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Malcolm D. McGinnis Roger V. Lebo David L. Quinn Malcolm J. Simons 《American journal of medical genetics. Part A》1994,52(4):438-444
A 438 basepair intron 1 sequence adjacent to exon 2 in the human major histocompatibility complex DQA1 gene defined 16 allelic variants in 69 individuals from wide ethnic backgrounds. In contrast, the most variable coding region spanned by the 247 basepair exon 2 defined 11 allelic variants. Our phylogenetic human intron 1 tree derived by the Bootstrap algorithm reflects the same relative allelic relationships as the reported DQA1 exon 2 tree [Gyllensten and Erlich, Hum Immunol 36:1–10, 1989]. Thus 3′ DQA1 intron 1 and exon 2 have cosegregated since divergence of the human races. Comparison of human alleles to a Rhesus monkey DQA1 first intron sequence found only 10 nucleotide substitutions unique to Rhesus, with the other 428 positions (98%) found in at least one human allele. This high degree of homology reflects the evolutionary stability of intron sequences since these two species diverged over 20 million years ago. Because more intron 1 alleles exist than exon 2 alleles, these polymorphic introns can be used to improve tissue typing for transplantation, paternity testing, and forensics and to derive more complete phylogenetic trees. These results suggest that introns represent a previously underutilized polymorphic resource. © 1994 Wiley-Liss, Inc. 相似文献
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The effects of early family relationships on contemporary relationships and assistance patterns between adult children and their parents 总被引:1,自引:0,他引:1
We investigated the influence of early parent-child relationships on contemporary adult child-parent relationships and the effects of these relationships on the level of assistance between adult child and parent. A sample of 902 married men and women were questioned regarding their current relationships with their elderly parents, the level of assistance provided them, and the quality of their relationship with their parents when they were growing up. The findings indicated that early parent-child relationships and the characteristics of parents when adult children were growing up influenced contemporary adult child-parent relationships. In turn, the quality of the contemporary adult child-parent relationship was found to have a slight effect on assistance from adult children to their parents. 相似文献
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MR of a melanoma simulating ocular neoplasm 总被引:1,自引:0,他引:1
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郭战宏 《世界核心医学期刊文摘》2006,2(5):16-17
目的:研究在接受人工通气的新生儿中连续吗啡静滴对动脉血压的影响。设计:盲法随机安慰剂对照试验。机构:两个中心的三级新生儿重症监护病房。病例:共有144名接受人工通气的新生儿,入选标准为出生后年龄<3d、人工通气<8h并有留置动脉导管,剔除标准为严重窒息、严重脑室内出血、 相似文献
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The greatest catastrophy in sports is an athlete's unexpected sudden death. Identifying those athletes at risk remains a great challenge to physicians performing preseason examinations. Hypertrophic cardiomyopathy is the most common cause of nontraumatic sudden death in athletes. Most cases of this diseased heart are diagnosed easily by echocardiography. The case presented exemplifies the attention to detail required to differentiate the borderline diseased heart from the conditioned athletic heart. Once a diagnosis of hypertrophic cardiomyopathy is made, further participation in intense physical exercise is discouraged. This recommendation is necessary despite the unknown relative sudden death risk for the minimal criteria cases. 相似文献
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J W Slack R A Hyndiuk G J Harris K B Simons 《Ophthalmic plastic and reconstructive surgery》1992,8(2):143-149
A 37-year-old man with a recurrent papillomatous lesion of the upper eyelid and four separate bulbar conjunctival ulcers was found to have North American blastomycosis. This represents the first reported case with conjunctival lesions that were not simply contiguous with eyelid involvement. This case underscores the importance of considering blastomycosis in the differential diagnosis of granulomatous conjunctivitis and when examining a lesion of the eyelid resembling a squamous cell carcinoma or atypical papilloma. 相似文献
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Diabetic patients are at increased risk of cardiovascular disease, particularly when proteinuria is present. Lipoprotein(a)[Lp(a)] levels were assessed in 37 patients with insulin dependent (IDDM) and in 75 patients with non-insulin dependent (NIDDM) diabetes who showed varying degrees of proteinuria and glycaemic control. Median Lp(a) in 112 diabetic patients was significantly greater than in 116 healthy controls (113 vs 48 mg/L; p <0.01). 86 of the patients had first morning urine albumin concentration < 30 mg/L (normoalbuminuria = NA), 16 patients 30–200 mg/L (microalbuminuria = MA) and ten patients < 200 mg/L (albuminuria = ALB). There was no significant difference in median Lp(a) concentration between the three groups (NA = 108, MA = 163, ALB = 98 mg/L; p > 0.5). No significant difference in median Lp(a) concentration was found between patients with IDDM, NIDDM treated with insulin, or NIDDM treated with oral agents and/or diet (120, 98, 115 mg/L respectively; p > 0.7). When the 86 NA patients were divided on the basis of median fructosamine concentration (357 umol/L), no significant difference was found in median Lp(a) levels between those grouped below or above this median (98 mg/L vs 118 mg/L; p < 0.5). Across all diabetics studied there was no significant correlation present between Lp(a) and urinary protein or glycaemic control. These cross-sectional results suggest that median Lp(a) concentration is increased in both IDDM and NIDDM patients, but this increase is not related to the degree of proteinuria or short-term glycaemic control. 相似文献