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1.
Acute liver failure was diagnosed in a 12-year-old cat. Fine needle aspirate cytology revealed high numbers of unsheathed microfilariae and a hepatocellular reaction with no evidence of bacterial infection. The microfilariae were identified as those of Dirofilaria repens by acid phosphatase staining. The high number of microfilariae seen in both the blood and the liver aspirate samples as well as the favourable response to ivermectin amongst other drugs administered, is suggestive that D. repens was the cause of the liver insult. A positive result obtained with an antigen-capture ELISA (Dirochek) for Dirofilaria immitis antigen was interpreted as false. This is the 1st report of Dirofilaria repens for South Africa.  相似文献   
2.
To define new grading rules, or to customize the ones in use in a rule-based automatic grading (RBAG) system of boards, is a time-consuming job for a sawmill engineer. This has the effect that changes are rarely made. The objective of this study was to continue the development of a method that replaces the calibration of grading rule settings by a holistic-subjective automatic grading, using multivariate models. The objective was also to investigate if this approach can improve sawmill profitability and at the same time have a satisfied customer. For the study, 323 Scots pine (Pinus sylvestris L.) boards were manually graded according to the preferences of an important customer. That is, a customer that regularly purchases significant volumes of sawn timber. This manual grading was seen as reference grading in this work. The same boards were also scanned and graded by a RBAG system, calibrated for the same customer. Multivariate models for prediction of board grade based on aggregated knot variables, obtained from the scanning, were calibrated using partial least squares regression. The results show that prediction of board grades by the multivariate models were more correct, with respect to the manual grading, than the grading by the RBAG system. The prediction of board grades based on multivariate models resulted in 76–87% of the boards graded correctly, according to the manual grading, while the corresponding number was 63% for the RBAG system.  相似文献   
3.
The forest planning system of large Swedish forest owners follows a three step procedure: long-term, medium-term, and short-term planning. The system is sequential and hierarchical in the sense that longer-term plans form the framework for shorter-term plans, and that top-level management prepares the long range plans and the lower management levels develop plans with successively shorter horizons. Studies indicate that this approach does not fully use existing knowledge within the organization. Problems associated with the top-down approach are also recognized in the general literature on organization and management. A proposal for a bottom-up approach is developed that aim at the use of local level knowledge to enhance accuracy and applicability of the forest plans. After top-level management has issued some fundamental planning directives, medium-term planning is conducted by the districts. Then the district plans are consolidated at the top-level for coordination and revision. A simulated planning process provides an illustration of the approach. The Heureka system is used here to optimize harvests and road costs with a mixed integer programming model of the problem, spanning 10 years with three seasons per year. The importance of detailed local knowledge to the outcome of planning is indicated, and needs for continued decision support systems development is discussed.  相似文献   
4.
Bone-metastasizing squamous-cell carcinoma of a 6-year-old female Bedlington terrier is reported. The dog was operated on for a squamous-cell carcinoma in the axillary region. Four weeks after operation the dog developed signs of anaemia. It also became weak and showed neurological signs. Radiographs revealed areas of rarefaction in two vertebrae and densities in the lungs suggesting tumour metastases. The animal was destroyed and metastases were found in the axillary and internal iliac lymph nodes, the lungs, the first thoracic vertebra and the third lumbar vertebra. The tumour mass in the thoracic vertebra protruded into the spinal canal and compressed the spinal cord. The tumour cells in the primary tumour were of anaplastic type. Résumé. Un carcinome squamo-cellulaire, métastasiant les os est rapporté chez un Bedlington terrier femelle de six ans. On a opéré le chien d'un carcinome squamo-cellulaire dans la région axillaire. Quatre semaines après l'opération le chien a développé des signes d'anémie. Il s'est aussi affaibli et a montré des signes neurologiques. Des radiographies ont révélé des surfaces de raréfaction dans deux vertèbres et les densités dans les poumons ont suggéré des métastases de tumeur. L'animal a été detruit et on a trouvé des métastases dans les n?uds lymphatiques, iliaques internes et axillaires, les poumons, la première vertèbre thoracique et la troisième vertèbre lombaire. L'excroissance dans la vertèbre thoracique a fait saillie dans le canal vertébral et a comprimé la moelle épinière. Les cellules de la tumeur dans la tumeur primaire étaient de type anaplastique. Zusammenfassung: Von einem Knochen-metastasierenden schuppenzelligem Karzinom in einem 6 Jahre alten weiblichen Bedlington-Terrier wurde berichtet. Man operierte den Hund an einem schuppenzelligen Karzinom in der Achsellymphdrüsengegend. Vier Wochen nach der Operation entwickelte der Hund Anzeichen von Anämie. Auch wurde er schwach und zeigte neurologische Symptome. Röntgenaufnahmen zeigten Gebiete von Rarefactio in zwei Rücken-wirbeln und Verdichtungen in der Lunge liessen auf Tochtergeschwulste deuten. Man tötete den Hund und Metastasen fanden sich in den Achsellymphdrüsen und den innerlichen Darmbein-lymphknoten, der Lunge, dem ersten Brustwirbel und dem dritten Lendenwirbel. Der Massen-tumor in dem Brustwirbel ragte bis in den Kanal der Wirbelsäule hinein und drückte auf denWirbelsäulenstrang. Die Tumorzellen in dem Primärtumor waren vom anaplastischen Typ.  相似文献   
5.
