A study of the relationship between the delivery to cord clamping interval and the time of cord separation

A randomised controlled trial of 554 women was carried out to compare the effects of late and early umbilical cord clamping on the time of cord separation. In addition data were collected on maternal and neonatal outcomes. There were no significant differences between the two groups in the duration of cord adherence and neonatal and maternal outcomes. There appeared to be a higher rate of jaundice in the late clamped group which did not reach statistical significance. There was an unexpectedly higher rate of breast feeding at home in the late clamped group which did reach statistical significance. Overall the trial provides no clear evidence for the benefit of early cord clamping (the current policy as part of the active management of the third stage in the UK) on the outcomes considered.     

淋巴细胞亚群微核表达的辐射效应研究

简述了淋巴细胞亚群微核检测方法、淋巴细胞亚群自发微核率和影响因素，以及关于电脑射效应的研究现状，为微核法用于辐射生物剂的未来发展提供了有益信息。     

Risk of lung cancer among patients with head and neck cancer

A cohort of 5180 patients with head and neck cancer, who were part of the tumor registry of the Surveillance, Epidemiology, and End Results area of western Washington State, was followed up for as many as 15 years to determine the risk of lung cancer. A sample of 522 patients from this cohort was interviewed to determine smoking history. Lung cancer developed in 356 (6.9%) of the 5180 patients. The overall annual incidence of lung cancer remained relatively constant between approximately 1.0% and 2.0% during the 15 years of follow-up. Men had an increased risk of lung cancer compared with women (relative risk [RR] = 1.56; 95% confidence interval [CI] = 1.18 to 2.03). Compared with patients with oral cavity cancer (RR = 1.00), the relative risk of lung cancer developing by the site of the index tumor was 0.63 (95% CI = 0.40 to 0.98) for lip, 1.12 (95% CI = 0.81 to 1.56) for intrinsic larynx, 1.73 (95% CI = 1.21 to 2.47) for oropharynx, 1.84 (95% CI = 1.16 to 2.92) for hypopharynx, and 2.28 (95% CI = 1.60 to 3.24) for extrinsic larynx. Among the 522 patients who were interviewed, men smoked more than women ( p < 0.0001), and patients with laryngeal or pharyngeal cancer smoked more than patients with cancer of the lip or the oral cavity ( p < 0.05). Among patients with head and neck cancer, the risk of lung cancer is highest for men and for patients with cancer of the pharynx or extrinsic larynx. These findings may be explained by differences in smoking consumption. (Otolaryngol Head Neck Surg 1997;116:630-6.)     

乳癌病人单次卡铂和阿霉素化疗诱发的染色体损伤和细胞生物学毒性

应用常规染色体畸变分析和胞浆分裂阻滞微核（ｃｙｔｏｋｉｎｅｓｉｓｂｌｏｃｋｍｉｃｒｏｎｕｃｌｅｉ，ＣＢＭＮ）法对１０例接受单次卡铂（平均剂量为４６２．９ｍｇ／ｍ２）和单次阿霉素（平均剂量为４８．１ｍｇ／ｍ２）化疗的乳癌病人血样进行了淋巴细胞染色体畸变（ｃｈｒｏｍｏｓｏｍｅａｂｅｒａｔｉｏｎ，ＣＡ）和微核（ｍｉｃｒｏｎｕｃｌｅｉ，ＭＮ）的观察分析，并通过有丝分裂指数（ｍｉｔｏｔｉｃｉｎｄｅｘ，ＭＩ）及核分裂指数（ｎｕｃｌｅａｒｄｉｖｉｓｉｏｎｉｎｄｅｘ，ＮＤＩ）观测了细胞毒性。结果表明，单次卡铂和阿霉素化疗均引起了ＣＡ和ＭＮ显著性增加，所观察到的ＣＡ主要为单体畸变，其中单体间隙（ｃｈｒｏｍａｔｉｄｇａｐ，ｃｔｇ）的增加最为显著，染色体型畸变未见显著性变化；卡铂引起ＭＩ明显减低，阿霉素对ＭＩ的影响不显著；两种化疗药物均未对ＮＤＩ产生显著性影响；通过ＭＩ及ＮＤＩ测量的细胞毒性之间显著性相关，但ＣＡ分析和ＣＢＭＮ法测得的染色体损伤之间缺乏相关性。     

膝关节 Q 角变化规律的实验研究

本研究利用精密三维位移测读仪，研究分析了Ｑ角的变化趋势，以及对髌股关节运动的影响。研究结果表明，Ｑ角是一空间夹角，随屈膝角的增大而增大。力线在平面上的投影所呈的平面夹角Ｑｐ也就是通常所指的Ｑ角，在屈膝１５°左右达最大，而在９０°左右达最小。整个屈膝过程中，ＱＰ在５°－１５°之间变化，变化幅度达１０°左右。     

运动训练对雄性大鼠垂体─性腺轴功能的影响

本研究通过使用自己制造的大鼠流动水游泳池，对雄性大鼠进行了６周递增负荷的游泳训练，以此来探讨运动训练对大鼠垂体－性腺轴功能的影响，结果显示：与安静对照大鼠相比，训练大鼠的一般状态较差，血清睾酮水平显著降低（Ｐ＜０．０５），血清睾酮／皮质酮比值平均降低了３０％以上；而血清ＬＨ和ＦＳＨ水平未见明显变化。通过对大鼠睾丸组织ＬＨ／ＣＧ受体的测定，显示运动训练虽未引起其最大结合量的改变，却能使其解离常数显著升高（Ｐ＜０．０５）。提示此种训练可能通过降低睾丸ＬＨ／ＣＧ受体对垂体分泌ＬＨ的亲和力，从而影响睾酮的合成。     

大叶牛奶菜孕甾甙成分研究

用硅胶层析及反相硅胶层析法，从大叶牛奶菜（MarsdeniakoiTsiang）抗生育活性的甲醇提取物中分离获得一孕甾四糖甙。经化学反应，波谱分析，酸碱降解及其水解产物的鉴定，确定其结构为12-0-cvnnamyl-dihydrosarcostin-3-0-β-D-glucopyranosyl（l→4）-0-3-0-methyl-6-deoxy-β-D-allopyranosyl(1→4)-0-β-D-oleandropyranosyl(1→4)-0-β-D-cymaropyranoside,命名为大叶牛奶菜甙庚（marsdekoisideG）。经系统文献检索证明其为首次自该植物中分离得到。     

Upper Airway Obstruction With Hypoxaemia And Sleep Disruption In Down Syndrome

Six of 12 children with Down syndrome (DS) tested by means of long-term tape-recordings of oxygen saturation, breathing movements and expired CO2 were found to have previously undetected and severe upper airway obstruction during sleep. In five cases the obstruction occurred in the pharynx and in the sixth it was due to bilateral choanal stenosis. When compared with age-matched controls, overnight tape-recordings showed episodes of abnormal arterial hypoxaemia and an abnormally elevated end-tidal CO2. Episodes of obstruction were most marked during sleep associated with a non-regular breathing pattern. Abnormal episodes of hypoxaemia were associated with continued breathing movements. Sometimes there was no airflow (complete obstruction); at other times airflow continued normally or was reduced in amplitude (partial obstruction). During episodes of partial or complete airway obstruction the inspiratory waveform showed a characteristic shape. These results show sleep-related upper airway obstruction to be an often undetected complication of DS and all necessary measures should be taken to overcome the obstruction when it reaches the stage of producing abnormal hypoxaemia. Choanal dilatation and tracheostomy were successful in treating two of the children. Tonsillectomy and adenoidectomy were successful for one child, but only of marginal benefit for two others.