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991.
75 children aged under 15 years have entered the regular haemodialysis/renal transplant programme at Guy's Hospital in the 10 years since its inception; 13 children have subsequently died. A combination of hospital and home haemodialysis and renal transplantation was used. 64 children received 80 renal allografts; 37 1st grafts were from live, related donors and 27 were from cadaver donors. The 5-year acturial patient survival for the whole group and for those who had transplants was 76%. Live donor graft survival was 65% at 3 years, and 55% at 5 years; 1st cadaver graft survival was 42% at 3 years. Results obtained during the last 6 years of the 10-year period showed an improvement with a live related donor graft survival rate of 71%, and a 1st cadaver graft survival rate of 47% at 3 years. Particular experience was gained with home haemodialysis and live, related donor transplantation. Despite growth, and psychosocial and rehabilitation problems, the overall results were encouraging, particularly for the 46 children who had successful transplants. These children grew better, had fewer psychosocial difficulties, and were rehabilitated more successfully into normal life than those on long-term dialysis. We conclude that dialysis and transplantation should be offered to all suitable children with terminal renal failure.  相似文献   
992.
A controlled trial of azathioprine treatment of steroid-responsive frequent-relapsing nephrotic syndrome of childhood failed to show a therapeutic effect on the stability of remission after withdrawal of corticosteroid treatment.  相似文献   
993.
Ig repertoires generated at various developmental stages differ markedly in diversity. It is well documented that Ig H chain genes in human fetal liver are limited with regard to N-regional diversity and use of diversity elements. It is unclear whether these characteristics persist in pre-B cell H chain genes of adult bone marrow. Using Ig H chain CDR3 fingerprinting and sequence analysis, we analyzed the diversity of Ig H chain third complementarity determining regions (HCDR3) in adult bone marrow pre-B and mature B lymphocytes. Pre-B cell HCDR3 sequences exhibited adult characteristics with respect to HCDR3 size, distribution of N regions and usage of diversity elements. This suggested that pre-B cells in adults are distinct from fetal B cell precursors with regard to Ig H chain diversification mechanisms. At the DNA sequence level, HCDR3 diversity in mature B cells was similar to that in pre-B cells. Pre-B HCDR3s, however, frequently contained a consecutive stretch of hydrophobic amino acids, which were rare in mature B cells. We propose that highly hydrophobic pre-B HCDR3s may be negatively selected on the basis of structural limitations imposed by the antigen binding site. At the same time, usage of hydrophilic HCDR3 sequences (thought to support HCDR3 loop formation) may be promoted by positive selection.   相似文献   
994.
Cerebral cavernous malformation (CCM) is a Mendelian model of stroke, characterized by focal abnormalities in small intracranial blood vessels leading to hemorrhage and consequent strokes and/or seizures. A significant fraction of cases is inherited as an autosomal dominant trait with incomplete penetrance. Among Hispanic Americans, virtually all CCM is attributable to a founder mutation localized to 7q ( CCM1 ). Recent analysis of non-Hispanic Caucasian kindreds, however, has excluded linkage to 7q in some, indicating at least one additional CCM locus. We now report analysis of linkage in 20 non-Hispanic Caucasian kindreds with familial CCM. In addition to linkage to CCM1, analysis of linkage demonstrates linkage to two new loci, CCM2 at 7p13-15 and CCM3 at 3q25.2-27. Multilocus analysis yields a maximum lod score of 14.11, with 40% of kindreds linked to CCM1, 20% linked to CCM2 and 40% linked to CCM3, with highly significant evidence for linkage to three loci (linkage to three loci supported with an odds ratio of 2.6 x 10(5):1 over linkage to two loci and 1.6 x 10(9):1 over linkage to one locus). Multipoint analysis among families with high posterior probabilities of linkage to each locus refines the locations of CCM2 and CCM3 to approximately 22 cM intervals. Linkage to these three loci can account for inheritance of CCM in all kindreds studied. Significant locus- specific differences in penetrance are identified. These findings have implications for genetic testing of this disorder and represent an important step toward identification of the molecular basis of this disease.   相似文献   
995.
目的 探讨胶质母细胞瘤(glioblastoma,GBM)发病的分子遗传学机理,确定GBM的发生发展主要和哪些染色体或染色体区域有关,哪些染色体区域上可能存在与GBM相关的肿瘤抑制基因(tumor suppressor gene,TSG)。方法 应用聚合酶链反应技术,采用荧光标记的引物和377型DNA序列自动分析仪,对21例GBM的所有22对常染色体上共计382个微卫星位点进行了杂合性丢失(loss of heterozygosity,LOH)分析,相邻2个微卫星位点之间的平均遗传学距离为10cM。结果 在所有被检测的染色体臂上都观察到LOH,其中以染色体10q、10p、9p、17p和13q的LOH率最高(>50%),这些染色体臂上已知的肿瘤抑制基因PTEN、DMBT1、p16、p53和Rb所在区域LOH率都较高;14q、3q、22q、11p、9q、19q上也存在较高的LOH率(>40.5%);首次发现多个共同微小丢失区域:9p22-23、10p12.2-14、10q21.3、13q12.1-14.1、13q14.3-31、17p11.2-12、17p13、3q24-27、11p12-13、14q31-32.3、14q21-24.1、22q13.2-13.3、4q35、4q31.1-31.2、6qtel、6q16.3。结论 GBM存在复杂的遗传学异常,涉及多条染色体臂。以10q、10p、9p、17p和13q的异常与GBM发生发展的关系最为密切。除了已知的肿瘤抑制基因PTEN、DMBT1、p16、p15、p53和Rb外,首次所发现的多个微小共同丢失区域上可能存在GBM相关的多个未知TSG。  相似文献   
996.
