Search PubMed⌕ Search

Biomedical subjects

L Nicholson

Publications and source records attributed to L Nicholson.

At least 37 records · Page 2Linked to original sources
PubMed1997

Transfer index of multiple angulated abutments in the restoration of an edentulous maxilla.

Osseointegration and the replacement of missing dentition with endosseous implants is a viable alternative to conventional prosthodontics with good long-term prognosis. This article describes a procedure for fabricating an index to accurately transfer the ideal position of several 17-degree angulated abutments from the master cast to the mouth in a predictable way. After the final try-in, evaluation of the space available and angulation of the implants is made to choose the appropriate abutments within the contours of the final restoration. A customized index was also developed to accurately transfer the position of those 17-degree angulated abutments from the master cast to the mouth in a precise manner.

Dental Abutments↗
PubMed1997

Evaluating large scale health information systems: from practice towards theory.

With the introduction of large scale health information systems which are incrementally developed from legacy systems, evaluators are faced with difficult methodological and practical problems. Some of the problems involved in multidisciplinary multi-method evaluations care discussed. It is argued that the development of a framework for evaluation is necessary in order to successfully plan an evaluation, understand the implications of the results and make future predictions based upon them. Some suggestions for arriving at such a framework are put forward.

Evaluation Studies as Topic↗
PubMed1997

[Interactive multimedia learning systems in oral medicine: experiences at the Faculty of Oral Medicine of Laval University].

Dental teaching must keep in stride with the latest trends. Evolution and challenge are very much a part of every day life for both students and dentists. At the University of Laval, the faculty of dentistry has developed an interactive multimedia apprenticeship system. This system will be incorporated into the curriculum of Laval's doctor of dental medicine degree, as well as the organizational framework of its continuing education program. It will only be a first step for the faculty's department of oral rehabilitation, which ultimately hopes to see the system used by dental schools across Canada. Known as "Médent," the prototype system is designed to teach the principles of osseointegration, and the rehabilitation of oral function using osseointegrated implants.

Canada↗
PubMed1996

Extending the spectrum of distal arthrogryposis.

We describe a mother and son with multiple, non-progressive, congenital contractures, camptodactyly and absent flexion creases, expressionless face, blepharophimosis, microstomia, and short stature. Although these cases share similarities with the autosomal-recessive Schwartz-Jampel and Marden-Walker syndromes, they have a different mode of inheritance and lack myotonia, one of the most characteristic findings of the Schwartz-Jampel syndrome. Our cases most closely resemble those previously reported as distal arthrogryposis type IIb, although in our patients the proximal joints are severely affected and extraocular involvement is absent. Hearing loss is present in one and cleft palate in the other of our patients; these findings were previously described in arthrogryposis syndromes other than type IIb. We suggest extending the spectrum of distal arthrogryposis to include these manifestations, since there appears to be significantly overlap between the different syndromes.

Abnormalities, Multiple↗
PubMed1996

Bilateral duplication of the primary ulnar ossification center in Ellis-van Creveld syndrome.

A patient with Ellis-van Creveld (EvC) syndrome and bilateral duplication of the primary ulnar ossification center is presented. Abnormal ossification involving secondary ossification centers of the femur and tibia as well as duplication of primary ossification centers in the carpal bones are well described in EvC. No abnormality of ulnar ossification has been noted in patients with EvC or any other skeletal dysplasia. The occurrence of bilateral duplication of ulnar ossification centers extends the clinical findings of the EvC syndrome. The gap between the ossified areas could be misinterpreted as a fracture and thus lead to a suspicion of osteogenesis imperfecta prenatally or traumatic fracture postnatally.

Ellis-Van Creveld Syndrome↗
PubMed1996

The effects of calcium supplementation on ambulatory blood pressure in African-American adolescents.

This longitudinal trial investigated the effects of calcium supplementation on the mean 24-hour blood pressure in African-American adolescents. Subjects were self-identified African-American adolescents from a high school in a suburb of Los Angeles, California. The subjects were randomly placed in a placebo or treatment group (placebo versus 1.5 g of calcium/day x 4 weeks). Follow-up mean 24-hour ambulatory blood pressure (ABP) for both the treatment and control groups was lower than the baseline mean 24-hour ABP. In the treatment group, there was a decrease of 2.2 mm Hg in the mean systolic blood pressure and 0.7 mm Hg in the diastolic blood pressure. Relative to the placebo group, the net change in ABP was -1.7 mm Hg for systolic blood pressure and -0.5 mm Hg for the diastolic blood pressure. There was no statistically significant effect of calcium supplementation on the 24-hour mean ABP. The net effect of supplementation on ABP during waking and sleeping hours also was not significant.

Adolescent↗
PubMed1995

High prevalence of Helicobacter pylori antibodies in an institutionalized population: evidence for person-to-person transmission.

