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991.
992.
目的 观察白内障超声乳化吸除术联合人工晶体植入术治疗葡萄膜炎并发白内障的临床效果.方法 选取2017年1月-2019年3月本院收治的92例(92只眼)葡萄膜炎并发白内障患者为研究对象,遵循随机对照原则将其分为对照(n=46)和观察组(n=46).对照组行常规小切口白内障囊外切除术联合人工晶体植入术治疗,观察组行白内障超... 相似文献
993.
Weiming Yan Yunpeng Wang Qian Ye Xiaohong Chen Yanjin Chen Chuan Jiang Meizhu Chen 《The Journal of international medical research》2022,50(1)
This case report describes the detailed electrophysiological features and the corresponding relationship with the structural changes in a case of X-linked juvenile retinoschisis (XLRS). A 25-year-old male presented with a history of several years of decreased visual acuity in both eyes. The best corrected visual acuity was 20/200 in oculus dexter (OD) and 20/80 in oculus sinister. Retinoschisis was found in the macula by optical coherence tomography, which was more severe in OD. Electroretinogram revealed a similar electronegative waveform in both eyes. Visual evoked potential detected a reduced amplitude and delayed phase in P100-wave, which was worse in OD. The patient was diagnosed as XLRS and advised to undergo continuous medical observation. He was followed up for the next year, with no significant change in retinal function and structure being observed. These current findings suggest that electrophysiology permits the detailed analysis of the clinical picture of XLRS and helps to gain a deeper understanding of the pathogenesis. 相似文献
994.
995.
Sheridan Goldstein Lupeng Wang Kerry McAlonan Mateus Torres-Cruz Richard J. Krauzlis 《Journal of vision》2022,22(1)
In primates, stimulus-driven changes in visual attention can facilitate or hinder perceptual performance, depending on the location and timing of the stimulus event. Mice have emerged as a powerful model for studying visual circuits and behavior; however, it is unclear whether mice show similar interactions between stimulus events and visual attention during perceptual decisions. To investigate this, we trained head-fixed mice to detect a near-threshold change in visual orientation and tested how performance was altered by task-irrelevant stimuli that occurred at different times and locations with respect to the orientation change. We found that task-irrelevant stimuli strongly affected mouse performance. Specifically, stimulus-driven attention in mice followed a similar time course as that in other species: The decreases in reaction times fully emerged between 250 and 400 ms after the stimulus event, and detection accuracy was not affected. However, the effects of stimulus-driven attention on behavior in mice were insensitive to stimulus-event location, an aspect different from what is known in primates. In contrast, reaction times in mice were reduced at longer delays after the task-irrelevant stimulus event regardless of its spatial congruence to the target. These results highlight the strengths and limitations of using mice as a model for studying higher-order visual functions. 相似文献
996.
高脂高糖、饮酒建立家兔脂肪肝模型及超声量化诊断 总被引:3,自引:0,他引:3
目的:模拟人类不良饮食结构建立家兔不同程度脂肪肝模型,进行肝脏背向散射积分 (integrated backscatter,IBS)和图像灰阶平均强度(gray scale,GS)测定,并结合临床研究,探讨具有病理基础的脂肪肝无创性超声量化诊断标准.方法:选用纯种新西兰家兔40只,采用高脂高糖饲料及乙醇饮料建立不同程度脂肪肝模型三组(每组n=10),设立对照组(n=10):临床病例同步进行肝组织病理学及超声检测.病理组织学检测采用苏丹Ⅳ,HE和Masson三色染色:应用HP Sonos 5500超声诊断仪实时检测肝脏IBS,包括图像平均强度(average image intensity,AII)、峰-峰强度及图像强度标准差; 采用Photo shop 7.0直方图分析超声图像GS.所得数据采用SAS8.2进行统计学分析.结果:肝脏AII随脂肪变加重呈递增趋势,正常肝<轻度脂肪肝<中度脂肪肝<重度脂肪肝,尤以近区各组间差异显著(P<0.0001);同等程度肝脂肪变AII随炎症的发生而增大.临床研究显示,IBS对脂肪肝诊断率及与病理组织学符合率(85.7%)较常规超声检测(57.1%) 明显增高,重度脂肪肝AII显著高于轻度脂肪肝(P<0.0001,0.001或0.05).肝脏GS与AII相关,于肝左、右叶近区二者随病变加重呈一致性增高趋势(r1=0.442 21,P1=0.0012:r2= 0.335 73,P2=0.0160).中重度脂肪肝伴炎症 GS显著高于正常肝及轻度脂肪肝(P<0.05).结论:高营养及乙醇联合喂养家兔可快速建立不同程度脂肪性肝病模型;肝脏超声IBS及 GS强度可反映肝脂肪变、炎症和纤维化的病变程度,为脂肪肝无创性量化诊断提供可靠依据. 相似文献
997.
