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121.
122.
Aims—To determine the extent of clonal cell contamination of peripheral blood progenitor cell (PBPC) collections in patients with multiple myeloma (MM) and to assess the purging efficacy of CD34 positive selection.  相似文献   
123.
Brief observations of mother-stimulated infant vocalizationwere perform ed during pediatric clinic visits on 4- to 6-month-oldinfants to determine whether mothers with positive attitudestoward the pregnancy and/or the in fant would have infants whovocalized more during clinic visits. Mothers with more positiveattitudes toward the pregnancy, assessed prenatally, had infantswho showed significantly more vocalization during clinic visitsat 5 months, 6 months, and the combination of 5 and 6 months.Mothers with more positive attitudes toward the infant had infantswho showed signcantly more vocalization at 4 months and thecombination of observations at 4 months and 6 months. Resultssuggest that brief observations of vocalization during clinicvisits may be useful as a rough index of the quality of themother-child interaction.  相似文献   
124.
Water-soluble shrimp allergens released during boiling (shrimp water) were characterized and compared to allergen extracts from boiled shrimp (shrimp meat). Both shrimp extracts contained acidic proteins (isoelectrofocusing) and demonstrated similar allergenic activity (RAST and RAST inhibition). Shrimp-water extract was analyzed further by immunoprinting with sera from 14 shrimp-sensitive, RAST-positive subjects, and six nonsensitive, RAST-negative individuals. Although none of the sera from shrimp-tolerant individuals reacted, 12/14 sera (85.7%) from shrimp-sensitive subjects reacted with shrimp-water proteins with acid isoelectric points. Shrimp-water extract was fractionated by chromatofocusing with pH and NaCl gradients. A number of eluted ultraviolet-absorbing peaks contained allergens as determined by RAST inhibition. Isoelectrofocusing demonstrated many protein bands present in these peaks, some of which bound IgE from a RAST-positive sera pool. These studies indicate that shrimp water is an excellent source of shrimp allergens, that chromatofocusing is a useful method for fractionation of shrimp allergens, and that shrimp allergens are generally protein molecules with acid isoelectric points.  相似文献   
125.
Spinal muscular atrophy (SMA) is, after Duchenne muscular dystrophy,the most common neuromuscular disorder in childhood. The generesponsible for childhood SMA has been mapped to the q11. 2– q13. 3 region of chromosome 5. We have extended ourlinkage studies of SMA In the French - Canadian population toInclude microsatellite markers at the D5S125, D5S351, D5S435,JK53CA1/ 2 and MAPI B locl. These markers span about 4 cM ofthe SMA candidate region. We observed significant evidence forlinkage between SMA and all the markers tested. The analysisof recombinant chromosomes provide evidence for the followinggenetic order: D5S125-D5S435-MAP1B-3'-JK53CA1/2 and places D5S351proximal to JK53CA1/2. Furthermore, we confirm the current localizationof the SMA gene distal to D5S435. Finally, we provide demonstrationof significant linkage disequilibrium between childhood-onsetSMA and four of the five marker loci, D5S125, D5S435, D5S351and JK53CA1/2. Analysis of SMA-region haplotypes suggests thatthere may be a predominant SMA allele that is present on about17% of SMA chromosomes in this sample of the French - Canadianpopulation. We conclude that the observed linkage disequilibriumis likely due to genetic drift among regions of Quebec, consistentwith this population's early history.  相似文献   
126.
Binding of human and rat CD59 to the terminal complement complexes.   总被引:1,自引:1,他引:1       下载免费PDF全文
T Lehto  B P Morgan    S Meri 《Immunology》1997,90(1):121-128
CD59-antigen (protectin) is a widely distributed glycolipid-anchored inhibitor of complement lysis. CD59 interacts with complement components C8 and C9 during assembly of the membrane attack complex (MAC). To evaluate species specificity of these interactions we have in the present study examined cross-species binding of isolated human and rat CD59 to the terminal complement components C8 and C9. By using primarily soluble CD59 isolated from urine (CD59U) potentially non-specific binding interactions of the phospholipid portion of the membrane forms of CD59 could be avoided. Sucrose density gradient ultracentrifugation analysis showed that human CD59U bound to both human and rat C8 in the SC5b-8 complexes. Similar binding occurred when rat CD59U was used. The degree of binding did not significantly differ between the heterologous and homologous CD59-C8 combinations. C9 from both species inhibited the binding of CD59 to soluble SC5b-8. In ligand blotting analysis human and rat CD59U bound to human and rat C8 alpha gamma-subunit and C9. Binding of human and rat CD59U was stronger to human than rat C9. In plate binding assays the erythrocyte form of CD59 (CD59E) bound to both human and rat C8. Binding of CD59E to heterologous C9 was considerably weaker than to homologous C9. Our results imply that the reciprocal binding sites between C8 and CD59 and to a lesser degree between CD59 and C9 are conserved between human and rat. Interactions of CD59 with the terminal C components are thus species selective but not 'homologously restricted'.  相似文献   
