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11.
It is common knowledge that fish are a nutritious component of a human diet, as they constitute a valuable and desired source of protein and polyunsaturated fatty acids. However, they are likely to pose a risk to consumer health. The presence of pathogenic bacteria or their toxins, parasites, biogenic amines and toxins or chemical residues may be a causal agent of foodborne illnesses in humans, sometimes even with fatal effect. Usually, infections are a result of insufficient thermal treatment or consumption of raw fish dishes. There are also risk factors that cannot be eliminated by such treatments as cooking, salting or freezing.  相似文献   
12.
Mast cells (MCs) are well known for their neoplastic transformation in solitary and multiple cutaneous mast cell tumours (MCTs), as well as visceral and systemic mastocytosis. Dogs have a unique risk of developing cutaneous MCTs, and they account for 7% to 21% of all canine skin tumours. The aetiology of canine MCTs is unknown but is probably multifactorial. This article reviews up-to-date knowledge on the pathogenesis, the clinical presentation, the clinical prognostic factors, the diagnostic workup including clinical staging, cytological findings, histological findings and the various grading systems which have been evaluated based on morphology, the assessment of proliferation markers and other factors such as vessel density. Furthermore, detailed information about current treatment protocols for canine cutaneous MCTs is provided.  相似文献   
13.
Both resiniferatoxin (RTX) and tetrodotoxin (TTX) have been reported to be effective in several clinical trials aiming to cure urinary bladder dysfunction. The goal of this experiment was to study the effect of intravesical administration of RTX and TTX on the chemical coding of paracervical ganglion (PCG) neurons that supply the urinary bladder in pigs. The vasoactive intestinal peptide (VIP) and the opioid family member Leu5-enkephalin (LENK) are both known for their regulatory effects in the function of the porcine genitourinary tract. The PCG neurons innervating the urinary bladder were identified by application of the retrograde tracer Fast Blue (FB), injected into the bladder wall prior to intravesical RTX or TTX administration. Immunocytochemical detection of LENK and VIP expression in the FB-labelled perikarya revealed that in the control group 25.15% of the FB-positive PCG neurons contained LENK, and 9.22% of them expressed VIP. Intravesical infusion of RTX resulted in an increase in the number of LENKIR neurons to 48.19% and VIP-IR perikarya to 11.25%. Optional treatment with TTX induced increase of LENK-IR neurons up to 81.67% and VIP-IR population to 16.46% of the FB-positive PCG cells. The present results show that both neurotoxins affect the chemical coding of PCG nervous cells supplying the porcine urinary bladder and that they stimulate both LENK and VIP expression. Furthermore, the results indicate a possible involvement of LENK and VIP neurons in the mechanisms of action of RTX and TTX in the therapy of overactive bladder disorder.  相似文献   
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The aim of the study was to evaluate the influence of low dose (LOEL - lowest observed effect level) of zearalenone (200 microg/kg b.w.), applied per os for 7 days (short-term intoxication), on sexual behavior, concentration of the examined xenobiotic and its metabolite and selected estrogens in sexually immature gilts: ovariohysterectomised (group D1) and intact (group D2) animals. Clinical signs of oestrus (reddening, oedema and hyperaemia of the vulva and serorhoea from the reproductive tract--lack of standing reflex) were obserwed in group D1 on day 6 and in group D2 on day 4 of the experiment. Laboratory analyses of blood plasma were carried out determine the presence of zearalenone and alpha-zearalenole. They revealed an increase in the level of alpha-zearalenol before the oestrus, decrease in total amount of both examined substances on day when the oestrus appeared and increase in the level of both examined xenobiotics in the post oestrus period together with the higher share of zearalenone. Medium concentrations of estrone and estradiol within the borders of method determination in the majority of periods examined. Higher levels of estrone (32.0 pg/ml) were found on day 4, in the group D2 and estradiol (6.5 pg/ml) on day 6 in the D2 group. The presents study revealed that zearalenone applied per os at LOEL dose causes the incidence of apparent sexual readiness (without standing reflex) in sexually immature gilts with the somatically immature reproductive system.  相似文献   
16.
SUMMARY: Two different reciprocal translocations, rcp (8;14) (p21;q25) and rcp (7;13) (q13;q46), were described for the first time in Poland in the Polish Landrace and Duroc pigs. Observation of synaptonemal complexes showed the presence of a quadrivalent composed of translocational chromosomes and their homologues. Individuals carrying translocations were characterized by normal external appearance and correct semen parameters. Analysis of fertility made on the basis of litter size demonstrated that fertility decreased by 25% in the carrier of translocation rcp (8;14) and by 52% in the carrier of translocation rcp (7;13). ZUSAMMENFASSUNG: Zum erste mal festgestelte gegenseitige Translokationen bei Schweine in Polen Bein Polnischen Landras und Duroc Schweinen wurden zum erstenmal in Polen, zwei verschiedene reciproke Translokationen-rcp (8;14) (p21;q25) und rcp (7;13) (q13;q46)-festgestellt. Anhand der Beobachtungen des Synaptonemal Complex wurde die Anwesenheit eines Tetravalent nachgewiesen, welches aus Translokationschromosomen und seinen Homologen zusammengesetzt ist. Die Translokationstiere hatten normale Exterieur und Spermaparameter. Aufgrund der Fortpflanzungsergebmissen wurden verminderte Fruchtbarkeit bei Translokationstieren rcp (8;14)-um 25% und bei Translokationstieren rcp (7;13)-um 52% festgestellt. RéSUMé: Les translocations réciproques identifiées pour la prèmière fois chez les porcs levés en Pologne Chez les porcs des races Landrace et Duroc on a constaté, pour la première fois en Pologne deux translocations réciproques différentes-rcp (8;14) (p21;q25) ainsi que rcp (7;13) (q13;q46). L'observation des complexes synaptonémals a manifesté la présence du quadrivalent composé de chromosomes de translocation et de leurs homologes. Les animaux-les porteurs de la translocation ont se caractérisé par l'extérieur normal et par les paramètres réguliers du sperme. L'analyse de la fertilité expérimenté selon de la taille des portées a démontré la réduction de la fertilité pour le porteur de la translocation rcp (8;14) à 25% cependant pour les porteurs de la translocation rcp (7;13) à 52%.  相似文献   
17.
The aim of the monitoring of zearalenone presence in the blood plasma of women with neoplastic lesions in the reproductive tract was to asses whether the phytosteride is noted in the patients blood and whether the correlation exists between its presence and the incidence of particular neoplasm. The presence of zearalenone or its metabolite--alpha-zearalenole, was noted in 13.51% of the examined women. In 60% of the patients with the confirmed presence of the xenobiotic it was noted in the lowest concentrations. These patients had neoplastic lesions of Carcinoma corpus uteri type.  相似文献   
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19.

