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排序方式: 共有268条查询结果,搜索用时 15 毫秒
221.
222.
Chris de Bont Gert Jan Veldwisch Hans Charles Komakech Jeroen Vos 《Agriculture and Human Values》2016,33(3):641-654
This article contributes to the contemporary debate on land and water grabbing through a detailed, qualitative case study of horticultural agribusinesses which have settled in Tanzania, disrupting patterns of land and water use. In this paper we analyse how capitalist settler farms and their upstream and downstream peasant neighbours along the Nduruma river, Tanzania, expand and defend their water use. The paper is based on 3 months of qualitative field work in Tanzania. We use the echelons of rights analysis framework combined with the concept of institutional bricolage to show how this contestation takes place over the full spectrum of actual abstractions, governance and discourses. We emphasise the role different (inter)national development narratives play in shaping day-to-day contestations over water shares and rule-making. Ultimately, we emphasise that water grabbing is not a one-time event, but rather an on-going struggle over different water resources. In addition, we show how a perceived beneficial development of agribusinesses switching to groundwater allows them to avoid peasant-controlled institutions, avoiding further negotiation between the different actors and improving their image among neighbouring communities. This development illustrates how complex and obscured processes of water re-allocation can be without becoming illegal per se. 相似文献
223.
Branched-chain (iso and anteiso) fatty acids were isolated from marine sediments from several environments. The relatively high ratio of branched-chain to straight-chain fatty acids for the even-numbered carbon molecules suggests a bacterial origin for the branched-chain isomers. The branched-chain fatty acids are present in the Green River shale. Possible geochemical implications are suggested. 相似文献
224.
Roland WS Vincken JP Gouka RJ van Buren L Gruppen H Smit G 《Journal of agricultural and food chemistry》2011,59(21):11764-11771
The aim of this study was to identify the bitter receptor(s) that recognize the bitter taste of the soy isoflavone genistein. Screening of all 25 human bitter receptors revealed genistein as agonist of hTAS2R14 and hTAS2R39. Genistein displayed threshold values of 4 and 8 μM on hTAS2R14 and hTAS2R39 and EC(50) values of 29 and 49 μM, respectively. In addition, the behavior of structurally similar isoflavonoids was investigated. Although the two receptors are not closely related, the results for hTAS2R14 and hTAS2R39 were similar toward most isoflavonoid aglycones. By trend, threshold values were slightly lower on hTAS2R14. Glucosylation of isoflavones seemed to inhibit activation of hTAS2R14, whereas four of five glucosylated isoflavones were agonists of hTAS2R39, namely, glycitin, genistin, acetylgenistin, and malonylgenistin. A total of three hydroxyl substitutions of the A- and B-rings of the isoflavonoids seemed to be more favorable for receptor activation than fewer hydroxyl groups. The concentration of the trihydroxylated genistein in several soy foods exceeds the determined bitter receptor threshold values, whereas those of other soy isoflavones are around or below their respective threshold value. Despite its low concentration, genistein might be one of the main contributors to the bitterness of soy products. Furthermore, the bioactive isoflavonoids equol and coumestrol activated both receptors, indicating that their sensory impact should be considered when used as food ingredients. 相似文献
225.
Sundaresan NR Marcus Leo MD Subramani J Anish D Sudhagar M Ahmed KA Saxena M Tyagi JS Sastry KV Saxena VK 《Veterinary research communications》2009,33(1):49-56
Melatonin (N-acetyl-5-methoxytryptamine), an indole hormone, regulates various biological functions through three different receptor subtypes
(Mel-1a, Mel-1b, and Mel-1c). However, the distribution of different melatonin receptor subtypes in chicken reproductive tissues
was not known. In the present investigation, the partial sequences of ovarian melatonin receptor subtypes (Mel-1a, Mel-1b,
and Mel-1c) were characterized. Further, the expression profile of melatonin receptor subtypes in the granulosa and theca
layers of different preovulatory and postovulatory follicles (POF) were studied by semi-quantitative RT-PCR. The expression
of all three subtypes of melatonin receptors were observed in the ovary of domestic chicken. Analysis of partial sequences
of ovarian melatonin receptors revealed that the melatonin subtypes were identical to the brain receptors. In small white
ovary follicles, we observed only the expression of mel-1b receptors, but not mel-1a or mel-1c receptors. In yellow follicles,
all the three subtypes of receptors expression were noticed. Interestingly, we observed the expression of mel-1a receptor
only in thecal layer, but not in granulosa layer. In contrast, mel-1b and -1c receptors were expressed in both granulosa and
thecal layer. During the regression of POF, we observed significant upregulation of melatonin receptors (mel-1a and 1c) expression,
that downregulated in the later stages of regression. We assume that the expression of melatonin receptors might have been
influenced by the atresia or apoptosis of different follicular layers in POF. Our findings suggest that the differential distribution
of melatonin receptor subtypes might have distinct downstream cellular functions in the ovarian tissues. 相似文献
226.
