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1.
Cassava, corn, high amylose corn, potato, rice Indica, rice Japonica, sweet potato, waxy corn, and wheat starches were exposed to low-pressure ammonia, hydrogen, and oxygen plasma. In every case, depolymerization of the starch polysaccharides was noted. The extent of the depolymerization depended on the nature of the starch as well as the type of plasma applied. Among three fractions of polysaccharides distinguished by their molecular weight average, the fraction of the highest molecular weight suffered the most efficient depolymerization. The relative depolymerization for the middle- and low-molecular fractions of polysaccharides was found to be starch and plasma specific. The chemical character of the plasma had very little influence on the starch polysaccharides. Only subtle oxidation effects were observed in oxygen plasma. Low-pressure glow plasma treatment appeared to be a convenient tool for a waste-less dextrinization of starch. Manipulation of the plasma variety and the time of exposure resulted in a wide spectrum of dextrins of various molecular weights and paste-forming properties.  相似文献   

2.
文章对眼组织细胞内的激光等离子体诱导蚀除的发展现状、物理机理及未来趋势做了综合评述,并从理论上解释了眼组织内等离子体的屏蔽机制,同时提出了更有效蚀除即把副作用降低到最低限度的解决办法。  相似文献   

3.
Appraisal of hepatic lipase and lipoprotein lipase activities in mice   总被引:1,自引:0,他引:1  
A variety of methods are currently used to analyze HL and LPL activities in mice. In search of a simple methodology, we analyzed mouse preheparin and postheparin plasma LPL and HL activities using specific polyclonal antibodies raised in rabbit against rat HL (anti-HL) and in goat against rat LPL (anti-LPL). As an alternative, we analyzed HL activity in the presence of 1 M NaCl, a condition known to inhibit LPL activity in humans. The assays were validated using plasma samples from wild-type and HL-deficient C57BL/6 mice. We now show that the use of 1 M NaCl for the inhibition of plasma LPL activity in mice may generate incorrect measurements of both LPL and HL activities. Our data indicate that HL can be measured directly, without heparin injection, in preheparin plasma, because virtually all HL is present in an unbound form circulating in plasma. In contrast, measurable LPL activity is present only in postheparin plasma. Both HL and LPL can be measured using the same assay conditions (low salt and the presence of apolipoprotein C-II as an LPL activator). Total lipase activity in postheparin plasma minus preheparin HL activity reflects LPL activity. Specific antibodies are not required.  相似文献   

4.
脐血浆治疗大鼠实验性肝衰竭及其机制的研究   总被引:2,自引:0,他引:2  
本文采用脐血浆治疗实验性肝衰竭大鼠模型,并与成人血浆的疗效进行了比较。结果表明,脐血浆降低大鼠死亡率、血谷丙转氨酶水平,总胆红素浓度及使甲胎蛋白水平升高均明显高于成人血浆的作用(P<0.05).肝脏病理组织学也显示脐血浆具有减轻病理损害和较快修复坏死组织的作用。提示脐血浆中含有促进肝细胞再生的因子,具有显著提高实验性大鼠肝衰竭的存活率。  相似文献   

5.
6.
This movie shows how an atmospheric pressure plasma torch can be ignited by microwave power with no additional igniters. After ignition of the plasma, a stable and continuous operation of the plasma is possible and the plasma torch can be used for many different applications. On one hand, the hot (3,600 K gas temperature) plasma can be used for chemical processes and on the other hand the cold afterglow (temperatures down to almost RT) can be applied for surface processes. For example chemical syntheses are interesting volume processes. Here the microwave plasma torch can be used for the decomposition of waste gases which are harmful and contribute to the global warming but are needed as etching gases in growing industry sectors like the semiconductor branch. Another application is the dissociation of CO2. Surplus electrical energy from renewable energy sources can be used to dissociate CO2 to CO and O2. The CO can be further processed to gaseous or liquid higher hydrocarbons thereby providing chemical storage of the energy, synthetic fuels or platform chemicals for the chemical industry. Applications of the afterglow of the plasma torch are the treatment of surfaces to increase the adhesion of lacquer, glue or paint, and the sterilization or decontamination of different kind of surfaces. The movie will explain how to ignite the plasma solely by microwave power without any additional igniters, e.g., electric sparks. The microwave plasma torch is based on a combination of two resonators — a coaxial one which provides the ignition of the plasma and a cylindrical one which guarantees a continuous and stable operation of the plasma after ignition. The plasma can be operated in a long microwave transparent tube for volume processes or shaped by orifices for surface treatment purposes.  相似文献   

