Biomedical subjects

R M Irving

Publications and source records attributed to R M Irving.

58 records · Page 4Linked to original sources

PubMed1990

A randomized comparison of manipulation of the fractured nose under local and general anaesthesia.

Reduction of simple nasal fractures may be performed under local or general anaesthesia: the latter is by far the most popular method in Britain, though why is hard to define. We have attempted to compare the 2 approaches by means of a randomized, prospective trial. Fifty consecutive, adult patients with radiologically proved fractures of the nasal bones were randomized to a local or general anaesthesia group and underwent manipulation with Asch's and Walsham's forceps between 7 and 15 days post-injury. Analysis of results at 4 h and 8 weeks post-operatively showed no significant benefit conferred by fracture reduction under general anaesthesia as opposed to local anaesthesia with respect to post-operative airway patency or cosmesis. It is suggested that significant benefits can be obtained in terms of patient convenience and cost effectiveness if nasal fractures are reduced under local anaesthesia as an outpatient procedure.

Adult↗

PubMed1969

Characterization and Role of an Endogenous Inhibitor in the Induction of Cold Hardiness in Acer negundo.

An inhibitor extracted from short day treated Acer negundo leaves was compared to abscisic acid in 4 different solvent systems. The chromatographic properties of abscisic acid and the inhibitor were in very close agreement. Treatment of Acer negundo plants under non-hardening preconditions (long days) with either the inhibitor or abscisic acid increased hardiness after a hardening period of 3 weeks at 40 degrees . A gibberellin-inhibitor relationship was further studied by making comparison of extracts of plants subjected to either 4 weeks of long days, long days + 5 degrees nights, or short days. These tests indicated that gibberellin-like activity was greatest when the treatment included long days. Abscisic acid-like levels were highest when the treatments consisted of short days or long days + 5 degrees nights. Since the latter groups are the most capable of developing hardiness, the hardening process appears to be more closely related to a build-up of abscisic acid levels than a reduction of gibberellin levels.

Journal Article↗

PubMed1968

Regulation of Cold Hardiness in Acer negundo.

The application of gibberellin to Acer negundo either during or after a short photoperiod strikingly lowered the amount of hardiness obtained after 4 weeks in darkness at 5 degrees . Two growth retardants, B9 and Amo 1618, the latter of which interferes with gibberellin synthesis, brought about hardiness increases under long photoperiods. The naturally occurring inhibitor, dormin, also increased hardiness under the usual inhibiting influence of long photo-periods. Extracts from plants given long or short days had gibberellin-like compounds in largest quantities during LD and lowest quantities under SD, while the inverse was true for the inhibitor.

Journal Article↗

PubMed1967

Environmental control of cold hardiness in woody plants.

The development of cold hardiness in 2 woody plant species (Acer negundo and Viburnum plicatum tomentosum) was shown to be independent of the induction of bud dormancy. Substantial hardiness levels were obtained under controlled conditions with long days and certain low temperatures-without dormancy development as a prerequisite.Low temperatures given during the dark period with long days induced hardiness to a level not significantly different from that of short days. Giving plants continuous 10 degrees temperatures under long days forced plants to harden as if they were under short days, even though they were not dormant.Development of hardiness was shown to be a photoperiodic response. Increasing weeks of short days, followed by a low temperature hardening period in darkness, brought about a progressive increase in hardiness. The short day stimulus could be reversed by long days. Following 6 weeks of short days, the rate of hardening in darkness at 5 degrees was over twice that of plants previously exposed to long days.

Journal Article↗