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991.
The aim of this study was to evaluate two different magnetic resonance (MR) techniques for the noninvasive assessment of intracoronary blood flow. Coronary blood flow velocities were measured invasively in 26 angiographically normal segments of 12 patients. Noninvasive measurements were performed in identical segments with two MR techniques using a 1.5 T MR tomograph (ACS NT, Philips). A single breath-hold technique (temporal resolution: 140 msec) and a similar non-breath-hold technique with prospective navigator correction and improved temporal resolution (45 msec) were used. Maximal coronary flow velocities determined by MR correlated closely with invasive measurements (breath-hold: r = 0.70; navigator: r = 0.86); however, a significant underestimation of the MR measurements was found (slope = 0.33 and 0.37). The relative difference from the invasive method was lower for the navigator technique compared with the breath-hold technique (P<0.02). Both MR techniques allow the determination of coronary blood flow velocities. The higher temporal resolution and shorter acquisition window of navigator-corrected non-breath-hold techniques lead to increased accuracy. This approach is a further step toward the diagnostic use of MR flow measurements in coronary artery disease.  相似文献   
992.
PURPOSE: This retrospective study was designed to evaluate the role of adjuvant radiotherapy for surgically treated endometrial carcinoma. PATIENTS AND METHODS: From 1980 through 1988, 541 patients were treated with either intravaginal cuff irradiation with a high-dose-rate (HDR) Iridium-192 remote afterloading technique (n = 294) or with combined HDR-brachytherapy and additional external pelvic irradiation to 54 Gy (n = 247) after surgery for endometrial cancer. Afterloading irradiation was administered in 4 fractions 4 to 6 weeks after surgery. A dose of 30 Gy was delivered at a depth of 0.5 cm from the vaginal mucosa. RESULTS: Patients with HDR-brachytherapy alone showed a 5-year survival of 94.3% for Stage I and 73.6% for Stage II (p = 0.0007). Patients who received both brachytherapy and additional external pelvic irradiation had a 5-year survival of 94.1% for Stage I, 81.1% for Stage II, 70.4% for Stage III and 46.9% for Stage IV (p = 0.0001). The main predictors for survival in a multivariate analysis were stage and grading. Patients with combined radiotherapy had a local recurrence rate of 3.2%, whereas patients with brachytherapy alone who were better selected and had more favorable prognostic factors showed a recurrence rate of 2%. Low-risk patients (Stage I, Grade 1, low infiltration) in the HDR-brachytherapy group had 6 relapses, mainly caused by insufficient treatment on the basis of papillary histology. High-risk patients with poorly differentiated tumors, which infiltrate more than half the myometrial wall might benefit from additional external radiotherapy in terms of reduction of local recurrence and better survival. Five-year actuarial survival rate was 93.6% after combined radiotherapy vs 86.7% after brachytherapy alone. Complications were graded according to the RTOG scoring system. Severe late complications were fistulas of bladder and/or bowel, which occurred in 2.8% in the combined radiotherapy group, and 0.7% in the HDR brachytherapy group. CONCLUSIONS: Low-risk patients should be generally treated postoperative with HDR-brachytherapy alone. Combined radiotherapy decreased pelvic relapses for high-risk patients with overall low complication rates. We conclude that an individually adjusted postoperative radiotherapy allows a well tolerated treatment with excellent results.  相似文献   
993.
994.
In medical research laboratories, computers and computer-based data collection have become more and more important. For the setup of new experimental studies, the accuracy of preparations and the timely recording of data are crucial for quality management. Because of the manifold tasks during an experiment, it is often necessary to find additional capacities to manage the workload or even to restrict the extent of the experiment. Especially the recording of different data at the same time is tremendously time-consuming, hampers expansions of new developments of the experiment, and may even represent a source of error. We present a newly developed relational database (Sunwork® Medimouse) that can manage the requirements addressed above, is easy to operate without the need of special computer knowledge, and therefore serves as tool for quality management in experimental animal research.  相似文献   
995.
996.
