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91.
为了探讨突触素(SYN)在不同周龄阶段胎儿端脑额叶中的表达与胎儿额叶皮质突触发育的关系,本研究采用免疫组织化学方法观察突触素在不同周龄阶段胎儿额叶的表达水平,利用计算机图像分析技术测量不同周龄阶段胎儿额叶突触素表达的平均光密度;同时取材、常规电镜技术处理、透射电镜观察额叶突触发育的超微结构变化。结果显示:(1)光镜下各组均可见SYN免疫阳性产物主要表达于胎儿的额叶皮层,其表达量随周龄的增加而增强,各组间呈现显著性差异(P<0.05),其中16~24周胎儿额叶的阳性产物位于神经元的胞浆内,呈均匀的浅黄色,神经元突起内未见阳性产物;25~29周额叶的阳性产物呈黄色,在胞浆和突起内均可见,但阳性产物的量却下降;而30~39周额叶的SYN阳性产物呈棕黄色的点状或颗粒状,主要位于神经元的突起内,神经元胞浆内未见阳性产物,阳性产物的量显著增加;(2)透射电镜下19~36周胎儿大脑额叶均可见到突触样结构,随着周龄的增加,突触的数量逐渐增多,结构逐渐清晰和完整。上述结果提示SYN的表达可以反映胎儿神经系统发育的程度,SYN的表达与突触的发育是一致的;SYN在胎儿大脑额叶的表达部位经历由神经元胞浆内表达为主到神经元终末表达为主的这一过程,可能是由于SYN先是在神经元胞浆内合成,再随着神经元的发育而逐步转移到神经元突起的末梢部位。 相似文献
92.
植物化感作用及其在中药材栽培中的应用 总被引:1,自引:0,他引:1
本文介绍了目前植物化感作用的研究领域及其进展,包括化感物质的收集、分离和鉴定,化感物质作用机理以及影响化感作用的因素等方面,分析了药用植物化感作用较为严重的原因以及在栽培过程中追求药材质量的同时很可能会加剧其化感作用的特点,并且从栽培措施、化感育种以及改善土壤微生态环境等几个方面提出了有效利用和克服药用植物化感作用的措施,旨在为中药材规范化种植提供理论和方法依据。 相似文献
93.
94.
Rationale:Femtosecond laser-assisted cataract surgery (FLACS) has grown in popularity among ophthalmologists as a novel surgical technique. However, malignant glaucoma (MG) is a complication of FLACS. Herein, we report a case of MG following FLACS.Patient concerns:A 66-year-old woman presented with complaints of blurred vision in the right eye and a foreign body sensation in both eyes. Ophthalmological examinations showed that the corrected distance visual acuity was 20/50 and 20/25 in the right and left eyes, respectively. Without any topical anti-glaucoma medication, the intraocular pressure (IOP) was 20 mmHg in the right eye and 17 mmHg in the left eye. Slit-lamp examination of the right eye revealed a transparent cornea with a defect in the punctate overlying epithelium; the central anterior chamber depth was shallow the peripheral iris laser shot was visible, the pupil was normal, and the lens was mainly cortical opacified.Diagnoses:Based on the patient''s symptoms, examination results, and preliminary diagnoses, age-related cataract in the right eye, binocular post-antiglaucoma surgery, pseudophakicin in the left eye, and Sjogren syndrome were included.Interventions:FLACS was performed to facilitate anterior capsulotomy and segmentation of the nucleus in the right eye. MG occurred after the femtosecond procedure, and with the treatment of medicines combined with phacoemulsification, IOP was eventually normal without further antiglaucoma therapy.Outcomes:IOP was 16 mmHg on postoperative day 1. Ocular ultrasonography revealed no choroid detachment or hemorrhage in the right eye. Two weeks postoperatively, uncorrected visual acuity was 20/25, and IOP remained normal with no further antiglaucoma treatment on 1 month postoperatively.Conclusions:We describe the occurrence of MG after FLACS and illustrate that miosis and bubble formation after FLACS may be risk factors for MG during FLACS. 相似文献
95.
Gongbo Zeng Dong Chen Renxi Zhou Xinfeng Zhao Cuiying Ye Huiting Tao Wenbin Sheng Yidong Wu 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundAlthough early diagnosis and management are critical for prognosis of pediatric sepsis, there are no specific diagnostic biomarkers for the hyperinflammatory state and organ dysfunction, important stages of sepsis.MethodsWe enrolled 129 children with infection into three groups: non‐sepsis infection (33), Sepsis 1.0 (hyperinflammatory state, 67), and Sepsis 3.0 (organ dysfunction, 29). Another 32 children with no infections were included as controls. Serum C‐reactive protein (CRP), procalcitonin (PCT), interleukin (IL)‐1β, IL‐2, IL‐4, IL‐5, IL‐6, IL‐8, IL‐10, IL‐12p70, IL‐17, tumor necrosis factor (TNF)‐α, interferon (IFN)‐α, and IFN‐γ were assessed to diagnose the two stages, and their diagnostic capacities were evaluated using receiver operating characteristic (ROC) curves. We also examined whether combining biomarkers improved diagnostic efficiency.ResultsSignificantly higher CRP, PCT, and IL‐6 levels were detected in the Sepsis 1.0 than the non‐sepsis infection group (p < 0.001). The areas under the curve (AUCs) for diagnosing Sepsis 1.0 were 0.974 (CRP), 0.913 (PCT) and 0.919 (IL‐6). A combination of any two biomarkers increased diagnostic sensitivity to ≥92.54% and specificity to 100.00%. Significantly higher PCT, IL‐8, and IL‐10 levels were found in the Sepsis 3.0 than the Sepsis 1.0 group (p ≤ 0.01), with AUCs for diagnosing Sepsis 3.0 0.807 (PCT), 0.711 (IL‐8), and 0.860 (IL‐10). Combining these three biomarkers increased diagnostic sensitivity to 96.55% and specificity to 94.03%.ConclusionIn pediatric sepsis, combining any two of CRP, PCT, and IL‐6 can accurately diagnose the hyperinflammatory state and increase diagnostic specificity. Early diagnosis of organ dysfunction requires a combination of PCT, IL‐8, and IL‐10. 相似文献
96.
