对硝基甲苯合成对氨基-和对羟基苯申醛

将相转移催化剂用于多硫化钠与对硝基甲苯的还原-氧化反应,合成对氨基苯甲醛(PAB)产率达90%以上。PAB 反应液不经分离直接用于合成对羟基苯甲醛(PHB),产率达90%。考察了影响 PAB 和PHB 产率的各种因素。     

在对的时间,吃对阿司匹林

阿司匹林是世界上历史最悠久的药物之一。早在公元前5世纪,西方医学奠基人之一希波克拉底,就发现柳树皮中存在一种可以止痛和退热的物质。后来,医学界证明,这种物质叫作水杨酸。1859年,随着德国化学家成功合成水杨酸,医生发现水杨酸这边厢止了关节疼痛,那边厢却让胃穿了孔,不得已将它“雪藏”起来。     

你的药店定位对不对？

中国现今的药店,遭遇的困境颇多。处方药的销售在医院的处方难以外流的情况下,没有医生处方难以形成购买;即便构成主要销售的非处方这一块,也将被超市和零售百货瓜分。不久前,在第54届全国药品交易会高峰论坛上,提供O T C医疗健康行业服务的国际咨询公司N H C总裁兼首席执行官NicholasHall称,到2014年,非药店渠道将占据全球50%的OTC销售,届时药店将与超市、零售百货等共同竞争OTC销售市场。据NHC调查统计,尽管全球OTC市场1995年至2005年均保持着2.4%-6%的稳定增长,但日本、德国、法国等市场销售量很大的国家在2005年已出现负增长。…     

脐带绕颈对剖宫产率及对新生儿的影响

目的分析探讨脐带绕颈对剖宫产率及新生儿的影响,提高产妇对脐带绕颈分娩方式的认知度。方法采用回顾性分析方法,有脐带绕颈者为研究组,无脐带绕颈者为对照组,分析两组以社会因素、胎儿窘迫、异常产程及头位异常为手术指征的剖宫产率,比较两组对新生儿窒息的影响及羊水污染情况,比较脐带绕颈周数对剖宫产率的影响。结果两组的剖宫产率、剖宫产的手术指征及对新生儿的影响比较P>0.05,无差异,无统计学意义。脐带绕颈周数两组比较剖宫产率P<0.05,有差异,具有统计学意义。结论对于分娩伴脐带绕颈的孕妇,应消除对脐带绕颈的恐惧心理,合理选择分娩方式,以降低剖宫产率。     

对酚A对雄性小鼠生殖系统的影响

工业时代的到来 ,给人类社会带来了高度的物质文明 ,但也给人类的生存环境带来了种种问题。越来越多的证据表明 ,存在于环境中一些人工合成的化学物质具有体内雌激素的生物效应 ,可以干扰鸟类、爬行类以及哺乳类野生动物或实验动物正常的内分泌功能 ,改变动物在发育和成年阶段胞内信号过程 ,并由此造成动物的雌雄性别的改变以及畸形等病变 ,人们称这类物质为环境雌激素、内分泌干扰剂、内分泌活性化合物或分泌干扰化合物等[1] 。环境雌激素是指一类外源性化合物进入机体后 ,具有干扰体内正常分泌物质的合成、释放、转运、代谢、结合等过程 ,…     

对酪醇对P-糖蛋白功能的影响

目的:研究对酪醇对P-糖蛋白(P-gp)功能的影响.方法:采用环孢霉素A作为P-gP功能抑制的阳性对照,用流式细胞术分析对酪醇对P-gp底物-罗丹明123在Caco-2细胞中外排的影响.结果:当对酪醇浓度在40～160μmol/L时,实验组细胞内荧光强度显著高于阴性对照组(P<0.05),并随着对酪醇浓度的增高而减弱.当浓度在280μmol/L时,实验组细胞内荧光强度与阴性对照组间差异无显著性(P>0.05).当对酪醇浓度为400μmol/L时,实验组细胞内荧光强度更弱显著低于阴性对照组(P<0.05).结论:对酪醇对P-gp功能的影响与浓度有关,低浓度时,对酪醇对P-gp的功能有抑制作用.随着浓度的增高,对酪醇对P-gp的功能的抑制作用减弱.达到一定浓度,对酪醇对P-gp的功能表现出诱导作用.     

