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101.
102.
Shujiao He Minjie Zhang Jieying Li Weiqiang Zhao Li Yu Ying Han Yanbin Pang 《The Journal of international medical research》2022,50(5)
A Y842D mutation within the activation loop of fms-like tyrosine kinase 3 (FLT3) has been shown to confer strong resistance to sorafenib in vitro. Whether this type of mutation exerts clinically significant effects in patients with acute myeloid leukaemia (AML) remains unclear. Here, a novel Y842D activating mutation within the kinase domain of FLT3, in a pregnant patient with de novo hyperleucocyte acute myeloid leukaemia, is described. Following induction failure with standard dose idarubicin and cytarabine (IA), the patient received re-induction combined with midostaurin, a promising agent targeting mutant-FLT3, and IA regimen. Fortunately, morphological remission was achieved. During the period of midostaurin treatment, the patient exhibited a symptom that was characteristic of differentiation syndrome, which disappeared following treatment with methylprednisolone. The present case revealed that Y842D, an uncommon activating mutation in the activation loop of FLT3, may be a midostaurin-sensitive mutation type in patients with acute myeloid leukaemia. 相似文献
103.
补体C3、补体C4联合甲状腺自身抗体检测对桥本甲状腺炎诊断和预后的意义 总被引:2,自引:0,他引:2
目的探讨补体C3、补体c4、抗甲状腺球蛋白抗体(TGAb)、甲状腺过氧化物酶抗体(TPOAb)和促甲状腺激素受体刺激抗体(TSAb)检测对桥本甲状腺炎(HT)的诊断价值和病情发展判定的意义。方法选择HT患者120例作为HT组,同期就诊的Graves病患者110例作为Graves’病组,30例健康体检者作为对照组。3组患者分别检测补体C3、补体C4、TGAb、TPOAb和TSAb,并进行比较。结果HT组和Graves病组TGAb、TPOAb和TSAb水平和阳性率较对照组明显升高,HT组TGAb和TPOAb的水平和阳性率升高较Graves病组升高更为明显,而TSAb的水平和阳性率Graves病组较HT组更为明显。HT组的补体C3和补体C4水平较对照组和Graves病组明显降低,而对照组和Graves病组无显著性差异。HT组中甲减亚组补体C3和补体C4水平的变化较甲功正常亚组和甲功亢进亚组明显降低。结论HT是最常见的自身免疫性甲状腺疾病之一,因其血清学诊断标准不具特异性,联合检测补体C3、补体C4和甲状腺自身抗体对提高HT的临床诊断以及判断病情发展具有较重要的临床意义。 相似文献
104.
Renfeng Li Xiangqin Tian Junzeng Pang Linyue Li Jiakang Yuan Zhuangzhuang Tian Ziliang Wang 《Viruses》2022,14(7)
The timely and accurate diagnosis of porcine epidemic diarrhea virus (PEDV) infection is crucial to reduce the risk of viral transmission. Therefore, the objective of this review was to evaluate the overall diagnostic accuracy of rapid point-of-care tests (POCTs) for PEDV. Studies published before 7 January 2022 were identified by searching PubMed, EMBASE, Springer Link, and Web of Science databases, using subject headings or keywords related to point of care and rapid test diagnostic for PEDV and PED. Two investigators independently extracted data, rated risk of bias, and assessed the quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The bivariate model and the hierarchical summary receiver operating characteristic (HSROC) model were used for performing the meta-analysis. Threshold effect, subgroup analysis, and meta-regression were applied to explore heterogeneity. Of the 2908 records identified, 24 eligible studies involving 3264 specimens were enrolled in the meta-analysis, including 11 studies on evaluation of lateral flow immunochromatography assay (ICA)-based, and 13 on nucleic acid isothermal amplification (NAIA)-based POCTs. The overall pooled sensitivity, specificity and diagnostic odds ratio (DOR) were 0.95 (95% CI: 0.92–0.97), 0.96 (95% CI 0.88–0.99) and 480 (95% CI 111–2074), respectively; for ICA-based POCTs and the corresponding values for NAIA-based, POCTs were 0.97 (95% CI 0.94–0.99), 0.98 (95% CI 0.91–0.99) and 1517 (95% CI 290–7943), respectively. The two tests showed highly comparable and satisfactory diagnostic performance in clinical utility. These results support current recommendations for the use of rapid POC tests when PEDV is suspected. 相似文献
105.
Y Wang K Pang A E Jacobson R Lessor K C Rice B Hoffer 《Pharmacology, biochemistry, and behavior》1986,24(5):1403-1407
The discovery of phencyclidine (PCP) receptors has stimulated the search for specific PCP antagonists. A direct product of this research is metaphit, an irreversible PCP ligand, which has recently been synthesized. In this study we examined the effects of metaphit on the responses of hippocampal neurons to PCP. On the basis of unfiltered action potential durations, hippocampal cells were divided into two groups, complex-spike cells and theta neurons. Local application of PCP caused inhibitions of the spontaneous firing rates of complex-spike cells. Metaphit, locally applied, antagonized approximately 50% of these responses, while the remaining responses were unaffected. In contrast, PCP caused increases in the spontaneous firing rates of theta cells and in almost all cases, these responses to PCP were attenuated by metaphit administration. These effects of metaphit were specific for PCP as the responses to locally applied norepinephrine were not altered by metaphit. The data suggest two mechanisms of action of PCP in the hippocampus. In addition, these mechanisms may be localized in part to different cell types. 相似文献
106.