7.
8.
Osei-Kumah A  Smith R  Clifton VL 《Cytokine》2008,43(2):187-193
The mechanisms contributing to worsening of asthma during pregnancy have not been well characterized. Both asthma and pregnancy are conditions associated with a skewing of the immune response from T helper (Th) 1 toward a Th2 response. We hypothesise that worsening of asthma during pregnancy may be due to an enhanced production of circulating proinflammatory cytokines and chemokines and this may be modified by the use of inhaled glucocorticoid treatment. Peripheral blood was collected from asthmatic (n = 35) and control non-asthmatic patients (n = 13) in the third trimester (30–37 weeks) of pregnancy. Fetal blood was collected from the umbilical vein of the placenta after delivery from normal (n = 24) and pregnancies complicated by asthma (n = 24). Plasma samples were assayed for IL-6, -8, eotaxin and RANTES using conventional ELISA. In addition, a range of Th1 and Th2 cytokines measured using Luminex system. There were no significant differences in the levels of maternal IL-6, IL-8, eotaxin and RANTES between asthmatics and nonasthmatics. The results of this study suggest that the presence of asthma does not result in an enhanced circulation of Th2 related cytokines and chemokines during the third trimester of pregnancy. Furthermore peripheral blood cytokine concentrations appear unaffected by inhaled glucocorticoid treatment. Cord plasma eotaxin concentrations were increased in pregnancies complicated by asthma, compared with control. This is the first study to show increased eotaxin production in the feto-placental unit of asthmatic pregnancies and may be one mechanism by which allergy susceptibility is increased in the offspring of asthmatic women.  相似文献   

9.
We isolated the major protein of apparent Mr of 15,000–16,000 from seminal plasma as well as from seminal veiscle secretion of bull and proved by amino acid analysis and tryptic peptide mapping that the two proteins were identical. An antiserum against this major protein was employed to quantitate and identify the major protein in seminal plasma as well as seminal vesicle secretion. The antiserum did not cross-react with proteins from bovine or human plasma or follicular fluid respectively.Cell-free translation of poly(A)RNA from seminal vesicle tissue and immunoprecipitation yielded one major species with apparent Mr of 18,000. Using the anti-major protein antiserum, this major species was specifically immuno absorbed. Cloning and sequencing of a major protein-specific cDNA led to the identification of clone pMP17, encoding a precursor of the major protein of 128 amino acid residues. We proved that the major protein is identical to protein PDC 109 (Eschet al., Biochem. Biophys. Res. Comm. 113:861–867, 1983).The seminal vesicles synthesize major protein in an androgen-dependent fashion. In addition to intraluminal secretion of the vas deferens, ampullary spermatozoa revealed an intense immunoreaction which was restricted to the neck region of the sperm head and the middle piece, while the principal piece of the tail as well as the sperm head were devoid of immunoreactive material. Epididymal epithelium (as well as calf seminal vesicle epithelium) showed no immunoreactivity with major protein antiserum. Immunoelectron microscopy demonstrated that only spermatozoa devoid of a plasma membrane around the middle piece were able to bind the antiserum against major protein. After removal of the plasma membrane from epididymal spermatozoa, binding of major protein to subplasmalemmal binding sites was visualised using gold-labeled MP.Transblotting with gold-labeled MP demonstrated a protein of about 66 kDa which appears to represent the major protein-receptor. Binding of major protein to the receptor (after loss of the plasma membrane in the mid-piece region of the spermatozoa after contact with secretions from seminal vesicles) is interpreted as a phyisological process presumably related to the onset of sperm motility.  相似文献   