Background

The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se.

Methods

Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na2SeO3/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy.

Results

The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons.

Conclusions

Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.  相似文献   
20.
The IgE specific Fc-? receptor test is widely used for serological evaluation of allergic canine patients. Aim of the study was to evaluate intra- and interlaboratory variability in three independent laboratories. Duplicate serum aliquots from 15 atopic dogs were submitted simultaneously to 3 laboratories (LA, LB, LC), which subsequently performed the test in a blinded fashion. LA and LC analysed sera for 35 allergens and expressed the results as optical density units (OD), while LB analysed 15 allergens and provided reaction grades (RG). Results were compared with three factorial ANOVA. Intralaboratory variability was evaluated by calculating the dispersion factor for data of LA and LC and standard deviation (SD) for LB. Correlation coefficients (r) were used to evaluate interlaboratory variability. Depending on the allergens, intralaboratory dispersion factor for LA and LC varied from 1.15 to 6.63 and 1.19 to 6.17, respectively. In LB the SD varied between 0 and 0.6 RG. Regarding interlaboratory variability, correlation of OD values between LA and LC was excellent (r > 0.8, p < 0.001) for 13 of 35 allergens. There was a significant difference in OD results for 9 allergens. The results were significantly correlated (r > 0.8, p < 0.001) for all except 3 allergens (Dermatophagoides pteronyssinus, mixed grasses, nettle). As far as negative/positive results were concerned, intralaboratory differences were 3.14% and interlaboratory differences were 4.76%.  相似文献   
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