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Biomedical subjects

C H Chang

Publications and source records attributed to C H Chang.

At least 703 records · Page 39Linked to original sources
PubMed1977

Teratogenicity of zinc chloride, 1,10-phenanthroline, and a zinc-1,10-phenanthroline complex in mice.

Zinc chloride, in single doses of 12.5, 20.5 and 25 mg/kg ip on Day 8,9,10, or 11 of gestation in CF-1 albino mice, produced skeletal anomalies without accompanying soft tissue defects. Ripple ribs, the most unusual anomaly, first appeared when the zinc salt was given on Day 9 of gestation in a dose of 20.5 mg/kg, becoming more prevalent when 25 mg/kg of the drug was administered on Day 11.1,10-Phenanthroline, in single doses of 30 mg/kg ip on Day 8,9,10, or 11 of gestation elicited skeletal defects comparable to those caused by zinc chloride as well as soft tissue anomalies, but a significant incidence of the former occurred with this agent only following its injection on Day 8 of gestation. A zinc-1,10-phenanthroline complex in single doses of 50 mg/kg on Day 8,9,10, or 11 of gestation yielded significant incidences of skeletal and soft tissue anomalies only when the complex was administered on Day 8 or 9 of gestation. This dosage level was toxic to both the mother and fetus when given on Day 10 of gestation. However, when the complex was given on Day 8,9,10, or 11 in a dose of 25 mg/kg, neither toxic nor teratogenic effects were observed in the mother or fetus, respectively.

Animals↗
PubMed1977

Conjugated hyperbilirubinemia in infancy associated with parenteral alimentation.

Liver biopsy was performed to exclude anatomic obstruction of the biliary tract in five prematurely born infants who had developed conjugated hyperbilirubinemia during intravenous alimentation with a protein hydrolysate. Each was being treated after having undergone a segmental intestinal resection for necrotizing enterocolitis. Bacterial and viral infections, metabolic disorders, and isoimmune hemolytic disease were excluded as possible causes of jaundice. Light microscopic and ultrastructural analysis disclosed cholestasis and hepatocellular injury without significant inflammatory reaction. Jaundice abated following permanent discontinuation of parenteral alimentation. The jaundice and cholestasis are interpreted to be hepatotoxic effects because of (1) their temporal relationship to the treatment and (2) the presence of hepatocellular damage.

Biopsy, Needle↗
PubMed1977

Preliminary characterization of isoimmunogenic placental antigens in the rabbit.

By isoimmunization of adult virgin female rabbits with rabbit placental extracts we have demonstrated the production of humoral antibody against two antigens, Ag-1 and Ag-2. Neither antigen is a normal serum protein, nor are they allotype proteins. Ag-1 has an alpha-2 mobility and a molecular weights of about 400,000. Ag-2 exhibits a gamma mobility but was not characterized. The antibody activity directed to Ag-1 in immune sera was the complement-fixing IgG fraction. Direct fluorescence-labeled antibody technique revealed that Ag-1 is a ubiquitous intracellular antigen primarily localized in the nucleus. The fast-growing, SV-40 virus-transformed rabbit kidney cell line (TRK-1) expressed much higher levels of Ag-1 than the slow-growing, non-transformed normal rabbit kidney cell line (LLC-RK1). The possibility that elevation of Ag-1 production is associated with rapid cell proliferation is discussed.

Animals↗
PubMed1977

Computed tomography of the breast. A preliminary report.

Initial studies indicate that computed tomography can detect both benign and malignant breast disease in both fatty and dense, thick breasts. CT may also be capable of diagnosing early cancer or a precancerous lesion in women with dysplastic breasts or patients who have had radiation therapy or surgery, whereas some of these lesions cannot be diagnosed by mammography because the breast is too dense.

Breast Diseases↗
PubMed1977

Hyperbaric oxygen and radiation therapy in the management of glioblastoma.

A pilot clinical trial on radiotherapy of glioblastoma with and without hyperbaric oxygen was performed at the Columbia-Presbyterian Medical Center. Eighty previously untreated patients with histologically proved glioblastoma were evaluated; 38 were irradiated under hyperbaric oxygen and 42 (controls) in atmospheric air. The survival rates were calculated according to the actuarial analysis method. At the end of 18 months, the survival rate appeared considerably higher in the oxygen group (28%) than in the controls (10%). At the end of 36 months, no patients in the control group survived, whereas 2 patients in the oxygen group were alive beyond 45 and 48 months, respectively. The median survival time was 38 weeks for those treated under oxygen and 31 weeks for the air control group. Owing to the small population samples and the pilot nature of this study, the difference in survival rates between the two groups was not statistically significant. The toxicity of hyperbaric oxygen was well tolerated by most patients, and the quality of survival in the hyperbaric oxygen group was equal to or slightly better than that of the control group. This pilot clinical study paved the way for further controlled clinical trials of hyperbaric oxygen and oxygen-mimicking drugs, including the electron-affinic compounds that could have differentially sensitized the hypoxic tumor cells.

Adult↗
PubMed1977

A new low dose mammography technique.

Reduction of radiation dosage to patients undergoing mammography is very important, especially when large-scale screening projects for early detection of breast carcinoma are considered. A new low dose mammographic technique employing Kodak XG film and Industrex F2 intensifying screen in a vacuum package has been evaluated in 533 patients. This Kodak system was found to provide excellent diagnostic quality image, and to be an acceptable technique for mammography.

Breast Neoplasms↗
PubMed1976

Alveolar soft part sarcoma.

