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1.
2.
H. Bonél A. Frick H. Sittek A. Heuck M. Steinborn R. G. H. Baumeister M. Reiser 《Der Radiologe》1997,37(10):785-793
Summary
Purpose of this study was to evaluate the diagnostic value of a low field dedicated MRI system in hand and wrist imaging.
All 308 exams of the hand and wrist, that were performed on a low-field dedicated MRI system (Artoscan, Esaote Biomedica,
Italy) in our institution in 1996, and high-field MRI exams performed in addition as part of the diagnostic work-up, were
evaluated and correlated to final operative (n = 64) and histologic (n = 12) reports. 90 % of all low-field MRI scans stated a diagnosis according to clinical suspicion. In 62 % the clinical question
was answered, and in 26 % additional pathologies were identified. An MR-diagnosis completely different from the clinical suspicion
was stated in 2 %. High field exams contributed additional information in 6 of 36 patients. In 3 patients a tumor was not
shown completely in the limited field-of-view of the dedicated low-field MRI-system. Frequency-selective fat-suppression pulse
sequences and a better spatial resolution were the reasons for the additional information obtained in the other three patients.
Low-field dedicated MR-imaging is a valuable method in the extensive work-up of the hand and wrist. Osseous, ligamentous and
tendinous pathologies are well depicted. Large or infiltrative tumors should be referred to a high-field system.
相似文献
3.
Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit
the determination of femtogram amounts of 26Al in blood and in various
tissues with good precision and free of external contamination. METHODS: In
the present study we used trace quantities of 26Al to investigate the
intestinal absorption and compartmentalization of aluminium in rats with
renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single
oral doses of 20 ng 26Al were administered to six animals in each group
and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone,
liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al
were significantly lower in uraemic rats compared to controls, whereas
urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/-
6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in
uraemia. The target tissues of cellular transferrin-mediated 26Al uptake,
liver and spleen, tended to show a larger degree of aluminium accumulation
in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27
pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site
of extracellular aluminium deposition, 26Al concentrations were more
elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g).
Estimated total 26Al accumulation in all measured target tissues was
significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/-
7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/-
6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a
fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our
data suggest that fractional absorption from a dietary level dose of 26Al
is about 0.13%. Compartmentalization occurs in transferrin-dependent target
tissues such as liver and spleen; however, in quantitative terms
extracellular deposition in bone is more important. Uraemia has a
significant effect on the intestinal absorption and compartmentalization of
aluminium. It enhances fractional absorption and increases subsequent
extracellular deposition of aluminium in bone. However, at the same time
uraemia does not increase transferrin-dependent cellular accumulation of
aluminium in liver and spleen.
相似文献
4.
A A Baumeister 《Brain research》1991,557(1-2):136-145
This study examined the effects of bilateral intranigral microinjection of selective opioid agonists on the tail-flick and hot-plate antinociception tests. The principal findings are: (1) the mu-selective agonist D-Ala2, N-Me-Phe4, Gly5-ol-enkephalin (DAGO) had antinociceptive effects on both tests which were reversible by beta-funaltrexamine (beta-FNA: a mu-selective antagonist) and naloxone (a non-selective opioid antagonist); (2) the antinociceptive potency of DAGO injected into the nigra is comparable to its potency in the periaqueductal gray; (3) intranigral D-Pen2, D-Pen5-enkephalin (a delta-selective agonist), U-50, 488H and dynorphin A-(1-13) (kappa-selective agonists) had no antinociceptive effects; (4) antinociceptive effects were produced by the mixed delta/mu agonists D-Thr2-leucine enkephalin-Thr (DTLET) and D-Ser2-leucine enkephalin-Thr (DSLET); (5) the effect of DTLET on the hot-plate but not the tail-flick test was reversed by Cys2, Tyr3, Orn5, Pen7-amide (CTOP; a mu-selective antagonist), beta-FNA, and naloxone, but not by the delta-selective antagonist naltrindole. Based on the potent antinociceptive effects of DAGO, the complete lack of such effects by the highly selective delta and kappa agonists, and the antagonism of DTLET by CTOP and beta-FNA, it is concluded that the antinociceptive effects of intranigral opioid agonists are mediated by mu receptors. 相似文献
5.
Axel Stäbler M.D. Richard G. H. Baumeister M.D. Ulrike Szeimies Ulrich Fink M.D. Hermann Berger M.D. 《Skeletal radiology》1994,23(2):103-106
Post-traumatic ulnar carpal translocation is a rare, severe ligamentous injury to the wrist. Radiologic findings include widening of the radiocarpal joint space at the radial styloid process and ulnar displacement of the carpus. Less than 50% of the lunate articulates with the radius in the neutral position; the lunate is tilted dorsally with palmar subluxation due to a ruptured radioscapholunate (RSL) ligament. This malposition should be called rotatory palmar subluxation of the lunate (RPSL), by analogy to rotatory subluxation of the scaphoid (RSS). In contrast to dorsiflexed intercalated segment instability (DISI), in RPSL the RSL ligament is ruptured and, in the majority of cases, the scapholunate ligament remains intact. A prompt diagnosis should lead to successful treatment. 相似文献
6.
Klaus Hamprecht Matthias Vochem Andrea Baumeister Michael Boniek Christian P Speer Gerhard Jahn 《Journal of virological methods》1998,70(2):167-176
Human cytomegalovirus (HCMV) DNA can be detected in different compartments of human milk. A protocol for the preparation of milk whey free of fat and cells for the detection of human cytomegalovirus (HCMV) by nested PCR is presented. This is based upon the experience of the separation of more than 200 milk specimens of healthy seropositive breast feeding mothers. HCMV DNA could be detected in freshly centrifuged and filtrated milk whey specimens without contamination by cellular DNA. In limiting dilution experiments using HCMV plasmid DNA, the effect of different DNA extraction procedures from native milk and milk whey on the detection limit of cytomegaloviral DNA was demonstrated. About 200 viral genome equivalents/ml in milk whey or native milk were detectable by classical organic phenol/chloroform extraction or a spin column method, respectively. The detection of viral DNA in milk cells depended on a minimum number of milk cells (105–2×105) available for DNA extraction. In contrast to the findings of cytomegaloviral DNA in native sera or plasma of immunosuppressed patients we failed to amplify low level viral DNA from native breast milk by nested PCR due to an inhibition of Taq polymerase by lipid components. Finally, the course of cell associated and cell free DNAlactia was monitored. Analyzing sequential milk specimens, in some cases the presence of HCMV DNA in colostrum could be demonstrated. DNAlactia of milk cells and whey was partially discordant. Onset (week 1–4 after delivery) and duration (2 weeks up to more than 3 months) of DNAlactia showed distinct individual patterns. The methods described, allow further analysis of the mechanisms involved in the postnatal HCMV transmission by breast feeding seropositive mothers. 相似文献
7.
Andrea Verónica Pontoriero Elsa Graciela Baumeister Ana María Campos Vilma Lidia Savy Yi Pu Lin Alan Hay 《Journal of clinical virology》2003,28(2):130-140
BACKGROUND: The analysis of epidemic influenza virus has been focused on antigenic and genomic characterization of the hemagglutinin (HA) glycoprotein in order to detect new variants for the recommendation of the vaccine strains in each season. Since October 1998, WHO organized a second meeting to evaluate the vaccine formula for the southern hemisphere. OBJECTIVES: (a) Present the antigenic and genomic characterization of influenza strains obtained from the Argentina surveillance network, (b) compare between strains collected in Argentina and other countries with the vaccine formula strains used in each season. STUDY DESIGN: Influenza strains were collected during a 5-year period (1995-1999). Initially, laboratory diagnosis was done by immunofluorescence (IF) assay on clinical samples, followed by viral isolation in Madin-Darby canine kidney (MDCK) cells. The isolates were characterized antigenically by hemagglutination-inhibition (HI) assay with post-infection ferret antisera. The genomic characterization consisted on RT-PCR followed by sequencing of the HA1 portion of the HA gene. The comparison between reference and circulating strains was analyzed by the construction of phylogenetic trees. RESULTS: The H3N2 circulating strains matched the corresponding vaccine component only in 1999, the first year when a vaccine recommended specifically for the southern hemisphere was used. Besides, H1N1 circulating strains matched the corresponding vaccine component only in 1998. Regarding to influenza B, only in 1995, the circulating strains showed no match to the B vaccine component. CONCLUSIONS: The results showed the usefulness of an intensified influenza laboratory surveillance to access the correct vaccine and the importance of having the necessary tools to characterize the circulating strains. 相似文献
8.
Schmitz Timo Meisinger Christa Kirchberger Inge Thilo Christian Amann Ute Baumeister Sebastian E. Linseisen Jakob 《European journal of epidemiology》2021,36(6):619-627
European Journal of Epidemiology - The aim of this study was to evaluate the impact of the COVID-19 pandemic lockdown on acute myocardial infarction (AMI) care, and to identify underlying stressors... 相似文献
9.
M. F. El-Khatib B. Baumeister P. G. Smith R. L. Chatburn J. L. Blumer 《Intensive care medicine》1996,22(3):264-268
Objective To evaluate the accuracy of the initial negative inspiratory pressure (PI) to maximal negative inspiratory pressure (PImax) ratio in predicting extubation outcome for intubated infants and children.Design A prospective study. Setting: Pediatric intensive care unit.Patients A sample of 50 stable intubated pediatric patients who were judged clinically ready for extubation.Methods Using a one-way valve,PI andPImax were measured in all patients, after which the ratioPI/PImax was calculated and its accuracy in predicting extubation outcome evaluated.Measurements and results A total of 39 patients (78%) were successfully extubated and 11 patients (22%) were not. The meanPI/PImax ratio was not significantly different between extubation successes (0.36±0.14) and failures (0.45±0.1) (P>0.05). The cut-off value of 0.3 forPI/PImax identified in adult patients did not discriminate between extubation success and failure in children. Furthermore, a discriminatory cut-off value other than 0.3 could not be identified for infants and children.Conclusion ThePI/PImax ratio cannot be used to predict extubation outcome in pediatric patients. Indices that predict extubation outcome in adults should not be extrapolated to infants and children before testing and validation. 相似文献
10.
Prof. Dr. T. Kohnen M. Baumeister M. Cichocki 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2005,102(10):1003-1018
In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss. 相似文献