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41.
GC—MS法鉴定银柴胡挥发油的化学成分   总被引:5,自引:0,他引:5  
目的 研究银柴胡的挥发油化学成分。方法 采用气相色谱-质谱联用仪(GC-MS)对银柴胡的挥发油化学成分进行了分析鉴定。结果 从分离出的20多个峰中鉴定出17个化学成分。结论 银柴胡挥发油的主要化学成分为2-甲基-5-异丙烯基-2,5-己二烯-1-乙酸酯,去乙酰基蛇形毒素和14-甲基十五烷酸甲酯等成分。  相似文献   
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目的:探讨薄荷油腹部湿热敷对维持性血液透析患者便秘的疗效。方法将60例维持性血液透析便秘患者随机分为观察组与对照组各30例,观察组患者采用薄荷油腹部湿热敷,对照组给予番泻叶3~6 g泡水顿服,疗程均为2周。观察2组患者的疗效及排便时患者的反应。结果观察组总有效率明显高于对照组,2组比较差异有统计学意义(P〈0.05)。结论薄荷油腹部湿热敷操作简单,无副作用,不仅可以使维持性血液透析患者保持大便通畅,而且可以减少因便秘引起的不适和并发症,进而提高患者的生活质量。  相似文献   
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We explored the physiological effects of inhaling basil essential oil (BEO) and/or linalool and identified odor-active aroma compounds in BEO using gas chromatography/mass spectrometry (GC–MS) and GC–olfactometry (GC–O). Linalool was identified as the major volatile compound in BEO. Three groups of rats were administered BEO and linalool via inhalation, while rats in the control group were not. Inhalation of BEO for 20 min only reduced the total weight gain (190.67 ± 2.52 g) and increased the forced swimming time (47.33 ± 14.84 s) compared with the control group (219.67 ± 2.08 g, 8.33 ± 5.13 s). Inhalation of BEO for 5 min (392 ± 21 beats/min) only reduced the pulse compared with the control group (420 ± 19 beats/min). Inhalation of linalool only reduced the weight of white adipose tissue (5.75 ± 0.61 g). The levels of stress-related hormones were not significantly different among the groups. The total cholesterol and triglyceride levels decreased after inhalation of BEO for 20 min (by more than −10% and −15%, respectively). Low-density lipoprotein cholesterol levels were lowered (by more than −10%) by the inhalation of BEO and linalool, regardless of the inhalation time. In particular, BEO inhalation for 20 min was associated with the lowest level of low-density lipoprotein cholesterol (53.94 ± 2.72 mg/dL). High-density lipoprotein cholesterol levels increased after inhalation of BEO (by more than +15%). The atherogenic index and cardiac risk factors were suppressed by BEO inhalation. Animals exposed to BEO and linalool had no significant differences in hepatotoxicity. These data suggest that the inhalation of BEO and linalool may ameliorate cardiovascular and lipid dysfunctions. These effects should be explored further for clinical applications.  相似文献   
45.
目的 :探讨豆油 [富含 ω- 6多不饱和脂肪酸 ( PUFAs) ]对饲低硒粮大鼠血浆 Cu、Zn、Ca和 Mg含量变化的影响。方法 :用低硒和补硒饲料喂养大鼠 4周 ,补加 5 %豆油后再继续饲养 4周。用原子吸收分光光度计测定大鼠血浆中 Cu、 Zn、 Ca、和 Mg含量。结果 :饲低硒粮和补硒粮组 ,在饲料中添加豆油后 ,大鼠血浆中 Cu、Zn、Ca、和 Mg含量均有不同程度下降。在添加豆油的大鼠 Zn、Mg含量下降更明显 ,Ca、Cu含量虽有所下降 ,但差异无显著性。结论 :饲料中添加豆油 ,使大鼠PUFAs的摄入量增加 ,Cu、Zn、Ca和 Mg含量降低。  相似文献   
46.
