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V S Butt 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1972,353(2):131-132
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Polymorphonuclear neutrophils (PMN) in bovine uterine flushings following intrauterine deposition of killed bacteria were measured and the effect of immune status on the influx of PMN into the uterine lumen during oestrus was determined. Holstein heifers were immunized with a 270-kDa outer-membrane protein (omp-270) from Haemophilus somnus. During oestrus, immunized heifers (n = 21) received an intrauterine inoculum of either a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Five additional heifers were inseminated with extended bovine semen. Uterine contents were collected in saline lavage immediately before inoculation (t0) and at 6, 24, 48, 72, 96, and 120 h after inoculation. The semen-inoculated heifers were lavaged only at t120. All groups experienced PMN infiltration which peaked 6 h after inoculation and tended to decline thereafter. Differences were not observed between treatment groups, indicating that neither bacterial inoculation nor immune status was as important in eliciting PMN effusion as the flushing procedure itself. 相似文献
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The mu agonist morphine and the non-specific opioid antagonist naloxone both may accelerate feline colonic transit; the effects of morphine are dose dependent. Kappa and delta receptor function was studied in the present work. Colonic transit of a radionuclide marker instilled into the cecum was quantitated for 6 hr in a crossover study. The delta agonist [D-Pen2,D-pen5]enkephalin (1 mg/kg, i.m.) prolonged the cecum and ascending colon half-emptying time by 337% (P less than 0.05), and delayed the progression of the geometric center over time. The kappa agonist U-50,488 (1 mg/kg, i.m.) had no apparent effect on the cecum and ascending colon, but delayed filling of the descending colon. Loperamide, an antidiarrheal agent, also delayed colonic transit. Thus, selective opioid agonists have both site and functional differences in their effect on feline colonic transit. 相似文献
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The effect of cathinone and amphetamine on brown adipose tissue thermogenesis and its modification with propranolol and timolol has been studied in rats. Both cathinone and amphetamine produced significant dose dependent increases in intracapsular brown adipose tissue (IBAT) and rectal temperatures. Amphetamine was found to be three times more potent as compared to cathinone, on a dose basis. Pretreatment of animals with propranolol and timolol individually inhibited cathinone and amphetamine induced hyperthermia. These findings suggest the involvement of beta adrenergic receptors in cathinone and amphetamine induced thermogenesis. 相似文献
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Felicity Z. Watts Neil Butt Philip Layfield Jesse Machuka Julian F. Burke Anthony L. Moore 《Plant molecular biology》1994,26(1):445-451
An Arabidopsis thaliana gene (UBC6) encoding a homologue to ubiquitin-conjugating enzymes has been isolated which is capable of encoding a protein of 183 amino acids of ca. 21 kDa. Northern analysis indicates that the gene is expressed in flowers, seeds and, to a somewhat lesser extent, in 10-day seedlings but not in mature leaves, callus and pre-flowering plants. This pattern of expression is confirmed using transgenic Arabidopsis plants containing a UBC6 promoter-GUS gene fusion construct. These plants displey GUS activity in mature anthers prior to dehiscence, in developing embryos, sepals and the style after pollination. 相似文献
9.
Soraya C. M. Leal David J. Bertioli Brenda V. Ball Tariq M. Butt 《Biocontrol Science and Technology》1994,4(1):89-94
Nucleic acids from 41 strains of Metarhizium anisopliae, obtained from different parts of the world were extracted and examined by electrophoresis. Strong bands of double‐stranded RNA (dsRNA) were detected in two isolates from Brazil, V215 and V291, which had, respectively, 13 and 9 distinct bands ranging in size from ca. 0.75 to 3.5 kb. Icosahedral virus‐like particles (VLPs) (ca. 33 nm in diameter) were observed by transmission electron microscopy in extracts of these isolates. The VLPs and dsRNA were both absent from a clone of the isolate V291 which had been subcultured successively on solid medium. Bioassays against the aphid Myzus persicae showed no detectable difference in virulence between the clone of V291 which contained dsRNA and the clone that did not. 相似文献
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S Franks P M Horrocks S S Lynch W R Butt D R London 《BMJ (Clinical research ed.)》1983,286(6372):1177-1179
Twenty five patients with hyperprolactinaemia were treated with pergolide mesylate, a new dopamine receptor agonist. Twenty three received treatment for six to 20 months, and in all serum prolactin concentrations were considerably reduced. In most patients prolactin concentrations were maintained in the normal range by a low, once daily dose of pergolide and reversal of associated reproductive disorders was observed. Tumour volume as assessed by computed tomography decreased considerably during treatment in three out of four patients with a pituitary tumour. The drug was well tolerated. Side effects were similar to those of bromocriptine, but four out of eight patients who had been forced to stop taking bromocriptine because of untoward effects were subsequently able to tolerate treatment with pergolide. Pergolide mesylate promises to be a useful addition to the currently available long acting dopamine agonists in the management of hyperprolactinaemia. 相似文献