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OBJECTIVE: To assess the effects of adding combined estradiol/norethisterone acetate therapy (CENT) to goserelin acetate treatment (GA) of dysfunctional uterine bleeding (DUB) in perimenopausal women. METHODS: In a randomized, placebo-controlled, double-blind trial followed by an open follow-up study, 31 perimenopausal women with DUB were recruited from gynecological outpatient departments of two Dutch hospitals and randomized for treatment with either GA/placebo or GA/CENT for 6 months followed by 18 months of GA/CENT for all. The main outcome measures were abdominal pain, number of bleeding days, double-layer endometrial thickness (DET), Greene climacteric score (GCS), visual analog scale for well-being, bone mineral density (BMD) and mammographic density (BI-RAD score). RESULTS: Abdominal pain, number of bleeding days and DET decreased in both groups, the between-group difference in decrease not being statistically significant. GCS initially showed significant improvement in the GA/CENT group. BMD decreased significantly in the GA/placebo group (-4.1%) compared with the GA/CENT group (-0.3%). Another 18 months of GA/CENT did not result in a lasting difference in BMD between groups. BI-RAD scores did not differ significantly between or within the two groups. CONCLUSIONS: Adding CENT to GA treatment for DUB in perimenopausal women initially prevented BMD loss and improved climacteric complaints, while having no negative impact on vaginal bleeding, abdominal pain or BI-RAD scores. However, prolonged treatment did not result in a lasting prevention of bone loss.  相似文献   
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Screening of potential MRSA-positive patients at hospital admission is recommended in German and international guidelines. This policy has been shown to be effective in reducing the frequency of nosocomial MRSA transmissions in the event of an outbreak, but the influence of screening on reducing hospital-acquired MRSA infections in a hospital setting where MRSA is endemic is not yet well-documented. This study describes the effect of hospital-wide screening of defined risk groups in a 700-bed acute care hospital during a period of 19 months. In a cohort study with a 19-month control period, the frequencies of hospital-acquired MRSA infections were compared with and without screening. In the control period, there were 119 MRSA-positive patients, of whom 48 had a hospital-acquired MRSA infection. On the basis of this frequency, a predicted total of 73.2 hospital-acquired MRSA infections was calculated for the screening period, but only 52% of the expected number (38 hospital-acquired MRSA infections) were observed, i.e., 48% of the predicted number of hospital-acquired MRSA infections were prevented by the screening programme. The screening programme was performed with minimal effort and can therefore be recommended as an effective measure to help prevent hospital-acquired MRSA infections.  相似文献   
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(18)F-FDG PET is an important diagnostic tool for detecting myocardial viability in patients with coronary artery disease. In combination with perfusion scanning, (18)F-FDG PET allows differentiation between reversibly and irreversibly damaged myocardium and selection of patients likely to benefit from revascularization. Viability PET is usually performed in two-dimensional (2D) mode. Taking into account the rising number of three-dimensional (3D)-only scanners, a validation of 3D acquisition is required. METHODS: Twenty-one patients with coronary artery disease referred for (18)F-FDG PET underwent an imaging protocol of nongated 2D (2D-NG) and gated 2D (2D-G) acquisitions for 15 min each, followed by 3D gated acquisitions for 10 min (3D-10) and 5 min (3D-5), using an ECAT Exact HR+ scanner. Results were analyzed using a 20-segment polar map in terms of activity concentration (Bq/mL), viability (50% uptake threshold), regional activity distribution, visual assessment of viability based on a 3-point rating scale, and left ventricular ejection fraction. RESULTS: Activity concentration measured in each segment with 2D-G, 3D-10, and 3D-5 showed a good linear correlation with 2D-NG. Quantitative viability assessment with 3D-5 gave a sensitivity of 84% and a specificity of 98%, compared with 2D-NG. No differences in regional activity distribution and visual viability assessment were found between the various protocols. Left ventricular ejection fractions obtained with 3D-10 and 3D-5 showed a good linear correlation with those measured with 2D-G. CONCLUSION: An ECG-gated 3D imaging protocol gave results comparable to those of 2D acquisition with regard to absolute and regional myocardial activity distribution, left ventricular function, and visual viability assessment. Sensitivity for viability assessment with a 50% uptake threshold was significantly less with 3D, but specificity was maintained. This protocol delivers a clinical performance nearly equivalent to that of 2D acquisition.  相似文献   
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Background: Volatile anesthetics are commonly used for general anesthesia. However, these can induce profound cardiovascular alterations. Xenon is a noble gas with potent anesthetic and analgesic properties. However, it is uncertain whether xenon alters myocardial function. The aim of this study was therefore to investigate left ventricular function during anesthesia with xenon compared with isoflurane.

Methods: The authors performed a randomized multicenter trial to compare xenon with isoflurane with respect to cardiovascular stability and adverse effects in patients without cardiac diseases scheduled for elective surgery. Two hundred fifty-nine patients were enrolled in this trial, of which 252 completed the study according to the protocol. Patients were anesthetized with xenon or isoflurane, respectively. Before administration of the study drugs and at four time points, the effects of both anesthetics on left ventricular function were investigated using transesophageal echocardiography.

Results: Global hemodynamic parameters were significantly altered using isoflurane (P < 0.05 vs. baseline), whereas xenon only decreased heart rate (P < 0.05 vs. baseline). In contrast to xenon, left ventricular end-systolic wall stress decreased significantly in the isoflurane group (P < 0.05 vs. baseline). Velocity of circumferential fiber shortening was decreased significantly in the xenon group but showed a more pronounced reduction during isoflurane administration (P < 0.05 vs. baseline). The contractile index (difference between expected and actually measured velocity of circumferential fiber shortening) as an independent parameter for left ventricular function was significantly decreased after isoflurane (P < 0.0001) but unchanged using xenon.  相似文献   

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Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists.  相似文献   
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After p.o. administration of 5-piperidino-7-[N-pentyl-N-(beta- hydroxyethyl)]amino-s-triazolo[1,5-a]pyrimidine (1; AR 12463) more than 15 metabolites were isolated from urine and feces of male Wistar rats. Only small amounts of unchanged 1 were observed. The structure of 12 metabolites was elucidated or proposed on the basis of UV-, 13C NMR- and mass spectra. Main metabolites are 5-piperidin-4'-olyl-7-[N-pentyl-N-(beta- hydroxyethyl)]amino-s-triazolo[1,5-a]pyrimidine and 5-piperidin-4'-olyl-7-[N-pent-4-olyl-N-(beta-hydroxyet hyl)]amino-s- triazolo[1,5-a]pyrimidine. The other metabolites are mainly hydroxy- or ketopentyl derivatives and piperidinoles or piperidinones, respectively. Conjugates of most of the metabolites were identified, but the ratio phase-I/II metabolites was about 3:1. In contrast to trapidil, 5-methyl-7-diethylamino-s- triazolo[1,5-a]pyrimidine, no hydroxy derivatives of the bicyclic system were observed. The major part of unchanged 1 and metabolites is excreted via kidneys.  相似文献   
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