Search PubMed⌕ Search

Biomedical subjects

B Mayr

Publications and source records attributed to B Mayr.

At least 127 records · Page 7Linked to original sources
PubMed1986

[Computed tomography in endocrine orbitopathy: the effects of varying gantry tilt and patient positioning on the measurement of eye muscle thickness and the possibilities for correction].

Thickening of eye muscles in endocrine orbitopathy can be demonstrated particularly impressively in coronary computed tomograms. However, when measuring the height and width of rectus eye muscles manifesting pathologic changes, the measurement is increased by a deviation from the coronary section plane; this is due to different tilting of the gantry. This often leads to an incorrect stage classification and makes objective observation of the course (e.g., under therapy) impossible. By converting the measured values into the actual extent of the muscles by means of the cosine set, appreciable changes in the pattern and frequency of affection of the rectus eye muscles were found in 121 patients examined.

Adult↗
PubMed1985

Levels of conservation and variation of heterochromatin and nucleolus organizers in the Bovidae.

Chromomycin A3 banding of the mitotic sets of 10 species of Bovidae (cattle, wisent, yak, banteng, gaur, red buffalo, swamp buffalo, sheep, mufflon, and goat) serves to demarcate both centromeric constitutive heterochromatin and R-banding patterns capable of identifying all the chromosomes within a given complement. In all species significant amounts of chromomycin-bright heterochromatin are present at the centromeres of all autosomes, though there was a high degree of intra- and inter-individual variation in the size of the heterochromatic blocks. Marked interspecies differences in the centromeric patterns were evident. The X chromosomes contained appreciable amounts of centromeric heterochromatin only in the two buffaloes. All the animals studied lacked distamycin A - diamidinophenylindole type heterochromatin. AgNO3 staining was applied sequentially to detect the location of active nucleolus organizer regions (NORs). The distribution of NORs was reasonably conservative in most of the species. An exceptional situation was found in the two buffaloes, where only one NOR pair matched with the standard karyotype of the Bovidae.

Animals↗
PubMed1985

A viable calf with trisomy 22.

Karyotyping of eight malformed calves resulted in the detection of trisomy 22 in one calf. This calf had a hernia umbilicalis, a urachus fistula, and slight brachygnathia inferior. This trisomy was not associated with lethality.

Animals↗
PubMed1985

[Value of nuclear magnetic resonance tomography in the diagnosis and therapy outcome of prolactinomas].

30 MR tomographies were performed in 15 patients suspected of having a prolactinoma on account of clinical examinations and test in the chemical laboratory. The T1 and T2 times of the adenomas were determined quantitatively. In addition, high resolution CT imaging had been performed in all patients. The signal performance of the normal pituitary gland determined in 11 healthy persons on the basis of quantitatively measured T1 and T2 times, was found to largely correspond with that of grey matter of the brain. Of the 14 confirmed prolactinomas, 11 were microadenomas and 3 macroadenoma. Solid adenomas were identified by enhanced T1 values. It was possible to differentiate these from cystic, haemorrhagic and necrotic tumour components by differences in signal performance. 7 patients on drug therapy with dopamine agonists were controlled by means of MR tomography. No measurable size reduction of tumour was seen in 3 patients with cystic or haemorrhagic tumour components. On the other hand, tumour reduction was seen after brief drug therapy in 2 macroprolactinomas and one microprolactinoma. An essential advantage offered by MR is, besides the absence of exposure to radiation, in the first place the better and more precise information on the relative position of the adenoma with reference to the vessels and the optic chiasm, and, secondly, better identification of cystic and haemorrhagic processes within the prolactinoma.

Adenoma↗
PubMed1984

[Bleomycin-induced pulmonary infiltrations in the treatment of testicular cancer].

