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31.
黄芪种子萌发特性的研究   总被引:22,自引:4,他引:18  
运用室内测定方法,对黄芪野生种子和栽培种子的吸不率及其不同处理下的种子发芽率进行了比较试验,结果表明,采用砂磨方法可使黄芪种子的萌发率明显高于其它方法,黄芪各子种皮的机械抵制是导致发芽率低的直接原因;黄芪种子在23℃/15℃变温度条件一的萌发率;不同采收期也会通过影响种子的成熟度而影响发芽率。  相似文献   
32.
目的:观察步长稳心颗粒(简称稳心颗粒)治疗功能性早搏的临床疗效及安全性。方法:选择功能性早搏60例病人,随机分为治疗组及对照组,每组各30例。治疗组给予稳心颗粒一包(9克),每日三次,温开水冲服;对照组给予倍他乐克25毫克,每日二次口服,一个月为一疗程。结果:四周后治疗组显效11例,有效16例,总有效率90%。对照组显效8例,有效18例,总有效率86.7%,p>0.05,两组比较无显著性差异。对血压、心率影响方面稳心颗粒明显优于倍他乐克结论:稳心颗粒治疗功能性早搏疗效显著,且效果稳定,安全无明显不良反应,值得临床推广应用。  相似文献   
33.
Aim:  To determine the critical component(s) of skim milk for biofilm formation of Cronobacter species.
Methods and Results:  Biofilm forming ability of 72 Cronobacter strains in skim milk preparation was assayed by crystal violet staining. The results revealed that whey protein and casein are more important determinants of skim milk for biofilm formation than lactose, although there was a wide variation in biofilm forming ability. Biofilm structure and capsular material of six strains exhibiting different biofilm forming ability was investigated via electron microscopes. Scanning electron microscopy showed visually that while the strong biofilm formers (E27B, FSM 30 and 2·82) resulted in almost complete coagulation of skim milk, the weak biofilm formers (55, FSM 290 and 2·84) caused less coagulation. No capsule was clearly delineated in transmission electron micrographs of either strong or weak biofilm formers.
Conclusion:  These results indicate that, for biofilm formation of Cronobacter species in skim milk, nitrogen source is probably a more important determinant than carbohydrate, and that strong biofilm formers are responsible for substantial coagulation of skim milk.
Significance and Impact of the Study:  This study provides information for better understanding of the underlying mechanisms by which Cronobacter species form biofilm in infant formula milk.  相似文献   
34.
目的探讨乳杆菌活菌胶囊辅助治疗妊娠期外阴阴道假丝酵母菌病疗效观察。方法选取妊娠期外阴阴道假丝酵母菌病患者70例,采用随机数字表将纳入患者分为观察组35例和对照组35例。观察组患者予以乳杆菌活菌胶囊联合制菌素阴道栓治疗,对照组予以单纯的制菌素阴道栓治疗,均连用10d。两组患者停药2周后进行临床疗效观察,并比较治疗后随访3个月的复发率。结果治疗后停药2周,观察组患者的临床总有效率(91.43%)明显优于对照组(71.43%)(χ2=4.63,P〈0.05);治疗后随访观察3个月,对照组复发11例(44.00%),观察组复发5例(15.63%),观察组患者复发率明显低于对照组(χ2=5.60,P〈0.05)。结论乳杆菌活菌胶囊辅助治疗妊娠期外阴阴道假丝酵母菌病疗效好,复发率低,对外阴阴道假丝酵母菌病具有治疗和预防复发的双重功效。  相似文献   
35.
为了建立天麻胶囊中主要有效成分天麻素的快速鉴定方法,根据天麻素的理化特性,使用乙醇和甲醇提取天麻胶囊中的天麻素,使用薄层色谱法进行鉴定,并与高效液相色谱法的分析结果进行比较。结果表明,薄层色谱法的鉴定结果与高效液相色谱法的检测结果一致,能较准确地鉴别天麻胶囊的真伪。本研究结果表明薄层色谱法能快速简便、准确灵敏地检测天麻胶囊中的有效成分,可作为法定鉴定方法的补充,对天麻胶囊实施快速初筛。  相似文献   
36.
Klebsiella pneumoniae is an opportunistic pathogen, which causes a wide range of nosocomial infections. Recently, antibiotic resistance makes K. pneumoniae infection difficult to deal with. Investigation on virulence determinants of K. pneumoniae can provide more information about pathogenesis and unveil new targets for treatment or vaccine development. In this study, SitA, a Fur-regulated divalent cation transporter, was found significantly increased when K. pneumoniae was cultured in a nutrient-limited condition. A sitA-deletion strain (ΔsitA) was created to characterize the importance of SitA in virulence. ΔsitA showed higher sensitivity toward hydroperoxide than its parental strain. In a mouse intraperitoneal infection model, the survival rate of mice infected with ΔsitA strain increased greatly when compared with that of mice infected with the parental strain, suggesting that sitA deletion attenuates the bacterial virulence in vivo. To test whether ΔsitA strain is a potential vaccine candidate, mice were immunized with inactivated bacteria and then challenged with the wild-type strain. The results showed that using ΔsitA mutant protected mice better than using the wild-type strain or the capsule-negative congenic bacteria. In summary, SitA was found being important for the growth of K. pneumoniae in vivo and deleting sitA might be a potential approach to generate vaccines against K. pneumoniae.  相似文献   
37.
