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851.
Jinyi Yuan Biwen Mo Zhuang Ma Yuan Lv Shih-Lung Cheng Yanping Yang Zhaohui Tong Renguang Wu Shenghua Sun Zhaolong Cao Jufang Wu Demei Zhu Liwen Chang Yingyuan Zhang 《Journal of microbiology, immunology, and infection》2019,52(1):35-44
Background/Purpose
Nemonoxacin is a novel nonfluorinated quinolone with excellent in vitro activity against most pathogens in community-acquired pneumonia (CAP), especially Gram-positive isolates. The purpose of this study was to assess the efficacy and safety of nemonoxacin compared with levofloxacin in patients with CAP.Methods
A phase 3, multicenter, randomized (2:1) controlled trial was conducted in adult CAP patients receiving nemonoxacin 500 mg or levofloxacin 500 mg orally once daily for 7–10 days. Clinical, microbiological response and adverse events were assessed. Non-inferiority was determined in terms of clinical cure rate of nemonoxacin compared with that of levofloxacin in a modified intention-to-treat (mITT) population. NCT registration number: NCT01529476.Results
A total of 527 patients were randomized and treated with nemonoxacin (n = 356) or levofloxacin (n = 171). The clinical cure rate at test-of-cure visit was 94.3% (300/318) for nemonoxacin and 93.5% (143/153) for levofloxacin in the mITT population [difference (95% CI), 0.9% (?3.8%, 5.5%)]. The microbiological success rate was 92.1% (105/114) for nemonoxacin and 91.7% (55/60) for levofloxacin in the bacteriological mITT population [difference (95% CI), 0.4% (?8.1%, 9.0%)]. The incidence of adverse events (AEs) was comparable between nemonoxacin (33.1%, 118/356) and levofloxacin (33.3%, 57/171) (P > 0.05).Conclusion
Nemonoxacin 500 mg once daily for 7–10 days is as effective and safe as levofloxacin for treating adult CAP patients in terms of clinical cure rates, microbiological success rates, and safety profile.ClinicalTrials.gov identifier: NCT01529476. 相似文献852.
853.
白纹伊蚊和埃及伊蚊defensin A基因克隆及序列分析 总被引:5,自引:0,他引:5
应用PCR技术从白纹伊蚊和埃及伊蚊基因组中扩增出defensinA基因 ,并与文献报道的defensinA的5个型的cDNA序列进行同源性比较 ,发现此两序列中存在内元 ;从埃及伊蚊体内扩增的片段为蚊虫defen sinAl的前体AaDefAl;从白纹伊蚊体内扩增的片段为defensinA的 1个新型 ,命名为DefA6。 相似文献
854.
Pancreatic hormone amylin and integrity of the gastric mucosa 总被引:1,自引:0,他引:1
German SV Zhuĭkova SE Komarov FI Kopylova GN Kuper GJ Luk'iantseva GV Samonina GE Smirnova EA Umarova BA 《Vestnik Rossi?sko? akademii meditsinskikh nauk / Rossi?skaia akademiia meditsinskikh nauk》2001,(12):34-38
The paper presents experimental findings of some possible mechanisms of protective antiulcerous action of amyline. Amyline is the second beta-cell pancreatic hormone, which has been just recently discovered. The authors have studied the effects of amyline on gastric secretion, mast cell functions, mesenteric lymphatic microvascular contractility, i.e. on individual aggressive and protective factors of the gastric mucosa. Amyline has been found to inhibit basal acid gastric secretion and the secretion stimulated by vagal irritation. The peptide reduces the secretory activities of mast cells. Amyline given to animals increases the heparin saturation index of mast cells and decreases the degranulation index. Amyline-induced stabilization of mast cells appears to followed by the decreased release of histamine and other damaging substances. The stimulating effect of amyline on the contractile activity of mesenteric lymphatic vessels was recorded in rats. Amyline increases both the frequency and amplitude of their contractions. The increased lymph flow that is closely associated with microcirculation promotes the maintenance of tissue homeostasis. Therefore, the protective antiulcerous properties of amyline reduce the action of aggressive agents on the gastric mucosa and stimulate protective ones. 相似文献
855.
应用电脑对111例儿童哮喘50项指标进行多因素逐步回归分析,把发作时喘憋严重,平时也有不同程度的喘息症状患儿列入小儿重症哮喘,与非重症哮喘比较,结果显示夜间喘、急性发作持续天数、非特异性刺激诱发、间歇期症状、发绀、呼吸困难、入院后激素治疗、中性粒细胞、IgA、pH、哮喘持续状态等11个因素入选重症哮喘回归方程,表明这些因素与小儿重症哮喘相关,提出儿童哮喘危险信号的临床指标。 相似文献
856.
