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Biomedical subjects

K J Schmidt

Publications and source records attributed to K J Schmidt.

At least 19 recordsLinked to original sources
PubMed2004

UV Raman spectroscopy of hydrocarbons.

In this paper, the UV Raman spectra of a large number of saturated and alkyl-substituted monocyclic, bicyclic and polycyclic aromatic hydrocarbons are obtained at 220 and 233 nm excitation wavelengths. Also included are nitrogen- and sulphur-containing hydrocarbons. The spectra obtained are fluorescence free, even for such highly fluorescent compounds as perylene, consistent with earlier reports of UV Raman spectra of hydrocarbons. The hydrocarbon UV Raman spectra exhibit greatly improved signal-to-noise ratio when in the neat liquid or solution state compared with the neat solid state, suggesting that some surface degradation occurs under the conditions used here. Assignments are given for most of the bands and clear marker bands for the different classes of hydrocarbons are readily observable, although their relative intensities vary greatly. These results are discussed in the context of structure and symmetry to develop a consistent, molecular-based model of vibrational group frequencies.

Hydrocarbons↗
PubMed2000

Comparison of nickel-titanium and stainless-steel spreader penetration and accessory cone fit in curved canals.

The purpose of this study was to compare nickel-titanium and stainless-steel spreader penetration in curved canals. Twenty prepared plastic blocks with a 30 degrees curvature were used for each part of the study. In part 1, the force required to insert each spreader to within 1 mm of working length in an empty canal was measured. In part 2, the force required to insert each spreader to within 3 mm of working length was measured in a canal containing a master cone. In part 3, the depth of penetration of each spreader with a master cone in place using a 1.5 kg force was measured. Additionally, in part 3, the depth of penetration of the first accessory cone was measured. The results from part 1 showed that a nickel-titanium spreader required significantly less force than a stainless-steel spreader (0.30 kg vs. 0.59 kg). In part 2, a nickel-titanium spreader required significantly less force than a stainless-steel spreader (1.56 kg vs. 2.42 kg). In part 3, a nickel-titanium spreader penetrated significantly deeper than a stainless-steel spreader (15.0 mm vs. 14.0 mm). There was no significant difference in the depth of penetration of the first accessory cone used after either spreader (0.8 mm vs. 0.7 mm). Therefore, the potential for vertical root fracture in curved canals during lateral condensation may be minimized by using nickel-titanium spreaders.

Dental Instruments↗
PubMed1999

UV stimulation of chromosomal marker exchange in Sulfolobus acidocaldarius: implications for DNA repair, conjugation and homologous recombination at extremely high temperatures.

The hyperthermophilic archaeon Sulfolobus acidocaldarius exchanges and recombines chromosomal markers by a conjugational mechanism, and the overall yield of recombinants is greatly increased by previous exposure to UV light. This stimulation was studied in an effort to clarify its mechanism and that of marker exchange itself. A variety of experiments failed to identify a significant effect of UV irradiation on the frequency of cell pairing, indicating that subsequent steps are primarily affected, i.e., transfer of DNA between cells or homologous recombination. The UV-induced stimulation decayed rather quickly in parental cells during preincubation at 75 degrees, and the rate of decay depended on the incubation temperature. Preincubation at 75 degrees decreased the yield of recombinants neither from unirradiated parental cells nor from parental suspensions subsequently irradiated. We interpret these results as evidence that marker exchange is stimulated by recombinogenic DNA lesions formed as intermediates in the process of repairing UV photoproducts in the S. acidocaldarius chromosome.

Conjugation, Genetic↗
PubMed1997

[Development of treatment guidelines and procedure guidelines within the scope of developing case fees and a modular quality management system (MQM)].

Since 1991 Diagnostic Related Groups (DRGs) are systematically developed for standardized operation procedures. They are included in a Quality Management System of the DIN EN ISO 9001 ff. norm and are part of the process system. In additional the internal and external evaluation of quality completes a Modular Quality Management System (MQM). These procedures meet the requirements for a Total Quality Management (TQM).

Algorithms↗
PubMed1996

[Introduction of quality circles and a quality management system (QMS) in a centralized clinic].

At our hospital, a quality management system was developed according to the DIN EN ISO 9001. Additionally, several quality circles and an external quality control system with three tracer diagnoses were carried out and two studies were performed to detect the internal and external acceptance of the hospital. All strategies induce an increase in the quality of management and of the patients' outcome.

Cholecystitis↗
PubMed1980

[Aetiological treatment of benign goitre with l-thyroxine (author's transl)].

L-Thyroxine was given to 3956 patients with benign goitre between 1974 and 1977, 2314 of which were controlled over a period of 3 years at regular intervals. Benign goitre in children less than 14 years old and postoperative recurrences were not evaluated. Definite reduction in goitre size wss achieved in 77.2% of patients by continuous long-term treatment over 3 years. In large goitres and those with nodular transformation the status quo was maintained in all but exceptional cases.

Female↗
PubMed1976

[Mechanical and functional complications in endemic struma (author's transl)].

Of 1294 patients examined with struma of magnitude I to III, complications in the form of mechanical effects on the neighboring organs, disturbances of thyroid function and pathological anatomical changes in the struma were demonstrated in 1051 cases. The appearance of high-seated esophageal varices is described in 33 patients with primary struma of magnitude II and III. 72 patients had congenital or postnatal hypothyroidism, and 164 patients a subclinical one. The carcinoma ratio (2.9%) was in the lower range of the normal for the endemic areas. Because of the high complication rate, every struma should be clarified diagnostically and specifically treated.

Adenocarcinoma, Papillary↗
PubMed1975

Competitive protein binding radioassay of plasma and urinary unconjugated cortisol.

In order to establish a more reliable profile of the function of the adrenal cortex, a study has been made of this simultaneous estimation of plasma and urinary unconjugated cortisol by competitive protein binding (CPB) radioassay. Both plasma and urinary cortisol were measured by CPB radioassay after solvent extraction. Normal ranges were found for plasma and urinary cortisol. The samples obtained in the morning (8:00 am) established a normal plasma cortisol range of 9.0-21.6 mug% with a mean of 15.3. range for urinary unconjugated cortisol was 12.0-41.5 mug/day (mean 26.9). Dexamethasone suppression and adrenocorticotrophic hormone stimulation of plasma and urinary cortisol were tested with individuals having normal and abnormal adrenal cortical function. RESULTS INDICATED A GOOD CLINICOPATHOLOGICAL CORRELATION. It was concluded that plasma and urinary unconjugated cortisol are reliable laboratory tests for adrenocortical function and would be the methods of choice rather than urinary 17-ketogenic steroids.

17-Ketosteroids↗