白芨可溶性面膜的制备研究

以白芨为主要原料,开发出了一种新型的可溶性成型面膜,并对其制备工艺进行了研究。结果表明,最佳工艺指标:白芨胶液浓度为6%;甘油添加量为1.5%;面膜厚度为0.20 mm;干燥温度为70℃。该可溶性面膜轻薄、韧性好;天然无刺激、无毒副作用,本身还具有较高美容功能和特别美容疗效;制备工艺简单、成本低、性价比高。     

熊果苷聚乙烯醇面膜治疗黄褐斑的临床观察

目的:观察熊果苷结合高分子化合物聚乙烯醇(Polyvinyl Alcohol,PVA)面膜治疗黄褐斑的临床疗效。方法:48例黄褐斑患者随机分为两组,治疗组24例,外用熊果苷PVA面膜,对照组24例,予vitC导入治疗,一个月为一疗程。结果:熊果苷治疗组有效率为79.2%;高于对照组(20.8%),差异具有统计学意义(x~2=12.34,P<0.01)。未见明显不良反应。结论:熊果苷PVA面膜疗效确切,配制操作简单,便于临床推广使用。     

枯草芽孢杆菌(Bucillus subtilis)所产β-葡聚糖在日化产品中的应用研究

随着绿色、环保等理念的深入人心,天然产物在日化产品中的应用日益受到关注,本文以枯草芽孢杆菌(Bucillus subtilis)所产β-葡聚糖在日化产品中的应用为研究对象,制备了β-葡聚糖面膜、β-葡聚糖精油皂、β-葡聚糖洗发水、β-葡聚糖洗手液4种日用化学品,β-葡聚糖具有增稠、保湿、舒缓肌肤等功效,应用前景广阔。     

表面等离激元共振生物传感器研究整合素蛋白αⅡbβ3与RGD多肽的特异结合

整合素蛋白α_Ⅱbβ₃是血小板上的一种钙依赖性膜受体,其胞外结构域可与含有RGD序列的肽链特异结合.通过将含有NTA-DOGS的磷脂单分子层膜转移到50 nm厚的金膜上,制备了一种含有NTA头部的表面等离激元共振(SPR)传感器敏感膜.设计并合成了含有6个组氨酸和RGD基团的His-tagged短肽P1,并利用SPR生物传感器,对整合素蛋白与含有RGD配基的支撑平面膜的特异相互作用以及Ca²⁺、Mn²⁺对该相互作用的影响进行了研究.结果表明,NTA敏感膜能很好地将P1锚定在支撑平面膜表面,并能够保证P1维持一个有效的定向.将Ca²⁺从低结合位点去除或加入Mn²⁺都能够增加整合素蛋白的配基结合活性.二价阳离子对整合素蛋白配基结合能力的调节作用,可能在整合素发挥其生理功能的过程中具有重要的意义.     

榕树根际土壤广谱拮抗菌株的筛选、鉴定及特性

于江西省吉安市内一株明万历年间植下的古榕树下,采集根际土样并使用23种指示菌通过管碟法和菌丝生长速率法对土壤内放线菌进行拮抗筛选,最终得到一株传代稳定的广谱拮抗菌株AHF-20.根据对菌株的形态观察、生理生化特性以及分子生物学鉴定,将该拮抗菌株鉴定为链霉菌,并对该菌株的抑菌活性物质进行了研究.结果表明:链霉菌AHF-20的发酵产物对23种测试指示菌全部具有拮抗效果,且抑菌能力稳定性较好,对温度、光照、紫外线、酸碱都有一定的耐受性,于121 ℃下加热20 min后依然存在抑菌活性.根据活性物质的极性使用正丁醇萃取发酵产物,获得的正丁醇粗提物稀释至1 μg·mL^-1后,对大肠杆菌仍有抑制效果,可见具有较好的生防利用潜力和开发成新型微生物药物的可能性.     

医疗器械面向使用有计划开办技术推广应用短期学习班

上海市医疗器械工业公司产品技术推广服务部为帮助各级医疗单位,了解产品的结构原理,熟悉操作使用和维修技术,沟通生产和使用之间的联系,听取使用部门的意见,接收质量反馈信息,进一步提高产品质量,为广大医院提供技术装备,积极开展技术服务工作。该公司八○年里组织了七个医疗器械生产工厂,安排举办了人工肾,钴60治疗机,病人监护仪、超声心动图仪、脑电图机,血液自动分析仪,光导纤维胃镜等七种产品的短期技术推广应用学习班。他们的具体做法是,每班一种产品吸收和邀请各级医院临床医生和专职维修人员近百人参加学习。一年来共有600余人参加,学习班邀请具有丰富临床使用经验,造诣较     

