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1.
Earthworm immune-competent cells (coelomocytes) can be adversely affected by soil metal contamination. The aim of the present paper was to perform comparative studies on the coelomocytes of four lumbricid species dermally exposed for 2 days to filter paper soaked with Ni, Cu, Zn, Cd, or Pb chlorides (1 mM). Coelomocytes were expelled by electro-stimulation, counted, and assayed ex vivo by flow cytometry and spectrofluorometry. The coelomocytes of Allolobophora chlorotica and Dendrobaena veneta contain both amoebocytes and riboflavin-storing eleocytes; consequently, they were subjected to assays based on flow cytometric quantification of autofluorescent eleocytes and spectrofluorometric measurement of riboflavin content in coelomocyte lysates. In Al. chlorotica, the number of coelomocytes, the percentage of eleocytes, and the amount of riboflavin were significantly lower in Cu-exposed worms although these cytometric parameters were less affected by Ni, Zn, Cd exposure, and entirely unaffected by Pb exposure. In D. veneta, such cellular effects were also only observed in Cu-exposed worms. The coelomic fluids of Aporrectodea caliginosa and Lumbricus rubellus are constitutionally impoverished of eleocytes; therefore, these species could not be subjected to assays measuring the riboflavin content of these granular cells. Rather, the amoebocytes of Ap. caliginosa and L. rubellus were subjected to flow cytometric measurements of in vitro neutral red uptake (NR). However, the NR uptake assay was technically demanding, requiring a strictly normalized incubation period over all samples to yield useful comparative data. In contrast, the riboflavin content in the coelomocyte lysates of eleocyte-rich species appears to be a robust and convenient immune-function biomarker of environmental stress.  相似文献   
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Because canine mammary tumours constitute a serious clinical problem and there are no good prognostic markers (only histopathological variables are used), the aim of the presented study was to find new malignancy markers as well as to identify intracellular pathways and biological processes characteristic for canine mammary malignancy. We compared gene expression of the most malignant mammary tumours (poorly differentiated cancers of the 3rd grade of malignancy) with less malignant tumours (well differentiated cancers of the 1st grade of malignancy). The results of our study indicated that in dogs the number of tumour-infiltrating myeloid cells or expression of myeloid-specific antigens by cancer cells is related to the cancer progression and may constitute a new marker of malignancy, however further studies in this field are required.  相似文献   
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Soil biodiversity includes organisms which spend a part or all of their life cycle on or in the soil. Among soil-dwelling animals, macro-fauna as an important group of animals have important effects on the dynamics of soil organic matter and litter decomposition process. The humus forms interact with the climatic conditions, flora, as well as soil fauna, and microbial activity. In new humus form classifications, soil organisms play an important role in separation of humus horizons from one another. The subject of this study was to determine the diversity of macro fauna for different humus forms. We determined humus forms using morphological classification, and then 69 random samples were taken from plots of 100 cm2 in area, and soil macro-fauna species were collected by hand sorting method. Two classes of humus forms, including Mull (with three humus orders, namely Dysmull, Oligomull, and Mesomull,) and Amphi (with four humus orders, namely Leptoamphi, Eumacroamphi, Eumesoamphi, and Pachyamphi) were identified. A number of 13 macro-fauna orders were identified using identification key. Among the humus orders, Shannon diversity, Simpson evenness and Margalef richness indices were the highest in Pachyamphi order. Arthropod diversity in Pachyamphi humus order was higher than those of Mull. These results showed that diversity of soil macrofauna increase by increasing the thickness of the organic horizons (OL, OF, OH), especially OH horizon.  相似文献   
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An epidemiological study to examine the sero-prevalence of zoonotic visceral leishmaniosis (ZVL) among domestic and wild canines in endemic foci of Iran was carried out during 1999-2003 to assess the distribution of the disease and the possible association between infection in dogs, wild canines and people. Anti-leishmanial antibodies were detected by the direct agglutination test (DAT). Parasitological study was performed for all captured wild canines and were detected in some of the seropositive dogs with specific clinical signs (n=107). Serum samples (n=1568) were collected from domestic dogs in villages that are known endemic foci of human visceral leishmaniosis (HVL). Wild canine sera were collected from jackals (Canis aureus, n=10), foxes (Vulpes vulpes, n=10) and wolves (Canis lupus, n=10). Of the 1568 serum sampled collected from domestic dogs, 222 (14.2%) were positive by DAT (1:320 and above). No statistically significant difference was found between male (15.2%) and female (11.8%) sero-prevalence (P=0.083). Dogs of 8 years and above showed the highest sero-prevalence (40.6%). Only 23.9% of the seropositive domestic dogs had clinical signs. Parasitology and serology tests that were performed in 30 wild canines showed 10% these animals were infected by Leishmania infantum. Ten out of 11 Leishmania spp. isolated from the dogs and wild canines were identified as L. infantum and one other as L. tropica by molecular and biochemical techniques. For the first time in Iran, L. infantum and L. tropica were isolated from viscera of both a wolf and a domestic dog.  相似文献   
