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51.
Neuronal activities following olfactory bulb electrical stimulation were examined before and after administration of dopamine and dopamine antagonist in the rat olfactory tubercle. The inhibitory response to olfactory bulb stimulation was attenuated by systemic haloperidol administration, but the excitatory response to olfactory bulb stimulation rarely was modulated. Topical application of dopamine by iontophoresis extended the duration of inhibition in 56% of the neurons sampled and diminished it in 25%; the excitatory response was modulated in 42% of neurons, most of which were attenuated. These findings suggest that dopamine in the olfactory tubercle could be involved in modulations of neuronal activities related to olfactory transduction. 相似文献
52.
53.
Arianne C Lim Kitty WM Bloemenkamp Kees Boer Johannes J Duvekot Jan Jaap HM Erwich Tom HM Hasaart Pieter Hummel Ben WJ Mol Jos PM Offermans Charlotte M van Oirschot Job G Santema Hubertina CJ Scheepers Willem A Schöls Frank PHA Vandenbussche Maurice GAJ Wouters Hein W Bruinse 《BMC pregnancy and childbirth》2007,7(1):1-6
Background
Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.Methods
552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.Results
The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.Conclusion
Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy. 相似文献54.
H J Levine M J Wolk J F Keefe O H Bing J A Snow J V Messer 《The American journal of physiology》1977,232(5):H470-H477
The effect of iron-deficiency anemia on myocardial mechanics and energetics was studied in 10 anesthetized bealge puppies. Nine littermates served as controls. Left ventricular/body weight ratio was increased 14.2% (P less than 0.05) and cardiac index 36.5% (P less than 0.02) in the anemic puppies. Heart rate, mean systolic pressure, myocardial lactate extraction coefficient, and lactic dehydrogenase isozymes were similar in both groups. Contractile state measured in vivo (pressure-velocity curves) and in isolated muscles (isotonic force-velocity curves) was virtually identical in the littermate groups. Despite markedly increased coronary blood flow in the anemia animals, oxygen consumption per unit weight of myocardium was the same in both groups. Contractile element efficiency averaged 18.3% in 10 adult mongrel dogs studied in a similar fashion and was 27.1% and 39.8% in the normal puppies and anemic puppies, respectively. The oxygen cost of internal or force-generating work was similar among the three groups of dogs. It is concluded that the volume load produced by iron-deficiency anemia was associated with a normal contractile state, normal unit myocardial oxygen consumption, no evidence of chronic anaerobiosis, and a high contractile element efficiency, perhaps as a consequence of increased diastolic fiber stretch. 相似文献
55.
Seth M. Noar Richard Crosby Christina Benac Greg Snow Adewale Troutman 《AIDS and behavior》2011,15(5):1045-1057
The purpose of the current investigation was to apply the attitude-social influence-efficacy (ASE) model to achieve a theory-based understanding of condom use among low income, heterosexually active African-American STD clinic patients. N = 293 participants were recruited from a large, publicly-funded metropolitan STD clinic in the Southeastern United States and surveyed using an ACASI computer program. Results indicated that several ASE variables exhibited meaningful relationships with condom stages of change in univariate analyses, replicating patterns found in previous research. Fewer variables remained significant in multivariate analyses, however. There was also some support for the proposition that early stage movement (e.g., Precontemplation to Contemplation) is based more upon perceptions of condom use (e.g., pros, perceived norms), whereas later stage movement (e.g., Preparation to Action/Maintenance) is based more upon perceived and actual skills acquisition (e.g., condom self-efficacy, negotiation strategies). Results varied with regard to main and casual condom stage of change. Implications for developing tailored HIV prevention interventions with heterosexual African-Americans are discussed. 相似文献
56.
