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1.
Jennifer H. Riddell Philip J. Whitfield M. A. Balogun Michael C. Thorndyke 《Acta zoologica》1991,72(1):1-5
FMRFamide-like immunoreactivity has been demonstrated in the digenean trematode Echinostoma liei. The functions of FMRFamide-like substances appear to be many and varied within the invertebrates, where they are involved in neurotransmission, cardiovascular regulation, muscular contraction and/or relaxation, and in co-ordination of growth and maturation. It is clearly indicated that FMRFamide-like substances function as neurotransmitter/neuromodulator in E. liei by the abundance of positively stained nerve fibres and perikarya seen throughout the CNS and PNS. A single endocrine-like cell also showing FMRFamide-like immunoreactivity is situated within the muscular cirrus pouch. 相似文献
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The gene encoding human coagulation Factor V (FV), one of the cofactors in the blood clotting process, has been mapped to chromosome 1 by both Southern hybridization to DNA from human-hamster somatic cell hybrids and in situ hybridization. The whole plasmid pUC3A containing a 1.5-kb cDNA sequence for FV was 32P-labeled for Southern analysis and 3H-labeled for in situ hybridization to metaphase chromosomes. The results localized the FV gene to the region of 1q21-25. 相似文献
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A random, unique DNA sequence has been isolated and assigned to human chromosome 8. This sequence (D8MGV1) recognizes two alleles that differ in size by 700 bp. 相似文献
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Zona pellucida-intact ova collected from ewes seronegative to Brucella ovis were exposed in vitro to B ovis and washed 10 times in medium that contained no antibiotics. After exposure and washing, nontransferable ova were cultured for isolation of Brucella , and the viable ova were transferred into seven B ovis seronegative ewes. No pregnancies resulted, thus recipient ewes were bred during the next breeding season, and blood samples were collected for bacteriological and serological examination until one month after lambing. Brucella ovis was isolated from all of the nontransferable ova, indicating that the transferred ova had viable organisms adhered to them. Although no recipient was found to be pregnant at Day 45, all seven ewes responded to the transferred ova by producing anti-Brucella antibodies. With the exception of a ewe that was euthanized early in the project due to a traumatic injury, all recipients lambed normally during the following breeding season. Brucella was not found in any sample collected from ewes or lambs. However, ELISA titers for B ovis remained in the suspicious range and a ewe was positive on the CF test within 2 wk of lambing. 相似文献
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This study was conducted to determine the relationship between testicular shape, scrotal circumference (SC) and sperm production. Twenty-seven mature Holstein bulls were evaluated subjectively and objectively for testicular shape as indicated by testicular length and width, then placed in 1 of 3 groups. Group 1 contained 17 bulls with a normal ovoid testicular shape and a length to width ratio of 1.61:1 +/- 0.01 (SEM). Group 2 was composed of 4 bulls with a long, slender testicular shape and a length to width ratio of 1.95:1 +/- 0.06 (SEM). Group 3 was comprised of 6 bulls with spheroid-shaped testicles and a length to width ratio of 1.3:1 +/- 0.03 (SEM). All the groups were statistically different for length to width ratios (P < 0.05). Length measurements from cranial to caudal pole of the testis proper were also different between groups (P < 0.05). Width or testicular diameter was different between Group 2 and Group 3 at P < 0.05; however, there was no difference between Group 1 and Group 2 or between Group 1 and Group 3. Predicted volumes and weights of testicles were not significantly different between groups. Scrotal circumference measurements were significantly different between groups (P < 0.05). Group 1 had an average SC of 43.07 +/- 0.36 cm (SEM), Group 2 of 39.33 +/- 1.18 cm (SEM) and Group 3 of 46.22 +/- 0.69 cm (SEM). Sperm production for a twice daily, 2-day-per-week collection schedule revealed a statistically significant difference for sperm output. A total of 2742 ejaculates was evaluated. A total of 1818 ejaculates was evaluated in Group 1, 440 ejaculates in Group 2 and 484 ejaculates in Group 3. The mean spermatozoal harvest per day for Group 1 bulls was 13.62 +/- 0.09 x 10(9) (SEM). Group 2 bulls with the longer-shaped testicles produced 14.82 +/- 0.18 x 10(9) (SEM) spermatozoa per day, and Group 3 bulls, with the more rounded testicle shape and the significantly larger SC produced 11.72 +/- 0.64 x 10(9)(SEM) sperm cells per day. All 3 groups were statistically different at the P = 0.05 level. The results suggest that prediction of sperm production may be dependent on factors other than SC, testicular volume, or weight. Testicular shape may influence sperm output in mature Holstein bulls. 相似文献
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Semen was collected from 5 mature beef bulls by electroejaculation before, during, and after 20 days of scrotal insulation. Thermally-induced testicular degeneration was irreversible in 3 of the bulls. Analysis of sperm and seminal plasma polypeptides revealed that 15 to 30 sperm polypeptides and 25 to 30 seminal plasma polypeptides were indistinguishable between bulls prior to the insulation treatment. Changes in the sperm polypeptides pattern appeared as early as 2 days after the insulation treatment and persisted for at least 11 months in 2 of the bulls. In the spermatozoa, there was a detectable loss of 31, 34, 49 and 58 kDa polypeptides and an appearance of 6 to 8 new major polypeptides, ranging from 32 to 83 kDa. The 83 kDa polypeptide was most prominent in the 2 bulls that regained normal sperm motility and morphology following the insulation period. The post-insulation appearance of a seminal plasma polypeptide (circa 60 kDa) was also identified in these 2 bulls. Seminal plasma polypeptides remained qualitatively unaltered by the insulation treatment in the 3 bulls with irreversible testicular degeneration. 相似文献
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