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81.
One of the major tasks of experimental farms is the determination of productivity with regard to the regionally differing natural, technological, and socio-economic boundary conditions. In order to achieve this aim the location of the respective stations must be regionally representative from the viewpoint of the major factors controlling agrarian production. In paradigmatic representation, i.e. focusing the very interest on soil qualities and dealing with the north-eastern part of Ghana as a developing country, this article describes a cogent method for defining local representativity of production sites by means of classification procedures and biplot calculus. The application of the latter derivative of matrix calculus appears absolutely necessary for defining those results of clustering procedures which are interpretable in factual terms.  相似文献   
82.
The RSPO and RTRS are global private partnerships that have been set up by business and civil society actors from the North to curb de-forestation and to promote sustainable production of palm oil or soy in the South. This article is about the launch of new national standards in Indonesia and Brazil that are look-alikes of the global standards but have been set up and supported by government or business actors from the South. The two main questions of this article are: do the new national standards in Indonesia and Brazil provide a fundamental challenge to the RSPO and RTRS, or do they demonstrate the successful diffusion and adoption of global private rules into national contexts? Do the new national standards help or undermine the RSPO and RTRS in their efforts to reduce de-forestation? Combining the theoretical notions of proto-institution and rival governance network, a comparative analysis is offered of the launch of the new national standards in Indonesia and Brazil. The conclusion is that, whilst the RSPO and RTRS have served as models for the general design and principles of the national standards, they really differ from the global standards in terms of normative contents: the national standards offer more room to palm oil plantations and large-scale soy producers to expand production at the expense of forests and other high conservation areas. Governments and producer associations in Indonesia and Brazil have not launched national standards to implement the RSPO or RTRS but to challenge these interventions from the North.  相似文献   
83.
Antioxidant enzyme activities and glutathione status were determined in different tissues of two teleost species, the rainbow trout (Oncorhynchus mykiss) and the black bullhead (Ameiurus melas) to establish whether age-related changes exist between mature and immature individuals. Glutathione reductase and superoxide dismutase activities were significantly lower in hepatic and extrahepatic tissues of 3+ year than 1+ year trout and bullheads. Activities of glutathione peroxidase, catalase and glutathione S-transferase did not exhibit a clear pattern, with decreases in liver and kidney, but increases in gill and muscle tissues. Glutathione concentrations were significantly higher in most tissues of 3+ year than in 1+ year trout, but remained unchanged or decreased in tissues of older bullheads. The results imply an age- or maturation-dependent effect on key antioxidant enzymes in various tissues of these 2 teleost species. Thus, age and maturation may impact upon the use of oxidative stress parameters as indicators of contaminant exposure in environmental studies.  相似文献   
84.
OBJECTIVE: To develop a minimally invasive, hand-assisted laparoscopic ovariohysterectomy (HALS-OHE) technique in the mare and to evaluate safety and any associated complications. STUDY DESIGN: Experimental study. ANIMALS: Eight, 11-24-year-old mares with anatomically normal urogenital tracts. METHODS: The surgical technique was developed in 2 non-survival mares and subsequently evaluated in 6 survival procedures. Food was withheld for 48 hours, then mares were anesthetized and positioned in dorsal recumbency for laparoscopic surgery. A hand access device (Omniport) was placed followed by 4 laparoscopic portals. Transection of the ovarian pedicles and broad ligaments was achieved using a combination of a laparoscopic stapling instrument (Endo GIA II), an ultrasonically activated instrument (Harmonic Scalpel), and endoscopic clips (Endo Clip II ML). The genital tract was exteriorized through the laparotomy, and the uterus transected and sutured in a conventional pattern. Horses were evaluated through postoperative day 14 when a necropsy was performed. RESULTS: Four mares recuperated well after surgery, 1 mare was euthanatized because of bilateral femur fracture during anesthetic recovery, and another developed severe pleuropneumonia. At necropsy all but 1 abdominal incision was healing routinely. One mare had abscessed along the celiotomy incision and developed visceral adhesions. Uncomplicated healing of transected mesovarial, mesometrial, and uterine remnants was observed. CONCLUSIONS: Ovariohysterectomy in horses can be accomplished using HALS technique. CLINICAL RELEVANCE: HALS-OHE technique represents a minimally invasive and technically feasible alternative for conventional OHE. Careful patient selection and preparation may reduce the complications observed. The HALS technique may be useful in other laparoscopic surgical procedures.  相似文献   
85.
