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991.
目的 观察普济宣肺消毒饮对急性支气管炎化痰作用.方法 用随机、对照、前瞻性研究方法,将87例急性支气管炎(表寒里热证)患者随机分为治疗组44例和对照组43例,治疗组服用普济宣肺消毒饮,对照组用急支糖浆治疗,观察对咯痰的影响,疗程为7d.结果 治疗组对咯痰、发热、头痛、恶风等症状有明显治疗作用,治疗后咯痰疗效和评分低于对照组,化痰疗效优于对照组(P<0.05).结论 普济宣肺消毒饮有一定的化痰作用.  相似文献   
992.
晚孕期胎盘因子对小鼠淋巴细胞增殖的影响   总被引:1,自引:0,他引:1  
通过晚孕期胎盘因子(PF)对小鼠淋巴细胞体外增殖的作用,探讨PF对正常机体免疫系统和免疫功能的效应。分离小鼠淋巴细胞,用ConA刺激其增殖,并分别与晚孕期不同浓度的PF作用,于48 h和72 h用活体染料羧基荧光素乙酰乙琥珀酰亚胺酯(CFSE)标记,流式细胞术检测增殖。于48 h碘化丙啶染色,流式细胞术检测细胞周期分布。结果显示,晚孕期PF在48 h和72 h时间点均能显著促进ConA诱导的小鼠淋巴细胞增殖反应,且效应与剂量呈正相关。晚孕期各浓度PF组G0期所占比率均显著低于对照组,且浓度越大,比率越低,组间两两比较有统计学意义。各浓度PF组S期所占比率均显著高于对照组,各浓度PF组G2/M期所占比率均显著高于对照组,25%PF组G2/M期所占比率均显著高于5%PF组和15%PF组。晚孕期PF通过促进小鼠淋巴细胞由G1期向S和G2/M期而促进ConA刺激小鼠淋巴细胞的增殖反应,提示PF具有免疫调节的功能,可以提高机体的免疫功能。  相似文献   
993.
通过对HPV L1序列进行比对,发现HPV L1 C-末端存在长30个氨基酸残基的保守序列短肽;出于检测短肽是否可以诱生HPV多种型别交叉抗体的目的,将该序列短肽加弗氏佐剂用于日本大耳白兔和BALB/c小鼠免疫,然后用ELISA方法检测此免疫动物血清及其分泌物中的IgG抗体滴度,发现此免疫动物体内已诱生出高滴度的血清IgG抗体(>1∶20000);再用ELISA、免疫组织化学和Western blot的方法对此诱生血清抗体与HPV阳性宫颈癌细胞株的反应情况进行检测,发现这些短肽抗血清可与16、18型HPV L1很好地进行反应,其对照组呈现阴性。这一研究结果表明短肽可以诱生HPV多种型别交叉抗体。它对后续研发HPV L1广谱疫苗或检测试剂盒具有重要意义。  相似文献   
994.
目的 探讨乳腺癌保乳手术中,采用梭柱型或圆柱型区段切除对保乳切缘肿瘤残留的影响,比较两种方法的优缺点,以期寻找一种兼顾两种方法优点的手术方式.方法 对于行乳腺癌保乳术的入组患者分别采用梭柱型保乳区段切除术(A组)或圆柱型保乳区段切除术(B组),比较两种术式手术标本切缘的肿瘤残留情况;随访比较两组患者术后1年内局部复发及...  相似文献   
995.
Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry and the construction of this motif with high atom economy is the focus of the current research. Specifically, N-methyl amides are valuable building blocks in natural products and pharmaceutical science. Due to the volatile nature of methyl amine, the generation of N-methyl amides using simple acids with high atom economy is rare. Herein, we disclose an atom economic protocol to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis. This protocol is operationally simple and compatible with a range of aliphatic and (hetero)aromatic acids with very good yields (60–99%). Moreover, the Fe3O4 can be easily recovered and high efficiency is maintained for up to ten cycles.

The generation of N-methyl amides using simple acids with high atom economy is rare owning to the volatile nature of methyl amine. Herein, an atom economic protocol was disclosed to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis.

Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry.1 It is widely distributed in natural products, synthetic drugs and functional polymers, and is also the key chemical connection in proteins.2 It has been shown that amide bond formation alone accounts for 65% of all preliminary screening reactions in the pharmaceutical industry.3 This means the generation of amide bonds with high atom efficiency is of high practical importance. And not surprisingly, ‘amide formation avoiding poor atom economy reagents’ was voted as the top challenge for organic chemistry by the ACS Green Chemistry Institute in 2007.3From synthetic point of view, the ideal way to produce amide bonds would be the direct coupling of readily available carboxylic acids and amines, but this process is thermodynamically unfavourable due to the formation of the corresponding carboxylate-ammonium salt,4 therefore, stoichiometric amount of coupling reagents, such as DCC, DIC, EDCI, HATU, HBTU, HCTU, SOCl2, BOP, acid chloride etc, are generally required to sidestep thermal conditions for amide bond formation.5 These reagents are highly successful, but the process generally suffers from poor atom economy and side products removal issue especially in the large-scale applications.5 To overcome these drawbacks, “nonclassical” amide bonds formation routes were investigated.6 In these processes, the catalyst takes the role of a coupling reagent in generating an active ester suitable for amidation in a waste-free manner. However, these processes have not been applied in the preparation of N-methyl amides, probably because the methyl amine was delivered in its hydrochloride salt, alcoholic or aqueous form due to its volatile nature.On a different note, N-methyl amides are extensively presented in numerous natural products and pharmaceutical molecules, as shown in Fig. 1,7 and the methylation of amides is a promising way to improve the pharmacological property of molecules.8 However, the synthesis of N-methyl amides compounds relies heavily on non-catalytic approaches.5,9 Catalytic approaches were also investigated by Hisaeda,10 Kundu,11 Li,12 Guo,13 Yu,14 Maruoka,15 Wang,16 Chen,17 Lamaty18 and their co-workers starting from nitriles, primiary amides, aldoximes, aldehydes, lignin, carbamoylsilane and alcohols. Until recently, Thakur,19 Marce,20 Sadeghzadeh21 and their co-workers developed elegant N-methyl amidation approach starting from carboxylic acids under nano-MgO, diatomite Earth@IL/ZrCl4 and Mg(NO3)2·6H2O catalysis respectively, while limitations like poor substrate scope or sophisticated tailored catalyst still persist. Mindful of all the above issues, developing an N-methyl amidation process of simple carboxylic acids, which is still of great challenge in synthesis, and establishing a broad (hetero)aryl scope with high atom economy from commercial available reagents and catalysts were critical considerations in this study. Moreover, the significance of N-methyl amides combined with our interests in the development of green synthetic approaches motivated us to explore the direct coupling of the carboxylic acids and isothiocyanates. To the best of our knowledge, this is the first successful work using isothiocyanatomethane to prepare N-methyl amides.Open in a separate windowFig. 1Marketed drugs bearing N-methyl amide group.Our initial investigation begins with phenylacetic acid and isothiocyanatomethane as model substrate for condition optimization. Using acetonitrile as solvent, only trace amount of product was detected under catalyst free or p-toluenesulfonic acid (PTSA) catalysis conditions (
EntryAdditiveTime (h)CatalystYield (%)
1245
224PTSA
348TEA17
448DBU45
548DMAP43
648DBN51
748DABCO65
8LiBr48DABCO71
9Mn(OAc)248DABCO75
10MnO48DABCO79
11MgO48DABCO88
12Al2O348DABCO85
13Fe3O448DABCO98
14Fe3O424DABCO75
15bFe3O448DABCO80
Open in a separate windowaReactions were run on 1 mmol 1a and 1.1 mmol 2a with 10 mol% catalyst and 10 mol% additive in 1 mL of MeCN at 85 °C for 48 hours unless otherwise noted.bReaction was conducted at 60 °C.Firstly, different acids were employed to react with isothiocyanatomethane and the results were summarized in Open in a separate windowaReactions were run on 1 mmol 1 and 1.1 mmol 2 with 10 mol% DABCO and 10 mol% Fe3O4 in 1 mL of MeCN for 48 hours at 85 °C unless otherwise noted.Subsequently, aromatic and heteroaromatic acids were tested for their compatibility with current reaction conditions and the results were summarized in Fig. 1) respectively, and all could be convenient prepared using current procedure with excellent yields.Substrate scope for the amidation reactiona
Open in a separate windowaReactions were run on 1 mmol 1 and 1.1 mmol 2 with 10 mol% DABCO and 10 mol% Fe3O4 in 1 mL of MeCN for 48 hours at 85 °C unless otherwise noted.Furthermore, to demonstrate the synthetic utilization of our methodology, the preparation of bioactive compounds was demonstrated Scheme 1. Compounds 3as is a patent HDAC4 inhibitor.22 Under the standard reaction conditions, 3as could be obtained from commercial available 1as in 92% yield. Our procedure is much more atom economy as it excluded the usage of activating reagent and excess amount of base. In a recent report, Yang group reported their pilot-scale synthesis of substituted phenylacetamides to tetrahydroisoquinoline-2-ones.23 In their practice, corrosive thionyl chloride was applied as activating reagent and large excess amount of methyl amine was required, however, moderate yield of 3a was obtained, while our method can achieve better yield along with the exclusion of corrosive thionyl chloride. Following this report, tetrahydroisoquinoline-2-one 4a could be obtained in 82% yield, which could be used in the preparation of various bioactive 4-aryl-tetrahydroisoquinolines 5a with known procedure.24Open in a separate windowScheme 1Application of N-methyl amide.Finally, owing to the magnetic nature of Fe3O4, we try to recover the Fe3O4 from the reaction system and test its efficiency. As the Fe3O4 is always stick to the magnetic stir bar, after the termination of the reaction, the reaction solution was pour out and the tub along with the magnetic stir bar was rinsed with MeCN three times, oven dried and used for the next cycle. The results shown that the Fe3O4 could be used 10 times and still maintained very good efficiency (Fig. 2).Open in a separate windowFig. 2The efficiency of recovered Fe3O4.Combined with the literature reports and experimantal observation,25 a plausable mechanism was proposed in Scheme 2. Firstly, the carboxylic acid reacts with the Fe3O4 to get iron (II and III) carboxylate A, which will coordinate to the intermediate B generated from DABCO and isothiocyanate to get intermediate C. Then, one of the carboxylate attack intermediate B to release DABCO and generates intermediate D. Intermediate D go through an intramolecular addition to generate intermediate E, which go through a rearrangement reaction to get intermediate F with the release of carbonyl sulfide. Finally, the protonation of F with carboxylic acid to get the final product and regenerate the iron (II and III) carboxylate A.Open in a separate windowScheme 2Proposed reaction mechanism.  相似文献   
996.
新型循环动力模式大鼠心脏移植模型的建立     
赵曙光  范慧敏  周谦君  孔祥  汪进益  刘中民 《同济大学学报(医学版)》2007,28(6):49-51
目的目前,国内所有大鼠腹部异位心脏移植均沿袭了Corry的传统的移植心脏血流循环构建模式,但其操作难度限制了其广泛应用,尝试一种新型的、更简介高效的心脏移植循环重建新技术。方法本方法利用大鼠供体大鼠肝脏以上下腔静脉代替肺动脉与受体肾以下腔静脉吻合。结果新方法双血管缝合时间为(30.5±2.1)min,明显短于传统血管吻合方法(39.7±3.6)min,术后心脏复跳时间也由原来的(1.9±0.4)min缩短到(1.1±0.2)min。结论新循环重建技术降低了大鼠心脏移植难度,缩短了移植心脏缺血和复跳时间。  相似文献   
997.
Ⅲ型胶原α链基因mRNA的表达与舌苔形成的关系研究     
张春兵  范媛  詹瑧  张军峰  汪红 《检验医学》2007,22(5):524-527
目的研究Ⅲ型胶原α链基因表达水平与舌苔形成之间的关系。方法应用基因芯片技术和实时荧光定量逆转录-聚合酶链反应(RT-PCR)技术,检测Ⅲ型胶原α链在不同舌苔中的表达水平。结果基因芯片显示,常见舌苔中Ⅲ型胶原α链表达水平差异有统计学意义;实时荧光定量PCR证实从高到低依次为:黄厚苔〉白薄苔〉白厚苔〉无苔〉黄薄苔〉胎儿白薄苔。结论常见舌苔中,Ⅲ型胶原α链表达水平有差异,提示Ⅲ型胶原α链基因表达水平的调控在舌苔形成过程中可能有一定的意义。  相似文献   
998.
气传花粉播报平台在过敏性鼻炎预防治疗中的应用研究          下载免费PDF全文
刘晓佳  黄海云  梁红宇  邓卓怡  王宏宇  王冲  李椿莹  刘晓玲 《中国耳鼻咽喉头颈外科》2022,29(1):41-44
目的 利用气传花粉播报平台进行花粉浓度播报及AR防治措施普及,结合相关数据分析,为患者对疾病的防治提供指导。方法 于2019及2020年的3~10月进行花粉采集及阅片计数,通过播报平台进行花粉浓度日播报,统计同期AR患者门诊就诊情况及平台用户流量,分析以上数据寻找本地区花粉分布规律与AR患者就诊相关性,为今后指导患者预防治疗打好前期工作基础。结果 呼和浩特地区花粉浓度存在春季和夏秋季两个高峰期,浓度变化趋势与门诊AR就诊人次及平台用户流量呈正相关。结论 借助本地区建立的气传花粉播报平台,在发布实时花粉浓度预警的同时可以指导AR患者及时采取预防性治疗,对减轻症状,降低严重并发症起到较好辅助作用。  相似文献   
999.
万古霉素血药浓度与临床疗效及急性肾损伤的关系     
李燕  王学彬  陈礼治  杨云云  沈林娟  王卓 《第二军医大学学报》2021,42(3):281-286
目的 探讨万古霉素稳态谷浓度(Cmin)和峰浓度(Cpeak)与临床疗效及急性肾损伤(AKI)的关系.方法 回顾性纳入2015年11月至2019年4月于海军军医大学(第二军医大学)长海医院住院、住院期间使用万古霉素且至少测定了1次万古霉素Cmin或Cpeak的136例患者作为研究对象,收集患者的基本信息及相关指标.万古...  相似文献   
1000.
1例脓毒症相关性脑病的临床治疗     
朱文洁  王晓平 《世界临床药物》2022,43(2):179-182
脓毒症相关性脑病是在严重感染脓毒症基础上,排除中枢神经系统感染、脑血管意外等中枢神经系统疾病及器质性疾病和代谢性疾病引起的意识障碍性疾病。该文作者在临床工作中遇到 1 例,予以积极抗感染、连续性肾脏替代疗法、降颅压,以及气管插管呼吸机辅助通气、补液支持对症(护肝、抗癫痫等)治疗后好转出院。该病例警示临床医生,遇到严重感染脓毒症的患者出现的意识障碍,要考虑到脓毒症相关性脑病的可能,为临床上类似患者的治疗提供一些借鉴经验。  相似文献   
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