10.
Plasma zinc, copper, and parameters of growth were measured in a group of 116 French preschool children, 2–5 yr-old from low-income households. Participants were selected on the basis of Z-scores of weight for height (WHZ) and height for age (HAZ). Zinc and copper concentrations of children with growth impairment (GI), defined by a WHZ and/or HAZ< −1 Z-score, were compared to those of age, sex, and ethnic origin matched controls (WHZ and HAZ >−1 Z-score). Mean (±SD) plasma zinc concentration was 12.58±1.84 μmol/L in the GI group, and 13.27±1.98 μmol/L in the controls. The difference of the means of paired samples was 0.69±2.34, and by pairedt-test the significance reachedp=0.028. This effect was primarily a result of the weight retarded group (WHZ <−1 Z-score,p<0.009) and to the girls (p<0.05). There were no significant differences in plasma copper concentrations between groups. These results suggest the presence of marginal zinc deficiency in French preschool children with low weight for height Z-scores.  相似文献   

11.
Vasoactive intestinal polypeptide (VIP) has been proposed as the neurotransmitter of the atropine-resistant relaxation of gastric structures in the lamb. To examine this proposal VIP concentrations in plasma from arterial, gastric venous and intestinal venous blood were measured in healthy conscious lambs before, during and after teasing with, and sucking of milk. Basal arterial plasma VIP concentrations were undetectable (less than 3 pmol/l) and remained so during and after feeding. Before feeding VIP was detected in only 2 of 12 gastric venous plasma samples (5 and 13 pmol/l). During teasing with food there were increments in VIP of 19 +/- 4 pmol/l and during feeding of 27 +/- 5 pmol/l. VIP concentration in gastric venous plasma rapidly returned to fasting levels after cessation of sucking. In contrast VIP in the intestinal venous plasma did not rise during teasing or upon commencement of sucking but a peak increment of 34 +/- 6 pmol/l occurred at 5 min after cessation of feeding. The results are consistent with the hypotheses that VIP is released in anticipation of and during sucking from inhibitory neurones involved in relaxation of gastric structures and that intestinal release of VIP is a consequence of entry of digesta into the small intestine.  相似文献   

12.
目的:研究单采血浆中两种耗材-管路和贮存袋,材料和方法:以压力监测器接头(DPM)、导管流量和贮存袋耐寒性的研究关键。并与国内外同类产品或材料作比较,结果:DPM必须具有适宜的透气性(感应时间≤2s)、阻血性(能耐受40Kpa,40s),滤除率(0.5um粒子,≥90%),导管流量的准确性(与机器设定值误差<5%),稳定性(采集过程中流量误差<5%)可通过控制导管内径(3.08-3.24mm)和选择弹性PVC材料来解决,贮存袋选用耐寒PVC料。扫描电镜证实韧性断裂。结论:研制成的管路和PCS^2机器适配能取代进口同类产品,研制的贮存袋能低温保存血浆,破损率小于2‰。  相似文献   

13.
Cold atmospheric‐pressure plasmas have become of increasing importance in sterilization processes especially with the growing prevalence of multi‐resistant bacteria. Albeit the potential for technological application is obvious, much less is known about the molecular mechanisms underlying bacterial inactivation. X‐jet technology separates plasma‐generated reactive particles and photons, thus allowing the investigation of their individual and joint effects on DNA. Raman spectroscopy shows that particles and photons cause different modifications in DNA single and double strands. The treatment with the combination of particles and photons does not only result in cumulative, but in synergistic effects. Profilometry confirms that etching is a minor contributor to the observed DNA damage in vitro.

