CATALYTIC HYDROGENOLYSIS IN LIQUID AMMONIA.* CLEAVAGE OF Nα-BENZYLOXYCARBONYL GROUPS FROM CYSTEINE-CONTAINING PEPTIDES WITH tert-BUTYL SIDE CHAIN PROTECTION

To exemplify the extension to synthesis of sulfur-containing peptides of the _Nα-benzyloxycarbonyl and side chain tert-butyl protective group combination, somatostatin has been synthesized via incremental chain elongation starting from the COOH-terminal cysteine. Cleavage of the _Nα-benzyloxycarbonyl groups was achieved in high yield, at each stage, by palladium-catalyzed hydrogenation in liquid ammonia. All side chain functionalities including the cysteine thiol groups were blocked by tert-butyl-derived groups. Each gave rise to individual n.m.r. signals which permitted sensitive characterization of all intermediate protected peptides. Mild conditions were used for the removal of all protecting groups from the completed somatostatin tetradecapeptide. The tert-butyl thiol protective groups were readily and completely cleaved by mercuric acetate at pH 4. Oxidation of dihydrosomatostatin with potassium ferricyanide provided somatostatin in good yield. The results indicate that the absolute selectivity between α-amine and side chain protective group cleavage afforded by _Nα-benzyloxycarbonyl hydrogenolysis in the presence of -tert-butyl groups may now be extended to synthesis of cysteine- and methionine-containing peptides.     

老年心肌缺血预适应延迟保护作用钝化机制的研究进展

缺血预适应是心肌抗缺血性损伤的最有效的内源性保护机制,但是老年人缺血预适应的延迟保护作用却明显削弱甚至消失,原因和产生心肌缺血预适应延迟保护作用环节的功能下降有关,其中线粒体功能的退化和障碍最为重要。     

从六经辨证之三阴病干预IGR大鼠的实验研究

目的观察从六经辨证三阴病入手,采用扶阳护阴,运转枢机法对IGR大鼠糖脂代谢、脂毒性、胰岛素抵抗的影响,探讨该法对糖尿病前期的干预疗效及机制。方法 32只SD大鼠分为正常组、模型组、中药组、二甲双胍组。观察各组大鼠4周后血糖、血脂、游离脂肪酸、胰岛素变化。结果六经辨证三阴病入手干预IGR大鼠可降低血糖和胰岛素抵抗指数,升高胰岛素敏感指数（P〈0.05）,降低游离脂肪酸优于二甲双胍组（P〈0.05）。结论六经辨证三阴病入手,采用扶阳护阴,运转枢机法具有纠正糖脂代谢紊乱,降低脂毒性,减轻胰岛素抵抗的作用。     

护肝片在防治抗结核药物所致肝损伤的临床应用

目的探讨护肝片在防治抗结核药物所致肝损伤中的应用前景及疗效。方法对比分析治疗组与对照组之间在抗结核治疗中肝损害发生率、损害程度、发生时间,并进行差异显著性分析。结果 535例病例中,肝损害发生率为6.92%,治疗组ALT升高9例,发生率为3.37%,升高幅度在50~120U之间,损害多发生在治疗的2~4周,之后逐渐减少,HBsAg阳性病人发生率高,损害程度轻。对照组发生ALT升高28例,发生率为10.48%,升幅在75~180U之间,损害多发生于开始治疗4周左右,HBsAg阳性病人肝损害多为中重度损害,两组肝损害比较差异有统计学意义（χ2=9.34,P〈0.01）。结论潜在的肝损害人群中,以HBsAg阳性人群和老年人群最为危险,在抗结核治疗中应全程加服护肝片,并密切注意肝功能的变化。     

Advocacy in nursing – perceptions of practising nurses

• ? This paper reports on a qualitative study which examined the interpretation of patient advocacy by practising nurses.
• ? Focus group interviews, which allowed respondents to recount and share their particular ‘stories’ of patient advocacy, were used to collect data.
• ? Results indicate that a triadic model of advocacy predominated which involved the nurse in a conflict/potential conflict situation. The patient's requests, the patient's fear, the patient's vulnerability or threats to the patient's human rights provoked an advocacy response in the perceptive nurse. The nurse was sustained in the role through patient recognition, the nurse–patient relationship, emotional strength, moral justification and knowledge/expertise legitimacy.
• ? The nurse used direct and indirect means to protect the patient against incompetent/inappropriate practice and/or represent patient/family choice, the advocacy activity resulting in positive or negative outcomes.
• ? In conclusion it is argued that if the triadic conflict model of advocacy outlined by this research is to be sustained by practising nurses, the potential risks involved should be recognized. Professionalization of the role may be the only way forward if the ethical code (United Kingdom Central Council, 1992) continues to make patient advocacy a mandatory activity for the professional nurse.

