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41.
Given the failure to find a definitive cure for COVID-19,the only hopes for controlling the pandemic right now are vaccine production and universal vaccination.Therefore,vaccine is vital to the prevention and control of COVID-19 outbreak and it will support global health security.  相似文献   
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Aims/hypothesis  

The aim of the study was to analyse the insulin requirements of women with type 1 diabetes mellitus throughout pregnancy.  相似文献   
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HIV-1 enters the brain at the early stage of infection and resides primarily in a limited number of macrophages/microglia and astrocytes. Infection of these cells, however, may not explain the massive neuronal pathology which is seen in AIDS-associated dementia, suggesting a role for factors released from HIV-1 infected cells that trigger a cascade of events leading to neurodegeneration. Our results indicate that Tat, the potent regulatory protein of HIV-1 which is secreted by infected cells and can affect neighboring uninfected cells by transcellular means, can influence multiple biological events that lead to neuronal injury. These findings demonstrate that treatment of neuronal cells with Tat affects MAPK/ERK1/2 activity, the downstream central component of the nerve growth factor (NGF) signaling pathway. Furthermore, our data indicate that treatment of cells with Tat severely decreases expression of p35, a neuron-specific activator of cdk5, a cyclin dependent kinase that phosphorylates several neuronal proteins including neurofilament, and plays an important role in neuronal differentiation and survival. In parallel, Tat can bind to the cellular protein, Puralpha, which associates with cdk5. Further, results from Puralpha knockout animals revealed a decrease in p35 activity, pointing to the importance of Puralpha association with cdk5 in the activity of cdk5:p35 complex. These data demonstrate the cooperativity between HIV-1 Tat and the Puralpha in deregulation of the NGF signal transduction pathway in neuronal cells.  相似文献   
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This prospective study was designed to perform lamellar body count of amniotic fluid to evaluate fetal lung maturity. Lamellar body counts of 80 amniotic fluid samples from 80 pregnant women (28-40 weeks of gestation) were evaluated. After delivery, each infant was evaluated for any evidence of respiratory distress syndrome. Standard clinical and radiographic criteria were used to diagnose respiratory distress syndrome, and the diagnosis was confirmed by reviewing newborn records. Twenty (25%) infants delivered within 24 hours of sample collection developed RDS. Lamellar body count more than 50,000/microl predicted pulmonary maturity. Seventeen out of 20 respiratory distress syndrome cases had been predicted correctly. The negative predictive value of lamellar body count>50,000/microl was 93% and positive predictive value was 48% and the sensitivity for prediction of RDS was 85% and specificity was 70%. Lamellar body count can be used as a favourable predictor of fetal lung maturity because it is quick, simple and universally available. Also it can be used as an extremely inexpensive, reliable screening test for evaluating fetal lung maturity.  相似文献   
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Seventy-four delinquent drug abusing adolescents were randomly assigned to inpatient or outpatient treatment. One year results on several measures of social functioning as well as MMPI scores are analyzed. At one year, no significant differences in outcome are noted on these measures. Implications of these findings are discussed as well as possible changes which may occur at a subsequent, two year, follow-up.  相似文献   
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Most drugs of abuse increase dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) release in the shell of the nucleus accumbens. The effects of ascorbate, which is known to modulate dopamine neurotransmission, on the extracellular level of DOPAC in the nucleus accumbens of naive rats and of rats treated acutely with morphine were studied by using in vivo microdialysis and high performance liquid chromatography with electrochemical detection (HPLC-ECD). Acute morphine (20 mg/kg ip) treatment increased the level of DOPAC in the nucleus accumbens to approximately 170% of basal level. Acute treatment with ascorbate (500 mg/kg ip) alone did not alter nucleus accumbens' DOPAC level, but pretreatment with ascorbate (500 mg/kg ip) 30 min before morphine administration attenuated the effects of acute morphine on the level of DOPAC. These results suggest that ascorbate modulates the mesolimbic dopaminergic pathway.  相似文献   
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OBJECTIVE: The purpose of this study was to determine whether there is a difference in body composition and the factors that are associated with fat mass in the large-for-gestational-age infants of women with gestational diabetes mellitus compared with the large-for-gestational-age infants of women with normal glucose tolerance levels. STUDY DESIGN: Large for gestational age was defined as weight >90th percentile for gestational age, race, and sex on the basis of our population's normative data. Anthropometric measurements and/or total body electrical conductivity estimated body composition that included fat mass, percent body fat, and lean body mass were obtained. Multiple stepwise regression was used to determine factors correlating with fat mass. RESULTS: Fifty cases of women with gestational diabetes mellitus and 52 cases of women with normal glucose tolerance levels were evaluated. Infants of mothers with gestational diabetes mellitus had increased fat mass (662 vs 563 g; P = .02) and percent body fat (16.2% vs 13.5%; P = .002) but decreased lean body mass (3400 vs 3557 g; P = .0009), as compared with infants of mothers with normal glucose tolerance levels, despite similar birth weights. Stepwise regression on all 102 women showed gestational age and a diagnosis of gestational diabetes mellitus correlated with fat mass (r2 = 0.11; P = .001). For gestational diabetes mellitus alone, both gestational age and fasting value of the oral glucose tolerance test correlated with fat mass and percent body fat (r2 = 0.33 [P = .0009] and r2 = 0.26 [P = .005], respectively). CONCLUSION: Large-for-gestational-age infants of mothers with gestational diabetes mellitus have increased fat mass and decreased lean body mass compared with infants of mothers with normal glucose tolerance levels. In gestational diabetes mellitus, gestational age and fasting value of the oral glucose tolerance test correlated best with fat mass.  相似文献   
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