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61.
OBJECTIVE: To assess the effectiveness of cholecalciferol (D3) doses for maintaining adequate vitamin D status in crias and adult female alpacas at pasture. DESIGN: A field experiment during winter and early spring in a herd on a farm in South Australia. ANIMALS AND PROCEDURE: Crias, usually less than 6 months of age and female alpacas, aged 2 to 6 years, were given a single subcutaneous dose of 0, 1000 or 2000 IU D3/kg body weight. Plasma concentrations of 25-hydroxycholecalciferol (25-OH D3), phosphorus, calcium and vitamins A and E and alkaline phosphatase activity were measured at intervals over a period of 16 weeks after treatment. RESULTS: Crias not given a vitamin D supplement had reduced growth rate during winter and one animal showed clinical signs of rickets. Vitamin D treatment had no effect on the body weight of mature females. Vitamin D supplements increased the 25-OH D3 and phosphorus concentrations in plasma of both crias and adult females; alkaline phosphatase activity was not affected by treatment. CONCLUSION: It is suggested that for alpacas in southern Australia a subcutaneous dose of 1000 IU D3/kg body weight to crias in late autumn and again in mid winter and to adult females in mid winter should prevent vitamin D inadequacy.  相似文献   
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Acyl-CoA: cholesterol acyltransferase (ACAT), which plays a role in the absorption, storage, and production of cholesterol, has been explored as a potential target for pharmacological intervention of hyperlipidemia and atherosclerotic disease. In our search for ACAT inhibitors from natural sources, the petroleum ether extract of Panax ginseng showed moderate inhibition of ACAT enzyme from rat liver microsomes. Bioactivity-guided fractionations led to the isolation of one new polyacetylenic compound, (9R,10S)-epoxy-16-heptadecene-4, 6-diyne-3-one (1), in addition to the previously reported polyacetylenic compounds 2 and 3. Their chemical structures were elucidated on the basis of spectroscopic evidence (UV, IR, NMR, and MS). The compounds 1, 2, and 3 showed significant ACAT inhibition with IC(50) values of 35, 47, and 21 microM, respectively.  相似文献   
64.
A search was made for 26Mg (26Mg*) from the decay of 26Al (half-life = 0.73 million years) in Al-rich objects from unequilibrated ordinary chondrites. Two Ca-Al-rich inclusions (CAIs) and two Al-rich chondrules (not CAIs) were found that contained 26Al when they formed. Internal isochrons for the CAIs yielded an initial 26Al/27Al ratio [(26Al/27Al)0] of 5 x 10(-5), indistinguishable from most CAIs in carbonaceous chondrites. This result shows that CAIs with this level of 26Al are present throughout the classes of chondrites and strengthens the notion that 26Al was widespread in the early solar system. The two Al-rich chondrules have lower 26Mg*, corresponding to a (26Al/27Al)0 ratio of approximately 9 x 10(-6). Five other Al-rich chondrules contain no resolvable 26Mg*. If chondrules and CAIs formed from an isotopically homogeneous reservoir, then the chondrules with 26Al must have formed or been last altered approximately2 million years after CAIs formed; the 26Mg*-free chondrules formed >1 to 3 million years later still. Because 26Mg*-containing and 26Mg*-free chondrules are both found in Chainpur, which was not heated to more than approximately400°C, it follows that parent body metamorphism cannot explain the absence of 26Mg* in some of these chondrules. Rather, its absence indicates that the lifetime of the solar nebula over which CAIs and chondrules formed extended over approximately5 million years.  相似文献   
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One hundred veterinarians and 100 breeders of traditionally docked dogs from Queensland were surveyed by telephone to determine their attitudes towards tail docking. Eighty-four percent of the breeders surveyed were in favour of docking, whereas 83% of veterinarians were opposed to the practice. Most pups were docked between 1 and 3 days of age. All veterinarians surgically amputated the tail, whereas 16% of breeders applied rubber bands to the tail. Seventy-six percent of the veterinarians, but only 18% of the breeders believed that docking caused significant to severe pain. No veterinarians, but 25% of the dog breeders believed that docking was painless. Although recent changes to the Queensland Canine Control Council's rulings allow dogs with intact tails to be shown in traditionally docked classes, the requirement of breed standard was cited as the major reason for tail docking by both breeders and veterinarians.  相似文献   
67.