Under Cisplatinum/Vinblastine/Bleomycin treatment six of 82 patients with nonseminomatous testicular cancer developed a Bleomycin-induced pulmonary toxicity. After a total Bleomycin dose of 300-360 mg all six patients showed multiple nodular densities near the pleura in the basal lung areas on the computed tomographic scanning (CT). Disseminated interstitial infiltrates, mostly in the lower lung fields were spontaneously observed by means of chest X-rays in only one case. In two other cases only minimal changes were found retrospectively. In five cases the diffusion capacity did not decrease significantly. Diffusion capacity, vital capacity and oxygen fell significantly in only one case. The latter was also the only patient showing clinical symptoms. The lung changes were completely reversible in four patients 4-6 months after cessation of Bleomycin. In two patients there were reversible residual changes after a timespan of 20 and 24 months. Two patients received no further antineoplastic treatment, two were under maintenance therapy, two under further induction chemotherapy because of the assumption of lung metastases. None of the six patients show any evidence at present of testis tumor (observation period 17-34 months). It can be difficult to distinguish between Bleomycin-induced lung damage and tumor metastases by radiological means. We were able to differentiate by observing the clinical course of the six patients. In case of doubt a histological examination is strongly recommended.

Adult↗
PubMed1984

Heterochromatin and nucleolus-organizer-region behaviour at male pachytene of Sus scrofa domestica.

In the domestic pig (2n = 38) two types of constitutive heterochromatin can be differentiated by fluorescence counterstaining techniques. All 24 biarmed autosomes and the X chromosome have chromomycin A3-positive centromeric C-bands, whereas all 12 acrocentric chromosomes exhibit DA-DAPI-positive centromeric heterochromatin. Fluorescence analysis of male pachytene nuclei revealed that the DA-DAPI-positive C-bands form one or two large chromocentres per cell, while the chromomycin A3-bright C-material is well scattered. Hence, the bivalents formed by the acrocentric chromosome pairs are centromerically associated, whilst the submetacentric bivalents are not. Counce-Meyer spreading techniques were used to study the structure of synaptonemal complexes (SCs) both by light and electron microscopy. In general, the SCs of the domestic pig resemble those described for other mammals. The SC formed by the X and the Y may include up to 94.5% of the Y chromosome. In silver-stained microspreads each of the bivalents (nos. 8 and 10) bearing the nucleolus-organizer-regions (NORs) is connected to a pair of nucleoli, indicating that all four NORs are active during early meiotic stages. By contrast, in the majority of mitotic metaphases of phytohaemagglutinin-stimulated lymphocytes only one pair (no. 10) exhibited Ag-NOR staining. The significance of the chromosome disposition in the pachytene nucleus is discussed with regard to heterochromatin composition and karyotype evolution.

Animals↗
PubMed1984

[Differential diagnostic problem of distinguishing pulmonary infiltrates following bleomycin therapy from metastases].

Sixty patients with malignant testicular tumours were treated with bleomycin according to the Einhorn regime. Following treatment, pulmonary infiltrates were seen on the chest x-ray of three patients and the CT of six patients. Altogether 24 infiltrates resembling metastases were seen in five patients. Five round foci were combined with infiltrates in other parts of the lung. Regression of the infiltrates after stopping bleomycin, negative tumour markers, the timing of the development of the infiltrates and the regression of the infiltrates in three patients without treatment make it extremely unlikely that the appearances were due to metastases.

Adult↗
PubMed1984

Karyotyping, red blood cell and haemoglobin typing of the mithun (Bos frontalis), its wild ancestor and its hybrids.

In Bhutan in remote parts of the Himalayas the mithun (Bos frontalis) has been used probably for centuries in an ingenious system for crossbreeding with domestic cattle which results in highly profitable hybrid females. The hybrid males are infertile and so far no stable crossbreed has been developed. Genetic analyses reported in this paper support the view that the gaur is the wild ancestor of the mithun. Both have only 58 chromosomes in contrast to 60 in cattle and also different, hitherto undescribed haemoglobins and blood groups which would justify the revision of the present classification of the subfamily Bovinae. If, with the aid of modern genetic methods, a stable crossbreed could be developed, dairy and beef production in Bhutan and many climatically similar areas could benefit greatly. Because of its remarkable size the mithun may, in the hands of enterprising breeders, also make a useful genetic contribution to beef production elsewhere.

