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41.
渗漉法是将经过处理的药材粉末置于渗漉器中,不断加入溶剂,并收集渗漉液的一种中药常用提取方法,具有设备简单,操作容易,适用药材范围广,能有效提取热不稳定成分或组分等优点,但也存在溶剂消耗量大,提取耗时长,后续浓缩工艺能耗大等不足。该文主要综述了中药渗漉常见设备类型、工艺影响因素、参数优化方法以及过程监测方面的研究进展。分析文献后认为粉末粒度、溶剂组成、浸渍时间、渗漉流速、溶剂用量是渗漉工艺的重要影响因素。目前在渗漉工艺在线监测时采用近红外光谱技术较多,偏最小二乘法是常用的定量建模方法。笔者认为借鉴"质量源于设计"理念进行工艺控制,深入探究渗漉工艺机制并研发工艺控制方法是今后的发展趋势,所以应该深入探索过程建模技术,完善过程优化技术,研发过程监测技术。构建渗漉过程模型时可考虑借鉴柱色谱工艺的机制模型和经验模型。优化渗漉工艺参数时应考虑药材品质变化的影响,也需要研发更加简便易用的方法以监测渗漉过程状态和渗漉液关键性质。  相似文献   
42.
  目的:优化愈骨疗伤片的制备工艺,筛选最优制剂处方。  方法:在考察提取物粒径基础上,以片剂中川续断皂苷溶出量作为考察指标,采用正交试验对搅拌速度、制粒速度和聚维酮K30浆液浓度三者关系进一步考察。采用单因素进一步优选润滑剂和包衣工艺条件。  结果:最佳的愈骨疗伤片处方为提取物颗粒中加入10%乳糖、7.5%羧甲基淀粉钠和2.5%聚维酮K30,以及0.5%硬脂酸镁混合后压片;采用低浓度乙醇包衣液进行包衣。  结论:制得的愈骨疗伤片制剂工艺稳定,包衣后改善了片剂的吸潮性,增加了产品的稳定性,更便于保存和运输。  相似文献   
43.
目的基于网络药理学分析丹参治疗微循环障碍的分子生物学机制。方法借助TCMSP、PubChem Search、Genecards数据库和Swiss target prediction在线工具得到丹参的活性成分治疗微循环障碍的作用靶标,利用Cytoscape 3.3.0软件构建丹参活性成分-微循环障碍作用靶标网络,通过STRING数据库构建靶蛋白相互作用(PPI)网络,通过生物学信息注释数据库(DAVID)进行基因本体(GO)生物学过程和京都基因与基因组百科全书(KEGG)通路富集分析。结果从丹参中共筛选出治疗微循环障碍的65个相关活性成分,并发现微循环障碍相关的9个关键靶点。GO和KEGG通路富集分析发现,丹参治疗微循环障碍可能与氧化还原、钙离子稳态等生物过程有关,能够调节血管内皮生长因子信号通路、神经突触信号传导、催产素信号通路、醛固酮-调节钠重吸收等信号通路。结论丹参治疗微循环障碍体现了多成分、多靶点、多途径的作用特点,为进一步开展丹参治疗微循环障碍作用机制研究提供了新的思路和方法。  相似文献   
44.
冯宇飞  常书源  秦国昭  井中旭  王艳宏 《中草药》2020,51(23):5934-5942
目的 优化线粒体靶向金丝桃苷脂质体(DLD/Hyp-Lip)制备的最佳处方,并研究研究其在胎牛血清中的稳定性及体外释放行为,考察其线粒体靶向性。方法 采用薄膜分散法制备DLD/Hyp-Lip,以包封率和载药量为考察指标进行单因素实验,考察磷脂总量与金丝桃苷(hyperoside,Hyp)用量比、二硬脂酰磷脂酰乙醇胺-聚乙二醇(DSPE-PEG)与DLD用量比等条件对DLD/Hyp-Lip的影响,结合星点设计-效应面法优化DLD/Hyp-Lip处方。使用透射电子显微镜和粒径仪观察测定脂质体粒子外观、平均粒径和Zeta电位,采用血清稳定性实验和体外释药、线粒体靶向性对该载药系统进行评价。结果 DLD/Hyp-Lip最佳处方为磷脂总量和金丝桃苷用量比为12.50:1,磷脂总量与胆固醇用量比为6.00:1,DSPE-PEG与DLD用量比为3:5;测得金丝桃苷包封率为(95.57±0.56)%,载药量为(8.55±0.57)%。所制备的DLD/Hyp-Lip外观良好,平均粒径为(124.9±3.4)nm,Zeta电位为(-6.2±1.9)mV;在胎牛血清中性状稳定,在体外释放介质中24 h累积释放量达到40%。线粒体靶向实验表明DLD/Hyp-Lip可以促进药物聚集在线粒体部位。结论 采用此方法能够精准有效的优化DLD/Hyp-Lip的制备工艺,该方法操作简单方便,可以用于DLD/Hyp-Lip制备与处方的优化,制备的DLD/Hyp-Lip包封率高,粒径小,分布均匀,且具有良好的缓释作用,为DLD/Hyp-Lip的进一步体内研究奠定了基础。载金丝桃苷的DLD/Hyp-Lip具有良好的肝癌细胞线粒体靶向性,是一种潜在高效的肝癌细胞线粒体靶向给药系统。  相似文献   
45.