To investigate whether European whitefish (Coregonus lavaretus) groups in the brackish (≤7%) Gulf of Bothnia (Baltic Sea) express specific otolith elemental characteristics, concentrations of elements (Ca, Ba, Sr, Zn, Mn, Fe) in whole otoliths were studied by inductively coupled plasma‐optical emission spectrometry. Whitefish (N = 67) were sampled from six different latitudinal sites; four in the sea and two in rivers along the west coast of Finland, and from a fresh water lake for comparison. The concentration of several elements showed significant differences among sampling sites. Otolith Ba concentrations were higher at the northern sampling sites compared to the southern ones, thereby showing negative association to capture‐habitat salinity. In contrast, otolith Sr and Zn concentrations were lower at the northern sampling sites, thereby associating positively to capture‐habitat salinity. Otolith Mn concentrations did not associate with latitude or salinity but markedly varied between sampling sites. Elevated Fe concentrations occurred in fish otoliths from the two northernmost sites. Ca concentrations were at the same levels in otoliths from all whitefish samples. Otoliths of whitefish from the lake had very high Ba and low Sr concentrations compared to concentrations in otoliths from whitefish in the sea and rivers. Our results show that otolith elemental characteristics of whitefish vary considerably at various geographic scales showing high potential for population identification using elemental fingerprints. Analysis of otolith elemental characteristics may therefore provide an efficient tool for the identification of main areas of residence, spawning locations, and migration routes, thus contributing towards the sustainable management of whitefish stocks.  相似文献   
6.
This report describes bilateral mammary gland infection with a previously unidentified Cephalobus species of nematode. Only one previous case of verminous mastitis due to a Cephalobus species has been reported, pre-dating the widespread use of molecular diagnostics. This report describes the case presentation and management, as well as the morphological and molecular methods of nematode identification.  相似文献   
7.
Spirochetemia was diagnosed in 2 Siberian Huskies and a Rottweiler from the northwestern region of Texas between June 1999 and October 2001. Clinical findings were nonspecific; tick exposure was documented in 2 of the dogs. Hematologic abnormalities included anemia (n=2), neutrophilia (n=2, including 1 with a left shift), lymphopenia (n=3), eosinopenia (n=3), and thrombocytopenia (n=2). One anemic dog had a positive Coombs' test. In 1 dog, Western blot analysis of serum yielded multiple positive bands with B turicatae lysate, indicating the spirochetemia most likely was due to B turicatae infection. In 2 dogs, spirochetes were cultured from the blood and identified using DNA analysis as Borrelia turicatae; 1 of these dogs also was seropositive for Ehrlichia canis and B burgdorferi. In 2 cases, spirochetemia was more prominent in blood smears prepared immediately after sample collection than in smears prepared from EDTA blood. Two dogs recovered with doxycycline treatment; 1 dog declined clinically despite treatment and was euthanized. B turicatae is the agent of tick-borne (endemic) relapsing fever in humans and is distinct from B burgdorferi, the agent of Lyme disease; however, serologic cross-reactivity may occur. B turicatae is transmitted by the soft tick, Ornithodoros turicata, and infection should be considered in dogs with spirochetemia and possible exposure to the tick vector.  相似文献   
8.
Aerobic stability is an important feature in the evaluation of silages. The aims were to investigate the chemical and microbiological changes that occur in sugar-cane (Saccharum spp.) silage after aerobic exposure, to identify the major species of yeasts associated with the aerobic deterioration process and to select lactic acid bacteria (LAB) strains that can improve the aerobic stability of this silage. Fourteen wild LAB strains belonging to Lactobacillus plantarum, L. brevis and L. hilgardii were evaluated using experimental silos. Silage samples were collected at 0, 96 and 216 h after aerobic exposure to determinate the DM, WSC, pH, products of fermentation, to evaluate the silage temperatures and to identify yeast species associated with the aerobic deterioration of silage. The strains tested were able to modify the fermentative and chemical parameters and the diversity of yeasts species of silage after aerobic exposure. There was no association between the facultative or obligatory heterofermentative fermentation patterns and the increased aerobic stability of silage. Aerobic stability of sugar-cane silages was associated with high acetic acid and 1,2-propanediol concentrations. L. hilgardii UFLA SIL51 and UFLA SIL52 strains promoted an increase in aerobic stability of silage.  相似文献   
9.
Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon(C) contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid(0.6 g C/kg dry soil) were added to soils from three biotopes(grassland, fixed dune and mobile dune) located in Naiman, Horqin Sandy Land, Inner Mongolia, China) and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration(including that from the added substrates) was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical conductivity decreased in grassland  相似文献   
10.
The sawmill industry is a very important link in the Mozambique forest products value chain, but the industry is characterized by undeveloped processing technology and high-volume export of almost unrefined logs. The low volume yield of sawn timber has been identified as a critical gap in the technological development of the industry. To improve the profitability of the industry, there is thus a need to develop methods and techniques that improve the yield. In this paper, different positioning of logs prior to sawing and the possibility of increasing the volume yield of crooked logs by bucking the logs before sawing have been studied. A computer simulation was used to study the cant-sawing and through-and-through sawing of the logs to determine the volume yield of sawn timber from the jambirre (Millettia stuhlmannii Taub.) and umbila (Pterocarpus angolensis DC.) species. The optimal position, i.e. the position of the log before sawing that gives the highest volume yield of sawn timber for a given sawing pattern when the positioning parameters, offset, skew and rotation, are considered gave a considerable higher volume yield than the horns-down position. By bucking very crooked logs and using the horns-down positioning before sawing, the volume yield can be of the same magnitude as that obtained by optimal positioning on full-length (un-bucked) logs. The bucking reduces the crook of the logs and hence increases the volume yield of sawn timber.  相似文献   
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