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71.
固体光气法合成洛莫司汀 总被引:4,自引:0,他引:4
以固体光气(三光气)为起始原料,经过在无水甲苯溶液中与环己胺反应生成环己基异氰酸酯,再经与氨基乙醇和氯化亚砜的一锅法反应生成1-(2-氯乙基)—3—环己基脲(氯化物),最后再亚硝化,即得洛莫司汀。原料易得,各步反应条件温和,操作方便,步骤比文献方法(4步)减少一步,总收率由文献方法的23.7%提高为49.8%,适于工业规模制备。 相似文献
72.
茎突CT薄层冠状扫描在诊断茎突过长综合征中的价值 总被引:1,自引:2,他引:1
目的 探讨“一点一线垂直法”茎突CT薄层冠状扫描在诊断茎突过长中的价值。方法测量72例双侧茎突的长度、方位、形态、厚度、尖端与咽侧壁距离,总结茎突过长病人的临床症状与诊断。 结果 ①41例67侧长度超过3.0cm,符合茎突过长的诊断;②12例12侧茎突虽未超过3.0cm(均在2.5~2.9cm),且茎突方位角>20°、末端与咽侧壁的距离<20mm,并有临床症状的应考虑茎突过长综合征;③按茎突的形态进行分型:锥型(分直锥、弧锥),束状型,分节型,发育不良型。其中分节型与临床症状有密切关系。结论 ①茎突CT薄层冠状扫描能清晰显示茎突的长度、形态、厚度、末端与咽侧壁距离,是诊断茎突过长的一种可靠方法;②“一点一线垂直法”茎突CT薄层冠状扫描无需进行图像重建,可操作性强、简捷易行、便于推广。 相似文献
73.
目的:探索金银花中总黄酮最佳提取工艺。方法:采用正交法考察乙醇浸泡浓度,萃取时间、乙醇洗脱浓度,物料比 4 个因素对金银花中总黄酮得率的影响。结果:金银花中总黄酮的最佳提取工艺;用 30 倍于样品重的 80%的乙醇浸泡 24h 后继用超声法提取 40min,以 60%的乙醇洗脱。结论 以超声波法提取的总黄酮含量高,操作简便,节省燃料和时间,提取较完全,此法宜工业化生产。 相似文献
74.
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76.
OBJECTIVE: To test a quality improvement approach called COPE (Client-Oriented, Provider-Efficient services), for use in strengthening health systems and supporting Integrated Management of Child Health (IMCI) efforts. DESIGN: Pre- and post-intervention observations of client/provider interactions, facility audits, staff and client surveys, and focus groups to evaluate differences between eight COPE intervention and eight matched non-intervention facilities after a 15-month intervention in 2001. SETTING: Primary care clinics in Guinea and Kenya. STUDY PARTICIPANTS: Health care providers and child caregivers. INTERVENTIONS: Over 15 months, the intervention supported four COPE exercises at each intervention site, supported supervisor training in quality management, and organized minimal training in topics selected by site staff as areas where training was needed. MAIN OUTCOME MEASURES: Differences in staff's and child caregiver's knowledge, attitudes, and practices; differences in the quality of services provided. RESULTS: On almost every quality indicator (over 65 indicators), whether reported by staff, observed by evaluators, or reported by clients, the intervention sites performed statistically significantly better than control sites. INTERVENTION: sites were cleaner and more pleasant, with more respect and information for clients, and more privacy. Staff had better personal communication skills, better diagnostic skills, and prescribing practices and gave better home care instructions to carers. Clients in intervention sites were more informed and more satisfied, and their children had better immunization coverage than those in control sites. CONCLUSION: COPE is a simple process, yet our study confirms that it can have a very dramatic effect on the quality of services. This study demonstrated how all areas of quality can be addressed by empowering health care providers to take action by using COPE. We suggest that COPE can complement Integrated Management of Childhood Illness (IMCI) training and can help to achieve better health for children. 相似文献
77.
OBJECTIVES: Little is known about the quality of primary care in Saudi Arabia, despite the central role of primary care centers in Saudi health strategy. This study presents an overview of quality of primary care in Saudi Arabia, and identifies factors impeding the achievement of quality, with the aim of determining how the quality of Saudi primary care could be improved. METHOD: Using a systematic search strategy, data were extracted from the published literature on quality of care in Saudi primary care services, and on barriers to achieving high-quality care. RESULTS: Of the 128 studies initially identified, 31 met the inclusion criteria for the review. Studies identified were diverse in methodology and focus. Components of quality were reviewed in terms of access and effectiveness of both clinical and interpersonal care. Good access and effective care were reported for certain services including: immunization, maternal health care, and control of epidemic diseases. Poor access and effectiveness were reported for chronic disease management programs, prescribing patterns, health education, referral patterns, and some aspects of interpersonal care including those caused by language barriers. Several factors were identified as determining whether high-quality care was delivered. These included management and organizational factors, implementation of evidence-based practice, professional development, use of referrals to secondary care, and organizational culture. CONCLUSION: There is substantial variation in the quality of Saudi primary care services. In order to improve quality, there is a need to improve the management and organization of primary care services. Professional development strategies are also needed to improve the knowledge and skills of staff. 相似文献
78.
目的:分析麻黄蜜炙后生物碱与挥发油两类主要成分的变化.方法:用气质联用方法分析蜜炙后挥发性成分的变化,按<中国药典>测麻黄总碱的方法比较蜜炙后麻黄总碱的变化情况.结果:蜜炙后挥发性成分变化较大,其中异桉叶素、对-聚伞花素、D-柠檬烯、桉叶素、T-萜品烯等含量显著升高,苯甲醛、四甲基吡嗪、对乙烯基茴香醚、1-α-松油醇、T-松油醇等含量均降低;总生物碱含量则均表现为减少.结论:麻黄蜜炙后辛散发汗力减弱,润肺平喘作用增强,可能与总碱含量减少及挥发油特征变化有关,这为研究古人的炮制机理提供新的实验依据. 相似文献
79.
目的:探讨、研究急性肛周脓肿一期根治新术式.方法:回顾分析 1996~ 2004年 123例急性肛周脓肿一期根治术式 改进后病人的临床资料.结果:所有病人均一次性治愈,无术后复发肛瘘及遗留肛门失禁.结论:采用该术式治疗急 性肛周脓肿,具有治愈率高、病人痛苦小、手术恢复快、费用低、并发症少等优点. 相似文献
80.
枕下经颈-颈静脉突入路达颈静脉孔区的显微解剖研究 总被引:1,自引:1,他引:1
目的 研究一期切除颈静脉孔区复杂性肿瘤的微创手术人路。方法 选择经10%福尔马林固定成人头颈标本10具,显微镜下模拟枕下经颈一颈静脉突人路的手术操作,逐层显露颈静脉孔区,研究该区显微解剖特征及显露范围。结果 该人路直接沿乙状窦、颈内静脉的移行方向显露颈静脉孔区结构,其中后颅窝可经枕下显露,颞下窝藉寰椎与下颌升支间的自然间隙显露。通过切除颈静脉突和迷路下骨质分别自后、外、下和上方显露颈静脉孔。头侧直肌是界定颞下窝结构和枕下三角内结构的确切标志。后组颅神经,交感千和颈内动、静脉行于其前方,椎动脉寰椎上段及其周围的静脉丛行于其后方。结论 枕下经颈一颈静脉突人路可自多个方向充分显露颈静脉孔区结构,且可保护面神经、迷路、耳蜗和椎动脉等结构免受不必要的损伤。 相似文献