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目的 在“药辅合一”理念下导入Pickering乳技术,提升儿科用药羚珠散中石菖蒲挥发油的稳定性。方法 对羚珠散各饮片粉末进行初步表征,确定稳定剂。通过成乳量、包油量和乳剂形态筛选出最佳稳定剂质量浓度、油水比和制备方法。并使用近红外光谱(nearinfraredspectroscopy,NIRS)分析石菖蒲油在Pickering乳中的包裹状态。比较不同时间下各组别挥发油的保有量、丙二醛和过氧化物的含量。再通过GC-MS分析其中成分的变化趋势。结果 筛选出珍珠粉作为Pickering乳的稳定剂,珍珠粉质量浓度为65 mg/mL,油水比9∶11为最优成乳条件,高压均质法为最优的制备方法,NIRS分析可知石菖蒲挥发油被珍珠粉包裹,Pickering乳液中没有形成新的化学键。对比各组在不同时间段下石菖蒲油的保有率和其中丙二醛和过氧化物含量,可知40℃放置1、3、8 h的Pickering乳剂相比于石菖蒲挥发油组有更高的保有率和更低的氧化程度。GC-MS分析结果表明,相比于石菖蒲挥发油组,Pickering乳组挥发性成分的稳定性显著提高。结论 在“药辅合一”理念下Pickering乳可用于含油固... 相似文献
33.
目的 采用便携式近红外(near infrared,NIR)光谱仪建立东阿阿胶鉴别分析模型,并优选出特征波段。方法 采用BWS903型NIR光谱仪和microPHAZIRTMRX型NIR光谱仪2款便携式光谱仪采集了47份阿胶样品的光谱,并采用软独立建模聚类分析(soft independent modeling class analog,SIMCA)和偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)等化学计量学算法,建立了东阿阿胶的判别分析模型。结果 所建立模型能够准确区分东阿阿胶和其他品牌阿胶。在此基础上,采用相关系数法优选出BWS903光谱特征波长为1300~1380 nm和1460~1540 nm;microPHAZIRTMRX光谱特征波长为1600~1680 nm和2160~2240 nm,上述波段分别代表-NH2和-CONHR肽键的1级倍频吸收,这些波段可作为东阿阿胶的特征波段,并可据此设计专用型、小型化的NIR光谱仪,用于东阿阿胶的品牌... 相似文献
34.
Reliability of erector spinae oxygenation and blood volume responses using near-infrared spectroscopy in healthy males 总被引:1,自引:1,他引:1
The purpose of this investigation was to (1) describe the trends in oxygenation (OXY) and blood volume (BV) of the right and left paraspinal muscles during the Biering-Sorensen muscle endurance (BSME) test using near infrared spectroscopy (NIRS), and (2) assess the test-retest reliability of OXY and BV changes during the BSME in healthy males. Seventeen healthy males [age=28.4 (9.8) years, height=1.75 (0.05) m, body mass=82.7 (9.1) kg; mean (SD)] completed two BSME trials within 1 week. NIRS probes were placed bilaterally at lumbar 3. The test was performed with the subject in the prone position using the following protocol: 2 min baseline, BSME, and 4 min recovery. The delta and range values of OXY and BV were used for analysis. Acceptable intra-class correlations were observed for endurance time and all the NIRS variables at the point of fatigue and at each 10% segment of the BSME during the two trials. Bland-Altman plots confirmed the reproducibility of the bilateral NIRS responses of the paravertebral muscles. The BV responses were more reliable than the OXY responses during the two trials. The OXY and BV responses of the paravertebral muscles during static contractions can be measured reliably using NIRS. Future studies should focus primarily on BV for analysis. 相似文献
35.
目的:观察810nm半导体红外线激光经巩膜睫状体光凝术(transchera ciliary photocoagnlation TSCPC)治疗难治性青光眼的临床效果。方法:应用法国BIV公司生产的810nm半导体红外线激光仪,经光纤将能量传输到激光头,在距角膜缘后1.2~1.5mm,紧贴眼球壁,使激光头与视轴平行,设置激光能量1.8~2.2W,时间2~3s,发射激光后听到眼内“爆破声”作为治疗能 相似文献
36.
