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Biomedical subjects

J D Smith

Publications and source records attributed to J D Smith.

At least 343 records · Page 19Linked to original sources
PubMed1978

Cloning of nematode tRNA genes and their expression in the frog oocyte.

Transfer RNA genes of the nematode Caenorhabditis elegans have been cloned in E. coli using the plasmid Col E1 as vector. The tRNAs coded by 3 hybrid plasmids were purified by hybridisation of labelled nematode tRNA with the plasmid DNAs. Each plasmid appears to code for a single distinct tRNA species. The expression of the cloned DNAs was analysed in vivo by injection into nuclei of Xenopus laevis oocytes. Evidence is presented which suggests that these nematode tRNA genes are accurately transcribed and processed in frog oocytes. Analysis of one hybrid plasmid shows that a 300 base pair DNA fragment contains both the structural gene and those regions required for its transcription in vivo. The results show that cloned eukaryotic DNAs from a heterologous source can be tested for functional gene activity in X. laevis oocytes.

Animals↗
PubMed1977

Soft tissue ameloblastoma in a 92-year-old woman.

Ameloblastoma is a rare epithelial neoplasm that most commonly is found within the bony structure of the jaw. Soft tissue ameloblastomas are rarer. Only nine well-documented cases are found in the reviewed world's literature. It is our purpose to report the clinical and morphological features of a gingival ameloblastoma in a 92-year-old woman.

Aged↗
PubMed1977

Perforating granuloma annualare.

Described is a 37-year-old male patient with signs and symptoms of localized perforating granuloma annulare (PGA) on the dorsa of his hands, fingers, elbows, and extensor forearms. PGA usually occurs primarily on the extremities, but the condition may be generalized. Review of the literature indicates that the cause and pathogenesis of this entity remain obscure. Sunlight may exacerbate PGA. Therapeutic success has been obtained with topical steroids with occlusion and with systemic prednisone. Our patient showed no response to liquid nitrogen but responded satisfactorily to topical steroids with occlusion.

Adult↗
PubMed1977

Cranial and dental anomalies in three species of platyrrhine monkeys from Nicaragua.

This paper presents information on the cranial and dental anomalies observed in the crania of three species of platyrrhine monkeys collected in Nicaragua. Cranial anomalies that are discussed include plagiocephaly, bregmatic fontanelle bones, Wormian bones, cranial trauma, and heterotopic bones. Among the dental anomalies that were studied were the following: crazing caries, periodontal and pulpal disorders, alveolar thinning, mechanical loss, excessive attrition, shear bite, impacted molars, supernumerary teeth, congenital agencies, congenital crown aberration, and irregular placement.

Alouatta↗
PubMed1977

Intracranial and extracranial neurogenic hamartoma.

A case of neurogenic hamartoma involving the middle cranial fossa, nasopharynx, and left anterior cervical region and presenting at birth as an obstructive oropharyngeal mass is described. Special management included Gelfoam embolization of the vascular supply, control of airway and feeding, assessment of biological activity of the mass, and appropriate staging of the procedure with neurosurgical, head and neck surgical, and radiological support.

Embolization, Therapeutic↗
PubMed1977

Pseudofolliculitis capitis.

Pseudofolliculitis of the bearded area is a common dermatoses among black men. Acne keloidalis probably represents this same condition, but is located in the nape area. Pseudofolliculitis of the pubic area (pseudofolliculitis pubis) has been reported. We wish to report pseudofolliculitis including the entire scalp and to add the term pseudofolliculitis capitis for this heretofore unreported entity.

Child↗
PubMed1977

Perceptual decentering in EMR and nonretarded children.

Perceptual decentering was examined in nonretarded children, EMR children equated for CA, and EMR children equated for MA. Perceptual decentering was measured by the number of part, whole, and integrated responses to a modification of the Picture Integration Test. MA peers (nonretarded and EMR children of equated MA) produced a significantly greater number of decentered (integrated) responses than did EMR children equated with the nonretarded children for CA. The results indicated that perceptual decentering is more fundamentally related to MA than to CA in EMR children.

Child↗
PubMed1977

EMR and nonretarded children's reactions to contradiction.