The single light oil regenerating agent has certain limitations on the performance recovery of aged asphalt. In this study, tung oil, dioctyl phthalate (DOP), C9 petroleum resin, and organic montmorillonite (OMMT) were used to prepare the composite regenerating agent, and its optimal mix proportion was determined by the orthogonal experimental design. The rheological properties and anti-aging performance of reclaimed asphalt were studied by the dynamic shear rheometer (DSR) and bending beam rheometer (BBR); and the Fourier transform infrared (FTIR) spectrometer, gel permeation chromatography (GPC), and scanning electron microscope (SEM) were adopted to explore its microstructure, morphology, and mechanism of action. The results show that with the addition of tung oil composite regenerating agent, the rheological properties of aged asphalt can be effectively recovered, even better than that of base asphalt. By using the complex modulus aging index (CMAI) and phase angle aging index (PMAI) it is found that the anti-aging performance of reclaimed asphalt is better than that of base asphalt. With the optimal content of the tung oil composite regenerating agent, the contents of characteristic functional groups and macromolecular asphaltenes in the aged asphalt can be reduced, indicating that the composite regenerating agent is beneficial to the dispersion and dissolution of polar substances in the aged asphalt. After aging, a large number of wrinkles appear on the surface of the asphalt. However, the addition of the tung oil composite regenerating agent can make the asphalt surface smooth, which indicates that the tung oil composite regenerating agent can restore the microstructure and morphology of aged asphalt to a certain extent.  相似文献   
47.
Fish oil supplementation is suggested as possible mean to improve neurological manifestations of chronic diseases and cytokine immunotherapies. Preclinical and clinical studies show that fish oil supplementation seems able to reduce disease-associated anorexia and body weight loss. This improvement could be due to shifts in metabolism and changes in proinflammatory cytokine production and action. ω-3 Polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid, are used as substrates for eicosanoid synthesis, competing for enzymes with arachidonic acid, which is a substrate for the synthesis of proinflammatory immunomodulators, such as prostaglandin E2. Fish oil supplementation is generally found to lower production of cytokines including interleukin-1 and tumor necrosis factor-α, thereby reducing various immune responses, including inflammation. However, conflicting results regarding the effects of fish oil interventions have been reported. The main factor that emerges from the contradictory reports is the variety of models, assays and methodologies that have been used. This brief review presents an overall perspective on the potential use of ω-3 PUFAs as a nutritional intervention to ameliorate disease-associated and cytokine-induced neurological manifestations. We conclude that substantial further research is required to understand the exact nature of n-3 PUFA-induced immunomodulation in health and disease.  相似文献   
48.
An experimental and theoretical methodology is proposed to calculate the permeability of microcapsules that contain a core of oil-based active ingredient. Theoretical analysis is performed considering the polydispersity of the measurable capsule size, which allows the estimation of the permeability polydispersity via three different methods. The models proposed were applied in order to determine the permeability of melamine-formaldehyde microcapsules with hexyl salicylate as core oil. Release experiments were performed with four different co-solvents (ethanol, propan-1-ol, propan-2-ol and 1,3-butanediol) of different concentration. Permeability values were found to be constant, despite a two order magnitude of difference in the solubility concentrations.  相似文献   
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Objective: To evaluate the efficacy and safety of essential oil treatment for type Ⅲ chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS). Methods: A randomized controlled trial was conducted from December 2014 to October 2015. Seventy type Ⅲ CP/CPPS patients were assigned to the essential oil group(35 cases) or almond placebo oil control group(35 cases) by a random number table. The oil was smeared by self-massage on the suprapubic and sacral region once a day for 4 weeks. The National Institutes of Health Chronic Prostatitis Syndrome Index(NIH-CPSI) and expressed prostatic secretions(EPS) were examined. The primary outcome was NIH-CPSI pain domain. The secondary outcomes included other NIH-CPSI domains and laboratory examinations of EPS. Adverse events were also observed. Results: Sixty-six subjects completed the full 4-week treatment. There was no significant difference between almond oil control and essential oil groups in terms of the total score of NIH-CPSI, pain, quality of life and urination domain scores of NIH-CPSI and EPS examinations(P0.05). In the essential oil group, pain between rectum and testicles(perineum) in the domain of pain or discomfort was significantly reduced at week 2 and week 4 compared with almond oil control group(P0.01). No serious adverse events occurred. Conclusion: The essential oil may reduce the pain or discomfort in the perineum region in patients with CP/CPPS.  相似文献   
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