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901.
There were repeated histological bioptic examinations of the endometrium during the period from the second to twentieth day post partum (p.p.) in cows with afterbirth retention (n = 5), with developing puerperal endometritis (n = 5), and with a physiological course of puerperium (n = 5). In cows with a physiological course of puerperium, a finished process of epithelization of endometrium with a morphological and functional consolidation of the epithelium could be observed on the 20th day p.p. In cows with disturbed puerperium, the surface epithelium still exhibited signs of disintegration and a low secretion activity. The endometria of both groups of cows with pathological puerperium had a high degree of infiltration with neutrophil granulocytes: in cows with retained afterbirth this picture was characteristic already the second day p.p. On the other hand, the endometrium of cows with physiological puerperium was characterized by a higher occurrence of folliculoid nodules as early as on the tenth day p.p., and a rapid increase in the number of fat cells and activated histiocytes--macrophages could be observed in the endometrium of these cows between the 15th and 20th day p.p. The dynamics of occurrence of mobile cells in the studied groups of cows confirmed their importance for a physiological course of the restitution of endometrium during the puerperium of cows. 相似文献
902.
S. E. Zorinyants A. V. Nosov E. D. Badaeva I. N. Smolenskaya N. S. Badaev 《Plant Breeding》1995,114(3):219-225
In vitro culturing of plant cells can cause changes in karyotype. Chromosome variations following long-term propagation in suspension culture of Triticum timopheevii (Zhuk.) Zhuk. were studied by routine staining and C-banding. The culture was highly heterogeneous with respect to the number and structure of chromosomes. The modal class cells had a lower chromosome number than T. timopheevii (2n= 28). This data was confirmed by cytophotometric analysis of nuclear-DNA content. Frequencies of chromosome loss varied for different homoeologous groups. At genome chromosomes tended to be preferentially eliminated in cells of different ploidy levels. Deletions, insertions, translocations, telocentric chromosomes, isochromosomes and dicentrics and their derivatives were observed in cultured cells. Chromosomes of various homoeologous groups differed in the frequencies and spectra of re—arrangements, but most aberrations occurred in the G-genome chromosomes. In vitro chromosome modifications did not correspond to in vivo variation. Presumably, this difference was caused by differences in the mechanisms of adaptation to the environment at the levels of the cell and the whole organism. G-genome chromosomes were more frequently involved in this process, both in vivo and in vitro. 相似文献
903.
R. Tippkötter 《Geoderma》1983,29(4):355-371
Twenty oriented blocks, roughly 10 cm along each edge, were collected from the Bv and C horizons of four Hapludalfs near Hannover (West Germany). At least two blocks were obtained from each horizon of each profile. The macropores (0.1–1 mm) in these blocks were then examined by micromorphological methods. The 3-dimensional arrangements of pores were observed by two approaches, viz., (1) preparing photographic sequences of successive polished sections obtained from the sample blocks and then stacking photographs to simulate pore geometry; (2) preparing resin casts of tubular pores.Examination of stacked photographs and the resin casts by scanning electron microscopy (SEM) followed by electron-optical image analyses indicate interconnected systems of pores with the most frequently occurring diameters between 150 and 250 μm. Interconnections among pores are very similar in numbers throughout the Bv horizons.Comparisons of the diameters, branching, and tapering of macropores with similar features of plant roots suggest that most pores between 0.1 and 1 mm have been produced by roots. Some may be due to fauna, but all seem to have been of biological origin and are therefore considered biopores. 相似文献
904.
Canine juvenile-onset insulin-dependent diabetes mellitus is a rare disease. While pancreatic acinar atrophy is a well known picture in the dog, the simultaneous occurrence with an endocrine insufficiency has never been clearly established. The clinical, pathological and immunohistochemical findings of a three-month-old German shepherd dog with insulin-dependent diabetes mellitus concurrent with exocrine pancreatic insufficiency are described. 相似文献
905.
906.
Zollinger-Ellison syndrome and myelofibrosis in a dog 总被引:1,自引:0,他引:1
R V English E B Breitschwerdt C B Grindem D E Thrall L A Gainsburg 《Journal of the American Veterinary Medical Association》1988,192(10):1430-1434
Zollinger-Ellison syndrome and myelofibrosis were diagnosed concurrently in a 10-year-old neutered female Brittany Spaniel. Documentation of gastric ulceration, hypergastrinemia, and gastrin-secreting islet cell tumor with splenic metastases facilitated the diagnosis of Zollinger-Ellison syndrome. Patchy long-bone medullary sclerosis, nonregenerative anemia and thrombocytopenia, multiple acellular bone marrow aspirates, marked splenic extramedullary hematopoiesis, and acellular core bone marrow biopsy with areas of necrosis and fibrosis supported the diagnosis of myelofibrosis. Despite the medical and surgical management attempted, the dog was euthanatized because of signs of severe intractable bone pain. Myelofibrosis has been documented in association with canine and human neoplastic disease. A direct causal relationship between gastrinoma and myelofibrosis was not clearly established in this instance. 相似文献
907.
908.
909.
910.
Teratogenic effects of methylparathion / Wofatox 50 EC/ and Parathion 20 WP as positive control material were tested in pheasant embryos. On the 12th day of incubation 0.1 ml of the emulsions or suspensions of the insecticides at different concentrations was inoculated into the air space of embryonated eggs. The following dose levels were employed: 27 and 270 mg/kg egg of Wofatox 50 EC, and 10 mg/kg of Parathion 20 WP. Morphological changes were evaluated by macroscopic, skeletal staining and light microscopic examinations of the embryos. Primary hypoplasia or atrophy developed in the cervical musculature /m. longus colli/ accompanied by lordosis and scoliosis of the cervical spine. In most cases we also found cyllosis . 相似文献