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1.
目的利用红外光谱法测定延安大学附属医院泌尿外科手术获得的泌尿系结石成分,探讨延安地区泌尿系结石成分与年龄、性别等关系,比较上、下尿路结石成分特点,分析延安地区泌尿系结石发生的流行病学情况,为临床制定有效的个体化治疗及预防措施提供参考依据。方法收集2013年1月至2017年1月在延安大学附属医院泌尿外科治疗1984例尿路结石患者的年龄、性别、结石部位等临床资料,对比分析延安地区泌尿系结石在不同年龄、不同性别、不同解剖部位的分布特点。结果在1984例泌尿系结石的患者中,按每10岁年龄大小分组排序,统计各年龄阶段泌尿系结石发病情况,男性患者有1346例,女性患者有638例,男性年龄(50.23±14.48)岁,女性年龄(47.87±14.51)岁,男、女患者比例约2.11∶1。在66~75岁年龄段,尿路结石发病率性别差异具有统计学意义(P<0.05)。结石成分以混合性结石为主,以混合性结石为主,共1582例,占79.76%。其中1665例(83.92%)为上尿路结石,上、下尿路结石的比例为5.22∶1,其余为肾结石合并膀胱结石。上尿路结石中男性1062例,女性603例,男女比例为1.76∶1;下尿路结石中男性284例,女性35例,男女比例为8.11∶1。青壮年(年龄≤45岁)泌尿系结石患者草酸钙为主结石、感染性结石多见;中老年(年龄>45岁)泌尿系结石者草酸钙为主结石、尿酸类结石多见。感染性结石患者性别差异具有统计学意义(P<0.05)。结论在延安地区男性较女性更容易患泌尿系结石。同时,不同年龄段结石构成成分具有差异。对于年龄≤45岁患者,主要以草酸钙为主结石、感染性结石多见,这与结石整体发病率基本一致;而对于年龄>45岁患者,主要以草酸钙为主结石、尿酸性结石多见。表明对于不同年龄段的结石患者,可以根据上述结果在结石的预防和治疗上综合考量,给予明确而更加合理的治疗。  相似文献   
2.
An important task of vision is the segregation of figure and ground in situations of spatial occlusion. Psychophysical evidence suggests that the depth order at contours is defined early in visual processing. We have analysed this process in the visual cortex of the alert monkey. The animals were trained on a visual fixation task which reinforced foveal viewing. During periods of active visual fixation, we recorded the responses of single neurons in striate and prestriate cortex (areas V1, V2, and V3/V3A). The stimuli mimicked situations of spatial occlusion, usually a uniform light (or dark) rectangle overlaying a grating texture of opposite contrast. The direction of figure and ground at the borders of these rectangles was defined by the direction of the terminating grating lines (occlusion cues). Neuronal responses were analysed with respect to figure-ground direction and contrast polarity at such contours. Striate neurons often failed to respond to such stimuli, or were selective for contrast polarity; others were non-selective. Some neurons preferred a certain combination of figure-ground direction and contrast polarity. These neurons were rare both in striate and prestriate cortex. The majority of neurons signalled figure-ground direction independent of contrast polarity. These neurons were only found in prestriate cortex. We explain these responses in terms of a model which also explains neuronal signals of illusory contours. These results suggest that occlusion cues are used at an early level of processing to segregate figure and ground at contours.  相似文献   
3.
A sample enriched for familial combined hyperlipidemia (FCHL) was examined for evidence of an association between genotype at an apolipoprotein B (apoB) elevating locus defined by complex segregation analysis and FCHL. Complex segregation analysis detected a locus with a large effect on plasma apoB levels and was used to compute the most probable genotype of family members. None of the 35 normolipidemic adults carried a copy of the allele associated with elevated apoB levels, yet 58% of the 109 adults with FCHL carried 1 (29%) or 2 (28%) copies. Two of 28 (7%) normal children had 1 copy of this allele and none had 2 copies, while 88 of 182 (48%) children with FCHL had 1 (26%) or 2 (22%) copies. Further, 4l of 48 (85%) individuals classified as having hyperapobetalipoproteinemia did not carry a copy of this “elevated apoB” allele. Therefore, the presence of the allele associated with elevation of apoB level is highly predictive of FCHL and this association cannot be explained solely by the presence of elevated apoB levels in FCHL, suggesting that the locus controlling apoB levels may play an etiologic role in FCHL. © 1993 Wiley-Liss, Inc.  相似文献   
4.
Segregation analysis of discrete traits can be conducted by the classical mixed model and the recently introduced regressive models. The mixed model assumes an underlying liability to the disease, to which a major gene, a multifactorial component, and random environment contribute independently. Affected persons have a liability exceeding a threshold. The regressive logistic models assume that the logarithm of the odds of being affected is a linear function of major genotype effects, the phenotypes of older relatives, and other covariates. A formulation of the regressive models, based on an underlying liability model, has been recently proposed. The regression coefficients on antecedents are expressed in terms of the relevant familial correlations and a one-to-one correspondence with the parameters of the mixed model can thus be established. Computer simulations are conducted to evaluate the fit of the two formulations of the regressive models to the mixed model on nuclear families. The two forms of the class D regressive model provide a good fit to a generated mixed model, in terms of both hypothesis testing and parameter estimation. The simpler class A regressive model, which assumes that the outcomes of children depend solely on the outcomes of parents, is not robust against a sib-sib correlation exceeding that specified by the model, emphasizing testing class A against class D. The studies reported here show that if the true state of nature is that described by the mixed model, then a regressive model will do just as well. Moreover, the regressive models, allowing for more patterns of family dependence, provide a flexible framework to understand gene-environment interactions in complex diseases.  相似文献   
5.
