Alterations in alanine metabolism in diabetic dogs during short-term treatment with an artificial B cell

Summary The flux rates of plasma glucose and alanine were studied isotopically (6-³H-glucose and U-¹⁴C-alanine simultaneously) in resting chronically diabetic dogs during short-term treatment with an artificial B cell where the insulin was infused into a peripheral vein. Despite perfect blood glucose control and normal glucose flux rates, the concentration and rates of appearance and disappearance of alanine were significantly elevated in the diabetic animals before, during and after an exogenous glucose load. The incorporation of the carbon moiety of alanine into circulating glucose was also increased, but diminished to a near-normal extent when exogenous glucose was given. The plasma clearance rates for alanine in the diabetic dogs were normal throughout the study. It is concluded that normal blood glucose control in diabetes does not necessarily mean normalization of the entire metabolic network. On the basis of peripheral hyperinsulinaemia alanine formation from glucose and branched chain amino acids is elevated in muscle. This may explain increased flux of alanine despite normal blood glucose control.     

通络胶囊治疗偏头痛的临床与实验研究

认为正气不足、病理体质为偏头痛的发病基础 ,以气血失调为主 ,寒热虚实错杂是本病的基本病机。据此确立扶正固本、祛风活络、化瘀止痛的治疗原则 ,拟通络胶囊治疗偏头痛 30例 ,与太极通天液治疗 30例对照 ,结果表明 ,治疗组愈显率 83.33% ,总有效率 93.33% ,与对照组相比有显著性差别 (P<0 .0 1) ,在改善兼症方面亦优于对照组 (P<0 .0 5或 P<0 .0 1) ,并能改善患者颅内血管功能状态。动物实验表明 ,通络胶囊能提高实验动物痛阈 ,同时提高大鼠下丘脑 5 - HT及 β-内啡呔水平 ,并能改善大鼠软脑膜微循环。     

Enzyme activities associated with the demyelinating phase of canine distemper

Summary Canine distemper, a naturally occurring viral disease of dogs which often terminates in parainfectious demyelination, was used as a model to study the role of acid proteinase, neutral proteinase and beta-glucuronidase in demyelination. These enzymes were higher in cerebella of dogs with distemper-associated demyelination than in age-matched controls. The highest elevations corresponded with the most severely demyelinated cerebella. The source of the increased enzymes activities was apparently unrelated to the lymphocytes present in areas of demyelination.The direct effect of distemper virus and serum on these enzymes was tested in canine glial monolayers. Virus infection resulted in lower enzyme activities in cells concomitant with the appearance of cellular lesions. There was a relative increase of beta glucuronidase activity in the media suggesting that distemper virus released pre-formed lysosomal enzymes. Serum which was obtained from dogs with distemper-associated demyelination and had previously demyelinated cerebellar explants, also decreased activities of all 3 enzymesin vitro.The 3 enzymes were measured in gerbil brains at various time intervals following unilateral cerebral infarction to determine if processes other than demyelination also caused these enzymes to be increased. Uncomplicated ischemic necrosis (24 h post infarction) did not alter the activities of these enzymes. Invasion of macrophages to ingest and digest necrotic tissue 10 days after infarction resulted in greatly increased acid proteinase and beta-glucuronidase, but unchanged neutral proteinase, activities.It was concluded that the increased activities of acid proteinase and beta-glucuronidase in demyelinated tissue probably are derived from macrophages ingesting damaged tissue. Neutral proteinase may be more specifically involved in the demyelinating process since this is partially located within myelin and can degrade the basic protein of myelin.Supported in part by Research grant Nos. GM 1052 and Al-09022 from National Institutes of Health Service, U.S. Public Health Service.     

对我校硕士研究生英语教学的思考

本文通过对我校硕士研究生英语水平的现状及存在问题的分析,从听、说、读、写等方面提出了对硕士研究生英语教学改革的思路。     

组织学实验课教学方法的探讨

目的　 探讨组织学实验课的教学方法 ,提高教学质量。方法　 在组织学实验课上 ,分别采用幻灯讲解、放映电视录像等方法对学生进行辅导 ;要求学生分别做绘镜下实像图、模式图、填图作业 ,在此基础上 ,组织学生进行讨论 ,并列表调查学生对上述 3种作业和 2种辅导的反映。结果　 赞成幻灯讲解辅导的人数 ( 71 % )显著地多于赞成放电视录像辅导的人数 ( 2 9% ) ,具有显著性差异 ( P<0 .0 0 1 )。 61 %的学生认为 ,在节约时间、检查发现学习的薄弱环节、增加复习面、调动学习积极性等方面 ,填图优于绘图。赞成做填图作业的人数 ( 94% )显著地多于赞成做绘图作业的人数 ( 4 % ) ,差异显著 ( P <0 .0 0 1 )。结论　 在目前的条件下 ,作为组织学实验课上的集体辅导 ,电视录像并不能完全代替幻灯讲解 ;让学生做填图作业 ,在节约时间、调动学习积极性、发现学习的薄弱环节、加深学习印象、增加复习的广度等方面明显地优于做绘图作业 ,值得在教学中推广。     