对降压药说长道短

目前,临床上使用的抗高血压药物种类繁多,每一类均发挥了重大作用,使诸多高血压患者得到救治,能像正常人一样生活。然而,世上万事万物莫不具有两重性,抗高血压药也不例外,在降压的同时总会出现或轻或重的各种不良反应。     

对改版说几句

我是《家庭医药》的忠实订户,从创刊至今一直订阅。因为身体的原因,医药健康类的报刊订了3份,我的子女们也经常买些杂志回家看,看来看去,就喜欢做些比较。出于对《家庭医药》的喜爱,对读者调查表当中改版方面的问题说两句。     

用对中成药

说是起一服仰用脖中子成一药吞,大口家水都的笑工了夫:嘛这!还不用黄小琥的歌来说,《没那么简单》!作为药剂师,整天看到、接触的是民众使用中成药的种种误区。从选择到使用,还有多少细节没有被民众知晓?为什么会存在这些误区?     

对—羟基苯甲醛和对—羟基苯甲酸对单胺氧化酶活性的影响

小鼠灌服对一羟基苯甲醛(PHBAD)和对一羟基苯甲酸(PHBZA)能明显抑制脑和肝组织的单胺氧化酶(MAO)活性,且对MAO—B的抑制作用强于MAO—A。PHBAD(200～400mg·kg~(-1)对小鼠脑MAO—B抑制作用强于PHBZA。体外实验证明,二者对MAO—B的抑制作用随浓度增加而明显增强。另外,PHBAD对MAO—B呈竞争型抑制;对MAO—A呈混合型抑制;而PHBZA对MAO-B、MAO—A均呈混合型抑制。     

Tetrandrine is not a selective calcium channel blocker in vascular smooth muscle.

The effects of tetrandrine (Tet) on the contractile properties of rat aortic ring preparations were studied to test the hypothesis that Tet is a Ca2+ antagonist acting on voltage-operated Ca2+ channels (VOC). The tests were performed on contractions induced by depolarizing concentrations of KCl and by alpha 1-adrenoceptor agonist, phenylephrine (Phe). These vascular effects of Tet were compared to those of nifedipine (Nif). We found that Tet behaved qualitatively similar to, but less potent than, Nif in that it inhibited KCl-induced contraction in a concentration-dependent fashion and its inhibitory effect was long-lasting. However, the effects on Phe-induced contraction of Tet was different from those of Nif in that the extracellular Ca(2+)-dependent contraction was inhibited by Tet, but not by Nif. Tet (60 mumol.L-1) completely inhibited the 45Ca2+ uptake induced by KCl and Phe in rat aortic muscle strips. When the aortic muscle contractile response was induced by addition of Ca2+ following depletion of intracellular stores by Phe in the presence of sarcoplasmic reticulum Ca(2+)-pump inhibitor, cyclopiazonic acid, Tet (60 mumol.L-1) was more effective than Nif 1 mumol.L-1 in inhibiting such a response to extracellularly added Ca2+. Furthermore, Tet, but not Nif, also significantly inhibited the contraction to Phe in Ca(2+)-free medium. Collectively, these results led us to conclude that Tet does not behave as a selective VOC blocker like Nif.     

莲心碱对几种平滑肌作用的研究

莲心碱（Ｌｉｅ）抑制去氧肾上腺素（ＰＥ），５－羟色胺（５－ＨＴ），组胺（Ｈｉｓ）和高Ｋ＋引起的兔主动脉环收缩，对ＰＥ引起的收缩，其抑制作用更为明显；也抑制ＰＥ所致兔尿道平滑肌的收缩。在兔主动脉环和大鼠肛尾肌标本，Ｌｉｅ使甲氧胺（Ｍｅｔ）及ＰＥ的量效曲线平行右移，最大反应不压低，ＰＡ２值分别为６．８和６．６。Ｌｉｅ还明显抑制去甲肾上腺素（ＮＥ）所致的内钙释放，而对ＮＥ所致外钙内流影响较小。提示：Ｌｉｅ具有阻断肾上腺素α１受体和抑制细胞内钙释放作用。     

淫羊藿甙扩血管作用机制的研究

本实验以离体兔胸主动脉条为标本，对淫羊藿甙（ＥＩ）扩血管作用的机制进行了探讨。ＥＩ２０，４０ｍｇ·Ｌ－１对ＮＥ、ＫＣｌ及ＣａＣｌ２收缩兔主动脉条的量效曲线呈非竞争性拮抗作用；ＥＩ３０ｇ·Ｌ－１能明显抑制ＮＥ诱导的兔主动脉条依赖于细胞外钙的收缩反应，对依赖于细胞内钙的收缩反应没有影响；ＥＩ３０ｇ·Ｌ－１松驰主动脉条的作用与阻断α受体或激动β受体无关。提示ＥＩ的扩血管作用机制可能与其对钙通道的阻滞作用有关。     

Intracellular alkalinization augments alpha(1)-adrenoceptor-mediated vasoconstriction by promotion of Ca(2+) entry through the non-L-type Ca(2+) channels.

