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21.
The aim of this work was to determinate the effect of carbamate insecticide bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-yl N-methylcarbamate) on selected parameters of rabbit homeostasis. Animals were divided into four groups (control C, and experimental groups E1, E2 and E3 according to days of administration 10, 15 and 25 days). Animals from experimental groups received bendiocarb per os in a dose 5 mg/kg of body weight per day. Significant increase of creatinine content in E3 group (the longest administration of bendiocarb), increase of aspartate aminotransferase (E1 and E3 against control group) and gamma glutamyl transferase (E3 against control group) and decrease of glutamate dehydrogenase (E1 against control group) inform about possible failure of liver and/or kidney caused by bendiocarb. Decrease of haemoglobin (significantly in E3 group against control group), mean corpuscular haemoglobin (MCH) concentration (in all experimental groups), platelet count (in all experimental groups) can signify defection in haemoplastic system.  相似文献   
22.
Keloids are skin fibroproliferative disorders, resulting from abnormal healing of deep cutaneous injuries. Cryosurgery, the most common treatment for keloids, causes skin traumas. Even though the clinical practice of cryosurgery has increased, effective wound healing therapy is still lacking. In this investigation, nonwoven nanofibrous patches composed of ulvan, a marine sulfated polysaccharide exhibiting anti-inflammatory and antioxidant activities, and polyethylene oxide (PEO) were fabricated through electrospinning and characterized. Their wound healing efficacy on skin traumas resulting from cryosurgical treatment of keloids was clinically tested and evaluated in comparison to a reference product. Twenty-four volunteer patients undergoing cryosurgery as a treatment of keloids were selected to apply either the ulvan/PEO patch or the reference product for 21 days. The ulvan/PEO patch, 21 days after cryosurgery, showed significant wound healing, elimination of skin inflammation, restoration of biophysical parameters similar to normal values and significant decrease in haemoglobin concentration, skin texture and volume, while no discomfort or adverse reaction was observed. In contrast, the reference product showed inferior performance in all evaluated parameters. The designed ulvan/PEO patch represents the first wound dressing to effectively heal skin trauma after cryosurgical treatment of keloids.  相似文献   
23.
The effects of NaCl supplementation (0.0%, 2.5%, 5.0%, 7.5% and 10.0% dry weight of a basal diet) on growth, gill histological alterations and osmoregulation of juvenile cobia reared in low‐salinity water (5 g L?1) were assessed. At the end of the experiment, gills were sampled for Na+, K+‐ATPase activity determination and histological evaluation. In all treatments, no mortality was observed. Results showed that dietary NaCl supplementation did not alter growth. At the highest supplementations (7.5% and 10.0%), juvenile cobia showed higher feed intake and feed conversion ratio. Na+, K+‐ATPase activity was higher in fish fed the diet without salt supplementation than in those fed with NaCl‐supplemented diets. The number of chloride cells significantly increased with increasing dietary salt level, being 2.5‐fold higher in fish fed with 10.0% NaCl supplementation (41 cells mm?2) than in those from the non‐supplemented fed group (16 cells mm?2). These findings indicate that dietary salt supplementation stimulated chloride cell proliferation paralleled with a reduction in the gill Na+, K+‐ATPase activity, suggesting a possible decrease in energy consumption associated with osmoregulation. However, the suggested energy sparing did not have a significant impact on juvenile cobia growth.  相似文献   
24.
Over a 1-year period, we carried out an analysis for the presence of Giardia and Cryptosporidium (oo)cysts in 934 specimens taken from four species of shellfish farmed in the Varano Lagoon. We also studied the chemical, physical and meteo-climatic parameters in the same environment, to evaluate the possible effects of environmental conditions on protozoan contamination in farmed shellfish. Using both IF and molecular tests, all 38 pools of shellfish gave negative values for Giardia and Cryptosporidium oo/cysts, thus confirming previous investigations. The environmental factors considered having a negative influence on the survival of Giardia and Cryptosporidium are high water temperatures (8–29°C) and high salinity levels (23–32?ppt). However, the small amount of freshwater discharged into the lagoon (up to 0.0091?m3 s?1), the long-lasting solar irradiation (mean of 896?W?m?2) and the shallowness of the lagoon (mean 2.5?m) may also have a synergic effect in limiting the presence of Giardia and Cryptosporidium in the lagoon.  相似文献   
25.
The medial temporal lobe is crucial for the ability to learn and retain new declarative memories. This form of memory includes the ability to quickly establish novel associations between unrelated items. To better understand the patterns of neural activity during associative memory formation, we recorded the activity of hippocampal neurons of macaque monkeys as they learned new associations. Hippocampal neurons signaled learning by changing their stimulus-selective response properties. This change in the pattern of selective neural activity occurred before, at the same time as, or after learning, which suggests that these neurons are involved in the initial formation of new associative memories.  相似文献   
26.
