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101.
Six cats with chronic progressive neurologic signs of ataxia, paresis, tremors, pupillary abnormalities and seizures had polioencephalomyelitis of probable viral origin. Lesions were most severe in the spinal cord. The uniformity in distribution and nature of the lesions in all six cats strongly suggested a common cause. The condition was compared with other viral infections of known and unknown cause. 相似文献
102.
F. Kristensen B. Kristensen M. Vandevelde R.J. Higgins A.L. De Weck 《Veterinary immunology and immunopathology》1981,2(6):579-590
Lymphocytes from dog thymus and mesenteric lymphnodes have been stimulated in vitro with 3 different mitogens. Culture medium was enriched with either autologous plasma, fetal calf serum or a newly described defined serum substitute. In such cultures the number of surviving and activated cells was quantified by cytofluorometry and the proliferation was assessed by thymidine incorporation. Results obtained with the 3 media were very similar. A significant number of lymphocytes died during the first 42 hours of incubation. There was a tendency toward more surviving cells with fetal calf serum and the serum substitute, whereas more activated (G1) cells and higher thymidine incorporation could be observed with autologous plasma. Furthermore, when results obtained with various mitogen concentrations and from individual dogs were analyzed, a high correlation between “highly activated (G1b) cells and thymidine incorporation was found, i.e. r=0.84 for thymocytes and 0.68 for lymphnode cells. The correlation between all G1 (G1a+b) cells and thymidine incorporation was lower or absent (r=0.02 and 0.55, respectively). It is concluded from these results that the population of G1b cells have received all required signals necessary for proliferation whereas the total G1 cell population also include activated cells, which are not obligatorily undergoing subsequent proliferation 相似文献
103.
104.
B. Kristensen F. Kristensen M. Vandevelde R.J. Higgins A.L. de Weck 《Veterinary immunology and immunopathology》1982,3(4):439-448
Lymphocytes from dog peripheral blood have been stimulated in vitro with 3 different mitogens (Con A, PHA and PWM). Culture medium was RPMI 1640 enriched with either autologous plasma, fetal calf serum or a newly described defined serum substitute. In such cultures the number of surviving and activated cells was measured by cytofluorometry and the proliferation was assessed by thymidine incorporation. In unstimulated cultures, up to 70% of all cells had disappeared (died) during the first 42 hours of incubation, whereas the number of viable cells was reduced to 50–60% in mitogen stimulated cultures. Of the surviving lymphocytes, between 25–40% of the cells appeared to have an elevated RNA-content (activated or G1 cells). By comparison between thymidine incorporation and number of mitogen induced G1 cells, a very high correlation was found (r=0.92). However, the slope of the regression line was much lower than expected. The low thymidine incorporation per activated cell was primarily related to the high cell death and a resulting dilution of tritiated thymidine. Indeed, preliminary results suggested that the same thymidine incorporation per G1b cells could be obtained if peripheral blood lymphocytes were washed immediately before pulsing as could be obtained with lymphnode cells without washing. 相似文献
105.
106.
Osteoarthritis (OA) is one of the most common chronic musculoskeletal diseases and causes of lameness in the dogs. The osteoarthritic disease process involves the entire synovial joint, encompassing the synovium, cartilage and underlying bone. Joint failure results from an abnormal mechanical strain causing damage to normal tissue or failure of pathologically impaired articular cartilage and bone under the influence of normal physiological strain or a combination of both. In both cases, the end point is cartilage loss and joint impairment. Osteoarthritic chondrocytes show an altered phenotype characterised by an excess production of catabolic factors, including metalloproteinases and reactive oxygen species. These factors constitute potential therapeutic targets and some new drugs and nutraceuticals have been proposed to promote the return to homeostasis. Until now, the therapeutic management of OA in dogs has been dominated by nonsteroidal anti-inflammatory drugs, but some new compounds, including diacerhein, with potential structure-modifying effects, are already used to treat OA in humans and could be helpful to manage OA in the dog. In addition, novel nutraceuticals, such as avocado/soybean unsaponifiable substances, have shown symptomatic effects in knee OA in humans, and could offer an alternative to prevent OA progression. This paper provides an overview of recent discoveries in the pathophysiology and in the therapeutic management of osteoarthritis in dogs. 相似文献
107.