成分输血在临床中的应用   总被引:7,自引:0,他引:7  
颜景欣 《医学综述》2006,12(24):1533-1535
成分输血是现代输血学的重要标志之一。临床医生要了解成分输血的知识,遵循科学用血、合理用血、节约用血的原则,根据病情有针对性地开展成分输血。成分输血的重点,应当是血液的有形成分,即以红细胞和血小板为主的成分输血。本文就成分输血的特点与临床应用等有关问题进行综述。  相似文献   
6.
Methylation is an important pathway in the biotransformation of many drugs, neurotransmitters, and xenobiotic compounds. Histamine N-methyltransferase (HNMT) catalyzes the Nτ-methylation of histamine and structurally related compounds. Measurement of HNMT activity in the RBC makes it possible to access variation in the enzyme activity that may reflect differences in less accessible tissues such as brain. Previously reported high family correlations for RBC HNMT activity suggested that genetic inheritance plays a major role in the regulation of variation in this enzyme. In the present study we completed complex segregation analyses of RBC HNMT activity of 241 individuals in 51 nuclear families that were randomly ascertained through children in the Rochester, Minnesota public school system in order to characterize the mode of inheritance of this important enzyme. We found evidence for major gene influence on the regulation of RBC HNMT activity. Both transformed and untransformed data support the presence of Mendelian major gene segregation, but the gene frequency differences do not indicate a direct correspondence between genotypes inferred from the two sets of analyses. Analyses of the skewed untransformed data indicated the presence of a relatively rare (Q = 0.121) additive major gene for high activity, with the three overlapping genotype distributions representing 77, 21, and 2 % of individuals. Analyses of the normalized transformed data indicated the presence of a common (Q = 0.71) additive major gene for high activity, with the three overlapping genotype distributions accounting for 9, 41, and 50 % of individuals. The analyses of transformed data give the best fit as well as the most parsimonious Mendelian major gene model. However, we cannot rule out the possibility of multiple alleles, and analyses of untransformed data provide some support for a third allele. Molecular studies will be needed to validate and characterize the alleles that regulate RBC HNMT activity levels in humans. © 1993 Wiley-Liss. Inc.  相似文献   
7.
自行设计和制造平面和三维立体培养室及贮液室等构件,用医用硅胶管连接;转子泵作为动力源,贮液室通气口供给5%CO2 95%空气,恒温水浴箱保持构件37℃恒温,这样组成了种植细胞与生物瓣支架复合体的脉动培养系统,并进行生物力学和生物相容性测试,为心脏组织工程瓣的体外构建提供研究器材。结果显示,该装置密闭性能好,内环境能保持37±1℃、CO2浓度5%±1%、pH值6.8~7.5;流量在0.125~6.0L/min的范围内任意调节;同种瓣膜上的内皮细胞经2周培养后扩增约10倍;瓣膜支架的细菌和霉菌培养均为阴性,说明我们构建的脉动流培养系统能有效地模拟体内脉动流场实现种植细胞在体外的增殖、重塑,为心脏组织工程瓣的体外构建提供了一种新的实验方法。  相似文献   
8.
Segregation analysis has provided evidence suggesting the existence of a major gene for catechol-o-methyltransferase (COMT) activity in man. Five large families (4 Caucasian, 1 black), with a total of 1,189 individuals, were ascertained as part of a genetic study of blood pressure. Erythrocyte COMT activity and status at 25 polymorphic genetic marker loci were determined on more than 518 individuals in these pedigrees. Genetic linkage analysis of COMT with each of the 25 marker loci was performed in two ways: (1) using parameter estimates from segregation analysis of untransformed COMT activity, and (2) using parameter estimates from segregation analysis of the power transformation of the COMT activity that maximized the likelihood of the genetic hypothesis in each family. Tight and close linkage were excluded at 21 and 15 loci, respectively. A lod score of 1.27 at θ = 0.1 was found between the loci for COMT activity and phosphogluconate dehydrogenase (PGD). Transformation of the data had little effect on the outcome of the linkage analysis.  相似文献   
9.
A large family with an inherited reciprocal translocation (16;21) is described. An unbalanced karyotype due to adjacent-1 segregation was documented in 6 cases, whereas 25 children dying within the first year of life and 4 individuals dying at later ages probably had the same abnormality. Therefore minimal and maximal risk estimates were calculated to be 6.0% and 26.5% for female, respectively, 4.8% and 33.3% for male translocation heterozygotes. Among the karyotyped phenotypically normal offspring of male as well as female carriers the ratio of normal children to balanced carriers was not different from 1:1.  相似文献   
10.
We have determined the number and location of the nucleolar organizing regions in spermatocytes ofGraphosoma italicum (2n=12A+ XY/XX) by means of silver impregnation, chromomycin A3/distamycin A staining and fluorescencein situ hybridization. The identification of only one nucleolar organizing region located at one of the X chromosome ends has provided a suitable cytological marker to analyse the segregation of this univalent and that of the XY pseudobivalent during the first and second meiotic divisions respectively. Our results clearly show that at first meiotic metaphase the chromatids of the X chromosome are orientated with their long axes perpendicular to the polar axis. Although the kinetic activity is restricted to only one end in both X chromatids during the first meiotic division, both ends of the same chromatid have the same probability of showing such kinetic activity. In this sense, we also report that the chromatid segregation maybe initiated either at the same sister chromatid ends or at opposite ends in each chromatid. Thus, this indicates a sex chromatid independence as regards to the chromatid segregation during the first meiotic division. Throughout the second meiotic division both ends of the X chromatid are involved with the same probability in the end-to-end association to conform the XY pseudobivalent. This also implies a random localization of the kinetic activity at the ends opposite to those involved in the end-to-end association.accepted for publication by J. S. (Pat) Heslop-Harrison  相似文献   
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