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目的 制备抗柯萨奇病毒A组2型( coxsackievirus A2,CV-A2)单克隆抗体(单抗),建立CV-A2抗原检测方法。方法 用纯化后的CV-A2全病毒颗粒免疫小鼠,筛选获得抗CV-A2单抗。建立CV-A2抗原检测方法,确定线性范围,对其准确度、精密度、稳定性、专属性进行验证。用 ELISA检测病毒颗粒纯化过程中样品的抗原含量。结果 制备了高效价的抗CV-A2单抗并建立 ELISA抗原检测方法,检测范围为5.00~320.00 ng/ml。高、中、低3个浓度样品准确度验证回收率在89.58%~104.78%之间。重复性验证变异系数分别为2.10%、2.47%、6.18%。中间精密度验证变异系数分别为2.89%、2.69%、1.94%。耐用性验证回收率在84.26%~114.21%之间。包被微孔板于37℃放置3d,样品回收率在90.31%~103.11%之间。专属性验证结果显示该方法只识别CV-A2抗原,与其他抗原均无交叉反应。结论 建立并验证了CV-A2 ELISA抗原检测方法,可应用于病毒纯化过程中样品的抗原检测,还可应用于含CV-A2的手足口病多价疫苗的CV-A2抗原含量检测。 相似文献
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234.
Xia Fengjie Lyu Jiao Peng Jie Zhao Peiquan 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2022,260(9):2837-2846
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the retinal vascularization of repeated intravitreal ranibizumab (IVR) for reactivated retinopathy of prematurity... 相似文献
235.
AIM:To explore the efficacy of the orthokeratology lens for anisometropic myopia progression.METHODS:A retrospective study was performed.Cycloplegic refraction and axial length(AL)were collected from 50 children(10.52±1.72 y)who visited Peking University Third Hospital from July 2015 to August 2020.These children’s one eyes(Group A)received monocular orthokeratology lenses at first,after different durations(12.20±6.94 mo),their contralateral eyes(Group B)developed myopia and receive orthokeratology as well.The data in 1-year of binocular period were recorded.AL growth rate(difference of follow-up and baseline per month)were compared between two groups by paired t test.Interocular differences of AL were compared by Wilcoxon test.RESULTS:During monocular period,the AL growth rate of the Group A(0.008±0.022 mm/mo)was significantly slower than that of the Group B(0.038±0.018 mm/mo;P<0.0001).However,during binocular period,the AL growth rate of the Group A(0.026±0.014 mm/mo)was significantly faster than that of the Group B(0.016±0.015 mm/mo;P<0.0001).The AL difference between both eyes was 0.6(0.46)mm,then significantly decreased to 0.22(0.39)mm when started binocular treatment(P<0.0001).However,it was significantly increased to 0.30(0.32)mm after a year(P<0.0001),but still significantly lower than baseline(P<0.0001).CONCLUSION:The orthokeratology lens is efficient for control the AL elongation of monocular myopia eyes and reduce anisometropia.For the condition that the contralateral eyes develop myopia and receive orthokeratology lens later,there is no efficiency observed on control interocular difference of AL during binocular treatment. 相似文献
236.
Analysis of retinal vasculature changes in indirect traumatic optic neuropathy using optic coherence tomography angiography 下载免费PDF全文
Huan M Yang Gao Jin-Miao Li Yue-Kun Bao Cong Nie Pan Yin Xi Lyu Xiao-Yan Ding Rong Lu 《国际眼科》2022,15(8):1344-1351
AIM: To assess the retinal vasculature alterations in indirect traumatic optic neuropathy (ITON) patients following craniofacial trauma by optic coherence tomography angiography (OCTA).
METHODS: Patients diagnosed of monocular ITON were recruited from August 2016 to May 2020. OCTA was performed using the AngioVue OCT-A system for two cube scans centered at the optic nerve head and fovea. OCTA data included thicknesses of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC), as well as proportion of capillary perfusion and data were analyzed for correlation with post-injury timepoints: within 7, 8-30, 31-90, and 91-365d.