Ray Taylor Richard Bowen James F. Demarest Michael DeSpirito Airn Hartwig Helle Bielefeldt-Ohmann Dennis M. Walling Amanda Mathis Yarlagadda S. Babu 《Viruses》2022,14(1)
Coronavirus disease 2019 (COVID-19) has claimed the lives of millions of people worldwide since it first emerged. The impact of the COVID-19 pandemic on public health and the global economy has highlighted the medical need for the development of broadly acting interventions against emerging viral threats. Galidesivir is a broad-spectrum antiviral compound with demonstrated in vitro and in vivo efficacy against several RNA viruses of public health concern, including those causing yellow fever, Ebola, Marburg, and Rift Valley fever. In vitro studies have shown that the antiviral activity of galidesivir also extends to coronaviruses. Herein, we describe the efficacy of galidesivir in the Syrian golden hamster model of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Treatment with galidesivir reduced lung pathology in infected animals compared with untreated controls when treatment was initiated 24 h prior to infection. These results add to the evidence of the applicability of galidesivir as a potential medical intervention for a range of acute viral illnesses, including coronaviruses. 相似文献
998.
Tapan K Parikh Jeffrey R Strawn John T Walkup Paul E Croarkin 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2022,25(2):144
BackgroundAnxiety disorders such as generalized anxiety disorder (GAD) impact 10% of the US population, and many patients do not completely respond to first-line treatments (e.g., selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and psychotherapy). Given the dearth of evidence for non-pharmacologic, non-psychotherapeutic interventions, we performed a systematic review and meta-analysis of repetitive transcranial magnetic stimulation (rTMS) in adults with GAD.MethodsA systematic literature review using the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines was conducted. Pre- and post-treatment anxiety scores were extracted, and a random-effects meta-analysis was conducted to determine the magnitude of improvement (standardized mean difference). Standard assessments of heterogeneity (e.g., Q-statistic, I2, and τ 2) and publication bias were performed.ResultsThe initial search resulted in 3194 citations, of which 6 studies were included in the meta-analysis. In total, 152 patients were studied, including 97 patients who received active treatment and 55 who received sham treatment, and heterogeneity was modest (I2 13.32, Q = 5.77). In patients with GAD, rTMS produced a standardized mean difference of −1.857 (confidence interval: −2.219 to −1.494; P < .001) with a prediction interval of −2.55 to −1.16.ConclusionsThe results suggest a robust effect of rTMS in GAD in the context of limited, heterogenous studies. Rigorously designed, randomized controlled trials of rTMS for GAD and related anxiety disorders are urgently needed. These studies will provide opportunities for biomarker development and integration of concurrent evidence-based psychotherapy to maximize results. 相似文献
999.
目的通过检索特殊食品信息查询平台公布的具有缓解视疲劳功能的保健食品信息资料,以及药智数据网的中成药处方数据库中眼科中成药中有保健功能的产品信息资料,为具有缓解视疲劳功能的保健产品的组方与产品开发提供依据与参考。方法运用Microsoft Excel2016软件及中医传承辅助平台对检得的产品信息进行统计,分析其配方特点。结果共收集到141个具有缓解视疲劳功能的保健食品,其中64个(45.4%)保健食品配方中含有中药类原料。使用频次≥5的中药原料有6味,累计使用145次(72%),由高到低分别是菊花、枸杞子、决明子、桑椹、熟地黄、茯苓。通过无监督的熵层次聚类得到3个新处方。非中药原料在缓解视疲劳功能的保健食品中应用较为普遍,含有外来天然植物资源的60个产品,含叶黄素及维生素类的17个。统计眼科中成药中有保健功能的产品可知,使用频次≥4的中药原料有7味,累计使用32次(29%),由高到低分别是枸杞子、决明子、菟丝子、熟地黄、菊花、五味子、车前子。通过无监督的熵层次聚类得到1个新处方。结论保健食品在中药原料的选择上与中医药理论治疗视疲劳的原则基本契合,即滋补肝肾、平肝明目。但二者在中药原料选择范围、原料配伍、剂型种类等方面有所不同。此外,还在辨证保健理论指导下,尝试探讨应用文献数据处理统计方法筛选新配方、开发新产品,为中药复方保健产品的研发开辟了新思路、新方法。 相似文献
1000.
Maindiratta (1990) questioned the usefulness of the concept of scale efficiency in production as the most productive scale size (MPSS) usually requires altering the scale of output produced. If the decision making unit (DMU) is required to deliver a specific output bundle, then altering output along with the input scale to reach the MPSS is not a valid recommendation. He proposed a measure of the size efficiency of a DMU. In this paper, we apply Data Envelopment Analysis (DEA) to examine the levels of technical, scale, and size efficiency of individual nursing homes providing health care to the elderly. The data used relate to the operations of 140 nursing homes from Connecticut, USA during the year 1982–83. Maindiratta's model is input-oriented. By contrast, our study is output-oriented and we appropriately reformulate Maindiratta's model. The findings show that in several cases size efficiency is less than unity. This suggests that the most efficient production of output would require restructuring of the nursing home under investigation as more than one small unit. We also compare the efficiency levels of ‘for-profit’ homes with those of ‘not-for-profit’ homes. 相似文献