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991.
The purpose of the present study is to assess QT-interval measurements from the EASI 12-lead electrocardiogram (ECG) as compared with the standard 12-lead ECG. The QT interval was automatically determined in simultaneously recorded standard and EASI 12-lead ECGs, using a validated wavelet-based delineator. The agreement between the 2 sets of measurements was quantified both on a lead-by-lead basis and a multilead basis with global definitions of QRS onset and T-wave end.The results show that the agreement between QT-interval measurements from the 2 lead systems is acceptable, with negligible mean differences and with correlation coefficients ranging from 0.91 to 0.98 depending on the lead studied. Although the SD shows a clear dependence on the selected lead (ranging from 9.2 to 26.4 milliseconds), differences are within the accepted tolerances for automatic delineation. In a few patients, large differences were found, mainly because of changes in morphology present in both lead systems. QT intervals measured by the multilead approach were considerably more stable than single-lead measurements and resulted in a much better agreement between the 2 lead systems (correlation coefficient, 0.98; QT difference, 1.1 ± 9.8 milliseconds). Thus, the EASI 12-lead ECG may be used for reliable QT monitoring when the multilead delineation approach is adopted.  相似文献   
992.

Objective

This study tests the ability of high-frequency components of the depolarization phase (HF-QRS) vs conventional ST-elevation criteria to detect and quantify myocardial ischemia.

Methods

Twenty-one patients admitted for elective percutaneous coronary intervention were included. Quantification of the ischemia was made by myocardial scintigraphy. High-resolution electrocardiogram before and during percutaneous coronary intervention was recorded and signal averaged. The HF-QRS were determined within the frequency band 150 to 250 Hz. ST-segment deviation was measured in the standard frequency range (<100 Hz).

Results

HF-QRS criteria were met by 76% of the patients, whereas 38% met the ST-elevation criteria (P = .008). Both HF-QRS reduction and ST elevation correlated significantly with the amount of ischemia (HF-QRS: r = 0.59, P = .005 for extent and r = 0.69, P = .001 for severity; ST elevation: r = 0.49, P = .023 for extent and r = 0.57, P = .007 for severity).

