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91.
中国人戈谢病基因突变的分析   总被引:1,自引:0,他引:1  
目的 回顾及分析中国人戈谢病(Gaucher disease,GD)的基因突变类型,观察其与临床表型的相关性.方法 用基因分析的方法包括用特异限制性内切酶酶切PCR产物,检测中国人戈谢病患者已知突变位点;对含有未知突变基因的个体采用长链PCR方法,分段扩增葡萄糖脑苷脂酶的功能基因,再用巢式PCR分别扩增功能基因的外显子序列,进行DNA序列测定.结果 总结本实验室检测到的40种突变类型,常见的突变等位基因为L444P,占突变基因的33.O%,其他较常见的突变为F213I、N188S、V375L和M416V.结论 中国人GD患者中起码存在40种突变类型,基因突变类型谱与白种人有明显的区别.目前已明确70%的基因突变类型,通过基因分析进行GD的临床诊断和产前诊断已成为可能.  相似文献   
92.
Terrestrial risk assessments for pesticide exposure is generally based on a limited number of toxicity data. The protection target for these assessments requires an extrapolation from species for which toxicity data are available to other species with unknown sensitivity to be able to protect these as well. Our ability to extrapolate toxicity endpoints between species is a major source of uncertainty in risk assessment. Most analyses of interspecies extrapolation in avian risk assessments have dealt with acute toxicity data. It was suggested that, in the absence of a strong rationale to the contrary, we should assume that reproductive data is at least as variable as acute data and that strategies developed for acute data could be applied to long term toxicity data as well. Considering only the two main bird test species for which reproduction data are available (Mallard and Northern Bobwhite), a comparison of the interspecies standard deviation for both acute and reproduction data suggests that the two are equally variable. Analysis of a very limited data set also suggests that this conclusion holds regardless of which endpoint is triggered in the reproduction study. However, the relative sensitivity of the two species established from acute test data appears to be reversed in the case of reproductive data. In addition there seems to be no reason to believe that bodyweight is a factor in helping birds cope with the rigours of chronic dosing, which is in contrast with the acute dosing situation. This suggests that the best extrapolation technique for reproduction test data should be independent of phylogeny and independent of bodyweight scaling. The simplest such method is the one that was proposed by Luttik and Aldenberg (1995, 1997) for both birds and mammals.  相似文献   
93.
94.
Muller  NL; Webb  WR; Gamsu  G 《Radiology》1985,156(3):761-765
Possible signs of paratracheal lymphadenopathy on the posteroanterior (PA) chest radiograph were assessed in 98 patients and correlated with computed tomography (CT). The nodes were normal in size in 62 patients and enlarged (greater than 15 mm) in 36. Among the latter group, widening of the right paratracheal stripe was seen in 11 (31%) and enlargement of the azygos node in 15 (42%). While the lateral contour of the superior vena cava (SVC) was convex in 46 patients (47%), 81 (83%) had an increased density in the region of the SVC. When all four parameters were combined, lymphadenopathy could be detected on the PA view in 87 patients (89%). CT demonstrated that the enlarged nodes were anterolateral rather than directly lateral to the trachea and also immediately posterior to the SVC, explaining the findings on the PA radiograph.  相似文献   
95.
The double-fissure sign: a motion artifact on thin-section CT scans   总被引:1,自引:0,他引:1  
Mayo  JR; Muller  NL; Henkelman  RM 《Radiology》1987,165(2):580-581
A motion artifact has been observed that may affect the number of fine interstitial lines seen at thin-section (1.5-mm-collimation) computed tomography (CT) for the evaluation of interstitial lung disease. In 14 of 42 patients, one or both major fissures appeared as two parallel lines rather than as a single line. This was more common in the left lung base. Using a phantom, the authors were able to reproduce the phenomenon by simulating cardiac motion. Therefore, this motion may lead to an artifactual increase in the number of interstitial lines.  相似文献   
96.
97.