This paper describes the accumulation pattern of 42 mineral elements in Vitis vinifera L. berries during development and ripening and their distribution in berry skin, seeds, and flesh around harvest time. Grape berries were sampled in two different vineyards with alkaline soil and analyzed using a ICP-MS. Although elemental amounts were significantly different in the grapes from the two vineyards, the accumulation pattern and percentage distribution in different parts of the berries were generally quite similar. Ba, Eu, Sr, Ca, Mg, Mn, and Zn accumulate prior to veraison. Al, Ce, Dy, Er, Ga, Gd, Ho, La, Nd, Pr, Sm, Sn, Zr, Th, Tm, U, Y, and Yb accumulate mainly prior to veraison but also during ripening. Ag, As, B, Cd, Cs, Cu, Fe, Ge, Hg, K, Li, Na, P, Rb, Sb, Se, and Tl accumulate progressively during growth and ripening. With regard to distribution, Ba, Ca, Eu, Fe, Mn, P, Sr, and Zn accumulate mainly in the seeds, Al, B, Ga, Sn, and the rare earths analyzed, except for Eu, accumulate mainly in the skin, and Ag, As, Cd, Cs, Cu, Ge, Hg, K, Li, Mg, Na, Rb, Sb, Se, Th, Tl, U, and Zr accumulate mainly in the flesh. A joint representation of the accumulation and distribution patterns for the elements in the berry is also given.  相似文献   
86.
87.
Objective: To determine the effect of gastrointestinal (GI) decontamination on the incidence of prolonged prothrombin time (PT) in dogs after anticoagulant rodenticide ingestion. Design: Retrospective study. Setting: Urban emergency room. Animals: One hundred and fifty‐one client‐owned dogs. Measurements: Dogs presented to the emergency room within 6 hours of ingestion of an anticoagulant rodenticide and had a PT measured within 2–6 days of toxicant ingestion before initiating vitamin K therapy were included. Dogs were categorized as treated or untreated based on the institution of vitamin K therapy following PT testing. The signalment, body weight, type of rodenticide ingested, time elapsed between ingestion and initial presentation, method(s) of GI decontamination, and the times elapsed between both toxicant ingestion and initial hospital presentation until determination of PT were recorded. The PT results were recorded as well as any treatment received following the recheck examination. Any reported incidents of bleeding or untoward effects between exposure and reexamination were recorded. Main results: Of 151 dogs, only 11 dogs (8.3%) developed prolonged PT requiring vitamin K supplementation. None of the 11 dogs with prolonged PTs exhibited signs of bleeding or required transfusion therapy. No differences in age, weight, or time elapsed between treated and untreated patients were found. Conclusions: The incidence of prolonged PT is low in dogs receiving GI decontamination within 6 hours of anticoagulant rodenticide ingestion. Delaying vitamin K therapy until a PT has been assessed 48–72 hours after initial exposure appears to be safe and sensitive in dogs following anticoagulant rodenticide ingestion.  相似文献   
88.
OBJECTIVE: To document the clinical, clinicopathologic, and pathologic findings in cats with severe sepsis, identify abnormalities unique to this species, and identify criteria that could be used antemortem to diagnose the systemic inflammatory response syndrome in cats. DESIGN: Retrospective study. ANIMALS: 29 cats confirmed to have severe sepsis at necropsy. PROCEDURE: Pertinent history, physical examination findings, and results of hematologic and biochemical testing were extracted from medical records. RESULTS: Clinical diagnoses included pyothorax, septic peritonitis, bacteremia secondary to gastrointestinal tract disease, pneumonia, endocarditis, pyelonephritis, osteomyelitis, pyometra, and bite wounds. Physical examination findings included lethargy, pale mucous membranes, poor pulse quality, tachypnea, hypo- or hyperthermia, signs of diffuse pain on abdominal palpation, bradycardia, and icterus. Clinicopathologic abnormalities included anemia, thrombocytopenia, band neutrophilia, hypoalbuminemia, low serum alkaline phosphatase activity, and hyperbilirubinemia. Necropsy findings included multi-organ necrosis or inflammation with intralesional bacteria. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that severe sepsis in cats is characterized by lethargy, pale mucous membranes, signs of diffuse abdominal pain, tachypnea, bradycardia, weak pulses, anemia, hypoalbuminemia, hypothermia, and icterus. Recognition of this combination of clinical findings should facilitate the diagnosis of severe sepsis in cats.  相似文献   
89.
A mixed infection with rotavirus and 3 different Campylobacter jejuni strains was analysed in Caco-2 cells, a cell line highly susceptible to these pathogens. The results obtained showed no influence of the virus preinfection on the Campylobacter jejuni adhesion or internalisation in Caco-2 cells. Confocal laser scanning microscopy of mixed infected cells confirmed these results. The data from the present study indicate that specific rather than nonspecific mechanisms are involved in the interaction between rotavirus, campylobacter and host cells.  相似文献   
90.
The distribution of fitness effects (DFE) of mutations is of fundamental importance for understanding evolutionary dynamics and complex diseases and for conserving threatened species. DFEs estimated from DNA sequences have rarely been subject to direct experimental tests. We used a bacterial system in which the fitness effects of a large number of defined single mutations in two ribosomal proteins were measured with high sensitivity. The obtained DFE appears to be unimodal, where most mutations (120 out of 126) are weakly deleterious and the remaining ones are potentially neutral. The DFEs for synonymous and nonsynonymous substitutions are similar, suggesting that in some genes, strong fitness constraints are present at the level of the messenger RNA.  相似文献   
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