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51.
不同种植基地滇重楼根茎中甾体皂苷有效成分差异的研究   总被引:1,自引:0,他引:1  
目的:探讨不同种植基地滇重楼根茎中甾体皂苷有效成分的差异。方法:采用超高效液相色谱法(UHPLC)测定不同种植基地滇重楼根茎中重楼皂苷Ⅰ、Ⅱ、Ⅵ、Ⅶ及总皂苷的含量,并用液质联用(LC-MS)技术定性分析其甾体皂苷有效成分的差异。结果:不同种植基地滇重楼根茎中重楼皂苷Ⅰ及总皂苷含量差异较小,重楼皂苷Ⅱ、Ⅵ、Ⅶ含量差异较大;重楼皂苷Ⅰ、重楼皂苷Ⅲ(薯蓣皂苷)、重楼皂苷Ⅴ、重楼皂苷Ⅶ是不同种植基地滇重楼根茎中甾体皂苷的主要存在形式,不同种植基地滇重楼根茎中重楼皂苷Ⅱ、重楼皂苷H、重楼皂苷Ⅵ、纤细薯蓣皂苷差异较大;根据不同种植基地滇重楼根茎正离子模式下液质数据的主成分分析(PCA)模型可将其分为四类。结论:不同种植基地滇重楼根茎中重楼皂苷Ⅰ、Ⅱ、Ⅵ、Ⅶ及总皂苷的含量、甾体皂苷有效成分及化学成分种类差异较大。  相似文献   
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重楼(PPS)为百合科重楼属多年生草本植物,具有清热解毒,消肿止痛,凉肝定惊的作用。重楼中无机元素种类和含量对重楼的药理作用和临床疗效有不同程度的影响。重楼中无机元素含量测定常用的方法有等离子体原子发射光谱法(ICP-AES)、火焰原子吸收分光光度法(FAAS)、微波消解-火焰原子吸收法等。重楼中无机成分分布与来源、产地、培育条件等有关。土壤中无机元素的种类和含量对重楼的生长发育有不同的影响。药理作用研究证实重楼中无机元素如Ca、K、Fe、Mg等在疾病治疗方面具有一定作用。  相似文献   
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Background

There are two philosophical approaches to planning liver resection for malignancy: one strives towards zero postoperative mortality by stringent selection of candidates, thus inherently limiting patients selected; the other, accepts a low yet definite postoperative mortality rate, and offers surgery to all those with potential gain in survival. The aim of this study was to retrospectively analyse an alternative and evolving strategy, and its impact on short-term outcomes.

Method

3118 consecutive hepatectomies performed in 2627 patients over 3 decades (1980–2011) were analysed. Patient demographics, tumour characteristics, operative details, and postoperative outcomes were analysed.

Results

1528 patients (58%) were male. Colorectal liver metastases (1221 patients, 47%) and hepatocellular carcinoma (584 patients, 22%) were the most common diagnoses. Anatomical resections were performed in 2045 (66%), some form of vascular clamping was used in 2385 (72%), and blood transfusion was required in 1130 (36%) patients. Use of preoperative techniques to increase feasibility and safety of complex liver resections allowed expansion of indications to include sicker patients with larger tumours in the later period of the study. Overall morbidity and mortality rates were 31% and 3% respectively. During the first vs. second half of the study period the postoperative morbidity and mortality were 19% vs. 36% (p < 0.001) and 2% vs. 4% (p = 0.006) respectively.

Conclusion

With increasing experience, more patients were accepted for complex hepatectomies. However, there was a definite yet contained increase in postoperative morbidity and mortality.  相似文献   
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Low-carbon diets can counteract climate change and promote health if they are nutritionally adequate, affordable and culturally acceptable. This study aimed at developing sustainable diets and to compare these with the EAT-Lancet diet. The Swedish national dietary survey Riksmaten Adolescents 2016–2017 was used as the baseline. Diets were optimized using linear programming for four dietary patterns: omnivores, pescatarians, vegetarians and vegans. The deviation from the baseline Riksmaten diet was minimized for all optimized diets while fulfilling nutrient and climate footprint constraints. Constraining the diet-related carbon dioxide equivalents of omnivores to 1.57 kg/day resulted in a diet associated with a reduction of meat, dairy products, and processed foods and an increase in potatoes, pulses, eggs and seafood. Climate-friendly, nutritionally adequate diets for pescatarians, vegetarians and vegans contained fewer foods and included considerable amounts of fortified dairy and meat substitutes. The optimized diets did not align very well with the food-group pattern of the EAT-Lancet diet. These findings suggest how to design future diets that are climate-friendly, nutritionally adequate, affordable, and culturally acceptable for Swedish adolescents with different dietary patterns. The discrepancies with the EAT diet indicate that the cultural dietary context is likely to play an important role in characterizing sustainable diets for specific populations.  相似文献   
56.
BackgroundThe massive weight loss induced by bariatric surgery is associated with major benefits, but the effect on semen variables is still uncertain.ObjectivesTo explore semen modifications with gastric bypass and sleeve gastrectomy.SettingFive French University Hospitals.MethodsMale candidates for bariatric surgery with no history of infertility were recruited in this controlled prospective study. Sperm characteristics were collected before surgery and then 6 months and up to 12 months after surgery.ResultsForty-six adult men who underwent gastric bypass (n = 20) or sleeve gastrectomy (n = 26) were included. Total sperm count tended to be lower at 6 months and showed a significant decrease at 12 months in both surgery groups, at ?69.5 million (?96.8 to ?42.2 million; P = 0.0021). Total sperm count at 12 months relative to baseline was ?41.4 million (P = .0391) after gastric bypass and ?91.1 million (P = .0080) after sleeve gastrectomy. This was counterbalanced by an associated resolution of hypogonadism and decrease of DNA fragmentation in most patients with time after surgery.ConclusionImprovement in some semen variables after bariatric surgery observed in 3 previous studies is in contrast to the lower mean total sperm count found in this study at 1 year. The possible reversibility of this effect in the long term and the impact of surgery on fertility both remain unknown.  相似文献   
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