目的 探讨多功能红外治疗宫颈糜烂的疗效。方法 将 171例宫颈糜烂患者随机分为两组 ,治疗组用多功能红外治疗仪探头点状光凝子宫颈 ,每点 2~ 3秒 ,对照组用CO2 激光治疗。结果 治疗组治愈 84例 ,占 97.67% ,对照组治愈 73例 ,占 85.88% ,两组疗效比较P <0 .0 5。结论 采用多功能红外治疗仪治疗宫颈糜烂疗效明显优于对照组。 相似文献
37.
Photoacoustic Fourier transform infrared (PA-FT-IR) depth profiling spectra of the enamel of an intact human tooth are obtained in a completely nondestructive fashion. The compositional and structural changes in the tissue are probed from the enamel surface to a depth of about 200 m. These changes reflect the state of tissue development. The subsurface carbonate gradient in the enamel could be observed over the range of about 10–100 m. The carbonate-to-phosphate ratio increases in the depth profile. The depth profile also reveals changes in the substitutional distribution of carbonate ions. Type A carbonates (hydroxyl substituted) increase relative to type B carbonates (phosphate substituted) with increasing thermal diffusion length. In addition to the changes in the carbonate ion distribution and content, the PA-FT-IR depth profile clearly indicates a dramatic increase in the protein content relative to the phosphate content with increased depth. The changes in the carbonate content and distribution, along with the changes in the protein content, may be responsible for the changes observed in the apatitic structure in the depth profile of the enamel. 相似文献
38.
Durrer Carlo Irache Juan Manuel Puisieux Francis Duchêne Dominique Ponchel Gilles 《Pharmaceutical research》1994,11(5):674-679
A Fourier transform infrared spectroscopy/attenuated total reflection technique for direct quantification of adsorbed poly(styrene) latexes on rat intestinal mucosa was developed for deposited latex amounts up to 1.5 g/m2. The method agreed well with another dosage assay of adsorbed particles by turbidimetry after denaturation of the mucus. Adsorption kinetics were made under static conditions at latex concentrations of 4 g/L in physiological saline. Ninety percent of equilibrium was reached after 10 min for a particle size of 230 nm, 20 min for a size of 320 nm, and 30 min for a size of 670 nm. The plateaus were between 0.6 and 0.9 g/m2 (adsorbed mass per apparent surface of mucosa). The first phase of the kinetics was theoretically approached by a diffusion model in the suspension medium. Mucosa from rat jejunum and ileum could be considered as a homogeneous biological model for latex adsorption. 相似文献
39.
The effects of unilateral sciatic neurectomy (USN) on the development of the femur were studied in 15 growing Wistar-derived
rats (age, 5 weeks). The rats were divided into four groups: USN-operated group (right femur), USN-nonoperated group (left
femur), sham-operated group (right femur), and sham-nonoperated group (left femur). Bone mineral density (BMD), bone mineral
content (BMC), bone area, periosteal circumference, and endosteal circumference were measured by peripheral quantitative computed
tomography (pQCT) and the mineral/matrix ratio was evaluated by Fourier transform infrared spectroscopy (FTIR). The USN-operated
group showed a significant decrease in cortical BMC, bone area, and periosteal circumference compared with the other groups
(P < 0.05). The cortical BMD did not vary significantly between the groups. In the cancellous bone, the USN-operated group showed
a significant decrease in BMD and BMC at the metaphysis compared with the other groups (P < 0.05). The mineral/matrix ratio of the cortical bone did not differ significantly between the USN-operated and USN-nonoperated
groups. These results suggest that in cortical bone, USN inhibits periosteal bone formation but has no significant effect
on the mineral/matrix ratio of cortical bone in femurs. In cancellous bone, USN induces bone loss at the metaphysis.
Received: Nov. 19, 1998 / Accepted: Feb. 12, 1999 相似文献
40.