127.
The complete amino acid sequence of the nucleic acid binding protein p10 of the Rickard strain of feline leukemia virus (FeLV) has been determined. Fragments obtained by enzymatic digestion were purified by reverse-phase liquid chromatography and subjected to semiautomated Edman degradation. FeLV p10 is a basic polypeptide composed of 57 amino acids with Mr = 6604. The structure of p10 is compared to the structures of other retroviral nucleic acid binding proteins, and an analysis of a highly conserved region, the putative binding domain, is presented.  相似文献   
128.
Apart from a small number of reports from people who are based in hospitals, data on viral load in HIV-infected people in sub-Saharan Africa, where most infections occur, are lacking. We report serum HIV-1 RNA levels in a population-based cohort in rural Uganda using the nucleic acid sequence-based amplification procedure (NASBA) test kit and describe their relation to CD4 counts and World Health Organization (WHO) clinical staging. The median (interquartile range [IQR]) viral loads were 87,000 copies/ml (37,500-295,000 copies/ml) in 40 prevalent cases infected for >6 years, and 31,000 copies/ml (7800-174,000 copies/ml) in 65 incident cases with seroconversion dates within the previous 6 years. Although we found a correlation between viral load and absolute CD4 count (p < .0001), there was no evidence for an association with CD4 decline (p = .1). Overall, there was a significant trend of increasing viral load with worsening clinical stage from a median viral load of 15,000 for those in WHO stage 1 (asymptomatic) to 150,600 copies/ml for those in stage 4 (AIDS; p < .001). However, the association was seen only in incident cases. Thus, we found that the NASBA test on serum was a useful indicator of disease stage especially in persons known to be infected for <6 years. Such baseline data are important for vaccine research, and if antiretroviral drugs become available to more than a few people in Africa, it will be important that accurate viral load estimations are available at least in a proportion of people to monitor the effectiveness of treatment, and measure the compliance and emerging resistance to these drugs.  相似文献   
129.
Manganese (Mn) is a trace nutrient necessary for life but becomes neurotoxic at high concentrations in the brain. The brain is a “privileged” organ that is separated from systemic blood circulation mainly by two barriers. Endothelial cells within the brain form tight junctions and act as the blood–brain barrier (BBB), which physically separates circulating blood from the brain parenchyma. Between the blood and the cerebrospinal fluid (CSF) is the choroid plexus (CP), which is a tissue that acts as the blood–CSF barrier (BCB). Pharmaceuticals, proteins, and metals in the systemic circulation are unable to reach the brain and spinal cord unless transported through either of the two brain barriers. The BBB and the BCB consist of tightly connected cells that fulfill the critical role of neuroprotection and control the exchange of materials between the brain environment and blood circulation. Many recent publications provide insights into Mn transport in vivo or in cell models. In this review, we will focus on the current research regarding Mn metabolism in the brain and discuss the potential roles of the BBB and BCB in maintaining brain Mn homeostasis.  相似文献   
130.
Background

Cardiovascular disease (CVD) risks are of concern among immigrants and refugees settling in affluent host countries. The prevalence of CVD and risk factors among Somali African immigrants to the U.S. has not been systematically studied.

Methods

In 2015–2016, we surveyed 1156 adult Somalis in a Midwestern metropolitan area using respondent-driven sampling to obtain anthropometric, interview, and laboratory data about CVD and associated risk factors, demographics, and social factors.

Results

The prevalence of diabetes and low physical activity among men and women was high. Overweight, obesity, and dyslipidemia were also particularly prevalent. Levels of calculated CVD risk across the community were greater for men than women.

Conclusion

Though CVD risk is lower among Somalis than the general U.S. population, our results suggest significant prevalence of risk factors among Somali immigrants. Comparison with prior research suggests that CVD risks may be increasing, necessitating thoughtful intervention to prevent adverse population outcomes.

  相似文献   
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