桑褐刺蛾幼虫致病物质成份的实验研究

为研究刺蛾幼虫致病性物质成分, 以探讨刺蛾幼虫皮炎的致病机理及其治疗。采用 “ Ｏ”号毛笔刺激刺蛾幼虫释放毒素, 再用０℃蒸馏水制备毒素洗脱液,并用考马氏亮蓝 Ｇ—２５０ 染色法检测该毒素洗脱液成分;然后用该洗脱液接种人体皮肤进行致病性研究。结果, 测得毒素洗脱液中有蛋白质存在; 该毒素洗脱液直接接种人体皮肤可致皮炎,若将其加热后再接种人体无致病作用,从而进一步证实该毒素洗脱液的致病物质为蛋白质类毒素。     

Single-handed practices – their contribution to an undergraduate teaching network in the first year of the new curriculum

OBJECTIVES: The new curriculum at King's College School of Medicine and Dentistry, which commenced in September 1996, requires all medical undergraduates to have a general practice placement throughout the 5 years of their medical education. DESIGN: This paper discusses recruitment, training and support of teaching practices for the new curriculum, reviews the distribution of single-handed general practices in the network and, via a selection of monitoring and evaluation procedures, discusses the implications of a policy which is inclusive of single-handed practices. The findings relate to the experience of the first semester of the first year of the new curriculum. It also examines the contributions that single-handed practices have made to the teaching network and the kind of support needed, if single-handed practices are to continue to contribute to the King's teaching network. SETTING: King's College School of Medicine and Dentistry. SUBJECTS: Medical undergraduates. RESULTS: The findings of this paper revealed that over a third of general practice provision is via single-handed practices in South-east London. Within the undergraduate teaching network, 10% of practices are single-handed. Students are welcomed and receive a learning experience comparable to those students in larger practices. Attendance at training events has proved difficult for some of these tutors, but the extra input from the department, in order to address this deficit, has not been onerous. Indeed, single-handed practices have not been unique with regard to difficulties in attendance at training events. CONCLUSIONS: The study concludes that single-handed practices can make satisfactory provision for undergraduates in the new curriculum and there is no evidence from this study to suggest otherwise.     

Antimetastatic action of the prostacyclin analogue cicaprost in experimental mammary tumors

Summary In breast cancer, the survival rate strongly depends on the number of lymph nodes involved. A drug with a specific inhibitory activity on lymph node and organ metastases would therefore be a candidate for adjuvant therapy after surgery. Prostacyclin and its stable analogues have been shown to interfere with certain steps of the metastatic cascade and to inhibit the number of lung colonies after i.v.-inoculation of various tumor cell lines. Our data reveal that cicaprost, a metabolically stable and orally active analogue of prostacyclin, has pronounced antimetastatic effects in a series of spontaneously metastasizing rodent tumors. In the SMT 2a and 13762 MTLn3 mammary carcinomas of the rat, cicaprost given daily from the day of tumor implantation strongly inhibits the number of lung metastases as well as lymph node weights without exerting an effect on the primary tumor. Even starting treatment when palpable primary tumors are present gives a pronounced antimetastatic activity. To demonstrate that cicaprost has an effect on metastases already settled in the respective organ, treatment was started after surgical removal of the primary tumor. In the SMT 2a tumor, a strong inhibition of the number of metastases was shown. Interestingly, a perioperative treatment schedule was also effective in both models used. As primary tumor growth in vivo or proliferation in vitro remained unchanged by cicaprost, its mode of action seems to be related to one or more mechanisms of the metastatic process. In tumor cell lines expressing a functional prostacyclin receptor, stimulated tumor cell migration is inhibited and changes of differentiation status are obvious. In conclusion, cicaprost strongly inhibits lymph node and organ metastases of spontaneously metastasizing rodent mammary tumors with a mode of action different from cytostatic or antihormonal drugs.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb.