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M Noack

Publications and source records attributed to M Noack.

At least 19 recordsLinked to original sources
PubMed2001

[Functional capacity of MRI-compatible biopsy needles in comparison with ferromagnetic biopsy needles. In vitro studies].

PURPOSE: Comparative evaluation of specimens obtained with different MR-compatible biopsy systems and a conventional ferromagnetic system. METHODS: Biopsies of a pig liver were performed post-mortem with three different MR-compatible (Somatex; E-Z-EM; Daum) and one conventional biopsy system (Somatex), five with each device. The specimens were measured and the histopathological quality was graded on a scale from 0 (no tissue) to 9 (best). The tip of the needle was examined with an electron microscope before and after biopsy to demonstrate abrasion. RESULTS: The histopathological score between the first and fifth specimen taken with one biopsy device showed no significant difference. The conventional system yielded significantly better results in nearly all categories (p < 0.05) than the MR-compatible biopsy systems. The areas of the specimens obtained with the MR-compatible biopsy systems (4.27-5.99 mm2) were significantly smaller than those from the conventional system (9.98 mm2). The needle tip abrasion of the different biopsy systems determined by electron microscopy showed no substantial difference. CONCLUSION: Specimens obtained with MR-compatible biopsy systems compared to conventional biopsy systems are of lower histopathological quality. This might be caused by a smaller side notch of the MR-compatible biopsy devices. There was no difference in abrasion of the needle tip due to the softer, non-ferromagnetic alloys.

Animals↗
PubMed2000

Optimized enhancement in helical CT: experiences with a real-time bolus tracking system in 628 patients.

AIMS: Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. MATERIALS AND METHODS: In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. RESULTS: There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). CONCLUSION: Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration.

Abdominal Neoplasms↗
PubMed1993

Inlays and onlays.

Dentists must meet the increased demands of patients for esthetic dentistry. Because the substitution of amalgam with direct composite restorations is somewhat problematic and restricted to special indications only, the most suitable method is the esthetic inlay. All available systems are reviewed and described. These restorations must be inserted with adhesive techniques. The performance and the problems associated with these techniques are described in detail. Improvements in luting techniques, eg, the use of ultrasonic energy, may further simplify the application technique for esthetic inlays. For clinical success, the margin quality of adhesively luted inlays is essential. In vitro and in vivo studies with esthetic inlays report good clinical behavior of such restorations. However, until the results of long-term clinical studies are available, these systems should not be used on a routine basis as a substitute for amalgam.

Composite Resins↗
PubMed1992

Effectiveness of cefetamet pivoxil in the treatment of pyelonephritis in children.

Cefetamet pivoxil was investigated in an open, randomized comparative study involving a total of 37 children with acute pyelonephritis, whose ages ranged from 2 to 14 years. The patients received either 10 mg/kg (n = 18) or 20 mg/kg (n = 8) cefetamet pivoxil twice daily, or 30-50 mg/kg amoxycillin/clavulanic acid three times daily (n = 11) for a period of 7-10 days. Escherichia coli was the main causative agent isolated in 28 (75.7%) of the patients; other pathogens included Proteus mirabilis (three patients). Proteus species (one patient), Klebsiella pneumoniae (two patients), Pseudomonas diminuta (one patient) and mixed infections (three patients). No differences in the overall treatment outcome could be observed between the treatment regimens used and, at the end of treatment, all pathogens were eradicated with neither relapse, nor persistence of the isolated pathogen, nor reinfection occurring. The clinical signs and symptoms had subsided in all patients at treatment end and the tolerability of the trial drugs was found to be satisfactory with no premature treatment withdrawal required. It is concluded that cefetamet pivoxil in the standard twice-daily dose of 10 mg/kg was equally effective and as well tolerated as 20 mg/kg cefetamet pivoxil given twice daily or 30-50 mg/kg amoxycillin/clavulanic acid given three times daily.

Acute Disease↗
PubMed1990

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy.

A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) to attenuate neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. We treated 22 patients with various solid tumors and lymphoid neoplasias with a single daily subcutaneous dose of GM-CSF (250 micrograms/m2) 48 h after a second cycle of highly myelotoxic chemotherapy for a period of 10 days and compared intraindividually neutropenia-related clinical and laboratory variables with data obtained from the same patients having previously received a first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. We show that GM-CSF is active in neutropenic patients by significantly increasing the neutrophil nadir, reducing the time of relevant neutropenia, and reducing the duration of the patient's hospital stay and necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment.

