经皮肺动脉瓣置换动物实验研究

目的 探讨新型带瓣膜雕刻支架经皮植入置换肺动脉瓣的可行性和疗效.方法 自行设计圆柱状网状支架,用医用316 L不锈钢激光雕刻而成.将新鲜的猪心包经脱细胞处理后置0.6%戊二醛浸泡36 h,生理盐水洗净,裁剪成人工瓣膜,缝合在不锈钢支架上,制成带瓣膜肺动脉支架.手术前将带瓣膜支架压缩至定制的相应大小的球囊导管上.选择健康犬8只,体重(15.5 ± 3.1)kg,穿刺右股静脉,将带瓣膜支架经导管植入至肺动脉瓣处,置换自身肺动脉瓣膜.手术后通过DSA和超声等方法即刻观察实验效果.结果 1只犬死于术中麻醉意外,7只犬经皮瓣膜置换术均获得成功,术后即时影像和超声检查结果表明人工肺动脉瓣膜功能正常.结论 自制新型带瓣膜支架经导管植入置换肺动脉瓣方法可行,效果理想.     

犬急性骨水泥肺栓塞的实验研究

目的通过股静脉注入骨水泥建立犬急性肺栓塞模型,探讨一定剂量范围内不同量骨水泥肺栓塞引起的生理病理变化间的差异。方法 18只成年家犬随机分成A、B、C 3组,每组6只,麻醉后行胸部CT平扫,穿刺右股静脉、左股动脉并置入血管鞘,经静脉鞘注入聚甲基丙烯酸甲酯(PMMA)A组0.5 ml,B组1 ml,C组2 ml。于注入PMMA前和注入后即刻、30 min及1 h分别检测血气分析、平均肺动脉压;于注入PMMA前、后5 min行肺动脉造影。术后1h行胸部CT平扫+增强。术后2 h将犬处死,开胸解剖观察大体形态后,沿肺动脉分支方向随机取肺组织3块进行病理学检查。结果 18只实验犬经股静脉注入PMMA操作均成功,经CT及病理证实均成功建立急性骨水泥肺栓塞模型。各组实验犬动脉血氧分压、二氧化碳分压在骨水泥注入前后差异均无统计学意义(P>0.05)。仅C组骨水泥注入后即刻平均肺动脉压为(24.12±1.74)mmHg,注入后30 min为(23.84±1.25)mmHg,注入后1 h为(24.17±1.63)mmHg,均较注射前的(16.47±0.55)mmHg差异有统计学意义(P<0.05)。A组、B组平均肺动脉压在骨水泥注入前后差异均无统计学意义(P>0.05)。各组实验犬术后胸部CT平扫均可见两肺高密度影,下肺多见,C组尤为明显。部分实验犬平扫见条索状阴影及肺不张征象。C组部分实验犬胸部增强CT可见肺动脉小分支内部分充盈缺损。肺动脉造影仅C组部分实验犬出现肺内部分细小血管减少,血管纹理稀疏,未见肺动脉主干及分支的充盈缺损。病理学检查均发现肺动脉分支存在骨水泥栓子,未见继发血栓形成。结论≤2 ml的骨水泥致急性肺栓塞的严重程度与注入骨水泥剂量没有相关性。在心肺功能正常情况下,≤2 ml的急性骨水泥肺栓塞不会引起明显的呼吸功能障碍。     

载有匹伐他汀的纳米涂层支架的研究

目的探讨新型载有他汀药物的纳米涂层支架的有效性及安全性。方法选用生物可吸收性高分子聚合物聚乳酸-羧基乙酸共聚体(PLGA)为原料制作纳米粒子,并用自行研发的阳离子电镀涂层技术将载有荧光标记物异硫氰酸荧光素(FITC)的PLGA纳米粒子均匀涂层于支架表面。先在体外培养人冠状动脉平滑肌细胞及人脐带静脉内皮细胞,比较研究他汀类药物、雷帕霉素和紫杉醇对平滑肌细胞和内皮细胞增殖能力的影响。同时,选择猪作为实验动物行冠状动脉支架植入术,观察载有他汀的纳米涂层支架对内膜增生及内皮再生的影响。结果体外实验发现,在24 h内FITC从纳米粒子内释放出约40%,在30 d后完全释放。FITC纳米粒子56 d以后从涂层支架完全释放。与其他他汀类药物相比,匹伐他汀对平滑肌细胞增殖有明显的抑制作用(P<0.001),并对内皮细胞再生有促进作用(p<0.05)。尽管雷帕霉素和紫杉醇也都能抑制平滑肌细胞的增殖,但匹伐他汀可在最低浓度(0.01μmol/L)即可达到抑制效果(P<0.05)。匹伐他汀纳米粒子涂层支架组与非药物涂层支架组相比内膜增生明显减少(P<0.01)。与雷帕霉素支架组相比,匹伐他汀纳米粒子涂层支架组的内膜增生程度相近(P>0.05),且炎症、纤维沉积及内皮再生延迟作用均明显减少(P值均<0.01)。结论成功开发载有匹伐他汀纳米粒子涂层支架,初步结果显示该支架既可抑制支架内再狭窄,也可减少支架内血栓形成。     

