Morphology of the Cardiac Conduction System in Patientswith Electrophysiologically Proven Dual Atrioventricular Nodal Pathways

Conduction System in Dual AV Nodal Pathways. Introduction: Although the electrophysiologic criteria for dual atrioventricular nodal pathways are well established, the anatomical substrate is still unclear.
Methods and Results: We examined the hearts from 10 patients who had been studied electrophysiologically prior to cardiac transplantation. All 10 patients were male, aged 22 to 60years. Nine of the 10 patients had dual atrioventricular nodal pathways according to acceptedcriteria. Histologic studies of the atrioventricular conduction system showed normal structureof the atrioventricular node in all 10 hearts, with minor variations within the node in 3 cases, within the penetrating bundle in 3 cases, and within the nonbranching bundle in 3 cases. Theatrial approaches to the atrioventricular node were generally scanty in 6 hearts. The solitarycase that was shown electrophysiologically to lack dual pathways had no obvious difference inthe structure of the nodal area other than sparsity of transitional cells. We were unable tolocate any extranodal atrial tracts as described by other investigators.
Conclusion: The anatomical substrate for conduction over dual pathways may he too subtleto be detected by gross morphologic studies. Since dual pathways were unmasked in allpatients but one during electrophysiologic studies, it may be that the potential for these pathways is ubiquitous.     

GADD45β基因表达诱导对不同p53状态的肝癌细胞作用

目的：体外合成GADD45β基因全序列表达质粒后，研究GADD45β基因表达诱导对呈不同p53状态的肝癌细胞的作用及可能机制。方法：采用RT-PCR法获得GADD45β基因全序列，插入pDrive穿梭克隆载体和pIRES2-EGFP荧光表达载体后大量扩增获得DNA，结合p53全基因表达质粒pp53-EGFP转染HepG2、Hep3B细胞后，以[^3H]胸腺嘧啶脱氧核苷掺入法(^3H—Tdr)和细胞克隆形成法分析DNA合成变化及细胞生长能力；以双抗体夹心ELISA法测定TGF-β1表达变化。结果：成功合成GADD45β基因全序列和表达质粒，通过流式细胞仪收集转染阳性的荧光表达细胞能显著提高转染效率；转染GADD45β后．具有野生型p53基因的HepG2细胞的细胞克隆形成能力和DNA合成能力明显受到抑制，细胞凋亡明显增加，TGF-β1的表达亦明显受抑。与之相反，缺失p53基因的Hep3B需要同时共转染p53基因后，方出现抑制效应。结论：GADD45β基因能够有效抑制肝癌细胞的生长．其功能需要完整p53基因的辅助和(或)调控。GADD45表达和（或)功能异常，导致p53介导的DNA损伤修复途径异常或阻断，是肝脏细胞恶性转化及形成肿瘤的可能机制。     

Bacterial Colonization and Neonatal Infections

In a prospective randomized study different regimens for skin and umbilical disinfection in newborn infants were tested: daily whole body soap wash (control group), daily whole body soap wash and umbilical cleansing with (i) benzine solution, or (ii) 0.05 % chlorhexidine, and daily whole body wash and umbilical cleansing with a 4 % chlorhexidine detergent solution (Hibiscrub^®). Bacterial cultures were taken from the nose and umbilical area at discharge. Clinical infections were registered in the nursery, and after discharge until 6 weeks of age. Cultures were taken from infected areas. In the control group a high colonization rate was found for S. aureus (91 %), E. coli (39 %), and group B streptococci (GBS) (20 %). The colonization rates were influenced by the Hibiscrub regimen (colonization rate for S. aureus 59 %, E. coli 23 %, and GBS 10 %), but not by the other regimens. Infections (pemphigus, paronychia, conjunctivitis, umbilical infection) occurred in 12.9 % of the infants, of whom 65 % got infection after discharge from the nursery. 96 % of the infections were caused by S. aureus, and 87 % caused by strains colonizing the infants in the nursery. None of the tested regimens reduced the rate of infections during the first 6 weeks of life.     

The Development of General Practice in China

The concepts and principles of general practice are consistentwith Chinese cultural values; the leading authorities at theGeneral Practice Training Centre are extremely enthusiasticabout the general practice movement; the Ministry of PublicHealth is totally supportive of the general practice training;the medical/allied health professionals are eager to participatein general practice activities; and general practice certainlyis responsive to public expectations. General practice willbe flourishing and prosperous in China; however, there may betimes when the specialty of general practice in China experiencesgrowing pains with obstacles. The experiences gained from thedevelopment of general practice training programmes in Taiwanand other countries to handle the obstacles are of tremendousvalue to the development of general practice in China. It isexpected that communication and exchange between the generalpractice educators of Taiwan and China will play an importantrole in the further development of general practice in China.     

中国乌头的研究——Ⅸ.川乌、附子中的生物碱

作者对中药川乌的生物碱进行研究,从其中共分得六种结晶性的生物碱,并证明四种是已知物,卽次乌头碱(hypaconitine)、乌头碱(aconitine)、新乌头碱(mesaconitine)和塔拉地萨敏(talatisamine).另二种为新生物碱,暂称为川乌碱甲和川乌碱乙.川岛碱甲,熔点111℃,实验式为C₂₃H₃₇NO₆;川乌碱乙,熔点185℃,实验式为C₂₂H₃₅NO₄。另在附子中亦分得新马头碱及次乌头碱.