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131.
Specific and nonspecific immune factors in dental plaque fluid and saliva from young and old populations. 总被引:6,自引:11,他引:6 下载免费PDF全文
M F Cole S D Hsu B J Baum W H Bowen L I Sierra M Aquirre G Gillespie 《Infection and immunity》1981,31(3):998-1002
Separate samples of supragingival dental plaque overtly free of blood were centrifuged to obtain the free fluid phase (plaque fluid). Bound protein was eluted from the plaque bacteria and matrix by washing the plaque with a low-pH buffer. The plaque fluid, low pH eluate, and whole saliva were assayed for immunoglobulins A, G, and M, the third component of complement, lysozyme, lactoferrin, and lactoperoxidase. Concentrations of total protein and albumin were also determined. Antibody reactive with specific plaque bacteria was detected by indirect immunofluorescent microscopy. Specific and nonspecific immune proteins were present in plaque fluid from adult subjects at significantly greater concentrations than in their saliva, which suggests that these proteins are concentrated in dental plaque. The results indicate that both saliva and gingival exudate contribute to the immunological proteins found in the free fluid phase of dental plaque. The observation that immunoglobulin A antibody reactive with plaque bacteria could be detected in plaque fluid suggests that a wide variety of immunological reactions may occur in the dental plaque. These potential interactions between host, plaque bacteria, and their products could serve to influence the plaque flora and its ability to induce disease. 相似文献
132.
API0134对大鼠血浆和血小板血栓素B2生成与血小板聚集的影响 总被引:2,自引:0,他引:2
用放射免疫分析法和比浊法测定PAI0134对大鼠血浆血栓素B2浓度,血小板TXB2生成血小板聚集的影响。静脉注射API013470mg或100mg.kg显著降低血浆TXB2浓度,其降低2率分别为38.8%和51.6%,API0134明显抑制ADP诱导的大鼠血小板聚集和TXB2生成,抑制率分别为27.8%,39.5%,和41.4%,53.6%,两抑制率间呈显著正相关。 相似文献
133.
Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women 总被引:4,自引:0,他引:4
Tworoger SS Yasui Y Vitiello MV Schwartz RS Ulrich CM Aiello EJ Irwin ML Bowen D Potter JD McTiernan A 《Sleep》2003,26(7):830-836
STUDY OBJECTIVES: To examine the effects of a moderate-intensity exercise or stretching intervention and changes in fitness, body mass index, or time spent outdoors on self-reported sleep quality and to examine the relationship between the amount and timing of exercise and sleep quality. DESIGN: A randomized intervention trial. SETTING: A cancer research center in Seattle, Washington. PARTICIPANTS: Postmenopausal, overweight or obese, sedentary women not taking hormone replacement therapy, aged 50 to 75 years, and recruited from the Seattle metropolitan area. INTERVENTIONS: A yearlong moderate-intensity exercise (n=87) and a low-intensity stretching (n=86) program. MEASUREMENTS AND RESULTS: Among morning exercisers, those who exercised at least 225 minutes per week had less trouble falling asleep (odds ratio [OR]: 0.3, P < or = .05) compared with those who exercised less than 180 minutes per week. However, among evening exercisers, those who exercised at least 225 minutes per week had more trouble falling asleep (OR: 3.3, P < or = .05) compared to those who exercised less than 180 minutes per week. Stretchers were less likely to use sleep medication (OR = 0.4, P < or = .05) and have trouble falling asleep (OR: 0.7, P < or = .10) during the intervention period compared with baseline. A greater than 10% versus a 1% or less increase in maximum O2 consumption over the year was associated with longer sleep duration (P < or = .05), less frequently falling asleep during quiet activities (P < or = .05), and less use of sleep medication (P < or = .05). Reductions in body mass index and increases in time spent outdoors had inconsistent effects on sleep quality. CONCLUSIONS: Both stretching and exercise interventions may improve sleep quality in sedentary, overweight, postmenopausal women. Increased fitness was associated with improvements in sleep. However, the effect of moderate-intensity exercise may depend on the amount of exercise and time of day it is performed. 相似文献
134.
135.
酵母双杂合系统AD端阴离子交换蛋白C-末端表达质粒的构建 总被引:2,自引:0,他引:2
利用PCR方法,从阴离子交换蛋白1(AE1)全长cDNA中扩增出约350bp c末端cDNA片段,测序后将其克隆至pGADT7载体上,用醋酸锂法构建好的pADT7-AE1-c末端转染酵母菌HA109,观察其在选择性培养基上的表达情况。结果表明,获得了530bp AE1c-末端cDNA,pGADT7-AE1-c末端对酵母无毒性,不能激活检测基因,可作为酵母双杂合系统中的靶基因。 相似文献
136.