RESULTS: A total of 73 ITON patients were studied. Significant thinning of RNFL and GCC layers and attenuation of microvascular perfusion were observed in ITON eyes as compared to contralateral unaffected eyes (for most of the analyzed sectors and quadrants, P<0.05). Without respect to surgical intervention and vision recovery, the decrease in retinal layer thicknesses and microvascular perfusion was time-dependent, and most significant within three months (P<0.001).
CONCLUSION: ITON presents with time-dependent thinning of retinal layers and attenuation of microvasculature, indicating possible degeneration of retinal ganglion cells due to reduced retinal blood supply. 相似文献
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238.
Antiphospholipid syndrome (APS) is identified as the presence of antiphospholipid antibodies (aPLs) in patients with vascular thrombosis and/or pregnancy morbidity (including fetal death, premature birth and habitual abortion). Neurological manifestations in patients with APS are common, whereas movement disorders are rarely seen. We report an extremely rare case of APS presented with parkinsonism and review the literature to address the clinical profile and possible pathophysiologic mechanism of this disorder. 相似文献
239.
The purpose of this study was to review the clinical manifestations of 40 patients who fulfilled the clinical criteria for Hirayama disease (juvenile muscular atrophy of distal upper extremities), identified in our neuromuscular clinic between February 1995 and December 2005. Of these 40 patients, 87.5% were male. The mean age at onset was 16.8 years, which was 4.5 years later than the peak age of the normal growth curve. Progressive muscle weakness and wasting were characteristic and occurred predominantly in the distal part of the right upper limb. Neurogenic symptoms ceased to progress within 5 years in most patients (92.5%). About one third of patients had participated frequently in heavy physical activity before onset of muscle symptoms. Reduced amplitude of the compound muscle action potential of the ulnar nerve was the most prominent finding in nerve conduction studies. Electromyography showed acute or chronic neurogenic changes, most frequently in muscles supplied by the C7-T1 segments. Magnetic resonance imaging showed anterior shifting of the posterior dura and engorged posterior venous plexus at the cervical level in 95% of patients. Our results support the belief that Hirayama disease is a self-limited, focal lower motor neuron disease involving the lower cervical segments. Disproportionate growth between the vertebral column and the contents of the spinal canal may be the underlying cause, and strenuous physical activity may be a precipitating factor. 相似文献
240.
Taku Fujimura Aya Kakizaki Yumi Kambayashi Yota Sato Kayo Tanita Chunbing Lyu Sadanori Furudate Setsuya Aiba 《Experimental dermatology》2018,27(1):64-70
Together with regulatory T cells (Tregs), tumor‐associated macrophages (TAMs) play roles in maintaining the tumor microenvironment. Although cytotoxic antimelanoma drugs such as dacarbazine (DTIC), nimustine hydrochloride (ACNU) and vincristine (VCR) have been used for the treatment of malignant melanoma as adjuvant therapy in Japan, the detailed mechanisms of their immunomodulatory effects are not fully understood. As the majority of TAMs are alternatively activated M2 macrophages that favour tumor development, the aim of this study was to elucidate the immunomodulatory effects of these reagents on human monocyte‐derived M2 macrophages. First, mRNA expressions and protein production of immune checkpoint molecules, PD‐L1 and chemokines by CD163+ CD206+ M2 macrophages derived from peripheral blood mononuclear cells were investigated to determine the immunomodulatory effects of DTIC, ACNU, and VCR. DTIC and VCR significantly decreased PD‐L1 mRNA expression, which was confirmed by flow cytometry. Moreover, the mRNA expression and production of CCL22 were significantly decreased by DTIC, which suggested that DTIC might suppress the recruitment of Tregs in the tumor site. Furthermore, the decreased expression of PD‐L1 and production of CCL22 were validated in vivo, using the B16F10 mouse melanoma model, leading to abrogation of the suppressive function of T‐cell proliferation. The present report suggests one of the possible antimelanoma mechanisms of DAV combination chemotherapy for melanoma patients. 相似文献