OBJECTIVE: To evaluate the prevalence of H. pylori antibodies in mentally and physically handicapped adults living together in a long-term care facility. METHODS: One hundred twenty-two institutionalized subjects from six living areas were compared to a normal representative Caucasian population obtained by random sampling from the urban population area of Melbourne. Serum samples from 1977 and 1989 from 122 subjects were tested for H. pylori antibody by an ELISA technique. The data were analyzed by Student's t test, chi 2 test and logistic regression. RESULTS: Ninety-two of the 122 subjects (75%) from whom sera was collected in 1989 were seropositive for H. pylori, compared with only 23% in age- and sex-matched control subjects (p < 0.0001). The prevalence of H. pylori antibodies in 1977 was 34% (42/122). Of the remaining 80 seronegative subjects, 51 (61.4%) converted to became positive in the 12-yr interval. The annual seroconversion rate was 7.4%, with an average of 4.25 newly positive subjects each year. The prevalence of H. pylori in 1989 was significantly higher than in 1977 after adjustment for age (odds ratio 2.39, 95% CI 1.1-5.3, p = 0.03). CONCLUSIONS: H. pylori antibodies are significantly more prevalent in institutionalized adults compared with controls from the general population. These data support the hypothesis that H. pylori is acquired by either fecal-oral or oral-oral transmission.

Adult↗
PubMed1994

Risk factors in Klippel-Feil syndrome.

STUDY DESIGN: This study kinematically evaluated radiographs of the cervical spine of patients with the Klippel-Feil syndrome in flexion and in extension to determine alterations from normal motion and potential risk. OBJECTIVES: The results in the study group were compared with those of a control group and with published standards for expected motion of the cervical spine. SUMMARY OF BACKGROUND DATA: The body of orthopedic and neurologic literature suggests a significant problem with neurologic deficit in patients with Klippel-Feil syndrome. No previous study has evaluated the kinematics of the cervical spine with a control group of normal individuals and published standards. METHOD: Lateral flexion-extension radiographs of the cervical spine of 111 patients with Klippel-Feil syndrome were kinematically evaluated to determine the motion of each open interspace and to compare motion with that of a control group and published standards. RESULTS: A statistically significant difference of increased motion per open interspaces in the upper cervical segment was noted in individuals with Klippel-Feil syndrome when compared with the control population. Conversely, total motion of the lower cervical segment was significantly decreased in the Klippel-Feil population when compared with normal controls. Lower segment motion per open interspace was not significantly different when the two groups were compared. CONCLUSION: The results of this study suggest that individuals with Klippel-Feil syndrome with hypermobility of the upper cervical segment are at risk for neurologic sequelae, whereas those with alteration in motion of the lower cervical segment are predisposed to degenerative disease.

Adolescent↗
PubMed1994

Phenotypic variability in the Baller-Gerold syndrome: report of a mildly affected patient and review of the literature.

We report a patient with a mild form of the Baller-Gerold syndrome (craniosynostosis-radial aplasia syndrome). The patient, a 3-year 3 month-old boy, has trigonocephaly with bilateral absent radii and thumbs. His growth parameters and psychomotor development have been normal. No visceral anomalies were found. This patient represents a new case of the rare mild form of the syndrome.

Abnormalities, Multiple↗
PubMed1994

An inspector calls.

Explore the source record for details and available documents.

Management Audit↗
PubMed1992

[Special considerations relating to class 1 and class 2 removable partial dentures in the mandible].

During the rehabilitation of partially edentulous patients, dentists must try to preserve the health of the remaining oral structures. That is why it is essential to make maximum use of the support areas. With removable class 1 and 2 prostheses (Kennedy-Applegate classification), the remaining teeth and the edentulous areas provide support. While virtually no movement from the teeth is noticeable, the tissues covering the edentulous ridges do move in a variable manner. A unit must therefore be designed and built to protect the remaining teeth as well as the residual ridges. The problem is all the more acute for the mandible, since the compressibility of the tissues of the edentulous ridges and remodeling of the bone are greater. Many approaches and techniques have been described in the dental literature: functional impressions, use of appropriate direct retainers, and relining of units, if necessary.

Alveolar Bone Loss↗
PubMed1992

[Clinical characteristics affecting the need for relining of class 1 and class 2 removable mandibular prostheses].

This study attempts to identify, from a sample of people wearing a class 1 or 2 removable prosthetic device on the lower jaw, the extent of the relining needs for these prostheses and their determining factors. Epidemiological methods were used to solve this problem. The relining needs increase with the amount of time elapsed since the prosthetic device was put in the mouth (p = 0.014). As for the other factors reviewed, i.e. class of device, type of retainers used, and occlusion, the authors have identified trends instead of real risk factors, since the impact of this study was significantly reduced due to the small number of people we were able to recruit. It was not always possible, therefore, to verify the statistical meaning of the associations observed. In clinical practice, the treatment plan should include a periodical evaluation of the relining needs. As it is now impossible to establish the approximate time when a prosthetic device may need relining, patients wearing one should be examined periodically and regularly.

Adult↗
PubMed1991

Schistosoma mansoni tropomyosin: production and purification of the recombinant protein and studies on its immunodiagnostic potential.

A cDNA that encodes Schistosoma mansoni tropomyosin, except for 10 amino acids at the amino terminus, has been cloned into a pOTSNCO plasmid vector. Induced expression resulted in a constant level of recombinant protein production. The recombinant S. mansoni tropomyosin was purified from preparative SDS-PAGE gel and by a combination of 20% ammonium sulfate fractionation and fast protein liquid chromatography-ion-exchange chromatography. The purified recombinant S. mansoni tropomyosin was tested as an immunodiagnostic reagent in Western blot and enzyme-linked immunosorbent assays. Sera from individual patients with chronic S. mansoni infection, but not S. haematobium, S. japonicum, parasitic infections other than schistosomiasis, and without infection reacted with the recombinant tropomyosin. The species specificity of S. mansoni tropomyosin suggests that further study of its potential as an immunodiagnostic reagent is warranted.

Animals↗