K Pang S W Johnson S Maayani R Freedman 《Pharmacology, biochemistry, and behavior》1986,24(1):127-134
The depressant effects of phencyclidine [1-(1-phenylcyclohexyl) piperidine, PCP] and three of its analogs (m-amino-PCP, m-nitro-PCP, and PCP-methyliodide) on the spontaneous action potential discharge of cerebellar Purkinje neurons in urethane-anesthetized rats were examined in this study. Both intraperitoneal injection and micro-pressure ejection were employed as routes of drug administration. The relative potency after parenteral administration corresponded closely with previous findings in behavioral test paradigms. PCP and m-amino-PCP were equipotent, m-nitro PCP was less potent than either PCP or m-amino-PCP, and PCP-methyliodide showed almost no activity. After local administration onto neurons, m-amino-PCP was significantly more potent than PCP, while PCP, m-nitro-PCP, and PCP-methyliodide were equipotent. Tritiated PCP, m-nitro PCP, and m-amino PCP have similar distribution and metabolism in cerebellum. PCP-methyliodide, a quaternary ion, does not cross the blood brain barrier. M-nitro PCP is appreciably less ionized at pH 7.4 than PCP or m-amino-PCP and, therefore, may be more easily sequestered into lipids. Differences between PCP and its analogs found in experiments which employ parenteral administration may reflect differences in drug distribution. These differences are minimized when these drugs are administered directly onto neurons via pressure microejection. 相似文献
107.
目的:了解胰岛素样生长因子(IGFⅠ)及其结合蛋白(IGFBPs)水平在儿童肾病综合征(NS)中的变化。方法:用免疫放射法和放射免疫法对20名NS患儿,即NS活动期组(NSA组,n=11)和NS缓解期组(RE组,n=9)进行了血清IGFⅠ和IGFBPs水平测定;并以同年龄组正常儿童(NC组,n=10)作对照。结果:与NC组比较,NSA组血清IGFⅠ、IGFBP3明显下降(P<001),IGFBP1和IGFBP2均明显升高(P<001);RE组的血清IGFⅠ及IGFBP1、IGFBP2和IGFBP3均可恢复正常;NSA组血清IGFBP3与白蛋白存在明显相关关系(r=076,P<001)。结论:NS活动期存在着IGFⅠ和IGFBPs的异常改变,但缓解期可完全恢复正常;IGFⅠ和IGFBPs的异常改变可能与NS患儿生长障碍有关 相似文献
108.
作者设计并合成了8个γ-氨基丁酸(GABA)的衍生物(Ⅳ_(a-b)),使GABA的酯通过亚胺键,连接在一个易于通过血脑屏障的亲脂性载体上。合成的8个标题化合物,均用NIH提出的抗癫痫药物开发程序进行评价,结果化合物Ⅳ_b和Ⅳ_f表现出有效的抗惊厥活性。 相似文献
109.
中国人2型糖尿病合并高甘油三酯血症患者脂蛋白酯酶基因突变及功能分析 总被引:5,自引:0,他引:5
目的 研究中国人2型糖尿病合并高甘油三酯血症患者脂蛋白醒酶(1ipoprotein lipase,LPL)基因突变及对酶功能的影响,从脂代谢途径探讨引发糖尿病的遗传因素。方法 对高甘油三酯及血脂正常的2型糖尿病患者和正常人的LPL基因进行研究。利用PCR—SSCP、PCR—RFLP及DNA测序技术对LPL基因的启动子和10个外显子区域进行突变检测,针对特异位点进行体外定点突变和酶活力表达研究,利用网上工具平台Swiss-PDB Viewer对正常和突变蛋白进行二级结构模拟分析。结果 在177例高甘油三酯2型糖尿病患者中检测到4种错义突变:Ala71Thr、Val181IIe、Glyl88Glu和Glu242Lys,在正常血脂的糖尿病患者和健康人组中没有检出以上突变。这4种突变位于进化上高度保守的氨基酸位点,并分别在高度保守的外显子3、5及6区域。体内和体外酶活力研究表明,这4个突变均引起了酶活力降低甚至失活,其改变程度可以从它们所在序列的保守性、在酶功能结构城中的相对位置、相应的二级结构改变和氨基酸特性获得解释。结论 在受累个体中,LPL突变是引起患者血浆甘油三酯升高的直接原因,是其发展成2型糖尿病的遗传性易感因素。 相似文献
110.
Ideal halogen-free instinct flame-retardant waterborne polyurethanes have high flame-retardant efficiency, environmental friendliness, fine compatibility, and good thermostability. Phosphorus flame-retardants are currently widely used in halogen-free instinct flame-retardant waterborne polyurethanes (HIFWPU), especially those with phosphorous–nitrogen co-structures. Phosphorous–nitrogen HIFWPU have become a hotspot because their co-structures provide higher flame-retardance as compared to waterborne polyurethanes. This review introduces three main types of HIFWPU based on composition, performance and application. HIFWPU not only have improved flame-retardance but also satisfy the various requirements for functionality. HIFWPU have been widely developed in textile, furniture, automobile, and aerospace applications.Ideal halogen-free instinct flame-retardant waterborne polyurethanes have high flame-retardant efficiency, environmental friendliness, fine compatibility, and good thermostability. 相似文献