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81.
A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen.  相似文献   
82.
In 1995, a peste des petits ruminants (PPR) outbreak was diagnosed in Ilam province in Iran near the border with Iraq both serologically and virologically. As then, despite all control measures, PPR has been identified in the whole country and has led to costs of at least US$1.5 million to the Iranian owners of sheep and goats.  相似文献   
83.
Rural development policies are often inspired by narratives that are difficult to challenge because they are based on an apparently obvious and coherent reading of reality. Research may confront such narratives and trigger debates outside the academic community, but this can have a feedback effect and lead to a simplistic or biased posture in research. This article analyzes a research-based initiative that questioned a commonly held narrative in large-scale irrigation schemes in Morocco concerning the structural weaknesses of farmer-led collective action. This initiative conceived an alternative narrative of farmer-led collective action, based on research and actions undertaken in collaboration with the farmers. The article assesses to what extent it was possible to design this narrative and to draw on it to orient research activities, actions with farmers and public engagement, without impairing the quality of the research process. The alternative narrative was designed and diffused based on three intertwined activities: (1) the identification and analysis of farmer-led collective actions, (2) the diffusion of information on successful farmer-led collective actions especially through the production of videos, and (3) exchanges with and between local farmers’ organizations. The alternative narrative that resulted from these activities emphasizes the potentialities of farmer-led collective action, and more broadly, the willingness and capabilities of many family farmers to play an active role in the governance of rural areas. The message of the alternative narrative and the distinction made between the research articles and videos in both their content and role ensured that research did not fall into simplistic or biased analyses. The alternative narrative also became a key to renewed relations between farmers and researchers and helped design training for students that pay more attention to local dynamics. In a situation in which scheme-level organizations show limited interest in reflexive enquiry, this initiative proposes some stepping stones to make it possible for changing narratives to accompany changing relations between actors.  相似文献   
84.
研究阳际峰自然保护区不同海拔梯度土壤剖面状况及其微生物学性状,探讨土壤微生物量C与N、酶活性、微生物商与呼吸速率的变化及其相互关系。结果发现,不同海拔梯度土壤在微生物学性状上均有较大差异。总的趋势是植被覆盖度高,地形平缓,土层厚,微生物活性强,且与海拔梯度呈显著正相关。在剖面分布上,也有明显的层次差异,即随土层的增加而减少。  相似文献   
85.
In the present study A. (T.) abortisuis isolated from pigs and bovines could be reliably identified by determination of phenotypic properties, genotypically by polymerase chain reaction with the help of A. (T.) abortisuis 16s-23S rDNA intergenic spacer region specific oligonucleotide primer and by Matrix-Assisted Laser Desorption Ionization-Time Of Flight mass spectrometry (MALDI-TOF MS). The latter appeared to be a promising tool for fast and cost effective identification of this species and might help to elucidate the role A. (T.) abortisuis plays in infections of pigs, bovines, possibly other animals or humans.  相似文献   
86.
87.
Twenty-five intact Barki lambs with mean body weight of 24.81 ± 0.16?kg were used to investigate the effect of including in the diet sugar beet pulp (SBP) treated biologically with Trichoderma reesei or chemically with urea 4 % on nutrients digestibility, growth performance, nitrogen (N) utilization, and hematological and biochemical parameters. Two experiments were conducted. In the growth experiment, five lambs were randomly assigned to one of five dietary treatments. Lambs were offered isonitrogenous and isoenergetic concentrate feed mixture containing on dry matter basis 0 % SBP (D0), 50 % SBP (D1), 50 % SBP treated with 4 % urea (D2), 50 % SBP treated with T. reesei (D3), and 25 % SPB treated with 4 % urea plus 25 % SPB treated with T. reesei (D4). In the metabolism experiment, five rams were used in a 5?×?5 Latin square design and housed in metabolism crates for 21?days. The present study showed that inclusion of SBP at the level of 50 % (D1) negatively affected diet digestibility coefficients of crude protein, crude fiber, and ether extract, in addition to average daily gain, feed conversion, and N utilization. However, treatment of SBP with urea (D2), T. reesei (D3), or the combination (D4) of both had improved (P?相似文献   
88.