老年重症肺部感染患者血清降钙素原表达水平及对机械通气撤机结局的预测价值

目的观察老年重症肺部感染患者血清降钙素原(PCT)表达水平,探讨其对机械通气撤机结局的预测价值。方法选取重症肺部感染老年患者50例为重症组,轻中重度肺部感染老年患者30例为非重症组,另选取同期体检健康患者30例为对照组。对比3组入院24 h内血清PCT、超敏C反应蛋白(hs-CRP)水平,以及重症组不同病原体感染患者上述指标差异。观察重症组48 h内的撤机结局,分析撤机前血清PCT、hs-CRP和白细胞计数(WBC)水平对撤机结局的预测价值。结果1重症组血清PCT显著高于非重症组和对照组(P0.05)。2重症组细菌性感染30例,病毒性感染13例,支原体感染7例,重症组细菌性感染患者血清PCT和WBC显著高于病毒性感染和支原体感染患者(P0.05),hs-CRP比较差异无统计学意义(P0.05)。3重症组撤机成功39例,撤机失败11例;撤机前血清PCT的ROC曲线下面积为0.812,最佳截点值为0.80 ng/m L,敏感度为82.0%,特异度为76.0%。结论血清PCT可以作为老年重症肺部感染患者的辅助诊断指标,且对患者撤机结局有一定的预测价值。     

超声小探头联合刷检现场细胞学对肺周围型病灶的诊断价值

目的探讨超声小探头(EBUS)联合刷检现场细胞学(C-ROSE)对肺周围型病灶的诊断价值。方法将EBUS送至需探查部位,以获得最佳的超声图像及最佳取材位置,退出超声探头。根据EBUS进入的路径,先行刷检,将刷检所取得的细胞标本分为两份,其中一份行刷检C-ROSE评估,当刷检C-ROSE为恶性时,则停止刷检,如果为无诊断价值时则需在原部位再次刷检或换部位进行刷检或停止刷检进行下一步活检,在每一个部位刷检结束后均行经支气管肺活检。结果 59例患者中,恶性患者43例,肺活检敏感度为55.8%(24/43),刷检细胞学诊断敏感度为81.4%(35/43),两者联合可提高肺癌诊断率,刷检C-ROSE假阳性0.0%,敏感度为74.4%(32/43),刷检C-ROSE结果与刷检细胞学结果一致性极好(Kappa值为0.902,P0.001)。病灶直径≥3 cm与3 cm的周围型肺癌刷检及联合活检的诊断率分别为88.9%和92.6%,68.8%和75.0%,差异无统计学意义(P0.05),各叶之间刷检及联合活检的诊断率差异无统计学意义(P0.05),当C-ROSE结果为阳性时平均刷检次数为(1.61±0.90),平均操作时间为(20.80±7.93)min;为阴性时平均刷检次数为(2.35±0.69),(26.60±7.22)min,两组间差异有统计学意义(P0.05),有5.1%(3/59)的肿瘤患者为经刷检C-ROSE提示后更换部位取材发现。结论 EBUS联合刷检C-ROSE在肺周围型病变诊断具有较高的诊断价值,刷检C-ROSE与最终病理结果有很好一致性,当刷检现场细胞为阳性时可减少气管镜操作时间、刷检等及其带来的并发症。     

Unilateral lower lung field opacities on chest radiography: a comparison of the clinical manifestations of tuberculosis and pneumonia

Background

The radiological manifestations of lower lung field (LLF) tuberculosis (LLFTB) are similar to those of LLF pneumonia (LLFP), making diagnosis challenging. The aim of this study was to determine if there are differences in the clinical manifestations of LLFTB and LLFP in patients with unilateral LLF opacities.

Methods

We performed a retrospective review of patient records to identify those with unilateral LLF opacities who were subsequently diagnosed with LLFTB or LLFP. We compared demographics, clinical manifestations, hematological data, and radiographic findings between the groups of patients.

