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41.
42.
根据笔者在传染科病房工作中的体会,从六个方面针对传染科工作的特殊性和存在的共性分别阐述了传染科护士在工作中如何高标准、严要求自己,如何对病人做到到位的护理,旨在提高传染科病房的整体护理质量,从而把更多的实惠让利于患者。  相似文献   
43.
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.  相似文献   
44.
The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase.  相似文献   
45.
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.  相似文献   
46.
Nine publications are reviewed concerning blood pressure (BP) levels among Amerindian tribes of the Amazon Basin. The lifestyle of these lowland peoples includes most known protective factors against hypertension, and relative isolation from Western society. The latter, however, is rapidly changing. Sampling, data, and analysis problems make current blood pressure data difficult to interpret, and provide a questionable baseline from which to document pressure change during rapid culture change for these groups. Ethnographic and epidemiological perspectives are offered for future blood pressure and health studies among native Amazonians.  相似文献   
47.
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.  相似文献   
48.
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.  相似文献   
49.
Outpatient anterior chamber lens implantation   总被引:1,自引:0,他引:1  
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).  相似文献   
50.
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