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991.
OBJECTIVES: This study sought to assess outcomes of men with double-vessel coronary artery disease randomly assigned to treatment by percutaneous transluminal coronary angioplasty (PTCA) or medical therapy, compared with previously reported outcomes for men with single-vessel disease. BACKGROUND: We previously reported that PTCA provides better symptom relief and treadmill performance than medical therapy for men with stable angina pectoris due to single-vessel disease. Whether this advantage applies to patients with double-vessel disease is unknown. METHODS: Male patients (n = 328) with stable angina pectoris and ischemia on treadmill testing were randomly assigned to PTCA or medical therapy; 101 patients had double-vessel disease, and 227 had single-vessel disease. Symptoms, treadmill performance, quality of life score, coronary stenosis and myocardial perfusion were compared at baseline and at 6 months. Patients were followed up for up to 6 years and underwent additional treadmill testing 2 to 3 years after randomization. RESULTS: PTCA-treated and medically treated patients with double-vessel disease experienced comparable improvement in exercise duration (+1.2 vs. +1.3 min, respectively, p = 0.89), freedom from angina (53% and 36%, respectively, p = 0.09) and improvement of overall quality of life score (+1.3 vs. +4.4, respectively, p = 0.32) at 6 months compared with baseline. This contrasts with greater advantages favoring PTCA by these criteria in patients with single-vessel disease (p = 0.0001 to 0.02). Trends present at 6 months persisted at late follow-up. Patients undergoing double-vessel dilation had less complete initial revascularization (45% vs. 83%) and greater average stenosis of worst lesions at 6 months (74% vs. 56%). Likewise, patients with double-vessel disease showed less improved myocardial perfusion imaging (59% vs. 75%). CONCLUSIONS: PTCA is beneficial in male patients with double-vessel disease; however, we cannot demonstrate the same advantage over medical therapy seen in similar patients with single-vessel disease. Less complete revascularization and greater restenosis for patients having multiple dilations would account for these findings. Alternatively, a type 2 error might be operative. Technical advances since completion of this trial might improve these outcomes. These findings warrant further investigation in a larger trial.  相似文献   
992.
AIM: To confirm clonal nature of idiopathic hypereosinophilic syndrome (IHES), its relevance to Ph'-positive chronic myeloid leukemia. MATERIALS AND METHODS: 3 cases of idiopathic hypereosinophilic syndrome are reported with morphologic analysis of bone marrow cells and cytogenetic examinations. In one patient the presence of Ph'-chromosome was confirmed at fluorescent in situ hybridization (FISH) and molecular-genetic analysis (bcr/abl). Samples of bone marrow, spleen and liver were examined pathohistologically. RESULTS: The presence of chromosome anomaly t(9;22), i.e. Ph'-chromosome, associated with chronic myeloid leukemia (CML) was identified in all the 3 cases. There was also myeloid hyperplasia in the bone marrow (with primarily mature, eosinophilic granulocytes), spleen and liver, depression of megakaryocyto- and erythropoiesis. 2 patients had similar clinical symptoms which was not typical for CML in chronic phase: fever, elevated ESR, clear-cut anemia and thrombocytopenia. In the absence of hyperleukocytosis, blood and bone marrow eosinophils remained high (42.5, 21.5, 42.5% and 21.4, 7.1, 6.5%, respectively) due to "mature" forms. The number of blasts in the bone marrow was maximum 2.4%. CONCLUSION: The literature and the obtained data suggest closeness of idiopathic hypereosinophilic syndrome and Ph'-positive CML within myeloproliferative diseases.  相似文献   
993.
Induction of cytotoxic T lymphocytes (CTLs) by vaccination has been shown to protect against bacterial, viral, and tumoral challenge. The aim of this study was to identify CTL epitopes on the 38-kDa lipoglycoprotein from Mycobacterium tuberculosis. The identification of these CTL epitopes was based on synthesizing peptides designed from the 38-kDa lipoglycoprotein, with known major histocompatibility complex class I (MHC-I) binding motifs (H-2Db), and studying their ability to up-regulate and stabilize MHC-I molecules on the mouse lymphoma cell line RMA-S. To improve the capacity of the identified peptides to induce CTL responses in mice, palmitic acid with a cysteine-serine-serine spacer amino acid sequence was attached to the amino terminus of the peptide. Two of five peptides with H-2Db binding motifs and their corresponding lipopeptides up-regulated and stabilized the H-2Db molecules on RMA-S cells. Both lipopeptides, in combination with incomplete Freund's adjuvant, induced CTL responses in C57BL/6 (H-2(b)) mice. Moreover, the lipopeptide induced stronger CTL responses than the peptide. The capacity of the various lipopeptides to induce CTL displayed a good relationship with the ability of the (lipo)peptide to up-regulate and to stabilize H-2Db molecules. The capacity of the peptides and lipopeptides to up-regulate and stabilize MHC-I expression can therefore be used to predict their potential to function as a CTL epitope. The newly identified CTL epitopes and their lipid derivatives provide us with important information for future M. tuberculosis vaccine design.  相似文献   
994.
