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101.
Chir pine (Pinus roxburghii) is an important tree species that grows all along the Himalayas. Wood specific gravity of chir pine before and after removal of extractives from wood increment cores was assessed from a 22-years-old progeny test in Himachal Pradesh, India. These values averaged 0.433 and 0.425, respectively. A large amount of genetic variation among the 58 half-sib families was found as indicated by range of values, additive coefficient of variation, variance estimates and narrow-sense heritability values for these traits. Moisture and extractive content averaged 86.259% of oven-dry weight and 2.003% of extractive-free oven-dry weight, respectively. Wood extractive content was highly variable and the family differences were highly heritable (h f2 = 0.5831). There was wide variability in moisture content, but a large portion of it was due to environmental or non-additive component of genetic variation. Heritability on family mean basis was found to be lower than that on individual tree basis for each trait. Estimated gain in specific gravity resulting from 30 to 50% family selection ranged from 0.0080 to 0.0127. Growth data and specific gravity were not significantly correlated implying that selection for higher growth rate would not necessarily result in reduction in wood specific gravity in chir pine.  相似文献   
102.
SUMMARY A study of the prevalence, spread and control of caprine arthritis-encephalitis virus (CAEV) in dairy goat herds in New South Wales (NSW) during 1986–1988 found that 56.8% of 1484 goats in 14 dairy herds were infected with CAEV. The prevalence of CAEV infection within most herds not implementing control measures increased during the study. At the end of the study, 59.7% of 1322 goats were infected. The prevalence of CAEV increased with age. Differences between breeds were less apparent. Within seven herds with a high standard of identification of goats, 149 of 812 goats seroconverted in an ELISA. Of these newly infected goats, 142 (95.3%) were > 1 yr of age and 96 (64.4%) were > 2 yr suggesting lateral spread of the virus. Most of the goats > 2 yr of age had been in the milking herd for a minimum of 3 to 6 months. The high seroconversion rate within the milking herd suggested that factors other than the ingestion of infected colostrum and milk before weaning were important for the spread of CAEV. Observations indicated that behaviour of goats, particularly reproductive behaviour among lactating does, and milking herd management practices are important in the spread of CAEV. A high density of livestock, poor livestock control and contamination of feed, water, equipment and personnel were implicated in transmission. Poorly functioning milking machines may also be involved. CAEV was eradicated from 3 herds by the implementation of strict control measures.  相似文献   
103.
Objective — Assessment of a microsurgical technique for transsphenoidal hypophysectomy in dogs.
Study Design — Prospective study using physical examination, pituitary function testing, computed tomography (CT), and histological examination at autopsy.
Animals or Sample Population — Eight laboratory beagle dogs.
Methods — Pituitary function was assessed before and at 10 weeks after hypophysectomy by combined administration of four releasing hormones (anterior pituitary), administration of haloperidol (pars intermedia), and infusion of hypertonic saline (posterior pituitary).
Results — CT imaging enabled accurate preoperative localization of the pituitary. Appropriate positioning and surgical technique facilitated exposure of the pituitary and its extraction without hemorrhage. Postoperative recovery was generally uncomplicated. None of die eight dogs had somatotropic, gonadotropic, lactotropic, melanotropic, or posterior pituitary responses to stimulation at 10 weeks after hypophysectomy. Four dogs (ACTH nonresponders) also had no cortico-tropic response and four (ACTH responders) had small but significant responses in the combined anterior pituitary function test. Adrenocortical atrophy was more pronounced in the ACTH nonresponders man in the responders. No residual pituitary tissue was found along the ventral hypothalamic diencephalon but nests of pituitary cells were found embedded in fibrous tissue in the sella turcica.
Conclusions — The surgical technique proved to be safe and effective. Microscopic nests of pituitary cells in the sella turcica may be responsible for residual corticotropic response to hypophysiotropic stimulation after hypophysectomy.
Clinical Relevance — The surgical technique may be used in the treatment of dogs with pituitary-dependent hyperadrenocorticism. The corticotropic response is the most sensitive criterion in assessing completeness of hypophysectomy in dogs.  相似文献   
104.
In two experiments, we examined the effect of administration of cloprostenol at artificial insemination on fertility of multiparous sows. Lactation length was 21 days and only sows exhibiting estrus by 7 days after weaning were included. Cloprostenol was administered by IM injection (175 microg; n=126) or supplemented in the semen dose (525 microg; n=129). Control sows (n=130) received no hormone. In either experiment, there was no effect of any treatment on subsequent litter sizes. In experiment 1, there was no effect of treatment on farrowing rate, but in experiment 2, farrowing rate was higher (p < 0.05) in sows receiving cloprostenol by injection. Taken together, these results indicate no consistent effect of cloprostenol administration by intramuscular injection or by inclusion in the semen dose on sow fertility and so its routine use is not warranted.  相似文献   
105.
Dynamic helical computed tomography (CT) of the pituitary gland can be used to image the three-dimensional shape and dimensions of abnormalities within the pituitary gland. The aim of this study was to develop a protocol for dynamic helical CT of the pituitary gland in healthy dogs as a future reference study for patients with pituitary disease. Dynamic helical series of nine scans of the pituitary gland during and following contrast medium injection were performed in six healthy dogs using the following protocols: a series with 1 mm collimation and a table feed per X-ray tube rotation of 2 mm (pitch of 2) in six dogs, a series with 2 mm collimation and pitch of 2 in three dogs, and a series with 1 mm collimation and pitch of 1 in three other dogs. Multiplanar reconstructions of the images were made using a reconstruction index of 0.5. Images of all series were assessed visually for enhancement of the arteries, the neurohypophysis, and the adenohypophysis. The enhancement pattern of the neurohypophysis was distinguished adequately from that of the adenohypophysis in five dogs that were scanned with 1 mm collimation and pitch of 2, but the difference was less discernable when the other protocols were used. The carotid artery, its trifurcation, and the arterial cerebral circle were best visualized in dorsal reconstructions. Dynamic helical CT of the pituitary gland in healthy dogs can be performed with 1 mm collimation and pitch of 2, and a scan length that includes the entire pituitary region. Using this protocol, with the specific scanner used, the neurohypophysis, the adenohypophysis, and the surrounding vascular structures are adequately visualized.  相似文献   
106.
