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991.
We intended to establish a pharmacologic concept of synergistic antiproliferative effects on smooth muscle cells (SMC) by using paclitaxel and cyclosporine A at clinically applicable doses. Coronary SMC were incubated with paclitaxel and cyclosporine A at concentrations of 10 – 20 nmol/L and 83 – 415 nmol/L, respectively. Antiproliferative effects were assessed by cell counts, [3H]thymidine incorporation and cell cycle analysis. In addition, apoptosis was studied by cytoplasmic histone-associated DNA fragments and in vitro protein kinase C activity (PKC) was determined by immunoassay. We found paclitaxel and cyclosporine A to exert a highly supra-additive antiproliferative effect on SMC with significant reductions of cell counts (p < 0.01) and [3H]thymidine incorporation (p < 0.05). SMC were found to be arrested at the G2/M transition. This antiproliferative effect was observed in the absence of DNA fragmentation above values obtained for single compound treatment, which had virtually no impact on cell proliferation. DNA fragmentation started to increase at a drug combination comprising paclitaxel at the higher dose of 20 nmol/L. Under the treatment with both paclitaxel and cyclosporine A, PKC activity showed a 1.8-fold increase (p < 0.05) compared with untreated controls. In conclusion, PKC mediates supra-additive antiproliferative effects of paclitaxel and cyclosporine A on SMC. The data demonstrate a highly efficient pharmacologic concept for the inhibition of SMC proliferation. Further studies are needed to test this concept under in vivo conditions for the prevention of restenosis or transplant vasculopathy by systemic application of cyclosporine A – when already applied for immunosuppressive purposes – and local delivery of paclitaxel. Received: 28 August 2001, Returned for revision: 25 September 2001, Revision received: 20 November 2001, Accepted: 4 December 2001  相似文献   
992.
Cystic fibrosis (CF) is the most common lethal genetic disease affecting 1 in 2500 white patients. Chronic obstructive lung disease and pancreatic insufficiency are the main clinical manifestations of CF. Lung transplantation has become a treatment option for advanced pulmonary disease during the last decade. On the other hand, there is evidence from large cohort studies that CF and immunosuppression are risk factors for pancreatic cancer. Here, we report the case of an 18-year-old female patient with CF and bilateral lung transplantation who underwent Whipple procedure for pancreatic adenocarcinoma at the age of 12 years. Because of growth retardation, the patient underwent a 2-year period of growth hormone treatment before the diagnosis of pancreatic cancer. This case should sensitize physicians to be aware of the increased risk for pancreatic cancer in CF patients especially in those after lung transplantation with immunosuppression and prolonged survival.  相似文献   
993.
The relationship between quality of care and the cost of the nursing workforce is of concern to policymakers. This study assesses the evidence for a relationship between the nursing workforce and patient outcomes in the acute sector through a systematic review of international research produced since 1990 involving acute hospitals and adjusting for case mix. Twenty-two large studies of variable quality were included. They strongly suggest that higher nurse staffing and richer skill mix (especially of registered nurses) are associated with improved patient outcomes, although the effect size cannot be estimated reliably. The association appears to show diminishing marginal returns.  相似文献   
994.
OBJECTIVE: The growing awareness of female breast cancer has led to increased sensitivity toward pathologic breast conditions in children and adolescents. Thus, approximately 15% of patients in child and adolescent gynecology are referred for the first time because of conspicuous features of the breast such as pain, palpable masses, and other findings on visual inspection. The aim of this study was to analyze the underlying diagnoses and diseases and determine the status of breast sonography in the diagnostic process. METHODS: The study population consisted of 62 female patients between 8 weeks and 20 years of age (1997-2002) who were examined clinically, followed by standardized sonography (7.5-13 MHz, conventional B-mode panoramic sonography). Presumed diagnoses were confirmed by biopsy in some patients (n = 16) and by follow-up with clinical examination and sonography in most cases (n = 46). RESULTS: The clinical and sonographic evaluation confirmed 4 main groups of diagnoses: benign tumors (15), developmental disturbances (14), cystic changes (11), and inherent defects (7). In the remaining cases, the findings were no abnormality (9), nipple discharge without evidence of pathologic or morphologic correlates (3), abscesses (2), and epidermoid cyst (1). CONCLUSIONS: Knowledge of regular breast development and its variants is essential for the physician. Given knowledge of the sonographic appearance of physiologic breast development and specific lesions, breast sonography is most helpful in identifying and characterizing abnormalities and guiding further investigation.  相似文献   
995.
