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1.
The extreme use of ethanol causes metabolic and pathologic changes in testes and urogenital system in different animal species. The enzyme alcohol dehydrogenase (ADH) catalyses the conversion of ethanol into carcinogenic metabolite acetaldehyde which is partly excreted into the urine. However, papers relating the chronic ethanol consumption to the urethral morphology are unknown. This work evaluates the toxic effect of the chronic ethanol ingestion on the urethral epithelium of UChA and UChB rats. Conventional techniques of histology, histochemistry, immunohistochemistry and ultrastructural analysis were used. The analysis showed the presence of lipid drops and intercellular spaces in the epithelial cells in the urethra of UChA and UChB rats compared to control rats. Urethral neuroendocrine cell were observed and characterized for presenting vesicles containing electron-dense granules associated with nervous fibers. We conclude that the chronic consumption of ethanol induces the presence lipid drops in the epithelial cells of the urethra of UChA and UChB rats. The NE cells of the urethra of UChA and UChB rats did not show alterations under chronic effect of the ethanol.  相似文献   
2.

Background  

Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH.  相似文献   
3.
The influence of daily energy doses of 0.03, 0.3 and 0.9 J of He-Ne laser irradiation on the repair of surgically produced tibia damage was investigated in Wistar rats. Laser treatment was initiated 24 h after the trauma and continued daily for 7 or 14 days in two groups of nine rats (n=3 per laser dose and period). Two control groups (n=9 each) with injured tibiae were used. The course of healing was monitored using morphometrical analysis of the trabecular area. The organization of collagen fibers in the bone matrix and the histology of the tissue were evaluated using Picrosirius-polarization method and Masson's trichrome. After 7 days, there was a significant increase in the area of neoformed trabeculae in tibiae irradiated with 0.3 and 0.9 J compared to the controls. At a daily dose of 0.9 J (15 min of irradiation per day) the 7-day group showed a significant increase in trabecular bone growth compared to the 14-day group. However, the laser irradiation at the daily dose of 0.3 J produced no significant decrease in the trabecular area of the 14-day group compared to the 7-day group, but there was significant increase in the trabecular area of the 15-day controls compared to the 8-day controls. Irradiation increased the number of hypertrophic osteoclasts compared to non-irradiated injured tibiae (controls) on days 8 and 15. The Picrosirius-polarization method revealed bands of parallel collagen fibers (parallel-fibered bone) at the repair site of 14-day-irradiated tibiae, regardless of the dose. This organization improved when compared to 7-day-irradiated tibiae and control tibiae. These results show that low-level laser therapy stimulated the growth of the trabecular area and the concomitant invasion of osteoclasts during the first week, and hastened the organization of matrix collagen (parallel alignment of the fibers) in a second phase not seen in control, non-irradiated tibiae at the same period. The active osteoclasts that invaded the regenerating site were probably responsible for the decrease in trabecular area by the fourteenth day of irradiation.  相似文献   
4.
In addition to dermatological complications, acne can affect the quality of life of individuals in numerous ways, such as employment, social habits and body dissatisfaction. According to our expertise, caprylic acid and propanediol would not have a direct action on Cutibacterium acnes. Despite this, we investigated the existence of a synergistic effect among xylitol, caprylic acid and propanediol as a mixture of compounds representing a single topical active ingredient that could benefit the treatment against acne. In vitro and in vivo assays were performed to challenge and to prove the efficacy of propanediol, xylitol and caprylic acid (PXCA) against acne. PXCA had its MIC challenged against C. acnes (formerly Propionibacterium acnes) and Staphylococcus aureus, resulting in concentrations of 0.125% and 0.25%, respectively, and it also developed antimicrobial activity against C. acnes (time-kill test). PXCA was able to reduce the 5-alpha reductase expression in 24% (p < 0.01) in comparison with the testosterone group. By the end of 28 days of treatment, the compound reduced the skin oiliness, porphyrin amount and the quantity of inflammatory lesions in participants. According to the dermatologist evaluation, PXCA improved the skin’s general appearance, acne presence and size.  相似文献   
5.
Fusion cross-sections for the 7Li + 12C reaction have been measured at energies above the Coulomb barrier by the direct detection of evaporation residues. The heavy evaporation residues with energies below 3 MeV could not be separated out from the α-particles in the spectrum and hence their contribution was estimated using statistical model calculations. The present work indicates that suppression of fusion cross-sections due to the breakup of 7Li may not be significant for 7Li + 12C reaction at energies around the barrier.  相似文献   
6.
It has recently been shown that lustre decoration of medieval and Renaissance pottery consists of silver and copper nanoparticles dispersed in the glassy matrix of the ceramic glaze. Here the findings of an X-ray absorption fine structure (XAFS) study on lustred glazes of shards belonging to 10th and 13rd century pottery from the National Museum of Iran are reported. Absorption spectra in the visible range have been also measured in order to investigate the relations between colour and glaze composition. Gold colour is mainly due to Ag nanoparticles, though Ag+, Cu+ and Cu2+ ions can be also dispersed within the glassy matrix, with different ratios. Red colour is mainly due to Cu nanoparticles, although some Ag nanoparticles, Ag+ and Cu+ ions can be present. The achievement of metallic Cu and the absence of Cu2+ indicate a higher reduction of copper in red lustre. These findings are in substantial agreement with previous results on Italian Renaissance pottery. In spite of the large heterogeneity of cases, the presence of copper and silver ions in the glaze confirms that lustre formation is mediated by a copper- and silver-alkali ion exchange, followed by nucleation and growth of metal nanoparticles.  相似文献   
7.
8.
This paper proposes a numerical method for the solution of equilibrium problems of solids which do not support tension. Some boundary-value problems are solved numerically and the solution obtained is compared to the exact one.
Sommario In questo lavoro viene proposto un metodo numerico per la soluzione di problemi di equilibrio di solidi non resistenti a trazione. Vengono successivamente risolti numericamente alcuni problemi di equilibrio e la soluzione ottenuta è confrontata con quella esatta.
  相似文献   
9.
Padovani  Cristina 《Meccanica》2002,37(6):515-525
The strong ellipticity of the elasticity tensor of a linearly hyperelastic, transversely isotropic material is investigated. The necessary and sufficient conditions for the elasticity tensor to be strongly elliptic are determined for the five constants characterizing it.  相似文献   
10.
Copper diffusion in ion-exchanged soda-lime glass   总被引:3,自引:0,他引:3  
Cu-alkali ion exchange in silicate glasses gives rise to a peculiar copper distribution, with the presence of both the Cu2+ and Cu+ oxidation states. Grazing incidence X-ray absorption near-edge structure spectroscopy and secondary ion mass spectrometry were performed on different ion-exchanged samples. The results show that the Cu2+/Cu+ ratio is strongly depth-dependent. The relative presence of the two species throughout the exchanged region turns out to be governed by their different diffusion regimes, while the chemistry of the red-ox process is shown to play a minor role. A phenomenological model is proposed to describe the diffusion process. PACS 61.10.Ht; 61.43.Fs; 82.65.+r; 67.80.Mg  相似文献   
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