BackgroundAt a community cancer center, during weekly quality improvement huddles, the radiation therapy team expressed stress and frustration with the pretreatment pathway for patients requiring palliative radiotherapy. As the department was meeting provincial targets with respect to wait times, it was unknown why the consensus around the department reflected discomfort and stress.MethodsFour radiation therapists formed a quality improvement project team, intent on utilizing a data-driven improvement cycle to investigate and address opportunities to improve the discomfort around this pretreatment pathway. After defining the process and identifying the customers (the health care providers operating in this pathway), the team conducted interviews with each person, transcribing answers verbatim, and grouping results by discipline. Utilizing the interview themes, each discipline identified one or two priorities to measure, as well as metrics to capture the magnitude and prevalence of these priorities.ResultsEach discipline's priorities were measured and analyzed. The identified issues brought forward at the weekly quality improvement huddles were not as prevalent as expected. Minor changes were implemented for priority issues.ConclusionThe team focused on the four principles of quality improvement: the patient, team, process, and data to address the expressed discomfort around this specific radiation therapy pathway. The results dispelled some of the myths among teams and provided solutions to areas where minor improvements were required. Utilizing the data, an evidence-informed timeline was validated, encouraging task deadlines to be more evenly distributed across the pathway. Plans to monitor this pathway are being established. The team was successful in contributing to a growing culture of continuous improvement at this community cancer center.  相似文献   
46.
Brachytherapy (BT) delivers integrated boost doses to the central tumor while sparing the surrounding organs at risk (OARs) efficiently. It’s a mandatory treatment component for locally advanced cervical cancer (LACC) because it results in excellent overall survival and local control compared with other dose boosting modalities. Currently, BT is undergoing a transition from 2-dimensional (2D) to 3-dimensional (3D) treatment planning. Imaging-guided BT (IGBT) employing computed tomography (CT) or magnetic resonance imaging (MRI) can provide exact individual delineation of target and OARs meanwhile prescribe the dose to the target volume instead of “point A” for X-ray-based BT. There are three main techniques for BT: intracavitary (IC), interstitial (IS), and intracavitary/interstitial (IC/IS) combination. The applicator choice depends on the specific tumor extension. The real-time transabdominal ultrasound (US)-guided applicator placement technique is strongly recommended to ensure ideal applicator positioning. MRI is the ideal standard imaging for BT owing to its superior soft tissue visualization than CT. However, CT-based BT is more often performed because of the availability. In developing countries, US-based BT can be adopted. For treatment planning, the applicator reconstruction is easier on CT than on MRI, because the applicator image is more clearly visible. Individual treatment planning should be performed for every single applicator insertion to ensure dose accuracy. In this review article, we explain the main clinical process and common techniques, including the applicator choice and placement, imaging techniques, target delineation, and treatment planning; asthose will help to improve the efficiency of 3D BT.  相似文献   
47.
Triple-negative breast cancer (TNBC) is defined as a type of breast cancer with lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor 2 protein. In comparison to other types of breast cancer, TNBC characterizes for its aggressive behavior, more prone to early recurrence and a disease with poor response to molecular target therapy. Although TNBC is identified in only 25%-30% of American breast cancer cases annually, these tumors continue to be a therapeutic challenge for clinicians for several reasons: Tumor heterogeneity, limited and toxic systemic therapy options, and often resistance to current standard therapy, characterized by progressive disease on treatment, residual tumor after cytotoxic chemotherapy, and early recurrence after complete surgical excision. Cell-surface targeted therapies have been successful for breast cancer in general, however there are currently no approved cell-surface targeted therapies specifically indicated for TNBC. Recently, several cell-surface targets have been identified as candidates for treatment of TNBC and associated targeted therapies are in development. The purpose of this work is to review the current clinical challenges posed by TNBC, the therapeutic approaches currently in use, and provide an overview of developing cell surface targeting approaches to improve outcomes for treatment resistant TNBC.  相似文献   
48.
Forgiveness has been found one substantial element in the recovery for women survivors from intimate partner violence following the termination of the abusive relationship. To further investigate the details of forgiveness in this specific context, the present study explored the process of forgiveness using grounded theory. In-depth and semi-structured interviews were conducted with 25 Chinese women survivors of IPV. The findings suggest that forgiveness is a strength-based process including empowerment, transformation, and integration phases. In the empowerment phase, survivors obtain strength at the intrapersonal, behavioural, and interpersonal levels. In the transformation phase, survivors complete cognitive transformation for their IPV experiences and emotional transformation towards former partners. In the integration phase, survivors—now freed from the past—reflect upon and apply the changes they have undergone. Two trajectories in the process were found. One trajectory is going through stages sequentially and the other trajectory is experiencing back and forth between empowerment and transformation stages before moving into the integration stage. The study's findings broaden our knowledge of the strength-based forgiveness process that women survivors of IPV undergo during recovery. Practitioners and policymakers could develop programmes and policies that support forgiveness by holistically facilitating their recovery and empowerment like assistance in dealing with life difficulties and promoting their reconnection with social networks. To improve the transferability and validity of the findings, the forgiveness of survivors of IPV could be explored in a diverse sample (e.g., survivors with low educational background or live in the rural area).  相似文献   
49.
BackgroundAcetabular fractures in the elderly frequently involve segmental quadrilateral plate injury, yet no consensus exists on how to best control the femoral head medial displacement. Quadrilateral surface plates (QSP) were developed to help buttress these challenging fractures. The study aims to 1) Determine the prevalence of segmental quadrilateral plate fractures (SQPF) in elderly patients; and 2) Assess if utilization of a QSP is associated with improved acetabulum fracture reduction and outcome.MethodsThis was a retrospective study conducted at a level-1 trauma centre. . All patients over 60-years that sustained an acetabular fracture between 2007 and 2019 were reviewed. Pre-operative pelvic radiographs and CT imaging were reviewed for 96 patients, to assess for SQPF. From the 96 patients reviewed, over one third of patients (n = 40, 41.6%) sustained a SQPF. Patients that had an acute-THA (n = 7) were excluded as were patients that underwent an ORIF but did not have a QSP or an anterior column buttress plate (n = 3). The remaining 30 formed the study’s cohort. We assessed the ability to achieve and maintain reduction in this elderly population, and compared outcomes using traditional anterior column buttress plates (ilioingual or intra-pelvic approach) versus an intra-pelvic pre-contoured buttress suprapectineal plate (QSP). Outcome measures included: fracture reduction using the Matta classification (desirable: anatomical/imperfect and poor), re-operations, conversion to THA and Oxford Hip Score (OHS) (for the preserved hips).ResultsTen patients had an ORIF with utilization of a QSP (QSP-group), and 20 had an ORIF but did not have the QSP (non-QSP-group). There was no difference in patient demographics between groups. Fracture patterns were also similar (p = 0.6). Postoperative fracture reduction was desirable (anatomical/imperfect) in 17 patients and poor in 13. Improved ability to achieve a desirable reduction was seen in the QSP-group (p = 0.02). Conversion to THA was significantly lower in patients that had a desirable fracture reduction (appropriate: 3/17; poor: 7/13). No patients in the QSP-group have required a THA to-date, compared to 10/20 patients in the non-QSP-group (p = 0.01). The mean time to THA was 1.6 ± 2.1 year. There was no difference in OHS between the two groups (34.4 ± 10.3).ConclusionElderly acetabulum fractures have a high incidence (approaching 40%) of segmental QPF. Desirable (anatomical/imperfect) fracture reduction was associated with improved outcome. The use of a QSP was associated with improved ability to achieve an appropriate reduction. A QSP should be considered as they are both reliable and reproducible with a significantly improved fracture reduction and lower conversion to THA.  相似文献   
50.
By means of the ultrasonic surface impact (amplitude of 30 μm, strike number of 48,000 times/mm2), nanograins have been achieved in the surfaces of both Ti6Al4V(TC4) and Ti3Zr2Sn3Mo25Nb(TLM) titanium alloys, mainly because of the dislocation motion. Many mechanical properties are improved, such as hardness, residual stress, and roughness. The rotating–bending fatigue limits of TC4 and TLM subjected to ultrasonic impact are improved by 13.1% and 23.7%, separately. Because of the bending fatigue behavior, which is sensitive to the surface condition, cracks usually initiate from the surface defects under high stress amplitude. By means of an ultrasonic impact tip with the size of 8 mm, most of the inner cracks present at the zone with a depth range of 100~250 μm in the high life region. The inner crack core to TC4 usually appears as a deformed long and narrow α-phase, while the cracks in TLM specimens prefer to initiate at the triple grain boundary junctions. This zone crosses the grain refined layer and the deformed coarse grain layer. With the gradient change of elastic parameters, the model shows an increase of normal stress at this zone. Combined with the loss of plasticity and toughness, it is easy to understand these fatigue behaviors.  相似文献   
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