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991.
We evaluated renal biopsies from 34 children with IgA nephropathy or Henoch Schönlein purpura to further characterize the ultrastructural features of the glomerular membranopathy that occurs in these disorders. Focal glomerular basement membrane damage was identified in 29 children and was severe in 4 of the children. Alterations included focal and segmental attenuation, splitting, duplications, and spike-like subepithelial protrusions of the lamina densa, along with saccular glomerular microaneurysms arising at the paramesangium. Those cases with extensive glomerular basement membrane lesions had either moderate or severe glomerular alterations apparent by light microscopy. Over half of the cases with glomerular membranopathy had immunohistological or ultrastructural evidence of focal peripheral glomerular capillary wall immune deposits and electron-dense deposits occurred at sites of glomerular basement membrane splitting. Despite the focal attenuation of the glomerular basement membrane, we did not identify any biopsy with findings of thin basement membrane disease. The glomerular basement membrane ultrastructural findings we describe are characteristic of IgA nephropathy and Henoch Schönlein purpura, are common in children with these disorders, and are similar to the ultrastructural alterations of the basement membrane that occur in other glomerulonephritides. These basement membrane injuries may be inflammatory cell or immune mediated but their pathogenesis requires further study.  相似文献   
992.
993.
杜君  雷方 《眼科新进展》2016,(8):777-779
目的 分析Vogt-小柳-原田综合征患者急性期与恢复期黄斑中心凹下方脉络膜厚度(subfovealchoroidalthickness,SFCT)变化。方法 30例Vogt-小柳-原田综合征患者60眼纳入研究,其中男14例,女16例,年龄(45.38±10.19)岁。所有患者均行眼前节检查、最佳矫正视力、眼底彩色照相、眼底血管荧光造影(fundusfluoresceinangiography,FFA)及频域光学相干断层扫描(spectraldomainopticalcoherencetomography,SD-OCT)等检查确诊。经糖皮质激素口服治疗前及治疗2周、6个月、12个月后应用SD-OCT对Vogt-小柳-原田综合征患者进行深度加强扫描(enhanceddepthimaging,EDI)测量SFCT。与正常同龄人群SFCT值进行比较。结果 患眼与正常同龄人群SFCT值(287.85±27.70)μm比较,糖皮质激素治疗前,患眼SFCT厚度(437.46±30.14)μm明显增加,差异有统计学意义(t=3.591,P<0.01)。治疗2周后,患眼SFCT厚度为(352.50±60.37)μm,较治疗前显著下降,差异有统计学意义(t=2.567,P<0.05)。治疗6个月及12个月后,患眼SFCT厚度分别为(299.32±20.12)μm、(297.61±21.89)μm,与正常人群SFCT值比较,差异均无统计学意义(t=1.362、1.272,均为P>0.05)。结论 Vogt-小柳-原田综合征患者急性期SFCT较正常同龄人群明显增厚,恢复期与同龄正常人群比较无明显差别。  相似文献   
994.
We describe the abnormalities seen in the mid periphery and posterior pole of two patients with multifocal vitelliform macular distrophy as evaluated by high-definition spectral domain optical coherence tomography (HD-OCT). In patient 1, HD-OCT scans revealed, in the central area, a thicker and more reflective layer compared with the normal macula, located between the retinal pigment epitelium and the interface of the inner segment /outer segment, corresponding to the Verhoeff‘s membrane. Moreover, HD-OCT macular scans, as well as C-scans, revealed a slight hyper-reflective lesion just above an area of reduced reflectivity between the photoreceptor layer (interface of the inner segment and outer segment) and the Verhoeff‘s membrane. In patient 2, on HD-OCT macular scans, the layer corresponding to the interface of inner segment and outer segment of the photoreceptor, and the Verhoeff's membrane, appeared disrupted, whereas the retinal pigment epithelium layer appeared preserved. On the other hand, in both patient 1 and 2, the clinically evident vitelliform lesions outside the macular area appeared on HD-OCT scans either as small focal hyper-reflective lesions at the level of the retinal pigment epithelium/photoreceptor complex, either as a more pronounced diffuse thickening of the retinal pigment epithelium/photoreceptor complex, facing the deposition of lipofuscin reported on the histopathologic examination. These new findings would help in a further understanding of multifocal vitelliform macular distrophy.  相似文献   
995.
