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1.

目的:利用光学相干断层扫描血管成像技术(OCTA)定量分析产后6mo以上妊娠期高血压综合征(PIH)患者的视网膜微循环变化。

方法:分别测量19例PIH患者、23例正常妊娠女性(HPW)及19例未妊娠女性(CNPW)的屈光度、最佳矫正视力及眼轴长度,并使用OCTA测量三组视乳头及黄斑区血流参数、神经纤维层厚度和脉络膜厚度。所有妊娠患者数据均采集自分娩6mo以后。运用统计软件SPSS20.0,单因素方差分析比较三组间视网膜微循环相关参数的组间差异。

结果:PIH组的黄斑区无灌注区面积(FAZ)明显大于HPW组和CNPW组(均P<0.05); 三组间的黄斑区各区域视网膜浅层血管密度无差异; PIH组的视乳头各区域浅层血管密度,其中视乳头整层6mm区域、外层、下外侧、鼻外侧高于HPW组和CNPW组; 视神经纤维层平均厚度三组间无差异,但PIH组的视神经颞侧纤维层厚度明显低于HPW组和CNPW组(均P<0.05); PIH组的黄斑中心区视网膜厚度明显低于HPW和CNPW(均P<0.05); 中心凹下脉络膜厚度三组间无差异。

结论:PIH患者产后视网膜部分区域血管密度、黄斑中心区厚度及颞侧视神经纤维层厚度与HPW及CNPW组间均存在差异,提示PIH对视网膜微循环的影响可能在产后仍持续存在。  相似文献   

2.
《中国现代医生》2020,58(28):143-146
目的 了解杭州地区地中海贫血的检出情况,探讨产检中筛查地中海贫血的意义,评价平均红细胞体积(MCV)、平均血红蛋白量(MCH)及血红蛋白电泳对地中海贫血进行产前筛查的价值。方法 以2019年2月~2020年3月在我院检查的3968例育龄期妇女为研究对象,进行血常规、血红蛋白电泳及β-地贫基因检测。结果 筛查3968例育龄期妇女,疑似α-地中海贫血或缺铁性贫血共有366例(9.22%),其中妊娠中晚期孕妇有255例;疑似β-地中海贫血共有19例(0.48%),其中有4例进行β-地贫基因检测,均被确诊为β-地中海贫血,分别为βIVS-II-654/βN 突变1例,βCD17/βN 突变2例,βCD41/42/βN 1例。结论 MCV、MCH及血红蛋白电泳可以对地中海贫血进行产前筛查,整体操作较为简便。加强地中海贫血筛查及检测,可以降低出生缺陷,对优生优育具有重要意义。  相似文献   
3.
目的:利用简单序列重复区间扩增多态性(ISSR)分子标记技术对江西省锐尖山香圆进行亲缘关系和遗传结构分析,为该药材资源的保护和利用提供理论依据。方法:采集江西省4个县6个采样地的22份锐尖山香圆叶片样本,利用试剂盒法提取基因组DNA。利用64条通用ISSR分子标记引物进行聚合酶链式反应(PCR)扩增,运用聚丙烯酰胺凝胶电泳(PAGE)方法检测条带。选择NTsys 2. 10e软件,采用非加权配对算术平均法(UPGMA)计算遗传相似系数并聚类分析。利用Structure 2. 1软件分析群体遗传结构。结果:有48条ISSR引物扩增后获得了产物,多态性条带百分率处于45. 45%~100%。UPGMA聚类分析表明4个县的锐尖山香圆资源不能按照行政区域划分分别聚为一类,群体遗传结构分析表明22份锐尖山香圆群体可以划分为3个类群。结论:江西省锐尖山香圆群体间存在着基因交流,会影响该药材不同地理来源种质资源的遗传结构组成。  相似文献   
4.
Hypoalbuminemia is associated with inflammation. Despite being addressed repeatedly in the literature, there is still confusion regarding its pathogenesis and clinical significance. Inflammation increases capillary permeability and escape of serum albumin, leading to expansion of interstitial space and increasing the distribution volume of albumin. The half‐life of albumin has been shown to shorten, decreasing total albumin mass. These 2 factors lead to hypoalbuminemia despite increased fractional synthesis rates in plasma. Hypoalbuminemia, therefore, results from and reflects the inflammatory state, which interferes with adequate responses to events like surgery or chemotherapy, and is associated with poor quality of life and reduced longevity. Increasing or decreasing serum albumin levels are adequate indicators, respectively, of improvement or deterioration of the clinical state. In the interstitium, albumin acts as the main extracellular scavenger, antioxidative agent, and as supplier of amino acids for cell and matrix synthesis. Albumin infusion has not been shown to diminish fluid requirements, infection rates, and mortality in the intensive care unit, which may imply that there is no body deficit or that the quality of albumin “from the shelf” is unsuitable to play scavenging and antioxidative roles. Management of hypoalbuminaemia should be based on correcting the causes of ongoing inflammation rather than infusion of albumin. After the age of 30 years, muscle mass and function slowly decrease, but this loss is accelerated by comorbidity and associated with decreasing serum albumin levels. Nutrition support cannot fully prevent, but slows down, this chain of events, especially when combined with physical exercise.  相似文献   
5.
目的分析武汉两所医院耐碳青霉烯类肺炎克雷伯菌(CRKP)临床分离株产碳青霉烯酶的情况,以及分子流行病学特征。方法收集武汉两所医院2018年1—10月临床分离的42株非重复CRKP,采用Carba NP试验方法对菌株产碳青霉烯酶情况进行初筛,聚合酶链反应(PCR)检测碳青霉烯酶基因携带情况,采用质粒接合试验分析耐药基因的水平转移情况,应用脉冲场凝胶电泳(PFGE)进行亲缘关系分析。结果 42株CRKP菌株中14株Carba NP试验阳性,其中有10株扩增出NDM-1基因,3株扩增出KPC-2基因。共13株CRKP碳青霉烯基因检测阳性,其中12株质粒接合试验成功。PFGE分析结果显示,携带NDM-1基因的CRKP菌株共分成6型,无明显优势型;携带KPC-2基因的CRKP菌株为同一型别。结论检出产NDM-1和KPC-2的CRKP菌株,质粒接合试验提示质粒介导的水平传播在碳青霉烯酶基因的播散过程中可能起重要作用。  相似文献   
6.

