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191.
The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2α analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows.  相似文献   
192.
The purpose of this study was to investigate the concentration of polyunsaturated fatty acids (PUFAs) in subcutaneous fat and the relative amounts of PUFAs in plasma in two groups of dogs. Group 1 included dogs with a good skin and coat condition. Group 2 was comprised of dogs with pruritus and compatible clinical signs of atopy. The fatty acid composition of the total lipid fraction was analyzed by gas chromatography. In subcutaneous fat, the concentration of adrenic acid (22:4n-6) was lower in the group of pruritic dogs compared to dogs with healthy skin. The amount of dihomogammalinolenic acid (20:3n-6; DGLA) in plasma lipids from pruritic dogs was higher than in dogs without skin problems.  相似文献   
193.
X Q Gao  L Bj?rk 《Fitoterapia》2000,71(1):19-24
To investigate the variations of active compounds between species, varieties and individuals of Valeriana cultivated under the same environmental condition, the contents of valerenic acid derivatives and valepotriates in rhizomes and roots of different plant material were analysed by a HPLC method. Different species or varieties of Valeriana yielded 11.65-0.15 mg/g of valerenic acid derivatives, and 1.81-0.03 mg/g of valepotriates. The variation between individuals of one commercial cultivar of V. officinalis ranged from 12.34 to 3.01 mg/g of valerenic acid derivatives, and 3.67-0.92 mg/g of valepotriates. Individuals from self-pollinated mother plants, normal or regenerated, showed a similar variation. The variation of micropropagated plants was much less than the seed propagated plants. The ratio of mean values between valerenic acid derivatives and valepotriates was similar in all groups (3 < ratio < 8) except one group of micropropagated plants (ratio > 20).  相似文献   
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Artemisia annua L. is an aromatic-antibacterial herb that destroys malarial parasites, lowers fevers and checks bleeding, and of which the secondary compound of interest is artemisinin. The objective of the present study was to determine yield, yield components and artemisinin content of A. annua L. grown under four nitrogen applications (0, 40, 80 and 120 kg ha−1) in the Çukurova region of Turkey in 2004 and 2005. Field trials were conducted at Çukurova University, Agricultural Faculty Field Crops Department. In the study, plant height, number of branches, fresh herbage yield, dry herbage yield, fresh leaf yield, dry leaf yield, essential oil content and artemisinin content (by high performance liquid chromatography, HPLC) were examined. By analysis of variance, nitrogen doses had no any statistical effect on the traits investigated except for artemisinin content. Artemisinin content of the dried leaves were significantly affected by nitrogen applications, which varied from 6.32 to 27.50 mg 100 g−1. Contents were from 120 and 80 kg ha−1 nitrogen for the years of 2004 and 2005, respectively.  相似文献   
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Eleven cows in late lactation were exposed to butyric acid for three weeks and were compared to five controls. Two intraruminal doses were daily applied, that is 1.0 g/kg B.W. of butyric acid to six animals and 1.0 g/kg B.W. of sodium butyrate to another five. Decline in milk yield was clinically recorded in response to butyric acid, while muscle tremor and diarrhoea resulted additionally from sodium butyrate. Behaviours of the clinico-chemical parameters of beta-OH-butyrate, glucose, free fatty acids, bilirubin, ASAT, gamma-GT, AP, and cholesterol were comparable to those in fattening bulls. Liver damage was not safely established. Some of the clinico-chemical alterations were more strongly pronounced after administration of sodium butyrate. One cow fell ill with ketosis under butyric acid load.  相似文献   
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