Schematics of DNA oligomer treatment with cold atmospheric‐pressure plasma.  相似文献   


14.
This experimental research aimed to investigate the effects of non-thermal plasma on nerve regeneration after transected nerve damage using the sciatic nerve in Wistar albino (A) rats. The experiments were performed on 27 Wistar A rats. The rats underwent surgery for right sciatic nerve exposure and were divided into three groups (each group, n = 9) according to sciatic nerve transected injury (SNTI) and non-thermal plasma application: a non-nerve damage (non-ND) group, a only nerve damage without non-thermal plasma application (ND) group, and a nerve damage with non-thermal plasma application (ND + NTP) group. Subsequent to SNTI and immediate suture, non-thermal plasma was administered three times per week for eight weeks. Evaluation for functional recovery was performed using the static sciatic index measured over the full treatment period of eight weeks. The sciatic nerve specimens were obtained after euthanasia and third day from the last non-thermal plasma application. The sciatic nerve tissues were subjected to histological analysis. Behavior analysis presented that the ND + NTP group showed improved static sciatic index compared with the nerve damage group. Histopathological findings demonstrated that the ND + NTP group had more dense Schwann cells and well-established continuity of nerve fibers, greater than the nerve damage group. Immunohistochemistry showed that the ND + NTP group had increased levels of markers for microtubule-associated protein 2 (MAP2), tau, S100 calcium-binding protein B, and neurofilament-200 and regulated the overexpression of CD68 and MAP2. These results indicated that non-thermal plasma enhanced the motor function and restored the neuronal structure by accelerating myelination and axonal regeneration. Additionally, non-thermal plasma was confirmed to have a positive effect on the recovery of SNTI in rats.  相似文献   

15.
Abstract

We examined whether soybean (SB) and soy protein isolate (SPI) can prevent the betaine-induced elevation of plasma cholesterol as well as maintain the betaine-induced reduction of plasma Hcy concentration. Rats were fed casein-, SB-, or SPI-based diet with or without betaine; SPI-based diet with betaine containing soybean fiber (SF) or soy lecithin (SL) or the combination of SF and SL. Plasma Hcy concentration was decreased by feeding betaine to rats fed the casein-, SB-, and SPI-based diets. Betaine-induced elevation of plasma cholesterol was decreased by feeding the SB-based diet compared with the casein-based diet, but was not decreased by feeding the SPI-based diet. In rats fed the SPI-based diet, the increased concentration of plasma cholesterol by betaine feeding was not prevented by independent addition of SL or SF, but was prevented by a combination of SL and SF, and was associated with increased fecal excretion of bile acids.  相似文献   

16.
The removal of biofilm is a prerequisite for a successful treatment of biofilm‐associated diseases. In this study, we compared the feasibility of an atmospheric pressure plasma device with a sonic powered brush to remove naturally grown supragingival biofilm from extracted teeth. Twenty‐four periodontally hopeless teeth were extracted. Argon jet plasma with an oxygen admixture of 1 vol% and a sonically driven brush were used to remove biofilm with application times of 60 s, 180 s and 300 s. The treatment efficiency was assessed with light microscopy, scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The highest biofilm removal rate was observed after an application time of 180 s/300 s with the sonic brush (80.4%/86.2%), plasma (75.5%/89.0%). These observations were confirmed by SEM. According to XPS analysis, plasma treatment decreased the amount of carbon and nitrogen, indicative of an extensive removal of proteins. Plasma treatment of naturally grown biofilm resulted in an effective cleaning of the tooth surface and was comparable to mechanical treatment. Treatment time had a significant influence on plaque reduction. These results showed that plasma could be a useful adjuvant treatment modality in cases where biofilm removal or reduction plays a decisive role, such as periodontitis and peri‐implantitis.

Plasma‐treated biofilm on an extracted tooth.  相似文献   


17.
Summary Plasma membrane vesicles were prepared from Ehrlich cells using two-phase system compartmentation. The highly pure plasma membrane vesicles obtained presented a negligible mitochondrial contamination and were suitable for studies of amino acid transport.l-Serine transport showed a clear ionic specificity, maximum incorporation being observed when an inwardly directed NaSCN gradient was used. Na+-dependentl-serine transport was dependent on assay temperature and membrane potential, and it seemed to be carried out by two different transport systems. An essential sulfhydryl group seemed to be involved in the transport process.  相似文献   

