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61.
The relationships between bispectral index (BIS), cardiovascular variables and minimum alveolar concentration (MAC) multiples of sevoflurane in puppies were determined. Five puppies were anesthetized with sevoflurane on two occasions. First, the individual sevoflurane MAC values were determined for each puppy. Secondly, dogs were anesthetized with sevoflurane at each of 5 MAC multiples, 0.75, 1, 1.25, 1.5 and 1.75 MAC administered in random order. Hemodynamic parameters and BIS data were collected for 20 min. Somatic stimulus was then applied and the same parameters and data were collected for 6 min. Correlation between BIS and end tidal sevoflurane and between BIS and hemodynamic parameters were studied. We found positive significant correlation in both cases. BIS is lower in puppies that in adults at the same alveolar anesthetic concentrations and sevoflurane appears to be a safe anesthetic in puppies.  相似文献   
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Albumin-based rigid and elastic foams were prepared by mechanically beating water solutions of the protein mixed with formaldehyde and camphor. The resulting foams were cross-linked in a traditional or in a microwave oven. Formaldehyde was used as hardener of the protein and camphor as a plasticizer. Thermal conductivity was tested and found to be acceptable for thermal insulation but did not appear to be influenced by variations in foam density. Scanning electron microscopy of the different formulations showed some differences in cells structure. Formulations of different water content, formaldehyde hardener content, camphor content and oven curing time were tested. Within certain limits (a) increases in water proportion rendered the foam more elastic, (b) higher formaldehyde content increased foam rigidity and strength up to a value beyond which no further increase occurred, (c) the amount of camphor influences markedly the compression strength and foam elasticity/plasticity, (d) curing time improving foam strength up to 5 min in microwave curing, without any further effect for longer heating times. Only addition of glycerol, yielded truly soft elastic foams.  相似文献   
64.
The point of no return (PNR) and disappearance of the oil droplet were measured in Chirostoma estor larvae as a function of the time of first feeding. In a separate trial, growth and survival of larvae fed rotifers enriched with Chlorella sp., cod liver oil and corn oil were assessed. Fatty acid and lipid composition of eggs, oil droplets, egg yolk, feed and larvae were also evaluated. The PNR was found between 7 and 8 days posthatching (dph). Total oil droplet depletion occurred between 7 and 11 dph, depending on the time of first feeding. Best growth and survival were obtained in larvae fed with Chlorella‐enriched rotifers, followed by those fed cod liver oil‐enriched rotifers. In larvae fed corn oil, Chlorella and cod liver oil‐enriched rotifers, total oil droplet depletion took place on days 9, 10 and 11, respectively. There was a direct relationship between presence and duration of oil droplets and the survival of larvae under different starvation conditions. The feed source could prolong the existence of the oil droplet depending on particular dietary supply of essential fatty acids; the time of its disappearance could be a useful indicator of larval vigour and health status.  相似文献   
65.
Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.  相似文献   
66.
A study was made of serum concentrations of cholesterol, phospholipids, triglycerides, cholesterol bound to high-density lipoproteins (HDL), HDL1-cholesterol, HDL2-cholesterol and cholesterol bound to low-density lipoproteins (LDL) in 16 dogs naturally infected with Leishmania infantum (ZMON-1) taken from an endemic focus. Results were compared with those of a control group of ten healthy dogs. Statistically significant increases in cholesterol, triglyceride and LDL-cholesterol levels were observed. There was, however, a statistically significant decrease in HDL-cholesterol level, mainly at the expense of the HDL2-cholesterol subfraction. Cholesterol transport is therefore shown to undergo changes which may be attributed to the consumptive evolution of the disease, immunocomplex deposits in cells, hepatic disorders and interactions between the parasite and the normal cholesterol metabolism of the host.  相似文献   
67.
Beak and feather disease (psittacine circovirus) and Budgerigar fledgling disease (avian polyomavirus) are viral diseases that can frequently affect captive psittacine birds. We designed the first survey to investigate the presence of beak and feather disease virus (BFDV) and Avian polyomavirus (APV) inside the population of captive psittacine birds in Italy. Samples were collected in 18 Italian psittacine breeding centres and four trade centres over a 4-year period. A total of 1516 birds were tested for BFDV and 877 birds were tested for APV by means of a polymerase-chain-reaction (PCR) assay. BFDV was found in 122 (8.05%) and APV in 7 (0.79%) birds. No significant difference in infection rate was found between imported and locally raised parrots. We report the first BFDV DNA isolation in wild birds imported to Italy from Papua New Guinea.  相似文献   
68.
Ten gram-negative, pleomorphic, rod-shaped isolates from coryza-like, respiratory diseased laying and broiler chickens were identified as Ornithobacterium rhinotracheale. All O. rhinotracheale isolates showed typical biochemical and enzymatic characteristics. Also, all isolates showed hemagglutinating activity with glutaraldehyde-fixed erythrocytes. On the basis of this property, a rabbit-raised antiserum was produced for an isolate. All isolates were identified by antiserum by hemagglutination-inhibition tests. No cross-reactions were observed when O. rhinotracheale isolates were tested with Haemophilus paragallinarum antisera, and vice versa. Mild respiratory signs, including mild nasal discharge, slight rales, and sneezing, were observed in challenged chickens. At postmortem examination, multifocal pneumonia, airsacculitis, and foamy exudate in abdominal cavity were observed. Furthermore, because bacterial adherence is regarded as an essential step in the infection process, in vitro adherence of O. rhinotracheale isolates to chicken tracheal epithelial cells was tested. All isolates showed positive adherence. Obtained results indicate that O. rhinotracheale is a pathogenic agent present in the Mexican poultry.  相似文献   
69.
Babesia ovis isolated in Extremadura (Spain) was the subject of a serological study in experimentally inoculated sheep. The first antibody titres, determined by the indirect fluorescent antibody (IFA) test, were observed 7-8 days post infection (p.i.) in all animals except the splenectomized group, in which the only animal that survived showed antibody response 10 days p.i. A faster response following challenge was observed in sheep which were seropositive before inoculation, which suggests the existence of an antigen memory. The highest titres were reached 16-25 days p.i., and subsequently began to fall, reaching minima at the end of the experimental period (330 days p.i.). The chronic carrier state in experimental B. ovis infection had a duration of at least 2 years. Passive transmission of antibodies from experimentally infected mothers to newborn lambs was also detected. Antibody levels were observed for a period not longer than 2 months after birth.  相似文献   
70.
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