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11.
The synthesis of the title compounds starting from 2-Chlormethylbenzdioxan and Tetrahydroisochinolines is presented. Their actions on the platelet aggregation and the inhibition of alpha-adrenoceptors at the isolated rabbit aorta and the vas deferens of the guinea pig were investigated. 相似文献
12.
Claudia Brogsitter Thomas Grüning Reiner Weise Peter Wielepp Oliver Lindner Reiner K?rfer Wolfgang Burchert 《Journal of nuclear medicine》2005,46(1):19-24
(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
13.
Ohne Zusammenfassung 相似文献
14.
Dr. J.-T. Gräsner M. Fischer K. H. Altemeyer J. Bahr B. W. Böttiger V. Dörges R. Franz A. Gries H. Krieter M. Messelken T. Rosolski M. Ruppert T. Schlechtriemen J. Scholz J. Schüttler B. Wolke J. F. Zander 《Notfall & Rettungsmedizin》2005,8(2):112-115
Within the scope of the symposium “Rescue Medicine in Germany” (held at the Reisensburg near Ulm in 2002), the need for a standardized data acquisition set for prehospital cardiac arrest patients was identified. Therefore, the working group “Emergency Medicine” of the German Society of Anesthesiology and Intensive Care Medicine (DGAI) created a nationwide data acquisition system for primary medical care in prehospital cardiac arrest patients treated with cardiopulmonary resuscitation procedures. The system is in full accordance with the “Utstein style.” Integration of this data acquisition system, for example into the “Dortmund protocol,” is providing a standardized data web base of all acquired prehospital data analyze and to compare processing and structural quality. As additional modules for this nationwide data web base system, an inhospital module “further clinical treatment” and a “long-term follow-up” module are currently in the developmental process. 相似文献
15.
16.
Gerhard Koßmehl Andrea Fluthwedel Horst Schfer 《Macromolecular chemistry and physics.》1992,193(1):157-166
Basic materials for contact lenses were obtained by radical copolymerization of linear α,ω-bis(methacryloyloxy)-terminated oligo- and poly(dimethylsiloxane)s, methyl methacrylate and 2,2,3,3,4,4,4-heptafuorobutyl methacrylate. Oxygen permeabilities, contact angles and ball indentation hardness were determined. 相似文献
17.
Tissue engineering of bone for mandibular augmentation in immunocompetent minipigs: preliminary study. 总被引:4,自引:0,他引:4
Andreas Gr?ger Svea Kl?ring Hans-Albert Merten J?rg Holste Christian Kaps Michael Sittinger 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2003,37(3):129-133
Large mandibular defects caused by trauma, infection or resection of a tumour are still a major problem for plastic and maxillofacial surgeons. The modern concept of tissue engineering combines the osteoinductive effects of osteogenic cells with a suitable scaffold structure to promote differentiation of osteoblasts and optimal matrix production. Critical size mandibular bone defects were therefore made to investigate the osteogenic potential of periosteal cells and a bioabsorbable polymer fleece (Ethisorb 510) in minipigs. Periosteal cells were isolated from four minipigs, expanded in vitro and seeded with fibrin glue into Ethisorb 510 fleeces. Tissue constructs were used to repair critical size mandibular defects and compared with two minipigs with untreated bone defects. Bone healing was evaluated after 90 and 180 days by radiographs and a histological scoring system. The radiographs showed increased radiodensity of defects filled with the cell-fibrin-fleece-constructs compared with the untreated control group after 90 and 180 days in vivo. The defects repaired by the cell-fibrin-scaffolds (180 days in vivo) obtained the highest histological mean score 2.9 (range 2-3), while defects filled by cell-fibrin-scaffolds (90 days in vivo) achieved a mean score of 2.1 (range 2-3). In contrast, the control group (n = 2) scored 1 and 2. The results show that a combination of periosteal cells and polymer fleeces may be a promising approach for clinical mandibular augmentation. 相似文献
18.