Agranulocytosis↗
PubMed1990

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy.

PURPOSE: A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human (rh) granulocyte-macrophage colony-stimulating (GM-CSF) factor in attenuating neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. PATIENTS AND METHODS: Twenty-two patients with various solid tumors and lymphoid neoplasias were treated with a single daily subcutaneous dose of rh GM-CSF (250 micrograms/m2) 48 hours after receiving a second cycle of highly myelotoxic chemotherapy for a period of 10 days. Within-subject comparisons on neutropenia-related clinical and laboratory variables were made with data obtained from the same patients after they received the first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. RESULTS: GM-CSF was active in neutropenic patients because it significantly increased the neutrophilic nadir, reduced the time of relevant neutropenia, and reduced the duration of a patient's hospital stay and the necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment. CONCLUSION: Although GM-CSF was shown to significantly reduce chemotherapy-associated morbidity in patients receiving myelotoxic cancer chemotherapy, additional studies are needed to assess whether the use of GM-CSF in anticancer chemotherapy will allow an increase in the dosage level, leading to improved response rates and survival among cancer patients.

Adolescent↗
PubMed1989

Quantitative margin analysis in the scanning electron microscope.

Interface between restorative materials and tooth hard substances must be morphologically as perfect as possible to avoid plaque accumulation and subsequent secondary caries or pulpal diseases. Therefore the marginal behavior of restorations is an important parameter to predict their longevity. Morphologically, the quality of margins is characterized by different well defined criteria. Using a replica technique it is possible to assess the complete marginal circumference of restorations in the SEM. Margins of restorations show a large variety of their morphology. This publication describes a method to quantify the quality of dental restorations. The restoration margins are traced on the SEM screen with a digitizer and an interface to measure the margin's length. Simultaneously the margin quality is assessed and assigned to the corresponding lengths. The % distribution of the quality criteria for each restoration is then calculated. Using a comparative light microscope, the replicas are aligned and mounted identically in the SEM for longitudinal studies. The results presented are limited to tests for the accuracy of the method. Using 5 criteria to characterize the margin quality, it was found that the difference between two measurements by the same operator, 4 weeks apart was 3% +/- 2.6%. The largest difference for one group was 9%. In another accuracy test where 4 criteria for margin characterization were used, the difference between two measurements was 1.9% +/- 0.9%. The largest difference between two groups found was 3.4%. This method can be used for longitudinal studies in vivo, but also for in vitro screening tests with new materials.

Dental Restoration, Permanent↗
PubMed1982

[Effect of DL-tryptophan on photic evoked potentials and basic activity of the EEG].

The effects of DL-tryptophan on photic evoked potentials (photic after discharges--PhNE, photic recruitment--PhR, photic evoked primary potential--PhEP) and basic activity of EEG were investigated in freely moving rats with chronically implanted electrodes in various areas of cortex. DL-tryptophan increased the number of PhNE potentials and particularly the number of NE potentials per answered lightflashes (NE/bLB). The effects depend on dosage of DL-tryptophan. The double impulse stimulation confirmed these results. The power spectral show an increased synchronization of the background EEG activity. The results are discussed in connection with local serotoninergic effects and influences on vigilance by 5-hydroxytryptamine.

Animals↗
PubMed1980

A new immunoenzyme tracer for localization of antibodies in immunohistology: peroxidase-labeled protein A.

Protein A from Staphylococcus aureus, characterized by high affinity binding properties for IgG-type antibodies, was labeled with peroxidase to form a stable immuno-histological tracer molecule of comparatively low molecular weight. It has been used for demonstration of antibodies against tissue antigens, in direct and indirect techniques, and the findings were consistent with those in routine immunofluorescence and in staining with peroxidase-coupled anti-IgG. In comparison, the lowest unspecific tissue adsorption and staining was obtained with Protein A-peroxidase in buffer containing glucose and mannose. The immunohistological preparations were mounted and stored for documentation without apparent loss of staining.

Animals↗
PubMed1979

Lymphocyte response to mitogens in patients with malignant melanoma.

Lymphocyte blast transformation of 23 melanoma patients was compared to that of 22 healthy persons after stimulation with the mitogens PHA, ConA, and PWM. Transformation rate of lymphocytes in microcultures was measured following 3H-Thymidin uptake in a Liquid-Scintillation-Counter. Calculations were based on analyses of variance. There was no significant difference in blastogenetic response between the 2 groups (patients and controls), but there were differences between the used mitogens.

Adolescent↗