Andrea K. Knittel Rachel C. Snow Derek M. Griffith Jeffrey Morenoff 《AIDS and behavior》2013,17(8):2703-2714
In this study, we used data from Add Health Waves II and III to compare men who had been incarcerated to those who had not, and examined whether incarceration was associated with increased numbers of sexual partners and increased odds of concurrent partnerships. We used multivariate regression and propensity-score matching to compare sexual behavior of Wave III male respondents who had been incarcerated with those who had not, and compared sexual behavior at Wave II to identify differences in sexual behavior prior to incarceration. Incarceration was associated with an increased rate of lifetime sexual partnership, but this was attenuated by substance use. Criminal justice involvement was associated with increased odds of having partners who report concurrent partnerships, but no further increase was seen with incarceration. There were no significant sexual behavior differences prior to incarceration. These results suggest that the criminal justice system and substance use may interact to shape sexual behavior. 相似文献
57.
Xinle Cui Zhouhong Cao Goutam Sen Gouri Chattopadhyay Deborah H. Fuller James T. Fuller Dustin M. Snapper Andrew L. Snow James J. Mond Clifford M. Snapper 《Vaccine》2013
Infectious mononucleosis and B-cell transformation in response to infection with Epstein–Barr virus (EBV) is dependent upon binding of the EBV envelope glycoprotein gp350 to CD21 on B-cells. Gp350-specific antibody comprises most of the EBV neutralizing activity in the serum of infected patients, making this protein a promising target antigen for a prophylactic EBV vaccine. We describe a novel, tetrameric gp350-based vaccine that exhibits markedly enhanced immunogenicity relative to its monomeric counterpart. Plasmid DNA was constructed for synthesis, within transfected CHO cells, of a tetrameric, truncated (a.a. 1–470) gp350 protein (gp3501–470). Tetrameric gp3501–470 induced ∼20-fold higher serum titers of gp3501–470-specific IgG and >19-fold enhancements in neutralizing titers at the highest dose, and was >25-fold more immunogenic on a per-weight basis than monomeric gp3501–470. Further, epidermal immunization with plasmid DNA encoding gp3501–470 tetramer induced 8-fold higher serum titers of gp3501–470-specific IgG relative to monomer. Tetrameric gp3501–470 binding to human CD21 was >24-fold more efficient on a per-weight basis than monomer, but neither tetramer nor monomer mediated polyclonal human B-cell activation. Finally, the introduction of strong, universal tetanus toxoid (TT)-specific CD4+ T-cell epitopes into the tetrameric gp3501–470 had no effect on the gp3501–470-specific IgG response in naïve mice, and resulted in suppressed gp3501–470-specific IgG responses in TT-primed mice. Collectively, these data suggest that tetrameric gp3501–470 is a potentially promising candidate for testing as a prophylactic EBV vaccine, and that protein multimerization, using the approach described herein, is likely to be clinically relevant for enhancing the immunogenicity of other proteins of vaccine interest. 相似文献
58.
Background
Breathlessness causes significant burden in our community but the underlying socio-demographic and lifestyle factors that may influence it are not well quantified. This study aims to define these predictors of chronic breathlessness at a population level. 相似文献59.
PURPOSE OF REVIEW: The incidence and mortality of cardiovascular disease are increased in the context of rheumatoid arthritis. The purpose of this review is to examine our evolving understanding of the pathogenesis of cardiovascular disease in rheumatoid arthritis and to underscore the importance of tailored prevention of cardiovascular disease in this select population. RECENT FINDINGS: Recent reports have highlighted the shared pathobiology of cardiovascular disease and rheumatoid arthritis, both of which represent inflammatory disorders. Several reports have also provided much-needed insight into the deleterious impact that select therapies (including cyclo-oxygenase-2-specific inhibitors) may have in terms of the risk of cardiovascular disease in rheumatoid arthritis. Although further study is warranted, preliminary investigations also suggest that aggressive anti-inflammatory therapy, including the adjunctive use of statins, may play important cardioprotective roles in rheumatoid arthritis. SUMMARY: The pathogenesis of cardiovascular disease in rheumatoid arthritis is complex and involves several intermediate factors, including dyslipidemia, elevations in serum homocysteine, impaired insulin sensitivity, and endothelial dysfunction. Given the burden of cardiovascular disease in this population, it is important that health care providers caring for rheumatoid arthritis patients adopt a treatment course that is both comprehensive and individualized to address specific risk factors for cardiovascular disease. 相似文献
60.