Biomonitoring of genotoxic exposure of aluminium plant workers.

Humans are environmentally and occupationally exposed to polycyclic aromatic hydrocarbons (PAH). PAH's are a class of tumorigenic compounds which act through metabolic transformation to chemically reactive forms, epoxides, which covalently bind to DNA forming DNA adducts. To evaluate the genotoxic effects of PAH's, air and urine samples were analyzed for PAH. Blood samples were analyzed for benzo(a)pyrene-diol-epoxide-DNA (BPDE-DNA) adducts. New methods for analyzing DNA adducts in lymphocytes have been used to study the genotoxic effects of human exposure to carcinogens. BPDE-DNA adducts in lymphocytes have been used as internal dosimeters of exposure to PAH's and several studies have been conducted. We measured BPDE-DNA adducts in aluminium plant workers with immuno-assay and physico-chemical methods. PAH-DNA adducts were detectable to a lesser extent in subjects working in an aluminium plant compared to subjects working in a coke oven plant.     

Risk factors for diabetic retinopathy in children and adolescents with type I diabetes mellitus

Based on repeated fluoroangiographic examinations in a group of 28 children with type I diabetes mellitus the authors observed progressing diabetic retinal changes. At the end of the three-year observation period they found progress in 32% of the children. They investigated influence of risk factors such as age, duration of the basic disease, its metabolic compensation, sex and HLA typing on the development of diabetic retinopathy.     

Transient protein S deficiency with deep venous thrombosis during Salmonella typhimurium infection

A patient with deep venous thrombosis and low protein S activity during the course of Salmonella typhimurium infection is presented. Although protein S deficiency has been reported in patients with disseminated intravascular coagulation, it was not present in this patient and his protein S activity was normal after the findings of infection and deep venous thrombosis disappeared.     

Effects of nail rigidity on fracture healing

The present study was undertaken to assess the effects of the rigidity of nails on the healing of fractures as evaluated by mechanical strength and rate of bone mineralisation. Ten rats supplied biomechanical data at the start of the experiment and another 100 rats were randomly assigned to 5 groups. In 20 rats no intervention was performed, and they served as a reference group of normal values. Thus, 80 rats underwent a standardised partial osteotomy in the left femur diaphysis prior to manual fracture, reaming and intramedullary nailing. One group received rigid steel nails (group 1) and another, cannulated steel nails (group 2). Group 3 received semi-rigid titanium nails and group 4, soft polyethylene nails. Ten rats in each group were evaluated at 6 and 12 weeks after fracture, and radiographs and callus diameter measurements were performed. Dual-energy X-ray absorptiometry (DEXA) of the bones was performed, and the degree of mineralisation in the callus segment, distal diaphysis and total femur was calculated by the scanner. Subsequently, the bones were tested mechanically by a three-point bending test in a Mini Bionix (MTS) testing system. Radiographs revealed clearly visible fractures at 6 weeks in the intervention groups. At 12 weeks there were no signs of bridging callus in group 4, while the other groups presented scarcely visible osteotomies. The callus area in group 4 was significantly larger at both 6 and 12 weeks than in groups 1–3. In these groups there was a significant decrease in callus area between 6 and 12 weeks. Both maximum bending load, bending rigidity and fracture energy increased significantly in groups 1–3 between 6 and 12 weeks, while bending load and fracture energy increased in group 4. At 6 weeks no significant differences were detected between groups 1–3 in mechanical strength. Group 4 had a significantly reduced maximum bending load and fracture energy at 6 and 12 weeks as well as bending rigidity at 12 weeks. At 12 weeks group 3 had a significantly increased maximum bending load and fracture energy compared with groups 1 and 2. Bone mineral count (BMC) in the callus region in group 4 was significantly reduced at both 6 and 12 weeks. BMC in the callus showed no significant differences between groups 1–3, either at 6 or at 12 weeks. BMC in the distal diaphysis was significantly reduced in groups 1 and 4 compared with group 2 at 12 weeks. Bone mineral density (BMD) in the callus region revealed no significant differences between groups 1–3 at 6 weeks, while at 12 weeks BMD was higher in group 3 than in group 1. BMD in the callus region and total femur in group 4 was significantly reduced at 6 weeks. This study demonstrates that diaphyseal fractures treated with titanium nails with a bending rigidity similar to the intact femur have a higher maximum bending load and fracture energy at 12 weeks than both rigidly or softly nailed fractures. BMD in the callus region was also highest after titanium nailing at 12 weeks. BMD in the distal diaphysis and total femur indicates that the degree of stiffness of the nails have little influence on total bone mineralisation at 12 weeks.     

适应社会主义市场经济 发展妇幼保健机构

本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。     

Outpatient anterior chamber lens implantation

100 outpatient and 143 inpatient intracapsular cataract extractions with anterior chamber lens implantation were examined 6 months post-operatively. 74 (74%) in the former and 107 (75%) in the latter achieved visual acuity greater than or equal to 0.5. Excluding non-surgical pathology, 93% in the outpatient group and 98% in the inpatient group had a visual acuity greater than or equal to 0.5 (P = 0.12). There were no significant differences in post-operative complications except for the incidence of cystoid macular edema. Six (6%) of the outpatient and 1 (0.7%) of the inpatient procedures had cystoid macular edema that resulted in a visual acuity below 0.5 (P = 0.02).