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41.
The addition of fiveFusarium species, cultured on wheat grain, to the standart chicken diet DKA starter, caused atrophic changes in the thymus and testes, as observed in the microscopic picture of these organs. The degree of lesions were depended on theFusarium species and its amount added to the standart diet.  相似文献   
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Atrial fibrillation increases the risk of thrombus formation. It is commonly responsible for cerebral stroke whereas less frequently for pulmonary embolism. The aim of the study was to describe the morphology of the left atrial appendage in the human heart with respect to sex, age and weight. Macroscopic examination was carried out on 100 left appendages taken from the hearts of the patients aged 18–77, both sexes. All hearts preserved in 4% water solution of formaldehyde carried neither marks of coronary artery disease nor congenital abnormalities. Three axes of appendage orientation were performed. After the appendage had been cut off, morphological examination was performed in long and perpendicular axes. Measurements of the appendages were taken from anatomical specimens and their silicone casts. We classified the left atrial appendage into 4 morphological groups according to the number of lobes. Most left atrial appendages in female population were composed of 2 lobes. In the male group typically 2 or 3-lobed appendages were observed. The mean left atrial appendage orifice ranged from 12.0 to 16.0 mm and the most significant difference in the orifices between males and females was observed in LAA type 2 (about 3.3 mm). A smaller orifice and narrower, tubular shape of the LAA lobes could explain a higher risk of thrombus formation during nonvalvular atrial fibrillation in women. Knowledge of anatomical variability of the LAA helps diagnose some undefined echoes in the appendage during transesophageal echocardiographic examination.  相似文献   
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Mitochondrial function plays an important role in multiple human diseases and mutations in the mitochondrial genome have been detected in nearly every type of cancer investigated to date. However, the mechanism underlying the interrelation is unknown. We used human cell lines depleted of mitochondrial DNA as models and analyzed the outcome of mitochondrial dysfunction on major cellular repair activities. We show that the deoxyribonucleoside triphosphate (dNTP) pools are affected, most prominently we detect a 3-fold reduction of the dTTP pool when normalized to the number of cells in S-phase. It is known that imbalanced dNTP pools are mutagenic and in accordance, we show that mitochondrial dysfunction results in chromosomal instability, which can explain its role in tumor development. We did not find any straightforward correlation between ATP levels and dNTP pools in cells with defective mitochondrial activity. Our results suggest that mitochondria are central players in maintaining genomic stability and in controlling essential nuclear processes such as upholding a balanced supply of nucleotides.  相似文献   
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In this study there was demonstrated the process of appearance and intensity of colonisation of the swine's skin samples by exposing them on agar plate cultures or immersed in liquid cultures of B. anthracis. The results of research were documented with photos of coloured histological preparations. As a result of the research there was demonstrated the possibility of infection and colonisation of skin consignment by B. anthracis from accidental located skin of died or killed animals because of anthrax. This colonisation may occur in the period 3 to 24 hours in optimal conditions. Anthrax bacteria are starting to penetrate and colonize the skin samples during 3 hours with exposing them from the hypodermic side; whereas penetration and colonisation from epidermis side appears after 24 hours. The results demonstrated that in natural conditions for optimal cultivation of B. anthracis there can be a possibility of infection and colonization of health parts of the skin's in storage skin for the longer period of time or longer transport.  相似文献   
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Hair loss may accompany several endocrine disorders, including hypopituitarism, hypothyreosis, hyperthyreosis, hypoparathyroidism, diabetes mellitus, growth hormone deficiency, hyperprolactinaemia, polycystic ovary syndrome, SAHA syndrome, congenital adrenal hyperplasia, Cushing syndrome, or virilising tumours. Most patients with endocrine disorders present with diffuse non-scarring alopecia, such as anagen effluvium, telogen effluvium or androgenetic alopecia. Focal non-scarring alopecia, such as alopecia areata coexisting with autoimmune thyroiditis, is less frequent and scarring alopecia is a rare finding in patients with endocrine abnormalities. In some cases an endocrine disorder may be suspected based on dermatological findings during hair loss evaluation. Classic methods of hair evaluation include hair weighing, pull test, wash test, the trichogram, and histopathological examination. Newly developed non-invasive diagnostic techniques include the phototrichogram, trichoscan, trichoscopy, and reflectance confocal microscopy.  相似文献   
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