PURPOSE: The accuracy of sonourethrography for the evaluation of bulbar urethral strictures has been well documented. Thus, we sought to define the role of preoperative sonourethrography in establishing objective criteria for procedure selection during bulbar urethral reconstruction. MATERIALS AND METHODS: Sonourethrography was performed preoperatively, just before incision, in 67 men selected for bulbar urethroplasty. All patients had strictures 25 mm. or less in length on preoperative radiographic retrograde urethrography, thus potentially amenable to resection and end-to-end anastomosis. Ultrasonic measurements were prospectively recorded, compared with those on preoperative retrograde urethrography, and used to guide the selection of urethroplasty technique. RESULTS: Overall, a significant trend for retrograde urethrography to underestimate stricture length was demonstrated (r = 0.678, p < 0.0001). Indeed, sonographic measurements were frequently twice those of retrograde urethrography, occasionally more. All 26 patients with short strictures on retrograde urethrography (10 mm. or less) were successfully treated by resection and end-to-end anastomosis, and sonographic assessment did not alter management. However, ultrasonic measurement changed the reconstructive procedure selected in 15 of 41 patients (37%, 3 penile flaps, 12 graft procedures) with bulbar strictures of intermediate length on retrograde urethrography (11 to 25 mm.). CONCLUSIONS: Sonourethrography has a major influence on selection of therapy in patients with bulbar strictures of intermediate length. By prospectively identifying strictures too long for resection and end-to-end anastomosis, sonourethrography enables quantitative criteria for selection of patients who may be more appropriately treated by flap or graft procedures. We advocate excisional therapy for strictures appearing sonographically to be 25 mm. or less, and substitution urethroplasty for longer strictures.  相似文献   
995.
The present study addresses the effect of cochlear implantation on vowel production of 20 post-lingually deafened Dutch subjects. All subjects received the Nucleus 22 implant (3 WSP and 17 MSP processors). Speech recordings were made pre-implantation and three and twelve months post-implantation with the implant switched on and off. The first and second formant frequencies were measured for eleven Dutch vowels (monophthongs only) in an h-vowel-t context. Twelve months post-implantation, the results showed an increase in the ranges of the first and second formant frequency covered by the respective vowels when the implant was switched on. The increase in the formant frequency range was most marked for some subjects with a relatively small formant range pre-implantation. Also, at 12 months post-implantation with the implant switched on we found a significant shift of the first and second formant frequency towards the normative values. Moreover, at this time the results showed significantly increased clustering of the respective vowels, suggesting an improvement in the ability to produce phonological contrasts between vowels. Clustering is defined as the ratio of the between-vowel variance of the first and second formant frequency and the within-vowel variance of three tokens of the same vowel.  相似文献   
996.
The total number of microsatellite loci is considered to be at least 10-fold lower in avian species than in mammalian species. Therefore, efficient large-scale cloning of chicken microsatellites, as required for the construction of a high-resolution linkage map, is facilitated by the construction of libraries using an enrichment strategy. In this study, a plasmid library enriched for tandem repeats was constructed from chicken genomic DNA by hybridization selection. Using this technique the proportion of recombinant clones that cross-hybridized to probes containing simple tandem repeats was raised to 16%, compared with < 0.1% in a non-enriched library. Primers were designed from 121 different sequences. Polymerase chain reaction (PCR) analysis of two chicken reference pedigrees enabled 72 loci to be localized within the collaborative chicken genetic map, and at least 30 of the remaining loci have been shown to be informative in these or other crosses.  相似文献   
997.
Phenotypic and functional properties of gammadelta T cells, which play an important role in mucocutaneous immunity, were examined to elucidate whether immunological abnormality in Behcet's disease may be related to a specific T cell population. We found that CD45RA+ Vgamma9+ Vdelta2+ gammadelta T cells, which constitute a minor population of gammadelta T cells in healthy individuals, were increased in number in Beh?et's disease irrespective of disease activity. This CD45RA+ subset of gammadelta T cells in the active, but not inactive, phase of this disease expressed IL-2Rbeta and HLA-DR, suggesting that they are activated in vivo in active Beh?et's disease. In addition, the CD45RA+ gammadelta T cells produced extreme amounts of tumour necrosis factor and contained perforin granules. These data indicate that a phenotypically distinct subset of gammadelta T cells, CD45RA+ CD45RO- Vgamma9+ Vdelta2+, may contribute to immunological abnormalities which may lead to complexity of pathophysiology in Beh?et's disease.  相似文献   
998.
A specific mutation termed FH-North Karelia [FH-NK] accounts for almost 90% of familial hypercholesterolemia [FH] cases in the Finnish North Karelia, with a population of about 180,000. Extensive search for its presence in the entire North Karelia province revealed 340 carriers of this mutation. Other mutations of the LDL receptor [LDLR] gene accounted for 67 cases of heterozygous FH. This gives a minimum FH prevalence of 1 in 441 inhabitants in North Karelia, with the highest density of patients in the Polvij?rvi commune (1 in 143 inhabitants). Old parish records, confirmation records, and tax records were used to track a common ancestor for most of the present-day North Karelian FH-NK patients in the village of Puso, located within an area where the FH prevalence today is the highest. DNA analysis indicated that 2% of the subjects aged 1 to 25 years would have been diagnosed as false-negative and 7% as false-positive FH patients on the basis of LDL cholesterol [LDL-C] determinations alone. Common genetic variations of apolipoprotein E [apoE], XbaI, polymorphism of apolipoprotein B [apoB], and PvuII polymorphism of the intact LDLR allele contributed little to serum lipid variation in established carriers of the FH-NK allele, although apoE2/4 genotype and the presence of the PvuII restriction site tended to be associated with relatively low LDL-C levels. Coronary heart disease (CHD) was present in 65 (30%) out of the 179 FH gene carriers aged > or = 25 years, and 19 individuals had a previous history of acute myocardial infarction (AMI). The average age (mean +/- SD) at onset of CHD was 42 +/- 7 years for males and 48 +/- 11 years for females (P < .05). In stepwise logistic regression analysis carried out in carriers of the FH-NK allele, age, gender, smoking, and apoE allele E2 all emerged as independent determinants of risk of CHD or AMI. It may be concluded that the relatively high prevalence of FH patients in North Karelia province provides a unique founder population in which genetic and nongenetic factors modifying the course of FH can be effectively investigated.  相似文献   
999.
1000.
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