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Biomedical subjects

C Friedlander

Publications and source records attributed to C Friedlander.

5 recordsLinked to original sources
PubMed1990

Statistical models for evaluating the penetrating ability of endodontic instruments.

An in vitro study was conducted to evaluate the penetrating ability of hand instruments (No. 10 K-file and "Pathfinder") and an automated device with a No. 08 (Canal Finder System) file in 270 extracted curved and narrow molar roots. The roots were randomly allocated to six groups, each one corresponding to a different permutation of the three instruments. The experiment was performed in three sequential stages, and Stages II and III were undertaken only in roots where no apical penetration was achieved in the previous stage(s). Statistical models were designed to fit the resulting clinical data. The No. 08 Canal Finder System and No. 10 K-file proved to be similar in their penetrating ability in Stage I (with estimated probabilities of 71.1% and 68.8%, respectively). The No. 08 Canal Finder was found to be the most efficient in Stage II and especially in Stage III, with a probability of penetration of 20.7%, compared with 9.8% for the "Pathfinder" and 7.4% for the No. 10 K-file.

Dental Pulp Cavity↗
PubMed1983

Evidence that natural selection acts on silent mutation.

Analysis of nucleic acid sequence data of mammalian hemoglobin, yeast cytochrome c, and human interferon reveals strong biases in favor of specific codons. These biases do not appear to dissipate over time, suggesting that an indirect form of selection acts on silent mutations. The data are compatible with the "bootstrapping" hypothesis that silent mutations which alter the rate of evolution can hitchhike with traits whose appearance they facilitate. Selection involving modulating effects of codon usage on gene expression may also be involved, but the data appear to exclude simple maximization of gene expression.

Animals↗
PubMed1979

Osteogenesis by periosteal transplant. Experimental study of spinal fusion in rats.

Autogenous transplantation of periosteum was performed in 60 rats. Periosteum was transferred from the femur to the spinal column in the region of thoracic vertebra 8 to lumbar vertebra 2. Follow-up included histological examination and microradiography. New bone formation occurred late and the bones were of a heterotopic nature; a solid arthrodesis was not achieved. Free periosteal grafts do not exhibit the relatively predictable behavior of periosteal flaps. Greater understanding at the biomolecular level may be required before free periosteal grafts can be introduced into routine clinical practice.

Animals↗
PubMed1975

Dynamic repair of acromio-clavicular dislocation.

Twenty patients with complete acromio-clavicular dislocation treated between 1967 and 1973 were reviewed with a follow-up time of from 1-6 years, the average being 3 years. They were treated by transposition of coraco-brachialia, short head of biceps and a third of pectoralis minor from their origin in the coracoid process to the clavicle together with repair of the acromio-clavicular joint. The results were evaluated according to pain, motion, deformity and x-rays with 90 per cent excellent results, 5 per cent fiar and 5 per cent poor. Discussion of the other types of treatment is presented.

Adolescent↗