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991.
A significant minority of medical and dental students fail their undergraduate courses. Early warning systems (EWSs) have been developed in some areas of higher education to predict 'at-risk' students at an early remedial stage. An attempt is made to develop an EWS to predict failure in the bacteriology component of the Batchelor of Dental Surgery course at Manchester Dental School. A system based on class tests and previous end-of-year performance is derived which is used to predict those students likely to fail or fall in the bottom 20-25% in their finals examination. The predictors are combined by a simple equal weights method, which is found to have the same predictive power as using multiple regression. Failure was correctly predicted in 60% of cases, at the expense of 71% false alarms. The high number of false alarms reflects the low failure rate rather than the lack of predictive information. The need for effective cross-validation of EWSs is discussed; many previous studies have not been tested on independent data. 相似文献
992.
N. J. GOODERHAM S. MURRAY A. M. LYNCH R. J. EDWARDS M. YADOLLAHI-FARSANI C. BRATT K. J. RICH K. ZHAO B. P. MURRAY S. BHADRESA S. J. CROSBIE A. R. BOOBIS & D. S. DAVIES 《British journal of clinical pharmacology》1996,42(1):91-98
1 Heterocyclic amines are formed in parts per billion levels when meat is cooked.
2 The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food.
3 We have shown that MeIQx and PhIP, both in vitro and in vivo , are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines.
4 MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt , we have shown that PhIP induces a characteristic mutational 'fingerprint'.
5 MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats. 相似文献
2 The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food.
3 We have shown that MeIQx and PhIP, both in vitro and in vivo , are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines.
4 MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt , we have shown that PhIP induces a characteristic mutational 'fingerprint'.
5 MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats. 相似文献
993.
Francine Ratner Kaufman Mary Halvorson Neal D. Kaufman 《Diabetes research and clinical practice》1995,30(3):205-209
Objective: To determine if uncooked cornstarch, as part of the evening snack, can avert nocturnal hypoglycemia in type 1 diabetes. Research Design and Methods: Fifty-one campers and counselors at the American Diabetes Association Camp in San Bernardino, CA were randomly assigned to receive 5 g of uncooked cornstarch as part of the 21:00 evening snack vs. a standard snack of equivalent carbohydrate content. Each snack was given for five nights and the participants and medical personnel were blinded as to assignment. Midnight and 07:00 finger stick blood glucose levels were compared with values <60 mg/dl defined as hypoglycemia and values >250 mg/dl defined as hyperglycemia. Results: There were 218 midnight and 222 07:00 values for comparison. There were six episodes of hypoglycemia at midnight and nine episodes of hypoglycemia at 07:00 for the cornstarch snack nights vs. 30 hypoglycemia episodes at midnight and 21 at 07:00 for the standard snack nights (P < 0.001 and < 0.05, respectively). There was no difference in the number of hyperglycemic events at midnight or 07:00 for the cornstarch vs. standard snack nights. At midnight, 12% of campers had hypoglycemia after the cornstarch snack vs. 46% after the standard snack (P < 0.001), and at 07:00, 16% had hypoglycemia after cornstarch vs. 26% after the standard snack (P = 0.327). Conclusions: These data suggest that uncooked cornstarch, as part of the evening snack, can diminish the nighttime and morning hypoglycemia associated with type 1 diabetes, without causing hyperglycemia. 相似文献
994.
在股骨颈移位骨折的治疗中,试用了7种不同的闭合复位方法。其中Whitman's法在骨折床台上进行,正常肢体外展,患肢由屈曲牵引至完全伸直位后,维持牵引并外展到与对侧肢体相称位,单髋人字石膏外固定(1914年)。 Leadbetter's法也在骨折床台上进行。将患肢髋部屈曲90°,沿大腿轴线行手法牵引。同时股骨干稍内收,患肢缓慢行环形活动至外展、内旋位,患肢向下降至骨折床台面时,行跟掌试验以验证是否完全复位(1933年)。 Bozan's法利用骨折床台使双下肢维持在伸直位,大绷带放置在患肢髂嵴部位,小绷带放置在患肢腹股沟皱襞最高点处实施牵引。然后整个患肢极度内旋,在维持侧方牵引的同时,患肢外展并轻度过牵(1934年)。 相似文献
995.
Demetrius M Maraganore Matthew J Farrer Timothy G Lesnick Mariza de Andrade James H Bower Dena Hernandez John A Hardy Walter A Rocca 《Movement disorders》2003,18(11):1233-1239
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene. 相似文献
996.
目的 近年来,叶轮血泵的研究已经成为心脏外科和生物医学工程领域关注的焦点.通过体外模拟循环实验台对自行研发设计的微型轴流血泵进行测试,探讨血泵的体外流体力学特性.方法 分别利用水及30%甘油水溶液作为循环介质模拟血液在体外模拟循环条件下进行血泵流体力学测试.结果 在血泵转速为13000 rpm,压力为100 mmHg时,分别以水及30%甘油水溶液作为循环介质.其对应流量达到6.19 L/min和5.08 L/min.结论 该轴流血泵的基本流体力学性能良好,其流体力学特性已经完全可以替代左心室功能,满足临床心衰患者辅助循环需求. 相似文献
997.
104例甲亢临床资料显示,胃肠道症状(多食易饥69%、食后腹胀38%,恶心呕吐19%、大便改变67%)的出现率颇高。23例患者及70名对照组健康人检测体表胃、结肠电,2,232序列频谱分析结果显示:1.甲亢患者,尤其有恶心、呕吐、返酸症状者,其空腹活跃期胃电活动指数倾向或明显高于正常,提示空腹胃运动亢进;2.有食后腹胀或更兼有纳差的甲亢患者,其餐后10~20min内胃电活动量达到最大值的百分例数及活动指数低于正常,进餐反应延缓并减弱;3.腹泻或便烂的甲亢患者,其各段结肠低、高频段的肠电活动量均较健康人大便软条者明显降低,提示①结肠平滑肌张力减低、腔内压降低,可致内容物肛向移动阻力减小;②起挤压搅拌作用的局限性运动减弱,与大便不成形关系密切;4.便烂兼有肠激惹征的甲亢患者,其空腹升、降结肠肠电异常活跃,餐后降结肠肠电活动亢进,与激惹性大使改变有关;5.便硬兼有肠激惹征的甲亢患者,空腹升、降、乙状结肠安静期低频段肠电活动量高于正常,提示起挤压搅拌、促进水分吸收的结肠活动增加,而餐后升结肠的肠电活动量异常增高,则可能是对硬便的代偿性反应。上述结果能解释甲亢患者有关胃肠道症状的某些发生机制。 相似文献
998.
面部色素痣较常见于鼻、颊、额、颧区,部分病变累及一侧面部的多个区域。这些病变手术切除后的缺损主要采用全厚皮片移植、直接拉拢缝合或邻近皮瓣整复。 相似文献
999.
作者选择乙基纤维素、聚乙烯醇等高分子材料制成涂膜剂,用大鼠皮进行双氯灭痛药膜的体外透皮速率测定。结果表明,氮酮与丙二醇可以促进药物渗透。不同的高分子材料可影响药物的扩散与释放,从而影响其透皮速率。与无膜无促透剂处方相比,药物在乙基纤维素中的透皮速率没有增加,在聚乙烯醇膜中的透皮速率有显著增加。 相似文献
1000.
Nobutaka Eiraku Shinji Ijichi Shinji Yashiki Mitsuhiro Osame Shunro Sonoda 《Journal of neuroimmunology》1992,37(3):223-228
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality. 相似文献