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21.
Totally, 185 patients, operated on for a fresh hip fracture, were randomly allocated to either methicillin antibiotic prophylaxis or no prophylaxis and followed for 1 month. Two superficial wound infections were recorded in the prophylaxis group and one in the control group. Prophylactic use of antibiotics in surgery for hip fractures seems unnecessary provided strict aseptic routines in the operating room are followed.  相似文献   
22.
Among 600 traumatic spinal cord injured (SCI) patients admitted during a 20 year period, 67 had a tracheostomy performed (11.2%). Of these 67 patients 46 had a cervical SCI. A concomitant thoracic trauma had occurred significantly more often in the group with thoracic or lumbar SCI than in those with a cervical SCI. The period from injury to tracheostomy was 0-48 days (median 4.4 days), and from tracheostomy to decannulation 3-167 days (median 31 days). At follow up 20 (30%) had died, primarily because of respiratory problems. Of the remaining 47 patients, 43 (91%) responded to a follow up questionnaire 3.5-21.7 years (median 10.4 years) after the injury. In the follow up 53% reported never to have had any inconvenience or trouble related to the tracheostomy. The major inconvenience among the others had been of cosmetic origin (28%), and 3 had had a surgical revision for this reason. At the time of follow up 9 patients (21%) still had certain complaints, primarily described as difficulty in swallowing. Minitracheostomy might in the future reduce the number of these complications.  相似文献   
23.
Patients with cystic fibrosis commonly acquire chronic pulmonary infection with alginate-producing Pseudomonas aeruginosa. The infection remains localized at the mucosal surfaces of the airways. Using enzyme-linked immunosorbent assays immunoglobulin concentrations and titers of specific antibodies to purified P. aeruginosa alginate and to P. aeruginosa sonicated antigens were measured in tears, saliva, sputum and serum. CF patients had significantly higher concentrations of IgG, IgA and SIgA in serum and saliva than controls. They also had significantly higher levels of specific antibodies to alginate and sonicated antigen in secretions and serum. Local production of IgA, IgG and IgM antibodies to P. aeruginosa was demonstrated. Only a minor proportion of specific IgA antibodies were present as secretory IgA in tears, saliva and sputum. The ratio of alginate-specific SIgA to specific monomeric IgA in sputum was significantly lower than the similar ratio in saliva, whereas the same ratio for specific P. aeruginosa sonicate antigens was found in saliva and sputum.  相似文献   
24.
The isolated spontaneously beating heart was used for comparing the effects of hypoxia and positive inotropic drugs on myocardial ultrastructure. Hypoxia gives a significant decrease in the volume fractions of mitochondrial cristae relative to the total mitochondrial volume (Vvmcristae) and a significant increase in the volume fraction of mitochondrial matrix relative to the total mitochondrial volume (Vvmmatrix), but changes in volume fractions of mitochondria (Vvmitochondria) and myofibrils (Vvmyofibrils) were absent. Significant changes in ultrastructure in hearts treated with dopamine (0.6 microM), dobutamine (90 nM), G-strofanthin (0.25 microM), xamoterol (32 nM) and isoprenaline (0.15 microM or 15 nM) were absent. Furthermore, myocardial effects in the isolated rabbit heart without exposure to any treatment showed a significantly decrease in oxygen consumption after 90 min. and a significant decrease in frequency of contractions after 120 min. perfusion time, but no change in contractility was seen. We conclude that this experimental model is useful in studies of positive inotropic drugs.  相似文献   
25.
26.
Renal tubular sodium and water handling determined by the lithium clearance technique, plasma concentrations of atrial natriuretic peptide (ANP), angiotensin II, aldosterone, arginine vasopressin (AVP), and urinary excretion of prostaglandin E2 (PGE2) were determined both during basal conditions and before and after intravenous sodium loading with a 2.5% sodium chloride solution in patients with polycystic kidney disease (PKD), ten with normal or slightly reduced kidney function (PKDN) and seven with moderately reduced kidney function (PKDR), and in 15 healthy controls. In PKDN tubular function was normal, whereas in PKDR both proximal and distal reabsorption of sodium and water were reduced. Angiotensin II and aldosterone were normal in both groups of patients. During basal conditions ANP was higher in PKDR than in PKDN. PGE2 was significantly higher in PKDR than in PKDN. For all patients significant correlations were found between GFR and both ANP (rho = -0.51, n = 17, P less than 0.05) and PGE2 (rho = -0.53, n = 17, P less than 0.05). It is concluded that renal sodium handling is normal in the early stages of PKD. With deterioration of kidney function both proximal and distal tubular reabsorption of sodium is reduced and the accompanying changes in ANP and PGE2 may be compensatory phenomena counteracting declining glomerular filtration rate.  相似文献   
27.
