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适宜性产区能够保障傣族药的品质,然而有关植物类傣族药适宜生态因子及适宜产区的研究目前较为匮乏。本研究利用中药材产地适宜性分析地理信息系统(GMPGIS)对植物类傣族药进行全国产地生态适宜性分析,首次提出了植物类傣族药主要分布区域的生态因子范围和主要土壤类型,如年均温8. 6~23. 7℃,年均降水量1 212~1 881 mm,年均日照149. 7~157. 4 W·m-2,主要土壤类型为强淋溶土、冲积土、高活性强酸土等。以179个采样点为基础,通过生态相似性分析得到植物类傣族药在全球范围内的最大生态相似度区域,主要包括中国、巴西、美国、缅甸、老挝等国家。在中国主要集中在云南的西部和南部,包括西双版纳傣族自治州、德宏傣族景颇族自治州普洱市、保山市、临沧市具有较大的适宜栽培区域。除此之外,本文通过分析傣族药人才匮乏、傣族药资源日益减少、文化传承具有局限性、科学研究薄弱等问题,并提出了通过傣族医药高素质人才培养、傣族药资源调研和保护工作、推进傣族药资料古籍的搜集整理、加强傣族药基础研究和应用研究等策略促进傣族医药发展。本研究为指导植物类傣族药生产基地合理布局、引种繁育等提供依据,为高品质傣族药的科学规范化生产奠定基础。  相似文献   
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BackgroundUsing a mobile phone while performing a postural and locomotor tasks is a common, daily situation. Conversing or sending messages (SMS) while walking account for a significant share of accidental injuries. Therefore, understanding the consequences of using a mobile phone on balance and walking is important, all the more so when these postural and locomotor tasks are aggravated by a disease.Research questionOur objective was to conduct a scoping review on the influence of a dual-task situation – generated by the use of mobile phone – on users' postural and/or locomotor tasks.MethodsThe literature search was conducted in English on PubMed/Medline and CINHAL databases, using keywords associated with postural and locomotor tasks and with the use of mobile phone. Study location, population, number of subjects, experimental design, types of phone use, evaluated postural-locomotor tasks and expected effects were then analyzed.Results and significance46 studies were included in this work, 24 of which came from North America. All studies compared postural and locomotor tasks with and without the use of a smartphone. Ten studies also compared at least 2 groups with different characteristics. Only 4 studies included pathological subjects. Various modalities were tested, and most studies focused on walking. Results show that the use of smartphones slows down movement and induces a systematic imbalance, except when listening to music. The dual task of "using the smartphone during a postural or locomotor tasks" induces systematic disturbances of balance and movement, which must be taken into account in the rehabilitation approach. Future studies will have to extend the knowledge regarding pathological situations.  相似文献   
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目的建立单抗N糖分析方法的系统适用性对照品,并设定相应的系统适用性要求。方法利用液质联用(LC-MS)仪对N糖系统适用性对照品进行N糖型的表征鉴别,并对对照品进行稳定性评价。结合方法特点和验证数据,对系统适用性要求进行设定。结果建立的系统适用性对照品具有良好的稳定性,其糖型涵盖了单抗主要的N糖型种类。针对3种药典拟收录的单抗N糖分析方法,设定了以下系统适用性要求,包括:图谱与典型图谱相似、G1F(1,6)和G1F(1,3)的分离度应满足具体要求、G0F%应在规定的范围内、G0F保留时间的RSD应≤4%。结论建立了单抗N糖系统适用性对照品,可配合3种2020年版《中国药典》拟收录的N糖分析方法使用。  相似文献   
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Risedronate is a nitrogen-containing bisphosphonate for the treatment and prevention of postmenopausal osteoporosis. The current work aims to develop a novel green HPLC-UV method for the rapid analysis of risedronate sodium in bulk and tablet formulation. The analyzed samples were separated on Waters Atlantis dC18 (150 mm × 3.9 mm; 5 μm) column using a green mobile phase consisting of potassium phosphate buffer pH 2.9 and potassium edetate buffer pH 9.5 in a ratio of 1:2, the final pH was adjusted to 6.8 with phosphoric acid, the mobile phase was pumped at a rate of 1.0 mL/min, with column temperature set at 30 °C, eluted samples were detected at 263 nm and the chromatographic run time was 3.0 min. The method was found to be linear over the concentration range of 14–140 μg/mL with a correlation coefficient (r2) of 0.9994. Accuracy and precision were evaluated from three QC samples (LQC, MQC and HQC) together with the five calibrators where the percentage accuracy was found to be 101.84%. Processed quality control samples of risedronate sodium were tested for stability at different conditions, short term, long term and freeze- thaw stability. The current method was further extended to study the content uniformity of Actonel® tablets following United States Pharmacopoeia (USP) guidelines. The proposed method was fully validated as per ICH guidelines.  相似文献   
