Search PubMed⌕ Search

Biomedical subjects

G Johnson

Publications and source records attributed to G Johnson.

At least 577 records · Page 32Linked to original sources
PubMed1977

Partial trisomy 10p and familial translocation t(7;10)(p22;p12).

A girl with partial trisomy for the short arm of chromosome 10(p12leads to pter) due to mal chromosome segregation in the father 46,XY,t(7;10)(p22;p12) is described. The major abnormalities in this case are: mottled skin, mid-facial hypoplasia, low percentiles for weight, length, and head circumference, and club feet.

Abnormalities, Multiple↗
PubMed1977

Chloroplast membrane sidedness. Location of plastocyanin determined by chemical modifiers.

Intact grana and stroma membranes (outer membrane absent) and detergent or sonication disrupted thylakoid membranes were treated with the hydrophilic covalent chemical modifiers [35S]diazonium benzene sulfonic acid ([35S]DABS) and [14C]glycine ethylester plus 1-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide metho-p-toluenesulfonate (CDIS). Plastocyanin was purified using column chromatography followed by polyacrylamide gel electrophoresis and the incorporation of [35S]DABS and [14C]glycine ethylester into plastocyanin was determined by slicing the gels and counting the radioactivity in the plastocyanin band. Plastocyanin isolated from thylakoids disrupted prior to chemical modification binds two to four times as much of either modifier than the plastocyanin isolated from intact chloroplasts. This ratio is five to ten times lower than the ratio expected for a component buried behind the permeability barrier of a membrane. The data suggest that plastocyanin is partially exposed at the external surface of the thylakoid membrane rather than being completely buried in, or behind, the lipo-protein membrane.

Biological Assay↗
PubMed1977

Improved methods for separation and purification by affinity chromatography.

Defined conditions for simplified Affinity Chromatography suitable for instructional and research purposes, were developed. The standard method of activation of polysaccharide gels using BrCN was modified and improved using a highly buffered reaction solution. A batchwise protocol for the immunoadsorbent isolation of anti-BSA was used (with commonly employed dissociation agents) and comparative data were obtained.

Acetonitriles↗
PubMed1977

Doppler ultrasonic screening prior to venography for deep venous thrombosis.

A total of 244 patients were examined using both ultrasonic Doppler technique and conventional venography for deep venous thrombosis. The Doppler examination was 93.8% accurate overall in detecting the condition, with a specificity of 96% and sensitivity of 85.7%. Indications for venography after Doppler evaluation include: (1) a positive or equivocal Doppler examination; and (2) critically ill patients with negative Doppler results where absolute diagnostic accuracy is essential. Had these criteria been followed in this study, 174 normal examinations would have been avoided and only six large vein thrombi (ileofemoral or popliteal) in 244 examinations would have been misdiagnosed.

Diagnostic Errors↗
PubMed1977

Chronic hepatic encephalopathy. A psychometrical study.

Psychometric tests were performed in 41 patients with cirrhosis of the liver and suspected hepatic encephalopathy and compared with EEG-examinations and clinical investigations. Marked intellectual impairment was noted frequently even when the clinical investigation was normal. This difference was mainly due to the preserved verbal ability of the patient. The etiology of the cirrhosis did not influence the test results. Male cirrhotic patients with and without alcoholism showed significantly more intellectual impairment then alcoholics without cirrhosis. Patients Patients with constructed porto-systemic shunts showed only slightly reduced intellectual ability compared to those without shunts.

Adolescent↗
PubMed1977

Large vessel impedance in peripheral atherosclerosis.

Recent studies based on an animal model of arterial stenosis have shown that large vessel impedance (ZL), determined from the high-frequency vascular hydraulic impedance of a stenotic femoral arterial bed, is linearly related to the large vessel stenotic resistance, and somewhat independent of distal (small vessel) arteriolar resistance. To determine the applicability of these findings on human subjects with stenotic atherosclerotic lesions, ZL was determined in the femoral arteries of 17 patients (at the time of reconstructive operations) with no (N), mild (AS), and severe (occlusive) atherosclerotic (ASO) disease, and in a group of patients before and after femoral-to-popliteal bypass procedures (FEM-POP). Data were collected under steady-state conditions (SS) and during peak flow after a 30 mg bolus intra-arterial administration of papaverine hydrochloride (PAPAV). The ZL was found to be significantly greater (P less than 0.05) for the ASO group than for the N group at SS and after PAPAV administration. There was no significant difference in ZL between the SS and PAPAV conditions for all groups. The ZL decreased significantly (P less than 0.01) from the pre- to post-bypass conditions (with and without the stenosis), at steady-state and after papaverine hydrochloride administration. Large vessel impedance appears to provide a reliable index of the severity of a large vessel atherosclerotic stenosis, and is indpendent of small vessel resistance in humans. These findings are consistent with those of previous experimental animal studies.

Adult↗
PubMed1976

A 46,XY, del(18)(pter leads to p1 100:) cebocephalic child from a 46,XX,t(12;18)(18pter leads to 18 p 1100:: 12qter leads to 12pter) normal parent.

A normal female with an 18p--chromosome but without any feature of the 18p--syndrome produced a cebocephalic child whose karyotype included an 18p--chromosome. Evidence is presented that the normal female is a nonreciprocal translocation heterozygote resulting from the short arm of one chromosome 18 becoming attached to the long arm of a chromosome 12.

Abnormalities, Multiple↗
PubMed1976

Controlled evaluation of the beta adrenoceptor blocking drug oxprenolol in anxiety.

An investigation of the effectiveness of the beta adrenoceptor blocking drug oxprenolol in the treatment of primary clinical anxiety is reported. A controlled double-blind evaluation of oxprenolol versus diazepam and placebo was carried out. The results of the trial showed diazepam to be generally more effective and to produce a more rapid onset of symptom reduction than oxprenolol. The role of beta adrenergic blocking drugs in the treatment of clinical anxiety and related syndromes is discussed.

Adult↗