Human T-lymphotropic virus type III (HTLV-III) is thought to play an etiologic role in the development of the acquired immune deficiency syndrome (AIDS). In this study the serologic characterization of a new simian retrovirus that is related to HTLV-III is described. This new virus, here referred to as STLV-III, was isolated from sick macaques at the New England Regional Primate Research Center. Radioimmunoprecipitation analysis revealed STLV-III-specific proteins of 160, 120, 55, and 24 kilodaltons, all similar in size to the major gag and env proteins of HTLV-III. These antigens were recognized by representative macaque serum samples and human reference serum samples positive for HTLV-III antibodies. Monoclonal antibodies directed to p24, the major core protein of HTLV-III, also immunoprecipitated a 24-kilodalton species in lysates of cells infected with the macaque virus. This HTLV-III-related virus, which naturally infects a nonhuman primate species, may provide a useful model for the study of HTLV-III and the pathogenesis of AIDS.  相似文献   
107.
Five varieties of Amaranthus cruentus were planted in 3 localities at different altitudes above sea level. They were subjected to equivalent agronomic practices and harvested at 120–130 days. The seeds were removed and dried to 12% moisture. The seeds from each variety were analyzed for total fat, palmitic, stearic, oleic and linolenic acids and squalene contents. Oil content varied from 5.83 to 7.13%, palmitic acid from 17.06 to 21.35%, stearic acid from 3.05 to 3.80%, oleic acid from 20.26 to 32.01% and linoleic acid from 33.52 to 43.88%. The values for oil and fatty acid contents were similar to those found in the literature. The differences in the analytical values of the present study were not statistically significant for variety or for location.Squalene content varied from 2.26 to 5.94% of the oil. This variability is similar to that reported previously by other workers. Statistical analysis showed significant difference for localities but not for varieties. It is suggested that environmental conditions, such as temperature and water availability, may lead to a greater accumulation of squalene in the grain.  相似文献   
108.
Spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves were stored in polyethylene bags and without packing for 24 and 48 hours in a refrigerator at 5 and 30 °C in polyethylene bags. The fresh leaves were also dried (oven and sun); blanched (5, 10 and 15 min) and cooked in an open pan and a pressure cooker. The processed leaves were analysed for total and extractable calcium and zinc content. The Ca and Zn content of these leaves varied from 1320 to 2120 and 11.70 to 12.60 mg/100 g DM and the percentage HCl-extractability was 77.82 to 81.92 and 85.16 to 86.15, respectively. No significant effects of drying and storage were observed on total Ca and Zn content and HCl-extractability while blanching and cooking resulted in significant improvement of HCl-extractibility of these two minerals. Thus, cooking and blanching are good ways to improve the HCl-extractibility of Ca and Zn.  相似文献   
109.
Vitellogenin is a female-specific calcium-binding glycolipophosphoprotein synthesized in the hepatocytes of fishes. Its synthesis can be induced in fishes of either sex by estradiol or by xenoestrogens. To study the in vitro synthesis of vitellogenin, different culture conditions were set up using the hepatocytes of Clarias gariepinus. The present study reports on a non-enzymatic procedure for isolation and culture of hepatocytes from the liver of the catfish Clarias gariepinus, in order to study the effects of estradiol on vitellogenin synthesis in vitro. The procedure employs chelating properties of ethylenediamine tetracetic acid to achieve cell viability in excess of 95%. Equal numbers of isolated cells were incubated in different culture media viz. RPMI F1640, Medium-199, and Williams’ Medium E. At 36 h, cell attachment and monolayer formation is faster in M-199 and Williams’ Medium E than in RPMI. In order to study the effects of estradiol on vitellogenin synthesis, the isolated hepatocytes were seeded in Williams’ Medium E in 24-well cell culture plates. 17 β-estradiol (E2) was introduced in the culture plates at different concentrations and for different time periods. The media were assayed for vitellogenin using competitive ELISA. Vitellogenin appeared in the medium after 48 h of incubation with 10−5 M estradiol whereas after 72 h of incubation 5×10−7 M E2 could elicit the synthesis.  相似文献   
110.
Estrogen administration in C. punctatus increases RNA: protein and RNA: DNA ratios and depletes glycogen in the liver. Increase in glucose-6-phosphatase activity accounts for glycogen depletion whereas high activity of pyruvate kinase suggests stimulation of the glycolytic pathway at the pyruvate step to generate ATP and to provide carbon skeleton for the vitellogenin molecule. Five-fold increase in the activity of NADP+-dependant malate dehydrogenase generates NADPH possibly for fatty acid synthesis. Additional energy requirement (NADPH) is met by stimulation of hexose monophosphate pathway as well as NADP+-dependant isocitrate dehydrogenase. Increase in the activity of NADPH-cytochrome c reductase in microsomal fraction suggests stimulation of electron transport chain. Increase in the activity of glutamate pyruvate transaminase can be directly related to the synthesis to specific amino acids needed for the formation of vitellogenin whereas reduction in glutamate oxaloacetate suggests extra hepatic source of amino acids. Reduction in the activity of glutamate dehydrogenase may be due to catabolism.  相似文献   
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