在神经元干细胞的图像分析中,准确快速的图像分割是干细胞分化增值自动追踪系统的基础。为了准确地分割低对比度的灰度神经元干细胞图像,本研究提出一种基于形态学运算和均值平移算法的神经元干细胞分割方法,称其为形态学的均值平移算法。此算法可以快速地获得任意形状细胞的图像,并且能检测到图像中多连接边缘不封闭的细胞。将此方法应用于神经元干细胞序列图像分割中并且将其与门限分割、水线分割和活动轮廓进行对比。实验结果证明,与其它的方法相比,此方法获得的细胞分割形状更接近于真实细胞的形状,并且能获得或接近于原始图像中准确的独立细胞数目。此方法可以获得正确的分割结果,为进一步图像处理奠定了良好的基础。 相似文献
857.
小鼠室旁核内雌激素受体与催产素、加压素表达的免疫组化研究 总被引:1,自引:2,他引:1
目的研究雌激素的核受体ER-α和ER-β以及催产素、加压素在成年雌性小鼠下丘脑室旁核内的表达。方法采用硫酸镍铵增强显色的免疫组化SP法检测ER-α、ER-β、催产素和加压素在室旁核内的表达。结果雌激素的两种核受体在室旁核内都有表达,但是以ER-β为主(P〈0.001),其免疫阳性产物均在细胞核内,未见核外免疫阳性反应。催产素的免疫阳性产物主要在细胞核周围的胞浆即核周质内,而加压素的免疫阳性物质除了在核周质内有很强的反应外,在突起内也可见很强的免疫反应。ER-α的免疫阳性胞体主要在大细胞部内侧,而ER-β、催产素和加压素的免疫阳性胞体主要在背侧帽部或大细胞部的外侧。结论室旁核内两种雌激素受体可能都参与了对催产素和加压素的调节,但ER-β可能发挥了主要的调节作用。 相似文献
858.
目的观察休克淋巴液对大鼠肠系膜微淋巴管内皮细胞(MMLEC)培养上清液中自由基、NO、TNFα、IL-6的影响,探讨休克淋巴液损伤MMLEC的体液机制。方法正常大鼠MMLEC进行原代培养,应用第三代MMLEC进行本研究。无菌条件下复制大鼠重症失血性休克模型(血压40mm—Hg,维持90min),引流休克时肠系膜淋巴液及门静脉血。以4%终浓度的休克淋巴液直接作用于MMLEC6h,同时以休克血浆、正常淋巴液、正常血浆、胎牛血清(FBS)、DMEM培养液作为对照;检测上清液中MDA、NO、TNFα、IL-6的变化。结果4%终浓度的休克淋巴液作用6h后,培养上清液MDA、NO、TNFα及IL--6含量均显著高于正常淋巴液组、休克血浆组、正常血浆组、FBS组以及DMEM组;而休克血浆作用MMLEC6h后MDA、NO及IL--6含量显著高于正常淋巴液组、正常血浆组、FBS组和DMEM组;其它组间无统计学差异。结论休克淋巴液诱导大鼠MMLEC损伤的体液机制与休克淋巴液诱导MMLEC自由基损伤、促进炎症介质释放有关。 相似文献
859.
Alan Ma Sunita Gurnasinghani Edwin P. Kirk Conor McClenaghan Gautam K. Singh Dorothy K. Grange Chetan Pandit Yung Zhu Tony Roscioli George Elakis Michael Buckley Bhavesh Mehta Philip Roberts Jonathan Mervis Andrew Biggin Colin G. Nichols 《American journal of medical genetics. Part A》2019,179(8):1585-1590
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS. 相似文献
860.
目的:观察正常真皮内的单核-巨噬细胞和树枝状细胞的分布、排列规律,探讨单核-巨噬细胞在皮肤免疫防御中的作用。方法:正常皮肤8例,取面部、躯干、四肢近端、四肢远端、手掌和足跖6个部位皮肤,进行纵行与水平切片。CD1a和CD68单克隆抗体染色,观察朗格汉斯细胞(LC)和单核.巨噬细胞的分布形态和密度。结果:真皮浅层CD68阳性细胞呈网状分布,其密度为361-562个/mm^2。真皮内血管周围及附属器周围亦见CD68阳性细胞。真皮深层CD68阳性细胞多为树枝状,散在分布于粗大的胶原纤维之间。不同解剖部位真皮浅层CD68阳性细胞密度分别为:四肢远端562个/mm^2,腹部517个/mm^2,面部509个/mm^2,手掌507个/mm^2,四肢近端472个/mm^2,足跖361个/mm^2。真皮浅层CD68阳性细胞在手掌和足跖部位高于相应部位的表皮内CD1a和CD68细胞。结论:在真皮浅层形成数层单核.巨噬细胞网,此网在接近真表皮交界处较致密。真皮内单核-巨噬细胞的这种分布形式说明这些细胞在真皮内有明确的方向性,其防御的方向是穿透表皮进入真皮的入侵物。 相似文献