表面等离激元共振生物传感器研究整合素蛋白αⅡbβ3与RGD多肽的特异结合

整合素蛋白αⅡbβ3是血小板上的一种钙依赖性膜受体,其胞外结构域可与含有RGD序列的肽链特异结合.通过将含有NTA-DOGS的磷脂单分子层膜转移到50 nm厚的金膜上,制备了一种含有NTA头部的表面等离激元共振(SPR)传感器敏感膜.设计并合成了含有6个组氨酸和RGD基团的His-tagged短肽P1,并利用SPR生物传感器,对整合素蛋白与含有RGD配基的支撑平面膜的特异相互作用以及Ca2+、Mn2+对该相互作用的影响进行了研究.结果表明,NTA敏感膜能很好地将P1锚定在支撑平面膜表面,并能够保证P1维持一个有效的定向.将Ca2+从低结合位点去除或加入Mn2+都能够增加整合素蛋白的配基结合活性.二价阳离子对整合素蛋白配基结合能力的调节作用,可能在整合素发挥其生理功能的过程中具有重要的意义.     

石制品微磨痕分析的实验性研究

以扫描电子显微镜为主要手段,依据Keeley的实验方法,对实验和 “盲测” 的燧石制品进行了微磨痕 (microwear) 的观察分析,验证了该方法的可行性;表明在石制品的加工方式、加工对象与其可能的残留信息——石制品的使用痕迹,如以光泽、条痕、破损疤为主要特征的微磨痕之间所具有的某种实验模式,初步掌握了微磨痕研究的实验方法,取得了一些结果,并予以检验;利用扫描电镜观察 “晶体破损” 与否,可能是鉴定石制品使用或未使用的一种行之有效的方法。     

球孢链霉菌一种抗生素生物合成基因的核苷酸序列分析

C-1027是一种具有极强抗肿瘤活性的新型抗生素,由球孢链霉菌（Streptomycesglobisporus）产生。F2DNA片段含有一种编码C－1027生物合成的基因。以质粒pUC18为载体,对其进行了亚克隆,并对该片段进行了核苷酸序列分析,发现一编码122个氨基酸的开放阅读框架,经检索可能是一种新的序列。     

一款胚芽为核心的八宝粥的营养成分分析及体外活性评价

研究了一款以胚芽为核心的八宝粥的营养成分和抗氧化性能力,以及胚芽球蛋白对RAW 264.7巨噬细胞的增殖作用。首先测定了此款八宝粥的各种氨基酸含量,重点考察了γ-氨基丁酸（GABA）的含量;其次分别采用还原Fe3+、1,1-二苯基-2-三硝基苯肼（DPPH）法、邻苯三酚自氧化法和Folin-Ciocalteu法测定了该产品的总还原力、DPPH自由基清除能力、超氧阴离子自由基清除能力和总多酚的含量;最后分离提取出胚芽球蛋白,并且通过细胞实验分析球蛋白对巨噬细胞的增殖能力。结果表明：该产品氨基酸含量丰富,尤其是GABA含量比较突出,该产品具有很好的抗氧化能力;巨噬细胞的增殖实验表明,该产品具有提高机体的免疫能力的潜力。     

Determinants of skin contact pressure formation during non-invasive ventilation

There is no published data about mask features that impact skin contact pressure during mask ventilation.To investigate the physical factors of skin contact pressure formation.We measured masks with original and reduced air cushion size and recorded contact pressure. We determined cushion contact and mask areas by planimetric measurements.Contact pressures necessary to prevent air leakage during inspiration exceed inspiratory pressure by 1.01±0.41 hPa independent of cushion size.Contact area, ventilator pressure and mask area during inspiration and expiration impact contact pressure. Mask contact pressures are higher during expiration. The contact pressure increases with increase in inspiratory pressures independent of the ventilator cycle. During expiration, the contact pressure will increase in proportion to the expiratory pressure reduction of the ventilator. The mask with reduced air cushion size developed higher contact pressures.Contact pressure can be reduced by selecting masks with a small mask area in combination with a large mask cushion.     

