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排序方式: 共有908条查询结果,搜索用时 31 毫秒
31.
Christian Knackstedt Marlies Arndt Karl Mischke Nikolaus Marx Fred Nieman Hanns Jürgen Kunert Patrick Schauerte Christine Norra 《Heart and vessels》2014,29(3):364-374
Congestive heart failure is frequent and leads to reduced exercise capacity, reduced quality of life (QoL), and depression in many patients. Cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICD) offer therapeutic options and may have an impact on QoL and depression. This study was performed to evaluate physical and mental health in patients undergoing ICD or combined CRT/ICD-implantation (CRT-D). Echocardiography, spiroergometry, and psychometric questionnaires [Beck Depression Inventory, General World Health Organization Five Well-being Index (WHO-5), Brief Symptom Inventory and 36-item Short Form (SF-36)] were obtained in 39 patients (ICD: 17, CRT-D: 22) at baseline and 6-month follow-up (FU) after device implantation. CRT-D patients had a higher NYHA class and broader left bundle branch block than ICD patients at baseline. At FU, ejection fraction (EF), peak oxygen uptake, and NYHA class improved significantly in CRT-D patients but remained unchanged in ICD patients. Patients with CRT-D implantation showed higher levels of depressive symptoms, psychological distress, and impairment in QoL at baseline and FU compared to ICD patients. These impairments remained mostly unchanged in all patients after 6 months. Overall, these findings imply that there is a need for careful assessment and treatment of psychological distress and depression in ICD and CRT-D patients in the course of device implantation as psychological burden seems to persist irrespective of physical improvement. 相似文献
32.
Jonathan Bishop Akiva Feintuch Nicholas A Bock Brian Nieman Jun Dazai Lorinda Davidson R Mark Henkelman 《Magnetic resonance in medicine》2006,55(3):472-477
Cardiac MR imaging in small animals presents some difficulties due to shorter cardiac cycles and smaller dimensions than in human beings, but prospectively gated techniques have been successfully applied. As with human imaging, there may be certain applications in animal imaging for which retrospective gating is preferable to prospective gating. For example, cardiac imaging in multiple mice simultaneously is one such application. In this work we investigate the use of retrospective gating for cardiac imaging in a mouse. Using a three-dimensional imaging protocol, we show that image quality with retrospective gating is comparable to prospectively gated imaging. We conclude that retrospective gating is applicable for small animal cardiac MRI and show how it can be applied to the problem of cardiac MRI in multiple mice. 相似文献
33.
Multislice spiral computed tomography coronary angiography in patients with stable angina pectoris 总被引:39,自引:0,他引:39
Mollet NR Cademartiri F Nieman K Saia F Lemos PA McFadden EP Pattynama PM Serruys PW Krestin GP de Feyter PJ 《Journal of the American College of Cardiology》2004,43(12):2265-2270
OBJECTIVES: This study was designed to prospectively evaluate the diagnostic performance of multislice spiral computed tomography (MSCT) coronary angiography for the detection of significant lesions in all segments of the coronary tree potentially suitable for revascularization. BACKGROUND: Noninvasive MSCT coronary angiography is a promising coronary imaging technique. METHODS: Sixteen-row MSCT coronary angiography was performed in 128 patients (89% men, mean age 58.9 +/- 11.7 years) in sinus rhythm with stable angina pectoris scheduled for conventional coronary angiography. Sixty percent (77 of 128) of patients received pre-scan oral beta-blockers, resulting in a mean heart rate of 57.7 +/- 7.7 beats/min. The diagnostic performance of MSCT for detection of significant lesions (> or =50% diameter reduction) was compared with that of quantitative coronary angiography (QCA). RESULTS: The sensitivity of MSCT for detection of significant lesions was 92% (216 of 234, 95% confidence interval [CI]: 88 to 95). Specificity was 95% (1,092 of 1,150, 95% CI: 93 to 96), positive predictive value 79% (216 of 274, 95% CI: 73 to 88), and negative predictive value 98% (1,092 of 1,110, 95% CI: 97 to 99). Two > or =50% lesions were missed because of motion artifacts and two because of severe coronary calcifications. The rest (78%, 14 of 18) were detected but incorrectly classified as <50% obstructions. All patients with and 86% (18 of 21) of patients without significant lesions on QCA were correctly classified by MSCT. All patients with significant left main disease or total occlusions were correctly identified on MSCT. CONCLUSIONS: Sixteen-row MSCT coronary angiography permits reliable detection of significant obstructive coronary artery disease in patients with stable angina in sinus rhythm. 相似文献
34.