Alveolar soft part sarcoma is a rare, highly malignant tumor. It usually arises in the skeletal muscles in the extremities of patients in their second or third decade with a female preponderance of 2:1. Three additional cases, including the angiographic findings, have been presented. The literature pertaining to this subject also has been reviewed.

Adolescent↗
PubMed1976

Roentgen recognition of enlarged hilar lymph nodes: an anatomical review.

A new anatomical classification of the hilar lymph nodes, and their usual roentgen distribution, is presented, along with the most appropriate radiographic techniques for their demonstration. The characteristic roentgen appearances of enlarged hilar lymph nodes in various locations are correlated with the differential diagnoses. The appearance of a rounded lobulated mass is the typical radiographic finding of total hilar enlargement. The diagnosis of hilar nodal enlargement is best made from lateral body section radiographs.

Humans↗
PubMed1976

Film mammography: new low radiation technology.

A new mammographic technique with Kodak MIN-R film and a Kodak MIN-R screen in a vacuum package has been evaluated in 607 cases. Direct mammographic comparison is made with the Du Pont Lo-dose system in the first 101 patients. The system provides excellent diagnostic quality images with at least a two-fold reduction in patient exposure compared to other current mammographic techniques.

Female↗
PubMed1976

Congenital levojuxtaposition of the right atrial appendage. Association with persistent truncus arteriosus, type 4.

Congenital levojuxtaposition of the right atrial appendage is a rare malformation most commonly associated with a transposition of the great arteries. We report a case of levojuxtaposition of the right atrial appendage associated with a persistant truncus arteriosus, type 4. Juxtaposition of the atrial appendage is a sign of severe cyanotic congenital heart disease, and this is best diagnosed by a selective right atriogram or superior venacavogram.

Coronary Vessel Anomalies↗
PubMed1976

Fractionation studies on a factor in linseed meal protecting against selenosis in chicks.

Growth rate of Single Combe White Leghorn cockerels fed a casein-gelatin-glucose diet was significantly depressed at two weeks when 10 p.p.m. or more selenium was added to the diet. When 20% linseed meal was included in the diet, growth was not reduced with 10 p.p.m. selenium and only slightly reduced with 20 p.p.m. selenium. Including 20% soybean meal failed to modify the toxicity. Levels of 5 and 10% linseed meal were less effective in counteracting selenosis than was 20%. Fractionation studies showed that a protective factor in linseed meal was extracted by methanol and ethanol and was not destroyed by autoclaving. Ashing the ethanol extract destroyed its activity. The factor was readily extracted by chlorform:methanol (2:1) but less effectively by acetone and diethyl ether. Washed chloroform:methanol extract was inactive but the washings contained the factor. Concentrates of the factor were active at less than 1% of the dry matter of the diet. The results of these studies show that linseed meal contains a heat stable, organic, polar factor that modified selenium toxicity in the chick.

Animal Feed↗
PubMed1976

Influence of carbohydrate source on liver fat accumulation in hens.

Four experiments were conducted with laying hens and one with broiler chicks to investigate the effect of carbohydrate source on fat accumulation in the liver. When corn and wheat in various proportions were fed to laying hens, the percent fat and total fat per liver increased as the proportion of corn increased. In comparison of different cereal grains and wheat samples in isocaloric diets, the total liver fat accumulated was the highest for hens fed grain sorghum, corn or triticale and the lowest for those fed barley, oats or rye. Intermediate levels of liver fat were obtained with wheat and similar liver fat contents were observed with hens fed different samples of West Coast wheat. There was no significant difference in liver fat of groups fed wheat diets made isocaloric with corn oil or animal fat, Liver fat accumulation of broiler chicks fed diets with corn or wheat was not significantly different. No difference in liver weight, liver fat content and total fat per liver was observed among hens fed diets containing either zero, one-half, or all glucose monohydrate substituted for corn. In comparisons of corn or wheat from different geographical area, no difference was observed in liver fat content of hens fed corn grown in Georgia or the Midwest or wheat grown in Georgia or in the Far West. Hens fed diets contaning corn had significantly more liver dry matter, liver fat, and total fat per liver than hens fed the isocaloric diets containing wheat. Considerably more fat accumulated in the livers of hens fed diets containing corn at Washington State University (15.4 to 19.6 g. fat/liver) than in hens fed corn at the University of Georgia (5.4 to 7.2 g. fat/liver), suggesting the existence of unidentified environmental factors affecting liver fat accumulation.

Animal Feed↗
PubMed1976

Effect of calcium propionate on performance of laying hens.

Laying hens kept in individual cages were fed a practical diet supplemented with 0, 0.1, 0.2., 0.4, or 0.8% calcium propionate for a six-week period. Rate of egg production, average egg weight, feed consumption, and body weight change during the experiment were not significantly affected by and dietary treatments. Liver weight, moisture content and fat content were also no significantly affected by dietary treatments. The results show that the performance of normal hens is not changed by calcium propionate supplementation.

Animals↗
PubMed1976

Effect of biotin and niacin on lipid content of livers in the laying hen.

Single Comb White Leghorn layers maintained in cages were fed a corn-soy diet with a simplified vitamin premix for a 12-week experimental period to determine the effect on liver lipid accumulation. Lipid content was only 29.6% of the liver dry matter and, therefore, was in the normal range and less than that seen in hens with fatty liver syndrome. Adding niacin (44 mg./kg.) or biotin (110 mug./kg.) either alone or in combination failed to significantly alter liver weight or liver lipid content. Liver lipid content of hens fed another diet with a more complex vitamin premix also was not significantly different from that of hens fed the diet with the simplified vitamin premix. None of the diets significantly affected egg production, egg weight, feed consumption or body weight changes observed over the 12-week period.

Animal Feed↗