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1.
We correlated MRI features with histopathological findings in an HIV-positive patient with vacuolar myelopathy. On MRI symmetrical
nonenhancing high-signal areas in the posterior columns on T2-weighted images result from extensive vacuolation visible on
histological sections.
Received: 18 November 1997 Accepted: 23 March 1997 相似文献
2.
O D Hensens J M Liesch D L Zink J L Smith C F Wichmann R E Schwartz 《The Journal of antibiotics》1992,45(12):1875-1885
Pneumocandin B0 (6) and six related lipopeptides are antifungal and anti-Pneumocystis carinii agents from mutants of Zalerion arboricola, whose structures were determined mainly on the basis of spectroscopic analysis. They belong, along with pneumocandin A0 (L-671,329) previously isolated from these laboratories, to the echinocandin class of antifungal agents. The product from base-catalyzed ring opening involving the hemiaminal position of the dihydroxyornithine residue of B0, has been clearly defined as 6b. Modifications were limited to the 3-hydroxy-4-methylproline, 3,4-dihydroxyhomotyrosine and 4,5-dihydroxyornithine residues of pneumocandin A0. 相似文献
3.
4.
Zusammenfassung. Der klinische Verlauf bei polytraumatisierten Patienten wird durch das h?ufige Auftreten schwerwiegender immunologischer
Komplikationen beeintr?chtigt. Die Immunantwort auf schweres Trauma kann durch die vermehrte Freisetzung proinflammatorischer
Mediatoren über das „systemic inflammatory response syndrome (SIRS)“ zum Mehrorganversagen [„multisystem organ failure (MOF)“]
führen, welches mit einer Letalit?t von bis zu 80 % behaftet ist. Charakteristisch für die Entwicklung des Multiorganversagens
ist das Auftreten des „remote organ failure (ROF)“, eine Fehlfunktion von Organen, die durch das eigentliche Trauma keinen
direkten Schaden erlitten haben. Diese Arbeit gibt einen kurzen überblick über die neueren Entwicklungen auf dem Gebiet der
tierexperimentell-immunologischen Traumaforschung und geht eingehend auf den aktuellen Stand der klinisch-immunologischen
Traumaforschung ein. Insbesondere wird die Bedeutung der sog. pro- und antiinflammatorischen Cytokine bei der Entstehung von
SIRS, MOF und ROF er?rtert. Trotz der vielen Fortschritte auf dem Gebiet der klinischen Immunologie und der vielf?ltigen Informationen
über die Trauma-induzierten Immunfunktionsst?rungen müssen jedoch noch viele offene Fragen gel?st werden, bevor die immunologischen
Ver?nderungen nach schwerem Trauma durch immunmodulatorische Therapieans?tze nachhaltig positiv beeinflu?t werden k?nnen.
相似文献
5.
Reich SM Wichmann M Frankenberger R Zajc D 《Journal of biomedical materials research. Part B, Applied biomaterials》2005,74(2):740-746
The aim of this study was to evaluate the shear bond strength of three resin cements to Vita Mark II ceramics under different pretreatments of the ceramic surface and to examine whether simplified pretreatment procedures would result in satisfying results compared to the state of the art. RelyX Unicem (RXU), Calibra (CAL), and Variolink II (VAR) were used as resin cements and bonded to machine milled feldspatic disks, pretreated in five different ways. (1) no pretreatment of the ceramic surface; (2) surface etched with hydrofluoric acid (HF); (3) ceramic surface silanized; (4) ceramic surface etched (HF) and silanized, (5) ceramic surface etched (HF), silanized, and covered with Heliobond. The shear bond strengths were measured initially, after 5000 and 10,000 thermocycles (TC). After 10,000 TC for CAL only procedure 5 resulted in a reliable adhesion median value of 10.7 MPa. VAR showed median values of 24.6, 17.2, and 18.1 MPa for pretreatments 5, 3, and 4, respectively. RXU performed 25.9, 22.0, and 11.0 MPa for procedures 5, 4, and 3, respectively. For procedure 2, RXU revealed the significantly highest value with 15.4 MPa (U-test, p = 0.05). Only RXU-luted specimens of procedure 1 survived the 10,000 thermocycles. The results revealed that a simplification of the ceramic pretreatment for VAR and RXU might be possible. 相似文献
6.
T. Weitzel O. Wichmann N. Mühlberger B. Reuter H-D. Hoof T. Jelinek 《Clinical microbiology and infection》2006,12(9):921-924
Data concerning the clinical and epidemiological features of travel-associated cryptosporidiosis are lacking. In order to investigate the impact of this disease on travellers' health, a retrospective study was conducted at the Institute of Tropical Medicine, Berlin. In total, 57 cryptosporidial infections were identified between 2000 and 2004, resulting in a prevalence of 2.9% in patients with travel-associated diarrhoea. Travel to south-central Asia, especially India, was associated with a higher prevalence of infection than was travel to other destinations. Clinically, the disease resembled giardiasis, but fever and arthralgias seemed to occur more frequently. 相似文献
7.