In this study when patients were followed up for post-operative symptoms, it was seen that the incidence of narrowing of lumen of the common bile duct was more in cases where the operation was done by retrograde cholecystectomy with clean dissection of Calot''s triangle. Though this was a coincidental finding, it raises a doubt whether the narrowing is a result of impairment of blood supply to the common bile duct, which may result from clean dissection and display of Calot''s triangle area. The above dissection removes the fascial layer over the common bile duct and is likely to result in damage to end-arteries piercing through it to the common bile duct. This conjecture requires further study in a larger series.KEY WORDS: Cholecystectomy, Calot''s triangle, Surgical technique, Common bile duct stricture  相似文献   
997.
We examined the role of leukocyte function-associated antigen (LFA)-1 and its counter-receptor intercellular adhesion molecule (ICAM)-1, one of the most important pairs of adhesion molecules, in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Immunohistochemical study showed hyper-expression of ICAM-1 on vascular endothelial cells and expression of LFA-1 on mononuclear infiltrating cells in the spinal cords of TMEV-infected mice. Treatment with mAb to ICAM-1 and/or LFA-1 molecules resulted in significant suppression of the development of demyelinating disease, both clinically and histologically, with down-regulation in the CNS of the respective adhesion molecules after treatment. In mice treated with these mAb, the specific delayed-type hypersensitivity and T cell proliferative responses for TMEV were decreased. The production of tumor necrosis factor-alpha and IFN-gamma in spleen cells was also decreased, but IL-4 production remained unchanged. These data suggest that ICAM-1/LFA-1 interaction is critically involved in the pathogenesis of TMEV-IDD and that antibodies to these adhesion molecules could be a novel therapeutic approach to the treatment of demyelinating diseases such as human multiple sclerosis.   相似文献   
998.
Abstract Setting the terms of praise‐ and blameworthiness has long dominated philosophers’ discussions of responsibility. Analytic philosophy has most often looked to reason and the abstract relations between individual rational judgements and actions to advance the discourse on moral responsibility. Those whose capacity for reasoned judgement is impaired are deeply problematic. Is it proper to morally appraise ‘the mentally ill’? The philosopher T.M. Scanlon discusses moral responsibility as a precondition of moral appraisal and contends that it is not appropriate to appraise a person as (morally) praise‐ or blameworthy if that person cannot be held responsible for the action(s) for which he is being praised or blamed. What are the conditions, then, under which one can properly be said to be responsible for one's actions? Can one hold ‘the mentally ill’ responsible for their actions? If not, can it in any way be reasonable to expect them to ‘take responsibility’ for their actions and/or characters? The expectation that ‘the mentally ill’ will attempt to control, i.e. take responsibility for their behaviour despite the fact of their mental illness is a pervasive feature of psychiatric approaches to the care and treatment of ‘the mentally ill’. It would seem that such treatment approaches are coherent only to the degree ‘the mentally ill’ can be considered responsible moral agents. This paper explores these issues with regard to that form of mental illness categorized as the personality disorders. It describes the morally and clinically relevant features of personality disorder, explains how they do not fit traditional analytic paradigms of ‘mental illness’ and elaborates the argument that persons with this category of mental illness are fully moral persons who are rightly subject to praise and blame.  相似文献   
999.
1000.
Purpose: To evaluate a variable frequency regimen with intravitreal bevacizumab for treatment of neovascular age‐related macular degeneration (AMD) in eyes that have not received any previous treatment. Methods: Retrospective review of patients with neovascular AMD who were treated with three consecutive monthly intravitreal injections of bevacizumab (1.25 mg) and retreated based on the PrONTO study criteria. Outcome measures included visual acuity (VA) and central retinal thickness. Subgroup analysis was conducted to identify pretreatment characteristics that could determine visual outcome with treatment. Results: A total of 109 eyes of 109 patients were treated. The mean age was 82 years, and the mean follow‐up period was 9.4 months (range 6–12 months). At baseline, the mean VA was 45.6 letters (6/37.5) and mean central retinal thickness 343 µm. This improved to 51 letters (6/30) (P < 0.001)) and 231 µm (P < 0.001) at 6 months. At 6 months, VA was improved by at least five letters in 50%, remained stable in 30% and worsened by at least five letters in 20% of patients. Patients with large intraretinal cysts on optical coherence tomography before treatment had an increased risk of worse vision (odds ratio 10.5, 95% confidence interval 1.69–64.99; P = 0.018). Conclusions: The majority of patients had improvement or stability of VA regardless of the angiographic type of choroidal neovascularization. Intravitreal bevacizumab with this tailored regimen is beneficial in the treatment of neovascular AMD in the short term. The presence of large intraretinal cysts on optical coherence tomography is a poor prognostic factor for visual improvement with this treatment.  相似文献   
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