Proseal与Slipa喉罩在腹腔镜胆囊切除术中的麻醉效果比较

目的:比较proseal与slipa喉罩在腹腔镜胆囊切除术中的麻醉效果。方法:收集我院收治的68例胆囊行腹腔镜胆囊切除术患者,随机分为A组和B组,每组各34例,A组患者应用slipa喉罩,B组患者应用proseal喉罩进行麻醉。观察并比较两组患者各时间点血压、心率水平,患者麻醉时间、苏醒时间、喉罩插入时间与拔除时间以及患者的不良反应发生率。结果:与喉罩置入前相比,两组患者手术中收缩压(SBP)以及舒张压(DBP)水平均下降,差异具有统计学意义(P0.05)。两组患者各时间点的血压以、心率、麻醉时间及苏醒时间比较差异均无统计学意义(P0.05)。与B组相比,A组患者的喉罩插入时间较长,喉罩沾血的发生率较高,差异具有统计学意义(P0.05)。结论:Pro seal与Slipa喉罩在腹腔镜胆囊切除术中的麻醉效果相当,但Slipa喉罩的插入时间以及喉罩沾血的发生率更高。     

Exhaled Air Dispersion during Coughing with and without Wearing a Surgical or N95 Mask

Objectives

We compared the expelled air dispersion distances during coughing from a human patient simulator (HPS) lying at 45° with and without wearing a surgical mask or N95 mask in a negative pressure isolation room.

Methods

Airflow was marked with intrapulmonary smoke. Coughing bouts were generated by short bursts of oxygen flow at 650, 320, and 220L/min to simulate normal, mild and poor coughing efforts, respectively. The coughing jet was revealed by laser light-sheet and images were captured by high definition video. Smoke concentration in the plume was estimated from the light scattered by smoke particles. Significant exposure was arbitrarily defined where there was ≥ 20% of normalized smoke concentration.

Results

During normal cough, expelled air dispersion distances were 68, 30 and 15 cm along the median sagittal plane when the HPS wore no mask, a surgical mask and a N95 mask, respectively. In moderate lung injury, the corresponding air dispersion distances for mild coughing efforts were reduced to 55, 27 and 14 cm, respectively, p < 0.001. The distances were reduced to 30, 24 and 12 cm, respectively during poor coughing effort as in severe lung injury. Lateral dispersion distances during normal cough were 0, 28 and 15 cm when the HPS wore no mask, a surgical mask and a N95 mask, respectively.

Conclusions

Normal cough produced a turbulent jet about 0.7 m towards the end of the bed from the recumbent subject. N95 mask was more effective than surgical mask in preventing expelled air leakage during coughing but there was still significant sideway leakage.     

Masking the mask: An Israeli response to the threat of chemical warfare

This paper analyzes a form of visual euphemism which we call “masking the mask.” During the Gulf War, Iraq fired 40 missiles on Israel. Citizens were issued with gas mask kits and were ordered into sealed rooms in their homes during attacks. Thousands of Israelis of all ages decorated or covered their gas mask kits. Although no chemical warheads were fired on the country, Israelis were unusually fearful of gassing because of associations with the Holocaust. Masking the mask served important psychological and communicative functions. It provided a means to express one's fears, to attempt a modest form of mastery over a threatening environment, as well as to rebel against dehumanization and personalization, and to express solidarity with the group under threat, while reasserting one's individual identity.     

Evaluation on masks with exhaust valves and with exhaust holes from physiological and subjective responses

The purpose of this study was to compare the effects of wearing different kinds of masks on the ear canal temperature, heart rate, clothing microclimate, and subjective perception of discomfort. Ten subjects performed intermittent exercise on a treadmill while wearing the protective masks in a climatic chamber controlled at an air temperature of 25 degrees C and a relative humidity of 70%. Two types of mask-mask A, with exhaust valves and mask B, with exhaust holes-were used in the study. The results of this study indicated: (1) The subjects had a tendency toward lower maximum heart rate when wearing mask A than when wearing mask B. (2) Temperatures and absolute humidities (the outer surface of mask, the microclimate inside the mask, the chest wall skin and microclimate) of mask A were significantly lower than those of mask B. (3) The ear canal temperature increased significantly in mask B as compared to that in mask A. (4) The ear canal temperature showed significant augmentation along with increased temperature and humidity inside the mask microclimate. The mask microclimate temperature also affected significantly the chest microclimate temperature. (5) Mask A was rated significantly lower for perception of humidity, heat, breath resistance, tightness, unfitness, odor, fatigue, and offered less overall discomfort than mask B. (6) Subjective preference for mask A was higher. (7) The ratings of subjective overall discomfort showed significant augmentation along with increased wetness and fatigue. We discuss how the ventilation properties of masks A and B induce significantly different temperature and humidity in the microclimates of the masks and the heat loss of the body, which have profound influences on heart rate, thermal stress, and subjective perception of discomfort.     

