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Biomedical subjects

D C Smith

Publications and source records attributed to D C Smith.

At least 217 records · Page 12Linked to original sources
PubMed1989

Learning problems, anger, perceived control, and misbehavior.

Fifty-four students diagnosed as having learning disabilities (LD) and 73 students in regular education were administered the School Anger Inventory and the Perceived Control at School Scale. Teachers and parents rated student deportment and motivation. Predictably, those in the LD sample indicated higher school anger levels and were rated as exhibiting more negative behavior, less positive behavior, and lower motivation for on-task performance. The samples did not differ in their ratings of perceived control, which was moderate, and were given comparable positive teacher ratings for recall of relevant and interesting material. Significant correlations between school anger and behavior were found only in the LD sample, and there was no significant overall relationship between school anger, behavior, and perceived control within either sample. Overall, however, students who reported both a high level of anger and high perceived control were found to exhibit more negative behavior than those with high anger and low perceived control.

Adolescent↗
PubMed1989

Toward a procedure for minimizing and detecting false positive diagnoses of learning disability.

Assessment procedures that can significantly enhance motivation to perform are needed so that poor performance due to low or avoidance motivation is not misdiagnosed as indicating ability deficits or as symptomatic of learning disabilities (LD). In this connection, research is under way to investigate the degree to which a highly motivating computer game learning task can improve differential diagnoses of LD. Findings from the initial investigation indicate that a large proportion of students diagnosed as LD were able to learn effectively when pursuing such a task. The results illustrate the key role motivation plays in determining the validity of diagnostic assessment and demonstrate the potential value of similar tasks for use in differentiating, from among individuals diagnosed as LD, those who do not have impaired learning processes.

Adolescent↗
PubMed1989

Retention of three post and core systems with and without etching.

The retentive strength of post and cores fabricated entirely of composite material was compared to the retentive strength of Para Posts with composite cores in etched and unetched post preparations. Under tensile forces exerted upon the cores, only one post was removed. In all other samples the posts remained firmly embedded within the roots. The core material fractured at the occlusal surface of the roots. The Para Post with Composite core cemented into etched preparations was significantly more resistant to fracture than all other samples.

Acid Etching, Dental↗
PubMed1988

Transfemoral coronary arteriography via a prosthetic aortic bifurcation graft.

Angiographers may inappropriately avoid the transfemoral access route when a prosthetic aortic bifurcation graft exists. An aortofemoral graft will necessitate overdilatation of the femoral puncture site to allow adequate manipulation. If the puncture transverses both walls of the femoral limb of the graft into the native artery, further withdrawal of the catheter will allow reentry into the graft. When an aorta-to-external-iliac, end-to-side graft is present, transfemoral catheterization will frequently result in the guide wire or catheter tip terminating in the occluded common iliac artery. By choosing the proper catheter, entrance into the distal limb of the proximally communicating graft may be achieved. For the unwary operator, these confusing situations may result in failure to properly catheterize the graft. The methods of successfully overcoming these problems are discussed and illustrated.

Aorta, Abdominal↗
PubMed1988

Evaluation of the retention of endodontic implants.

The study investigated the retentive strength of endodontic implants measured by forced removal (pull-out or push-out tests) as a function of implant design and cement type. Smooth-tapered, threaded, and an innovative porous-surfaced implant were evaluated. Specimens were cemented in single-rooted human teeth with five different cements: zinc phosphate, polycarboxylate, glass ionomer, silicophosphate, or AH-26. The results indicated superior retention for the threaded and porous-surfaced implants, and stronger retention with glass-ionomer and AH-26 cements.

Bismuth↗
PubMed1988

Evaluation of shear strength at the cement-endodontic post interface.

The strength characteristics of the cement-implant interface were evaluated for smooth-tapered, threaded, and porous-surfaced endodontic implants with the use of different cements. Specifically, tensile and torsional shear strengths were measured for zinc phosphate, polycarboxylate, glass-ionomer, silicophosphate, and AH-26 cements. The results indicated superior shear strength characteristics for threaded endodontic implants on axial loading. However, this strength was diminished when torsional forces were applied. Porous-surfaced endodontic implants showed strong resistance to both axial and torsional loading.

Bismuth↗
PubMed1988

Psychosocial consequences of mastectomy: levels of morbidity and associated factors.

Psychosocial morbidity was examined in 90 consecutive patients with Stage I or II breast cancer aged under 70 treated by mastectomy. In the two years after surgery, the prevalences of depression and anxiety of clinical degree were generally under 10%--less than half of those reported in early controlled studies in the United Kingdom. However, cancer patients aged under 50 showed significantly higher prevalences compared with cancer patients aged 50 or above and compared with matched control subjects with benign breast disease. Social and work problems were common at all ages. Sexual problems were more severe than mood disturbance. Patients at risk of mood disturbance could be predicted by a combination of age, measures of emotional lability and whether or not they were receiving chemotherapy. The results of this study are consistent with those of other recent reports from the United Kingdom and United States, which show that following mastectomy, mood disturbance of clinical degree may be considerably less common than has previously been supposed.

Adaptation, Psychological↗
PubMed1988

Validity of the General Health Questionnaire and its subscales in patients receiving chemotherapy for early breast cancer.

The performance of the General Health Questionnaire as a case detector was assessed in 75 patients receiving chemotherapy for early breast cancer. The questionnaire and its subscales were found to be valid when compared with observer ratings. The misclassification rate of the 60-item version of the questionnaire was lowest when the standard threshold score for clinical morbidity was doubled to 24. It was lowest for the 28-item version when the threshold score was doubled to 10. Suggested threshold scores for clinical morbidity for the subscales are: anxiety and insomnia subscale 6/7; severe depression subscale 2/3; somatic symptoms subscale 6/7; and social dysfunction subscale 7/8. However, lower thresholds would be appropriate if the questionnaire were used as screening instrument prior to interview by a trained observer.

Adaptation, Psychological↗
PubMed1988

Psychosocial morbidity in patients awaiting breast biopsy.

Psychosocial morbidity was compared in 91 patients awaiting breast biopsy and 30 women awaiting elective cholecystectomy. Somatic symptoms and social dysfunction were prominent in cholecystectomy patients. Patients subsequently found to have benign breast disease had the highest levels of psychological morbidity. Patients found to have breast cancer appeared no more anxious or depressed than those awaiting cholecystectomy. However, within the breast cancer group, patients aged 45 or less were significantly more anxious than those over 45, and a past history of psychological upset, prior to discovery of breast disease, was positively and independently associated with anxiety. Results are consistent with recent research suggesting an association between benign breast disease and a predisposition to psychological morbidity.

Adult↗
PubMed1988

Thiol exchange catalysed refolding of small proteins utilizing solid-phase supports.

The study of isolated snake toxin refolding has been a valuable tool in the understanding of protein folding dynamics. We report here differences in the refolding characteristics of three toxin classes and introduce a novel method for overcoming disulphide mismatching and oligomer formation by utilizing solid-phase thiol exchange gels.

Chromatography, High Pressure Liquid↗
PubMed1988

A comparison between zinc phosphate and glass ionomer cement in orthodontics.

In the past orthodontic band cementation has relied heavily on mechanically retentive cements such as zinc phosphate luting agents. The clinical performance of a glass ionomer cement (GIC), a chemically retentive cement, was evaluated against a conventional zinc phosphate cement (ZP). The recementation values for ZP were significantly higher over a 2-year treatment period than those of GIC. Failures between cement and enamel, and cement and stainless steel were noted for the ZP. Glass ionomer cement had significantly better retentive strength to enamel than to band material. Moisture contamination does not appear to be a problem in orthodontic band cementation with glass ionomer cement.

Cementation↗
PubMed1988

Cancer support groups--who joins and why?

Tak Tent is a cancer support organisation consisting of 14 groups of which 11 are based in Scotland. In 1985, a survey was conducted among those attending the Scottish groups. 146 (79%) of the groups' members completed survey questionnaires. The results showed that Tak Tent's membership mainly comprised cancer patients (36%), relatives of patients (34%) and professionals involved in cancer care (21%). Women outnumbered men 3 to 1 and most of the membership belonged to social classes I, II or III. The groups appeared to be meeting their members' expectations of them to varying degrees. Respondents were satisfied that group membership had allowed them to make new friends, find out more about cancer and meet others facing similar difficulties. They were less certain that participation in a group had enabled them to learn how to cope better with cancer, share their problems with others or provide support for others to the extent they had anticipated.

Adult↗
PubMed1988

Transcatheter embolization facilitating surgical management of a giant inferior gluteal artery pseudoaneurysm.

This article is a report on a case of a giant pseudoaneurysm of the inferior gluteal artery where important features of the diagnosis, with special mention of magnetic resonance imaging and arteriography, are discussed. Surgical therapy is the treatment of choice for these lesions. Historically, proximal arterial control has been the main dilemma in the management of gluteal artery pseudoaneurysm. We found transcatheter embolization to provide optimal control and eliminate the need for preperitoneal or intraabdominal dissection. Surgical repair can then be carried out without risk of intraoperative hemorrhage.

Aneurysm↗