Sunfish rodlet cells were examined in vitro using a novel tissue explant system. Outgrowth of epidermal cell layers from explanted fish scales enabled both live cell videomicroscopy and immunocytochemical analysis of rodlet cells within the cell layer. Cells stained with fluorescent phallotoxin and antibody to tubulin showed that F‐actin is a component of the fibrous capsule that envelopes the cell and a microtubule network extends from the basal to apical ends of the cell interior. The fibrous capsule is also enriched for phosphotyrosine suggesting a potential signal‐transducing capability is present in this structure. Videomicroscopy analysis of live explant cultures demonstrated that rodlet cells are immobile and that interior structures are highly dynamic. Rodlet sacs can undergo extension and retraction, while intracellular particles can move rapidly within these cells. Fish scale tissue explants provide a useful system for analyzing the molecular composition and dynamic behavior of rodlet cells.  相似文献   
38.
A highly selective assay was developed for screening compounds that bind to the porcine recombinant β2-adrenoceptor (β2-AR) with affinity chromatography coupled to quadrupole time-of-flight mass spectrometry (Q-TOF–MS). The methodology involved selective screening with immobilized β2-AR, a highly accurate identification via Q-TOF–MS, and a functional evaluation of the screened compounds with a sensitive myograph system. Ferulic acid, hydroxysafflor yellow A (HSYA), and naringin were confirmed to be the bioactive compounds in Huoxue capsule that specifically bound to the β2-AR. These compounds produced a concentration-dependent relaxation of arteries that were contracted by treatment with phenylephrine, and the relaxation caused by these compounds was attenuated in the presence of ICI 118551, a type of β2-AR antagonist. Our data indicate that the use of an immobilized receptor is potentially an alternative method for the rapid screening of bioactive compounds in a complex matrix because of its high specificity. β2-AR affinity chromatography was valuable in focusing attention on the further investigation of ferulic acid, HSYA, and naringin as β2-AR agonists.  相似文献   
39.
Since the early 1950s, more than one hundred cyanobacterial strains,belonging to twenty different genera, have been investigated with regard tothe production and the released exocellular polysaccharides (RPS) into theculture medium. The chemical and rheological properties show that suchpolysaccharides are complex anionic heteropolymers, in about 80% casescontaining six to ten different monosaccharides and in about 90% casescontaining one or more uronic acids; almost all have non-saccharidiccomponents, such as peptidic moieties, acetyl, pyruvyl and/or sulphategroups. Based on such ingredients, cyanobacterial RPSs show promise asthickening or suspending agents, emulsifying or cation-chelating compoundsand the residual capsulated cyanobacterial biomass, following RPSextraction, could be an effective cation-chelating material. Indeed, wheneleven unicellular and filamentous RPS-producing cyanobacteria, selectedon the basis of the anion density of their RPSs and on the abundance oftheir outermost investments, were screened for their ability to removeCu2+ from aqueous solutions, a quick and most effective heavy metaladsorption was observed for the unicellular Cyanothece CE 4 and thefilamentous Cyanospira capsulata. These results suggest the possibilityto accomplish, through the exploitation of RPS-producing cyanobacteria,a multiproduct strategy to procure a wide range of biopolymers suited tovarious industrial applications, in addition to the residual biomass effectivein the recovery of heavy metals from polluted waters.  相似文献   
40.
摘要 目的:探讨肾康注射液联合羟苯磺酸钙胶囊对原发性肾病综合征(PNS)并发急性肾损伤(AKI)患者肾功能、凝血功能及炎性因子的影响。方法:选取2018年4月~2019年11月期间我院收治的134例PNS合并AKI患者,随机分为对照组(常规治疗基础上予以羟苯磺酸钙胶囊治疗)和联合组(对照组基础上予以肾康注射液治疗),各67例。治疗14 d后,对比两组患者疗效、肾功能指标[尿素氮(BUN)、血肌酐(Scr)、白蛋白(Alb)]、凝血功能指标[凝血酶时间(TT)、凝血酶原时间(PT)、活化部分凝血酶原时间(APTT)、纤维蛋白原(FIB)]及炎性因子[白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)],记录两组不良反应情况。结果:联合组治疗14d后的临床总有效率高于对照组(P<0.05)。治疗14 d后,两组PT、APTT、TT、FIB、Scr、BUN、IL-6、TNF-α、CRP均较治疗前下降,且联合组低于对照组(P<0.05)。治疗14 d后,两组Alb升高,且联合组高于对照组(P<0.05)。对照组、联合组的不良反应总发生率对比未见统计学差异(P>0.05)。结论:相较于羟苯磺酸钙胶囊单药治疗,PNS合并AKI患者在羟苯磺酸钙胶囊的基础上联合肾康注射液治疗,可有效减轻肾功能损害,改善凝血功能,降低炎性因子水平,疗效明显,且未增加严重不良反应。  相似文献   
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