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81.
Barium in southern california coastal waters: a potential indicator of marine drilling contamination
Chow TJ 《Science (New York, N.Y.)》1976,193(4247):57-58
The present barium content of Southern California coastal waters was determined to be 11 to 22 micrograms per kilogram of seawater. These values may be used as base-line concentrations to monitor marine contamination during future off-shore oil and gas explorations. 相似文献
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Discovery of mature freshwater eels in the open ocean 总被引:1,自引:0,他引:1
85.
Effect of oestrous synchrony between embryo donors and recipients,embryo quality and state on the pregnancy rate in beef cattle 下载免费PDF全文
MCC Rodrigues ALM Bonotto DAV Acosta AA Boligon MN Corrêa CC Brauner 《Reproduction in domestic animals》2018,53(1):152-156
This study aimed to evaluate the effect of oestrous synchrony between donors and recipients and the embryo quality on the pregnancy rate in beef cow recipients. The experiment was performed over two years at an embryo transfer (ET ) centre in Southern Brazil. Ninety Aberdeen Angus cows were subjected to superovulation (SOV ) protocols, resulting in the recovery of 1,048 transferable embryos. Eleven groups were formed with intervals of 6 hr, from ?30 to +30 hr, with respect to recipient versus donor oestrous detection. Evaluation of embryo quality was according to the IETS guidelines. The overall pregnancy rate was 52%. Effects related to donor and recipient oestrous synchronization on pregnancy rate were observed (p = .01), ranging from 36% to 50%. The embryo quality rate affected the pregnancy rate, where Grade I resulted in 57% and Grade III in 43% of pregnancy (p < .001). The embryonic state (frozen or fresh) showed no (p > .05) effect on pregnancy rate: 53% for fresh embryos and 44% for frozen embryos. The odds ratio for explanatory variables causing pregnancy indicated that Grade III embryos had 31% less chance of conception compared to Grade I. Thus, oestrous synchrony between donor and recipient, considering ±30 hr apart, can affect the pregnancy rate along with embryo quality. 相似文献
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Interstitial cell-stimulating (luteinizing) hormone was isolated from swine pituitary glands. This protein hormone, having a molecular weight of about 90,000 and an isoelectric point of pH 7.45, was shown to be pure by tests in the electrophoresis apparatus of Tiselius and in the ultracentrifuge as well as by its constant solubility. The hormone stimulated the interstitial tissue of the testis or ovary and caused the formation of corpora lutea provided that maturing follicles were present. Under the conditions described, its minimal effective total dose in hypophysectomized immature male rats was about 1 microgram of nitrogen or 6.7 micrograms of hormone. Extracts of swine pituitary with purely follicle-stimulating effects did not cause oestrus in immature hypophysectomized female rats unless luteinizing hormone was also administered. 相似文献
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Waldner CL Henderson J Wu JT Coupland R Chow EY 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(2):130-132
Blood samples were collected from 1806 pregnancy-tested cows from 174 herds at a northern Alberta auction mart in the fall of 1998. One hundred sixty-two (9.0%) of these samples were positive for antibodies to N. caninum. Thirty-five of 260 samples (13.5%) collected from the same region in the 1980s were also serologically positive for N. caninum. 相似文献
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