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Biomedical subjects

G Christensen

Publications and source records attributed to G Christensen.

At least 109 records · Page 6Linked to original sources
PubMed1983

Freezing of mouse embryos in the oviduct.

The survival of 2-cell and 4-8-cell mouse embryos after freezing and storage in liquid nitrogen, -196 degrees C, was examined. Both isolated embryos and embryo-containing oviducts were frozen to -40 degrees C at a cooling rate of 0.3 degrees C/min, and then transferred to -196 degrees C for one week. They were rapidly thawed in a 37 degrees C water bath at a rate of approximately 275 degrees C/min. Survival was assayed by in vitro cultivation of thawed embryos. The results indicated that freezing 8-cell mouse embryos directly or in the oviducts, is a reliable procedure for storing 8-cell embryos. By the procedure used, survival rates of 64% for the directly frozen embryos and 66% for the embryos frozen in the oviducts were obtained.

Animals↗
PubMed1982

Polymyalgia rheumatica syndrome.

Eleven (14%( of 80 patients with polymyalgia rheumatica syndrome (PMR-S) recovered spontaneously within one year; two of them had received repeated injections of depot steroids before remission occurred. The remaining 69 patients, including 14 with giant cell arteritis (GCA), were all treated with systemic glucocorticoids for an average of 30 months (range 3-81 months). Nine of the patients developed side effects from the treatment, which in seven cases were severe osteoporosis and spinal compression. None suffered from loss of vision. The patients' mortality rate and causes of death did not differ from those of the population at large. The diagnostic criteria are discussed, with the omission of those applied for exclusion. Use of the common term PMR-S is preferred, as GCA and polymyalgia rheumatica (PMR) are clinically indistinguishable. Systemic glucocorticoids are urgently needed when arteritis or ocular manifestations are detected or even suspected. In uncomplicated cases of PMR we recommend that trials be made with repeated injections of depot steroids. This procedure could also be used in patients suffering from severe subjective recurrences after cessation of treatment with systemic glucocorticoids, thereby reducing the number of cases where steroid treatment is unquestionably maintained for too long.

Aged↗
PubMed1981

[Pleuropneumonia in pigs due to Haemophilus pleuropneumoniae. I. A bibliographical review (author's transl)].

During the last twenty years pleuropneumonia in pigs, caused by Haemophilus pleuropneumoniae, has spread globally. The increasing importance of the disease within swine production is apparently connected with increasing industrialization and subsequent heavy concentration of a large number of animals in the individual production unit. Haemophilus pleuropneumoniae seems to be specific for pigs. Several more or less pathogenic serotypes of the bacterium are known. Serotype 2 as occurring in Denmark is primary pathogen for pigs which have not previously been in contact with the infection. Immunity of varying strength and duration is left after recovery. Prolonged immunity in an animal is presumably dependent on latent infection or on repeated infections. Normally there is a large number of latently infected animals in attacked herds. Such animals, especially sows and boars, represent a potential infection reservoir which might be the basis of new clinical outbreaks under conditions of reduced herd immunity or of compromised general resistance of animal groups. Clinical disease is most frequently seen in young pigs and fatteners, as piglets are generally protected by maternal antibodies. Acute pleuropneumonia is characterized by high temperature, lost appetite, light cough and often vomiting. Morbidity is high, especially by new-infection where there may also be considerable mortality if adequate antibacterial therapy is neglected, however, normally the disease implies low mortality. The pathological lesions are localized to the respiratory organs. The lungs are the seat of fibrinous necrotising pneumonia (red, grey hepatization), more or less extensive, most frequently of the diaphragmatic part of the lung. Furthermore fibrinous, later on fibrous pleuritis and pericarditis may be seen. The fibrous pleuritis may be of decisive diagnostical value when established with high frequency in baconers. The disease causes losses as a consequence of increased use of medicine and reduced daily weight gain in fatteners. Optimum environment and feeding conditions will reduce such losses considerably. The use of commercially available vaccines makes it possible to fortify specific resistance against the disease in exposed groups of animals. In small herds with few infected animals the infection may be eliminated by discarding seropositive animals, combined with strategic medication. Elimination of the infectious agent in large herds can only take place by replacing all animals by an SPF-herd.

Animals↗
PubMed1979

Corrective socialization in foster care of children.

While the phrase, "interminable foster care" is becoming a damning cliché in the dialogues of juvenile courts and child welfare organizations, many children are growing up in foster homes. Human love must move us to approve and enrich these foster families; childhood is too brief and important to be knowingly allowed disapproved or impoverished experience. This paper describes the foster situation: families, children, and the involved professionals. It then presents a teachable developmental theory weaved from threads of numerous known theories, and describes a process whereby "interminable" foster experience was used therapeutically for a group of handicapped homeless children.

Child↗
PubMed1978

The effects of blood loss on the performance of physical exercise.

Seven male subjects were studied before and up to 53 days after the loss of 11 of blood. The resting hematocrit fell from 44.0 to 38.7% and returned to control level after 3 weeks. Maximal oxygen uptake decreased from 4.00 1/min to 3.54 1/min and returned to the initial level within 2 weeks. Submaximal oxygen uptake, pulmonary ventilation, maximal heart rate and blood lactate were not found to change significantly. Submaximal heart rate was increased from 125 beats . min-1 to about 135 beats . min-1 and remained elevated for 3 weeks, whereas blood lactate was increased only in the first week. Maximal work time decreased from 5.1 min to 3.8 min and remained low for the first 2 weeks, but rose thereafter above the starting level. Comparison with a control study suggested that there is some training effect, which, when allowed for, indicates that maximal work time returns to starting values at the same time as does the maximal oxygen uptake. It is concluded that the drop in Hct, maximal oxygen uptake and work capacity, found after the loss of 11 of blood, are related to each other both in magnitude and duration.

Adult↗