The purpose of this study was to establish normal physiologic reference values for intraocular pressure (IOP) and Schirmer tear test (STT) results in clinically normal ostriches (Struthio camelus). Twenty ostriches of both sexes, 10 juveniles (1.5-2 yr of age) and 10 adults, were included in this study. Complete ophthalmic examination was performed prior to this investigation. STT was performed by inserting a standard sterile STT strip over the ventral lid margin into the ventral conjunctival sac for 60 sec. Following the STT, IOP was measured using applanation tonometry with the Tono-Pen Vet tonometer after topical instillation of one drop of 0.5% proparacaine ophthalmic solution. The mean +/- SD and range of Tono-Pen readings of IOP for all birds was 18.8 +/- 3.5, with a range of 12-24. Mean IOP in juvenile ostriches was 19.7 +/- 3.6. Mean IOP in adult ostriches was 16.9 +/- 2.9. There was no statistically significant difference between young and adult birds (P = 0.07). The mean STT values in the present study were 16.3 +/- 2.5 mm/1 min when measurements from both eyes were averaged. Mean STT in juvenile and adult ostriches was 15.4 +/- 1.8 and 17.2 +/- 2.9 mm/1 min, respectively. There was no statistically significant difference between young and adult birds (P = 0.11). No statistically significant differences between genders were found for any of the results (P > or = 0.41). In conclusion, this study provides normal reference range values for STT and IOP in clinically healthy ostriches.  相似文献   
89.
Background: Spinal cord has a limited capacity to repair; therefore, medical interventions are necessary for treatment of injuries. Transplantation of Schwann cells has shown a great promising result for spinal cord injury (SCI). However, harvesting Schwann cell has been limited due to donor morbidity and limited expansion capacity. Furthermore, accessible sources such as bone marrow stem cells have drawn attentions to themselves. Therefore, this study was designed to evaluate the effect of bone marrow-derived Schwann cell on functional recovery in adult rats after injury. Methods: Mesenchymal stem cells were cultured from adult rats’ bone marrow and induced into Schwann cells in vitro. Differentiation was confirmed by immunocytochemistry and RT-PCR. Next, Schwann cells were seeded into collagen scaffolds and engrafted in 3 mm lateral hemisection defects. For 8 weeks, motor and sensory improvements were assessed by open field locomotor scale, narrow beam, and tail flick tests. Afterwards, lesioned spinal cord was evaluated by conventional histology and immunohistochemistry. Results: In vitro observations showed that differentiated cells had Schwann cell morphology and markers. In this study, we had four groups (n = 10 each): laminectomy, control, scaffold and scaffold + Schwann cells. Locomotor and sensory scores of cell grafted group were significantly better than control and scaffold groups. In histology, axonal regeneration and remyelination were better than control and scaffold groups. Conclusion: This study demonstrates that bone marrow-derived Schwann cells can be considered as a cell source for Schwann cells in SCI treatment. Key Words: Rats, Spinal cord injuries (SCI), Bone marrow, Schwann cells, Cell transdifferentiation  相似文献   
90.
Background : Oocyte cryopreservation is one of the most important topics in the field of assisted reproductive technology to preserve women fertility, but relationship between cryopreservation and apoptosis is still a matter of debate. The present study was aimed to investigate the effects of vitrification on apoptosis in mouse oocytes by Cryotop method. Method: A total of 200 germinal vesicle (GV) and 200 metaphase II (MII) oocytes were obtained from ovaries and fallopian tubes of NMRI mice, respectively and divided into control and experimental groups. Oocytes in experimental group were vitrified by Cryotop using vitrification medium and were kept in liquid nitrogen for one month. The survival rate of oocytes was evaluated after 2 hour incubation time. Then, the oocyte apoptosis was evaluated by TUNEL technique and compared with those in control group. The data was compared statistically using SPSS software and chi-square test. Results: The survival rates of vitrified GV (93%) and MII oocytes (88%) showed a significant decrease compared with the control group (P<0.05), but there was no significant difference in survival rate of both vitrified oocyte groups. The incidence of apoptosis in vitrified and control GV oocytes showed no significant difference (13% vs. 7%), but the rate of apoptosis in vitrified MII oocytes increased significantly not only in comparison with MII control group (25% vs. 5%) but also with vitrified GV oocytes (P<0.05). Conclusion: The results indicate that vitrification increases apoptosis in mouse MII oocytes and apoptosis may play a role in MII oocyte injury after vitrification. Key Words: Vitrification, Apoptosis, Oocytes  相似文献   
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