Objectives

To investigate potential functions of transforming growth factor-beta (TGF-β) isoforms in maturation-stage ameloblasts during amelogenesis.

Methods

In vivo activation of TGF-β was characterized by using matrix metalloproteinase 20 null (Mmp20-/-) and wild-type (Mmp20+/+) mice. Using mHAT9d cells cultured in the presence of each TGF-β isoform, (1) cell proliferation was determined by MTS assay, (2) immunostaining with anti-cleaved caspase-3 monoclonal antibody was performed and apoptotic indices were measured, (3) gene expression was analyzed by RT-qPCR, and (4) the uptake of amelogenin into mHAT9d cells was directly observed using a fluorescence microscope.

Results

TGF-β1 and TGF-β3 were present in the enamel matrix of developing teeth which were activated by MMP20 in vivo. A genetic study revealed that the three TGF-β isoforms upregulate kallikrein 4 (KLK4) mRNA levels but downregulate carbonic anhydrase II. Moreover, TGF-β1 and TGF-β2 significantly upregulated the mRNA level of amelotin, whereas TGF-β3 dramatically downregulated the mRNA levels of odontogenic ameloblast-associated protein (ODAM), family with sequence similarity 83 member H (FAM83H), and alkaline phosphatase (ALP). Immunostaining analysis showed that the apoptosis of mHAT9d cells is induced by three TGF-β isoforms, with TGF-β3 being most effective. Both TGF-β1 and TGF-β3 induced endocytosis of amelogenin.