INTRODUCTION: Serous cystadenomas of the pancreas are rare tumors and thought to be almost always benign. METHODS: We report our experience in the diagnosis and surgical treatment of 12 patients with these tumors. RESULTS: Between October 1993 and December 1998, 41 patients with cystic tumors of the pancreas underwent surgical resection; in 12 cases (11 women, 1 man) a serous cystadenoma (10 micro-cystic, 2 oligo-microcystic) was found. Only 6 (50%) patients had symptoms. The mean tumor size was 4.8 (2.7-10) cm. Ultrasound, CT and MRT usually could detect the mass, but differentiation with other cystic lesions was not reliable. All tumors were resected: 4 Whipple procedures, 7 distal pancreatectomies and 1 segmental resection were performed. No patient died after surgery and none had to be reoperated on. CONCLUSIONS: Because of the difficulty in reliably differentiating benign and malignant lesions of the pancreas, we believe that cystic tumors of the pancreas should be resected.  相似文献   
997.
Zusammenfassung Operationsziel Korrektur einer Klauenzehenfehlstellung der Großzehe durch Rückversetzung des Musculus extensor hallucis longus und damit Ausschaltung der pathologischen Wirkung der extrinsischen Zehenmuskulatur sowie Schaffung einer aktiven Elevationswirkung auf das Os metatarsale I durch Rückversetzung des Musculus extensor hallucis longus auf das Os metatarsale I. Indikationen Funktionelle Beschwerden durch eine Klauenzehenfehlstellung der ersten Zehe infolge einer Überaktivität oder eines Übergewichts der extrinsischen über die intrinsische Muskulatur. Voraussetzung für die Operation ist ein normaler oder fast normaler Kraftgrad des Musculus extensor hallucis longus. Die alleinige Operation nach Robert Jones ist nur bei flexibler Flexionsstellung des Os metatarsale I wirksam; bei fixierter Stellung sollte sie mit einer extendierenden Osteotomie der Basis des Os metatarsale I kombiniert werden. Kontraindikationen Fehlende Kraft des Musculus extensor hallucis longus. Operationstechnik Ansatznahes Ablösen der Sehne des Musculus extensor hallucis longus und transossäre Rückversetzung auf das Os metatarsale I. Ergebnisse 65 Patienten wurden von 06/1990 bis 07/1997 in einer modifizierten Technik nach Robert Jones operiert. 51 von ihnen (19 Frauen, 32 Männer) mit 81 Rückversetzungen der Sehne des Musculus extensor hallucis longus konnten nach durchschnittlich 42 Monaten (neun bis 88 Monate) kontrolliert werden. Nach den Bewertungskriterien von Tynan und Klenerman waren die Patienten mit dem Ergebnis 36-mal sehr zufrieden, 38-mal bedingt zufrieden und sieben mal unzufrieden. Die Zehenfehlstellung wurde bei allen Füßen beseitigt. Summary Objectives Transfer of the extensor hallucis longus tendon to the neck of the first metatarsal to correct a claw toe deformity of the great toe. This transfer counteracts the pathologic action of the extrinsic toe muscles and produced an active elevation of the first metatarsal. Indications Activity-related complaints due to a claw deformity of the great toe secondary to a hyperactivity of the extrinsic muscles or a predominance of the extrinsic over the intrinsic muscles. Prerequisite: normal or near normal power of the extensor hallucis longus. This procedure is only indicated in instances of a flexible malposition of the first metatarsal. It must be combined with an extension osteotomy of the first metatarsal for a fixed deformity. Contraindications Insufficient power of the extensor hallucis longus. State after compartment syndrome or after posttraumatic malalignment. Surgical Technique Detachment of the tendon of the extensor hallucis longus close to its insertion and transfer to the neck of the first metatarsal. Results Between June 1990 and July 1997, the modified Jones technique was used in 65 patients. In 51 patients (19 women, 32 men) with 81 transfers, a follow-up examination was done after an average of 42 months (9 to 88 months). Using the assessment criteria of Tynan and Klenerman, the patients regarded the result as excellent in 36 cases, as satisfactory in 38 and as unsatisfactory in 7. The malposition of the toe was corrected in all feet.  相似文献   
998.
