数字化口腔内窥镜的设计与实现

以梯度折射率透镜（自聚焦透镜）为摄像镜头，通过光电转换，结合数字信号处理和数据库技术．设计并实现了数字化口腔内窥镜。临床应用表明，所研制的自聚焦口腔内窥镜不仅操作简单、成像清晰且便于对患者的各种信息进行管理、查询，有望成为牙科医生必备的一种新诊疗设备。     

乙型肝炎病毒S基因变异与隐匿性感染的关系

隐匿性HBV感染的存在和临床意义已经被许多研究所证实,目前已有大量研究开始关注其发生机制.此文就HBV的S基因变异对隐匿性感染的发生和影响的若干研究进行综述.     

Analysis on the difference of skin surface lipids during blue light therapy for acne by lipidomics

Acne is a chronic inflammatory skin disease of the sebaceous glands of the hair follicles, caused by a variety of factors and tends to recur, causing skin damage and psychological stress to patients. Blue light (415nm) is a popular physical therapy for acne, however, studies on the effects of blue light on skin surface lipids (SSL) have not been exhaustively reported. So, we want to investigate the difference in SSL before and after acne treatment with blue light and to reveal the potential mechanism of acne treatment with blue light from the lipid level. SSL samples were collected and physiological indicators (moisture content, transepidermal water loss (TEWL), sebum content and pH) were measured. By using ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) with multivariate data analysis methods to obtain specific information on the lipid composition. Analysis of the physiological index data showed a significant increase in moisture content (p = 0.042), pH (p = 0.000) and a significant decrease in sebum content(p = 0.008) in the after treatment area (AT group), while there was no significant change in TEWL values. A total of 2398 lipids were detected by lipidomics analysis and 25 differential lipids were screened. Triradylglycerols (TGs), isoprenoids and hopanoids being the potential differential lipids. Among the lipids associated with the skin barrier, only monounsaturated fatty acids (MUFA) (p = 0.045) were significantly increased. This study revealed significant changes in SSL after blue light treatment for acne, suggesting that blue light exposure may cause changes in the relative lipid content and redistribution of lipid components, and that whether it damages the skin barrier requires further study.     

分次切除在皮肤病损治疗中的应用价值

目的探讨分次切除在皮肤病损治疗中的应用价值。方法通过10年来对498例皮肤病损患者接受分次切除治疗的观察和分析,评估了皮肤病损分次切除的疾病适应证、部位适应证、切口的合理安排和优缺点等。结果所有病例中切除次数为2次的病例457例,治疗时间5~13月,平均(8.06±3.45)月;3次及以上41例,平均(3.12±0.32)次,治疗时间12~21月,平均(13.76±1.34)月。术后随访6~13月,复发5例,其中色素痣3例,疤痕疙瘩2例。色素痣再次手术切除后无复发,疤痕疙瘩采取切除加放疗后无复发。结论分次切除在较大面积及特殊部位的皮肤病灶切除术中有其特有的优点和临床应用价值。     

雌孕激素对乳腺癌MCF-7细胞热休克蛋白mRNA水平的影响

目的：研究一定浓度雌、孕激素作用于MCF-7细胞一定时间后,细胞中VEGF、Hsp70、Hsp90和NF-κBp50 mRNA水平上的变化,进而揭示雌、孕激素对乳腺癌MCF-7细胞株作用的分子生物学机制.方法：体外培养人乳腺癌MCF-7细胞株,分4组给予不同处理因素,分别为对照组、雌激素组、孕激素组和雌孕激素混合组.给药72 h后MTT法测细胞570 nm分光光度值.RT-PCR法观察各组Hsp70、Hsp90、VEGF和NF-κBp50 mRNA表达水平.结果：与对照组相比,10^-9mol/L雌激素促进细胞生长作用最明显,10-7mol/L孕激素本身对MCF^-7细胞生长无明显影响,但在雌、孕激素混合组孕激素部分抑制雌激素促细胞增殖作用,具有统计学意义.与对照组相比,雌激素上调细胞中Hsp70、Hsp90、VEGF和NF-κBp50 mRNA水平;孕激素组Hsp70、Hsp90、VEGF和NF-κBp50 mRNA水平与对照组差异无统计学意义.孕激素可以部分抑制雌激素对MCF-7细胞Hsp70、Hsp90、VEGF和NF-κBp50 mRNA的上调作用.结论：雌激素促进乳腺癌细胞生长,可能是雌激素与癌细胞受体结合后通过某种途径刺激Hsp70、Hsp90、NF-κBp50及VEGF的表达,进而抑制癌细胞的凋亡,促进细胞增殖.孕激素通过抑制雌激素对Hsp70、Hsp90、NF-κBp50和 VEGF mRNA的上调作用,进而抑制其促进细胞增殖作用.雌、孕激素促进或抑制细胞增殖,与其对Hsp70、Hsp90、NF-κBp50及VEGF基因的调控是密切相关的.     