     

符为民教授治疗特发性痉挛性斜颈证治经验

目的:探讨符为民教授对特发性痉挛性斜颈的诊治思路和临证经验。方法:通过跟随符为民教授临证抄方,收集相关医案总结符为民教授运用中医疗法治疗特发性痉挛性斜颈临床诊疗思路及用药规律并以典型医案加以分析。结果:符为民结合现代人生活习惯,认为现代人特发性痉挛性斜颈以肝肾阴虚为致病之本,风寒湿伤阳为发病之标。病机为风寒湿侵袭,阳气受损筋失温煦;肝肾亏虚朋液失充血不养筋;水不涵木,虚风内动,经络受扰。病理性质虚实夹杂。本病非急症,采取"标本同治"原则。符教授从肺入手,以治肺调阳为主要治疗原则。以实肺气,温肺阳为主要治法,使筋得温煦而柔和。治疗全程均辅以滋补肝肾以养血,使筋得濡养而有力。后期调护更以滋补肝肾之阴,搜风剔络善后。此外,符教授还注重病后调养。充分体现中医"治未病"基本思想。其临床疗效斐然,所举案例效果确切。结论:符为民教授论治特发性痉挛性斜颈的临床经验值得学习和推广。     

不同诱导方式制备的大鼠肝匀浆代谢酶活性及冻储方式的比较

目的：研究7种不同诱导方式制备的大鼠肝匀浆的代谢酶活性,并探讨用低温液体法保存肝匀浆的可行性。方法：SD雄性大鼠,每组6只,分别用苯巴比妥（PB）、β-萘黄酮（βNF）和多氯联苯（PCB）3种诱导剂,在不同给药途径、不同剂量、不同时间、单一诱导或联合诱导等7种不同诱导方式下,制备肝匀浆,并在0、-20和-40℃贮存。选择2-氨基芴（2AF）、吖啶橙（AO）和环磷酰胺（CP）3种间接致突变剂在Ames试验中应用TA100、TA98或TA97,对上述诱导方式和贮存方式、贮存时间下获得的肝匀浆进行肝代谢酶活性的考察。结果：各组肝匀浆对间接致突变剂2AF、AO和CP均呈代谢活酶性阳性;加诱导剂的肝匀浆代谢酶活性比不加诱导剂的更强;联合诱导组的肝匀浆代谢酶活性比单独诱导组的更高;不同给药途径,不同诱导时间、不同诱导剂量、联合诱导与多氯联苯（PCB）诱导等,其肝匀浆代谢酶活性基本一致。加入冰冻保护剂的肝匀浆低温贮存液在4℃可贮存4周;在-20和-40℃下贮存24周代谢酶活性未明显降低。结论：PCB诱导组肝匀浆代谢酶活性与联合诱导组基本一致,均大于单独诱导组,且后者大于未诱导组;给药途径、诱导时间和剂量对肝匀浆代谢酶活性影响不大;肝匀浆低温贮存液保存于-20和-40℃环境下24周内能够保证代谢酶的活性。     

奥丽汀健齿露对定菌鼠龋齿发生的影响

目的:探讨奥丽汀健齿露对龋齿的预防作用,建立防龋食品功能性评价方法。方法:采用变形链球菌(S.matans8148)、茸毛链球菌(S.Sobrinus6715)以及上述两种菌混合物定菌SPF级W istar大鼠,给予致龋饲料建立三种龋损模型,观察各组大鼠磨牙患龋情况,参照Keyes经典计分标准进行龋齿计分。并采用所建立的三种龋损模型观察奥丽汀健齿露对大鼠龋损的影响。结果:三种定菌方式致龋性不同:动物感染茸毛链球菌者比感染变形链球菌者龋齿计分低,差异有显著性(P<0.01),混合定菌大鼠龋齿计分比变形链球菌低,而比茸毛链球菌者高,差异有显著性(P<0.01,P<0.05)。与相应的对照组比较,实验组定菌大鼠的Dx、Dm、D s值显著降低(P<0.01)。结论:奥丽汀健齿露能够有效地抑制龋病的发生和发展。     

麝香保心pH依赖型梯度释药微丸的体外释放度研究

目的 考察麝香保心pH依赖型梯度释药微丸的体外释放度。方法 分别以HPMC,EudragitL-30D-55,EudragitL100/S100为包衣材料制备pH依赖型梯度释药微丸,以冰片和人参总皂苷为检测指标。按照《中国药典》2000年版溶出度测定法。在模拟人体胃肠道pH变化条件下进行释放度实验。结果 冰片和人参总皂苷释放度的f2值为79.6。结论 脂溶性成分冰片和水溶性成分人参冲刷 皂苷在缓释的同时基本上达到了同步释放。     

麝香保心分散片的制备和人参总皂苷的体外溶出度研究

目的　制备麝香保心分散片 ,考察人参总皂苷的体外溶出度。方法　以PVPP为崩解剂、MCC为填充剂、CMC Ca为溶胀性辅料、1%HPMC水溶液为粘合剂 ,制备麝香保心分散片 ;采用比色法以人参总皂苷为测定指标 ,考察其体外溶出度。结果与结论　按最佳工艺制备的麝香保心分散片在 (2 0± 1)℃水中于 15s内可完全崩解且分散均匀 ,其指标性成分人参总皂苷的溶出速率明显高于麝香保心丸