Results

We identified 22 and 72 patients diagnosed with LLFTB and LLFP, respectively. Multivariate analysis revealed that age (odds ratio [OR] = 1.05, 95% confidence interval [CI] = 0.99–1.11, P = 0.072), lack of fever > 38 °C (OR = 9.04, 95% CI = 1.69–48.40, P = 0.001), duration of symptoms ≥ 7 days (OR = 4.57, 95% CI = 1.09–19.26, P = 0.038), and the lack of air bronchograms upon radiography (OR = 12.08, 95% CI = 1.98–73.64, P = 0.007) were significant predictors of LLFTB in patients with LLF opacities. We used these predictors to construct a mathematical model for predicting LLFTB in patients with LLF opacities.

Conclusions

Our findings suggest that older age, prolonged duration of symptoms, lack of fever > 38°C, and the absence of air bronchograms are more common in patients with LLFTB than patients with LLFP. These findings may help clinicians differentiate between LLFTB and LLFP and thus initiate timely and appropriate treatment.     

Utility of spiral CAT scan in the follow-up of patients with pulmonary Langerhans cell histiocytosis

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disease that occurs almost exclusively in smokers, generally young adults between 20 and 40 years old. Prognostic biomarkers of the disease are lacking. This study describes the clinical-radiological features of a group of PLCH patients and applies a semi-quantitative CT score of the chest to verify the prognostic value of radiological findings in this disease. Clinical-radiological and immunological data from 12 Caucasian patients (6M, 7 smokers and 5 ex-smokers, mean age 36±8 years) were recorded at onset and after a follow-up period of 4 years. Application of the semi-quantitative CT score revealed a prevalently cystic pattern at onset and follow-up in the majority of the patients. Patients with a prevalently nodular pattern developed cystic lesions during follow-up. Interestingly, significant correlations were found between the extent of cystic lesions and DLCO values at onset (time 0: p<0.05) and at the end of follow-up (time 1, p<0.05) and with FEV1 values at time 0 (p<0.05) and time 1 (p<0.05). Patients with progressive functional decline were those with CT evidence of severe cystic alterations. The results suggest that high resolution CT scan of the chest is mandatory for characterizing PLCH patients at diagnosis and during follow-up. The proposed CT score of the chest showed potential prognostic value.     

呼吸导引操在稳定期慢性阻塞性肺疾病康复中的价值

慢性阻塞性肺疾病(COPD)是一种死亡率呈上升趋势的慢性疾病。尽管抗炎、联合和靶向治疗取得了重要进展,但COPD药物治疗仍是治标不治本。肺康复是COPD管理过程的核心,运动训练则是肺康复的基石。传统导引术具有防病和治病的双重功效。现有研究表明,呼吸导引操可使稳定期COPD患者临床获益。本文将对COPD治疗现状、呼吸导引操在COPD患者康复中的价值作一综述。     

胎儿脑中线异常对产前诊断胎儿颅内发育异常的价值探讨

目的回顾性分析胎儿脑中线异常病例的产前声像图、胎儿MRI等影像学表现，探讨产前超声、MRI及其他辅助检查方法在产前诊断和鉴别诊断中的作用。方法应用中晚孕系统超声检查检出胎儿脑中线异常如大脑镰缺如、透明隔缺如、侧脑室及丘脑融合、第三脑室扩张、小脑蚓部缺如、小脑延髓池增宽、脑中线囊肿、脑中线偏移等，同时检出其他颅内、外结构异常，必要时加用MRI检查、染色体核型分析等进行进一步的诊断及鉴别诊断。结果产前超声共检出脑中线异常胎儿14例，根据产前超声、MRI、染色体分析结果诊断为前脑无裂畸形3例，其中2例为18号染色体异常；脑积水4例，其中2例合并其他异常；小脑延髓池增宽4例，其中1例为经典型Dandy-Walker综合征，2例合并心脏异常，1例随访至1岁未见异常；脑中线囊肿2例；脑实质出血致脑中线偏移1例。结论脑中线异常是多种胎儿颅内病变的主要超声表现之一，通过超声观察分析不同脑中线异常的特征、并结合其他颅内外伴发表现，以及MRI、染色体核型分析等结果，有助于对胎儿颅内结构发育异常进行更好的诊断和鉴别诊断。     

Evaluation of two automated systems for detection of bacteriuria

The Utiscreen-CORAL Biomedical system and ROBOBACT system were tested against conventional uroculture in blood agar and MacConkey agar as a reference method to determine the bacteriuria from 400 samples. For the Utiscreen-CORAL Biomedical system, a sensitivity of 92.5% was obtained. However, by the ROBOBACT system, the sensitivity was 69.9%.