PURPOSE: To report a retrospective study into the effects of trials on clinical decision-making regarding abdominal aortic aneurysm (AAA) patients suitable for both conventional open (OR) and endovascular aneurysm repair (EVAR). METHODS: A questionnaire was sent to 1400 Dutch surgeons and trainees. Interviewees had to choose between OR and EVAR for AAA patients with and without comorbidity. Specifically, their preferences before and after the publication of 2 randomized trials (EVAR-1 and DREAM) were polled. RESULTS: Of the 524 (37%) questionnaires returned, 223 (43%) respondents treated AAA patients. Before publication of the trials, 160 (72%) preferred OR for the patient without comorbidity and 169 (76%) preferred EVAR for the patient with comorbidity. In total, 72 (32%) respondents changed their preference after the trials were published; however, there was no overall major shift. Focusing on the different cases revealed that the OR preference was significantly enhanced for the patient without comorbidity (p<0.01), while the EVAR preference was significantly enhanced for the patient with comorbidity (p<0.05). CONCLUSION: The randomized trials have not induced major overall changes in surgical decision-making for AAA patients suitable for both EVAR and OR.  相似文献   
996.
997.
998.
The assessment of the presence of eosinophilic airway inflammation may help in predicting the steroid response in subjects with respiratory symptoms. Unlike patients with asthma, only a subset of patients with chronic obstructive pulmonary disease (COPD) benefits from steroid treatment. Fractional exhaled nitric oxide (FENO) is a useful surrogate marker for eosinophilic airway inflammation, but data on the repeatability of FENO measurements in COPD needed for the assessment of significant change are insufficient. The aim of this study was to assess the short-term repeatability of FENO measurement in subjects with moderate to very severe chronic airway obstruction compared to that in healthy subjects. We studied 20 patients with stable COPD and 20 healthy subjects, and determined FENO (flow rate 50 ml s(-1) ) three times: at baseline, 10 min and 24 h after baseline. Spirometry was performed on the first study day after the FENO measurements. The median FENO concentration in patients with COPD was 15·6 ppb, and in healthy subjects, 15·2 ppb. The coefficient of variation (CoV) for 24-h measurements was 12·4% in COPD patients, and 15·9% in healthy subjects. Among COPD patients with global initiative for chronic obstructive lung disease stage 2 disease, the CoV was 13·7%, and among those with stage 3-4 disease, 10·5%. The findings indicate that the short-term repeatability of FENO measurement in patients with moderate to very severe COPD is equally good as in healthy subjects. A change in FENO exceeding 24% is likely to reflect a minimum measurable change in COPD.  相似文献   
999.
A randomized, double-blind study comparing single-dose chlamydia therapies of oral rifalazil (25 mg) and azithromycin (1 g) was conducted in 82 women with uncomplicated genital Chlamydia trachomatis infection. The microbiologic cure rate of C. trachomatis with rifalazil (n = 33) was 84.8% at the visit on day 22 to 26 (test-of-cure visit), versus 92.1% with azithromycin (n = 38), and the number of treatment failures in each group was 5 and 3, respectively. The difference in cure rate was −7.3%, with a lower limit of the 95% confidence interval (95% CI) of −22.5, and thus, noninferiority was not established at the prespecified margin (lower limit of CI of −15%). The overall treatment-emergent adverse event (TEAE) and treatment-related TEAE rates were lower in the rifalazil group (68% and 55%) than in the azithromycin group (71% and 62%), respectively. Subjects classified as treatment failures at day 22 to 26 had a lower mean plasma concentration of rifalazil at the visit on day 8 to 12 than those classified as treatment cures, but this difference was not significant; however, the levels were similar for both groups at the visit on day 22 to 26. A single 25-mg dose of rifalazil was well tolerated and eradicated C. trachomatis in most of these women with uncomplicated genital C. trachomatis infection. (The study was registered at clinicaltrials.gov under registration no. NCT01631201).  相似文献   
1000.
PURPOSE: The purpose of this trial was to compare the efficacy of pelvic floor muscle exercises and manometric biofeedback for post-micturition dribble (PMD) in men with erectile dysfunction. METHODS: Fifty-five men with erectile dysfunction (median age 59.2 years; range 22-78) were enrolled from a local urology clinic. Twenty-eight subjects were randomized to an intervention group and received pelvic floor muscle exercises including a strong post-void "squeeze out" pelvic floor muscle contraction, biofeedback, and suggestions for lifestyle changes. Twenty-seven control subjects were solely advised on lifestyle changes. The PMD status, anal manometry, and digital anal muscle grade were assessed at baseline, 3, and 6 months. After 3 months, the control group received the intervention with pelvic floor muscle exercises and biofeedback. Both groups were followed for an additional 3 months of home exercises. An independent assessor who was blinded to the grouping assessed the PMD status of subjects at 3 and 6 months. RESULTS: Thirty-six (65.5%) of the 55 subjects reported PMD at baseline. At 3 months, there was significant reduction in PMD after intervention (p=0.001) compared to the control subjects (p=0.102). In both groups combined after 3 months of pelvic floor muscle exercises and 3 months of home exercises, 27 (75%) subjects became asymptomatic of PMD, 3 (8.3%) improved, 5 (13.9%) dropped out, and 1 (2.8%) subject still reported PMD. PMD was not correlated to age, erectile function, anal manometric pressure, or digital anal muscle grade. CONCLUSION: Pelvic floor muscle exercises including a post-void "squeeze out" pelvic floor muscle contraction are an effective treatment for post-micturition dribble in men with erectile dysfunction.  相似文献   
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