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61.
Glucose, fructose, sucrose, free asparagine, and free glutamine were analyzed in 74 potato samples from 17 potato cultivars grown in 2002 at various locations in Switzerland and different farming systems. The potential of these potatoes for acrylamide formation was measured with a standardized heat treatment. These potentials correlated well with the product of the concentrations of reducing sugars and asparagine. Glucose and fructose were found to determine acrylamide formation. The cultivars showed large differences in their potential of acrylamide formation which was primarily related to their sugar contents. Agricultural practice neither influenced sugars and free asparagine nor the potential of acrylamide formation. It is concluded that acrylamide contents in potato products can be substantially reduced primarily by selecting cultivars with low concentrations of reducing sugars.  相似文献   
62.
This paper analyzes the possibilities and challenges of Fair Trade certification as a movement seeking to improve the well-being of small-scale coffee growers and coffee laborers in the global South. Six months of fieldwork was conducted in 2005–2006 to study the roles of a wide range of farmers, laborers, cooperative administrators, and export companies in Fair Trade coffee production and trade in Nicaragua. The results of our evaluation of the ability of Fair Trade to meet its objectives indicate that Fair Trade’s opportunities to provide a significant price premium for participating farmers largely depend on world coffee prices in mainstream markets. While Fair Trade has promoted premiums for social development for participating producers and strengthened the institutional capacities of the cooperatives involved, its ability to enhance significantly the working conditions of hired coffee laborers remains limited.  相似文献   
63.
The purpose of this study was to establish a minimal invasive, transendoscopic technique for injection of poly-L-lactic acid into the free edge of the soft palate that can be performed on the standing sedated horse. Furthermore, whether the implant material induces an increase in fibrous tissue at the injection site, resulting in a greater rigidity of the soft palate, was determined.In 4 horses, the injection was performed bilaterally along the caudal margin of the soft palate, and the influence of the treatment on the soft palate function was determined. Clinical, radiographic and endoscopic examinations at rest were performed before and up to 168 days after injection according to a standardized examination protocol.In 6 horses, the implant material was injected unilaterally into the right half of the caudal margin of the soft palate. After clinical and endoscopic follow-up examinations, 2 horses each were killed 28, 84, and 168 days after the implantation procedure. At necropsy, macroscopic comparison of the treated and the untreated halves of the soft palate showed the influence on the size of the ostium intrapharyngeum and on the soft palate thickness. The localization of the implant material in the soft palate and the tissue response to the poly-L-lactic acid were evaluated histologically.Transendoscopic injection into the soft palate requires neither general anesthesia nor wound management, and it is noted for minimal tissue trauma. After injection, no alteration of the soft palate function was observed in horses with normal upper airway mechanics. One horse with intermittent dorsal displacement of the soft palate showed an improvement of the soft palate function for 112 days after implantation. No significant alteration in the size of the ostium intrapharyngeum was evident in any horse. Histologic assessment indicated the presence of implant material during the entire observation period of 168 days. The implant was accompanied by a granulomatous inflammation, and it was encapsulated by fibrous tissue. This may result in an increase in stiffness, and subsequent a greater rigidity of the soft palate, preventing it from displacement. The injection may therefore be considered an alternative to established therapies in horses showing dorsal displacement of the soft palate because of its unstable free edge.  相似文献   
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65.
Caprine coccidiosis, affecting mainly young goat kids around the weaning period, is worldwide the most important disease in the goat industry. Control of caprine coccidiosis is increasingly hampered by resistances developed against coccidiostatic drugs leading to an enhanced need for anticoccidial vaccines. In the current study we conducted an oral immunization trial with live attenuated sporulated Eimeria ninakohlyakimovae oocysts. Sporulated E. ninakohlyakimovae oocysts were attenuated by X-irradiation technique. The experimental design included a total of 18 goat kids divided into the following groups: (i) animals immunized with attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-irradiated homologous oocysts (group 1); (ii) animals infected with non-attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-attenuated homologous oocysts (group 2); (iii) animals primary-infected with untreated E. ninakohlyakimovae oocysts at 8 weeks of age (control of the challenge infection, group 3); (iv) non-infected control animals (group 4). Goat kids immunized with live attenuated E. ninakohlyakimovae oocysts (group 1) excreted significantly less oocysts in the faeces (95.3% reduction) than kids infected with non-attenuated ones (group 2). Furthermore, immunization with live but attenuated oocysts resulted in ameliorated clinical coccidiosis compared to goat kids infected with untreated oocysts (group 2) and resulted in equally reduced signs of coccidiosis after challenge infection compared to acquired immunity driven by non-attenuated oocysts. Overall, the present study demonstrates for the first time that live attenuated E. ninakohlyakimovae oocysts orally administered showed almost no pathogenicity but enough immunogenicity in terms of immunoprotection. Importantly, vaccinated animals still shed low amounts of oocysts, guaranteeing environmental contamination and consecutive booster infections to sustain ongoing immunity.  相似文献   
66.