In this prospective, randomized study the clinical response and toxicity of megestrol acetate (MA) and aminoglutethimide (AG) as second-line treatment in patients with metastatic breast cancer was compared. 176 patients were included, and 150 received treatment greater than 8 weeks and are evaluable for treatment response. The two groups did not differ with regard to prognostic factors. Response rate for the AG and MA groups were 34% and 31% respectively, with duration of response of 13.1 and 13.0 months. Stable disease was obtained in 33% and 35% respectively. No difference was observed in survival. Side effects occurred more frequently in the AG group (42%) than in the MA group (18%).  相似文献   
28.
Increased osmotic pressure has been reported to cause non-cytotoxic histamine release (HR) from human basophils, as well as a potentation of HR induced by anti-IgE. In this study, the effects of hyperosmolar Na–K-acetate (300–600 mOsm/kg H2O) on HR was studied in washed human blood cells from newborns, adult volunteers and patients with severe atopic dermatitis. These three patient groups represesented 3 very distinct populations with respect to total plasma IgE content, medians were <0.2 IU/ml, 20.5 IU/ml and 2508 IU/ml, respectively. Increasing osmolarity to 500 mOsm/kg H2O caused little HR in the absence of other stimuli, whereas at 600 mOsm/kg H2O a significant increase in spontaneous HR was seen. The HR induced by anti-IgE and Concanavalin A, acting through the IgE-receptor, was increased approximately twofold at 500 mOsM/kg H2O. Responses were highly correlated to results at 300 mOsm/kg H2O. The use of 600 mOsm/kg H2O buffers caused a further increase in most, but not all blood samples. The potentiation of IgE-receptor-mediated HR when using hyperosmolar media was clearly independent of plasma IgE contents, and did not change the concentration-response to anti-IgE. In contrast, HR induced by the IgE-receptor-independent stimuli, Formyl-met-leu-phe and calcium ionophore A 23187, were not enhanced at all by incrased osmotic pressure. We conclude, that hyperosomolar media selectively enhance IgE-receptor-mediated HR. The use of hyperosmolar media may therefore be beneficial in a diagnostic application of washed blood HR assays use in allergy diagnosis.  相似文献   
29.
In contrast to previous studies, Parker et al. (Diabetes (1989) 38, 1123) have recently found that isolated rat adipocytes alone were unable to synthesize prostaglandins (PG) and that the PG measured in adipocyte suspensions were due to contaminating non-adipocyte cells. In the present study the capacity of adipocytes to produce PGE2 has further been explored. Preparations of isolated rat adipocytes were extensively washed in order to get rid of contaminating cells. The released PGE2 was measured by radioimmunoassay (RIA) after high-performance liquid chromatography (HPLC) separation. We found that after repetitive washing (up to 20 times) the isolated adipocytes were still able to synthesize PGE2 and this process was fully activatable by epinephrine, which indicates that pure adipocytes, themselves, are able to produce PGE2. However, addition of non-adipocyte material (from the adipose tissue) to 'pure' adipocytes (washed 10 times) enhanced the PGE2 synthesis significantly (P less than 0.001) as compared to 'pure' adipocytes alone. Thus, some kind of synergy exists between adipocytes and non-adipocyte cells in the adipose tissue in respect to PG formation. Some regulatory aspects of PG synthesis in 'pure' adipocytes were also investigated. Phospholipase A2 (2 U/ml) enhanced PGE2 synthesis significantly (119 +/- 21 to 658 +/- 85 pg/10(6) cells, P less than 0.001) without affecting lipolysis (glycerol release). The combined effect of epinephrine (5 microM) and phospholipase A2 (2 U/ml) on PGE2 formation was almost additive. Insulin inhibited the epinephrine-induced PG formation (P less than 0.01) but had no effects on the action induced by phospholipase A2.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.

Background  

Despite considerable knowledge about musculoskeletal disorders (MSD) and physical, psychosocial and individual risk factors there is limited knowledge about physical activity as a factor in preventing MSD. In addition, studies of physical activity are often limited to either leisure activity or physical activity at work. Studies among military personnel on the association between physical activity at work and at leisure and MSD are lacking. This study was conducted to find the prevalence of MSD among personnel in the Royal Norwegian Navy and to assess the association between physical activity at work and at leisure and MSD.  相似文献   
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