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31.
从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,~1HNMR,~(13)CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。  相似文献   
32.
报道了用GC/MS方法及衍生化技术研究6甲氧基正丁苯酞(MBP)在大鼠肝微粒体中的代谢转化结果。6甲氧基正丁苯酞在苯巴比妥(PB)诱导的大鼠肝微粒体中主要转化为3羟基、γ羟基取代物,6羟基正丁苯酞与一个环氧化代谢产物  相似文献   
33.
Study ObjectivesExamine how different trajectories of reported sleep duration associate with early childhood cognition.MethodsCaregiver-reported sleep duration data (n = 330) were collected using the Brief Infant Sleep Questionnaire at 3, 6, 9, 12, 18, and 24 months and Children’s Sleep Habits Questionnaire at 54 months. Multiple group-based day-, night-, and/or total sleep trajectories were derived—each differing in duration and variability. Bayley Scales of Infant and Toddler Development-III (Bayley-III) and the Kaufman Brief Intelligence Test- 2 (KBIT-2) were used to assess cognition at 24 and 54 months, respectively.ResultsCompared to short variable night sleep trajectory, long consistent night sleep trajectory was associated with higher scores on Bayley-III (cognition and language), while moderate/long consistent night sleep trajectories were associated with higher KBIT-2 (verbal and composite) scores. Children with a long consistent total sleep trajectory had higher Bayley-III (cognition and expressive language) and KBIT-2 (verbal and composite) scores compared to children with a short variable total sleep trajectory. Moderate consistent total sleep trajectory was associated with higher Bayley-III language and KBIT-2 verbal scores relative to the short variable total trajectory. Children with a long variable day sleep had lower Bayley-III (cognition and fine motor) and KBIT-2 (verbal and composite) scores compared to children with a short consistent day sleep trajectory.ConclusionsLonger and more consistent night- and total sleep trajectories, and a short day sleep trajectory in early childhood were associated with better cognition at 2 and 4.5 years.  相似文献   
34.
目的:采用不同方法对白血病HL60细胞株进行冻存和复苏,观察生物学特性改变,筛选最佳冻存复苏方案。方法:实验于2006-04/06在吉林医药学院临床检验实验室(国家三级标准)进行。①HL60细胞株由中国科学院上海生物细胞研究所提供。将欲冷冻保存的HL60细胞调整到良好的生长状态(对数生长期),随机数字表法分成4组,离心收集后在含体积分数为0.1小牛血清的RPMI-1640培养基中分别加入二甲基亚砜,使其终浓度依次为50,100,150,200g/L。冻存15d后,每组取1支冻存管复苏并接种于细胞培养板,培养12h后用锥虫蓝拒染法计算细胞复苏率。②选择冻存条件和冻存细胞密度相同的两支冻存管,按不同方法进行HL60细胞复苏。37℃水浴传统复苏法:立即将冻存管置于37℃水浴中,待融化后800r/min离心5min,吸去上清液,加入含体积分数为0.1小牛血清的RPMI-1640培养基,混匀后接种于细胞培养板,1mL/孔,9孔/组,置于体积分数为0.05的CO2培养箱37℃继续培养。40℃溶解后再37℃恒温改良复苏法:将冻存细胞于40℃水浴中迅速溶解,转入37℃水浴箱,融化后离心、加培养基等操作同传统复苏法。复苏细胞培养12h后采用锥虫蓝染色计算细胞存活率。③用无血清RPMI-1640培养基制备HL60细胞悬液,按3×107L-1密度接种于细胞培养板中,1mL/孔,然后分别加入体积分数为0.05,0.1,0.12,0.15,0.2的灭活小牛血清,每种血清浓度设置8个试验孔,并分别于培养12,24,36,48,60,72,84,96h后计数每孔细胞数量,并绘制细胞生长曲线。结果:①不同浓度二甲基亚砜冻存后HL60细胞复苏率的比较:二甲基亚砜200g/L组的细胞复苏率明显低于二甲基亚砜50,100,150g/L组[(64.6±2.8)%,(87.0±1.4)%,(86.4±2.1)%,(85.7±2.8)%;t=25.44,P<0.01],二甲基亚砜50,100,150g/L组间差异无显著性意义(t=0.82~1.44,P>0.05)。②不同复苏方法HL60细胞存活率的比较:与37℃水浴传统复苏法比较,40℃溶解后再37℃恒温改良复苏法的细胞存活率显著升高[(69.5±1.5)%,(87.4±1.8)%,t=23.24,P<0.01]。③RPMI-1640培养基不同血清含量对HL60细胞生长情况的影响:在体积分数为0.05的血清含量培养基中,HL60细胞基本不生长,且有逐渐死亡的趋势;在体积分数为0.1的血清含量培养基中,HL60细胞生长趋势明显,但生长速度相对较慢;在体积分数为0.12,0.15,0.2的血清含量培养基中,HL60细胞生长迅速,3种血清浓度间细胞生长趋势无明显差异。结论:以50g/L二甲基亚砜作为HL60细胞冻存保护剂、联合40℃溶解后再37℃恒温改良复苏法可使细胞保持最佳生物学特性,体积分数为0.12的血清含量为HL60细胞常规培养的最适浓度。  相似文献   
35.