Conclusions

We propose that TGF-β is regulated in an isoform-specific manner to perform multiple biological functions such as gene expression related to the structure of basal lamina/ameloblasts, mineral ion transport, apoptosis, and endocytosis in maturation-stage ameloblasts.  相似文献   
7.
8.
Osteogenesis imperfecta (OI) is characterized by susceptibility to bone fractures. Other symptoms, such as easy bruising and bleeding complications during surgery necessitating transfusions, have also been reported. The aim of the cross-sectional pilot study was to assess the bleeding and bruising tendency in OI patients and to screen for possible underlying haematological disorders. Bleeding tendency was investigated using the International Society on Thrombosis and Haemostasis bleeding assessment tool (ISTH-BAT) in 22 adult OI patients. Laboratory testing was performed to investigate for bleeding disorders or abnormal coagulation. Four patients [OI type 1(n = 3), OI type 4(n = 1)] had a bleeding score (BS) fitting with a bleeding tendency, but without test results pointing to a coagulopathy. Two patients [OI type 1(n = 1), OI type 3 (n = 1)] without a bleeding tendency according to the BS had increased fibrinolysis. This is the second largest study to date addressing bleeding tendency in OI and the first study to use ISTH-BAT and elaborate laboratory testing for coagulopathies. Four patients had an increased bleeding tendency. However, laboratory testing demonstrated no bleeding disorder or abnormal coagulation. Increased fibrinolysis was demonstrated in two patients without bleeding tendency on BS. Vascular fragility as a cause of bleeding tendency in OI has been suggested earlier. Further research on bleeding tendency in OI is important.  相似文献   
9.
10.
ObjectivesThe study sought to assess the acute hemodynamic effects of iatrogenic atrial septal defect (iASD) closure following transcatheter mitral valve edge-to-edge repair (TMVR).BackgroundThe potential hemodynamic and clinical consequences of an iASD following TMVR are currently subject to controversial debates.MethodsIn 21 patients with relevant left-to-right shunt flow (50% [IQR: 38% to 60%] of systemic perfusion volume) across an iASD following TMVR, interventional closure was performed with recordings of left ventricular (LV) and right ventricular (RV) pressure-volume loops during iASD occlusion.ResultsiASD occlusion led to a volume shift from the RV (RV end-diastolic volume index: pre 102 [IQR: 80 to 120] ml/m2, post 92 [IQR: 70 to 111] ml/m2; p < 0.001) to the LV (LV end-diastolic volume index: pre 91 [IQR: 74 to 124] ml/m2, post 97 [IQR: 77 to 127] ml/m2; p < 0.001) with reduced RV (3.49 [IQR: 2.07 to 3.58] l/min/m2 vs. 2.68 [IQR: 2.07 to 3.58] l/min/m2; p < 0.001) but increased LV cardiac index (2.25 [IQR: 1.80 to 3.28] l/min/m2 vs. 2.77 [IQR: 1.90 to 3.34] l/min/m2; p = 0.039). Although RV end-diastolic pressure decreased (pre 5.0 [IQR: 4.0 to 8.5] mm Hg, post 4.5 [IQR: 3.0 to 8.3] mm Hg; p = 0.024), LV end-diastolic pressure remained unchanged (pre 11.0 [IQR: 9.5 to 14.0] mm Hg, post 13.0 [IQR: 9.0 to 15.5] mm Hg; p = 0.142). LV transmural pressure increased (7.0 [IQR: 4.0 to 11.0] mm Hg vs. 11.0 [IQR: 7.0 to 15.0] mm Hg; p = 0.001) and LV eccentricity index decreased (p < 0.001). The change in LV transmural pressure correlated significantly with the change in LV-to-RV end-diastolic volume ratio (r = 0.674; p = 0.018). Right heart failure symptoms declined at 1-month follow-up (71% vs. 35%; p = 0.003) as did New York Heart Association functional class (≥III: 48% vs. 25%; p < 0.001).ConclusionsiASD closure following TMVR leads to a volume shift from the RV to the LV with reduced pulmonary but increased systemic cardiac index and with favorable biventricular interaction at maintained LV filling pressure, resulting in a decline in heart failure symptoms at 1-month follow-up.  相似文献   
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