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431.
432.
这是ICRP总委员会RH. Clarke博士根据即将出版的新建议书所学的概要,比较系统的扼要,抓住了重点。为此将全文译出,以飨读者。——译者注。  相似文献   
433.
Thiopurine methyltransferase alleles in British and Ghanaian populations   总被引:12,自引:0,他引:12  
Thiopurine methyltransferase (TPMT) catalyses the S-methylation of thiopurine drugs such as 6-mercapto-purine, 6-thioguanine and azathioprine. TPMT activity is inherited as an autosomal co-dominant trait, and several mutations in the TPMT gene have been identified which correlate with a low activity phenotype. Although ethnic differences in TPMT activity have been described, population frequency analysis of TPMT alleles has not been well defined in different ethnic groups. The frequency of four allelic variants of the TPMT gene, TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C were compared in British Caucasian (n = 199) and Ghanaian (n = 217) populations using PCR-RFLP and allele- specific PCR-based assays. TPMT*3C was found in 14.8% of Ghanaians (31 heterozygotes, one homozygote). The TPMT*2, TPMT*3A and TPMT*3B alleles were not detected in any of the Ghanaian samples analysed. In contrast, 10.1% of British subjects had variant alleles, consisting of TPMT*2 (n = 2), TPMT*3A (n = 17) and TPMT*3C (n = 1) alleles. The frequencies of mutant alleles in this study were 5.3 and 7.6% in British Caucasians and Ghanaians, respectively. Among Ghanaian tribes, Ewe subjects had a lower frequency of mutant alleles (5.9%) than Ga (13.2%) or Fanti (11.6%), although this did not reach statistical significance. This study provides the first analysis of TPMT mutant allele frequency in an African population and indicates that, unlike Caucasians, TPMT*3C is the most common allele in African subjects.   相似文献   
434.
Patients who have temporomandibular joint (TMJ) clicking and pain are assumed to have an anterior displacement of the meniscus with reduction on opening of the jaw. On the basis of this assumption, these patients are treated nonsurgically with splint therapy. Of 301 TMJs examined, 108 (36%) produced clinically audible clicks on opening, closing, or both. Fluoroscopy and arthrotomography studies for 16 (15%) showed anteriorly displaced menisci without reduction. The mean age of this group was 32 years, with a range of 17-51 years. The duration of the patients' symptoms ranged from three months to eight years (mean 3.7 years). Bilateral degenerative joint disease was noted in 8/16 (50%). Operative findings in four patients suggested the cause of the clicking sound as a frictional impact between the degenerated surface of the condyle and the hypertrophied displaced meniscus. These observations demonstrate that an audible click may not imply a reduction of a displaced meniscus.  相似文献   
435.
海南粗榧新碱衍生物HH07A的抗肿瘤作用   总被引:3,自引:0,他引:3  
用细胞生长曲线测定法及软琼脂集落形成分析法研究了HH07A对几种肿瘤及正常细胞生长的影响。结果表明,1.5ug·ml-1及3μg·ml-1HH07A能分别明显抑制L1210和HL-60细胞的生长。3种肿瘤细胞对HH07A的敏感性依次为L1210>KB>HL-60,而正常小鼠粒系祖细胞GM-CPC对药物的敏感性则低于前三者,且HH07A3.5μg·ml-1对HL-60细胞无分化诱导作用。HH07A对腹水型L1210白血病小鼠、S180小鼠均有较明显的治疗作用,使L1210荷瘤小鼠、S180荷瘤小鼠存活时间延长。也能抑制S180实体瘤的生长。  相似文献   
436.
437.
Duquesnoy  RJ; Filip  DJ; Aster  RH 《Blood》1977,50(3):407-412
Platelet transfusions from donors selectively mismatched for cross- reactive and certain non-cross-reactive HLA antigens were found to be more effective in HLA-A2 negative than in HLA-A2 positive, alloimmunized thrombocytopenic patients. The two groups of patients responded equally well to platelets matched for antigens of the HLA-A and B loci. Certain alloimmunized patients negative for HLA-A2 continued to respond satisfactorily to platelets selectively mismatched for non-cross-reactive HLA antigens as long as platelets containing HLA- A2 were avoided. The data indicate that platelet transfusion support can be provided within a broader range of donor-recipient HLA antigenic disparity to HLA-A2 negative alloimmunized patients than to those who are positive for this antigen.  相似文献   
438.
Clinical economics review: gastrointestinal disease in primary care.   总被引:2,自引:0,他引:2  
Gastrointestinal disorders are common in the general population, with annual prevalence figures ranging from 20% for irritable bowel syndrome to over 40% for dyspepsia. Less than one-third of patients consult general practitioners for these problems, and anxiety about serious disease and cancer are as important in the decision to consult as symptom severity. Gastrointestinal disorders have significant socioeconomic effects in the community, and account for 10% of the work of general practitioners in the UK. The health economics implications of management in primary care relate principally to the costs of investigation and therapy, notably antisecretory drugs, endoscopy, radiology and specialist referral. Although guidelines based on evidence and agreed between primary and secondary care physicians offer an attractive approach to rationalizing the use of resources, there is at present little health service research evidence on which to base important decisions. For example, in dyspepsia, the role of Helicobacter pylori identification and eradication in an overall management strategy in primary care has yet to be defined. An exploration of the clinical economics of gastrointestinal disorders in general practice raises a number of research questions, which will require the attention of both generalists and specialists.  相似文献   
439.
New charts for height, weight, height velocity, and weight velocity are presented for clinical (as opposed to population survey) use. They are based on longitudinal-type growth curves, using the same data as in the British 1965 growth standards. In the velocity standards centiles are given for children who are early- and late-maturing as well as for those who mature at the average age (thus extending the use of the previous charts). Limits of normality for the age of occurrence of the adolescent growth spurt are given and also for the successive stages of penis, testes, and pubic hair development in boys, and for stages of breast and pubic hair development in girls.  相似文献   
440.
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