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Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
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目的 远志主产东北、华北、西北和华中地区以及四川省,不同产地的药用植物远志有明显质量差异,且远志的栽培区较为集中,在全国范围内针对远志的适宜性区划研究较少,为确定全国范围内的远志适宜区划,根据远志采样点所分布区域的生态因子,对全国范围内远志的生境适宜性进行评价分析。方法 运用MaxEnt模型筛选出影响远志生境分布的生态因子,构建评价模型,利用ArcGIS软件对远志的生境进行适宜性评价,得到全国范围内远志生境的高适宜区、中适宜区、低适宜区和不适宜区。结果 评价模型精度较高,得出远志在我国的适宜性分布区面积为3.21×106 km2,其中高适宜区面积为0.52×106 km2;中适宜区面积为0.96×106 km2;低适宜区面积为1.73×106 km2。高适宜区主要分布在山西省、河北省、山东省、陕西省、辽宁省和河南省。影响远志分布的主要生态因子有年均温变化范围、最干季度平均温度、最湿季度降水量、海拔、坡度、上层(0~30 cm)碳酸盐或石灰含量。结论 研究结果与相关文献的记载较为吻合,可为中药远志的野生资源保护与栽培种植提供理论参考。  相似文献   
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The dietary specialist fruit fly Drosophila sechellia has evolved resistance to the secondary defence compounds produced by the fruit of its host plant, Morinda citrifolia. The primary chemicals that contribute to lethality of M. citrifolia are the medium‐chain fatty acids octanoic acid (OA) and hexanoic acid. At least five genomic regions contribute to this adaptation in D. sechellia and whereas the fine‐mapped major effect locus for OA resistance on chromosome 3R has been thoroughly analysed, the remaining four genomic regions that contribute to toxin resistance remain uncharacterized. To begin to identify the genetic basis of toxin resistance in this species, we removed the function of well‐known detoxification gene families to determine whether they contribute to toxin resistance. Previous work found that evolution of cytochrome P450 enzymatic activity or expression is not responsible for the OA resistance in D. sechellia. Here, we tested the role of the two other major detoxification gene families in resistance to Morinda fruit toxins – glutathione‐S‐transferases and esterases – through the use of the pesticide synergists diethyl maleate and tribufos that inhibit the function of these gene families. This work suggests that one or more esterase(s) contribute to evolved OA resistance in D. sechellia.  相似文献   
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Tick‐borne diseases (TBDs) have a large impact on animal health and the livelihood of livestock owners, particularly in developing countries. Although climatic and ecological conditions in Pakistan may favour the transmission of tick‐borne pathogens (TBPs), only a few systematic studies have been carried out on TBPs and the diseases that they cause in this country. To improve our understanding of the distribution of TBPs, 3,807 ticks were collected from ruminants (n = 369) on 108 livestock farms (semi‐arid zone = 36, arid zone = 72) in Punjab Province. After morphological identification ticks were pooled into 405 pools (Hyalomma anatolicum = 300, Rhipicephalus microplus = 89, Hyalomma dromedarii = 9, Rhipicephalus turanicus = 7) based on their species, locality of collection, and the host. DNA from each pool was screened by a Reverse Line Blot (RLB) hybridization assay for the presence of Anaplasma, Ehrlichia, Rickettsia, Babesia, and Theileria species. DNA from at least one TBP was found in 142 (35.1%) pools. Among the positive pools, 91 (64.1%) had a mixed infection with two or more TBPs, whereas 51 (35.9%) pools were infected with a single TBP. The detected pathogens not only included species that were known to be endemic in Pakistan, such as Theileria annulata (6.7%), Theileria orientalis (3.5%), Anaplasma marginale (5.7%), Anaplasma centrale (2.7%), Anaplasma ovis (1.5%), Babesia bigemina (0.7%), and Babesia bovis (0.2%), but also several TBPs that had not been reported to occur in Pakistan before. This included Ehrlichia minasensis (3.2%), an Anaplasma platys‐like organism (1.2%), Babesia occultans (0.2%), and Rickettsia massiliae (0.2%), as well as two previously uncharacterized species: Ehrlichia sp. Multan (18.0%) and Anaplasma sp. (BL099‐6) (2.22%). The pathogenicity of these novel species remains to be examined. This study shows that a much broader spectrum of TBPs is present in Pakistan than previously thought, including several zoonotic pathogens.  相似文献   
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