996.
997.
Background: The role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with high-risk (HR) T-cell acute lymphoblastic leukemia (T-ALL) in first complete remission (CR1) is still under evaluation. Moreover, relapse is the main factor affecting survival. This study aimed to explore the effect of allo-HSCT (especially haploidentical HSCT [haplo-HSCT]) on improving survival and reducing relapse for HR childhood T-ALL in CR1 and the prognostic factors of childhood T-ALL in...  相似文献   
998.
Background:In latest decades, mortality rates from ischemic heart disease (IHD) had declined steadily in most of the world as a consequence of improvements in prevention and therapy.Objective:The aim of this study was to analyze trends in mortality caused by IHD in the region of the Americas from 2000 to 2019.Methods:Estimates of the age-adjusted mortality rate (AAMR) due to IHD were extracted from the Data Portal on Noncommunicable Diseases, Mental Health, and External Causes (ENLACE), Pan American Health Organization. We used Joinpoint regression to analyze significant changes in mortality trends by country, gender, geographical sub-region, and country income, according to the World Bank classification. We also calculated the average annual percent change (AAPC) mortality rate for the overall period in the Americas as a whole and by country and sub-region.Results:In the region of the Americas, the AAMR from IHD decreased from 117.80 (95% uncertainty interval (UI)) 106.64–135.90) in 2000 to 73.64 (62.65–92.66) per 100,000 in 2019. In males, from 149.08 (95% UI 138.23–168.08) to 96.02 (95% UI 83.48–117.19) and in females 92.36 (95% UI 81.35–109.42) to 54.84 (95% UI 45.28–71.76). The AAPC mortality rate in the region decreased –2.5% (95% CI: –2.7, –2.3), with joinpoints in 2007 and 2012, –2.3% (95% CI: –2.5, –2.1) in men and –2.7% (95% CI: –3.0, –2.5) in women. According to the sub-region analysis, the highest decrease was recorded in North America, AAPC –3.1% (95% CI: –3.3, –3.0) with one joinpoint in 2011, whereas there was a stagnation of the mortality rate in Central America, Mexico, and Latin Caribbean with an AAPC of 0.1 (–0.2, 0.3) with one joinpoint in 2007.Conclusions:Age-adjusted mortality rate from IHD between 2000 and 2019 has decreased in the region of the Americas. However, different trends were observed, North America had the highest reduction in AAPC, while Central America, Mexico, and Latin Caribbean Region had a stagnation. This trend was highly influenced by country income.  相似文献   
999.
目的:探讨类风湿关节炎(RA)患者合并肺疾病的临床特点。方法:回顾性分析13例RA患者合并肺疾病的临床特点及影像学资料。结果:RA合并肺疾病患者发病年龄偏大,起病急,病情重,病程短,呼吸道症状较轻;疾病活动性,在RA合并肺疾病患者中血小板计数高,血沉(ESR)快,C反应蛋白(CRP)高,并且类风湿因子(RF)呈高滴度阳性;影像学检查,在发现肺部病变时,肺高分辨率CT(HRCT)明显优于普通X线胸片。结论:RA患者合并肺疾病的临床表现多种多样,它的发生与原发病的活动及某些免疫学指标有关,早期行肺HRCT对早期诊断及时治疗非常重要。  相似文献   
1000.
Erythropoietin (EPO) is one of the main cytokines involved in the regulation of erythropoiesis. The main site of EPO production are the kidneys. An altered EPO production leads to pathological conditions such as anemia and polycythaemia. Due to the progressive loss of renal peritubular cells, patients with chronic kidney disease (CKD) have low EPO plasma levels. This decreases erythron stimulation with the direct consequence of developing anemia. Before the introduction in the clinical practice of rHuEpo, in the late 1980s, the only solution for treating this type of anemia were blood transfusions and anabolic steroids. Even rHuEpo has proven to be safe and effective for treatment of anemias, there are some concerns about its cost, the need for frequent parenteral administration, and development of anti-EPO antibodies. These inconveniences prompted the search for novel erythropoiesis stimulating agents. Different strategies lead to isolation or chemical synthesis of such agents as darbepoetin alfa and EPO mimetics. In this review, we present some general aspects of EPO biology, with emphasis on chronic renal failure, and expose some of the alternatives to EPO used for anemia correction.  相似文献   
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