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51.
Though much research about the public's views of scientists, genetic research and its moral, ethical, and social implications exists, little has been done to investigate how scientists view their own role(s) in public discussions and policy formation related to genetic research and technologies. We interviewed 20 academic geneticists in the United States about their perceptions of the roles they and others (e.g., professional societies, the public, ethicists, and elected officials) do and should play in the formation of science policy, the communication of science to the public, and the public discussions of moral and ethical issues raised by scientific advances. The participants in our study thought that scientists should be more actively involved in public outreach and science policy formation, but frequently they felt ill-equipped and unsupported by their peers and institutions to pursue these activities. Furthermore, many were skeptical of or did not trust elected officials--who they consider uninformed about the issues and too driven by political agendas--to formulate sound science policy. They do, however, have faith in the ability of scientific societies to influence policy effectively, and some thought that societies should play a larger role, both in science policy and as a liaison between scientists and the public. Finally, participants offered suggestions for increasing the involvement and influence of scientists in science-policy formation and public discourse.  相似文献   
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Synaptophysin is a protein involved in the biogenesis of synaptic vesicles and budding. It has been used as an important tool to investigate plastic effects on synaptic transmission. Nitric oxide (NO) can influence plastic changes in specific brain regions related to cognition and emotion. Experimental evidence suggests that NO and synaptophysin are co-localized in several brain regions and that NO may change synaptophysin expression. Therefore, the aim of the present work was to investigate if inhibition of NO formation would change synaptophysin mRNA expression in the hippocampal formation. Male Wistar rats received single or repeated (once a day for 4 days) i.p. injections of saline or l-nitro-arginine (l-NOARG, 40 mg/kg), a non-selective inhibitor of nitric oxide synthase (NOS). Twenty-four hours after the last injection the animals were sacrificed and their brains removed for ‘in situ’ hybridization study using 35S-labeled oligonucleotide probe complementary to synaptophysin mRNA. The results were analyzed by computerized densitometry. Acute administration of l-NOARG induced a significant (p < 0.05, ANOVA) increase in synaptophysin mRNA expression in the dentate gyrus, CA1 and CA3. The effect disappeared after repeated drug administration. No change was found in the striatum, cingulated cortex, substantia nigra or nucleus accumbens. These results reinforce the proposal that nitric oxide is involved in plastic events in the hippocampus.  相似文献   
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A simple, rapid mixed agglutination test using sheep erythrocytes (SRBC) sensitized with rabbit hemolysin and intact viable staphylococci is described for the detection of bound staphylococcal protein A. Soluble protein A was heat extracted from 50 clinical isolates as well as the Cowan I and Wood 46 strains of Staphylococcus aureus and titered by a hemagglutination test using sensitized SRBC and dilutions of soluble protein A. Protein A could be detected in all of these supernatants including that of S. aureus Wood 46, a strain generally considered to be protein A negative. These organisms were later retested by the mixed agglutination test and even those staphylococcal isolates expressing very low heat-extractable soluble protein A concentrations (1:2 titers) were positive, confirming the sensitivity of the test. In a screen of clinical isolates, only 4 of 235 (1.8%) coagulase-positive isolates were negative in the mixed agglutination test. Of 25 coagulase-negative isolates, none yielded a positive reaction.  相似文献   
54.
Steroid hormones regulate sexual behavior primarily by slow, genomically mediated effects. These effects are realized, in part, by enhancing the processing of relevant sensory stimuli, altering the synthesis, release, and/or receptors for neurotransmitters in integrative areas, and increasing the responsiveness of appropriate motor outputs. Dopamine has facilitative effects on sexual motivation, copulatory proficiency, and genital reflexes. Dopamine in the nigrostriatal tract influences motor activity; in the mesolimbic tract it activates numerous motivated behaviors, including copulation; in the medial preoptic area (MPOA) it controls genital reflexes, copulatory patterns, and specifically sexual motivation. Testosterone increases nitric oxide synthase in the MPOA; nitric oxide increases basal and female-stimulated dopamine release, which in turn facilitates copulation and genital reflexes. Serotonin (5-HT) is primarily inhibitory, although stimulation of 5-HT(2C) receptors increases erections and inhibits ejaculation, whereas stimulation of 5-HT(1A) receptors has the opposite effects: facilitation of ejaculation and, in some circumstances, inhibition of erection. 5-HT is released in the anterior lateral hypothalamus at the time of ejaculation. Microinjections of selective serotonin reuptake inhibitors there delay the onset of copulation and delay ejaculation after copulation begins. One means for this inhibition is a decrease in dopamine release in the mesolimbic tract.  相似文献   
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Zusammenfassung Der Mechanismus der Cytoprotektion von Prostaglandin (PG) auf die Magenmucosa ist unbekannt. Anaesthesierte Kaninchen erhielten in der Gruppe (GR) I (n=8) im. Aspirin (ASA) (100 mg/kg als Bolus, 66 mg/kg/h kontinuierlich) in der GR 11 (n=10) NaCI und in der GR III (n=7) zusätzlich zum ASA, PGE I (0,1 g/kg/min) als Infusion über 120 min. Der Mucosa-Blutfluß (MBF) wurde mit radioaktiven Mikrosphären gemessen. In der GR I fiel der MBF nach 15 min um 72,3+3,8% (+ SEM) und nach 120 min um 73,1+3,8% (p 0,05 gegen % Änderung in GR II und III). Nach 120 min zeigte sich in der GR I 19,8 + 7,6% der Fundusmucosa hämorrhagisch, in der GR 11 6,1 +5,2% und in der GR 1112,0+ 1,4% (p 0,05 gegen GR II und III). Wir schließen, daß der cytoprotektive Effekt des PGE I auf einer Aufhebung der ASA bedingten Mucosaischämie beruht.  相似文献   
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The US Food and Drug Administration approved a 6-month regimen of pretomanid, bedaquiline, and linezolid for extensively drug-resistant or multidrug-intolerant tuberculosis after a trial in South Africa demonstrated 90% effectiveness 6 months posttreatment. We report on a patient who completed the regimen using a lower linezolid dose.  相似文献   
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Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The...  相似文献   
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