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151.
Given the changes of gender roles in this century it is hardly justified to assume constant proportions of alcohol consumption for males and females. The purpose of the study was to reconstruct the consumption trends of males and females in Switzerland since the beginning of the 20th century. Cirrhosis mortality and survey data were used to disaggregate by sex the per capita alcohol consumption based on liver cirrhosis mortality suggests that the evolution of alcohol consumption in Switzerland followed a parallel course for both sexes only until the 1930 s. The low consumption during World War II and the evident increase until the beginning of the '60s seem to have resulted above all from the variations in consumption of beer by men. The decrease in total alcohol consumption observed since the '70s is also most probably due only to men; there is no indication of a decreasing consumption by women. The tendency of male and female consumption patterns to become more similar should be taken into account in the prevention of alcohol misuse. 相似文献
152.
Gerhard Scherer 《Psychopharmacology》1999,145(1):1-20
Rationale: Compensation or compensatory smoking, accurately defined, deals with the question of whether switching to cigarette brands
with different smoke yields is associated with a change in smoke uptake proportional to the change in machine-derived yields.
The issue of compensation is important because it bears on whether switching to ”lighter” brands means lower overall smoke
intake or not. Objectives: The present review investigated whether and to what extend low yield cigarettes are smoked more intensively. In addition,
published data on whether nicotine, ”tar”, or any other smoke constituent or property influence compensational smoking are
summarized. Methods: The studies on compensation were classified as follows: (1) studies on smoking behaviour in relation to cigarette yields
(with and without brand switching); (2) studies on compensation for nicotine (switching between cigarettes which differ ”only”
in their nicotine yield, nicotine supplementation, manipulation of renal nicotine excretion, administration of nicotine agonists
or antagonists); (3) studies on compensation for other factors (influence of tar, taste, irritation, draw resistance). In
order to quantify the degree of compensation, an index is defined and applied to selected brand switching studies. This compensation
index determines, in relative units, the degree to which a smoker responds to a change in smoke yields with a change in smoke
uptake measured by suitable biomarkers. The role of vent blocking is also briefly discussed. Results: Most of the studies which compare the smoking behaviour when smoking cigarettes with different smoke yields supply evidence
for ”partial” compensation, suggesting that cigarettes with lower yields are smoked more intensively than those with higher
yields. These studies also show that a change in the daily number of cigarettes is not a common mechanism of compensation.
Effective vent blocking during smoking is a rare event and can therefore also be regarded as an uncommon mechanism of compensation.
Evaluation of a suitable subset of brand-switching studies revealed an average compensation of 50–60% of the nicotine yield.
Compensation tended to be more complete when changing to cigarettes with higher yields than when changing to cigarettes with
lower yields. In general, brand-switching studies do not supply information on the underlying causal factors responsible for
compensatory smoking. Results of the nicotine supplementation studies are not conclusive: some report evidence of nicotine
titration, others do not. A general problem with this type of investigation is that continuous nicotine application does not
mimic the spike-wise application with cigarette smoking, and may lead to nicotine tolerance. There is limited evidence that
cigarettes were smoked more intensively when the urinary clearance of nicotine was increased. A small number of studies provide
some evidence that smoking intensity increased after smokers were administered a nicotine antagonist. Several reports indicate
that tar, taste and sensory properties of the smoke as well as the draw resistance of the cigarette may play a role in compensatory
smoking. Low-yield cigarettes usually have reduced pressure drops which smoke researchers have suggested leads to increased
puff volume. This effect seems to be independent of the smoke yield of the cigarette. There is also some evidence that some
smokers maintain a consistent pattern of smoking which works independent of any changes in nicotine or tar yields, taste or
design features of the cigarette (”functional autonomy”). Conclusions: The available data suggest that smokers partially compensate for a different smoke yield. While the factors and their interaction
responsible for compensational smoking are not fully understood, there are data suggesting that a subgroup of smokers may
partially compensate for nicotine. Even in this subgroup of smokers, however, the relative importance of the pharmacological
versus the sensory effects of nicotine in smoke remains to be determined.
Received: 4 January 1999 / Final version: 22 March 1999 相似文献
153.
154.
Frank Rösch Hans Herzog Cornelius Plag Bernd Neumaier Ulrike Braun Hans-Willhelm Müller-Gärtnere Gerhard Stöcklin 《European journal of nuclear medicine and molecular imaging》1996,23(8):958-966
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure - emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for90Y, with detection by positron emission tomography (PET). The study compared the properties of two different86Y complexes —86y-citrate and86Y -ethylene diamine tetramethylene phosphonate (EDTMP) — in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing90Y. In 1 cm3 of bone metastasis, doses of 26±11 mGy/MBq and 18±2 mGy/MBq were determined per MBq of injected90Y- citrate and90Y- EDTMP, respectively. The doses to the bone marrow were 2.5±0.4 mGy/MBq for90Y- citrate and 1.8±0.6 mGy/MBq for90Y-EDTMP.86Y and PET provide quantitative information applicable to the clinical use of90Y. This method may also be useful for the design of other90Y radiopharmaceuticals and for planning radiotherapy dosages. 相似文献
155.
Gerhard Stöhrer 《Archives of toxicology》1991,65(7):525-531
Arsenic is a human carcinogen that in small amounts is widely distributed in food and water. It has been regulated for almost 100 years worldwide and in the United States, on the judgment of the Royal Commission on Arsenic that a classical threshold of toxicity exists and that a daily intake of 400 (g/day is safe. Modern regulatory thinking in the United States has not accepted safe levels for carcinogens and is thus in conflict with the arsenic standard. Recent epidemics of arsenicism have quantitatively confirmed that threshold not only for the non-cancerous arsenical skin lesions but also for arsenical skin and internal cancers. Research shows that arsenic is a general gene inducer. Genes induced are involved in proliferation, recombination, amplification and the activation of viruses. This characterizes arsenic as anindirect carcinogen and provides a molecular basis for risk assessment and the observed threshold dose response. In the United States at present, about 300 cases of occupational arsenical cancer, declining in numbers, are known. Background arsenic below the drinking water standard is not known to have produced disease. The conspicuous nature of arsenical skin disease presents an unusual opportunity for a simplified survey of arsenical skin disease to support regulatory standards for arsenic. 相似文献
156.
G. Ehninger B. Proksch H. Schmidt P. Waidelich B. Eichel R. Dopfer 《Cancer chemotherapy and pharmacology》1991,28(3):214-216
Summary The pharmacokinetics of etoposide following a new method of administration was determined. Undiluted etoposide was given at a dose of 30 mg/kg as part an intensified conditioning regimen prior to bone marrow transplantation. A terminal half-life of 3.4±0.7 h and a volume of distribution of 15.4±9.61 were found (n=8); the AUC was 764±302 g h ml–1. As compared with those obtained in other pharmacokinetic studies using etoposide diluted in normal saline, our data reflect full systemic bioavailability and unaltered pharmacokinetics. The application of undiluted etoposide makes the therapy easier and less time-consuming and avoids a high fluid volume and a high saline load. 相似文献
157.
Kurt Krejcy Gunther Krumpl Hannes Todt Gerhard Raberger 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(2):213-218
Summary The aim of the present study was to investigate the dose-dependent antiarrhythmic efficacy of lidocaine against electrically induced tachycardias in conscious, chronically instrumented postinfarction dogs. Programmed electrical stimulation (PES) was performed in 16 dogs 8 to 21 days after a 4 h occlusion of the left anterior descending coronary artery (LAD). Infusion of saline in 8 control animals with sustained ventricular tachycardia (SVT) inducible at baseline did not affect subsequent inducibility. In the treatment group 7 of 8 animals responded with SVT and one exhibited ventricular fibrillation at baseline. After an initial bolus of 1 mg/kg lidocaine intravenously (i.v.), the drug was infused at infusion rates of 40, 80 and 120 g/kg/min (i.v.). During 80 g/kg/min lidocaine (mean plasma level 3.5 g/ml) 7 out of 8 animals displayed an antiarrhythmic response; both the lower and the higher infusion rate were associated with a smaller antiarrhythmic efficacy (3 of 8 animals responded to 40 g/kg/min and 4 of 8 to 120 g/kg/min). Licocaine did not affect ventricular refractory periods, but induced an increase in intraventricular conduction time at all infusion rates, from 66.2 ms at baseline to 67.7 ms (p<0.05), 67.7 ms (p<0.05), 70.0 ms (p<0.01) respectively.In conclusion the present study demonstrates that lidocaine is of considerable value in the management of PES-induced ventricular arrhythmias in the postinfarction phase. However there is only a small optimal therapeutic plasma level range, where lidocaine exhibits its antiarrhythmic efficacy against this type of arrhythmia; this makes a carefully titration of the drug necessary both in the experimental and in the clinical setting.
Send offprint requests to K. Krejcy at the above address 相似文献
158.
Hans Christian Blossey Hans Helge Bartsch Dietrich Kanne Johannes Koebberling Gerhard Arno Nagel 《Cancer chemotherapy and pharmacology》1982,8(1):77-81
Summary Oral MPA 1.5 g/day leads to plasma concentrations between 1 and 12 g/ml, with a broad intra-and interindividual variance. The plateau state is reached in between 4 and 16 days. Plasma concentrations in the plateau state are very sensitive to dose modifications. After cessation of administration, the decline in plasma levels seems to proceed in two phases, with half-times of about 20 h and 4 days. Extraction procedures reveal no benefit in discriminating between MPA and its metabolites. 相似文献
159.
Gerhard Kloss Margret Leven 《European journal of nuclear medicine and molecular imaging》1979,4(3):179-186
Because tyrosine and dopa can be regarded as precursors of adrenomedullary hormones and melanin, radioiodinated derivatives of these compounds were tested for their accumulation in the adrenal medulla and in melanomas of various animal species. The highest level of accumulation in the adrenal medulla was attained in mice and rats with iodinated -hydroxy--methyltyramine, and in melanomas of mice with iodinated -methyltyrosine. The results could not be reproduced to the same extent in other species. 相似文献
160.
Gerhard Megges 《International journal of legal medicine》1979,83(1):81-85
Zusammenfassung Es wird über die Kasuistik und die toxikologischen Untersuchungen im Fall einer Selbsttötung durch Trinken von Castrol®-Bremsflüssigkeit berichtet. Zum Nachweis und zur quantitativen Bestimmung des Giftes hat sich die Gaschromatographie als vorteilhaft erwiesen. 相似文献