Modulation by intracellular pH of the vasoconstriction induced by alpha-adrenoceptor agonists was investigated in isolated guinea pig aorta. NH(4)Cl (15 mM) increased intracellular pH of aortic smooth muscle cells by about 0.2 pH unit and significantly augmented KCl-induced contraction of aortic strips, whereas simultaneous administration of NH(4)Cl (15 mM) plus Na(+) propionate (30 mM) failed to affect intracellular pH or contractility. NH(4)Cl (15 mM) potentiated contractions induced by alpha-adrenoceptor agonists, norepinephrine, phenylephrine and clonidine. Contraction induced by alpha(1)-selective adrenoceptor agonist, phenylephrine, but not that induced by norepinephrine or clonidine, was insensitive to inhibition by verapamil (1 microM). Phenylephrine-induced contraction was not affected by NH(4)Cl in Ca(2+)-free medium whereas extracellular Ca(2+)-induced contraction of phenylephrine-stimulated aorta was significantly augmented by NH(4)Cl. Consistently, 45Ca(2+)uptake into phenylephrine 1 microM)-stimulated aortic strips was increased by incubation with NH(4)Cl. The potentiating effects of NH(4)Cl on both phenylephrine-induced Ca(2+) entry and contraction were antagonized by Na(+) propionate. These results suggest that intracellular alkalinization facilitates alpha(1)-adrenoceptor-mediated vasoconstriction by facilitation of an agonist-induced Ca(2+) entry pathway that is independent of L-type Ca(2+) channels.     

四肽FMRFa对大鼠心室肌Na^＋／Ca^2＋交换的抑制

目的　研究四肽FMRFa对大鼠单个心室肌细胞Na /Ca2 交换的作用。方法　用膜片钳全细胞记录法测定成年大鼠心室肌细胞Na /Ca2 交换电流 (INa /Ca2 )和其他离子通道电流。结果　FMRFa对大鼠心室肌细胞INa /Ca2 呈浓度依赖性抑制 ,10 0 μmol·L-1浓度时抑制内向和外向INa /Ca2 密度分别达 6 0 1%和 5 6 5 % ,对内向电流及外向电流的IC50 分别为 2 0 μmol·L-1和 34μmol·L-1。FMRFa 5 μmol·L-1抑制INa /Ca2 内向和外向电流密度分别为 38 7%和 34 9% ,但FMRFa 5 μmol·L-1及 2 0 μmol·L-1对L型钙电流、钠电流、瞬时外向电流和内向整流钾电流均无显著抑制作用。结论　FMRFa对大鼠心室肌细胞是一个特异性Na /Ca2 交换抑制剂。     

Calcium antagonism of enpiperate on isolated rabbit aorta strips and guinea pig ileum

Enpiperate, 4-(3, 5)-exocydopropyl-N-methylpiperidyl diphenyl hydroxy acetate, was synthesized in China. It has been shown to have no effect on the normal tension of rabbit aorta strips or contractions induced by NE. It inhibited the contraction of high K+-depolarized rabbit aorta strips at concentrations of 3.8 and 10.9 mumol/L. The same effect was seen on isolated guinea pig ileum, at a concentration of 10.9 mumol/L, which was depolarized by Ca2+ free high K+ Locke-Ringer's solution and the contraction was extragenous Ca2+ dependent. The inhibition was overcome by increasing the extracellular Ca2+ concentration. In the presence of EDTA (0.1 mmol/L), the NE induced intracellular Ca2+ dependent contraction was inhibited by enpiperate (3.8, 10.9 mumol/L), although no significant difference was found between enpiperate and papaverine. It is suggested that enpiperate is a calcium antagonist and that the antagonism is carried out by blocking the potential dependent calcium channel (PDC) in the membrane of vascular smooth muscles. A intracellular calcium antagonistic action may also be involved.