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51.
用气相色谱法分析了小鼠眼球中脂肪酸的组成及百分含量。分离是在25m×0.25mmPEG-20M熔融石英毛细管柱内进行,眼球中12种主要饱和及不饱和脂肪酸得到了定性和定量。本实验可为有关眼疾病的治疗、预防及生化方面的深入研究提供有意义的信息。 相似文献
52.
目的:研究术前使用呼吸机无创正压通气治疗对脊柱侧凸患者围手术期肺功能的影响。方法:将40例Cobb角≥60°、肺功能存在中度以上限制性通气功能障碍、行脊柱侧凸矫形术的脊柱侧凸患者,随机分成A组和B组,每组20例。A组在术前采用BiPAP呼吸机,经用面罩无创正压通气(NIPPV)治疗1个月;B组常规术前准备。观察A组患者治疗前后肺功能的改善及两组患者围手术期肺功能的差异。结果:两组患者性别、年龄、身高、体重、Cobb角度、手术时间、手术径路、融合椎体数等基本情况比较无统计学差异(P>0.05);A组患者经NIPPV治疗后肺活量(VC)、肺活量占预计值的百分比(VC%)、用力肺活量(FVC)、第一秒最大呼气量(FEV1.0)、最大通气量(MVV)和最大通气量占预计值的百分比(MVV%)较治疗前明显改善(P<0.01);两组患者术中氧合指数、术后拔管时间、拔管后15min动脉血气PO2、PCO2比较有显著性差异(P<0.05)。结论:术前无创正压通气治疗可改善脊柱侧凸患者围手术期的肺功能,可缩短手术后气管插管的拔管时间,改善术后通气功能,有助于脊柱侧凸患者手术后早期恢复。 相似文献
53.
目的:探讨舒芬太尼全凭静脉复合麻醉时对听觉诱发电位指数、血流动力学和术后复苏的影响.方法:40例美国标准协会(ASA)Ⅰ~Ⅱ级病人择期行胆囊切除手术,随机分为Ⅰ组(舒芬太尼组)和Ⅱ组(芬太尼组),记录两组病人麻醉期间各时间点的听觉诱发电位指数(AEPI)值、收缩压、舒张压、心率和SpO2.结果:Ⅱ组插管后1 min、2 min的收缩压较Ⅰ组升高,而插管后1 min的心率较Ⅰ组降低(P<0.05);Ⅰ组插管后1 min、2 min和3 min时的AEPI值低于Ⅱ组(P<0.05);Ⅰ组拔管后至定向力恢复的时间较Ⅱ组长(P<0.05);Ⅰ组丙泊酚的用量较Ⅱ组少(P<0.05).结论:等效剂量的舒芬太尼较芬太尼的全凭静脉复合麻醉可以使病人达到更为合适的麻醉深度,并能使血流动力学更加稳定,同时可减少丙泊酚用量. 相似文献
54.
55.
Camus Kar Man Choy Pauline Cho Wai-Yuen Chung Iris F F Benzie 《Optometry and vision science》2003,80(9):632-636
BACKGROUND: Tear ascorbate is important for corneal health. A rapid and simple method for measurement of ascorbate in tears is needed, and adequate knowledge of physiological variation of tear ascorbate is important to facilitate comparative studies of the effect of, for example, contact lens wear and environmental conditions and stresses. However, there are currently no data on physiological variation of tear ascorbate. This study validated a simple and speedy method for tear ascorbate and investigated between-eye and between-day variation in tear ascorbate in healthy young adults. METHODS: Yawn-induced reflex tears were collected from 32 healthy Hong Kong Chinese subjects and measured by both high-performance liquid chromatography (HPLC) and by an enzyme-linked colorimetric method known as FRASC (total ferric reducing (antioxidant) activity and ascorbate concentration measurement). For between-eye variation, yawn reflex tears were collected from each eye of the same 32 healthy subjects, and ascorbate was measured using HPLC; in a separate experiment for between-day variation, tears were collected on two separate days from 14 subjects, and ascorbate was measured by FRASC. RESULTS: Both HPLC and FRASC showed high precision, and results obtained using FRASC were not statistically different from those using HPLC; mean +/- SD were, respectively, 18.5 +/- 4.4 microM and 18.5 +/- 4.8 microM for HPLC and FRASC methods (p = 0.943). No significant between-eye difference in tear ascorbate was found (p = 0.386), and no significant between-day variation was found overall: mean +/- SD ascorbate was 20.0 +/- 6.2 microM on day 1 and 19.3 +/- 6.8 microM on day 2 (p = 0.772). However, between-day variation was large in seven of 14 subjects. CONCLUSION: FRASC is an acceptable alternative to HPLC for measurement of tear ascorbate. Tears for ascorbate investigation can be collected from either eye or, if necessary, from both eyes and pooled. However, tear ascorbate may vary widely from day to day in the same individual. The reasons for this variation require further study but may relate to differences in ascorbate supply or demand within the precorneal tear layer. 相似文献
56.
57.
目的 探讨思维图结合混合式教学对提高《药用植物学》教学质量的价值研究。方法 选取学习《药用植物学》课程的102名学生作为研究对象,其中对照组为2020级51名学生予以常规教学,观察组为2021级51名学生予以思维图结合混合式教学。评估两组学生的考试成绩、评判性思维能力评分、自主学习能力评分及学生对教学质量的反馈。采用SPSS 22.0进行t检验和卡方检验。结果 相较于对照组,观察组学生的考试成绩更高(t=3.01、3.14;P=0.003、0.002);与实践前比较,实践后两组学生的评判性思维能力评分、自主学习能力评分均上升,且观察组高于对照组(t=11.22、2.69;P<0.001、P=0.008);观察组学生对教学质量的反馈高于对照组(t=6.79、7.83、7.26、7.43、8.54;P=0.009、0.005、0.007、0.006、0.003)。结论 思维图结合混合式教学可以提高学生的成绩,改善其评判性思维能力及自主学习能力,学生认为该教学有利于提升教学效果。 相似文献
58.
The Indian population can be divided broadly into Dravidians and the Aryans. In this report, we have attempted to analyze the HLA genetic profile of 400 native North Indian Hindus of Aryan descent. The gene frequencies of a majority of class I and II antigens show similarity to the Caucasoid population. An interesting finding was a complete lack of antigen B14 while B16 and B41 occurred with the least frequency. Haplotype A10, B8 with significant positive linkage disequilibrium as well as showing the highest incidence is characteristic of North Indians. 相似文献
59.
Treatment of motoneuron degeneration by intracerebroventricular delivery of VEGF in a rat model of ALS 总被引:18,自引:0,他引:18
Storkebaum E Lambrechts D Dewerchin M Moreno-Murciano MP Appelmans S Oh H Van Damme P Rutten B Man WY De Mol M Wyns S Manka D Vermeulen K Van Den Bosch L Mertens N Schmitz C Robberecht W Conway EM Collen D Moons L Carmeliet P 《Nature neuroscience》2005,8(1):85-92
Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general. 相似文献
60.
Kam KM Luey CK Tsang YM Law CP Chu MY Cheung TL Chiu AW 《Journal of clinical microbiology》2003,41(10):4502-4511
Two hundred twenty isolates of Vibrio cholerae O1 and O139 collected from 1994 to 2002 in Hong Kong were analyzed by pulsed-field gel electrophoresis (PFGE). Chromosomal DNAs from all V. cholerae isolates in agarose plugs were digested with the restriction enzyme NotI, resulting in 20 to 27 bands. Sixty distinctive PFGE patterns in the range of 10 to 300 kb were noted among 213 isolates typeable by PFGE. By comparing the common PFGE patterns obtained from four well-defined outbreaks of V. cholerae O1 and O139 with those obtained from other, epidemiologically unrelated isolates during the study period, indistinguishable and similar PFGE patterns were identified, indicating their close relatedness, in agreement with the results of epidemiological investigations. Heterogeneous PFGE patterns (with four to six banding differences), however, were identified among strains that were imported from other parts of Asia, including Indonesia, India, and Pakistan. Correlations with epidemiological information further support the usefulness of PFGE as an epidemiological tool in laboratory investigations of suspected outbreaks. Standardization of PFGE methodology will allow international comparison of fingerprint patterns and will form the basis of a laboratory network for tracking V. cholerae. 相似文献