This study examined the subsets of T lymphocytes in the thymus, spleen and mesenteric lymph nodes as well as the subsets of B lymphocytes in the spleen and mesenteric lymph nodes in mice administered chitosan adipate (20 mg/kg) intraperitoneally once or four times at 24 h intervals. The results showed that chitosan adipate decreased the percentage of immature CD4+CD8+ thymic T cells and increased the percentage of mature CD4+ and CD8+ thymocytes. The most significant stimulating effect was observed after four injections. A single exposure to chitosan adipate increased the percentage of CD4+ mesenteric lymph node cells, but four injections of the drug increased the percentage of CD4+ and CD8+ mesenteric lymph node cells. Chitosan adipate had no effect on the subset of splenic T cells. In contrast, chitosan adipate administered either once or four times increased the percentage of CD19+ splenocytes but had no effect on the percentage of CD19+ mesenteric lymph node cells. Overall, chitosan adipate induces the maturation and differentiation of thymocytes, and regulates the number of B splenic cells and lymph node T cells irrespective of the number of doses.  相似文献   
27.
The equine head is an anatomically complex area, therefore advanced tomographic imaging techniques, such as computed tomography or magnetic resonance imaging (MRI), are often required for diagnosis and treatment planning. The purpose of this multicenter retrospective study was to describe MRI characteristics for a large sample of horses with head disorders. Horses imaged over a period of 13 years were recruited. Eighty‐four horses met the inclusion criteria, having neurological (n = 65), sinonasal (n = 14), and soft tissue (n = 5) disorders. Magnetic resonance imaging accurately depicted the anatomy and allowed identification of the primary lesion and associated changes. There were good correlations between MRI findings and intraoperative or postmortem results. Magnetic resonance imaging showed the exact localization of the lesions, their size, and relation to surrounding structures. However, in the neurological group, there were 45 horses with no MRI abnormalities, 29 of which had a history of recurrent seizures, related to cryptogenic epilepsy. Magnetic resonance imaging was otherwise a valuable diagnostic tool, and can be used for studying a broad range of head disorders using either low‐field or high‐field magnets.  相似文献   
28.
In humans, the cytochrome P450 3A (CYP3A) subfamily is involved in midazolam (MDZ) biotransformation into 1′- and 4-hydroxy metabolites, and the former serves as a probe for CYP3A catalytic activity. In veterinary species is still crucial to identify enzyme- and species-specific CYP substrates; thus, the aim of this study was to characterize MDZ oxidation in cattle liver. A HPLC-UV method was used to measure 1′- and 4-hydroxy MDZ (1′- and 4-OHMDZ, respectively) formation in cattle liver microsomes and assess the role of CYP3A by an immunoinhibition study. Moreover, MDZ hydroxylation was evaluated in 300 cattle liver samples and results were correlated with testosterone hydroxylation. Formation of both metabolites conformed to a single-enzyme Michaelis–Menten kinetics. Values of Vmax and Km were 0.67 nmol/min/mg protein and 6.16 μM for 4-OHMDZ, and 0.06 nmol/min/mg protein and 10.08 μM for 1′-OHMDZ. An anti-rat CYP3A1 polyclonal antibody inhibited up to 50% and 94% 1′- and 4-OHMDZ formation, respectively. MDZ oxidation in liver microsomes was poorly correlated with testosterone hydroxylation. In conclusion, cattle metabolized MDZ to 1′-OHMDZ and 4-OHMDZ. The immunoinhibition results indicated a major contribution of CYP3As to 4-OHMDZ formation and the involvement of other CYPs in 1′-OHMDZ production, paving the way for further investigations.  相似文献   
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30.
Longer life expectancy has led to an increase in efforts directed to the discovery of new healing agents for disorders related to aging, such as bone diseases. Harboring an incredible variety of bioactive metabolites, marine organisms are standing out as fruitful sources also in this therapeutic field. On the other hand, the in vivo zebrafish model has proven to be an excellent low-cost screening platform for the fast identification of molecules able to regulate bone development. By using zebrafish larvae as a mineralization model, we have thus evaluated the effects of the crude acetonic extract from the marine sponge Aplysina aerophoba and its bromotyrosine components on bone development. Obtained results led to the selection of aerophobin-1 (1) as a promising candidate for applications in regenerative medicine, paving the way for the development of a novel therapeutic option in osteoporosis treatment.  相似文献   
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