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21.
Smoking habits in insulin-treated diabetics in Nottinghamshire (UK) and clinic-attending diabetics in Nottingham have been analysed. Compared with the general population, the prevalence of current cigarette smoking is significantly less (p less than 0.001) in both diabetic men and women older than 50 years. Fewer diabetic men over 60 years have ever smoked than in the general population (p less than 0.001) but this finding does not apply to diabetic women. While intervention probably plays some part in this lower prevalence, the most likely explanation is the multiplicative effect of both smoking and diabetes to produce high mortality risks. Actuarial analysis of insulin-treated clinic attenders diagnosed after 1970 showed that at most 14% (95% confidence interval [Cl] 9-18%) of the 183 who smoked at diagnosis had given up 5 years later while a minimum of 8% (95% Cl, 6-11%) of the 313 who were non-smokers had started smoking. Information about the patterns of smoking in patients with chronic disease is incomplete and it appears that too little is being done in clinical services which provide long-term management for these patients to either discourage smoking or determine why some patients give up smoking but others do not. 相似文献
22.
鼻咽癌高危人群微核特征研究 总被引:1,自引:0,他引:1
目的 观察鼻咽癌高危人群的主要细胞遗传学特征。方法 常规培养外周血淋巴细胞,检测鼻咽癌高危人群、鼻咽癌患者、鼻咽炎患者及正常人的微核率。结果 鼻咽癌高危人群及鼻咽癌患者的微核率明显增加,且随病情进展而继续增高。结论 鼻咽癌高危人群存在比较明确的细胞遗传不稳定性。 相似文献
23.
Njideka U Okubadejo James H Bower Walter A Rocca Demetrius M Maraganore 《Movement disorders》2006,21(12):2150-2156
Parkinson's disease (PD) occurs worldwide, but little is known about PD in Africa. We systematically reviewed publications on PD in Africa, with emphasis on epidemiologic and genetic studies. Articles published between 1944 and December 2004 were identified using several strategies. The studies emanated from 13 African countries (Kenya, Uganda, Tanzania, Ethiopia, Nigeria, Senegal, Ghana, Togo, Libya, Tunisia, Algeria, Zimbabwe, and South Africa). The publications fell into four categories: clinical series (n = 17), prevalence studies (n = 7), incidence studies (n = 1), and genetic studies (n = 3). The clinical series documented the occurrence of PD in Africa and described its clinical characteristics. The prevalence studies suggested some intracontinental geographic variation in PD prevalence. Overall, the prevalence figures and the incidence rates of PD in Africa appeared lower than those reported for European and North American populations. Few genetic studies of PD have been reported from Africa, and none in blacks. There are no case-control or cohort studies of PD reported from Africa. This review provides a summary of PD research in Africa over the past 60 years and highlights the information gaps and potential areas for future research. 相似文献
24.
K. P. Burdon C. D. Langefeld L. E. Wagenknecht J. J. Carr B. I. Freedman D. Herrington D. W. Bowden 《Diabetic medicine》2006,23(3):228-234
Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin‐angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima‐media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population. 相似文献
25.
目的克隆和鉴定日本血吸虫磷酸丙糖异构酶(SjTPI)编码基因,为寻找血吸虫病的候选疫苗联合应用打基础.方法设计合成引物,抽提日本血吸虫成虫总RNA,用RT-PCR法从中扩增出SjTPI基因编码序列,将其克隆入pGEM-T载体,用双酶切、以重组质粒为模板进行PCR扩增和测序进行鉴定.结果 RT-PCR法从成虫总RNA中扩增出大小为759 bp SjTPI基因编码序列,重组质粒pGEM-SjTPI经双酶切、PCR扩增,均可获得一条与RT-PCR产物一致的DNA片段,序列测定结果表明具有一个长度为759 bp的完整开放阅读框,与日本血吸虫(菲律宾株)和曼氏血吸虫磷酸丙糖异构酶核苷酸序列有高度同源性(分别为99%和88%).结论该实验成功地克隆了SjTPI编码基因,为进一步研究提供了条件. 相似文献
26.
J. Finsterer G. Miltenberger H. Rauschka A. Janecke 《European journal of neurology》2006,13(10):1149-1152
The objective of this study was to report a novel exon-1 mutation in the myelin protein zero (MPZ) gene, resulting in axonal Charcot–Marie–Tooth neuropathy with recurrent hyper-CK-emia. In a 64-year-old woman slowly progressive distal lower limb weakness, muscle cramps in the lower limb muscles, and stocking-type numbness had developed from the age of 61. Neurologic examination revealed discrete hip flexor weakness, weakness for foot extension, diffuse wasting of the distal lower limb muscles, reduced patella tendon reflexes, and absent Achilles tendon reflexes. There was recurrently elevated creatine kinase with a maximum of 607 U/l ( n , <145 U/l). Stimulation of the peroneal and tibial nerves did not evoke a muscular response. Electromyography was neurogenic. Biopsy of the right sural nerve showed diffuse axonal degeneration and loss of axons of all diameters. Muscle biopsy showed increased fiber-size variability, angulated fibers, internalized nuclei, accumulations of nuclei, grouped atrophic muscle fibers, and fiber splitting. Molecular genetic analysis by PCR and direct nucleotide sequencing revealed the heterozygous C59T exon-1 MPZ gene mutation, resulting in the amino acid exchange S20F of the MPZ signal protein domain (leader peptide). The novel C59T mutation in the leader peptide of the MPZ gene is pathogenic and manifests as severe, late-onset, axonal, symmetric sensorimotor polyneuropathy (CMT2) and hyper-CK-emia. 相似文献
27.
