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31.
目的探讨胃肠道钙化性纤维性肿瘤(CFT)的临床病理特点及诊断和鉴别诊断要点。方法回顾性分析2016年1月至2019年6月首都医科大学附属北京友谊医院收治的6例胃肠道CFT患者的病例资料,对其进行病理形态学观察和免疫组织化学染色分析,并进行文献复习。结果6例胃肠道CFT患者中,男性2例,女性4例;年龄20~43岁,平均年龄35岁;5例发生于胃,1例发生于回盲部;胃肠镜表现为黏膜下隆起性病变,黏膜面光滑;组织学表现为大量玻璃样变性的胶原纤维,其内可见稀疏分布的梭形细胞,散在及灶状淋巴细胞、浆细胞浸润,伴营养不良性钙化和砂粒体形成;免疫组化:肿瘤细胞表达Vimentin,不表达CD117、DOG-1、CD34、Actin、Desmin、S-100,ALK、Ig G、Ig G4,Ki-67指数为0~5%;6例患者均采用手术或内镜下肿物切除治疗,随访6~31个月,均未出现复发及转移。结论胃肠道CFT是一种罕见的良性纤维性肿瘤,容易误诊为消化道其他间叶来源性肿瘤,应结合临床资料、组织形态及免疫表型做出综合诊断。手术切除可治愈,预后良好。  相似文献   
32.
目的:应用经食管实时三维超声心动图(RT-3D-TEE)技术,探讨房性心律失常对二尖瓣结构和功能的影响.方法:选取2018年6月~2019年6月本院收治的房性心律失常拟行射频消融的患者49例纳入观察组,另外选取21例正常窦性心律者作为对照组,所有患者均行经胸超声心电图(TTE)和经食管实时三维超声心动图(RT-3D-TEE)检查,将两组患者的瓣环投影面积(A2D)、瓣环周长(C3D)、瓣环高度(H)、瓣环前后径(DAP)、瓣环前外侧至后内侧直径(DAIPm)、左室射血分数(LVEF)、左心房前后径(Lad)等参数进行比较,并分别计算对合面积和对合指数,之后采取二项Logistic回归分析或逐步线性回归对各参数及临床因素与对合指数的相关性进行分析.结果:两组患者在LVEF和对合面积方面的比较无明显差异(P>0.05),在A2D、C3D、H、DA、PDAIPm、Lad方面的比较,房性心律失常组患者明显高于正常窦性心律组患者(P<0.05),且观察组患者的对合指数明显降低(P<0.05).将49例观察组患者以不同心律失常类型分为持续性房颤、阵发性房颤、房扑、混合型房性心律失常4个亚组,采用单因素方差分析,发现在LVEF、C3D、Lad、对合指数方面的比较,各亚组间无明显差异(P>0.05).采用二项Logistic回归分析发现,女性是导致对合指数低的危险因素,另外对合指数较低、房性心律失常是导致二尖瓣返流的重要因素.结论:房性心律失常对患者二尖瓣的A2D、C3D、H、DA、PDAIPm、Lad等都会造成较大影响,从而降低对合指数,影响二尖瓣的正常功能,导致二尖瓣返流的发生.  相似文献   
33.
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   
34.
Major depressive disorder (MDD) has been the subject of many neuroimaging case–control classification studies. Although some studies report accuracies ≥80%, most have investigated relatively small samples of clinically‐ascertained, currently symptomatic cases, and did not attempt replication in larger samples. We here first aimed to replicate previously reported classification accuracies in a small, well‐phenotyped community‐based group of current MDD cases with clinical interview‐based diagnoses (from STratifying Resilience and Depression Longitudinally cohort, ‘STRADL’). We performed a set of exploratory predictive classification analyses with measures related to brain morphometry and white matter integrity. We applied three classifier types—SVM, penalised logistic regression or decision tree—either with or without optimisation, and with or without feature selection. We then determined whether similar accuracies could be replicated in a larger independent population‐based sample with self‐reported current depression (UK Biobank cohort). Additional analyses extended to lifetime MDD diagnoses—remitted MDD in STRADL, and lifetime‐experienced MDD in UK Biobank. The highest cross‐validation accuracy (75%) was achieved in the initial current MDD sample with a decision tree classifier and cortical surface area features. The most frequently selected decision tree split variables included surface areas of bilateral caudal anterior cingulate, left lingual gyrus, left superior frontal, right precentral and paracentral regions. High accuracy was not achieved in the larger samples with self‐reported current depression (53.73%), with remitted MDD (57.48%), or with lifetime‐experienced MDD (52.68–60.29%). Our results indicate that high predictive classification accuracies may not immediately translate to larger samples with broader criteria for depression, and may not be robust across different classification approaches.  相似文献   
35.
Thus far, four studies have used magnetic resonance imaging (MRI) to test for differences in brain structure between paedophilic (i.e. sexually attracted to pre-pubescent children) and teleiophilic (i.e. sexually attracted to adults) men, revealing divergent results. To re-examine this issue, we acquired high resolution structural T1-weighted and diffusion MRI scans of the brain in 24 paedophilic and 32 teleiophilic men. We performed voxel-based morphometry (VBM) of the T1-weighted images and tract-based spatial statistics (TBSS) of the diffusion tensor imaging data to search for grey and white matter differences between groups. In contrast to previous studies, less than half of the individuals in our paedophilic group had a record of sexual offences against children, as subjects were partially recruited from two outpatient facilities of a child sexual abuse prevention project for self-acknowledged paedophiles. After adjustment for multiple comparisons and controlling for important confounding factors, we did not find any significant grey or white matter differences between the paedophilic and teleiophilic subjects. Together with the inconsistencies in the literature, these results argue against consistent structural differences at the macroanatomical scale between paedophiles and teleiophiles.  相似文献   
36.
Conclusions: No significant subepithelial healing differences were found between Gelfoam and polyurethane foam (PUF). However, levels of hyperplasia of the mucosal lining and inflammation were lower with PUF packing. PUF packing is not feasible as a middle ear packing material for abraded mucosa. Further studies are required before clinical application. Objective: To date, there have been few reports on the antiadhesive effect of PUF as a middle ear packing. The purpose of this study was to investigate the antiadhesive effect of PUF soaked with saline in an animal model of mucosal trauma. Methods: Bioresorbable PUF soaked with saline was placed over abraded mucosa in the experimental group (n = 7), and compressed Gelfoam soaked with saline was placed in the control group (n = 7). After measurement of auditory brainstem responses (ABRs), the animals were sacrificed 3 weeks after packing placement for histological observation. Results: The ABR results at postoperative week 3 showed no statistically significant difference between the preoperative and post-packing values. An adhesion pattern with subepithelial thickening was observed in the control group. Adhesion was not observed in the experimental group; however, subepithelial fibrous thickening was noted.  相似文献   
37.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.

Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.

Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).

Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.

Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases.  相似文献   
38.
目的调查我国三级综合医院护理质量管理组织架构。方法对全国85所医院相关护理人员进行问卷调查,并采用半结构式访谈法对其中11所医院护理质量管理专家进行访谈。结果90.6%的医院护理质量管理采用三级管理;85所医院均设有护理质量管理委员会,其中9.4%的委员会中缺少护士长参与,54.1%的护理质量管理委员会由护理队伍独立组成;访谈资料归纳出3个主题为;护理质量管理组织架构和运行方式较成熟,但仍需改进;希望多部门共同参与护理质量管理以及对目前护理质量管理组织架构的建议。结论建议优化护理质量管理三级模式和运行方式,建立多部门合作机制.鼓励护士长参与质量控制,并根据医院自身实际调整护理质量管理架构,以促进护理质量持续改进。  相似文献   
39.
目的 采用16S rRNA技术研究葛根芩连汤对菌群失调性腹泻大鼠肠道菌群结构的影响。方法 将60只健康SD大鼠随机分为6组,分别为正常组、模型组、葛根芩连汤高、中、低剂量组,丽珠肠乐组,每组10只。除正常组外,每日按头孢拉定178.6 mg·kg-1,硫酸庆大霉素31.25 mg·kg-1混合抗生素进行灌胃造模,造模成功后,葛根芩连汤高、中、低剂量组灌胃葛根芩连汤(7.02,3.51,1.755 g·kg-1),丽珠肠乐组按0.125 g·kg-1灌胃,正常组与模型组给予无菌蒸馏水灌胃,体积分数均为10 mL·kg-1,连续给药7 d,将大鼠麻醉后取大鼠结肠内容物,提取粪便DNA后进行16S rRNA高通量测序并分析其结果。结果 葛根芩连汤明显调节菌群失调性腹泻模型大鼠的物种数量及Alpha与Beta多样性,提高菌群生物丰富度指数与多样性指数,正向调节菌群失调性腹泻模型大鼠的3种差异菌门(厚壁菌门、变形菌门、拟杆菌门)与14种差异菌属(拟杆菌属、狄氏副拟杆菌属、布劳特氏菌属等)。结论 葛根芩连汤对菌群失调性腹泻模型大鼠肠道菌群有调节作用,揭示了肠道菌群与菌群失调性腹泻之间的生理病理机制。  相似文献   
40.
Inflammatory processes are implicated in the aetiology of Major Depressive Disorder (MDD); however, the relationship between peripheral inflammation, brain structure and depression remains unclear, partly due to complexities around the use of acute/phasic inflammatory biomarkers.Here, we report the first large-scale study of both serological and methylomic signatures of CRP (considered to represent acute and chronic measures of inflammation respectively) and their associations with depression status/symptoms, and structural neuroimaging phenotypes (T1 and diffusion MRI) in a large community-based sample (Generation Scotland; NMDD cases = 271, Ncontrols = 609).Serum CRP was associated with overall MDD severity, and specifically with current somatic symptoms- general interest (β = 0.145, PFDR = 6 × 10−4) and energy levels (β = 0.101, PFDR = 0.027), along with reduced entorhinal cortex thickness (β = −0.095, PFDR = 0.037). DNAm CRP was significantly associated with reduced global grey matter/cortical volume and widespread reductions in integrity of 16/24 white matter tracts (with greatest regional effects in the external and internal capsules, βFA= −0.12 to −0.14). In general, the methylation-based measures showed stronger associations with imaging metrics than serum-based CRP measures (βaverage = −0.15 versus βaverage = 0.01 respectively).These findings provide evidence for central effects of peripheral inflammation from both serological and epigenetic markers of inflammation, including in brain regions previously implicated in depression. This suggests that these imaging measures may be involved in the relationship between peripheral inflammation and somatic/depressive symptoms. Notably, greater effects on brain morphology were seen for methylation-based rather than serum-based measures of inflammation, indicating the importance of such measures for future studies.  相似文献   
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