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81.

Background and Objectives

Renal relapse is a very common manifestation of IgA nephropathy (IgAN). The clinical characteristics and long-term outcomes of this condition have not yet been carefully explored.

Design and Patients

Patients with biopsy-proven IgAN between January 2005 and December 2010 from three medical centers in China was a primary cohort of patients. From January 2010 to April 2012, data of an independent cohort of IgAN patients from Ren Ji Hospital, Shanghai, China was collected using the same inclusion and exclusion criteria. These patients formed the validation cohort of this study.

Results

Of the patients with biopsy-proven IgAN from three medical centers, 489 patients achieved remission within 6 months following the therapy. Additionally, 76 (15.5%) of these patients experienced a relapse after achieving remission. During the median follow-up period of 66 months, 6 patients (1.4%) in the non-relapse group experienced renal deterioration, compared with 22 patients (29.6%) in the relapse group. Our study indicated that each 1-mmHg increase in the baseline diastolic blood pressure (DBP) was associated with a 4.5% increase in the risk of renal relapse; additionally, the male patients had a 3.324-fold greater risk of relapse compared with the female patients according to the adjusted multivariate Cox analysis. The nomogram was based on 489 patients achieved remission. The predictive accuracy and discriminative ability of the nomogram were determined by concordance index (C-index) and calibration curve. The results were validated using bootstrap resampling on the validation cohort.