Conclusions

This study suggests that HF-QRS analysis could provide valuable information both to detect acute ischemia and to quantify myocardial area at risk.  相似文献   
993.
After myeloablative treatment and allogeneic stem cell transplantation (SCT), patients are kept in isolation rooms in the hospital to prevent neutropenic infections. During a 3-year period, patients were given the option of treatment at home after SCT. Daily visits by an experienced nurse and daily phone calls from a physician from the unit were included in the protocol. We compared 36 patients who wished to be treated at home with 18 patients who chose hospital care (control group 1). A matched control group of 36 patients treated in the hospital served as control group 2. All home care patients had hematologic malignancies and 19 were in first remission or first chronic phase. Of the donors, 25 were unrelated. The patients spent a median of 16 days at home (range, 0-26 days). Before discharge to the outpatient clinic after SCT, patients spent a median of 4 days (range, 0-39 days) in the hospital. In the multivariate analysis, the home care patients were discharged earlier (relative risk [RR] 0.33, P =.03), had fewer days on total parenteral nutrition (RR 0.24, P <.01), less acute graft-versus-host disease (GVHD) grades II-IV (RR 0.25, P =.01), lower transplantation-related mortality rates (RR 0.22, P =.04), and lower costs (RR 0.37, P <.05), compared with the controls treated in the hospital. The 2-year survival rates were 70% in the home care group versus 51% and 57% (not significant) in the 2 control groups, respectively (P <.03). To conclude, home care after SCT is a novel and safe approach. This study found it to be advantageous, compared with hospital care.  相似文献   
994.
The role of ursodeoxycholic acid (UDCA) in the prevention of hepatic complications after allogeneic stem cell transplantation was studied in a prospective randomized open-label multicenter trial. A total of 242 patients were allocated to receive (n = 123) or not to receive (n = 119) UDCA in the dose of 12 mg/kg/d orally from the day preceding the conditioning until day 90 after transplantation. In the UDCA-treated group a significantly smaller proportion of patients developed a serum bilirubin level exceeding 50 microM (18 of 123 versus 31 of 119, P =.04), and similarly a smaller proportion of patients exceeded the alanine aminotransferase level of 100 U/L. There was no difference in the incidence of veno-occlusive disease of the liver. Compared to the control group, in the UDCA-treated group there was a nonsignificant trend toward a lower overall incidence of acute graft-versus-host disease (GVHD) and a significantly lower incidence of grade III to IV acute GVHD (5 of 123 versus 17 of 119, P =.01), stage II to IV liver and intestinal GVHD, and stage III to IV skin GVHD. There was no difference in the incidence of chronic GVHD or in the relapse rate. Among the patients given UDCA, the survival at 1 year was significantly better, 71% versus 55% (P =.02), and the nonrelapse mortality rate was lower, 19% versus 34% (P =.01), than in the control group. There were significantly more deaths in GVHD in the control group. In conclusion, UDCA administration reduced hepatic problems and severe acute GVHD and improved survival. These results suggest a role for UDCA in the prevention of transplant-related complications in allogeneic transplantation.  相似文献   
995.
We examined the relationship between estrogen and pain in women undergoing in vitro fertilization (IVF). Quantitative sensory tests (QST) were performed twice during the IVF-regimen: once during hormonal down-regulation and once during hormonal up-regulation. A group of healthy men and a group of women using monophasic contraceptives were also examined, to control for session-to-session effects. Among the women undergoing IVF, serum 17β-estradiol levels differed strongly between treatments as expected, and increased from 65.7 (SD = 26) pmol/L during the down-regulation phase, to 5,188 (SD = 2,524) pmol/L during the up-regulation phase. Significant outcomes in the QST were only seen for temperature perception thresholds (1.7 °C versus 2.2 °C; P = .003) and cold pain threshold (11.5 °C versus 14.5 °C; P = .04). A similar change in cold pain threshold was also seen in the 2 control groups, however, and statistical analysis suggested that this change was due to a session-to-session effect rather than being the result of hormonal modulation. Heat pain thresholds, heat tolerance, pressure pain thresholds, and the cold pressor test showed no significant differences between sessions. These data demonstrate that pain perception and pain thresholds in healthy women show little, if any, changes even with major variations in serum estradiol levels. PERSPECTIVE: This study shows that pain perception and tolerance in women undergoing in vitro fertilization do not vary, despite the dramatic changes in 17β-estradiol levels induced by the treatment regimen. The result thus suggests that in humans, contrary to experimental animals, changes in estrogen levels have little influence on pain sensitivity.  相似文献   
996.
