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排序方式: 共有1310条查询结果,搜索用时 0 毫秒
1.
We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS.  相似文献   
2.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
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AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated.  相似文献   
5.
Recombination of deltaRec to psiJalpha will delete the TCR delta gene, which is thought to play an important role in the bifurcation of the TCR alphabeta versus TCR gammadelta differentiation lineages. We recently detected a DNA-binding protein in human thymocytes, the so- called PJA-BP, which recognizes the psiJalpha gene segment and might be one of the factors involved in the regulation of preferential deltaRec- psiJalpha rearrangements. We now investigate PJA-BP expression and its correlation with TCR delta gene deletion in thymocytes. Our electrophoretic mobility shift assay experiments showed that the PJA-BP is evolutionary conserved in human, murine and simian thymocytes. Using a large series of human hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is thymocyte specific and seems to be restricted to thymocytes committed to the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte subpopulations showed that preferential deltaRec-psiJalpha rearrangements as well as PJA-BP expression can be detected from the immature CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage onwards. These experiments indicate that expression of PJA-BP in human thymocytes starts simultaneously with preferential deltaRec-psiJalpha rearrangements, which supports our hypothesis that PJA-BP is one of the factors involved in the preferential recombination of deltaRec to psiJalpha.   相似文献   
6.
The present study was designed to ascertain whether the negative effects on reproductive potential of post-ovulatory ageing in vitro of oocytes can be prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were aged in vitro for 12 h prior to insemination in the presence of varying concentrations of L-ascorbic acid, 6-methoxy- 2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta- mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was associated with lower fertilization rate, higher proportion of concepti exhibiting cellular fragmentation at 24 h post-insemination and lower percentage of concepti reaching the blastocyst stage. Ascorbic acid, Trolox and EDTA had no effect on cellular fragmentation or potential of oocytes for development. However, the probability of an oocyte reaching the blastocyst stage was decreased (P < or = or = 0.05) in oocytes incubated in the presence of L-cystine (50 and 500 microM) and beta-mercaptoethanol (5, 50 and 500 microM) when compared to control aged oocytes. Age-associated cellular fragmentation at 24 h post-insemination was partially prevented (P < or = 0.05) by incubating oocytes in the presence of beta-mercaptoethanol (500 microM). DTT (50 and 500 microM) increased (P < or = 0.05) fertilization rate and number of cells at 81 h post-insemination to levels similar to those exhibited by control oocytes. Furthermore, both age-associated fragmentation at 24 h post-insemination (P < or = 0.05) and decreased potential of oocytes for development to the blastocyst stage (P < or = 0.05) were prevented, at least in part, by culturing oocytes in the presence of DTT (50 microM). Although the mechanism by which DTT exerts its beneficial effects on aged oocytes remains to be elucidated, it may protect oocytes by preventing oxidation of free thiol groups and/or altering a redox-independent signalling pathway that mediates cellular fragmentation and death.   相似文献   
7.
In order to gain a better insight into the structure and function of the regulatory domain (RD) of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, 19 RD missense mutations that had been identified in patients were functionally characterized. Nine of these (I601F, L610S, A613T, D614G, I618T, L619S, H620P, G628R and L633P) resulted in aberrant processing. No or a very small number of functional CFTR proteins will therefore appear at the cell membrane in cells expressing these mutants. These mutations were clustered in the N- terminal part of the RD, suggesting that this subdomain has a folding pattern that is very sensitive to amino acid changes. Mutations that caused no aberrant processing were further characterized at the electrophysiological level. First, they were studied at the whole cell level in Xenopus laevis oocytes. Mutants that induced a whole cell current that was significantly different from wild-type CFTR were subsequently analysed at the single channel level in COS1 cells transiently expressing the different mutant and wild-type proteins. Three mutant chloride channels, G622D, R792G and E822K CFTR, were characterized by significantly lower intrinsic chloride channel activities compared with wild-type CFTR. Two mutations, H620Q and A800G, resulted in increased intrinsic chloride transport activities. Finally, T665S and E826K CFTR had single channel properties not significantly different from wild-type CFTR.   相似文献   
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9.
乔振军  黄裕新  王景杰 《医学争鸣》2000,21(10):1233-1233
1 病例报告 女 ,45岁 ,因吞咽困难 16 mo伴发热 15 d,于1999- 0 7- 12入院 .于 16 mo前与人争吵后出现吞咽困难 ,以进食馒头、面条为著 ,剑突下有时出现梗噎感 ,随即呕吐 ,呕出所进食物及粘液 ,情绪波动可诱发症状加重 ,伴食欲减退、返酸 .15 d前无诱因出现不规则发热 ,T38~ 39℃ ,上腹痛加重 ,全身酸困不适 ,乏力、头晕、消瘦 .追问病史 ,患者 5 a前双手、足疼痛麻木 ,尤以受凉、精神刺激后明显 ,手指初发白 ,继而发紫 ,变红 ,且麻木疼痛加重 ,手足小关节渐僵硬、畸形 .曾到多家医院就诊 ,诊断 :“雷诺病、类风湿性关节炎”.2 a前出现…  相似文献   
10.
The target of autoantibodies in Goodpasture's disease, the Goodpastureantigen has recently been characterized as the NC1 domain ofthe 3 chain of type IV collagen. In order to study the Goodpastureantigen in different organs, NC1 domains were isolated frombasement membranes (BM) of human glomeruli (GBM), tubules (TBM),alveoli (ABM), placenta (PBM) and aorta (VBM). NC1 preparationswere separated by 2-D electrophoresis, and silver stained orimmunoblotted to determine the subunit structure and antigenicityof different basement membranes. All basement membranes containedmonomeric components of MW 26 kDa and 24 kDa, and associateddimers, corresponding to the 2-D location of 1(IV) and cc2(IV)chains respectively. However, GBM, ABM, and to a lesser extentTBM possessed an extra set of monomeric components of MW 28kDa and associated dimers corresponding to the proposed locationof 3(IV) and 4(IV) chains. 2-D-separated polypeptides were Westernblotted with autoantibodies from patients with Goodpasture'sdisease, a monoclonal antibody to the Goodpasture antigen (P1)and a monoclonal antibody to the bovine 3(IV) chain. The predominantbinding of all these reagents was to cationic 28 kDa monomersof GBM, ABM and TBM, corresponding to the 3(IV) chain, althoughautoantibodies and P1 also bound to neutral 28 kDa monomers,corresponding to the 4(IV) chain. Autoantibodies bound weaklyto more neutral components of PBM and VBM, but neither monoclonalantibody bound to these basement membranes. This study suggeststhat there are two separate type IV collagen networks: one containingthe l(IV) and 2(IV) chains appears to be present in all basementmembranes, and the other containing the 3(IV) and 4(IV) chainshas a tissue specific distribution. The latter network bearingthe Goodpasture antigen is expressed in the basement membranesof both kidney and lung, the organs involved in Goodpasture'sdisease.  相似文献   
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