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101.
Background: Coronary angioplasty, although of proven use in partial occlusion, has not been shown to be of similar benefit in chronic total occlusion. Aims: To assess the utility of coronary angioplasty in chronically totally occluded vessels in patients undergoing angioplasty and to determine the success of TIMI-I flow before angioplasty compared to those patients with TIMI-O flow. Methods: A group of 178 consecutive patients (from 1984 to 1992), who underwent angioplasty of a chronic occlusion, were analysed. There were 136 males and 42 females with a mean age of 56.9 years. Results: Initial technical success was achieved in 65%. Patients with TIMI-I flow before angioplasty had a higher chance of success (700%) compared to those with TIMI-O flow (53%), p < 0.04. During hospitalisation six patients suffered myocardial infarction (MI), two required surgery and one patient died. During a mean follow-up of 2.8 years the overall survival rate was 95% for the group as a whole. Freedom from coronary surgery was significantly greater in patients with successful angioplasty (93%) than those without (66%, p < 0.002). The above two populations also showed a significant difference in the incidence of angina (35%vs 56%, p < 0.0003). However, the incidence of MI (6%vs 5%, p > O.5) and cardiac survival (98%vs 94%, p > 0.l) did not differ significantly in the two groups. Restenosis occurred in 63% of the 95 patients (82%) who returned for follow-up angiography. Eighteen of the 59 patients (28%) with restenosis had a reocclusion. Conclusion: The success rate for angioplasty of chronic total occlusions is acceptable. Long-term clinical benefit in patients with successful angioplasty is suggested by the high freedom from angina and the lesser need for coronary surgery. No major impact on either the incidence of MI or cardiac survival was noted when patients who had coronary surgery were included, although it must be emphasised that the sample size in this study was insufficient to detect a difference in these outcome variables.  相似文献   
102.
103.
BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) from human leukocyte antigen (HLA)-compatible sibling donors is a potential curative treatment for hematological and non-hematological malignancies. Nevertheless, high mortality rates may be associated with this therapy, especially in older patients, those with other comorbidities or who receive a second HSCT. PATIENTS AND METHODS: We analyzed the factors associated with transplant-related mortality (TRM) and overall survival in 157 consecutive adult patients (104 males and 53 females) who received a HSCT [29 bone marrow (BM) transplantation and 128 peripheral blood (PB) transplantation] from a HLA-identical sibling between January 1995 and March 2002 in our institution. One hundred patients received a standard conditioning prior to HSCT (STAND) and 57 patients received a reduced-intensity conditioning (RIC) HSCT. Fifty-eight patients were in an early phase at transplant and 99 in a non-early phase. Median age was 46 yr (16-66), and 90 patients (57%) were >45 yr of age. RESULTS: Patients in the RIC group were older than those in the STAND group, and had a higher proportion of non-early disease phases including a prior autologous HSCT in 39%. Median follow-up for survivors was 28 and 15 months in the STAND and RIC groups (P < 0,001), respectively. Cumulative incidence of TRM at 2 yr was 30% [95% confidence interval (CI) 22-41%] for the STAND group and 22% (95% CI 13-37%) for the RIC group [non-significant (NS)]. Factors associated with a higher TRM in multivariate analysis were: STAND vs. RIC conditioning regimen [relative risk (RR) 5.4; 95% CI 2.3-12.8; P < 0.001]; age > or =45 yr vs. <45 yr (RR 5; 95% CI 2.4-10.8, P < 0.001); second vs. first HSCT (RR 2.8, 95% CI 1.3-6.3, P = 0.01) and non-T-cell-depleted vs. T-cell-depleted graft (RR 2.7, 95% CI 1.3-5.8, P = 0.009). Overall survival (OS) at 2 yr was 52.5 +/- 10.4% for STAND group and 59 +/- 16.8% in RIC group. Factors associated with poorer OS in multivariate analysis were: STAND vs. RIC conditioning regimen (RR 3.4, 95% CI 1.7-6.9, P = 0.001); age > or =45 vs <45 yr (RR 2.5, 95% CI 1.4-4.5, P = 0.002) and diagnosis [other than chronic myeloid leukemia (CML) vs. CML] (RR 2.6, 95% CI 1.2-5.7 P = 0.02). CONCLUSIONS: Our results indicate that the introduction of RIC allogeneic HSCT for patients at high risk for TRM (advanced age, prior HSCT and non-T-cell depletion) leads to a reduction in the TRM and improvement in the OS.  相似文献   
104.
105.
Immunoglobulin (Ig) gene expression has been followed during the later stages of development of the murine fetal liver. Biosynthetic labeling and immunoprecipitation were used to isolate Ig-related polypeptides from fetal and neonatal livers. By examination of the specific immune precipitates, the earliest detectable Ig was shown to consist only of mu heavy chain. At about the time of birth, when light chain synthesis became evident, separation of surface Ig-positive cells from surface Ig-negative cells by using anti-Ig-coated dishes showed that cells lacking surface Ig (pre-B lymphocytes) synthesized only mu chains. Thus, commencement of light chain synthesis was closely coordinated with the appearance of surface Ig. Ig RNA species were examined by electrophoretic fractionation and hybridization with cloned Ig DNA sequences. The sizes and amounts of Ig mRNA were found to correlate with the pattern of mu and light chain protein biosynthesis. mu chain RNA species appeared earlier in gestation than light chain RNA did, and only after birth did light chain sequences reach levels equivalent to those of mu chain. Cell populations enriched in pre-B lymphocytes also contained an excess of mu over light chain mRNA.  相似文献   
