应用ROC曲线评价DR后处理技术对胸部影像的影响

目的:运用ROC曲线,探讨DR胸部摄影最佳的影像后处理技术。方法:使用DR系统设置的正常胸部摄影条件,对胸部体模与专用于X线摄影的ROC曲线评价体模(TRG)进行组合并曝光。分析未使用后处理技术及使用不同后处理技术,对DR胸部摄影胸片影像的影响。结果:使用单纯噪声消除技术、噪声消除加图像反转及噪声消除加全屏放大三种后处理技术所得的ROC曲线下面积Az值依次为0.85、0.825及0.925,均明显大于未使用后处理技术的面积Az值0.6;单纯噪声消除技术获得的ROC曲线下面积略大于噪声消除加图像反转技术的面积;噪声消除加全屏放大技术获得的ROC曲线下面积Az值最大。结论:应对胸部原始影像实施后处理调节。单纯噪声消除技术可明显增加影像的信息量,若在噪声消除基础上实施全屏放大技术,可获得DR胸部摄影的最大影像信息量。     

深圳市青少年心理叛逆的相关因素探讨

目的 了解深圳市青少年心理叛逆的表现并探讨其影响因素，为预防心理叛逆提供相关理论依据。方法 2005年3月至5月，采用分层整群随机抽样方法，选取19所深圳市大、中学校学生4000名，进行青少年心理叛逆的相关表现及行为调查。结果作为心理叛逆的表现之一，20．8％的深圳市青少年近一年有过离家出走的想法，5．8％的人曾经尝试过离家出走，其中男生尝试离家出走率为7．4％，女生为4．3％。初中／高中学生离家出走想法的发生率高于大学生（x^2=51．1，P=0．000），但不同学校类型问尝试离家出走的差别无统计学意义（x^2=1．9，P=0．392）。在过去12个月中孤独感、在过去12个月中失眠的次数、在过去12个月中是否连续两周感到伤心或绝望、网络成瘾、在过去1个月中平均每天的吸烟量、在过去1个月中平均每天的饮酒量是尝试离家出走的危险因素，而女生、学习成绩好是其保护因素。结论 深圳市大、中学生心理叛逆较普遍，他们中离家出走想法和尝试离家出走的发生率较高，常与社会心理因素有关，消除危险因素，加强健康教育可最大限度预防青少年的心理叛逆。     

Can Electrocardiographic Criteria Predict Adverse Cardiac Events and Positive Cardiac Markers?

OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.     

Effects of cerulenin on the endogenous fatty acid synthetic activity in squamous cell carcinoma of the oral cavity.

PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs.     

肺炎衣原体抗体效价与多发性硬化的相关性探讨

目的 探讨肺炎衣原体（Chlamydia pneumoniae）感染在多发性硬化（MS）发病和进展中的作用和致病机制。方法 选取急性期MS患者31例，缓解期MS患者28例及其他神经系统疾病患者30例，健康对照者30名，应用酶联免疫吸附试验测定患者和对照者血清及脑脊液中肺炎衣原体IgG和IgM抗体水平。结果 急性期MS组、缓解期MS组、其他神经系统疾病组和健康对照组的肺炎衣原体血清IgG分别为48．4％、35．7％、30．0％、23．3％；4组IgM抗体效价分别为12．9％、14．3％、20．0％、10．0％，总体比较差异无统计学意义（P〉0．05）；急性期MS组与其他神经系统疾病组的脑脊液IgG和IgM抗体效价分别为0、6．7％和0、0，差异无统计学意义（P〉0．05）。结论 肺炎衣原体的感染或重复感染与MS发病相关不紧密，可能仅为MS的伴随感染。     

神经干细胞超顺磁性氧化铁纳米粒子标记和体内MRI示踪

神经干细胞（neural stem cell，NSC）是当今医学的前沿课题，困扰其临床应用的一个难题是如何对移植进入体内的神经干细胞进行监测，观察其存活和迁徙的情况。在中枢神经系统的不同病理、生理条件下，移植的神经干细胞有着不同的迁徙和分化能力，对干细胞这一特性的研究目前多为在移植后的一定时间内处死实验动物，对神经组织进行切片。而这些侵袭性的方法，不能对神经干细胞在同一动物体内的迁徙、增殖情况进行动态的观察，故需要非侵袭的手段来对移植入体内的神经干细胞进行监测。     

98例尿道下裂手术的体会

目的通过对尿道下裂手术的改进,进一步完善尿道下裂手术的技巧和护理。方法A组50例尿道下裂Ⅰ期成形术中,采用皮下连续内翻缝合形成新尿道,且固定于阴茎海绵体,由阴茎根部自下而上多层次,多点缝合皮瓣皮下组织至阴茎海绵体上,均无间隙和死腔。B组48例采用常规手术方式作对照。结果A组50例尿道下裂Ⅰ期成形术成功44例,B组48例成功17例,A组与B组相比成功率显著提高(P＜0．05)。结论尿道下裂Ⅰ期成形术成功率关键在于术者对术式掌握的熟练程度和术中及术后对每个细节的认真处理。     

Synthetic/secreting and apoptotic phenotypes in renal biopsy tissues from hypertensive nephrosclerosis patients.

The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis.     

霍奇金病继发皮肤病变伴EBV编码的潜伏膜蛋白染色阳性1例报道

霍奇金病皮肤受累在H IV阳性患者少见。尽管这些病例中大多数的发病机制与Epstein-Barr病毒(EBV)相关,但很少有研究来证实霍奇金病皮肤受累的病毒致癌基因。作者报道1例H IV阳性男性患者,伴有侵袭性霍奇金病和特殊皮肤受累。皮损和淋巴结取样发现对EBV编码的潜伏膜蛋白呈阳性反