Animals↗
PubMed1983

Characterization of the canine karyotype by counterstain-enhanced chromosome banding.

The application of the counterstain-contrasted fluorescent banding technique to canine chromosomes provided an improved capability to highlight specific heterochromatic regions and to produce well defined banding patterns both on mitotic and meiotic chromosomes. Triple staining with chromomycin A3 - distamycin A - DAPI revealed the occurrence of DA - DAPI positive heterochromatin in chromosomes 33, 36, 37, and 38. Pachytene nuclei present more favourable material for the detection of very small amounts of DA - DAPI material than mitotic division stages. Counterstain-enhanced chromomycin R-banding greatly facilitated chromosome identification. A standard R-band karyotype of Canis familiaris is proposed and described in some detail. DAPI - actinomycin D staining produced a QFH-type banding pattern and enhanced differentiation of some polymorphic regions.

Animals↗
PubMed1983

[Comparison of conventional radiology, ultrasound and computer tomography in the preoperative localization of intraocular foreign bodies].

Three methods complementing each other are available for the preoperative intraocular localisation of foreign bodies. Basing on the results obtained, it is recommended, first of all, to localise the site of the foreign body by means of conventional x-ray film, followed by fine diagnosis via ultrasound and, finally, in problematic or doubtful cases, by means of computed tomography.

Diagnosis, Differential↗
PubMed1983

[Results of serial CT in the evaluation of the sellar region].

The article reports on the methodology and results of serial CT in differential diagnosis of intrasellar and parasellar structures, based on 32 examinations. Whereas the normal pituitary gland displays an approximately equal contrast medium performance as the pituitary adenomas and recurrent tumours, different types of tissue such as those of tumours, vascular structures and postoperative scans can be well differentiated from each other by means of serial CT. Aneurysms can be safely differentiated from intracranial tumours, such as meningiomas, only via serial CT.

Adenoma↗
PubMed1983

[Computer tomography evaluation of tumor-induced bladder wall changes].

25 patients in whom a carcinoma of the urinary bladder had been confirmed, were examined preoperatively by means of computerised tomography, and the local size of the tumour was determined. These findings were compared postoperatively with the histopathological staging. The degree of tumour spread was verified exclusively via cystectomy. CT does not yield very relevant data in respect of the therapeutically important differentiation of the low tumour stages. However, CT is very well suited in the diagnosis of tumours which have penetrated the bladder wall; however, diagnostic relevance in respect of organ infiltration can be definitely limited by the overlapping of other organs.

Carcinoma, Transitional Cell↗
PubMed1982

Circulating immune cells and immune complexes in peripheral blood of healthy and of bovine leukemia virus-infected cows and lymphosarcomatous calves.

The peripheral blood (lymphocytes and immune complexes (IC) from 20 healthy cows, 5 healthy calves, 10 bovine leukemia virus-infected cows and 4 lymphosarcomatous calves was investigated using 4 different immunological techniques. A highly significant increase in the percentage of surface immunoglobulin (SIg)-bearing peripheral blood lymphocytes of persistent lymphocytosis-cows could be demonstrated while the percentage was decreased in the lymphosarcomatous calves. Percentages of spontaneous sheep red blood cells(SRBC)-rosettes (E-rosettes) were not elevated. Antibodies to bovine leukemia virus-antigen were detected in the sera (immuno-diffusion test) of all the leukotic cows but not of the lymphosarcomatous calves. Although there seems to be an increased level of IC in the advanced stage, as compared to the beginning of the disease, there was no statistically significant difference in comparison with the control individuals. In the lymphosarcomatous calves as well as in the leukemic cows there was no statistical difference in the IC values between diseased animals and controls.

Animals↗