106.
Allogeneic stem cell transplantation (allo-SCT) after a reduced-intensity conditioning (RIC) protocol is associated with decreased short-term toxicity. This suggests that the procedure could be performed on an outpatient basis. We analysed the incidence and risk factors of grade >or=2 conditioning-related toxicities (CRTs) as a hallmark for hospital admission, in 41 consecutive patients allografted from an HLA identical sibling after RIC. The RIC regimen consisted of fludarabine plus melphalan for lymphoid malignancies, and fludarabine plus busulphan for myeloid malignancies. In all, 11 patients (27%) did not experience any toxicity. The more frequent CRTs observed were neutropenic fever and gastrointestinal toxicity. The median duration of hospitalisation was 27 (range, 17-50) days. If allo-SCT had been planned as an outpatient procedure and admission indicated only in the case of >or=2 CRTs, the inpatient period would have decreased to 9 (range, 0-33) days (P<0.001). No risk factors for CRTs were identified. Allo-SCT after an RIC regimen is a well-tolerated procedure. Our results warrant a prospective pilot trial of nonmyeloablative allo-SCT performed in the outpatient setting.  相似文献   
107.
The advent of whole‐exome next‐generation sequencing (WES) has been pivotal for the molecular characterization of Mendelian disease; however, the clinical applicability of WES has remained relatively unexplored. We describe our exploration of WES as a diagnostic tool in a 3½‐year old female patient with a 2‐year history of episodic muscle weakness and paroxysmal dystonia who presented following a previous extensive but unrevealing diagnostic work‐up. WES was performed on the proband and her two parents. Parental exome data was used to filter potential de novo genomic events in the proband and suspected variants were confirmed using di‐deoxy sequencing. WES revealed a de novo non‐synonymous mutation in exon 21 of the calcium channel gene CACNA1S that has been previously reported in a single patient as a rare cause of atypical hypokalemic periodic paralysis. This was unexpected, as the proband's original differential diagnosis had included hypokalemic periodic paralysis, but clinical and laboratory features were equivocal, and standard clinical molecular testing for hypokalemic periodic paralysis and related disorders was negative. This report highlights the potential diagnostic utility of WES in clinical practice, with implications for the approach to similar diagnostic dilemmas in the future.  相似文献   
108.
Previously, we demonstrated that autoantibodies (AAb) in multiple sclerosis (MS) reveal site-specific binding and cleavage toward myelin basic protein (MBP) epitope library. We have found several fragments of MBP immunodominant in terms of AAb binding. Here, we applied these peptides to DA rats with induced protracted relapsing experimental allergic encephalomyelitis (EAE) most closely related to MS. DA rats with EAE induced by syngenic spinal cord homogenate in complete Freund's adjuvant were treated by nasal route with human MBP 46–62, 81–102, 124–139, 147–170, and Copaxone®. MBP 124–139 and 147–170 displayed only mild therapeutic effects but MBP 46–62 significantly reduced EAE, reflected by lower clinical scores and shorter EAE duration compared to controls.  相似文献   
109.
Motor incoordination, immune deficiencies, and an increased risk of cancer are the characteristic features of the hereditary disease ataxia-telangiectasia (A-T), which is caused by mutations in the ATM gene. Through gene targeting, we have generated a line of Atm mutant mice, Atm(y/y) mice. In contrast to other Atm mutant mice, Atm(y/y) mice show a lower incidence of thymic lymphoma and survive beyond a few months of age. Atm(y/y) mice exhibit deficits in motor learning indicative of cerebellar dysfunction. Even though we found no gross cerebellar degeneration in older Atm(y/y) animals, ectopic and abnormally differentiated Purkinje cells were apparent in mutant mice of all ages. These findings establish that some neuropathological abnormalities seen in A-T patients also are present in Atm mutant mice. In addition, we report a previously unrecognized effect of Atm deficiency on development or maintenance of CD4(+)8(+) thymocytes. We discuss these findings in the context of the hypothesis that abnormal development of Purkinje cells and lymphocytes contributes to the pathogenesis of A-T.  相似文献   
110.

Objectives

The aim of the study was to evaluate the long‐term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)‐, darunavir/ritonavir (DRV/r)‐, and lopinavir/ritonavir (LPV/r)‐containing regimens.

Methods

Data were analysed for 5678 EuroSIDA‐enrolled patients starting a DRV/r‐, ATZ/r‐ or LPV/r‐containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART‐naïve subjects (8%) at ritonavir‐boosted protease inhibitor (PI/r) initiation; (2) ART‐experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV‐1 RNA copies/mL; and (3) ART‐experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan–Meier and multivariable Cox models were used to compare risks of failure by PI/r‐based regimen. The main analysis was performed with intention‐to‐treat (ITT) ignoring treatment switches.

Results

The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log‐rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART‐naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment‐experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r‐based ART.

Conclusions

Although confounding by indication and calendar year cannot be completely ruled out, in ART‐experienced subjects the long‐term effectiveness of DRV/r‐containing regimens appears to be greater than that of ATZ/r and LPV/r.
  相似文献   
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