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351.
Extract

During the period from April 1, 1964 to February 28, 1966, veterinary surgeons of the Huntly District Veterinary Club conducted an investigation into the incidence, the cause, subsequent fertility and treatment of dairy cows with retained foetal membranes.  相似文献   
352.
Extract

The aims of this survey were to decide the annual incidence, the causes, and the economic importance of abortions occurring in a random sample of dairy herds in the Huntly district.  相似文献   
353.
This study assessed the standard urinalysis technique and sediment stain techniques as predictors of bacterial culture results for canine and feline urine. Canine (n = 111) and feline (n = 79) urine samples were evaluated using unstained wet-mount and air-dried Gram and Wright-Giemsa stained sediment; results were compared to aerobic bacterial culture. Eleven canine and 7 feline urine samples were culture positive. Unstained wet-mount and stained sediment had sensitivities of 89% and 83% and specificities of 91% and 99%, respectively. The specificity of using either stain was higher (P < 0.01) than wet-mount examination for detecting bacteriuria. There were significant differences among 3 technologists in detecting true positives (P < 0.01). Association of sediment and culture results used 112 canine and 81 feline samples. There was a negative association (P < 0.01) between lipid detection and wet-mount identification of bacteria.  相似文献   
354.
Extract

This work was carried out during the springs of 1968 and 1969. The aims were to study involution and early ovarian activity in general, and, in particular, to compare these phenomena in two groups of cows subjected to different management. One group comprised cows milked twice daily, the other, cows which suckled three or four calves each.  相似文献   
355.

Background

Sepsis caused by Staphylococcus aureus often leads to brain microabscesses in humans. Animal models of haematogenous brain abscesses would be useful to study this condition in detail. Recently, we developed a model of S. aureus sepsis in pigs and here we report that brain microabscesses develop in pigs with such induced S. aureus sepsis.Twelve pigs were divided into three groups. Nine pigs received an intravenous inoculation of S. aureus once at time 0 h (group 1) or twice at time 0 h and 12 h (groups 2 and 3). In each group the fourth pig served as control. The pigs were euthanized at time 12 h (Group 1), 24 h (Group 2) and 48 h (Group 3) after the first inoculation. The brains were collected and examined histopathologically.

Results

All inoculated pigs developed sepsis and seven out of nine pigs developed brain microabscesses. The microabscesses contained S. aureus and were located in the prosencephalon and mesencephalon. Chorioditis and meningitis occurred from 12 h after inoculation.

