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91.
Fine needle aspiration biopsy is a fast and inexpensive technique well tolerated by animals. Its efficacy for the diagnosis of malignancy and determination of cellular origin was investigated for 97 malignant tumors and five benign lesions in 83 dogs and 19 cats. Histological examination of the lesions was performed in each case. Malignancy was detected by cytology in 69% of the malignant tumors. The cellular origin of the lesion was determined in 74% of the cases. Confirmation of malignancy and determination of cellular origin permitted an early diagnosis and prognosis. Since fine needle aspiration biopsy and cytology cannot definitely rule out malignancy, a surgical biopsy and histopathology should be done when malignancy is suspected clinically and not confirmed cytologically. Specimens of good quality, adequate collaboration between the cytologist and clinicians, and sufficient knowledge of pathology and cytology are basic requirements for obtaining good results with fine needle aspiration biopsy and cytology.  相似文献   
92.
Wilson EO 《Science (New York, N.Y.)》1985,228(4707):1489-1495
Studies on the social insects (ants, bees, wasps, and termites) have focused increasingly on sociogenesis, the process by which colony members undergo changes in caste, behavior, and physical location incident to colonial development. Caste is determined in individuals largely by environmental cues that trigger a sequence of progressive physiological restrictions. Individual determination, which is socially mediated, yields an age-size frequency distribution of the worker population that enhances survival and reproduction of the colony as a whole, typically at the expense of individuals. This "adaptive demography" varies in a predictable manner according to the species and size of the colony. The demography is richly augmented by behavioral pacemaking on the part of certain castes and programmed changes in the physical position of colony members according to age and size. Much of what has been observed in these three colony-level traits (adaptive demography, pacemaking, and positional effects) can be interpreted as the product of ritualization of dominance and other forms of selfish behavior that is still found in the more primitive insect societies. Some of the processes can also be usefully compared with morphogenesis at the levels of cells and tissues.  相似文献   
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A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.

Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.

  相似文献   
96.
1. On average, over the laying year, a higher proportion of eggs were cracked from cages (4.6%) than from range (2.0%); the difference tended to increase as the flocks aged.

2. There was evidence that eggs from range had stronger shells: they required more energy to crack, shell thickness was greater and shell deformation at 70 weeks was less (though the difference was not significant).

3. The differences between systems in shell strength, although real, were small. It is probable that environmental insults make a much larger contribution than shell strength to differences in crack incidence.

4. Eggs laid by hens on range were larger (+ 6.8% at 36 weeks and + 2.9% at 70 weeks) than those laid by the same stock housed in cages.  相似文献   

97.
1. Methods for quantitative determination of proteolytic, lipolytic and haemolytic activities and egg yolk factors in semen are described.2. Comparative quantitative determinations of these enzyme activities in the semen of goat, ram, bull, boar, dog and horse have been carried out.3. Special interest attaches to the egg yolk turbidity factor which is found in goat semen and, in small concentrations, also in boar semen.4. As each species appears to have its specific enzyme pattern, regular enzymatic control does not seem to have great significance.  相似文献   
98.
1. Two experiments were conducted to evaluate the effects of including ascorbic acid (AA), palm oil or a combination of both in the diets of laying hens during the hot months in a tropical environment.

2. The inclusion of AA improved egg production, food intake and efficiency of utilisation, and decreased the cost of food per kg egg. The addition of 400 mg AA/kg diet gave the most efficient performance.

3. Palm oil inclusion reduced the effect of heat stress and increased egg production, egg weight, food intake and efficiency of utilisation.

4. When 200 mg AA and 50 g palm oil/kg were used, additive responses were obtained with further improvements in egg production, food cost and efficiency.

5. Ascorbic acid and palm oil when fed alone or in combination reduced the incidence of cracked eggs.

6. Thus, 400 mg ascorbic acid/kg of diet, 50 g palm oil or 200 mg AA plus 50 g palm oil/kg diet ameliorated the effects of heat stress in laying hens.  相似文献   

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Glasser's disease accounted for less than 1% of total swine mortalities in an 11 year retrospective postmortem survey of swine submissions at three provincial government diagnostic laboratories in southern Ontario. However, Glasser's disease was suspected in 17 of 83 boar mortalities at the Record of Production Boar Test Station between 1983 and 1985 and was much more common in specific-pathogen-free (SPF) boars than in conventional boars. The prevalence of the causative organism, Haemophilus parasuis, was determined for 19 SPF herds in Ontario classified as "Excellent" under the Ontario Swine Herd Health Policy. Nasal swabs from two-month-old pigs were cultured on chocolate agar containing 1.5 mug/mL lincomycin, 5 mug/mL bacitracin, and 0.1 mug/mL crystal violet. Three herds were negative for H. parasuis infection; 16 herds contained clinically healthy carrier pigs.  相似文献   
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