Cows with different Insulin-like Growth Factor-I (IGF-I) concentrations showed comparable expression levels of hepatic growth hormone receptor (GHR). Suppressor of cytokine signaling 2 (SOCS2), could be responsible for additional inhibition of the GHR signal cascade. The aims were to monitor cows with high or low antepartal IGF-I concentrations (IGF-Ihigh or IGF-Ilow), evaluate the interrelationships of endocrine endpoints, and measure hepatic SOCS2 expression. Dairy cows (n = 20) were selected (240 to 254 days after artificial insemination (AI)). Blood samples were drawn daily (day -17 until calving) and IGF-I, GH, insulin, thyroid hormones, estradiol, and progesterone concentrations were measured. Liver biopsies were taken (day 264 ± 1 after AI and postpartum) to measure mRNA expression (IGF-I, IGFBP-2, IGFBP-3, IGFBP-4, acid labile subunit (ALS), SOCS2, deiodinase1, GHR1A). IGF-I concentrations in the two groups were different (p < 0.0001). However, GH concentrations and GHR1A mRNA expression were comparable (p > 0.05). Thyroxine levels and ALS expression were higher in the IGF-Ihigh cows compared to IGF-Ilow cows. Estradiol concentration tended to be greater in the IGF-Ilow group (p = 0.06). It was hypothesized that low IGF-I levels are associated with enhanced SOCS2 expression although this could not be decisively confirmed by the present study.  相似文献   
67.
Direct observation of the detailed conformational fluctuations of a single protein molecule en route to its folded state has so far been realized only in silico. We have used single-molecule force spectroscopy to study the folding transitions of single calmodulin molecules. High-resolution optical tweezers assays in combination with hidden Markov analysis reveal a complex network of on- and off-pathway intermediates. Cooperative and anticooperative interactions across domain boundaries can be observed directly. The folding network involves four intermediates. Two off-pathway intermediates exhibit non-native interdomain interactions and compete with the ultrafast productive folding pathway.  相似文献   
68.
beta-Secretase plays a critical role in beta-amyloid formation and thus provides a therapeutic target for Alzheimer's disease. Inhibitor design has usually focused on active-site binding, neglecting the subcellular localization of active enzyme. We have addressed this issue by synthesizing a membrane-anchored version of a beta-secretase transition-state inhibitor by linking it to a sterol moiety. Thus, we targeted the inhibitor to active beta-secretase found in endosomes and also reduced the dimensionality of the inhibitor, increasing its local membrane concentration. This inhibitor reduced enzyme activity much more efficiently than did the free inhibitor in cultured cells and in vivo. In addition to effectively targeting beta-secretase, this strategy could also be used in designing potent drugs against other membrane protein targets.  相似文献   
69.
70.
  1. The conservation of marine megafauna presents numerous difficulties owing to their high mobility over difficult-to-access oceanic areas that impairs the collection of basic, but essential, biological information.
  2. The Bryde's whale (Balaenoptera edeni) is one of the most elusive species of baleen whales, and although it is known to be a seasonal visitor to several archipelagos in Macaronesia (the Azores, Madeira, and Canaries), there are no studies regarding its occurrence or geographical connectivity in this area of the Atlantic.
  3. A 14-year photographic database was used to determine short-term (intra-seasonal) and long-term (inter-annual) Bryde's whale site fidelity and to estimate individual residency times in Madeira, whereas photographic catalogues from Madeira and the Canaries were compared in order to assess large-scale movements (i.e. on the scale of hundreds of kilometres).
  4. In Madeira, 59 individuals were identified, 27 (45.8%) of which were recaptured. Of these, 10 individuals (37.0%) presented short-term site fidelity and 17 individuals (63.0%) presented long-term site fidelity, with a maximum recapture interval of 12 years. Lagged identification rates showed that five individuals (SE = 2) remained in the area for 32 days (SE = 108 days) before leaving and not returning during the same year. Seven individuals were seen both in Madeira and the Canaries (catalogue comprising 51 individuals), three of which were identified multiple times in both archipelagos, with a minimum of 43 days between consecutive sightings.
  5. This information combined with the fact that this species is commonly sighted accompanied by calves and feeding in both archipelagos highlights the ecological importance of this area for Bryde's whales. This should be taken into consideration by policymakers when implementing conservation measures, where coordination of effort among countries is needed. This study also reinforces the value of using data from platforms of opportunity and of making photographic data open access.
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