The objective of this study was to investigate the preventive effect of oral hygiene on pneumonia and respiratory tract infection, focusing on elderly people in hospitals and nursing homes, by systematically reviewing effect estimates and methodological quality of randomized controlled trials (RCTs) and to provide an overview of additional clinical studies in this area. Literature searches were conducted in the Medline database, the Cochrane library databases, and by hand-searching reference lists. Included publications were analyzed for intervention (or topic) studied, main conclusions, strength of evidence, and study design. RCTs were further analyzed for effect magnitudes and methodological details. Absolute risk reductions (ARRs) and numbers needed to treat (NNTs) were calculated. Fifteen publications fulfilled the inclusion criteria. There was a wide variation in the design and quality of the studies included. The RCTs revealed positive preventive effects of oral hygiene on pneumonia and respiratory tract infection in hospitalized elderly people and elderly nursing home residents, with ARRs from 6.6% to 11.7% and NNTs from 8.6 to 15.3 individuals. The non-RCT studies contributed to inconclusive evidence on the association and correlation between oral hygiene and pneumonia or respiratory tract infection in elderly people. Mechanical oral hygiene has a preventive effect on mortality from pneumonia, and non-fatal pneumonia in hospitalized elderly people and elderly nursing home residents. Approximately one in 10 cases of death from pneumonia in elderly nursing home residents may be prevented by improving oral hygiene. Future research in this area should be focused on high-quality RCTs with appropriate sample size calculations.  相似文献   
997.
We prospectively studied early hepatitis C virus kinetics and sustained virological response rates in HIV/HCV coinfected (n = 13) and HCV monoinfected matched controls (n = 26) with HCV genotype 2/3 treated with pegylated interferon (peg-IFN) alpha-2a 135 microg/week plus ribavirin 11 mg/kg daily during 24 weeks. No significant difference in HCV-RNA decay was seen at any time point during the initial 12 weeks of therapy. Sustained virological response was achieved in 9/13 (69%) versus 20/26 (77%) patients (intent-to-treat), respectively. The lower-than-standard peg-IFN dose offered high compliance and reasonable sustained virological response rates.  相似文献   
998.
Neutralizing autoantibodies to type I, but not type II, interferons (IFNs) are found at high titers in almost every patient with autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), a disease caused by AIRE gene mutations that lead to defects in thymic T-cell selection. Combining genome-wide expression array with real time RT-PCR assays, we here demonstrate that antibodies against IFN-alpha cause highly significant down-regulation of interferon-stimulated gene expression in cells from APECED patients' blood by blocking their highly dilute endogenous IFNs. This down-regulation was lost progressively as these APECED cells matured in cultures without neutralizing autoantibodies. Most interestingly, a rare APECED patient with autoantibodies to IFN-omega but not IFN-alpha showed a marked increase in expression of the same interferon-stimulated genes. We also report unexpected increases in serum CXCL10 levels in APECED. Our results argue that the breakdown of tolerance to IFNs in AIRE deficiency is associated with impaired responses to them in thymus, and highlight APECED as another autoimmune disease with associated dysregulation of IFN activity.  相似文献   
999.
Gonadotropins and testosterone are important regulators of spermatogenesis, even though gonadotropin receptors and the androgen receptor are not expressed by germ cells. However, a functional role for estrogens in connection with male reproduction has been postulated on the basis of the phenotypes of mice lacking estrogen receptor (ER) and cytochrome P-450 aromatase. This has further support by findings of ER expression in the testis, including that of ERbeta in spermatogonia. 5alpha-Androstane-3beta, 17beta-diol (3betaAdiol), a metabolite of testosterone produced via the intermediate potent androgen 5alpha-dihydrotestosterone (DHT), has been reported to selectively bind ERbeta rather than EpsilonRalpha, but not androgen receptor. Here, we have characterized the influence of 17beta-estradiol (E), the major physiological estrogen, 3betaAdiol, and DHT on DNA synthesis in vitro by segments of the seminiferous epithelium at different stages of the seminiferous epithelial cycle in the rat. E and 3betaAdiol exerted similar stimulatory effects on premitotic DNA synthesis in stage I segments, whereas other stages tested (V, VIIa, and XIII-IX) remained unresponsive. In contrast, DHT had no effect on this process. 5-bromo-2'-deoxyuridine labeling of stage I segments revealed a 30-fold higher labeling index in the presence than in the absence of E, and the labeled cells were identified as spermatogonia. Moreover, high levels of 3betaAdiol were found in the testis of intact rats as well as in primary cultures of rat Leydig cells in response to human chorionic gonadotropin. We suggest that 3betaAdiol may serve as a growth factor for germ cells stimulating premitotic DNA synthesis in connection with spermatogenesis via an ERbeta-dependent pathway.  相似文献   
1000.
Mycobacterium avium is the most common pathogen in children presenting as non-tuberculous mycobacterial lymphadenitis. In Sweden non-tuberculous mycobacterial infection is a notifiable disease. The goal of our study was to determine the annual incidence of M. avium infection in Swedish children, 1998-2003, and describe clinical features related to age and treatment of children with M. avium lymphadenitis. To do this, we retrospectively analysed patient records of 162 children less than 7 y of age from the entire country with culture-verified M. avium disease. The incidence of M. avium infection in Sweden was lower in 2000-2003 than in 1998-1999. Young children (相似文献   
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