Conclusions

Pigs with experimental S. aureus sepsis often develop brain microabscesses. The porcine brain pathology mirrors the findings in human sepsis patients. We therefore suggest the pig as a useful animal model of the development of brain microabscesses caused by S. aureus sepsis.  相似文献   
356.
Samples of pine (Pinus sylvestris) and spruce (Picea abies) were impregnated with a low-viscous epoxy resin using a vacuum process. The epoxy was cured in situ and the specimens sectioned. Deposits of the cured epoxy was then observed in the wood cavities using a scanning electron microscope. The investigation concentrated on tracing the transverse movements of a viscous liquid in the wood, and special attention was therefore given to the cross-field area between ray cells and longitudinal tracheids. A damage hypothesis is proposed based on the results obtained in the present investigation in combination with those from earlier studies on linseed oil-impregnated pine: In addition to the morphology of the bordered pits, viscous liquid flow in wood is dependent on damage that occurs during the impregnation procedure. For pine sapwood, liquid flow is enabled through disrupted window pit membranes, which divide the longitudinal tracheids and the ray parenchyma cells. A mechanism accounting for the reduced permeability of pine heartwood is believed to be deposits of higher-molecular-weight substances (extractives) in the ray parenchyma cells and on the cell walls. In spruce the thicker ray cells in combination with the smaller pits, which are connected to the longitudinal tracheids, reduce permeability considerably.  相似文献   
357.
Aphandra natalia (Balslev & Henderson) Barfod is native to the western Amazon. It is exploited commercially for its leaf sheath and petiole fibers, which are used for brooms. Data from a 2 year study on production and harvest of fibers in the province of Morona-Santiago in Ecuador shows correlations to exist between the degree of the palm's exposure to light and leaf production, and between exposure to light and petiole length (maximum fiber length), while correlation is absent between exposure to light and fiber load per leaf. A linear relation was found between time and leaf production, with an overall average of 5.5 leaves produced per palm per year. No difference in leaf production of male and female palms was found among palms growing at low light intensities, while among palms in open, light-exposed areas, males were found to produce significantly more leaves than females. An average of 8.5 leaves are cut per palm per harvest, yielding 3.4 kg of fibers, while 6.9 leaves are left untouched. Average harvest time per palm is 33 min. Under optimal conditions (high densities of easy accessible palms), one harvester may harvest and clean about 20 kg of fibers in 1 day, selling at US$1.1 kg−1. One hectare with high, but natural, densities of the palm may produce fibers worth US$460 per year, which can be harvested and prepared in 22 work days. Exploitation of the edible fruits may be combined with fiber extraction if female palms are left to produce fruits, while male palms are exploited for fibers, or if harvest frequency of fibers from female palms is lowered considerably below the average of once every 1.55 years. The exploitation practised in the study area appears sustainable.  相似文献   
358.
Total arsenic is determined by inductively coupled plasma atomic emission using hydride vapor generation. A 1 g sample is wet washed in a 16 x 150 mm 10 mL volumetric test tube on a programmed heating block with nitric, sulfuric, and perchloric acids at up to 310 degrees C. After treatment with hydrochloric acid and potassium iodide, arsenic is reduced by sodium borohydride to arsine in a simplified continuous flow manifold. A standard pneumatic nebulizer affects the gas-liquid separation of AsH3, which is quantified by ICP atomic emission at 193.756 nm. The instrument detection limit for the method has been determined to be 0.4 microgram/L. For a 10:1 dilution of a nominal 1 g sample, the detection limit is 4 micrograms/kg and the linear range is up to 4 mg/kg. Recoveries from 3 matrixes were 99-104%, with a typical RSD of 2%. The method has demonstrated statistical control for samples of biological interest and is especially well suited to analysis of small samples.  相似文献   
359.
Deoxyhemoglobin-mediated lipid oxidation in washed fish muscle   总被引:1,自引:0,他引:1  
Deoxyhemoglobin-mediated lipid oxidation was studied by comparing the pro-oxidative activity of anodic and cathodic hemoglobins from trout in a washed cod muscle model system. At pH 6.3, cathodic hemoglobins were nearly fully oxygenated while anodic hemoglobins were poorly oxygenated. Anodic hemoglobins initiated lipid oxidation in washed cod muscle much more rapidly than cathodic hemoglobins, as measured by thiobarbituric acid reactive substances (TBARS) formation. Moreover, anodic hemoglobins appeared to oxidize more rapidly as compared to cathodic hemoglobins in the washed cod muscle model system, as measured by a decrease in redness (a value). A more pronounced pro-oxidative activity of deoxyhemoglobin as compared to oxyhemoglobin was confirmed by accelerated lipid hydroperoxide and TBARS formation in the washed cod muscle model system upon combined addition of anodic hemoglobins and adenosine triphosphate, which is known to lower the oxygenation of anodic hemoglobins at pH 7.2, as compared to only addition of anodic hemoglobins to the washed cod muscle. These studies suggest that deoxyhemoglobin is more pro-oxidative than its oxygenated counterpart at pH values found in postmortem fish muscle.  相似文献   
360.
We studied the effects of habitat fragmentation, measured as forest stand size and isolation, on the distribution of Eurasian red squirrels (Sciurus vulgaris). Squirrel density was surveyed during four years in 46 forest stands (0.1–500 ha) in a forest landscape in south-central Sweden. The only factor that significantly influenced a density index was the proportion of spruce within a habitat fragment. Neither fragment size nor degree of isolation were significant. Furthermore, none of the interactions with year were significant, suggesting the same pattern in all four years. Thus, the effect of habitat fragmentation in this study seems to be only pure habitat loss, i.e. halving the proportion of preferred habitat in the landscape should result in a halving of the red squirrel population. Therefore, the landscape can be viewed as functionally continuous for the squirrels, although the preferred habitat was divided into fragments. The most likely explanation for the difference between this study and other studies on squirrels that found effects due to habitat fragmentation is a combination of shorter distances and less hostile surroundings in our study area. To identify landscape effects requires multiple studies because single studies usually consider only one landscape.  相似文献   
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