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Biomedical subjects

J Burch

Publications and source records attributed to J Burch.

29 records · Page 2Linked to original sources
PubMed1980

Hemodynamics of sequential bypass grafts in peripheral arterial occlusions.

An experimental model of double arterial occlusion with potential run-off through an intervening arterial segment has been devised to measure the efficacy of sequential bypass grafting in augmenting run-off. Graft flows were augmented in all instances by the addition of a sequential anastomosis. The increases in flow rates ranged from 49 to 182 per cent.

Animals↗
PubMedDate not supplied

Cryopreservation of protonemata of Ditrichum cornubicum (paton) comparing the effectiveness of four cryoprotectant pretreatments.

If an ex situ programme for the conservation of rare and threatened bryophytes is to succeed, a method of long-term, basal storage is required. The aim of this study was to determine the effectiveness of sucrose, ABA and sucrose/ABA combined, as cryoprotectant pretreatments, for the long-term storage of protonemata of the endangered Cornish path moss, Ditrichum cornubicum. This work is a prelude to the in vitro conservation of rare and endangered UK bryophytes. The addition of sucrose and/or ABA in the pre-culture medium, reduced protonemal growth rate. However, pretreatment afforded a high level of protection against tissue damage during dehydration and freezing, with 100 % regeneration of pretreated plants after thawing, compared to 53 % regeneration of controls. Sucrose combined with ABA in the pre-culture medium gave the most effective cryoprotection, with protonemata having fewer necrotic tissues and rapid recovery of growth.

Bryopsida↗
PubMedDate not supplied

Diagnosis and treatment planning for unerupted premolars.

Premolars rank third in frequency after third molars and maxillary canines in impacted or unerupted teeth. Failure to detect and analyze the problem may lead to unnecessary space loss, crowding, or collapse of the dental arch. A diagnostic scheme is presented to facilitate diagnosing and treating unerupted premolars. Important observations include: Diagnosing congenitally missing permanent teeth. Whether the condition is generalized or localized. Whether the succedaneous tooth has a viable form, eruptive potential, and viable orientation Whether the delayed eruption is due to over-retained primary molars such as ankylosis and incomplete root resorption. The amount of space available for the succedaneous tooth to erupt The presence of overlying soft tissue or bone. Space management and proper management of primary molars will frequently facilitate uneventful eruption of premolars. Orthodontic guidance of eruption is rarely indicated if problems can be detected early and managed properly. Four case reports elucidate the recommended treatment methods for these commonly occurring unerupted premolars.

Ankylosis↗