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21.
The present study examines the long-term productivity growth and sustainability of Greek irrigated agriculture. A log linear trend model was used to measure long-term productivity growth, and the total factor productivity (TFP) approach measures the sustainability of the irrigated production system. A time series database of inputs and outputs data were used for the production period of 1961?–?2001 (41 years) which revealed that there is an increasing trend in the irrigated area of the country. The annual growth rate of the irrigated area is 2.6% during this time period. The long-term trends in yields of crops grown in irrigated agriculture are positive. Fertilizer use rate per ha sharply increases during this period. The productivity of irrigated Greek agriculture also increases over the time period as a result of the introduction of High Yielding Variety (HYV), seed, fertilizer and water technology. The measurement of TFP indices indicates that the long-term trend in productivity growth of irrigated Greek agricultural system is positive. The result implies that the irrigated Greek agricultural production system has long-term sustainability. The result also indicates that fertilizer, fixed capital, rainfall and temperature are positively contributing to the mean production of Greek irrigated agriculture. On the other hand, pesticide, labour and fixed capital reduces variability of irrigated agriculture. To this end, long-term agricultural sustainability depends on patterns of input use.  相似文献   
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New Forests - Eucalyptus harvests generate residues that remain on the soil and affect the efficacy of preemergent herbicides in the following planting cycle. The objective of this work was to...  相似文献   
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Objective To develop a simple and effective surgical technique for third‐compartment cannulation in alpacas. Design Prospective study using six adult male alpacas. Methods General anaesthesia was induced and a polyurethane gastrostomy tube was surgically implanted into the distal portion of the third compartment. Results Three of the alpacas retained their cannulas for a 100‐day period; however, three cannulas were dislodged during the study. Two of the three dislodged cannulas were replaced during a second surgical procedure. Cannulas were well tolerated by the alpacas and all animals remained clinically healthy during the study period. Third compartment contents did not leak from the cannulation site. The tubes were manually removed following the completion of the study and the small defect in the body wall quickly healed over in all animals. Conclusion Surgical placement of polyurethane tubes designed for percutaneous endoscopic gastrostomy is a useful method of cannulating the third compartment in camelids. This technique can be used for experimental studies and possibly could be used for nutritional support and fluid therapy in sick camelids that might need long‐term care.  相似文献   
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AIM: To study the molecular mechanism of Chinese medicine formula Bushen Bugu Tang (BSBGT) for the treatment of postmenopausal osteoporosis (PMO). METHODS: Forty female SD rats were divided into four groups: the sham group, OVX group, estrogen treatment group and BSBGT treatment group, ten for each, difference operation and treatment were given. Subsequently, bone mineral density (BMD), bone histomorphometric changes and collagen type I expression in the femur of these rats were examined. In order to position the target of the formula acting on bone, the effect of BSBGT on regulation of mRNA levels of RANKL and OPG, two key factors for regulating osteoclastogenesis, by using rat calvarial-derived stromal cell cultrues, was elucidated. RESULTS: The BSBGT formula was found as effective as estrogen in preventing the reduction of BMD, the trabecular area and trabecular numbers in femora and also the decrease in collagen type I expression following ovariectomy. RT-PCR resulted showed that both estrogen and BSBGT significantly up-regulated OPG mRNA level and down-regulated RANKL mRNA level, resulting in an increased ratio of OPG/RANKL in cultured rat stromal cells. CONCLUSIONS: The ratio of OPG/RANKL within the osseous environment determines whether bone formation predominates bone resorption. We therefore concluded that the BSBGT formula might be as effective as estrogen in prevention of postmenopausal osteoporosis through the mechanism of up-regulating RANKL expression and down-regulating OPG expression in osteoblast/stromal cells.  相似文献   
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The present study was conducted to examine the effect of high heparin concentration on capacitation of buffalo spermatozoa with a short incubation time. Frozen thawed spermatozoa from three buffalo bulls were pooled and treated with either 50, 100 or 200 microg/ml heparin for 30 min. Capacitation was evaluated by acrosome reaction of spermatozoa and in vitro fertilization rate (per cent cleavage rate, per cent cleavage index). Acrosome reaction was induced in heparin treated spermatozoa with calcium ionophore A23187 and staining was carried out with Coomassie G-250 to evaluate the response as compared with control (0 heparin + calcium ionophore). Significantly higher percentage of acrosome reaction (AR) spermatozoa was noted after heparin treatment (36.8-48.2%) as compared with control (8.1% ; p < 0.05) but differences among the three heparin concentrations were non-significant. However, a significantly higher in vitro fertilization rate was recorded in spermatozoa capacitated by 50 and 100 microg/ml heparin (80.4 and 75.9% cleavage rate, respectively) as compared with 200 microg/ml heparin (47.2% cleavage rate; p < 0.001). It is concluded that buffalo spermatozoa capacitated with 50-100 microg/ml heparin had significantly higher ability to improve in vitro fertilization rate in buffalo.  相似文献   
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Bats are essential to the global ecosystem, but their ability to harbour a range of pathogens has been widely discussed, as well as their role in the emergence and re‐emergence of infectious diseases. This paper describes the first report of coinfection by two zoonotic agents, rabies virus (RABV) and the fungus Histoplasma suramericanum in a bat. The bat was from the Molossus molossus species, and it was found during the daytime in the hallway of a public psychiatric hospital in a municipality in São Paulo State, southeastern Brazil. RABV infection was diagnosed by the direct fluorescent antibody test and mouse inoculation test. The fungus was isolated by in vitro culture. Both diagnoses were confirmed by molecular techniques. Phylogenetic analysis showed that the fungus isolate had proximity to H. suramericanum in the Lam B clade, while the RABV isolate was characterized in the Lasiurus cinereus lineage. Since the M. molossus bat was found in a peri‐urban transition area (urban/peri‐urban), the possibility of cross‐species transmission of this RABV lineage becomes more plausible, considering that this scenario may provide shelter for both M. molossus and L. cinereus. These are relevant findings since there has been an increase in bat populations in urban and peri‐urban areas, particularly due to environmental modifications and anthropogenic impacts on their habitat. Thus, the detection of two zoonotic agents in a bat found in a public hospital should raise awareness regarding the importance of systematic surveillance actions directed towards bats in urban areas.  相似文献   
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The provision of analgesia at the time of marking has been adopted by the Australian sheep industry, but data on production benefits are lacking. In the current study, alternate lambs were provided with either meloxicam (non‐steroidal anti‐inflammatory drug [NSAID], n = 781) or no analgesia (NONE, n = 822) at the time of ring castration and tail docking. Six distinct management groups of lambs were studied. Lambs were weighed immediately before marking and then again at weaning. There was no significant effect of treatment on average daily gain between marking and weaning in cross‐bred lambs. In Merino lambs, average daily gain was 5 g/day lower (P < 0.005) in lambs receiving NSAID, but this may not be biologically significant. Lamb losses were significantly (P < 0.05) lower in the NSAID group (1.1%) than in the NONE group (2.7%). This observation is worth validating in larger studies, particularly considering that lamb mortality is a significant cost to production and welfare concern.  相似文献   
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