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61.
Background:  Acitretin has been shown to be effective for psoriasis treatment. Its mechanism of action is not completely understood, and there are few studies focusing on histological and immunohistochemical differences before and after treatment of psoriasis with acitretin.
Methods:  This is a prospective study of 17 patients with plaque psoriasis treated with acitretin for 4 months with biopsies taken before and after therapy. Histological features and immunohistochemical reactions to cytokeratin (CK) 10, CK16, CK19, Ki67 and CD1a were evaluated and compared.
Results:  There were nine men and eight women with median age of 47 years. Epidermal thickness, CK16 positivity, Ki67 and CD1a-positive cell index reduced after treatment (p < 0.01). Suprapapillary plate thickness stayed the same (p > 0.05) although the epidermal/suprapapillary thickness ratio was significantly higher before treatment (p < 0.01). CK10 positivity was lower and a thicker basal cell layer was seen in the epidermis before treatment (p < 0.01). CK19 was negative in all cases.
Conclusions:  Acitretin therapy improved histological and immunohistochemical features typical of psoriasis. In psoriasis, suprapapillary plates are not thin, but the epidermal/suprapapillary thickness ratio is increased. Basal cell layer is expanded in psoriasis. Langerhans' cells were less frequent after treatment, and that finding has to be investigated further to determine its role in acitretin mechanism of action.  相似文献   
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Primary or secondary tricuspid regurgitation (TR) represents an important health care burden and challenge which has often been neglected or undertreated in the past. The expansion and reinforcement of the indications for tricuspid valve (TV) intervention in the 2017 editions of the guidelines as well as the introduction of transcatheter tricuspid valve intervention (TTVI) has considerably increased the attention of the community on the TV and the volume of TV interventions in the past years. Depending on the anatomic target, TTVI can be categorized as the following: 1) direct or indirect tricuspid restrictive annuloplasty; 2) direct (edge-to-edge repair) or indirect (coaptation device) restoration of leaflet coaptation; 3) heterotopic tricuspid valve implantation; and 4) transcatheter tricuspid valve replacement. Multimodality imaging has crucial role for the following: 1) patient selection for TTVI and procedure planning; 2) guiding and monitoring the procedure; and 3) assessing and following over time the results of the procedure. The key points for pre-procedural imaging are: 1) accurate quantitation of TR severity; 2) proper identification of the mechanism(s) responsible for the TR; and 3) quantitation of RV dysfunction and pulmonary arterial hypertension. This imaging work-up is essential to select the right type of intervention for the right patient and TV. Transesophageal echocardiography and fluoroscopy imaging is also key for guiding the TTVI procedures and fusion between these 2 modalities may further enhance the quality of procedure guiding.  相似文献   
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We investigated the effects of LASSBio-998 (L-998), a compound designed to be a p38 MAPK (mitogen-activated protein kinase) inhibitor, on lipopolysaccharide (LPS)-induced acute lung inflammation in vivo. BALB/c mice were challenged with aerosolized LPS inhalation (0.5 mg/ml) 4 h after oral administration of L-998. Three hours after LPS inhalation, bronchoalveolar lavage fluid was obtained to measure the levels of the proinflammatory cytokines TNF-α (tumor necrosis factor-α) and IL-1 (interleukin-1) and the chemokines MCP-1 (monocyte chemoattractant protein-1) and KC (keratinocyte chemoattractant). In addition, neutrophil infiltration and p38 MAPK phosphorylation was measured. L-998 inhibited LPS-induced production of TNF-α and IL-1β and did not alter KC and MCP-1 levels. Furthermore, L-998 also significantly decreased neutrophil accumulation in lung tissues. As expected, L-998 diminished p38 MAPK phosphorylation and reduced acute lung inflammation. Inhibition of p38 MAPK phosphorylation by L-998 was also demonstrated in LPS-challenged murine C57BL/6 peritoneal macrophages in vitro, with concentration-dependent effects. L-998 suppressed LPS-induced lung inflammation, most likely by inhibition of the cytokine-p38 MAPK pathway, and we postulate that L-998 could be a clinically relevant anti-inflammatory drug candidate.  相似文献   
64.