Desireé McCarthy-Keith Sahadat Nurudeen Alicia Armstrong Eric Levens Lynnette K. Nieman 《Contemporary clinical trials》2010,31(1):44-48
BackgroundSubject recruitment and retention in clinical leiomyoma trials is challenging. We evaluated strategies to increase patient enrollment and completion in leiomyoma trials.Materials and methodsRandomized trials for treatment of symptomatic leiomyoma published from 2000 through 2008 were evaluated and thirteen trials were selected. Subject enrollment and completion rates, recruitment methods and reasons for patient drop-out were assessed.ResultsRecruitment by study personnel or clinic staff during evaluation for symptomatic leiomyoma was the most common strategy for enrollment. Additional methods included local media, internet postings and physician referrals. Seven to 85% of patients enrolled after screening, with a median enrollment of 70%. Sixty-five to 100% of patients completed the study after enrollment with a median completion rate of 89%. Reasons for drop-out at the screening stage included failure to meet inclusion criteria, patient refusal and patient preference for specific treatment. Commonly reported reasons for drop-out after enrollment were refusal of treatment following randomization, adverse reaction to study intervention and non-compliance with study protocol or follow-up visits.ConclusionWomen with symptomatic uterine leiomyomas may be attracted to participate in leiomyoma trials, however desire for specific treatment and persistent symptoms following intervention may hinder their participation. Randomization to placebo treatment and stringent inclusion criteria appear to adversely impact accrual. A wide range of recruiting tactics is needed and media sources or direct mailings may prove particularly effective to improve subject recruitment and retention in clinical leiomyoma trials. 相似文献
35.
Iffat N. Chowdhury Ninet Sinaii Edward H. Oldfield Nicholas Patronas Lynnette K. Nieman 《Clinical endocrinology》2010,72(4):502-506
Objective While detection of pituitary tumours with magnetic resonance imaging (MRI) may reduce diagnostic costs and improve surgical outcomes for patients with Cushing’s disease, the optimal T1‐weighted spin‐echo (SE) MRI protocol remains unknown. We hypothesized that specific MR scanning parameters influence detection of corticotropinomas. Design and patients Between December 1997 and November 2004, 21 of 84 consecutive patients with Cushing’s disease had a falsely negative initial pituitary MRI study and a lesion identified subsequently at the National Institutes of Health Clinical Center. This study retrospectively reviewed and compared technical parameters used for the two pituitary T1‐weighted SE MRIs in 18 patients with available scans. Measurements Repetition time (TR)/echo times (TE), field of view (FOV), matrix size, magnetic field strength, slice thickness, use of gadolinium contrast and the time interval between studies were recorded. Results The MRI interscan interval was 5·4 ± 1·1 months. All scans used gadolinium, matrix sizes were similar and nearly all had 3‐mm thick slices. Parameters that differed between the NIH‐ and externally performed scans were: TR (400 ms vs. 492 ± 19 ms, P = 0·0002); TE (10·3 ± 0·5 vs. 17·2 ± 1·2 ms, P = 0·0003); FOV (12 × 12 cm vs.17 ± 0·6 × 18 ± 0·7 cm, P < 0·0001). Immunohistochemistry of tumours resected at transsphenoidal surgery confirmed all to be corticotropinomas. Conclusions Not all ‘T1‐weighted SE’ scans are equally accurate. MRI technique, particularly FOV and TR/TE value, influences results. We recommend that endocrinologists consider pituitary MRI parameters when interpreting the results. 相似文献
36.
