Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance

Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.     

大鼠脂肪干细胞复合胶原-壳聚糖-硫酸软骨素三维支架构建组织工程软骨

Objective To evaluate the character of the collagen-chitosan-chondroitin sulfate scaffold seeded with rat adipose tissue-derived stromal cells. Methods A dipose tissue were harvested from 6 weeks old Wistar rats and the stromal cells were harvested by type Ⅰ collagenase and then cultured in vitro. Type Ⅰ collagen was fully mixed with chitosan, freeze-dried and cross-linked with chondroitin sulfate, then freeze-dried again and sterilized by ethylene oxide. The pore diameter, water content, porosity of the scaffold were tested. The adipose tissue-derived stromal cells were digested, seeded into the plates, scaffold, and cen-trifuged into pellet, and then induced into cartilage. MTT detection for cell proliferation was done. After 3 weeks, the cell morphology, and cell proliferation and adhesion were observed, and chondrngenic differenti-ation was also analyzed. Results The pore diameter, water content, porosity tested for the scaffold showed an appropriate form. Cell proliferation showed faster in the scaffold and pellet culture system after 5 day, there was still cell proliferation in the scaffold system after 14 days but no obvious changes in the pellet cul-ture system; ceils on the scaffold proliferated densely showed by histological staining, but there was a scaf-fold structure residues in the inner layer. The finding of type Ⅱ immunohistochemistry stain showed that cells express strong positive for type Ⅱ collagen in the scaffold and pellet culture system whereas it was weakly positive in the plate culture system; the specific mRNA for cartilage, type Ⅱ collagen, aggrecan and SOX-9 were expressed in all three systems showed by RT-PCR, but type X collagen was expressed continu-ously in the plate culture system and expressed after 21 days in the pellet culture system, whereas it was not detected in the collagen-chitosan-chondroitin sulfate scaffold system. Conclusion The parameters of the collagen-chitosan-chondroitin sulfate scaffold were suitable in our study. The results suggested that it can promote the adipose tissue-derived stromal cells proliferation and chondrogenic differentiation better than the plate and pellet culture systems and maintain the phenotype of chondrocytes well; it is the optimal choice for cartilage tissue engineering in the future.     

Point mutation in the parkin gene on patients with Parkinson’s disease

Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese. WANG Tao, male, born in 1961, Associate Professor This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial No. WJ 01529).     

烟雾病11例临床分析

自１９８５年至今，我院收治１１例经脑血管造影诊断的烟雾病患者。按照日本厚生省本病诊断标准，９例为确诊病例，表现为双侧颈内动脉末端、前动脉、中动脉起始部狭窄或闭塞，其中６例在双侧颅底可见烟雾状异常血管网，３例见单侧血管网；２例为可疑病例，仪表现为单侧上述异常改变。强调应严格烟雾病的诊断。本组采用颞浅动脉一硬膜脑贴敷术治疗患者１例，效果良好，结合日本该病治疗现状讨论，间接血行再建方法仍不失为烟雾病患者的合理治疗方法。     

中华眼镜蛇蛇毒对大鼠异种心脏移植超急性排斥反应的影响

试用中华眼镜蛇蛇毒消耗补体，观察其对豚鼠到ＳＤ大鼠异种心脏移植超急性排斥反应的影响。一次性给予小剂量ＣＣＶ腹腔注射后可明显降低大鼠血清补体溶血活性，４－２４小时后渐降至给药前１／２以下水平。ＣＣＶ可明显延长异种移植心脏４ 存活时间达２．５－３６小时，对照组仅为２５分钟；ＣＣＶ与脾切除，前列腺素Ｅ１联用可进一步延长移植心的存活时间，最长１例达４０小时。     

痛力克对癌症疼痛镇痛效果的临床观察

应用印度ＬＵＰＩＮ公司提供的痛力克（酮酷酸氨丁三醇 ）对中重度癌症疼痛３０例进行镇痛效果的临床观察，有效率９３％，平均显效时间９ｍｉｎ，均数缓解时间５．１ｈ，并用哌替啶做了同期交叉自身镇痛对比研究，结果表明：两药的镇痛效果相似（Ｐ＞０．０５），但痛力克的不良反应发生率明显低于哌替啶。     

