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21.
In the period of 3 years, 9 tumours of chemodectoma were supravitally diagnosed and histopathologically verified in dogs. In this period 15 351 dogs were admitted to the Clinic of Dogs and Cats and 2 145 dogs were examined in the cardiological outpatient clinic for dogs. This tumour is located in a typical place - at the base of the heart. Most frequently the tumour manifested in older boxers. Only in one case such a tumour was diagnosed in another breed of dogs. The tumours ranged in size between 3 and 16 cm in diameter. The principal sign accompanying tumours of cardiac base involved dyspnoea but in 3 cases the tumours yielded no clinical signs. All the diagnoses were additionally verified using immunohistochemical examination. We used antibodies to chromogranin A (clone DAK-A3 1:100), synaptophysin (clone SY38 1:20) and neuron-specific enolase (clone BBS/NC/VI-H14 1:150). An immunohistochemical examination is vital for the diagnosis since it allows to differentiate histologically distinct types of neoplasia which may locate in the same site and may manifest a similar histological pattern.  相似文献   
22.
Thaumatococcus daniellii is a perennial African wild edible plant. Fruit arils from natural populations are the source of the protein sweetener, thaumatin. There are relatively few documented examples of its cultivation, however it has great potential as an intercrop for cultivation under rubber or cocoa. Across the species range there is notable diversity in leaf and fruit morphology. In this study, T. daniellii populations from four provenances in Ghana and Cameroon (separated by the Dahomey Gap) were compared for leaf and fruit morphology in situ and in an experiment using plants grown from sampled rhizomes planted under rubber in a single location in Cameroon. When collected rhizomes from four provenances were planted at one location, the samples from the local provenance produced the largest plants and fruits, and there was less morphological variation between samples from different provenances than was recorded in situ. In situ morphological differences were notable between north–south separated provenances in each country. Fruit collected in situ was analysed for aril thaumatin content and significant variation was found between provenances (1.08–2.00%). Amplified fragment length polymorphism (AFLP) was used to assess genetic diversity among the four provenances and 54% of loci were polymorphic. Cluster analysis of AFLP data separated samples of T. daniellii according to geographical origin. Maximum genetic diversity was found between provenances separated across the Dahomey Gap.  相似文献   
23.
The object of the study comprised 54 grass pea (Lathyrus sativus) accessions originating from Czech Republic, Hungary, Slovak Republic, Poland, Ukraine and Russia together with 18 red pea (Lathyrus cicera) accessions from Greece, Spain and Italy. The plants were grown under the same conditions in Poland. Some phenological and morphological traits of plants as well as some seed morphological properties and nutritive value were investigated. Lathyrus sativus seeds contained more protein (average 300?g vs. 255?g?kg?1 dry matter (DM)), whereas the differences in the average contents of the other basic nutrients between both these species as well as between particular accessions were not substantial. Except for a low level of methionine, the protein of both species showed fairly high concentration of other exogenic amino acids (EAAI around 63–64%). Fat of both L. sativus and L. cicera seeds was found to contain a high level of polyunsaturated fatty acids (66.9 and 58.6%, respectively), mainly linoleic (57.4 and 47.2%, respectively). The researched L. sativus accessions had a quite low level of β-ODAP (733?mg with a range of 0.583–1.340?mg?kg?1 DM). Slightly higher content of this ANF (1,168?mg with 911–1,349?mg?kg ?1 DM) in L. cicera seeds was noted. Average tannin concentration in the L. sativus and L. cicera accessions reached 3.3 and 6.4?g?kg?1 DM, respectively. Average content of this ANF in L. sativus significantly correlated with the colour of both, flowers and seeds; with generally, a darker colour associated with higher levels of tannins.  相似文献   
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A hucul mare with reproductive abnormalities was examined during karyotype analysis. The karyotype was analysed based on evaluation of 860 metaphase plates in chromosome preparations. The use of fluorescence in situ hybridization (FISH) with an X chromosome painting probe showed premature X chromosome separation in 9.5% cases of examined chromosome spreads. In this report, we present the first identify premature centromere division (PCD) as a possible cause of abnormal X chromosome morphology in horses and as a probable cause of reproductive difficulties.  相似文献   
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Investigations on I. typographus populations were conducted in 1992–1994 in the Sudeten (south-western Poland), in Norway spruce stands that were devastated previously by insect outbreaks and that exhibited severe forest decline. Crown defoliation and the volume of infested trees per hectare were used as indices of stand health and breeding conditions; variability in the infestation density, gallery length, and body length of beetles were parameters that were used to estimate the response of I. typographus populations to changing stand conditions. In stands located in the zone above 800 m a.s.l. where both the level defoliation and tree mortality were higher, the infestation density and body length of I. typographus were higher than in the zone below 800 m a.s.l., where stands were less damaged. Contrarily, the gallery length was higher in lower montane zone, where lower infestation densities and body length values were found. A proposed mechanism for this interaction, which is attributed mainly to better breeding conditions for I. typographus populations in weakened stands, is presented and discussed.  相似文献   
28.