Rank  BH; Moyer  NL; Hebbel  RP 《Blood》1988,72(3):1060-1063
Since it is not known why sickle RBCs tend to undergo microvesiculation, we have investigated their susceptibility to thermal stress. While normal RBCs start to vesiculate at 49.0 +/- 0 degrees C (n = 14), sickle RBCs begin to vesiculate at 47.9 +/- 0.5 degrees C, with a range of 46.5 to 48.5 degrees C (n = 14). This abnormality is reproduced by treating normal RBCs with phenazine methosulfate (PMS), which stimulates the excess intracellular generation of superoxide characteristic of sickle RBCs. For PMS-treated RBCs, there is a strong correlation between membrane protein thiol oxidation and vesiculation temperature (r = .977, P less than .001). The abnormal vesiculation temperature of both unmanipulated sickle RBCs and PMS-treated RBCs is significantly improved by treatment of the RBCs with dithiothreitol. The most dense sickle RBCs are most prone to vesiculation during thermal stress, and they are the subpopulation having the greatest amount of thiol oxidation. We conclude that the tendency of sickle RBCs to vesiculate during thermal stress is further evidence for functional abnormality of the RBC cytoskeleton due to thiol oxidation.  相似文献   
98.
Gonias  SL; Figler  NL; Braud  LL 《Blood》1988,72(5):1658-1664
Streptokinase-plasmin complex (SkPl) was prepared with human plasminogen. Regulation of SkPl and plasmin by the plasma proteinase inhibitors, alpha 2-antiplasmin (alpha 2AP) and alpha 2-macroglobulin (alpha 2M), was studied as a function of temperature in plasminogen- depleted human plasma, mouse plasma, and solutions of purified proteins. The reaction of plasmin with proteinase inhibitors in human plasma was complete. alpha 2AP was the predominant inhibitor. The fraction of alpha 2M-plasmin recovered was not affected significantly by incubation temperature. In contrast, the reaction of SkPl with human proteinase inhibitors was markedly temperature dependent. The apparent second-order rate constant for the reaction of SkPl with purified alpha 2AP at 37 degrees C (1.5 x 10(2) mol/L-1 s-1) was greater than 150-fold higher than the constant derived at 4 degrees C. In human plasma and in solutions containing mixtures of purified human proteins, alpha 2AP was the principal inhibitor of SkPl. Elevating the temperature enhanced the reaction of SkPl with alpha 2AP and alpha 2M comparably. Equivalent results were obtained when incubations were performed in platelet-rich plasma (PRP) or whole blood. In murine plasma, SkPl reacted readily with the proteinase inhibitors. The principal inhibitor of SkPl was alpha 2M. Maximum reaction between SkPl and murine alpha 2M was observed at 37 degrees C; however, significant reaction also occurred at 4 degrees C. alpha 2 AP was the predominant inhibitor of plasmin in mouse plasma. Reaction of alpha 2AP with SkPl in murine plasma was significant only after the alpha 2M was inactivated with methylamine. These results were not affected by platelets or whole blood cells. We conclude that the thrombolytic efficacy of streptokinase reflects not only the nature of the plasminogen activator complex but also the function of the proteinase inhibitors.  相似文献   
99.
Aim:  To study CRP values and relate it to outcome in infants with antenatal diagnosis of gastroschisis, exomphalos and other surgical conditions.
Methods:  Over five years, infants admitted to our neonatal unit with gastroschisis, exomphalos and other surgical diagnoses were identified. Serum CRP measurements in first 5 days were studied. Group one included 33 gastroschisis patients, group two, 18 exomphalos patients, and group three, 38 patients with other surgical diagnoses. Outcome measures included TPN days, time to full feeds and duration of hospitalization.
Results:  Infants with gastroschisis were more premature (36.9 vs 38.1 weeks) with lower birth weights (2515 vs 3078 g), than infants with exomphalos. CRP values on admission in gastroschisis group were significantly higher than exomphalos and other diagnoses groups (33.7 ± 6.4 vs 8.8 ± 6.0 vs 5.7 ± 2.0, respectively, p   <   0.05). All blood cultures were sterile. There was no relationship between high CRP and death or adverse outcome (TPN days, time to full feeds or duration of hospitalization) in the gastroschisis group.
Conclusion:  Infants with gastroschisis exhibit high early CRP, which may not indicate sepsis or adverse outcome. This increase can complicate the assessment of these infants. Clinicians should be aware of this finding as it could inform management decisions in this group.  相似文献   
100.
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