BackgroundObesity and its health consequences will dominate health care systems in many countries during the next decades. However, the body mass index (BMI) optimum in relation to all-cause mortality is still a matter of debate.Material and MethodsData of the Vorarlberg Health Monitoring & Prevention Program (VHM&PP, 1985–2005) and data provided by the Main Association of Austrian Social Security Institutions (MAASSI, 2005–2015) were analyzed. Information was available on age, sex, smoking status, measured height and weight, and mortality. Generalized additive models were used to model mortality as a function of BMI, calendar time, age, and follow-up.ResultsIn MAASSI (N = 282,216, 46.0% men), men and women were on average 2.7 years older than in VHM&PP (N = 185,361, 46.1% men). Average BMI was slightly higher in men (26.1 vs 25.7 kg/m2) but not in women (24.6 vs 24.7 kg/m2). We found an interactive effect of age and follow-up on the BMI optimum. Over age 35 years in men and 55 years in women, the BMI optimum decreased with length of follow-up. While keeping covariates fixed, BMI optimum increased slightly between 1985 and 2015 in men and women, 24.9 (95% CI, 23.9–25.9) to 26.4 (95% CI, 25.3–27.3), and 22.4 (95% CI, 21.7–23.1) to 23.3 (95% CI, 22.6–24.5) kg/m2, respectively.ConclusionAge and length of follow-up have a pronounced effect on the BMI associated with the lowest all-cause mortality. After controlling for age and length of follow-up, the BMI optimum increased slightly over 30 years in this large study sample.Key words: BMI, mortality, age, secular trend, length of follow-up  相似文献   
999.
Background: Gastrointestinal hormones (GIHs) are crucial for the regulation of a variety of physiological functions and have been linked to hunger, satiety, and appetite control. Thus, they might constitute meaningful biomarkers in longitudinal and interventional studies on eating behavior and body weight control. However, little is known about the physiological levels of GIHs, their intra-individual stability over time, and their interaction with other metabolic and lifestyle-related parameters. Therefore, the aim of this pilot study is to investigate the intra-individual stability of GIHs in normal-weight adults over time. Methods: Plasma concentrations of ghrelin, leptin, GLP-1 (glucagon-like-peptide), and PP (pancreatic polypeptide) were assessed by enzyme-linked immunosorbent assay (ELISA) in 17 normal-weight, healthy adults in a longitudinal design at baseline and at follow-up six months later. The reliability of the measurements was estimated using intra-class correlation (ICC). In a second step, we considered the stability of GIH levels after controlling for changes in blood glucose and hemoglobin A1 (HbA1c) as well as self-reported physical activity and dietary habits. Results: We found excellent reliability for ghrelin, good reliability for GLP1 and PP, and moderate reliability for leptin. After considering glucose, HbA1c, physical activity, and dietary habits as co-variates, the reliability of ghrelin, GLP1, and PP did not change significantly; the reliability of leptin changed to poor reliability. Conclusions: The GIHs ghrelin, GLP1, and PP demonstrated good to excellent test–retest reliability in healthy individuals, a finding that was not modified after adjusting for glucose control, physical activity, or dietary habits. Leptin showed only moderate to poor reliability, which might be linked to weight fluctuations, albeit small, between baseline and follow-up assessment in our study sample. Together, these findings support that ghrelin, GLP1, and PP might be further examined as biomarkers in studies on weight control, with GLP1 and PP serving as anorexic markers and ghrelin as an orexigenic marker. Additional reliability studies in obese individuals are necessary to verify or refute our findings for this cohort.  相似文献   
1000.
The magnetic properties of non-oriented electrical steel, widely used in electric machines, are closely related to the grain size and texture of the material. How to control the evolution of grain size and texture through processing in order to improve the magnetic properties is the research focus of this article. Therefore, the complete process chain of a non-oriented electrical steel with 3.2 wt.-% Si was studied with regard to hot rolling, cold rolling, and final annealing on laboratory scale. Through a comprehensive analysis of the process chain, the influence of important process parameters on the grain size and texture evolution as well as the magnetic properties was determined. It was found that furnace cooling after the last hot rolling pass led to a fully recrystallized grain structure with the favorable ND-rotated-cube component, and a large portion of this component was retained in the thin strip after cold rolling, resulting in a texture with a low γ-fiber and a high ND-cube component after final annealing at moderate to high temperatures. These promising results on a laboratory scale can be regarded as an effective way to control the processing on an industrial scale, to finally tailor the magnetic properties of non-oriented electrical steel according to their final application.  相似文献   
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