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The purpose of this review is to summarize the effectiveness, modes of action and commercial application of herbal plants and their derivatives as growth promoters for animal. Feed supplements are a group of feed ingredients that can cause a desired animal response in a non-nutrient role such as pH shift, growth, or metabolic modifier (Hutjens, 1991). Common feed additives used in animal diets include immunostimulators, antimicrobials, antioxidants, pH control agents and enzymes. Herbal plants, are a new class of growth promoters and in recent years this feed additives have gained extensive attention in the feed industry. They are a wide variety of herbs, spices, and products derived thereof, and are mainly essential oils. Although numerous reports have demonstrated antioxidative and antimicrobial and immune stimulation efficacy in vitro, respective experimental in vivo evidence is still quite limited. A limited number of experimental comparisons of herbal plants feed additives with antibiotics or organic acid have suggested similar effects on the animal gut microflora. Gut microflora has significant effects on host nutrition, health, and growth performance by interacting with nutrient utilization and the development of gut system of the host. In addition, some phytogenic compounds seem to promote intestinal mucus production. However, the future of using herbs in animal feeding will in great measure depend on the knowledge of chemical structure, their value and characteristics of practical herbs or their extract physiological needs and well-being of animal, and, above all on consumer’s preferences and expectations.  相似文献   
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Irrigation and nitrogen management are two of the most important factors affecting production efficiency and environmental quality in potato cropping systems. Field studies were conducted in 1990 and 1991 to determine the interactive effects of irrigation amount and N timing on potato yield, quality and nitrate leaching potential. Sprinkler irrigation was applied at approximately 1.0, 1.2 or 1.4 times estimated evapotranspiration (ET) to Russet Burbank potatoes grown on a silt loam soil. Following tuber initiation, a total of 132 kg N/ha was applied through the irrigation system to N treatment subplots using either six weekly 22 kg N/ha applications or 3 biweekly 44 kg N/ha applications. Excessive irrigation reduced root zone and petiole NO3-N concentrations during substantial portions of the tuber bulking period. Biweekly 44 kg N/ha applications in 1991 produced higher and more consistent earlyseason root zone NO3-N concentrations in the 1.2 and 1.4 ET plots than did the weekly 22 kg N/ha applications. Late-season tuber dry weight, total plant dry weight and plant N uptake were not affected by irrigation rate or N timing. However, excessive irrigation reduced U.S. No. 1 yield and yield of tubers >284 g in both 1990 and 1991 and reduced total yield in 1990. Biweekly N applications produced higher U.S. No. 1 yields than weekly N applications at all irrigation levels. Excessive irrigation also reduced NO3-N remaining in the top 60 cm of soil at the end of the growing season. These results show that irrigating at optimal rates and applying split N at two week intervals on a silt loam soil can maximize Russet Burbank yield and quality while minimizing NO3-N losses.  相似文献   
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Background: Initial studies have shown that low-energy ultrasound stimulates living tissue cells to reduce regeneration or speed up their recovery. The purpose of this study was to examine the effects of various ultrasound parameters on the speed of recovery in injured sciatic nerves NMRI.Methods: NMRI mice (n = 200) with injured left paw, caused by crushing their sciatic nerves, were randomly selected. The animals were exposed to ultrasound radiation with various frequencies, intensities, and exposure time. They were allocated into 20 groups (19 treatment and 1 control groups). Sciatic functional index (SFI) test was used to evaluate the difference between the groups with respect to functional efficiency of the sciatic nerve and its recovery. SFI ، (P=0.000).Results: The results of SFI test obtained from the 14th day showed a significant difference among the groups (P<0.05). On the 14th day after treatment, one of the groups (US11) recovered up to 90%..Conclusion: Altered ultrasound exposure parameters had more favorable outcomes compared with our previous work.Key Words: Sciatic nerve, Ultrasonic therapy, Regeneration  相似文献   
10.
BACKGROUND: Progressive cognitive decline is one of the hallmark symptoms of Alzheimer's disease (AD) which can be modeled by beta-amyloid injection into specific regions of brain. Since epigallocatechin-3-gallate (EGCG) is a potent antioxidant agent which its role against oxidative stress and inflammation has been shown in prior studies, we tried to determine whether EGCG administration protects against beta-amyloid-induced memory and coordination impairment in rats. METHODS: Animals (male Wistar rats) were divided into four groups: sham operated, EGCG-pretreated sham operated (sham+EGCG), untreated lesion (lesion), and EGCG-pretreated lesion (lesion+EGCG). Animals in lesion, lesion+EGCG, and sham+EGCG groups received sterile saline or saline plus EGCG (10 mg/kg) intraperitoneally one day pre-surgery and every other day for three weeks. The lesion was induced one day after EGCG pretreatment by injection of 4 microl of sterile saline or water containing 2 nmol/microl beta-amyloid (1-40) into the hippocampal fissure. For behavioral analysis, psychomotor coordination (PMC) index and spontaneous alternation behavior were assessed using Rota-rod Treadmill and Y-maze, respectively at the third week post-lesion. RESULTS: We found that beta-amyloid (1-40) injection into hippocampus can decrease these behavioral indexes in lesion group in comparison with sham group which is similar to behavioral changes in AD. On the other hand, pretreatment with EGCG can improve the PMC index and spatial Y-maze alternation in the lesion+EGCG group in comparison with lesion group. CONCLUSION: We concluded that EGCG can be effective in restoring beta-amyloid-induced behavioral derangements in rats regarding coordination and memory abilities.  相似文献   
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