Alignment of Schlieren and Rayleigh opitcal systems in the ultracentrifuge. 3. Design, construction, and placement of Rayleigh mask

Problems in the optimal design on the double-slit mask used in the adaptation of the Rayleigh interferometer ultracentrifuge are discussed. Consideration is given to the orientation of the mask either symmetrically about a radius or offset with one slit along a radius from the center of rotation, to the placement of the mask above or below the rotor, to the use of a second pair of slits in the cell to mask imperfections in the cell windows, and to certain aberrations arising from variations in the refractive index across the width of the slit and from deviation of light perpendicular to the slits by a component of the radial refractive index gradients. Optimal mask dimensions for different experimental conditions for both symmetrical and offset masks are given. Equations based on the geometry of the cells and mask are derived, permitting calculations sufficient to align correctly a symmetrical mask with minimal labor.     

Use of the laryngeal mask airway in rabbits: placement and efficacy

The laryngeal mask airway (LMA) has been used in various animal species anesthetized for the purpose of device evaluation, but the device has not been evaluated in rabbits during surgery. The authors tested the feasibility and potential advantages of using the LMA in 50 rabbits undergoing surgery under spontaneous-breathing inhalational anesthesia, focusing mainly on the technique of insertion and its efficacy. The LMA was easily inserted and no air leakage at the larynx was detected. Although four rabbits developed lingual cyanosis, this was reversible and most likely due to lingual vascular compression by the LMA. The authors conclude that the LMA is an attractive alternative to endotracheal intubation, as the mask can be inserted easily and rapidly and its correct placement is easily confirmed.     

The Noh mask effect: vertical viewpoint dependence of facial expression perception.

Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences.     

喉罩与气管插管在呼吸衰竭患者院前和急诊急救中的应用效果比较

目的:探讨喉罩与气管插管在呼吸衰竭患者院前和急诊急救中的应用效果。方法:选择2016年1月至2018年5月由中国人民解放军第174医院急诊医学科出诊抢救的呼吸衰竭患者92例,所有患者根据通气方法的不同分为A组和B组。其中A组使用喉罩人工通气方法进行急救,共有47例,而B组则使用气管插管人工通气方法进行急救,共有45例,比较两组患者治疗前与治疗1 h后呼吸频率(RR)、心率(HR)以及血氧饱和度(SpO_2)等生命体征指标,对比喉罩与气管插管置入时间、一次性成功率、心肺复苏成功率情况,记录两组并发症发生情况。结果:两组患者治疗前HR、RR以及SpO_2比较差异无统计学意义(P0.05),两组患者治疗1 h后HR、RR均较治疗前降低,SpO_2较治疗前升高(P0.05),两组患者治疗1h后HR、RR以及SpO_2比较差异无统计学意义(P0.05)。A组的喉罩插管置入时间明显短于B组的气管插管置入时间,且A组插管一次性成功率明显高于B组,两组比较差异具有统计学意义(P0.05),而两组心肺复苏成功率比较差异无统计学意义(P0.05)。A组并发症发生率为2.13%(1/47),低于B组的并发症发生率13.33%(6/45),差异具有统计学意义(P0.05)。结论:喉罩通气与气管插管通气效果基本一致,但其操作更简单更安全,可缩短插管置入时间,提高一次性成功率,争取抢救时间。     

No melatonin suppression by illumination of popliteal fossae or eyelids

A recent report that popliteal illumination shifted the circadian rhythms of body temperature and melatonin challenged the longstanding belief that light phase-shifting the circadian system in mammals is mediated only through the retina. The authors tested effects of popliteal illumination and illumination provided through the eyelids on melatonin suppression. In randomized, counterbalanced orders, healthy volunteers received three treatments from midnight until 2:00 AM, one on each of three visits to the laboratory. Treatments included (1) no illumination from light pads applied to the popliteal fossae, with light mask maintained at < 3 lux (control); (2) light mask illuminated at 1700 lux, with popliteal light pads extinguished; and (3) popliteal light pads illuminated (13,000 lux) and light mask at < 3 lux (control). Saliva specimens were sampled at midnight, at 1:00 AM, and at 2:00 AM. Mean salivary melatonin concentrations rose from an average of 30.8 (3.9) pg/ml at midnight (baseline), to 33.2 (4.0) pg/ml at 1:00 AM, and to 37.2 (3.8) pg/ml at 2:00 AM in all three conditions, but no statistical differences were found using repeated-measures ANOVA. No evidence of melatonin suppression by either popliteal or closed eyelid light stimulation was found. These data suggest that bright retinal illumination is necessary for suppression of melatonin mediated through the suprachiasmatic nuclei.