Li Rui Zhao Zhuo Monfort W. Scott Johnsen Kyle Tse Zion T. H. Leo Donald J. 《Precision Agriculture》2021,22(3):1006-1018
Precision Agriculture - The southeastern states of the USA, namely Georgia, Florida and Alabama, account for two-thirds of the total peanut production in the USA. Determining the optimal harvest... 相似文献
227.
A bronchopleural fistula (BPF) consists of a direct communication between the bronchial tree and the pleural space, which can develop secondary to (pleuro) pneumonia. Thoracotomy has been reported as a viable treatment option in cases of nonresponsive pleuropneumonia, pleural abscess formation and necrotising pneumonia. The presence of a BPF can delay and even prevent healing of the thoracotomy site, with clinical signs of coughing and putrid purulent nasal discharge often seen. In this case report, we describe the diagnosis and localisation of a bronchopleural fistula using retrograde instillation of methylene blue through the thoracotomy site, followed by the successful closure of the BPF using endoscopic application of acrylate co-monomer glue (Glubran 2®). 相似文献
228.
D. Van Aken J. De Bont J. Vercruysse P. Dorny 《Tropical animal health and production》1990,22(4):231-238
Faecal egg counts were used to study patterns of nematode infestation of adult female goats and their offspring according to season, pregnancy and lactation or age on a goat farm (n = 2000) in north-western Sri Lanka. Average rainfall in the area is 825 mm and temperature is between 23 and 33 degrees C throughout the year. The only nematode species present on the farm were Haemonchus contortus and Oesophagostomum columbianum. In adult females the faecal egg output was not influenced by season and no significant periparturient rise was observed. In kids the egg counts rose from the third month of age onwards and reached the same levels as the adults by the fourth month. Post-mortem studies on a neighbouring farm indicated that hypobiosis was not present. 相似文献
229.
Ascorbic acid concentration in plasma, in amniotic and allantoic fluids, in the placenta and in 13 tissues of sheep fetuses and newborn lambs] 总被引:1,自引:0,他引:1
E Kolb M Wahren M Leo P Siebert J Erices L G?llnitz L V?lker 《DTW. Deutsche tier?rztliche Wochenschrift》1991,98(11):424-427
At each 8 on an average 92 (body weight 615 +/- 49 g) and 120 days (b.w. 1.8 +/- 0.40 kg) old fetuses as well as at 6 newborn lambs (b.w. 2.8 +/- 0.65 kg) the concentration of ascorbic acid in the plasma, in the amniotic- and allantois-fluid, in the fetal and maternal part of the placenta and in 13 tissues was analyzed. The highest concentration in the plasma (73 +/- 11 micrograms/ml) was determined in the newborns. The concentration in the amniotic-fluid decreased and that in the allantoic-fluid, the adrenals and the fetal part of the placenta increased in the course of growth. In the cerebrum, the cerebellum, the brain stem, the lungs, the heart, the kidneys, the M. longissimus and the M. semimembranosus the concentration diminished during the fetal growth. In the liver, the spleen and the pancreas the concentration was similar. The function of the ascorbic acid during the fetal development is discussed. The results are compared with those at human, pig and calf fetuses. In analyzing the ascorbic concentration in fetal body fluids of ungulates the high concentration of fructose as an influence-factor in the usual applied methods has to be considered. 相似文献
230.
Objective: To describe a standing laparoscopic ovariectomy technique with intraabdominal ovarian dissection inside a specimen retrieval bag for removal of large pathologic ovaries through small incisions. Study Design: Case series. Animals: Mares (n=43) aged 2–21 years and weighing 380–680 kg. Methods: Unilateral laparoscopic ovariectomy was performed on 43 standing sedated mares. Ovaries were approached via 3 portal sites, 2 in the paralumbar fossa and a 3rd between the 17th and 18th ribs on the ipsilateral side. Ovaries were dissected free using either a LiNA Tripol‐bipolar laparoscopic forceps or a Ligasure™ Vessel Sealing Device and removed by enlarging the proximal portal site ventrally using a grid technique. Use of a plastic specimen retrieval bag and cannula suction device facilitated intraabdominal dissection of very large ovaries into 2 or more pieces, before removal through small incisions. Results: Regardless of size, all ovaries were removed successfully through small incisions (range, 5–10 cm), with no major complications and an excellent cosmetic result. All sport horses returned to previous levels of work or higher, with 93% of breeding mares successfully bred in the 1st season after surgery. Conclusions: Large pathologic ovaries can be easily and safely removed by standing laparoscopic ovariectomy on the mare. Clinical Relevance: Standing laparoscopic ovariectomy combined with a small flank incision is a safe and highly effective technique for removal of large pathologic ovaries in the mare, negating the requirement for general anesthesia or large incisions. 相似文献