gentiobiose, but did not hydrolyze lactose, sucrose, Avicel or o-nitrophenyl-beta-d-galactopyranoside. The activity of beta-glucosidase was stimulated by Ca(2+), Co(2+), Mg(2+), Mn(2+), glycerol, dimethyl sulfoxide (DMSO), dithiothreitol and EDTA, and strongly inhibited by Hg(2+). The internal amino acid sequences of D. eschscholziibeta-glucosidase have similarity to the sequences of the family 3 beta-glucosyl hydrolase.  相似文献   
104.
There have been conflicting reports regarding the gene assignment of the high-molecular-mass envelope glycoprotein gp2 (gp300) of equine herpesvirus 1. Here, we provide an unequivocal demonstration that gp2 is encoded by gene 71. gp2 that was purified with a defining monoclonal antibody was cleaved internally to yield a 42-kDa protein encoded by gene 71. Amino acid composition data and N-terminal sequence analysis of a tryptic peptide identified gp2 as the product of equine herpesvirus 1 gene 71 with the SWISS-PROT database. Analysis of gp2's monosaccharide composition and the 42-kDa subunit showed that the high level of O glycosylation occurs on the serine/threonine-rich region upstream of the cleavage site.  相似文献   
105.
106.
Immunization schedules for the production of monoclonal antibodies to bovine insulin and porcine adreno-corticotrophic hormone (ACTH) have been investigated. Specifically, prime dose, prime route, pre-fusion boost dose and immune status have been evaluated for their effect on both the number of hybrids observed after fusion, and the proportion of wells containing antibody which bound to the immunogen. Although a single optimum protocol was not identified, the results indicate that spleen cells from mice primed at multiple sites should be used for fusion after the peak of the primary antibody response. Excessive hyperimmunization should be avoided. Dose regimes combining a low prime amount and a high pre-fusion boost amount or a high prime amount and a low pre-fusion boost amount (except in the presence of circulating antibody) were favoured. Monitoring of the immune response of animals used in fusion experiments is of paramount importance.  相似文献   
107.
108.
The heartwood of Dalbergia melanoxylon has yielded new examples of known neoflavanoid types. The isolates included 4-phenylcoumarins, (S)-4-methoxydalbergiones and benzophenones which have the corresponding oxygenation pattern. The structures of the extractives have been examined by physical methods, and confirmed by conversion to known compounds or by independent synthesis. A 2-cinnamylphenol (6) and 3-cinnamylflavan (7) were the only products in a condensation reaction in the attempted synthesis of the 4-methoxydalbergione (1b).  相似文献   
109.
The maximum axial growth pressure of roots of Lupinus albus cv Lublanc and Lupinus albus cv Lunoble (spring and autumn-sown cultivars respectively) were measured. The mean values were not significantly different with an overall mean value of 645 kPa. This value is not unusually large for plant roots and is surprising because lupins are known for their ability to penetrate strong soils. The autumn cultivar had a significantly greater maximum elongation rate under zero mechanical impedance than the spring cultivar. The impeded diameters were also larger in the autumn cultivars.  相似文献   
110.
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