Forty-five Yersinia enterocolitica strains isolated from aborted fetuses and placentas and from vaginal and rectal swabs of aborting sows were subjected to serotyping, biochemical typing and polymerase chain reaction multiplex analyses to detect the presence of the ail, yst A and ystB genes. The isolates were recovered from the internal organs (tonsil, lung, liver, spleen, kidney, mesentheric lymph nodes, small intestine and rectal intestine) of 18 (18.6%) of 97 aborted fetuses examined, two (8%) of 25 aborted placentas and 27 (15.8%) of 172 examined aborting sows. Serotyping of Y. enterocolitica revealed that only six (13.3%) of the examined isolates belonged to serotype O:3, with a considerable number of isolates (31.1%) having serotype O:5, while biochemical studies showed that as many as 40 of the 45 strains belonged to biotype 1A. As expected, the Y. enterocolitica strains of bioserotype 4/O:3 contained ail and ystA genes, while strains of biotype 1A contained only the ystB gene.  相似文献   
29.
In a breeding and fattening pig farm an increasing number of cases of abortion and generalized mycobacteriosis at slaughter occurred. Pathological findings compatible with mycobacteriosis, acid-fast organisms in tissues, and isolation of mycobacteria from tissue samples including fetuses, lungs and reproductive organs from sows, genital swabs, mesenteric lymph nodes, and from a sperm sample revealed the cause of the disease. Bacterial cultures were identified as Mycobacterium avium subsp. hominissuis using IS901-/IS1245-specific PCR. Genotyping of selected isolates from animals as well as from their environment by MIRU-VNTR analysis showed that the herd was infected with one single outbreak strain. The same genotype was also isolated from pigs of two other farms which showed comparable symptoms and were in direct contact with the index farm as well as from their environment. Immunological host responses detected by tuberculin skin test and ELISA gave positive results at herd level only. Despite the detection of other potential pathogens mycobacteria were regarded as the causative agent of the reproductive disorders. To our knowledge this is the first report of an epidemic mycobacterial infection in a pig holding associated with reproductive disorders, which could be attributed to one single virulent strain, and the first report of detection of M. avium subsp. hominissuis in pig sperm.  相似文献   
30.
According to studies, latent Toxoplasma gondii infection may affect several functions of the human brain. Here we search for the association between latent toxoplasmosis and cognitive performance. We tested 70 individuals for latent T. gondii infection. There were 26 Toxoplasma-infected subjects and 44 Toxoplasma-free subjects. Within these two groups we assessed cognitive performance using a set of standardized, widely recognized neuropsychological tests: Trail Making Test, Stroop Test, Verbal Fluency Test, Digit Span Test and N-back test. The relationship between chronic toxoplasmosis and cognitive performance was assessed, with adjustment for age and sex. Patients with latent toxoplasmosis performed worse on one neuropsychological test, N-back Test--percentage of correct answers (beta -8.08; 95% CI - 15.64 to -0.53; p < 0.05) compared to seronegative patients. However, after adjustment for age and sex, no statistically significant associations between latent toxoplasmosis and the scores on any cognitive tests were noticed. As statistically significant relationship was not observed, this study does not confirm that chronic latent T. gondii infection affects cognition.  相似文献   
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