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51.
 A test method was developed to calculate the amount of fluid needed to achieve full penetration in Pinus sylvestris sapwood samples. The samples were treated using a vacuum schedule with a range of solvents with varying swelling capabilities. The solvents were xylene, methanol, water and three intermediate binary solutions. It was found that there was a linear relationship between full penetration uptake and swelling. The swelling and uptake were related to the interaction between the solvents and the wood cell wall. An extensive literature review is contained within this paper based on the interaction between fluids and the wood cell wall to assist with the interpretation of results produced by the experiment. Received 22 November 1999  相似文献   
52.
53.
This study evaluated the performance of an immunochromatographic test (ICT) for the diagnosis of canine brucellosis caused by Brucella canis, comparing its results with that of the rapid slide agglutination test with and without the use of 2‐mercaptoethanol and the agar gel immunodiffusion test (AGID). The microbiological culture, PCR and clinical examination were used as reference. According to the results obtained in clinical examination, blood culture, culture of semen and vaginal swab and PCR in blood, semen and vaginal swab, a total of 102 dogs were divided into three groups: B. canis‐infected dogs (Group 1), B. canis‐non‐infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The diagnostic sensitivity of RSAT, 2ME‐RSAT, AGID and ICT in Group 1 was, respectively, 75%, 37.5%, 27.8% and 89.58%. The diagnostic specificity of RSAT, 2ME‐RSAT, AGID and ICT in Group 2 was, respectively, 91%, 100%, 100%, and 100%. In dogs with suspected brucellosis, 9.67% were RSAT positive, none was positive by 2ME‐RSAT, 3.22% were AGID positive and 6.45% were ICT positive. The main drawback concerning canine brucellosis diagnosis is the lack of a highly sensitive serological assay to be used as a screening test to the rapid identification of infected animals. The ICT showed a high diagnostic specificity and a diagnostic sensitivity value greater than that observed in the RSAT, 2ME‐RSAT and AGID. However, 10.41% of infected dogs had negative results by ICT. These dogs were positive by microbiological culture and/or PCR, indicating active infection and consequently a higher potential of spreading Brucella. Although rapid and simple to perform, the ICT lacked sensitivity to be used as a screening test.  相似文献   
54.
The deuterium-hydrogen abundance ratio in the Venus atmosphere was measured while the inlets to the Pioneer Venus large probe mass spectrometer were coated with sulfuric acid from Venus' clouds. The ratio is (1.6 +/- 0.2) x 10(-2). The hundredfold enrichment of deuterium means that at least 0.3 percent of a terrestrial ocean was outgassed on Venus, but is consistent with a much greater production.  相似文献   
55.
Simultaneous miocene extension and shortening in the himalayan orogen   总被引:5,自引:0,他引:5  
The South Tibetan detachment system separates the high-grade metamorphic core of the Himalayan orogen from its weakly metamorphosed suprastructure. It is thought to have developed in response to differences in gravitational potential energy produced by crustal thickening across the mountain front. Geochronologic data from the Rongbuk Valley, north of Qomolangma (Mount Everest) in southern Tibet, demonstrate that at least one segment of the detachment system was active between 19 and 22 million years ago, an interval characterized by large-scale crustal thickening at lower structural levels. These data suggest that decoupling between an extending upper crust and a converging lower crust was an important aspect of Himalayan tectonics in Miocene time.  相似文献   
56.
The kangmar dome: a metamorphic core complex in southern xizang (tibet)   总被引:5,自引:0,他引:5  
The Kangmar metamorphic-igneous complex is one of the most accessible examples of an enigmatic group of gneiss domes (the North Himalayan belt) that lies midway between the Greater Himalaya and the Indus-Tsangpo suture in southern Tibet. Structural analysis suggests that the domal structure formed as a consequence of extensional deformation, much like the Tertiary metamorphic core complexes in the North American Cordillera. Unlike its North American counterparts, the Kangmar dome developed in an entirely convergent tectonic setting. The documentation of metamorphic core complexes in the Himalayan orogen supports the emerging concept that extensional processes may play an important role in the evolution of compressional mountain belts.  相似文献   
57.
Fourteen of 24 pigs were immunised with repeated injections of killed cultures of Leptospira serotype pomona administered over a three-week period. The remaining 10 pigs served as controls.

Five days after immunisation all pigs were exposed to the same natural infection by being housed together for 12 weeks in a pen which received effluent from other pens containing infected pigs.

Neither leptospiruria nor kidney lesions were detected in any of the immunised pigs. In contrast, leptospiruria and kidney lesions occurred in all the controls.

The development of serum agglutinins after immunisation and before exposure suggested that this could be used as an index of adequate antigenic stimulation.  相似文献   
58.
Nineteen isolates of Actinobacilfus suis were recovered from horses during the period October 197%December 1980. Animals varied in age from a full term foetus to 12 years. One isolate was obtained from the nose of an apparently healthy horse, the remainder were obtained from still-born foetuses (2), foals dying within a week of birth (5), older animals with respiratory (6) or genital infections (3) or abscesses in the jaw (1). One isolate was obtained from the lung of a 2-week-old foal which had shown diarrhoea.

The bacteriological characteristics of the isolates and the pathological lesions present in eight cases are described. The organism has a wide geographical distribution in New Zealand, and in the northern part of the North Island appears to be more common than A. equuli.  相似文献   
59.
Mastitis caused by the colourless alga Prototheca zopfii was diagnosed in 17 of 120 cows in a dairy herd. Infection occurred in animals varying from 3–14 years old and was present in one to four quarters of each cow.

Nine cases were associated with clinical mastitis characterised by the presence in milk of flakes or small clots. Somatic cell counts consistent with subclinical mastitis (>500 × 103 cells/ml) were recorded in five of the eight remaining cows.

Histological examination of udder tissue showed the presence of granulomatous lesions associated with the presence of Prototheca.

The problem was identified and controlled by repeated microbiological examination of milk samples from all lactating cows and immediate culling of infected animals.

P. zopfii was also recovered from environmental water samples on this farm. It is suggested that infection may have occurred as a result of teat sores caused by trauma from a milking machine, and the tendency for cows to lay down on a race, the surface of which was sometimes flooded by drain water in which Prototheca were present.  相似文献   
60.
Itraconazole for the Treatment of Histoplasmosis in Cats   总被引:2,自引:0,他引:2  
Eight cats with histoplasmosis were treated with itraconazole at 5 mg/kg per dose PO bid. There were multiple sites of infection, and 2 of the cats had hypercalcemia that was attributed to the histoplasmosis. All 8 cats were eventually cured, but 2 cats experienced recurrences of disease after completion of therapy, requiring 2 to 3 additional months of itraconazole. There were no clinically relevant adverse effects during treatment. Although a limited number of cats were treated, the study suggests that itraconazole is a well-tolerated and effective drug for the treatment of histoplasmosis in the cat.  相似文献   
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