F. G. Pajonk H. H. Bartels K. A. S. Grünberg Hp. Moecke 《Notfall & Rettungsmedizin》2002,5(2):110-115
Pre-clinical psychiatric emergency situations (PES) have been identified to be the third major reason for emergency physician (EP) calls with a frequency of approximately 10%. Until now, there are no investigations about regional differences between urban and rural regions in frequencies, diagnoses, or treatment necessities of PES. A retrospective analysis of all anonymised EP protocols of one year in a metropolitan (Hamburg) and a rural region (Schaumburg County) was performed with the same methodological approach. In both regions, the frequency of PES was revealed to be near 10%. Gender and age of psychiatric patients as well as reasons for calls were comparable. In Schaumburg County, much less disturbances due to illegal drugs were observed. However, more patients had to be treated because of suicide attempts and alcoholism. All in all, disturbances seemed less life-threatening than in the metropolitan region. In conclusion, frequency and kind of PES do not differ substantially between rural and urban regions. Considering the prevalence of PES, the particularities in diagnosis and treatment and the dissipation of institutionalised psychiatric care mainly in rural regions, more training in psychiatric subjects is needed. 相似文献
19.
G Duncker H A Horst K D Kolenda F Schenck 《Klinische Monatsbl?tter für Augenheilkunde》1988,193(6):622-626
Using the Farnsworth-Munsell 100-hue test, investigations were carried out in 14 patients with subtoxic to toxic serum concentrations of digoxin (greater than 2.0 ng/ml) and 13 patients with subtoxic to toxic serum concentrations of digitoxin (greater than 30 ng/ml), in order to detect color vision deficiencies related to serum levels of digitalis. As compared to the control group (n = 24) the total error scores were significantly increased for both glycosides and all serum level ranges. No evidence was found indicating that digoxin and digitoxin influence color vision differently. The FM 100-hue test indicated definite improvements in the digoxin group within one day of discontinuing the glycosides, while the digitoxin group only started to normalize a week later. The results are discussed, taking the different pharmacokinetics of the two digitalis glycosides into account. 相似文献
20.
Horst Helbig Ulrich Kellner Norbert Bornfeld Michael H. Foerster 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1996,93(6):647-654
Hintergrund: Verschiedene Indikationen für glask?rperchirurgische Eingriffe bei Komplikationen der diabetischen Retinopathie haben sich
etabliert. Jedoch gibt es wenig Daten zu der Frage, in welchen Situationen auf einen Eingriff wegen aussichtsloser funktioneller
Prognose verzichtet werden sollte.
Material und Methode: Die Krankengeschichten von 389 Patienten, die zwischen 1990 und 1994 in unserer Klinik wegen Komplikationen der diabetischen
Retinopathie vitrektomiert worden sind, wurden retrospektiv analysiert. Die Nachbeobachtung betrug mindestens 6 Monate, im
Median 26 Monate. Mit multivariaten, logistischen Regressionsanalysen wurden Faktoren ermittelt, die mit schlechten postoperativen,
funktionellen Ergebnissen korrelieren. Ein mathematisches Modell wurde entwickelt, welches die Einsch?tzung der Prognose für
verschiedene Ausgangssituationen erlaubt.
Ergebnisse: Bei 45 Augen (12%) stieg der postoperative Visus nicht über 1/50. Risikofaktoren waren Ablatio der Makula, Ausdehnung der
Ablatio, Rubeosis und Dauer der Visusminderung. ?hnliche Risikofaktoren gelten auch für Revisionsoperationen. Bei einem Auge
mit totaler Traktionsablatio von über 6 Monaten Dauer und Rubeosis liegt die berechnete Wahrscheinlichkeit für einen postoperativen
Visus über 1/50 lediglich bei 2%.
Schlu?folgerungen: Bei totaler Traktionsablatio, insbesondere bei Rubeosis und l?ngerem Bestehen der Ablatio, ist die Prognose extrem schlecht.
Auf operative Ma?nahmen sollte hier verzichtet werden.
相似文献