Introduction: To examine hospitalizations in a cohort of 224 patients who presented with non‐fatal heroin overdose to an ED. Methods: A record linkage study, using the morbidity, mental health and mortality databases in the Data Linkage Unit of the Department of Health, Western Australia. The main outcome measures were hospital separations 5 years before and after entry into the cohort. Results: Before entry into the cohort, 199 (89%) patients had an admission to mental health services. These 199 had a combined total of 1367 separations, most commonly for a mental health condition, injury or poisoning. Women had more than twice the relative risk (RR) of men for all separations (RR 2.35, 95% confidence interval [CI] 1.96–2.82, P < 0.001) and for injury and poisoning separations (RR 2.04, 95% CI 1.56–2.66, P < 0.001). The highest concentrations of separations occurred within 1 year before and 1 year after entry into the cohort. There were 12 (5.4%, 95% CI 2.9–9.4%) deaths, most commonly from overdose. Conclusion: Non‐fatal heroin overdose ED presentations are associated with a cluster of hospitalizations around that episode, likely to be related to heroin availability. Presentation to hospital by heroin users represents an opportunity to counsel less risky behaviour.  相似文献   
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目的:分析肾移植术后常见并发症肾功能延迟恢复的诱因,并观察术后血液净化干预所发挥的临床效应。方法:选择1996—12/2006—12在解放军第三军医大学大坪医院野战外科研究所泌尿外科明确诊断为肾移植术后肾功能延迟恢复的患者193例,其中接受尸肾移植192例,活体肾移植1例,均知情同意。根据患者的临床资料,分析术后肾功能延迟恢复的主要原因。除5例因术前安置腹膜透析管继续采用腹膜透析外,其余均选择血液透析治疗,其中35例穿插接受过连续性肾脏替代治疗或血液透析滤过,8例血浆置换2-5次。终止透析的标准为每日尿量〉1500mL,血肌酐〈300μmol/L。分析术后肾功能延迟恢复的原因,观察接受透析治疗后肾功能延迟恢复患者的临床疗效。结果:193例患者全部进入结果分析。①术后肾功能延迟恢复的病因:急性肾小管坏死89例(46.1%),术后早期低血压42例(21.8%),排斥反应37例(19.2%),动静脉吻合口狭窄9例(4-7%),尿路梗阻8例(4.1%),动脉过长扭曲5例(2.6%),环孢素A肾毒性2例(1.0%),髂内动脉粥样硬化斑块阻塞1例(0.5%)。(④术后肾功能转归:移植肾功能恢复正常者145例(75.1%);术后3个月血肌酐135-300μmol/L29例(15.3%);〉300μmol/L15例(7.8%);因超急性排斥反应切除移植肾2例(1%),肺部重症感染死亡2例(1%)。③术后接受血液透析次数:术后接受血液透析189例,透析1—5次移植肾功能恢复正常20例(13.8%);6-10次41例(28.3%);11-20次82例(56.6%);21-25次2例(1.4%);〉25次44例,仅1例恢复正常(0.7%),其余43例患者带肾存活。结论:急性肾小管坏死、术后早期低血压和排斥反应是引起肾移植术后肾功能延迟恢复的主要原因。在肾功能延迟恢复患者确定以血液净化为主的方案后,绝大多数移植肾功能可以恢复。  相似文献   
69.
薄层扫描法测定熊胆引流物中胆汁酸含量   总被引:4,自引:0,他引:4  
熊胆向以贵重药材闻名,被称之为稀有药品,为开发熊胆资源,解决熊胆奇缺问题,我校解剖教研室已成功地完成了人工引流熊胆汁技术,可随时进行人工引流获取熊胆汁。为了确定胆汁的质量指标,了解其主要成分,我们进行了引流胆汁与天然熊胆的分析。文献报道,熊胆中主要含熊去氧胆酸(ursodesoxycholic acid,UDCA)、鹅去氧胆酸(cheno desoxycholic acid,CDCA)、胆酸(cholic acid,CA)、去氧胆酸(deoxycholic,acid DCA)等。  相似文献   
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