T cell reactivity in neonates from an East and a West German city--results of the LISA study 总被引:1,自引:0,他引:1
Lehmann I Thoelke A Weiss M Schlink U Schulz R Diez U Sierig G Emmrich F Jacob B Belcredi P Bolte G Heinrich J Herbarth O Wichmann HE Borte M 《Allergy》2002,57(2):129-136
BACKGROUND: Within an ongoing birth cohort study (LISA) the cytokine production of cord blood T cells was compared between neonates from Leipzig (East Germany) and Munich (West Germany). The aim of this study was to analyse regional differences and influencing factors of the immune status. METHODS: Cytokine production was measured in a randomly selected subgroup of 158 children from the LISA (Life style - Immune system - Allergy) cohort by intracellular cytokine staining. Information on family "atopy" history (FAH) and home characteristics was obtained from questionnaires. RESULTS: Reduced numbers of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) producing T cells were found in association with biparental FAH and housing renovation during pregnancy. In addition, cytokine production was influenced by season. In Munich, the frequency of biparental FAH and of renovation measures during pregnancy was significantly higher as compared to Leipzig. Neonates from Munich showed significantly decreased amounts of IFN-gamma and TNF-alpha and elevated levels of interleukin-4 (IL-4) producing T cells. Differences in cytokine production between Munich and Leipzig were influenced by season (IL-4) and housing renovation (IFN-gamma, TNF-alpha). CONCLUSIONS: Since differences in the T cell cytokine production of neonates in Munich and Leipzig are independent from FAH our findings may provide evidence for the impact of environmental factors upon the fetal immune system. 相似文献
8.
Gehring U Brunekreef B Fahlbusch B Wichmann HE Heinrich J;INGA Study Group 《Allergy》2005,60(8):1079-1082
BACKGROUND: Moisture is vitally important for house dust mites and they cannot survive in cold or hot-dry climates. AIMS OF THE STUDY: To investigate the influence of two extraordinarily cold and dry winters in 1995/1996 and 1996/1997 on house dust mite levels in German homes. METHODS: Dust samples were collected between June 1995 and December 2001 on the mattresses of 655 adults and 454 schoolchildren living in five different areas of Germany. We compared house dust mite allergen Dermatophagoides pteronyssinus (Der p 1) levels before and during the winters of 1995/1996 and 1996/1997 with levels after these winters. RESULTS: D. pteronyssinus (Der p 1) levels in samples taken after the cold winters of 1995/1996 and 1996/1997 were approximately two times lower than Der p 1 levels in dust samples collected before or during these respective winters (Geometric means: Erfurt 89 vs 33 ng/g; Hamburg 333 vs 219 ng/g; Bitterfeld, Hettstedt, and Zerbst 296 vs 180 ng/g). Except for Hamburg, the decrease in Der p 1 levels was statistically significant. D. pteronyssinus levels measured in dust samples collected in 2001 (i.e. 3 years after the two cold winters) show a statistically non-significant increase (Geometric means: Erfurt 33 vs 39 ng/g; Hamburg 219 vs 317 ng/g), suggesting that it may take a long time for mite allergen levels to increase again after a sudden decrease. CONCLUSION: We conclude that Der p 1 levels in German mattress dust samples have been approximately reduced by a factor of three to four by the two consecutive cold winters of 1995/1996 and 1996/1997. 相似文献
9.
Lung cancer risk in male workers occupationally exposed to diesel motor emissions in Germany. 总被引:4,自引:0,他引:4
I Brüske-Hohlfeld M M?hner W Ahrens H Pohlabeln J Heinrich M Kreuzer K H J?ckel H E Wichmann 《American journal of industrial medicine》1999,36(4):405-414
BACKGROUND: Although in several epidemiological studies exposure to diesel motor emissions (DME) shows an elevated lung cancer risk, it is still controversial whether DME is a human carcinogen. METHODS: In a pooled analysis of two case-control studies on lung cancer in Germany a total of 3498 male cases with histologically or cytologically ascertained lung cancer and 3541 male population controls were included. Information about lifelong occupational and smoking history was obtained by questionnaire. Drivers of lorries, buses, taxies, diesel locomotives and forklift trucks, bulldozers, graders, excavators, and tractors, were considered as exposed to DME and their cumulative exposure was estimated. All odds ratios were adjusted for smoking and asbestos exposure. RESULTS: The evaluation of lung cancer risk for all jobs with DME-exposure combined showed an odds ratio of OR=1.43 (95%-CI: 1.23-1.67). Most pronounced was the increase in lung cancer risk in heavy equipment operators (OR=2. 31 95%-CI: 1.44-3.70). The risk of tractor drivers increased with length of employment and reached statistical significance for exposures longer than 30 years (OR=6.81, 95%-CI: 1.17-39.51). The group of professional drivers (e.g., trucks, buses, and taxies), showed an increased risk only in West Germany (OR=1.44, 95%-CI: 1. 18-1.76), but not in East Germany (OR=0.83, 95%-CI: 0.60-1.14). DME-exposure in other traffic related jobs (e.g., diesel engine locomotive drivers, switchmen, forklift operators) was associated with an odds ratio of OR=1.53 (95%-CI: 1.04-2.24). CONCLUSIONS: The study provides further evidence that occupational exposure to diesel motor emissions is associated with an increased lung cancer risk. 相似文献
10.
Correction of myopia by implantation of a concave Worst-iris claw lens into phakic eyes 总被引:6,自引:0,他引:6
The Worst-Fechner Biconcave Lens for the correction of myopia in phakic eyes is fixated to the anterior iris. Of the 125 eyes implanted between November 1986 and November 1990, 109 eyes ("core group") had a follow-up period of at least 12 months (mean, 25.0; range, 13 to 51). Sixty-eight of these eyes were reexamined at Giessen University Eye Clinic by an independent investigator using a laser flare cell meter; 23 of the eyes also were examined by iris fluorescence angiography. Seventy-five of the 109 eyes (68.8%) were corrected within 1.00 diopters of the desired refraction, and only 10 eyes (9.2%) deviated more than 2.00 D from the calculated correction. The anatomical results were characterized by good fixation, absence of glaucoma, inflammation, and leak from iris vessels. However, the corneal endothelium was damaged in five eyes by surgical trauma, three resulting in corneal edema. In addition, in five eyes the endothelial density decreased during the follow-up period despite an uncomplicated operation, resulting in corneal edema in one eye. These eyes may have had anterior chambers that were too shallow. 相似文献