Xiurong Zhu Lousia J. Hope-Weeks Yi Yu Jvjun Yuan Xianke Zhang Huajun Yu Jiajun Liu Xiaofen Li Xianghua Zeng 《RSC advances》2022,12(31):20191
By using glycidol as a catalyst, high porosity, low-density resorcinol (R) and formaldehyde (F) aerogels and carbon aerogels (CAs) were synthesized via a sol-gel method. The effect of glycidol and water on the color, density, morphology, textual characteristics and adsorption properties of the resultant RF aerogels and CAs were investigated in detail. The results revealed that the properties of RF aerogels and CAs can be controlled by adjusting the amount of glycidol and water. The resultant RF aerogels and CAs were porous materials, the minimum densities of RF aerogels and CAs were 96 and 110 mg cm−3 respectively while the maximum specific surface areas of RF aerogels and CAs were 290 and 597 m2 g−1. The maximum adsorption capacity of CAs was about 125 mg g−1 on Rhodamine B, which was higher than that of some reported CAs catalyzed by base and acid catalysts. The sol-gel mechanisms of RF aerogels and CAs can be attributed to the opening of the epoxy group of glycidol in the mixture of R and F.The sol-gel mechanism of glycidol-catalyzed RF aerogels is the opening of the epoxy ring rather than the preservation the of epoxy ring. 相似文献
97.
Zheng Chen Xifeng Hu Xiangdong Wu Yu Li Zhen Ding Qinghua Zeng Tong Wan Jingyi Yin Huansheng Wu 《Viruses》2022,14(7)
Porcine circovirus-like virus (PCLV) is a member of circovirus that contains a single-strand DNA genome, which may be one of the pathogens that causes diarrheal symptoms in pigs. The Rep protein encoded by the genome of PCLV may be responsible for viral genome replication. The development of serological detection methods for PCLV is of great necessity for clinical diagnosis, as well as epidemiological investigations. Therefore, this study attempted to build an indirect enzyme-linked immunosorbent assay (ELISA) to examine antibodies against PCLV based on the His-tagged recombinant Rep protein. Full-length PCLV Rep protein was induced and expressed in E. coli and was purified as an antigen to establish an ELISA detection kit. The purified Rep protein was used to inject into mice to produce specific antibodies. There was no cross-reaction of Rep-based ELISA with antisera against other porcine viruses. The intra-assay and inter-assay coefficient variations (CVs) were 0.644–8.211% and 0.859–7.246%, respectively, indicating good repeatability. The non-cross-reaction with TGEV, PRRSV and PCV2 testing showed high sensitivity and high specificity for this ELISA assay. A total of 1593 serum samples collected from different pig farms in Jiangxi Province were tested for anti-PCLV Rep antibodies, and 284 (17.83%) of the 1593 samples were Rep antibody positive. Altogether, the indirect ELISA detection tool developed in this study could be applied to examine serum of PCLV antibodies with good repeatability, high sensitivity and high specificity. In addition, field sample detection results suggested that the PCLV antibody has a low prevalence in pig populations in Jiangxi Province of China. 相似文献
98.
99.
蜂海绵Haliclonasp.化学成分的研究 总被引:5,自引:2,他引:5
对采自我罱海的蜂海绵Haliclomasp.的化学成分进行了研究。结果表明:从Haliclonasp.中分离出2个结晶性化合物1和2。应用波谱分析和元素分析鉴定1和2的结构分别为1,3-二甲基黄嘌呤和对羟基苯甲酸。这是从海绵中分离出上述化合物的首次报道。 相似文献
100.
目的:探讨甲硝唑、维生素B2、珍珠粉等配伍治疗口腔溃疡的疗效.方法:选取200例于2014年6月1日~2016年6月1日我院接收的复发性口腔溃疡患者,随机分为对照组(给予西瓜霜喷剂治疗,n=100)与观察组(采用甲硝唑、维生素B2、珍珠粉等配伍治疗,n=100),观察两组疗效.结果:治疗7d后,观察组临床总有效率较对照组显著要高(P<0.05),复发率显著低于对照组(P<0.05);观察组疼痛感消除时间、溃疡治愈时间均较对照组显著要短(P<0.05);治疗后,两组外周血CD4+、CD4+/CD8+水平明显升高,观察组升高幅度较对照组显著(P<0.05).结论:复发性口腔溃疡采取甲硝唑、维生素B2、珍珠粉、山茶油配伍治疗,疗效显著,具有推广价值. 相似文献