Summary. Friesian cows were inseminated with semen mixtures containing equal numbers of spermatozoa from a Friesian and a Hereford bull. The five bulls of each breed gave twenty-five possible combinations. The paternity of calves was established by inspection of colour and conformation. Heterospermic indices were calculated to express the relative ability of sires to father offspring after mixed insemination. There were significant differences between the heterospermic indices of bulls, the maximum observed difference being twenty-one-fold. The indices were consistent over two series. The homospermic index was defined as the 16-week non-return rate after normal single first inseminations. The heterospermic index established differences between bulls more efficiently than the homospermic index; one estimate showed that the heterospermic method needed less than 1/170th the number of inseminations required by the homospermic method. The homospermic index was predictable from the heterospermic index, the regression coefficient having a significance level of 0\m=.\05> P > 0\m=.\025.The initial spermatozoan concentration of a bull's semen (before dilution) was highly correlated with the heterospermic index. Measures of semen quality based on the morphology and staining affinity of spermatozoa predicted heterospermic and homospermic indices non-significantly but in the right direction.
BEATTY, R. A. (1977). 3'-bodies as Y chromosome markers in mature human sperm heads: a quantitative approach. Cytogenet. Cell Genet. 18, 3 3.A report on two live-born (69, XXY) and one still-born (69, XXX) infants. Clin. Genet. 9, 43. med. Genet. 7, 118.
22-2J . Reprod. Fert. 37, 331. metry associated with diploid-triploid mosaicism and large satellites. Lancet i, 80.
The clinical presentation and results of surgery of patients with central protruded lumbar discs have not been well defined or distinguished from studies of patients with lateral herniated discs. Many patients are denied surgical treatment, even though they are incapacitated by pain, because they do not have the classic radiographic findings seen in patients with lateral disc herniation. Sixty-three symptomatic patients with radiographically documented central lumbar disc protrusion were analysed. All patients had failed at least 6 months of conservative therapy. Although lumbar spinal pain was the most common complaint, 24 patients also presented with bilateral leg pain and 33 with unilateral leg pain; 26 had unilateral limitation of straight leg raising. An interesting observation was that unilateral symptoms and dural tension signs can be seen in patients with central disc protrusion. After surgical follow-up for a mean of 51 months, 86% achieved good results when analysed by the Prolo Functional Economic Outcome Rating Scale. It is postulated that pain is mediated by neuropeptides and arachidonic acid degradation products which are a response to mechanical annular injury.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.