The effect of the gastrointestinal hormones on small intestinal motility and blood flow

Zusammenfassung Nachweis, dass Pentagastrin und CCK, in physiologischen Dosen bei der Katze infundiert, nur geringfügige Durchblutungseffekte im Dünndarmgebiet zeigen, während Sekretin über einen offenbar verschiedenen Mechanismus die Durchblutung erhöht.     

Enhancement of electrically stimulated guinea-pig gallbladder contraction by subthreshold concentrations of gastrointestinal hormones in vitro

Summary Concentrations of the octapeptide of cholecystokinin and pentagastrin, which alone do not contract the gallbladder, enhance the gallbladder contraction in response to electrical stimulation in vitro.Supported by grants from the Deutsche Forschungsgemeinschaft and the Alfred Teufel-Foundation.     

Skeletal lesions following ingestion of fluoridated water

Zusammenfassung Mit Hilfe der Röntgenmikroskopie wurde bei Ratten, die während 9–12 Monaten Wasser mit einem Fluorgehalt von 20–40 mg/l getrunken hatten, Veränderungen in der Mineralisierung der Wirbelsäule nachgewiesen. Die Veränderungen sind mit makroskopischer Röntgenuntersuchung nicht nachweisbar.     

Natriuretic peptide hormones promote radial water movements from the xylem of Tradescantia shoots

Immunological evidence suggests that plants, like vertebrates, contain natriuretic peptides (NPs) and that rat atrial NP (rANP) binds specifically to plant membranes and promotes concentration and conformation-dependent stomatal opening. Stomatal opening and specific increases in cGMP levels were also observed in response to immunoreactive plant NP (irPNP). Here we report that both 1 μM rANP and irPNP (100 ng total protein/100 μL) significantly increase radial water movements out of the xylem of shoots of Tradescantia multiflora. Enhanced radial water movements are also observed in response to the cell permeant cGMP analogue 8-Br-cGMP (100 nM). The water channel inhibitor mercuric chloride (HgCl₂) significantly inhibits radial water movements at concentrations of 50 μM, while the presence of 10 μM 2-hydroxyethylmercaptoethanol (ME) prevents the inhibitory effect of the mercurial. The guanylate cyclase inhibitor LY 83583 at a concentration of 20 μM and sodium azide (NaN₃) at concentrations of ≥ 1 μM both also reduce radial water movements. We therefore conclude that the regulation of radial water movement out of the xylem involves modulation of cGMP levels, water channels and respiration-dependent processes. In addition, we propose that NPs have a critical role to play in radial water movements out of the xylem and speculate that as in vertebrates, NP effects might, at least in part, be mediated via the regulation of guanylate cyclases and water channels. Received 15 June 1998; received after revision 7 August 1998; accepted 26 August 1998     

Inhibition of adrenal cortical hormones by an extract of lymphoid tissue

Résumé Les résultats obtenus indiqueraient une relation étroite entre le tissu lymphatique et les glandes endocrines, l'hypophyse et les corticosurrénales. Les auteurs suggèrent la possibilité d'un système endocrinaire, comprenant l'hypothalamus, l'hypophyse, les surrénales et le tissu lymphatique.     

Forecasting market potential and market penetration of residential water heater load control programs

This paper presents a model which estimates market potential and forecasts market penetration for one demand-side management (DSM) programwater heater load controlin the service territory of Virginia Power Corporation, a large electric utility in the south-eastern United States. Water heater load control is a voluntary program where customers are paid a monthly incentive to allow the utility to shut off power to their electric water heaters during periods of peak demand. Reducing the level of peak demand through DSM programs is one way for utilities to avoid building new power plants. The current total energy (or demand) impact due to a load control program is the sum of the changes in energy (or demand) for all program participants. The projected energy and demand impact due to a load control program is the average change per participant multiplied by the number of participants or adopters of the program. While it is reasonably straightforward to measure the energy savings resulting from shutting off power to a water heater, the more difficult task for planning purposes is forecasting the number of customers who will actually join the program (i.e. the market penetration) for a given incentive. The customer decision process is divided into three stages: eligibility, awareness, and adoption. The responsiveness of market penetration to changes in advertising and incentive amounts is demonstrated. In addition, the impact of changing advertising and incentive amounts on the percentage of aware customers who adopt the program and on that of eligible customers who become aware of the program is estimated. This model can be used by utility planners and managers to forecast the market penetration of both new and existing load control programs. In addition, it can be employed to estimate the impact of various promotion and marketing schemes on both market potential and market penetration.     

Theophylline plasma levels following the oral and rectal administration of theophyllinep-aminobenzoate of piperazine

Zusammenfassung Nach Verabreichung von Theophyllin (alsp-Aminobenzoat-piperazin) in Form von Tabletten und Zäpfchen wurden bei einigen Versuchspersonen spektrophotometrisch Plasmakonzentrationen bestimmt.     

Effect of an oral contraceptive on plasma dehydroepiandrosterone concentrations

Summary Plasma concentrations of dehydroepiandrosterone were measured in women by radioimmunoassay. It was found that a single dose of a combination type oral contraceptive Minovlar^® reduced dehydroepiandrosterone concentrations significantly.We would like to thank Dr M.L'E. Orme for helpful discussions.     

Glycerylphosphorylarsenocholine and phosphatidylarsenocholine in yelloweye mullet (Aldrichetta forsteri) following oral administration of arsenocholine

Summary The novel arsenical glycerylphosphorylarsenocholine has been isolated from yelloweye mullet (Aldrichetta forsteri) following oral administration of arsenocholine. Ether-soluble arsenic was shown to be present as phosphatidylarsenocholine.     

Biliary excretion and metabolism of14C cimetidine following oral administration to male and female rats

Summary In rats, the bile is not a major route of excretion of cimetidine or its metabolites, since only 10% of the¹⁴C associated with an oral dose of labelled cimetidine was excreted in the bile during 8 h after dosing.     

Total synthesis of oestrogenic hormones

Zusammenfassung Die Totalsynthesen von (±)-Östron, (±)-d-homo-Equilenin-methyläther und (±)-iso-Equilenin werden beschrieben.

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Acknowledgments. We thank the Department of Scientific and Industrial Research for the award of maintenance grants.