Association of angiotensin II type 1 receptor gene polymorphism with essential hypertension 总被引:15,自引:0,他引:15
The renin-angiotensin system is involved in control of blood pressure and salt and fluid homeostasis. Genes for components of this system have been of major focus in research on the causation of the common, complex, polygenic trait, essential hypertension (HT). Association of an A→C variant at nucleotide 1166 of the angiotensin II type 1 receptor (AT1 R) gene with HT, but an absence of linkage of this locus with this disease, has been reported recently. Since confirmation in a different setting is imperative, we performed a cross-sectional case-control study of the A1166C variant in a well-characterized group of 108 Caucasian HT subjects with a strong family history (two affected parents) and early onset disease. Genotyping was by mismatch polymerase chain reaction/ Bfr I restriction fragment length polymorphism analysis. Frequency of the C1166 allele was 0.40 in HTs and 0.29 in normotensives. The difference in genotype (χ2 = 13, P = 0.0015) and allele (χ2 = 5.3, P = 0.02) frequencies between the two groups was significant (odds ratio for CC vs AA+AC = 7.3 [95% CI, 1.9–31.9). The present results implicate the AT1 R gene, or a locus in linkage disequilibrium with the variant tested, in the causation of essential HT. 相似文献
28.
The normally expressed κ immunoglobulin light chain gene repertoire and somatic mutations studied by single-sided specific polymerase chain reaction (PCR); frequent occurrence of features often assigned to autoimmunity 下载免费PDF全文
L JUUL L HOUGS V ANDERSEN A SVEJGAARD T BARINGTON 《Clinical and experimental immunology》1997,109(1):194-203
The expressed human κ light chain gene repertoire utilized by healthy individuals was studied by two different single-sided specific PCR techniques to avoid bias for certain V genes. A total of 103 rearranged κ sequences from peripheral blood mononuclear cells from healthy individuals were cloned from cDNA and assigned to the Vκ and Jκ germ-line genes with the closest overall homology. The use of cDNA rather than genomic DNA focused the analysis on activated B cells rich in mRNA. Accordingly, the sequences represented the applied repertoire and almost all were somatically mutated. V genes from the Jκ-proximal duplication unit of the κ locus were almost exclusively used. A total of 65% of the sequences could be assigned to four or five genes: A27 (humkv325), L6 (Vg), L2 (humkv328), and A3 and/or A19. N additions and P nucleotides were quite common and found in 32% and 21% of the sequences, respectively. Extended CDR3s more than nine residues in length were found in 18% of the sequences, and in 71% of cases this was due to insertion of an extra proline residue. This proline was usually explained from the germ-line sequences involved. These results are in good agreement with those of previous repertoire studies using potentially V-gene-biased techniques. Thus, it is clear that restricted V-gene usage, common N and P additions, and extended CDR3 regions are normal features and not, as has been claimed, characteristics of pathological autoantibodies. 相似文献
29.
Fifty couples and their children with Down syndrome (D.S.) were typed for HLA-A and HLA-B antigens and compared to 50 control families and 464 blood donors. The parental origin of the extra chromosome 21 was determined by cytogenetic methods. All individuals were caucasians and there was no history of consanguinity. No excessive HLA sharing was present in D.S. parents. The mothers of D.S. shared no more HLA antigens with their D.S. children than the control mothers with their normal children (14% vs. 18%). Thirteen of the fifty pairs (26%) (parent in whom the nondisjunction occurred and D.S. child) shared three HLA antigens at the A and/or B locus. This was not significantly higher than the proportion in the control group (12/50 or 24%). These data suggest that it is not the sharing of HLA-A and HLA-B antigens between the parents or between the parent who was the origin of the nondisjunction and the D.S. child that is related either to the occurrence of trisomy 21 zygotes or to prenatal survival of affected embryos and fetuses. 相似文献
30.
Summary
In the last decades back pain has reached dramatic proportions in industrialized countries. Disorders of the back are nowadays
the leading cause of direct and indirect health care costs. Accurate prevalence estimates are needed to serve as a basis for
health care evaluations. A review of epidemiologic studies in the general population reveals that back pain has reached a
prevalence of 40 % for current pain. 7 to 18 % are “frequently”, “often”, “daily” or “constantly” affected. 75 % of the adult
population suffers from back pain during the last year. 80 to 90 % of the adult population in industrialized countries experience
back pain ever. Gender specific differences are only present in severe, chronic forms which are more often experienced by
women. Back pain has a prevalence maximum at 50 to 64 years. Older persons display lower prevalence estimates. The prevalence
maximum in men is one decade earlier than in women. There are several potential explanations for this prevalence pattern that
are discussed in the article. Back pain can be classified by location, temporal characteristics, pain intensity and pain history.
Currently, for none of these dimensions generally accepted, uniformly employed and validated definitions are available. In
most of the industrialized countries back pain is one of the most expensive symptoms. 75–90 % of the direct and indirect health
care costs were caused by those 5–10 % of patients who are disabled. As predictors of back pain a history of back pain and
job satisfaction play by far a more important role than the extensively studied mechanical factors. For a first episode of
back pain the prognosis is favorable. If the pain persist for more than three months the prognosis is unfavorable. After six
months of absenteeism because of back pain more than half of the afflicted never return to work. Rarely back pain is present
as a single symptom. In more than 80 % back pain is associated with pain in at least one joint. It remains to be studied if
back pain may be viewed as an entity or as part of a more complex pain syndrome.
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