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961.
Drug Enforcement Administration's (DEA) Cocaine Signature Program previously identified 19 coca-growing regions within South America and developed methodology to geo-source cocaine using a combination of trace cocaine alkaloids, stable isotopes, and multivariate statistics. Twenty-nine coca leaf samples collected in 2016 and 2019 from a previously unanalyzed coca-growing region located in Puno, Peru, were analyzed with this methodology. Trace cocaine alkaloids and stable isotopes were compared with other Peruvian regions. Minor differences were observed in the extracted cocaine alkaloid profiles when compared with samples collected from the Ucayali-Huallaga Valley and Cusco-Apurimac regions while the stable isotopes of δ2H (−177.1‰) and δ18O (23.8‰) were enriched. Puno's alkaloid and stable isotope results are presented in this publication to assist forensic laboratories and enhance their cocaine geo-sourcing capabilities.  相似文献   
962.
The sustained and localized delivery of monoclonal antibodies has become highly relevant, because of the increasing number of investigated local delivery applications in recent years. As the local delivery of antibodies is associated with high technological hurdles, very few successful approaches have been reported in the literature so far. Alginate-based delivery systems were previously described as promising sustained release formulations for monoclonal antibodies (mAbs). In order to further investigate their applicability, a single-dose animal study was conducted to compare the biocompatibility, the pharmacokinetics and the bioavailability of a human monoclonal antibody liquid formulation with two alginate-based sustained delivery systems after subcutaneous administration in rats. 28 days after injection, the depot systems were still found in the subcutis of the animals. A calcium cross-linked alginate formulation, which was injected as a hydrogel, was present as multiple compartments separated by subcutaneous tissue. An in situ forming alginate formulation was recovered as a single compact and cohesive structure. It can be assumed that the multiple compartments of the hydrogel formulation led to almost identical pharmacokinetic profiles for all tested animals, whereas the compact nature of the in situ forming system resulted in large interindividual variations in pharmacokinetics. As compared to the liquid formulation the hydrogel formulations led to lower mAb serum levels, and the in situ forming system to a shift in the time to reach the maximum mAb serum concentration (Tmax) from 2 to 4 days. Importantly, it was shown that after 28 days only marginal amounts of residual mAb were present in the alginate matrix and in the tissue at the injection site indicating nearly complete release. In line with this finding, systemic drug bioavailability was not affected by using the controlled release systems. This study successfully demonstrates the suitability and underlines the potential of polyanionic systems for local and controlled mAb delivery.  相似文献   
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964.
Book reviews     
History

The End of History and the Last Man By Francis Fukuyama. Hamish Hamilton, London, 1992, 418 pp., £20.00, ISBN 0–24–1301–1

Aeskulap oder Mars? [Asdepius or Mars] (subtitle: Doctors against War) Edited by T.M. Ruprecht and C. Jenssen. (In German). Donat Verlag, Bremen, 1991, 604pp., 48.00DM, ISBN 3–924444–51‐X.

The Gulf War

Hidden Casualties, Volume II: The Environmental, Health and Political Consequences of the Persian Gulf War Edited by Saul Bloom, John M. Miller and Philippa Winkler, with Ross Mirkarimi. ARC/Arms Control Research Center, 942 Market St, Suite 202, San Francisco CA 94102, USA, 1993, 350pp.

Medicine and War

Wounded Healthy Cities: Searching for Health and Human Dignity A report by the Croatian Healthy Cities Network. Compiled by Ivana Eterovi?, Selma Sogori?, and Slobodan Lang. Edited by John Middleton. Sandwell Public Health Publications, 1992, PO Box 1953, Lyndon, West Bromwich, West Midlands, B71 4NA, pp. 68, £5.95 incl. p&;p, ISBN 0–9517035–4–4.

Public Health

Health through Public Policy, the Greening of Public Health Edited by Peter Draper. Greenprint, London, 1991, x + 258 pp., £9.99, ISBN 1–85425–045–0.

Economics

The Culture of Contentment By John Kenneth Galbraith. Sinclair Stevenson, London, 1992, 195pp., £14.95, ISBN 1–85619–147–8.

Beyond the Limits: Global Collapse or a Sustainable Future By Donella Meadows, Dennis Meadows and Jorgen Randers. Earthscan, London, 1992, xix + 300 pp., £19.95, ISBN 1–85383–130–1 (hbk), £11.95, ISBN 1–85383–131‐X (pbk).

Human Rights

Refugees: Rationing the Right to Life By David Keen. Zed Books, London, 1992, 86pp., £29.9S(hbk), ISBN 1–85649–091–2, £9.95(pbk), ISBN 1–85649–092–0.

Deadly Silence: Black Deaths in Custody Institute of Race Relations, London, 1991, 75pp., £4 (pbk), ISBN 085001–038–1.

Torture and Its Consequences: Current Treatment Approaches Edited by Metin Ba?o?lu. Cambridge University Press, Cambridge, 1992, xxiii + 527pp., £55.00, ISBN 0–521–39299–3

Militarism and the Environment

Taking Stock: The Impact of Militarism on the Environment Working Group on Militarism and the Environment. Science for Peace, 1992, 30pp., Can$ 4.00 (available from WGME, University College, University of Toronto, Ontario, Canada M5S 1A1).

AIDS

The AIDS Epidemic: Economic, Political and Security Implications By Alan Whiteside and David FitzSimons. Research Institute for the Study of Conflict and Terrorism, London, 1992, 43pp., £9.00, ISSN 0069–8792 (available from 136 Baker Street, London W1M 1FH)  相似文献   
965.
966.
ABSTRACT

Epidemiological studies in man suggest that blood pressures tend to be higher in persons with low calcium (Ca) intakes. Previous studies in normal rats have shown that severe Ca restriction raises blood pressure. The chronic effect of moderate Ca restriction is not known. We evaluated the effect upon systolic blood pressure of rearing young Wistar rats on a diet marginally adequate in Ca. Male weanling Wistar rats (8 rats per group) were placed on one of four diets containing 0.5% Ca (control diet), 0.4% Ca, 0.3% Ca, or 0.2% Ca. The three experimental diets were made up by replacing CaHPO4 in the salt mix with (NH4)H2PO4. Content of PO4 and electrolytes other than Ca was the same for all 4 diets. Sodium (Na) content was 0.1%. Diets were fed for 19 weeks. Rats did not grow normally on the 0.2% Ca diet, but growth was normal on the other three diets. There was no overall statistically significant effect of diet upon systolic pressure. During the first nine weeks of study there were no significant differences between groups and no consistent trends. During the last seven weeks, however, there was a consistent trend toward higher systolic pressures as Ca intake decreased. The mean change in blood pressure during the last five weeks of study from the baseline value at 4 weeks of age was significantly greater in rats consuming 0.2% Ca and tended to be greater in rats consuming 0.3 and 0.4% Ca than in controls. On several occasions, group mean systolic pressures were significantly greater in rats on the experimental diets than in controls. Systolic pressures for individual rats, averaged over the last seven blood pressure measurements, varied over a wider range in the experimental groups than in rats eating the control diet, and the distribution in the experimental groups was shifted toward higher systolic pressures. The results suggest that rearing normal rats on a diet marginally adequate in Ca may lead to a modest elevation in the blood pressures of some, but not all rats. The effect, however, is of much smaller magnitude than that observed with severe Ca restriction.  相似文献   
967.
This 24-week-long pilot investigation of 30 men and women with a BMI > 27 kg/m2 aimed to determine whether virtual gastric band (VGB) hypnotherapy has an effect on weight loss in overweight adults, compared to relaxation hypnotherapy and a self-directed diet. Levels of weight loss and gain ranged from ?17 kg to +4.7 kg in the VGB hypnotherapy group and ?9.3 kg to +7.8 kg in the relaxation group. There was no significant difference between VGB hypnotherapy as a main effect on weight loss, (X2 = 0.67, p = .41, df = 1) and there was no evidence of differential weight loss over time, (X2 = 4.2, p = .64, df = 6). Therefore, the authors conclude that there was no significant difference between VGB hypnotherapy and the relaxation hypnotherapy.  相似文献   
968.
969.
970.
After the 2011 declaration of rinderpest disease eradication, we surveyed 150 countries about rinderpest virus stocks. Forty-four laboratories in 35 countries held laboratory-attenuated strains, field strains, or diagnostic samples. Vaccine and reagent production and laboratory experiments continued. Rigorous standards are necessary to ensure that stocks are kept under safe conditions.  相似文献   
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