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101.
应用双向电泳技术初步建立人精子头部蛋白质图谱 总被引:10,自引:3,他引:7
目的 :利用人类精子蛋白质组分析的双向蛋白电泳 (2 DE)技术建立正常人精子头部蛋白质图谱。 方法 :先用固相pH梯度 SDS电泳技术 (IPG DALT)对全精子和精子头部蛋白质抽提物进行蛋白质分离 ,然后用图像分析软件比较精子头部蛋白质图像与精子蛋白质图像的蛋白质斑点组成差异。其中 ,全精子蛋白质的抽提比较了硫脲 /尿素 /盐酸胍和Kit/盐酸胍两种抽提方法。 结果 :硫脲 /尿素 /盐酸胍法与Kit/盐酸胍法所得的全精子 2 DE图像蛋白质斑点分别为 80 2个和 797个 ,其中相同的有 4 92个 ,将两种方法获得的图像整合而得到的全精子蛋白质图像有1 1 0 7个蛋白质斑点 ;精子头部图像蛋白质斑点有 4 2 8个 ,经匹配 ,全部来源于全精子蛋白质图像。 结论 :综合采用两种蛋白质提取方法初步建立了精子头部蛋白质图谱。 相似文献
102.
Judith A. Disney Richard C. Graves John W. Stamm Harry M. Bohannan James R. Abernathy 《Community dentistry and oral epidemiology》1989,17(3):139-143
This paper presents the comparative effectiveness of fluoride mouthrinse (FMR) on high and low caries forming children after a 4-yr exposure to weekly rinse beginning in the first grade. Over 1200 grade 1 children drawn from both fluoride deficient and fluoridated sites were divided into treatment and concurrent, longitudinal control groups. After 4 yr these children were stratified according to caries increment; those above the 75th percentile were considered high caries formers, all others were designated low caries formers. After adjustment of the mean increments for differences in SES, age, race, and sex in rinse and control groups, high caries formers (approximately 25% of the children) in the rinse and control groups in fluoride deficient areas showed increments of 7.00 and 7.79 surfaces, respectively, indicating a savings of 0.79 surfaces. Low caries formers (approximately 75% of the children) demonstrated increments of 1.11 DMFS in the rinse group and 1.40 in the control group (savings 0.29 DMFS). The pattern was quite similar for children in fluoridated areas except that the increments, as well as the savings realized, were lower. The results raise questions as to the practical effectiveness of school based FMR programs even for high caries forming children. 相似文献
103.
ABSTRACT: The ability to identify groups of children at risk of initiating a smoking habit may prove useful in developing effective smoking prevention programs. This report includes data collected over a three-year period, and attempts to predict adolescents' smoking behavior using both cross-sectional and longitudinal analyses. In addition, predictor variables reflecting both interpersonal and intrapersonal domains were included. Results indicated the highest rates of accurate classification into smoking categories were achieved with cross-sectional analyses. In addition, interpersonal variables emerged as most important in all analyses. Implications for smoking prevention programming are discussed. 相似文献
104.
105.
The University of North Carolina Caries Risk Assessment Study I: Rationale and Content 总被引:1,自引:0,他引:1
John W. Stamm DDS DDPH MScD Judith A. Disney DMD MPH Richard C. Graves DDS DrPH Harry M. Bohannan DMD MSD James R. Abernathy PhD 《Journal of public health dentistry》1988,48(4):225-232
This article presents the rationale and content of a current study that seeks to improve methods to identify children at high risk to dental caries. It summarizes the results of the development of a 12-factor, preliminary caries prediction model based on data derived from the National Preventive Demonstration Program. Despite data limitations, the model produced a sensitivity of .5 and specificity of .8 for four-year caries increment prediction in first- and fifth-grade children. Data on a number of additional potential predictors are being collected in two sites to expand and improve the existing model. These factors are identified. 相似文献
106.
Written Simulation of Patient-Doctor Encounters. 1. Research Instrument for Registration of the Performance of General Practitioners 总被引:3,自引:0,他引:3
A written simulation of patient-doctor encounters is described,involving five patients with vague complaints, an instructionpatient with sinusitis and a test patient withacute appendicitis. Nineteen general practitioners were confrontedwith it. The extent to which the simulation distorted realityand the implications of such distortions were considered inan attempt to assess the content validity. The conclusion wasthat the simulation gave a realistic impression of the generalpractitioners' diagnostic and therapeutic approach to patientswith vague complaints. The searching procedures in relationto the complaint and the patient's perception of the complaintwere adequately depicted, and the therapeutic procedures approximatedclosely to reality. There was some distortion in the attentionpaid to psychosocial aspects as these were given more attentionin the simulation than they receive in reality. 相似文献
107.
Three cases of unusual corrugated mucosal pattern in the esophagus accompanying the typical motility disturbance of progressive systemic sclerosis (PSS) are reported. The changes were rarely seen in a group of patients with esophageal involvement by PSS. 相似文献
108.
M. R. DAHA L. A. VAN ES H. M. HAZEVOET A. KIJLSTRA 《Scandinavian journal of immunology》1982,16(2):117-122
The capacity of human peripheral monocytes to degrade soluble immunoglobulin (IgG) aggregates (AIgG) was studied in vitro. Under serum-free conditions peripheral monocytes from normal donors were able to degrade soluble AIgG in a linear and time-dependent fashion. Addition of fresh human or fresh guinea-pig serum to the incubation mixtures caused a marked increase in degradation of the amount of soluble AIgG available. The stimulatory effect of fresh serum was complement-mediated, because it was abolished by heat treatment of the serum and was not seen when C4- or C3-deficient sera were tested. Functional inactivation of C3 receptors on the phagocytes by trypsin also abolished the complement-mediated stimulation, suggesting cooperation between Fc and C3 receptor in degradation of soluble AIgG. No significant differences were found between monocytes from normal donors and those from patients with systemic lupus erythematosus, as far as degradation is concerned in the presence of complement. 相似文献
109.
110.