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41.
作者合成了13个对-苯二甲酸衍生物,其中有9个化合物尚未见文献报道。通过对HL-60细胞诱导分化活性试验,发现有两个化合物在浓度为5×10 ̄(-6)mol/L时,可使细胞分化率达55%,低于维A酸的分化率(79%,10 ̄(-7)mol/L)。  相似文献   
42.
采用淀粉凝胶电泳法对云南水族人红细胞酸性磷酸多态分布状况进行了调查,检出EAPA型6例,EAPBA型45例,EAP55例。计算出基因频率分别为:EAP^A0.2689,EAP^B0.7311.EAP在云南水族人群中的DP值为0.5185。文中对EAP在不同人群中的分布进行了比较分析。  相似文献   
43.
旅店室内空气甲醛污染对从业人员健康影响的调查报告   总被引:10,自引:0,他引:10  
本文以甲醛平均浓度为0.058mg/m3的高级宾馆为接触组和平均浓度为0.020mg/m3的普通招待所为对照组,对其从业人员的健康状况进行调查比较,结果表明:接触组的眼、鼻、咽刺激征、呼吸道症状、头晕、疲劳感、皮肤干燥、月经不调、多汗等自觉症状阳性检出率明显高于对照组,差异具有显著性。提示,旅店业甲醛污染对从业人员健康的影响不能忽视。改善室内环境、降低空气中甲醛浓度,对于保护人体健康具有重要意义。  相似文献   
44.
目的 为了解中日儿童及成人的步行和体成分及其相互关系.方法 以中国上海市和日本琦玉县的小学生和成人为对象,采用西铁城 TW02-001电子式步数计测定步行量,FUTREX-5000A体成分测定仪测量体脂百分比.结果 1.中国男女小学生的平均每日步行量分别为12426步和10387步,低于日本小学生(男15 340步,女11 617步),体脂百分比中国男女生分别为21.2%和15.8%,高于日本(男18.9%,女13.1%).中国男女成人的平均每日步行量分别为9826步和8748步,高于日本成人(男:8411步,女7599步);体脂百分比分别为17.5%(男)和25.8%(女),而日本男性为19.8%,女性为26.0%.2.不同活动水平的小学生和成人,其血压和体成分均有差异,步行量高者的血压和体脂百分比都较低.本研究还计算出以肱三头肌皮脂厚度以(X)推测儿童体脂百分比(Y)的回归方程为:Y=10.6646+0.5856X.结论 作为日常生活的步行可促进肥胖发生率的降低.  相似文献   
45.
The origins of the projections of the superior colliculus to the dorsal lateral geniculate nucleus and to the pulvinar in Dutch-belted rabbits were investigated using horseradish peroxidase (HRP) methods. Following injections of HRP in the dorsal lateral geniculate nucleus, retrogradely labeled neurons were found in the upper two-thirds of the stratum griseum superficiale of the ipsilateral superior colliculus. Most of the labeled somata were spindle-shaped, and their major axes tended to be perpendicular to the surface of the superior colliculus. In contrast, following injections of the pulvinar, labeled neurons were found in the lower third of the ipsilateral stratum griseum superficiale. In these cases, the labeled somata were larger than those labeled following dorsal lateral geniculate injections and were multipolar in shape.  相似文献   
46.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body wt.34 during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats.  相似文献   
47.
HK239: a P2 related temperate phage which excludes rII mutants of T4   总被引:7,自引:0,他引:7  
E K Dhillon  T S Dhillon 《Virology》1973,55(1):136-142
  相似文献   
48.
A previous limited study demonstrated that Mycobacterium tuberculosis isolates with a mutation at amino-acid position 315 of katG (Delta315) exhibited high-level resistance to isoniazid and were more frequently resistant to streptomycin. In the present study, isoniazid-resistant M. tuberculosis isolates from 8,332 patients in The Netherlands (1993-2002) were screened for the Delta315 mutation. Isoniazid resistance was found in 592 (7%) isolates, of which 323 (55%) carried Delta315. IS6110 restriction fragment length polymorphism analysis showed that Delta315 isolates occurred in clusters, suggesting recent transmission, at the same frequency as isoniazid-susceptible isolates. In contrast, other isoniazid-resistant isolates clustered significantly less frequently. Delta315 isolates were high-level isoniazid-resistant, streptomycin-resistant and multidrug-resistant significantly more often, and may have a greater impact on public health, than other isoniazid-resistant isolates.  相似文献   
49.

Background

Variants in GBA are the most common genetic risk factor for Parkinson's disease (PD), and are especially prevalent in the Ashkenazi Jewish (AJ) population. However, most studies on GBA in AJ genotype only seven selected Gaucher-associated pathogenic variants rather than sequencing the whole gene, which may leave carriers of PD-associated GBA variants undiscovered.

Methods

GBA was fully sequenced using molecular inversion probes (MIPs) and Sanger sequencing in 735 AJ PD patients and 662 AJ controls, from Israel and New York. Additional AJ control data (n?=?3044) from the Inflammatory Bowel Disease Exome Portal was used.

Results

Full GBA sequencing increased the number of variants discovered by 17.4%, compared to targeted genotyping. An additional 17 PD patients were identified with GBA-associated PD. The p.E326K variant was found in 1.6% of AJ PD patients, making it the second most common PD-associated GBA variant in AJ. GBA variants were found in 18% of PD patients and 7.5% of controls (OR?=?2.7, 95%CI?=?1.9–3.8, p?<?0.0001).

Conclusion

Without full sequencing of GBA, or at minimum including p.E326K in the genotyping panel, a significant proportion of variant carriers go undiscovered and may be incorrectly assigned as non-carriers in studies or clinical trials.  相似文献   
50.
Refractoriness to Gal N toxicity occurs especially in fetal rats, newborn rats, and in rats after partial hepatectomy. An injury however (laparotomy, incision on the back or ip BaSO4 suspension), prior to Gal N administration, also inhibits Gal N toxicity. In all these circumstances high levels of rat α2-macrofetoprotein (αMFP) occur. This protein is an acute phase reactant and is identical to rat α2-macroglobulin. αMFP isolated from the serum of injured rats and then administered to normal rats strongly inhibits Gal N toxicity. When time interval between the preceding injury, provoking αMFP production and Gal N administration shortens, the inhibiting effects are less and αMFP production remains low.During resistance to Gal N, the primary and secondary biochemical lesions of Gal N persist and the protecting effect of αMFP must be due to another mechanism, operating in later phases of cell injury. Very probably this is attributable to the stabilizing effect on membranes of hepatocytic organelles and the plasma membranes. As αMFP is an acute phase reactant the importance of these proteins to the course of hepatitis must be considered.  相似文献   
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