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1.
《European journal of medical genetics》2022,65(6):104495
Spondyloepimetaphyseal dysplasias (SEMDs) belong to a clinically and genetically heterogeneous group of inherited skeletal disorders defined by a defect in the growth and shape of vertebrae, epiphyses and metaphyses. Rhizomelic SEMD is characterized by a disproportionate small stature caused by severe shortening and deformation of the limbs’ proximal bones, with the cranio-facial sphere unaffected. We report a second individual, an 8-year-old girl, with autosomal recessive rhizomelic SEMD associated with a homozygous exonic missense variant, c.226G > A p.(Glu76Lys), in GNPNAT1 identified by trio genome sequencing. Our data corroborate the recent findings of Ain et al. and further delineate the clinical and radiographic features of this form of SEMD associated with rhizomelic dysplasia while outlining a potential hotspot in this newly described genetic disorder. 相似文献
2.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
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目的 建立小鼠溃疡性结肠炎模型。方法 给小鼠自由饮用5%葡聚糖硫酸钠(DSS)溶液7d后,改为蒸馏水自由饮用10d,如此进行4个循环,每天观察症状。在第1个循环和第4个循环后剖杀小鼠,取出整段结肠行实体显微镜观察及切片组织学研究。结果 所观察的症状、实体显微镜像、组织学病理改变均与人类溃疡性结肠炎类似。结论 此模型制作方法简便,重复性良好,可应用于多种实验研究。 相似文献
6.
Platelet factor 4 ( PF4) is a negativehematopoietic factor.It can inhibit the prolifera-tion of endothelial cells and hematopoietic stem/progenitor cells,particularly megakaryoryocyticcells,reversibly[1] ,inhibit DNA synthesis,blockcell cycle progression during S phase and reducethe sensibility of normal hematopoietic stem/pro-genitor cells,but not some cancer or leukemia celllines,to cytotoxic drugs and ionizing radia-tion[2 - 3] ,and it also can cause a population in-crease of the stem cel… 相似文献
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Objective Based on the Helical Ventricular Myocardial Band (HVMB) theory proposed by Torrent-Guasp,the ventricular myocardial hand extends from the root of the pulmonary artery to the root of the aorta with two helical coils.This new theory is considered as a revolutionary concept for further understanding the global, three-dimensional and functional architecture of the ven- tricular myocardium. No repot had described techniques for disecting HVMB while keepin~ the integrity of the coronmy artery sys- tern. We explored techniques for dissecting HVMB in swine.Methads 33 fresh swine hearts were randomly divided intoll groups, 3 bearts in each. 160% barium sulfate (type I)suspmmion was injected into the coronary artery system. The coronary arteries were li- gated. The strial tissue was removed following puuing the hearts in boiling water then cooling for several hours. The superficial coro- nary vessels and fat tissue around the atrio-ventricular taxi inter-ventricular sulcus we~'e preserved. Some branches of the left anterior descending artery, distal segment, of posterior descending branch, and middle and distal segment of obtuse marginal branches were mu- tilated appropriately. HVMB dissection was completed with fingers in accordnce with Torrent Guasp' s technique. Results A contin- ued bundle of muscle, originated at the root of pulmonary artery and ended at the root of aorta, was unwrapped along the major dire- tion of the cardiac muscle fiber in all of the 33 hearts with spating of the coronary artery. The swine hearts' ventricular myocandium was cumosed of two loops, with basal loop firm the root of the pulmonart artery to the anterior papillary muscle and apical from the beginning of the anterior papillary muscle to the root tithe aorta. Each loop consisted of two segments: the right segment-coincid- ing with the right ventricular free wall and the left segment-coinciding with the basal d the left ventricular free wall. Posterior papillary muscle, which belongs to the descendant segment, denmrcated the border between the descendent and the ascendant of the HVMB's apical loop. Conclusion Although controversies about the theory of the HVMB remain, we have dissected the HVMB in the swine hearts' ventricular myocardium successfully with sparing of the coronary artery systems. This dissection procedure provides technical information for the studies of associated diseases based on the theory of HVMB. 相似文献
8.
本文报道57例白血病血清铜,锌含量的测定结果。白血病治疗前血清铜升高,铜/锌值增大;治疗后,病情缓解者下降,未缓解者则更高。血清锌在治疗前后无何差异。急性淋巴细胞性白血病骨髓中白血病细胞百分数与血清铜浓度呈正相关。检测血清铜,锌对白血病疗效的预测及判断预后有一定意义。 相似文献
9.
Chromatin zinc was studied using X-ray microanalysis of spermatozoa obtained from split-ejaculate fractions. Chromatin zinc, expressed as intensity ratio between zinc and sulphur (Zn/S), was unrelated to seminal zinc concentration, but was related inversely to markers of seminal vesicular secretion (fructose concentration and the proportion of zinc bound to ligands of seminal vesicular origin). It is concluded that the content of zinc in sperm chromatin can be reduced by the action of zinc ligands of seminal vesicular origin. An abnormally high contribution of seminal vesicular fluid to sperm-rich fractions of the ejaculate thus creates a risk of depleting chromatin zinc and thereby impairing zinc-dependent chromatin stability. 相似文献
10.
采用正交试验优选出最佳条件为:当乙酰乙酸乙酯为0.2moL时,硫酸铁铵0.7g,环乙烷10mL。乙酰乙酸乙酯和惭二醇摩尔比为1:1.5,反应时间为5h。所得产率为59.2%。 相似文献