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61.
Toll-like receptors (TLRs) and β-defensins are important components of the innate immune system. This study aimed to evaluate endometrial mRNA levels of TLRs (1/6, 2, 4, and 5) and β-defensin 5 in Holstein cows by quantitative real time RT-PCR. Uterine biopsies were performed from 6 to 12 h after parturition, and cows were divided into two groups: (i) cows with placental retention and clinical signs of uterine infection until 45 days postpartum (n=10) or (ii) cows with normal puerperium (n=10). All cows had detectable levels of TLRs and β-defensin 5 mRNAs, but these levels did not differ between groups (P>0.05). Levels of TLR4 mRNA had a positive and significant correlation with the time required for uterine involution in both groups.  相似文献   
62.
The use of a concentrate emulsion of Melia azedarach green fruits and a suspension of the fungus Beauveria bassiana was evaluated in the control of Rhipicephalus microplus on artificially infested cattle. The evaluation was conducted following the protocol established by the Brazilian Agriculture Ministry. Five groups of 4 or 5 animals were allocated to one of the following treatments: emulsion concentrate of M. azedarach at 0.25% (T AZED 0.25%), emulsion concentrate of M. azedarach at 0.5% (T AZED 0.5%), B. bassiana at 2.4 × 10(8) conidia (T BASS), association of the concentrate of M. azedarach at 0.25% with B. bassiana at 2.4 × 10(8) conidia (T AZED 0.25%+BASS), and control (untreated). The association of the two compounds provided better results than any one isolated treatment, indicating compatibility or perhaps a synergy between M. azedarach and B. bassiana. This treatment resulted in fewer engorged females (129 ± 70) than in the control group (233 ± 82), showing high performance against all developmental stages of the tick. Results revealed an apparent synergistic effect of M. azedarach and B. bassiana in the control of R. microplus that should be further investigated.  相似文献   
63.
Tumour necrosis factor (TNF), a pleiotropic cytokine that regulates cell growth and differentiation as well as the synthesis of other cytokines, has been identified in the uterus of several species describing a cyclic pattern, eventually under ovarian steroid regulation. Information is yet limited on the presence of TNF protein in the canine endometrium during the oestrous cycle and early pregnancy. This study depicts the temporal immunolocalization of TNF in the bitch endometrium along the oestrous cycle and changes associated with the early steps of embryo invasion. TNF immunolabelling was found in both the stromal fibroblasts and epithelial components of the canine endometrium in all stages studied. Stromal immunostaining was more intense than that of the epithelia, in all the stages of the oestrous cycle. In addition, a tendency for a decrease in the surface epithelium intensity score was found in early dioestrus. A positive glandular content was only observed in anoestrus and proestrus stages. In early pregnancy (days 13-16), TNF immunolabelling was detected at the embryo-maternal surface, in the syncytium cords and the trophoblast, as well in the endometrial stroma and the basal endometrial glands, but not in the lacunar epithelium. The overall TNF immunoreactivity was higher in early pregnancy samples in comparison with those of the early dioestrus and dioestrus stages, suggesting it plays a role during implantation.  相似文献   
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65.
Cholangiohepatopathy was induced in 5 lambs by oral administration of extracts from signal grass (Brachiaria decumbens) in Brazil. Grossly there were pale foci multifocally distributed throughout the hepatic parenchyma in 4 lambs. The microscopic changes, which were similar to those produced by other steroidal sapogenins-containing plants such as Tribulus terrestris and Panicum spp., included multifocal cholangitis, bile duct proliferation, and the presence of crystals in the biliary system.  相似文献   
66.
This report presents the case of a nine-month-old bitch with incomplete occlusion of the skin and mucosa between the anus and dorsal commissure of the vulva. This anomaly, known as anovulvar cleft, was associated with a vaginal prolapse-hyperplasia. Anovulvar cleft is a rare condition in bitches and is caused by incomplete closure of the dorsal urogenital folds. Anovulvar cleft can lead to clitoritis, abrasion, dryness and devitalisation of the smooth exposed mucosa. Surgery can correct the condition. In the present study, surgical resection of the hyperplasic vaginal tissue associated with perineoplasty using an inverted V-shaped incision showed excellent results. An ovariohysterectomy was also performed to prevent recurrence of the vaginal prolapse-hyperplasia.  相似文献   
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68.
The loads imposed by modern farm machinery have considerable potential to increase subsoil stress. Within the context of economically viable and environmentally sustainable systems, the practices associated with subsoil damage and methods for avoidance are identified. The greatest potential for damage is on fragile, wet or loosened subsoils combined with high wheel or track loads and contact pressures that create noticeable ruts in the topsoil. In-furrow ploughing increases this potential considerably by placing loads on the subsoil. Measures to avoid this potential involve a whole farm approach and an understanding of the many interactions between cropping systems and machinery. Alternatives to in-furrow ploughing that involve working from the surface and building a protective topsoil are discussed. Key measures to reduce the risk to subsoils involve a clear understanding of tyre load and inflation data and simple on-farm methods of achieving this are suggested. Although avoidance has the potential to reduce the risk, confinement of damage to specific strips in the field is seen as a realistic alternative. Controlled traffic operations, together with precision guidance, offer an economic means by which compaction on the cropped area can be avoided. The most effective route to improvement in soil care across the European Union (EU) is an appropriate management structure coupled with a best practice framework.  相似文献   
69.
An automatic flow procedure based on the multicommutation concept, comprising three-way solenoid valves, for the spectrophotometric determination of 3-hydroxybutyrate in animal serum and plasma is proposed. The 3-hydroxybutyrate was enzymatically converted to acetoacetate with the reduction of NAD+ to NADH monitored at 340 nm. It was possible to carry out up to 600 determinations without a significant decrease in the analytical signal, with 5 mg of 3-hydroxybutyrate dehydrogenase immobilized on porous silica beads and packed in a column. The system enabled 60 determinations/h of 3-hydroxybutyrate in the range of 10-150 mg L(-1), with a consumption of 0.9 mg of NAD+ and 200 microL of sample per determination. A detection limit of 2 mg L(-1) for both animal serum and plasma and coefficients of variation of 1.4% and 1.2% (n = 17), respectively, were determined. Animal serum and plasma samples were analyzed without previous treatment, the results of which agreed with those obtained using the conventional method (UV kit, Sigma).  相似文献   
70.
Muscadine (Vitis rotundifolia) grape juice was assessed for color and phytochemical stability as influenced by anthocyanin copigmentation with a water-soluble rosemary extract, fortification with ascorbic acid, and processing by heat or high hydrostatic pressure (HHP). The roles of polyphenolic cofactors in the presence and in the absence of ascorbic acid were assessed as a means to improve the overall processing stability of the juice. Addition of rosemary extract from 0 to 0.4% (v/v) readily formed copigment complexes with anthocyanins and resulted in concentration-dependent hyperchromic shifts from 10 to 27% that corresponded to increased antioxidant activity. The presence of ascorbic acid was generally detrimental to juice quality, especially in the presence of rosemary extract, and resulted in overall anthocyanin, ascorbic acid, and antioxidant activity losses. Although thermal and high-pressure processing methods were detrimental to juice quality, HHP resulted in greater losses after processing, likely due to action from residual oxidase enzymes. Although physicochemical attributes were enhanced by copigmentation with rosemary extract, methods to inactivate residual enzymes should be addressed prior to copigmentation to prevent degradation of anthocyanins in the presence of ascorbic acid.  相似文献   
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