Although diphenhydramine has been shown to produce longer duration of spinal block than lidocaine, few studies disclose its skin infiltrative anesthesia when compared with a long‐lasting local anesthetic, bupivacaine. The purpose of this study was to investigate whether diphenhydramine elicited cutaneous analgesia in comparison with bupivacaine. After inhibition of cutaneous trunci muscle reflex via subcutaneous injection of drugs in rats, we examined the local anesthetic effect of diphenhydramine and bupivacaine as infiltrative cutaneous analgesia in a dose‐dependent fashion. We showed that diphenhydramine, as well as bupivacaine displayed a dose‐dependent cutaneous analgesia in response to dorsal cutaneous noxious stimuli. The relative potency (50% effective dose) was bupivacaine (0.023 [0.013–0.035]%) > diphenhydramine (0.078 [0.068–0.091]%; < 0.001). On an equipotent basis, diphenhydramine had a similar duration of action to bupivacaine. Neither local injection of saline nor intraperitoneal administration of a large dose of diphenhydramine or bupivacaine produced cutaneous analgesia (data not shown). We conclude that diphenhydramine is less potent than bupivacaine at producing cutaneous analgesia. At equipotent doses for infiltrative cutaneous analgesia, the duration of action of diphenhydramine is equal to that of bupivacaine.  相似文献   
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38.
Background: Spontaneous bacterial empyema (SBE) is a complication of cirrhotic patients in which a pre‐existing pleural effusion becomes infected. This retrospective study was designed to investigate the bacteriology and outcome predictors of SBE in cirrhotic patients. Methods: Medical records of cirrhotic patients treated in a tertiary care university hospital from December 2004 to December 2008 were retrospectively reviewed. Results: Of 3390 cirrhotic patients seen during the study period, 81 cases of SBE were diagnosed. The incidence of SBE was 2.4% (81/3390) in cirrhotic patients and 16% (81/508) in patients with cirrhosis with hydrothorax. There were 46 monomicrobial infections found in 46 SBE patients. Aerobic Gram‐negative organisms were the predominant pathogens (n=29, 63%), and Escherichia coli (n=9, 20%) was the most frequently isolated sole pathogen. The mortality rate of SBE was 38% (31/81). Univariate analysis showed that Child–Pugh score, model for end‐stage liver disease (MELD)–Na score, concomitant bacteraemia, concomitant spontaneous bacterial peritonitis, initial intensive care unit (ICU) admission and initial antibiotic treatment failure were predictors of poor outcomes. Multivariate regression analysis demonstrated that the independent factors related to a poor outcome were initial ICU admission [odds ratio (OR): 4.318; 95% confidence interval 1CI) 1.09–17.03; P=0.037], MELD–Na score (OR: 1.267; 95% CI 1.08–1.49; P=0.004) and initial antibiotic treatment failure (OR: 13.10; 95% CI 2.60–66.03). Conclusion: Spontaneous bacterial empyema in cirrhotic patients is a high mortality complication. The independent factors related to poor outcome are high MELD–Na score, initial ICU admission and initial antibiotic treatment failure. High MELD–Na score may be a useful mortality predictor of SBE in cirrhotic patients.  相似文献   
39.
The present report describes a case of severe airway obstruction caused by endobronchial tuberculosis in an 11-year-old girl who was successfully treated by bronchoscopic balloon dilation. This case illustrates the insidious presentation and the increasingly important role of bronchoscopic intervention in the management of endobronchial tuberculosis. In addition, a brief literature review of the condition in the pediatric age group is included.  相似文献   
40.
The different types of alpha-thalassemia: practical and genetic aspects   总被引:1,自引:0,他引:1  
From May 1985 to October 1987, 1,564 Southeast Asians living in Hawaii were screened for hereditary anemias. Microcytosis was determined by electronic red cell indices and morphology; iron deficiency was ruled out by normal red cell distribution width and normal protoporphyrin levels; Hb E was determined by electrophoresis; beta-thalassemia (thal) heterozygotes were identified by raised Hb A2 on column chromatography. alpha-Thalassemia heterozygotes were diagnosed by exclusion. Family studies helped identify or confirm diagnoses, especially for the alpha-thal-2 heterozygotes (-alpha/alpha alpha) and homozygotes (-alpha/-alpha). Provisional diagnoses are being checked by DNA analyses. Iron deficiency prevented detection of possibly coexisting alpha-thalassemias in 97 individuals. Technical problems included the obscuring of standard criteria for recognizing the alpha-thal variants by the presence of Hb E or beta-thal. In such cases, alpha-thal could only be detected by family studies or DNA analyses. Problems with hemoglobin (Hb) electrophoresis included Hb H migrating beyond the edge of the strip if incubation was not closely monitored, and difficulty in detecting the small amounts of unstable Hb Constant Spring. DNA analyses also had limitations, since the nondeletion alpha-thalassemias would not be detected by routine Southern blotting. DNA analyses suggested that about 50% of presumed alpha-thalassemias were alpha-thal-2 (-alpha/alpha alpha) variants, and a corresponding number of alpha-thal-2 variants were among the apparent normals. Gene frequencies in the unselected Lao subjects were approximately 0.2 for Hb E, at least 0.1 for (-alpha), usually a rightward (alpha -3.7) type, 0.04 for (-), and 0.01 for a beta-thal. Multistep screening for the alpha- and beta-thalassemias was an effective and efficient strategy.  相似文献   
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