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991.
A measles outbreak occurred among a highly vaccinated population in Alaska during 1998, providing an opportunity to determine the incremental efficacy of >or=2 doses of measles-containing vaccine (MCV) compared with 1 dose. Of 33 confirmed case patients identified, 31 had been vaccinated with 1 dose of MCV, 1 had received 2 doses, and vaccination status was unknown in 1 case. Seventy percent of cases were school-associated; 58% of cases occurred in 2 high schools. Of 3679 students attending the 2 schools, 50.4% and 45.5% had received >or=2 doses of MCV before measles introduction at the schools. The relative risk of developing measles among persons vaccinated with >or=2 doses of MCV compared with 1 dose was 0.06 (95% confidence interval, 0.01-0.44; P<.001), yielding an estimated incremental vaccine efficacy of 94.1% (95% confidence interval, 55.9%-99.2%; P<.001). Rapid implementation of a mandatory second-dose MCV requirement probably limited the extent of this outbreak.  相似文献   
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To eradicate measles in developing nations a vaccine capable of being administered at birth may be necessary. We immunized newborn rhesus macaques with naked DNA encoding the measles virus hemagglutinin, fusion and nucleoprotein genes. Prior to vaccination we passively transferred measles immunoglobulin to mimic maternal antibody. In the presence or absence of measles immunoglobulin, 23 of 25 infant macaques had detectable cell mediated immunity and 16 had protective levels of neutralizing antibody. The co-administration of an IL-2/IgG plasmid augmented the vaccine, increasing cell mediated immunity in all infants and increasing the antibody response in infants vaccinated without immunoglobulin. We show for the first time that DNA vaccination can protect a newborn primate from the high-level viremia that correlates with severe measles, even in the presence of maternal antibody. Further, the addition of a molecular IL-2 adjuvant augments this DNA vaccine.  相似文献   
996.
Emotional perception and neuroendocrine changes   总被引:1,自引:0,他引:1  
The present study was designed to investigate the neuroendocrine modifications during affective states. In particular, we investigate if the pleasantness of the stimuli has a different effect on neuroendocrine responses. To address this issue, we compared the effects of pleasant, neutral, and unpleasant pictures on catecholamine, adrenocorticotrophic hormone (ACTH), cortisol, and prolactin plasma levels. Ten male participants were submitted to three experimental sessions, each on one of the three experimental days, a week apart in a counterbalanced order. Although in the subjective arousal rating, pleasant (erotic pictures) and unpleasant stimuli (pictures of mutilated bodies) receive the same high score, a different neuroendocrine pattern was obtained: unpleasant stimuli elicited a decrease in prolactin concentration and increases in noradrenaline, cortisol, and ACTH levels, whereas pleasant slide set viewing induced an increase in prolactin levels. The results suggest that the neuroendocrine system responds selectively to affective motivationally relevant pictures.  相似文献   
997.
We report the case of a patient who, following a right thalamic haemorrhage, developed thalamic syndrome characterised by burning pain and hyperalgesia in the left side of the body. Three years later, following a further (contralateral ischaemic) stroke, she reported the complete disappearance of the pain and hyperalgesia. To our knowledge, this is the first described case of disappearance of thalamic syndrome following a second stroke, different in nature from and contralateral to the first. Various hypotheses, based on the nervous tracts and nuclei involved in pain processing, may be advanced to explain this occurrence.  相似文献   
998.
Tolcapone is a mixed (peripheral and central) catechol-O-methyltransferase (COMT) inhibitor, whereas entacapone is a preferential peripheral COMT inhibitor. Both drugs are able to decrease the peripheral conversion of L-DOPA into 3-O-methyl-DOPA and thereby increase plasma and cerebral levels of L-DOPA, the precursor of dopamine (DA). Tolcapone may also impair the extraneuronal catabolism of DA by inhibiting COMT activity in the brain. To evaluate the role played by peripheral and central COMT inhibition, we compared the effects of tolcapone and entacapone on COMT activity in peripheral tissues, and on striatal extracellular levels of L-DOPA and DA in rats. Tolcapone and entacapone, at the dose of 15 mg/kg p.o., were almost equally effective in inhibiting COMT activity in duodenum and liver. Tolcapone decreased striatal extracellular levels of homovanillic acid (HVA), thus confirming its central COMT inhibitory effect, whereas entacapone did not alter HVA efflux. Following L-DOPA/benserazide administration (50/15 mg/kg p.o.), both COMT inhibitors significantly increased striatal levels of L-DOPA and DA compared with saline. The levels of L-DOPA were similar after treatment with either COMT inhibitors, whereas the increase in DA output was significantly greater in rats given tolcapone compared to those given entacapone. We conclude that the blockade of central DA catabolism by tolcapone contributes to the greater increase in striatal DA levels achieved with this drug.  相似文献   
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1000.
Meta-analyses of short-term effect of air pollution use environmental exposure measurements defined as the concentration average between selected monitors. A simple quality index, Pearson's correlation coefficient between each pair of monitors, has been used in sensitivity analyses and meta-regression. To better characterize the degree of homogeneity in population exposure we propose to use Lin's concordance coefficient and the correlation coefficient between the difference and the average of each pair of values. Using simulated data and real data from the city of Rome (1998-2001) and Milan (1996-2002) we identify three conditions responsible of exposure misclassification when averaged concentrations are used in the analysis.  相似文献   
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