In southern Australia, cattle at risk from selenium (Se) deficiency can be given an oral dose of supplements that are effective in maintaining adequate Se status for between 9 and 12 months. The present study was undertaken to assess the duration of the effect of parenteral barium selenate (BaSe) in raising the Se status of cattle at pasture in an area of marginal Se deficiency. The BaSe was given subcutaneously to Hereford heifers, using an 18-gauge needle. Cattle had regular blood sampling to assay Se, from 8 days before dosing to 1155 days afterwards. Results show that a single injection of BaSe was effective in elevating blood and plasma Se concentrations to normal values for at least 2 to 3 years, when given to beef cattle of low normal Se status. We suggest that a prophylactic dosage of 0.5 mg Se/kg body weight as BaSe should be given every 2 years to prevent Se inadequacy in beef cattle grazing pasture of marginal Se content.  相似文献   
68.
The expression of human complement regulatory proteins (hCRP; hDAF, hCD59, and hMCP) in pig tissues has been suggested as one of strategies to overcome the hyperacute rejection (HAR) in pig‐to‐human transplantation. Expression of human tissue factor pathway inhibitor (hTFPI) in porcine endothelial cells has been suggested as a remedy to overcome microvascular thrombosis. To investigate the effects of these combined transgenes, we established transformed pig cells expressing human decay accelerating factor (hDAF) under the control of enhancer promoter (5′LTR‐PCMVIE), and the fusion protein (hTFPI/hCD4) consisting of the functional domains (K1 and K2) of hTFPI and membrane‐tethering domains (D3 and D4) of hCD4 under the control of PCMVIE. Transgenic pigs were generated with the transformed porcine cells through somatic cell nuclear transfer (SCNT) technology. Analysis of quantitative PCR and real‐time quantitative RT‐PCR showed that four copies of hDAF were integrated and 391 copies of hDAF mRNA expressed in the cells of the transgenic pig. The enhancing activity of 5′LTR was approximately 2 fold compared to CMVIE promoter only. The cell viability test showed that more than 80% of ear cells were viable in the presence of 50% human serum. The chromogenic substrate assay and immunocytochemical staining with tail cells showed that the TFPI activity of fusion protein was observed on the cell membrane. The membrane localization of hDAF and hTFPI proteins was observed by immunocytochemical staining, and the expression of transgenes in heart and liver tissues was also confirmed by immunohistochemistry.  相似文献   
69.
The purpose of our study was to create a novel rat aorta stent implantation model. Stainless steel bare metal stents (BMS) or paclitaxel-eluting stents (PES) were implanted in male Sprague-Dawley rats (BW 400 ± 20 g). Two and four weeks after stent implantation, the aorta were collected, fixed with 2% glutaraldehyde, and cut into two segments. One segment was used for scanning electron microscopy analysis to evaluate re-endothelialization, and the other segment was used to calculate the neointimal area. At 2 weeks after stenting, the appearance of neointimal hyperplasia was less in the PES group than in the BMS group. At 4 weeks after stenting, no significant difference in neointimal hyperplasia was observed between two groups. On the other hand, the PES group showed more thrombus formation and less re-endothelialization compared to the BMS group. This study demonstrated the ability of a novel rat model of aorta stenting via a common carotid artery to measure the efficacy and safety of commercially available drug-eluting stents.  相似文献   
70.
Responses of pot-grown persimmon trees (Diospyros kaki cv. ‘Fuyu’) with two different leaf/fruit (L/F) ratios and three different fertigation levels were studied. On July 2, the L/F ratios of 4-year-old trees were adjusted to 20 and 10 by fruit thinning. From July 4 to August 26, each pot was fertigated with a solution containing 0–0 g (none), 10–8 g (medium), or 20–16 g (high) of nitrogen (N) and potassium (K), respectively. The L/F ratio of 10 resulted in higher yields but smaller fruits containing lower soluble solids than the ratio of 20. The non-fertigated trees with the L/F ratio of 10 produced the smallest fruits, but the medium fertigation increased the size of the fruit at this ratio. The high fertigation level decreased fruit skin color at both ratios. Fruit dry weight increased the most among the tree components, accounting for 48–57% of the tree total dry weight at the L/F ratio of 20 and for 64–72% at the ratio of 10. The increase in tree total dry weight at the ratio of 10 was greater than that at the ratio of 20. The trees receiving medium fertigation had higher tree total dry weights than those receiving high fertigation, especially at the ratio of 10. As the L/F ratio changed to 10 from 20, the percentages of N and K partitioned to fruits in the non-fertigated trees increased from 38% to 51% and from 67% to 96%, respectively, of the tree total N and K increases; the percentage decreased with increasing fertigation level. Although fertigation significantly increased total N and K contents of the tree, the increase in K at the ratio of 10 was less in high fertigation rather than in the medium level. The results indicated that adjusting supplemental N and K was necessary to ensure fruit growth and N and K accumulation for trees with high fruit loads, but high levels of fertigation are not necessarily preferable.  相似文献   
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