Conclusions

This study demonstrated that renal relapse is a potential predictor of prognostic outcomes in patients under the current therapeutic regimens for IgAN. And male patients with higher diastolic blood pressure had a greater risk of experiencing relapse.  相似文献   
82.
Plasmonics - Nano-structured metals have attracted a great amount of attention in recent years due to the exciting plasmonic and photonic properties. However, the intrinsic high loss of the metals...  相似文献   
83.
84.
嵌合体大鼠是研究人类疾病的重要动物模型。用囊胚注射法研究了大鼠内细胞团(ICM)和胎儿神经干细胞(FNS)构建嵌合体的潜力。结果发现来自黑色(DA)大鼠第5天(D5)和第6天(D6)囊胚的ICM细胞注入D5 Sprague-Dawley(SD)大鼠囊胚后得到3只嵌合体大鼠;D5 SD大鼠ICM细胞注射入D5 DA囊胚后得到4只嵌合体大鼠;而体外培养的DA或SD大鼠ICM细胞注射后均未能获得嵌合体大鼠。本研究用大鼠胎儿神经干细胞(rFNS)和LacZ转染的rFNS构建嵌合体,未能获得嵌合体大鼠;但在LacZ转染的SD rFNS注射到DA大鼠囊胚后发育来的41只胎儿中,有2只胎儿其组织切片中发现少量LacZ阳性细胞。结果表明DA和SD大鼠ICM具有参与嵌合体发育的潜力,但ICM细胞经体外培养后构建嵌合体的潜力显著下降(P<0.05);大鼠胎儿神经干细胞构建嵌合体的潜力较低,可能仅具有参与早期胚胎发育的潜力。  相似文献   
85.
Qiu J  Peng Q  Zheng Y  Hu J  Luo X  Teng Y  Jiang T  Yin T  Tang C  Wang G 《Biochimica et biophysica acta》2012,1821(10):1361-1369
Angiogenesis plays remarkable roles in the development of atherosclerotic rupture plaques. However, its essential mechanism remains unclear. The purpose of the study was to investigate whether inhibitor of DNA binding-1 or inhibitor of differentiation 1 (Id1) promoted angiogenesis when exposed to oxidised low-density lipoprotein (oxLDL), and to determine the molecular mechanism involved. Using aortic ring assay and tube formation assay as a model system, a low concentration of oxLDL was found to induce angiogenic sprouting and capillary lumen formation of endothelial cell. But the Id1 expression was significantly upregulated by oxLDL at low and high concentrations. The Id1 was localised in the nuclei of the human umbilical vein endothelial cells in the control group and in the high-concentration oxLDL group. Id1 was translocated to the cytoplasm at low oxLDL concentrations. The nucleocytoplasmic shuttling at low oxLDL concentration was inhibited by treatment with the nuclear export inhibitor leptomycin B. Protein kinase A (PKA) inhibitor H89 promoted nuclear export of Id1, and phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 reduced the nuclear export of Id1. PI3K inhibition blocked oxLDL-induced angiogenesis. Low concentrations of oxLDL promoted angiogenic sprouting and capillary formation. And this process depends on nuclear export of Id1, which in turn is controlled by the PI3K pathway. This report presents a new link between oxLDL and Id1 localisation, and may provide a new insight into the interactions of ox-LDL and Id1 in the context of atherosclerosis.  相似文献   
86.
科尔沁沙地樟子松能否发生冬季“生理干旱”伤害   总被引:1,自引:1,他引:0  
在内蒙古东部半干旱地区分别测定了春、秋两季栽植的樟子松苗越冬期间针叶含水量和蒸腾强度的变化,测定了针叶的致死临界含水量并在室内模拟了生理干旱伤害症状以探讨发生冬季生理干旱伤害的可能性.结果表明秋植苗针叶含水量1月份就已降到初始致死含水量以下而春植苗针叶含水量始终显著高于初始致死含水量并顺利越冬.含水量与蒸腾强度的对比表明甚至在冻土期内,针叶仍有某种水分补充来源.模拟实验中出现的针叶伤害症状和秋植苗野外伤害症状一致.结论认为该地区已正常成活的春季造林苗不大可能发生冬季生理干旱伤害.  相似文献   
87.
88.
人β神经生长因子在大肠杆菌中的高表达   总被引:2,自引:0,他引:2       下载免费PDF全文
张剑  张林元 《微生物学报》1997,37(6):429-433
将编码人β神经生长因子(Huβ-HGF)的基因克隆到由T7噬菌体启动子控制的pET11c大肠杆菌表达载体中,重组质粒经鉴定含有Huβ-NGF基因,未解聚的表达产物经SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE),结果显示出二聚体27kD的蛋白带。而完全解聚的表达产物SDS-PAGE显示出一条13β5kD单体带。经凝胶电泳扫描,表达带占菌体总蛋白的14.5%。用兔抗鼠β—NGF的多克隆抗体进行的Western-Blot的结果表明,二聚体同单体都有免疫原性。在生物活性的鉴定中,菌体表达产物可以使小鸡鸡胚的背根神经节产生神经元突起,由此可以证明该表达产物有较高的生物活性。  相似文献   
89.
[目的]优化红脉穗螟寄生蜂繁育技术,为该虫的生物防治提供参考。[方法]通过室内饲养研究了红脉穗螟幼虫寄生蜂褐带卷蛾茧蜂和蛹寄生蜂周氏啮小蜂(海南种)对4种昆虫的寄生效果,并对最佳接种比例进行筛选。[结果]褐带卷蛾茧蜂对大蜡螟幼虫寄生效果优于米蛾幼虫,且对黄粉虫和大麦虫幼虫不表现寄生特性,褐带卷蛾茧蜂和大蜡螟幼虫的最佳接种比例为1∶1和2∶1,其中在2∶1接种比例处理中的寄生率和单寄主产蜂量分别为76.67%和34.60头;4种昆虫蛹均可用于繁育周氏啮小蜂,从寄主的繁育成本和寄生效果分析,以黄粉虫蛹效果较最佳,接种蜂虫比以2∶1为宜,此时的单寄主产蜂量为148.60头。[结论]寄主和接种比例不同会影响寄生蜂的寄生效果,本研究中褐带卷蛾茧蜂适宜寄主为大蜡螟,最优蜂虫比为1∶1和2∶1,周氏啮小蜂(海南种)适宜寄主为黄粉虫,最优接种蜂虫比为2∶1。  相似文献   
90.
[目的]青皮为国家Ⅱ级保护植物,海南青皮林省级自然保护区是世界上仅存面积最大的2片滨海青皮林之一,2020年发现保护区内青梅山天牛严重危害青皮,为此有必要对该虫进行风险分析并确定风险等级。[方法]采用有害生物风险分析程序和方法,从分布情况、潜在经济危害性、受害寄主的经济重要性、传入的可能性、风险管理等5个方面,对青梅山天牛对海南省青皮林的风险性进行定性和定量综合评估。[结果]青梅山天牛的风险综合评估值(R)为2.05,属高度危险有害生物。[结论]青梅山天牛已经对海南青皮林保护区的青皮造成了严重影响,需从检疫管理、防控技术研发、生物生态学基础研究等方面对青梅山天牛进行风险管理。  相似文献   
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