Short-Term Visual Experience Leads to Potentiation of Spontaneous Activity in Mouse Superior Colliculus

Spontaneous activity in the brain maintains an internal structured pattern that reflects the external environment,which is essential for processing information and developing perception and cognition.An essential prerequisite of spontaneous activity for perception is the ability to reverberate external information,such as by potentiation.Yet its role in the processing of potentiation in mouse superior colliculus(SC)neurons is less studied.Here,we used electrophysiological recording,optogenetics,and drug infusion methods to investigate the mechanism of potentiation in SC neurons.We found that visual experience potentiated SC neurons several minutes later in different developmental stages,and the similarity between spontaneous and visually-evoked activity increased with age.Before eye-opening,activation of retinal ganglion cells that expressed ChR2 also induced the potentiation of spontaneous activity in the mouse SC.Potentiation was dependenton stimulus number and showed feature selectivity for direction and orientation.Optogenetic activation of parvalbumin neurons in the SC attenuated the potentiation induced by visual experience.Furthermore,potentiation in SC neurons was blocked by inhibiting the glutamate transporter GLT1.These results indicated that the potentiation induced by a visual stimulus might play a key role in shaping the internal representation of the environment,and serves as a carrier for short-term memory consolidation.     

Predictions and Experiments on the Distortion of the 20Cr2Ni4A C-ring during Carburizing and Quenching Process

This paper focuses on the effect of gear steel on distortion due to phase transformation in carburizing and quenching. The carburizing and quenching process of C-rings under suspension was studied by using the finite element method based on the thermo-mechanical theory, considering phase transformation. The phase transformation kinetics parameters, depending on different carbon contents, were measured by Gleeble-3500. The distortion behavior of the carburized C-ring during the cooling stage was analyzed, as well as the carbon concentration distribution and martensite volume fractions. The accuracy of the simulation was also verified by comparing the experimental data with the simulated result of the distortion and microstructure. A reliable basis is provided for predicting the distortion mechanism of gear steels in carburizing and quenching.     

长春胺对非动脉炎性前部缺血性视神经病变大鼠模型视神经保护作用及其机制

目的：研究长春胺对非动脉炎性前部缺血性视神经病变（NAION）大鼠模型的潜在神经保护作用。方法：90只SD大鼠随机分为正常组、单纯模型组、造模羧甲基纤维素钠灌胃组（NaCMC)组、长春胺组、造模PI3K抑制剂LY294002玻璃体腔注射(IVT LY)+长春胺组、造模DMSO玻璃体腔注射（IVT DMSO)+长春胺组。对各组进行眼底照相,眼底荧光血管造影,血清一氧化氮（NO）浓度检测,HE染色观察视网膜形态,甲苯胺蓝染色观察视神经轴突形态,免疫荧光染色计数视网膜神经节细胞（RGCs）,实时定量PCR检测p-AKT、eNOS含量。结果：rNAION大鼠（rNAION）造模成功后第1天即可见大鼠视盘水肿,边界模糊。造模后第28天,长春胺组的NO浓度显著高于正常对照组、单纯模型组及NaCMC组。与单纯模型组相比,长春胺组RGCs数量明显增加（P<0.05）,pAKT、eNOS含量明显增加（P<0.05）。IVT LY+长春胺组RGCs数量及p-AKT、eNOS含量较长春胺组明显减少（P<0.05）。结论：长春胺可能通过PI3K/AKT/eNOS信号通路发挥视神经保护作用,有...     

Consumption of Dietary Fiber with Different Physicochemical Properties during Late Pregnancy Alters the Gut Microbiota and Relieves Constipation in Sow Model

Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers.