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1.
ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.  相似文献   
2.
Podophyllotoxin (PPT) exhibited significant activity against P-glycoprotein mediated multidrug resistant (MDR) tumor cell lines; however, due to its poor solubility and high toxicity, PPT cannot be dosed systemically, preventing its clinical use for MDR cancer. We developed a nanoparticle dosage form of PPT by covalently conjugating PPT and polyethylene glycol (PEG) with acetylated carboxymethyl cellulose (CMC-Ac) using one-pot esterification chemistry. The polymer conjugates self-assembled into nanoparticles (NPs) of variable sizes (20–120 nm) depending on the PPT-to-PEG molar ratio (2–20). The conjugate with a low PPT/PEG molar ratio of 2 yielded NPs with a mean diameter of 20 nm and released PPT at ∼5%/day in serum, while conjugates with increased PPT/PEG ratios (5 and 20) produced bigger particles (30 nm and 120 nm respectively) that displayed slower drug release (∼2.5%/day and ∼1%/day respectively). The 20 nm particles exhibited 2- to 5-fold enhanced cell killing potency and 5- to 20-fold increased tumor delivery compared to the larger NPs. The biodistribution of the 20 nm PPT-NPs was highly selective to the tumor with 8-fold higher accumulation than all other examined tissues, while the larger PPT-NPs (30 and 120 nm) exhibited increased liver uptake. Within the tumor, >90% of the 20 nm PPT-NPs penetrated to the hypovascular core, while the larger particles were largely restricted in the hypervascular periphery. The 20 nm PPT-NPs displayed significantly improved efficacy against MDR tumors in mice compared to the larger PPT-NPs, native PPT and the standard taxane chemotherapies, with minimal toxicity.  相似文献   
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Malaria, one of the most striking, re-emerging infectious diseases caused by the genus Plasmodium, places a huge burden on global healthcare systems. A major challenge in the control and eradication of malaria is the continuous emergence of increasingly widespread drug-resistant malaria, creating an urgent need to develop novel antimalarial agents. Chalcone derivatives are ubiquitous in nature and have become indispensable units in medicinal chemistry applications due to their diverse biological profiles. Many chalcone derivatives demonstrate potential in vitro and in vivo antimalarial activity, so chalcone could be a useful template for the development of novel antimalarial agents. This review covers the recent development of chalcone hybrids as antimalarial agents. The critical aspects of the design and structure–activity relationship of these compounds are also discussed.  相似文献   
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目的总结多发性硬化(MS)患者的临床特点(精神情感障碍)以及脑脊液、诱发电位、影像学改变进行分析。方法回顾分析65例MS患者的有关临床和实验室资料。结果65例中,男17例,女48例;年龄16~68岁,平均(36.5±14.1)岁,男女比为1∶2.8。MS首发及常见症状为感觉异常、肢体无力、视力减退及括约肌功能障碍,病变部位以脊髓受累最多见,部分患者存在精神情感障碍。结论出现感觉异常有助于MS早期诊断,诱发电位及MRI有助于发现亚临床病变;括约肌功能异常多见,可能与脊髓受累较多有关;MS患者的精神情感应受人们关注。  相似文献   
6.
目的了解基层公共卫生人员心身健康状况及影响因素,为提高其健康水平和工作质量提供科学依据。方法应用中国心身健康量表,采用分层整群抽样的方式,抽取胶州、嘉祥、兖州和邹城疾病预防控制中心及下属防保站的公共卫生人员584名进行问卷调查。结果基层公共卫生人员心身障碍发生率为39.43%,其中最高为骨骼系统14.17%,其次为神经系统12.73%;呼吸系统、心血管系统、焦虑、抑郁、精神病性5项因子评分小于全国常模;运用二分类Logistic逐步回归分析显示,从事本行业年限的增加是引起眼和耳疾病的危险性因素(OR=1.067),职务的增高是导致心血管系统(OR=1.878)、消化系统(OR=1.675)、精神病性(OR=1.841)疾患的危险性因素;核心家庭(OR=0.136)、扩展家庭(OR=0.143)是降低抑郁发生的保护性因素。结论相关部门应采取综合措施,从工作和家庭环境等方面入手,提高基层公共卫生人员的心身健康水平。  相似文献   
7.
目的 基于倾向性评分逆处理概率加权(IPTW)法评估EB病毒(EBV)在结外NK/T细胞淋巴瘤患者中的预后价值。方法 收集2012年10月—2021年4月淮海淋巴瘤协作组中8家医疗机构初诊为结外NK/T细胞淋巴瘤且具有全血EBV-DNA数据的468例患者的临床资料。采用IPTW法分析EBV载量对结外NK/T细胞淋巴瘤患者生存期的影响;采用Cox比例风险模型进行多因素分析;绘制Kaplan-Meier曲线,组间比较采用Log rank χ2检验。结果 468例结外NK/T细胞淋巴瘤患者中,EBV-DNA阳性266例,EBV-DNA阴性202例。EBV-DNA阳性组和阴性组患者的5年OS分别为62.5%和89.2%,两组比较,经Log rank χ2检验,差异有统计学意义(χ2=42.900,P=0.000)。IPTW前,两组的美国东部肿瘤协作组(ECOG)活动状态(PS)评分(ECOG PS评分)、原发部位、CA分期、Ann Arbor分期、白蛋白、乳酸脱氢酶、治疗方案比较,差异均有统计学意义(P<0.05)。IPT...  相似文献   
8.
目的探讨极早产儿发生支气管肺发育不良(BPD)的影响因素。 方法选择2020年1月1日至12月31日,于青岛大学附属医院、青岛市市立医院、济宁市第一人民医院及枣庄市妇幼保健院出生并接受治疗的208例极早产儿为研究对象。根据是否发生BPD,将其分为BPD组(n=153)和非BPD组(n=55);再根据BPD严重程度分度,将BPD组极早产儿分为Ⅰ度BPD亚组(n=31)、Ⅱ度BPD亚组(n=17)及Ⅲ度BPD亚组(n=7)。采用回顾性分析法,统计学比较BPD组与非BPD组,以及3个BPD亚组极早产儿出生与治疗情况、生后14 d内液体摄入量等。采用多因素非条件logistic回归分析,探讨极早产儿发生BPD及BPD极早产儿发生Ⅲ度BPD的影响因素。本研究经青岛大学附属医院医学伦理委员会批准(审批文号:QYFYWZLL26841),并且与所有患儿监护人签署临床研究知情同意书。 结果①BPD组极早产儿出生胎龄、体重、头围及身长,以及生后1、5、10 min Apgar评分,均小于、轻于、短于、低于非BPD组;而孕母产前激素使用率,极早产儿出生窒息率、肺表面活性剂(PS)使用率及早发型败血症(EOS)发生率,以及有创及无创机械通气时间,均高于、长于非BPD组,并且差异均有统计学意义(P<0.05)。②BPD组极早产儿生后第2、4、5、7、11、12天的总液体摄入量,以及生后第6、8~14天肠外液体静脉输注量,均多于非BPD组;生后第1~14天肠内液体摄入量,则均少于非BPD组,并且上述差异均有统计学意义(P<0.05)。③多因素非条件logistic回归分析:极早产儿生后1 min Apgar评分低(OR=1.866,95%CI:1.063~3.274,P=0.030),有创机械通气时间长(OR=1.834,95%CI:1.158~2.905,P=0.010),无创机械通气时间长(OR=1.163,95%CI:1.067~1.267,P=0.001),发生EOS(OR=0.071,95%CI:0.011~0.465,P=0.006)是极早产儿发生BPD的独立危险因素;生后第3、4、5天肠内液体摄入量多(OR=0.671、0.708、0.746,95%CI:0.483~0.932、0.511~0.846、0.583~0.955,P=0.017、0.004、0.020),是极早产儿发生BPD的独立保护因素。④3个BPD亚组极早产儿出生胎龄、孕母产前激素使用率、出生窒息率、EOS发生率及有创机械通气时间,生后第1、2、4、5、6天总液体摄入量及肠外液体静脉输注量,以及生后第1天肠内液体摄入量比较,差异均有统计学意义(均为P<0.05)。但是,这16项因素均不是BPD极早产儿发生Ⅲ度BPD的独立影响因素。 结论极早产儿发生BPD是多种因素共同作用的结果,减少出生窒息及EOS发生率,优化呼吸支持策略,增加生后第3~5天肠内液体摄入量,有望降低极早产儿BPD发生率。  相似文献   
9.
BackgroundThe Child and Adult Care Food Program (CACFP) nutrition standards may present food purchasing, preparation, and feeding challenges for caregivers of young children.ObjectiveTo elucidate perceived barriers and facilitators faced by in-home childcare providers to following the CACFP food and beverage nutrition standards.DesignVirtual, semistructured individual interviews elicited perceptions from a cross section of low-income, in-home childcare providers in Michigan.Participants/settingsTwenty childcare providers of various races, ethnicity, urban and rural residence, and licensure status.AnalysisThematic coding analysis with NVivo (ver12.0) to organize and interpret data.ResultsFour primary barriers to adhering to the CACFP nutrition standards emerged including (1) noncompliant food preferences of children and providers; (2) higher cost and lower availability of CACFP-approved items; (3) celebrations and food rewards; (4) excessive time and effort needed to prepare foods and beverages, especially with dietary restrictions for some children. Ten perceived facilitators included (1) using nutrition education available through community organizations; (2) finding convenient and easy ways to prepare foods and beverages; (3) using CACFP and Special Supplemental Nutrition Program for Women, Infants, and Children guidelines and funding; (4) increasing variety of foods and beverages by using a menu or recalling items recently served; (5) modeling eating healthful foods and encouraging sampling of new foods and beverages; (6) mixing preferred foods/beverages with less preferred; (7) using nutrition information available from social media and from peers; (8) allowing children to choose foods and beverages; (9) serving the same eligible food and beverages to all children; and (10) provider concern about impact of foods and beverages on children’s health and behavior.ConclusionsResults from this study can inform nutrition education from community organizations that occurs in tandem with CACFP sponsor organizations. In addition, they can be utilized to address state-level licensure regulations and quality improvement rating systems that include nutrition standards childcare providers are encouraged or required to follow.  相似文献   
10.
当归四逆汤(Danggui Sini Decoction,DSD)是治疗血虚寒厥证的代表方剂,具有温经散寒、养血通脉等功效,临床多用于治疗冠心病、心绞痛、雷诺氏征、糖尿病周围神经病变、痛经、膝骨关节炎等疾病。在对DSD化学成分、药理作用和临床应用研究进展进行综述的基础上,依据中药质量标志物(quality marker,Q-Marker)“五原则”对其Q-Marker进行预测分析。结果提示阿魏酸、藁本内酯、肉桂酸、桂皮醛、芍药苷、芍药内酯苷、甘草苷、甘草酸和细辛脂素可作为DSD的Q-Marker,为DSD及其相关制剂的质量控制等后续研究提供参考。  相似文献   
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