Sensitivity to logical contradiction, as manifested by surprise reaction to the Jastrow illusion, was investigated in nonretarded children, EMR children equaled for CA, and EMR children equated for MA. Each subject was asked to select the "big" ring segment; then the position was reversed and the subject was asked to identify the "little" segment. The lower segment in this illusion always appears to be larger. Changing position results in what was previously identified as big by the subject now appearing to be little. MA-matched peers (nonretarded and EMR children) performed at a similar level on the task and at a significantly higher level than EMR children equated with the nonretarded children for CA. These results indicated that sensitivity to logical contradiction is more fundamentally related to MA than to CA in EMR children when their performance is compared to that of nonretarded children.

Child↗
PubMed1976

Transbronchial biopsy via flexible fiberoptic bronchoscope; results in 164 patients.

The diagnostic accuracy and complication rate of transbronchial forceps lung biopsy combined with bronchial brushing were analyzed in 164 consecutive patients, of whom 95 had nonmalignant disease and 51 had malignant disease. Eighteen patients with abnormal chest radiographs had normal transbronchial forceps lung biopsies and no established diagnosis. Satisfactory specimens were obtained in 153 patients (93 per cent), with diagnositc accuracies of 62, 64, and 67 per cent, respectively, in infectious, interstitial, and malignant lung disease. The over-all diagnostic accuracy was 57 per cent. Seven patients were diagnosed as having metastatic carcinoma to the lung by transbronchial forceps lung biopsy, but brush biopsy was psoitive in only 3. Of the 23 patients with primary lung carcinoma diagnosed by transbronchial forceps lung biopsy, 21 had positive brush biopsies. An additional 3 patients with bronchogenic carcinoma, however, were diagnosed only by brush biopsy. Fluoroscopy was essential for accurate positioning of the biopsy instrument. Increased risk factors were present in 83 patients (51 per cent), among whom the immunosuppressed group presented special problems. Significant bleeding in 15 patients (9 per cent) was controlled by conservative management. Pneumothorax occurred in 7 patients (4 per cent). There were no deaths. Transbronchial forceps lung biopsy in experienced hands is safe and well tolerated. The physician, nevertheless, must be prepared to handle major complications, especially bleeding. The procedure has a resonable diagnostic yield in high-risk patients who have a variety of lung lesions.

Adolescent↗
PubMed1976

Postoperative chylous fistula prevention and management.

Postoperative chylous fistulas occur as a complication in 1-2% of all radical neck dissections. Twelve cases are reviewed herein. Chylous fistulas are more common with left neck dissections, but 25% occurred on the right side in this series. An intraoperative chylous fistula was recognized and treated in 75% of the cases which later developed a postoperative fistula. Postoperative fistulas may be divided into two groups: minor fistulas may be treated with pressure dressings and repeated aspirations; fistulas which do not respond to conservative management should be re-explored early and the fistula ligated.

Aged↗
PubMed1976

Family planning services for persons handicapped by mental retardation.

The National Children's Center, Inc., and Planned Parenthood of Metropolitan Washington joined in organizing a special family planning service for persons handicapped with mental retardation. The limited utilization, despite considerable community recruitment efforts, and the few problems encountered with patients served suggest that handicapped individuals can be seen at lower cost and at greater efficiency in regularly scheduled clinics, provided staff are attuned to their special needs. Informal interviews with residential center and clinic staff, with parents, and with clients confirm the need for (a) strengthening in-service training in sex education and contraception to prepare potential clients for more effective use of family planning services; (b) counseling with parents who place a high priority on training for independent community living but are reluctant to face the sexuality of their dependent offspring; and (c) increasing community awareness of the legitimate needs and rights of hard-to-reach handicapped persons in preventing unwanted pregnancies.

Adolescent↗
PubMed1976

Larva currens. Cutaneous strongyloidiasis.

Strongyloides stercoralis causes a distinctive form of cutaneous larva migrans that is recognized as larva currens. The rapid rate of intracutaneous migration, the cutaneous localization, the chronicity of recurrence, and the frequency of urticarial reaction justify its presentation as a clinically distinguishable form of creeping eruption. This clinical complex should be identified as a cutaneous sign of systemic disease.

Aged↗