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Bacterial response to formation and growth of sea ice was investigated during autumn in the northeastern Weddell Sea. Changes in standing stock, activity, and carbon production of bacteria were determined in successive stages of ice development. During initial ice formation, concentrations of bacterial cells, in the order of 1 x 10 to 3 x 10 liter, were not enhanced within the ice matrix. This suggests that physical enrichment of bacteria by ice crystals is not effective. Due to low concentrations of phytoplankton in the water column during freezing, incorporation of bacteria into newly formed ice via attachment to algal cells or aggregates was not recorded in this study. As soon as the ice had formed, the general metabolic activity of bacterial populations was strongly suppressed. Furthermore, the ratio of [H]leucine incorporation into proteins to [H]thymidine incorporation into DNA changed during ice growth. In thick pack ice, bacterial activity recovered and growth rates up to 0.6 day indicated actively dividing populations. However, biomass-specific utilization of organic compounds remained lower than in open water. Bacterial concentrations of up to 2.8 x 10 cells liter along with considerably enlarged cell volumes accumulated within thick pack ice, suggesting reduced mortality rates of bacteria within the small brine pores. In the course of ice development, bacterial carbon production increased from about 0.01 to 0.4 mug of C liter h. In thick ice, bacterial secondary production exceeded primary production of microalgae.

Metabolic activity of bacteria was investigated in open water, newly forming sea ice, and successive stages of pack ice in the Weddell Sea. Microautoradiography, using [(3)H]leucine as substrate, was compared with incorporation rates of [(3)H]leucine into proteins. Relation of [(3)H]leucine incorporation to the biomass of active bacteria provides information about changes of specific metabolic activity of cells. During a phytoplankton bloom in an ice-free, stratified water column, total numbers of bacteria in the euphotic zone averaged 2.3 × 10(5) ml(-1), but only about 13% showed activity via leucine uptake. Growth rate of the active bacteria was estimated as 0.3-0.4 days(-1). Total cell concentration of bacteria in 400 m depth was 6.6 × 10(4) ml(-1). Nearly 50% of these cells were active, although biomass production and specific growth rate were only about one-tenth that of the surface populations. When sea ice was forming in high concentrations of phytoplankton, bacterial biomass in the newly formed ice was 49.1 ng C ml(-1), exceeding that in open water by about one order of magnitude. Attachment of large bacteria to algal cells seems to cause their enrichment in the new ice, since specific bacterial activity was reduced during ice formation, and enrichment of bacteria was not observed when ice formed at low algal concentration. During growth of pack ice, biomass of bacteria increased within the brine channel system. Specific activity was still reduced at these later stages of ice development, and percentages of active cells were as low as 3-5%. In old, thick pack ice, bacterial activity was high and about 30% of cells were active. However, biomass-specific activity of bacteria remained significantly lower than that in open water. It is concluded that bacterial assemblages different to those of open water developed within the ice and were dominated by bacteria with lower average metabolic activity than those of ice-free water.

Osteonecrosis of the femoral head is one of many well documented side effects of long term steroid (glucocorticoid) use. Studies have reported on the skeletal effects of short term, high dose steroid therapy. This paper illustrates that short term (up to 6 weeks), high dose steroid therapy, utilized in neurotraumatology or central nervous system disease, can lead to necrosis of bone at multiple sites. This retrospective review of 6 patients supports the 18 previously reported cases: there were 5 male and one female patient, with a mean age of 32.2 years. The patients received an average dose of 5100 mg methylprednisolone for 23 days. The average interval between steroid administration and the onset of symptoms was 28 months. There was radiographic evidence of osteonecrosis of both femoral heads in all 6 patients. The female patient also had osteonecrosis of both humeral heads and both femoral condyles. Five of twelve hip joints were healed by intertrochanteric osteotomy and revascularization. One patient underwent total hip replacement. We were unable to find risk factors in these 6 patients which would make them susceptible to belated osteonecrosis of the femoral head. It is reasonable to conclude that there is a substantial risk of osteonecrosis in patients treated with high dose steroids even on a short term basis.

The authors conducted a retrospective study of the incidence of anorexia nervosa in the industrialized canton of Zurich, Switzerland, during three randomly selected sampling periods from 1956 to 1975. The data were derived from case histories from nearly all medical, pediatric, and psychiatric clinics in this region. The incidence of anorexia nervosa increased significantly, from .38/100,000 for 1956-1958 to .55/100,000 for 1963-1965 to 1.12/100,000 for 1973-1975. This increase was not due to the fact that nowadays anorectic patients are hospitalized earlier or that they are hospitalized for less severe illness.

From 1976 through 1984, 48 primary caesarean hysterectomies were performed in the Department of Obstetrics and Gynaecology of the Medical School of Hannover. The indications for the operation, the risk factors and the postoperative course were analysed and compared with a control group of patients with a Caesarean section. Caesarean hysterectomies had a higher incidence of excessive blood loss, blood transfusion and urinary tract injury, especially of the bladder. Based on this experience Caesarean hysterectomy should be performed if a valid indication is present. The operation cannot be recommended routinely for the purpose of sterilisation.

Reconstructive surgery of ligamentous injuries of the Knee Joint is often associated with a considerable impairment of its integrity and requires a high standard of surgical technique. The postoperative course, aiming towards normal function, is demanding and bound to biomechanical and biological principles. It therefore has to be built up gradually and lasts basically 12 months - with an individual variety. Up to the 6th postoperative week the healing process is in the foreground. During the second phase, up to the 12th week careful rehabilitation is aimed to improve muscle strength, increase weight bearing and optimize mobility. In the third phase, from the 12th week on, the patient regains full strength, range of motion as well as coordination, and an integrated sport rehabilitation is started.

A case of primary malignant fibrous histiocytoma (MFH) of the breast occurring two years after surgical excision and radiation therapy for a carcinoma of the left breast is reported. Fine needle aspiration was positive for malignant cells, consistent with a pleomorphic sarcoma. Cytologic examination revealed giant cells with marked pleomorphism. Some cells showed single large nuclei with cytoplasmic vacuoles while others revealed multinucleation with foamy cytoplasm, phagocytosed erythrocytes and cellular debris. These findings are considered useful in the cytologic diagnosis of the pleomorphic variant of MFH.