18.
李之珍  胡晓武  许霞  杨飞  孙晓祥 《生物磁学》2011,(21):4123-4125
目的:探讨糖化血红蛋白(HbAlc)与糖尿病诊断、疗效评价及并发症的关系。方法:选择2型糖尿病患者250例和健康体检者150例,分别测定空腹血糖(FPG)、2h血糖(2hPG)及糖化血红蛋白(HbAlc),统计学分析HbAlc与FPG、2hPG的相关性;分析HbAlc与糖尿病并发症发生的关系。结果:糖尿病组FPG、2hPG及HbAlc水平均显著高于对照组(P〈0.01);糖尿病伴有并发症患者的HbAlc明显高于无并发症者(P〈0.05),HbAlc水平与糖尿病并发症的发生率存在高度相关性(P〈0.01)。结论:检测外周血中HbAlc水平对2型糖尿病诊断、疗效评价具有重要,临床价值,控制糖化血红蛋白对预防糖尿病并发症的发生具有重要意义。  相似文献   

19.
The aim of this study was to investigate the effect of strenuous exercise on plasma nitric oxide and iron (PI) concentrations in rats. The rats were divided into six groups: 3, 6 and 12 months of the exercise (swimming) groups and their corresponding controls. At the end of experimental periods, blood samples were collected to measure plasma NOx (nitrate and nitrite) and iron concentrations and other hematological indices. The correlative analysis of plasma NOx with PI in the exercised and the control rats was performed. The results showed that plasma NOx concentration was significantly greater and PI lower in the 3, 6, and 12 months of the exercise groups compared to their sedentary controls (p < 0.01). However, the duration of strenuous exercise had no significant effect on plasma NOx or PI contents. A negative correlation between plasma NOx and PI levels was found in all three exercise groups (r = -0.750, -0.578, and -0.808 and p < 0.01, 0.05, 0.01 respectively), but not in the sedentary control groups. These results imply that strenuous exercise may lead to an increase in plasma NOx concentration as well as a low iron level. They also suggest the possibility that the increased NO production might be associated with the development of the lower iron status in exercise.  相似文献   

20.
摘要 目的:探讨双重血浆分子吸附术(DPMAS)联合低置换量血浆置换术(LPE)与全量血浆置换术(PE)治疗肝衰竭的临床疗效差异。方法:回顾性分析2019年6月至2020年10月在空军军医大学第二附属医院感染科治疗的101例肝衰竭患者的临床资料,分为双重血浆分子吸附联合低置换量血浆置换术(DPMAS+ LPE)治疗组51例和全量血浆置换术(PE)治疗组50例。对首次治疗前及治疗后24 h的肝功能、凝血系列、血小板等实验室指标、不良反应等进行对比分析。结果:DPMAS+LPE组与PE组治疗后两组血清总胆红素(TBIL)、谷丙转氨酶(ALT)、谷草转氨酶(AST)较治疗前均明显下降(P<0.05),DPMAS+LPE组对胆红素清除效果优于PE组,两组TBIL下降率分别为36.5±17.1% vs 25.2±19.5%,差异有统计学意义(P<0.01)。DPMAS+LPE组治疗后凝血酶原时间(PT)、凝血酶原活动度(PTA)、活化部分凝血活酶时间(APTT)较治疗前无明显变化(P>0.05),纤维蛋白原(FIB)、血浆白蛋白(ALB)较前有所降低(P<0.0001),PE组治疗后PT、PTA、APTT较治疗前有所改善(P<0.05),纤维蛋白原(FIB)、血浆白蛋白(ALB)较治疗前无明显变化(P>0.05)。两组血小板计数(PLT)较治疗前均有所降低(P<0.05),但两组PLT下降率无统计学意义(P>0.05)。两组治疗中及治疗后均未见明显不良反应。结论:双重血浆分子吸附联合低置换量血浆置换术,与全量血浆置换术比较,不仅在清除血清胆红素方面更有优势,且对凝血功能无明显影响,无明显不良反应,可节约血浆用量,是治疗肝衰竭有效、安全的方式,值得推广。  相似文献   

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