OBJECTIVE: Evaluation of the LMA-ProSeal for positive pressure ventilation (PPV) in the pig. STUDY DESIGN: Prospective observational study. ANIMALS: Twelve German country pigs, weighing 25-62 kg. METHOD: Lungs of pigs were mechanically ventilated under general anaesthesia using the LMA-ProSeal. The ease of insertion, number of attempts and total time until placement of the LMA-ProSeal and gastric tube were recorded. Bronchoscopy was performed to determine the position of the LMA-ProSeal and to detect signs of aspiration. Ventilation variables and the leak airway pressure (P(leak)) were measured. An arterial blood gas sample was taken to determine the adequacy of ventilation. RESULTS: The airway was secured in all pigs within 39 +/- 19 seconds (27-51). Different sizes of LMA-ProSeal were used; up to 30 kg: size 3, up to 43 kg: size 4; and above 43 kg: size 5. In all but one animal the P-LMA and gastric tube were inserted at the first attempt. In nine animals gastric fluid was drained through the gastric tube. There was no evidence of aspiration in any animal. The mean [+/-SD (95%CI)]P(leak) was 28.8 +/- 7.5 cm H(2)O (24.06-33.60) and normal ventilation was achieved in all animals. CONCLUSIONS: The results of this study indicate that the airway of pigs weighing 25-62 kg can be secured safely and reliably with the sizes 3, 4 and 5 LMA-ProSeal. CLINICAL RELEVANCE: Endotracheal intubation in pigs can be difficult so there is a risk of hypoxemia in the apnoeic animal. With the LMA-ProSeal the airway can be secured rapidly, safely and reliably. Use of the Standard-LMA under PPV can be associated with gas leakage into the stomach and the subsequent risk of gastric distension and regurgitation. Both the ability to drain the stomach and the high P(leak) of the LMA-ProSeal could contribute to improved protection against aspiration under PPV. 相似文献
108.
It is reasonable to assume that there is a relationship between the spatial distribution of forest fuels and fire hazards.
Therefore, if fire risk is to be included into numerical forest planning, the spatial distribution of risky and non-risky
forest stands should be taken into account. The present study combines a stand-level fire risk model and landscape level optimization
to solve forest planning problems in which the fire risk plays an important role. The key point of the method was to calculate
forest level fire resistance metrics from stand level indices and use these metrics as objective variables in numerical optimization.
This study shows that maximizing different landscape metrics produces very different landscape configurations with respect
to the spatial arrangement of resistant and risky stands. The landscapes obtained by maximizing different metrics were tested
with a fire spread simulator. These tests suggested that the mean fire resistance of the landscape, which is a non-spatial
metric, is the most important factor affecting the burned area. However, spatial landscape metrics that decrease the continuity
of fire resistance in the landscape can significantly improve the fire resistance of the landscape when used as additional
objective variables. 相似文献
109.
ABSTRACT Change in relative frequencies of the three main genetic types of Botrytis cinerea (Group I, Group II vacuma, and Group II transposa) were monitored over time from 1998 to 2000 in three Bordeaux vineyards not treated with fungicides. During 2000, Group I isolates, detected mostly at flowering comprised only 2.5% of the entire population. Within Group II, the complementary frequencies of vacuma and transposa isolates differed significantly depending on grapevine phenological stages and organs. Every year and at all sites, including one noble rot site, transposa isolates dominated at every stage, particularly on overwintering canes and at harvest (greater than 86.7% on berries). The complementary frequency of vacuma isolates reached a maximum on senescing floral caps (between 23.5 and 71.4%) and then decreased significantly until harvest on leaves and berries. In pathogenicity tests on grape berries, transposa isolates were significantly more virulent than were vacuma isolates. Mycelial growth rate was negatively correlated with virulence, notably on leaves in transposa and with double resistance to the fungicides carbendazim and vinclozolin. In vacuma, this double resistance was positively correlated with virulence on leaves. Change in the vacuma and transposa frequencies was most likely caused by differences in saprotrophic and pathogenic fitness. Possible interactions between fungicide resistance profiles and fitness are discussed. 相似文献
110.
ABSTRACT The Fusarium spp. causing Fusarium crown and root rot (FCRR) are ubiquitous and abundant in soils, but in contrast, disease expression is localized and sporadic. Previous studies have related FCRR infection to phenolic acids released by asparagus, to the repression of Mn-reducers in soil, and to various soil physicochemical conditions. Fifty commercial asparagus plantations were surveyed using an exploratory approach in order to pinpoint the ecological conditions associated with FCRR development. Twenty-eight variables were used to describe the soil environments of the asparagus crops as well as the influence of crop management practices used locally. The data set was analyzed both as a whole and parsed by main cultivars (Jersey Giant and Guelph Millenium). Both field conditions and percentage of field area affected by FCRR varied widely between asparagus plantations. Planting depth was positively correlated with percentage of field area affected by FCRR and, hence, deep planting may favor FCRR infection. Plantation age was positively correlated with percentage of field area affected by FCRR, while soil available Mn was inversely correlated. Most importantly, soil Mn availability decreased with increasing plantation age, supporting the hypothesis of an asparagusmediated negative impact on Mn-reducing bacteria and of the involvement of reduced Mn availability in FCRR development. Improving the availability of Mn could provide a solution to the problem of FCRR in asparagus plantations. 相似文献