HE last few years have witnessed the accumulation of a considerable body experimental data dealing with the isolation of mitochondrial mutants in yeast conferring resistance to various inhibitors and with the results of two, three or four factor crosses using these mutants as genetic markers. All these results can be classified as belonging to two types of experimental approaches: one based ess...

The dependence of the PMR spectra of three purine nucleosides (inosine, adenosine and deoxyadenosine) on temperature, concentration and addition of benzene (0.12 molal) has been investi­ gated in aqueous solution. The interaction of benzene with the nucleosides is deduced from the spectra. Enthalpies of self association have been determined as 2.2±0.1 kcal-mole-1 for dA and I. The corresponding...

BACKGROUND A study was undertaken to see whether the prevalence of asthma has changed since a survey was conducted in 1988, using the same methods that showed an increase during the previous 15 years. METHODS A survey of 12 year old children was conducted in schools in South Wales where surveys had taken place in 1973 and 1988. The survey comprised a parentally completed questionnaire and an ...

cytochemical techniques at the fingertips of electron microscopists. Most available methods, however, are by no means routine, and the neophyte cytochemist is misled by the claim that the books were designed to "enable the worker to prepare his specimens without outside help." Regrettably, Vol. III does not live up to the standard of its predecessors. Nevertheless, numerous gems of advice can b...

The survey of laboratories in 1970-72 was continued by a questionnaire to members of the Association of Clinical Pathologists covering the next two years. Hepatitis B accounted for 14 of the 32 cases reported from 28 laboratories. A moderate excess of laboratories reporting hepatitis tested speciments from transplant units. The average attack rate for staff of all types was 143 per 100 000 with...

specifically shown. Table ;1 shows, for example, that 50 percent of the 163,429 former beneficiaries whose benefits terminated at age 18 were male. Table II indicates that one standard error is 2.3 percent. Thus, with 95 percent confidence the percentageof male beneficiaries in this group lies between 45.4 and 54.6. The following procedure may be used to make a rough determination of the statis...