Production and characterization of genetically engineered antibody molecules

Expression of antibody heavy- and light-chain genes by transfection permits the production of monoclonal antibodies with improved biological and antigen-binding properties. The immunoglobulin genes are placed in vectors containing a gene for encoding a protein that provides a biochemically selectable function in eukaryotic cells; these vectors are transfected into myeloma and hybridoma cells. Selection of drug-resistant cells permits the efficient isolation of the rare cells that express the transfected DNA. By placing heavy and light chains on plasmids with different selectable markers, one can deliver heavy- and light-chain genes simultaneously to the same cell. The transfected immunoglobulin genes are efficiently expressed and the proteins produced are a faithful mirror of the genes that were introduced. Using the standard techniques of genetic engineering and gene transfection, we can now produce antibodies of widely varying structures, including chimeric antibodies with segments derived from different species. These antibodies provide useful reagents to study structure-function relationships within the antibody molecule. Ultimately it will be possible to produce a new generation of antibody molecules with improved antigen-binding properties and effector functions.     

脑囊虫病人血清、脑脊液中抗体在MRI各期的变化

目的 检测脑囊虫病人血清和脑脊液中抗体在MRI各期的变化。方法 用抑制性ELISA法检测血清及脑脊液中的抗体。同时根据MRI表现将病例分为活动期、退变期、非活动期。结果 在69个病例中，脑脊液中抗体阳性率分别是：活动期75．00％，退变期62．50％，非活动期17.24％；血清中是81．25％、16．67％、22．22％。在相应各期中，脑脊液和血清抗体阳性率无显著性差别。结论 在影像学的不同时期抗体阳性率存在明显的变化。     

腹腔镜胆囊切除术中出血原因的分析与处理

目的:探讨腹腔镜胆囊切除术(LC)术中出血的原因与处理方法。方法:回顾性分析重庆医科大学附二院2004年12月~2006年3月所行LC术中出血的112例临床资料,总结探讨LC术中出血的原因与处理方法。结果:LC术中出血的原因有主观的和客观的因素,112例患者中5例中转开腹止血,余经重新施夹,电凝,缝扎,止血海绵填塞压迫,纱布压迫止血,肝镰状韧带悬吊等方法,成功地控制了出血。结论:术中出血是LC术中严重且最常见的并发症,分析出血的原因及相应措施,提出预防措施5条。     

Changes in total sodium intake do not lead to proportionate changes in total sodium removal in CAPD patients.

BACKGROUND: Dietary salt and fluid restriction is important in controlling fluid balance in patients on continuous ambulatory peritoneal dialysis (CAPD). However, it is often difficult to monitor patients' dietary total sodium intake (TSI). Usually, total sodium removal (TSR), the sum of urinary sodium removal (USR) and dialysate sodium removal (DSR), is suggested to represent TSI. In the present study, we investigated the reliability of using TSR as a surrogate to TSI in CAPD patients. METHODS: 40 clinically stable CAPD patients were closely followed for 3 months. Their TSI, USR, DSR, and fluid status were measured twice: at baseline and at the end of this study respectively. Fluid status was evaluated by bioimpedance analysis. Patients with increased sodium intake (group ISI) or decreased sodium intake (group DSI) (both >0.5 g/day or >21.74 mmol/day elemental sodium) were included in this study. RESULTS: There were 15 patients in group ISI and 9 patients in group DSI. During the follow-up, although TSI increased in group ISI and decreased in group DSI (p < 0.05), there were no significant changes in USR, DSR, or TSR in either group. No relationship was found between TSI and TSR. Changes in weight, blood pressure, urine volume, ultra-filtration, and small solute removal (Kt/V and creatinine clearance) were not statistically significant between the two groups. Fluid status deteriorated in group ISI and improved in group DSI (p < 0.05). CONCLUSIONS: Our study suggests that changes in total sodium intake do not lead to proportionate changes in total sodium removal in CAPD patients. Therefore, TSR (the sum of USR and DSR) should be used cautiously to monitor TSI in this patient population.