Sarlis NJ Chanock SJ Nieman LK 《The Journal of clinical endocrinology and metabolism》2000,85(1):42-47
Because high circulating levels of glucocorticoids impair immunity and predispose to infections, we evaluated whether indices of cortisol (F) production could predict infections in patients with Cushing syndrome (CS) caused by ectopic production of ACTH (EA). Charts of 54 consecutive patients with untreated EA, without underlying diagnosis of small cell carcinoma of the lung, were reviewed, and types of infections, white blood cell (WBC) count, fever, as well as the glucocorticoid indices [0800 h F, daily urine F excretion (UFC), and daily urine 17-hydroxysteroid/g creatinine excretion (17OHS)], were recorded. Thirty-five patients had no or clinically mild infection; the remaining 19 patients had severe, systemic infection (n = 13) and/or sepsis (n = 6), including either bacterial or opportunistic pathogens or both (73.7%, 42.1%, and 13.8%, respectively). The latter group of patients had significantly higher indices of hypercortisolism (F, UFC, and 17OHS) than those with mild or no infections, but these indices did not correlate with temperature or WBC count. Thresholds for identifying severe infection were selected for maximal positive predictive value and were: F, 43.1 microg/dL; UFC, 2000 microg/day; and 17OHS, 35 mg/g creatinine. The most accurate discriminator for severe infection was 17OHS, based on a positive predictive value of 64.7%. Our data strongly suggests that the likelihood for a bacterial or opportunistic infection in CS patients, even without underlying small cell carcinoma of the lung, is greatest in patients with extreme hypercortisolism. The predictive value of total WBC count or the presence of an elevated temperature is not sufficient to identify patients with severe, life-threatening infection. 相似文献
37.
Daily administration of the progesterone antagonist RU 486 prevents implantation in the cycling guinea pig. 总被引:1,自引:0,他引:1
M C Batista T L Bristow J Mathews W S Stokes D L Loriaux L K Nieman 《American journal of obstetrics and gynecology》1991,165(1):82-86
Since progesterone is required to prepare the endometrium for implantation of an embryo, a progesterone antagonist may inhibit nidation and thus prevent pregnancy. We addressed this possibility in the guinea pig, the small laboratory animal whose reproductive physiology most resembles that of women. Daily administration of the antiprogestin RU 486 (0, 1, 2, or 3 mg/kg, subcutaneously) for 9 days after mating inhibited implantation in a dose-dependent fashion. When this compound was given daily throughout the estrous cycle, cyclic vaginal changes, ovulation, and mating were suppressed in up to 17%, 28%, and 55% of animals, respectively. Two of seven mated female animals receiving RU 486, 1 mg/kg/day, had implantation sites. Nidation was completely blocked at higher doses. Thus daily antiprogestin administration prevented pregnancy in sexually active, normally cycling guinea pigs. A similar strategy using a daily antinidatory dose of an antiprogestin may offer a novel approach to human fertility control. 相似文献
38.
39.
40.
Evers S Voss G Nieman F Ament A Groot T Lodder J Boreas A Blaauw G 《Health policy (Amsterdam, Netherlands)》2002,61(1):21-42
In order to provide tailor-made care, governments are considering the implementation of output-pricing based on hospital case-mix measures, such as diagnosis related groups (DRG). The question is whether the current DRG classification system can provide a satisfactory prediction of the variance of costs in stroke patients and if not, in what way other variables may enhance this prediction. In this study, data from 731 stroke patients hospitalized at University Hospital Maastricht during 1996-1998 are used in the cost analysis. The DRG classification for this group uses information--in addition to the DRG classification operation or no operation--on the patient's age combined with discharge status. The results of regression analysis show that using DRGs, the variance explained in the costs amounts to 34%. Adding other variables to the DRGs, the variance explained increases to about 61%. Additional factors highly correlating with inpatient costs are the level of functioning after stroke, comorbidity, complications, and 'days of stay for non-medical reasons'. Costs decreased for stroke patients discharged during the latter part of the years studied, and if stroke patients happened to die during their hospital stay. The results do suggest that future implementation of output-pricing based on the DRG case-mix measures is feasible for stroke patients only if it is enhanced with information on complications and the level of functioning. 相似文献