Many residues involved in polymorphic antibody-binding epitopes on class II molecules are located on the -helix of DRβ chains. Although they have received less attention, residues in the peptide-binding groove and second domain of the DRβ chain may also be critical for polymorphic anti-DR antibody epitopes. In this study, we used transfectants expressing site-directed mutations at positions in the HLA-DR β1 and β2 domains and flow cytometry to define the epitopes of several polymorphic anti-DR antibodies. Both DR(β 1*0403) residues 14 and 25 were shown to be involved in the epitopes of mAbs DA6. 164, HU-20, Q5/6, and 50D6, and DR(β 1*0701) residue 14 was shown to be critical for the epitopes of two DR7-specific mAbs, SFR16-DR7M and TAL 13. 1. Unlike most other residues shown to be important in antibody-binding epitopes, residue 14 is located in the floor of the peptide-binding groove and residue 25 is in an outer loop, each with their side chains pointing down, such that antibodies may directly contact these residues from below the binding groove. Two residues in the β2 domain, β180 and β181, were also shown to be involved in the epitopes of three polymorphic anti-DR mAbs, NFLD.D1, NFLD.M1, and LY9. Although these two residues are close to the transmembrane domain in the linear sequence, their solvent accessibility in the DR1 structures is quite impressive. Our data provide new evidence that residues accessible under the peptidebinding groove contribute to polymorphic antibody-binding epitopes. 相似文献
137.
X T Fu E Klohe C Alber W Y Yu G B Ferrara M P Pistillo M Ballas R W Karr 《Human immunology》1992,33(3):193-201
In a previous study, we used transfectants expressing hybrid HLA-DR(beta 1*0403)/DR(beta 1*0701) chains to map sequences involved in polymorphic antibody binding epitopes on DR(alpha, beta 1*0403) or DR(alpha, beta 1*0701) molecules. Amino acids 1-40 of the beta 1 domain were found to make the major contributions to most of the antibody binding epitopes studied. To begin to localize sequences that contribute to polymorphic antibody epitopes on DR(alpha,beta 1*0101), DR(alpha,beta 1*1101) and DR(alpha,beta 3*0202) molecules, we used indirect immunofluorescence and flow cytometry to assess the binding of mAb to transfectants expressing hybrid DR(beta 1*0101)/DR(beta 1*1101) or DR(beta 1*1101)/DR(beta 3*0202) chains that divide the DR beta chain into three segments: amino acids 1-40, 41-97, and the beta 2 domain. The results indicate that amino acids 41-97 of the beta 1 domain on DR(beta 1*0101), DR(beta 1*1101), or DR(beta 3*0202) are critical in most of the epitopes, including those recognized by human antibodies MP4 and MP12, and mouse mAb GS88.2, I-LR1, 21r5, and 7.3.19.1, whereas amino acids 1-40 of DR(beta 1*1101) are critical in the epitope recognized by the MCS-7 mAb, and both segments 1-40 and 41-97 of DR(beta 1*1101) are important in the epitopes recognized by the I-LR2 and UL-52 mAbs. Based on these data and comparison of DR beta allelic protein sequences, the residues that may play critical roles in these antibody binding epitopes are predicted. 相似文献
138.
A behavioral approach to increasing calorie consumption in children with cystic fibrosis 总被引:1,自引:1,他引:1
To increase calorie consumption of 5 mildly malnourished children with cystic fibrosis (CF), intervention was implemented in multiple baseline fashion across snack and three meals. Intervention involved nutritional education establishing gradually increasing calories goals, teaching parents contingency management strategies, and a reward system for achieving calorie goals. Following 6 treatment sessions, the children's calorie intake increased across meals and total calorie intake was 25 to 43% above baseline. The calorie increase was maintained at 9-month follow-up. Significant changes in weight and height were made during treatment and the year following intervention. The results suggest that the long-term oral intake of children with CF can be modified by a short-term behavioral intervention. 相似文献
139.
不同剂量病毒唑治疗肾综合征出血热306例疗效分析 总被引:3,自引:0,他引:3
应用不同剂量病毒唑对306例肾综合征同血热患者进行治疗对比观察,发现两治疗组疗效无显著性差异,但两治疗组怀对照组相比,越期率高,肾功能恢复快,血小板数恢复早,病程缩短,并发症减少,病死率也有所下降,但无显著性差异。 相似文献
140.