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1.
Exhaled breath condensate (EBC) provides a noninvasive means of sampling the lower respiratory tract. Collection of EBC might be useful in the assessment of airway oxidative stress in smokers. The aim of this study was to determine 8-isoprostane and hydrogen peroxide levels in EBC, and, in addition, to investigate the reproducibility of these measurements. EBC samples were collected from 12 healthy male smokers at three time points within 1 week. 8-isoprostane and H2O2 were measured in nonconcentrated EBC using immunochemical and colorimetric assays, respectively. 8-isoprostane and H2O2 were detected in only 36 and 47% of all EBC samples, respectively. It was not possible to calculate the within-subject variation in a reliable manner since only three of the 12 smokers exhibited detectable 8-isoprostane concentrations on all three occasions (mean 4.6 pg x mL(-1); range 3.9-7.7 pg x mL(-1)), whereas H2O2 could not be detected on all three occasions in any of the smokers. Spiking experiments revealed a recovery of 83.5-109.5% for 8-isoprostane and 69.9-129.0%, for H2O2 in fresh EBC samples. It was concluded that levels of 8-isoprostane and hydrogen peroxide cannot be reproducibly assessed in exhaled breath condensate from healthy smokers because of their low concentration and/or the lack of sensitivity of the available assays.  相似文献   
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Sequential contrast-enhanced MR imaging of the penis   总被引:1,自引:0,他引:1  
Kaneko  K; De Mouy  EH; Lee  BE 《Radiology》1994,191(1):75
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BACKGROUND: Functional status is considered an important measure of health status in primary care. The COOP-WONCA charts, which comprise six single-item scales, have mainly been used to determine functional ability in chronically ill patients. AIM: A study was carried out to determine whether the charts are able to measure the degree of functional impairment associated with acute illness and the improvement in functional ability accompanying the process of recovery. METHOD: A total of 95 patients presenting with acute low back pain were recruited from 15 single-handed general practices in northern Germany. At presentation and at two-week follow up, these patients completed self-administered questionnaires which included the COOP-WONCA charts. The charts ask patients to use the timescale of the past two weeks when rating their condition. Baseline and follow-up measurements of the charts were compared and correlations of chart scores with patients' measurements of pain intensity on a visual analogue scale, general practitioners' ratings of impairment and patients' measurements of recovery were analysed. RESULTS: Only the chart measuring change in health revealed a deterioration in functional ability associated with the onset of pain and an improvement in functional status at follow up. Two of the other charts indicated a deterioration at follow up. Only the chart measuring change in health was correlated with ratings of pain and impairment at baseline. At follow up, strong correlations were found between general practitioners' assessments of impairment, patients' ratings of pain and patients' ratings of recovery for all scales except for those measuring social activities and daily activities. The patients interpreted the instructions for using the COOP-WONCA charts differently; some included the period of acute back pain while others did not. CONCLUSION: Of the six charts only the change in health chart proved to be a suitable scale for measuring short-term changes in functional ability among general practice patients with acute low back pain. This may partly be a result of patients misunderstanding the instructions. If the COOP-WONCA charts are used with acutely ill patients, the fixed two-weeks timescale is not appropriate. It is suggested that patients consider their present complaints when rating their condition.  相似文献   
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Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result.   相似文献   
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We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells.  相似文献   
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目的 探讨盐酸喹那普利 (QuinaprilHydrochloride)治疗轻、中度原发性高血压的有效性和安全性。方法 全国 6家医院参加的一项多中心、随机、双盲、平行组间对照研究。结果  113例原发性高血压病人治疗 8周后 ,总有效率达 85 84% ,统计学有显著性差异。盐酸喹那普利副反应较轻 ,对肾脏、肝脏、造血系统和心脏未见有害作用。结论 盐酸喹那普利是一种安全、疗效好、副反应小的治疗轻、中度原发性高血压的有效药物。  相似文献   
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Blood isotone contrast media is considered to be less toxic to vascular and pancreatic duct endothelium than high-osmolar contrast media. In this study we assessed the impact of a low-osmolar contrast agent compared with a blood isotone product on pancreatic damage induced by endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic retrograde sphincterotomy (EST). In a prospective trial 42 consecutive ERCP/EST patients were randomized to receive either iopromid, a low-osmolar non-ionic contrast agent (770 mosmol/kg H2O), or iotrolan, a blood-isotone non-ionic product (320 mosmol/kg H2O). The endoscopies were performed by two experienced endoscopists. Forty patients were included in the study. Blood samples were collected before and 40 min, 2, 4, 6 and 24 h after the endoscopic procedure. Samples were analysed for pancreatic serum enzymes, acute-phase proteins and blood counts. A clinical pain score was investigated. Post-ERCP pancreatitis was diagnosed in 2 patients in the iopromid group and in 5 patients in the iotrolan group. There was no significant difference between groups in the time course of pancreatic serum enzymes, acute-phase proteins or in the pain score. Due to the small number of patients in this study, only stronger differences caused by the two contrast media could have led to statistically significant results. We did not observe statistically significant differences in comparing iotrolan and iopromid concerning ERCP/EST-induced pancreatic damage. Received: 26 February 1999; Revised: 14 May 1999; Accepted: 9 June 1999  相似文献   
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