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21.
Alexander Goldberg Ursula Schlötzer-Schrehardt Theo Seiler 《International ophthalmology》1997,21(3):117-120
We report the first case of a unilateral microcysticMeesmann‘s epithelial dystrophy, observed in the left cornea of a 43-year-old
patient. The diagnosis was verified histologically by the unilateral occurrence of a ’peculiar substance‘ within epithelial
cysts and within the cytoplasm of the corneal epithelial cells. In an attempt to resolve thepatient‘s frequent corneal erosions,
we performed an autologous stem cell transplantation from the non-involved right eye. The results are, so far, satisfactory.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
22.
Lactones, XVI: Synthesis of 4,9-Dihydropyrano[3,4-b]indol-1(3H)-ones from α-Ethoxalyl-δ-valerolactone Treatment of α-ethoxalyl-δ-valerolactone (1) with diazotized anilines and indolization of the intermediate hydrazones 4 leads to the pyranoindolones 5 . Compared to the recently reported reaction of α-ethoxalyl-γ-butyrolactone with arylhydrazines2), this synthesis is more versatile with regard to variation of substituents at the aromatic ring. Stereochemistry and reactivity of the α-arylhydrazonolactones are discussed. 相似文献
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26.
Gudrun Bornh?ft Stefanie Maxion-Bergemann Ursula Wolf Gunver S Kienle Andreas Michalsen Horst C Vollmar Simon Gilbertson Peter F Matthiessen 《BMC medical research methodology》2006,6(1):56
Background
It is often stated that external validity is not sufficiently considered in the assessment of clinical studies. Although tools for its evaluation have been established, there is a lack of awareness of their significance and application. In this article, a comprehensive checklist is presented addressing these relevant criteria. 相似文献27.
Wolfram Grimm Jens Winzenburg Ursula Knop Jürgen Hoffmann Volker Menz Frank Grote Bernhard Maisch 《Annals of noninvasive electrocardiology》1997,2(1):20-26
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC. 相似文献
28.
Intramolecular Alkylations of Aromatic Compounds, XVII1): — Synthesis of trans-3,10b-Dimethyl-1,2,3,4,4a,5,6,10b-octahydrobenzo(f)isoquinoline From the cyanhydrine 5b , easily obtained from 4 and trimethylsilyl cyanide, the lactone 6 is prepared, hydrogenation of which gives a mixture of the lactam 7a and the lactone 8 . Compound 7a is reduced to the secondary base 9 , which by treatment with acid is dehydrated to 10 and rearranges to give the isomer 11 , too. Attempted cyclization of the aminoalcohol 12 fails to give 9 or 10 . Rather, the furan 13 is isolated as the final product. N-methylation 10 → 14 and subsequent hydrogenation furnish the 4:1 trans/cis-mixture 2a, b , from which the title compound is separated by column chromatography. From 11 the stereomers 18a, b can be prepared analogously. 相似文献
29.
Hoschek Stefan Hoschek-Risslegger Ursula Fiegl Michael Zabernigg August Pall Georg Auberger Thomas Gunsilius Eberhard Schmid Thomas Jamnig Herbert Hilbe Wolfgang 《Wiener Medizinische Wochenschrift》2007,157(21):562-568
Wiener Medizinische Wochenschrift - Aggressives Tumorwachstum, frühe Metastasierung und hohe Assoziation mit intensivem Nikotinkonsum sind die Charakteristika des kleinzelligen... 相似文献
30.
We have recently demonstrated that the number of small sensory neurons of the A-δ- and C-fiber group in lumbar dorsal root ganglia labeled with horseradish peroxidase (HRP) is selectively decreased 7 days after Nd:YAG laser irradiation of the tibial nerve in the rat. In contrast, the number of large diameter sensory neurons was not affected by laser application. In an attempt to clarify the fate of motoneurons after laser irradiation of their peripheral axons, the numbers of lumbar motoneurons retrogradely labeled with HRP 7 days after Nd:YAG laser irradiation of the tibial nerve have been determined in rats. Our results show that the number of HRP-labeled motoneurons in lumbar segments L6 to L3 is not altered to a significant extent after laser irradiation of their peripheral axons (laser-treated side, 767 ± 10 cells vs control side, 808 ± 19; n = 5, mean ± SEM). In addition, no difference was detected in the mean value or the distribution of soma cross-sectional areas of labeled motoneurons on the laser-treated side and the control side. Specifically, the numbers of HRP-labeled small diameter motoneurons, which are presumably γ in type and have a conduction velocity similar to sensory neurons of the A-δ group, were not affected by laser application. Possible mechanisms of the differential vulnerability of sensory neurons as compared to motoneurons of similar size are discussed. 相似文献