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Present estimates of the quantitative relations between exposure to mixed respirable coalmine dust and risk of developing coalworkes' simple pneumoconiosis are based on studies of working miners. These studies did not include men who had been miners but had left the coal industry, and it was not known whether the estimates of risk were also appropriate for these men. The results are reported of a study in which the dust/disease relations in men who have been miners but have left the industry have been compared with those in men who have remained in it. A sample of 17738 men who were first examined when working in 24 British collieries in the 1950s has been followed up about 22 years later. It was possible to examine 61% of the survivors, 44% of the original sample. Simple pneumoconiosis was more frequent among men (particularly older men) who had left the industry than among those who had stayed in it. A detailed analysis did not show any systematic or statistically significant difference between men who stayed and men who left in the quantitative relations between dust exposure and simple pneumoconiosis. Present estimates of risk of simple pneumoconiosis in relation to exposure to mixed respirable dust in working miners adequately describe the relation found in men who have been miners but have left the industry.  相似文献   
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The anterolateral thigh (ALT) flap has achieved popularity recently for free-flap reconstruction of intraoral defects following excision of squamous cell carcinoma. We have assessed the feasibility of the ALT flap as a free flap for oral lining and the potential use of the thinned ALT flap in a one-stage reconstruction. We used the ALT flap to reconstruct the oral cavity in 18 consecutive patients between December 2000 and December 2001 following intraoral resection of squamous cell carcinoma. Twelve patients underwent reconstruction using a standard ALT flap, four patients received a thinned ALT flap in a one-stage procedure, one patient received a standard ALT flap in combination with a fibula flap and one patient received a combination of a standard ALT flap and vascularised iliac bone. There were no complications in any of the 14 cases in which a standard ALT flap was used. Two of these flaps were thinned subsequently as secondary procedures. Of the four thinned ALT flaps, one flap failed completely and two flaps experienced partial necrosis. In all but one case the donor site was closed directly with minimal donor-site morbidity. The ALT flap is a versatile flap that can be used in combination with other flaps for more complex defects with minimal donor-site morbidity and is a useful alternative in the armamentarium of the head and neck surgeon. Thinning of the flap is best performed as a secondary procedure, should it be required.  相似文献   
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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing.  相似文献   
5.
Catheter tip position in central vein thrombosis   总被引:2,自引:0,他引:2  
Clinical central venous thrombosis (CVT) was found to be associated with a catheter tip position in the superior vena cava (SVC), but not in the right atrium (RA), in patients receiving a standard parenteral nutrition regime in which dextrose was the sole energy source. CVT was rare with standard lipid containing three in one mixes, even when the catheter tip lay in the SVC. The reasons for this are discussed and the complications associated with catheter tip position are reviewed.  相似文献   
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BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
9.
Follistatin and activin A production by the male reproductive tract   总被引:1,自引:0,他引:1  
Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.   相似文献   
10.
To make a preliminary assessment of whether upper limb soft tissue disorders might be associated with activities at work, we have conducted a case-control study of subjects attending orthopedic clinics in three cities. All subjects between the ages of 16 and 65 years, in whom defined soft tissue conditions of the upper limb were diagnosed by the participating orthopedic surgeons, were invited to take part. Controls were subjects attending the same clinics within the same age range whose clinical diagnosis did not include disease of the upper limb, cervical or thoracic spine. Information concerning repetitive movements of the upper limbs at work was elicited by questionnaire. Five hundred eighty cases and 996 controls were studied, representing 96% and 93%, respectively, of those invited to participate. The diagnoses of the cases included soft tissue conditions affecting the shoulder, elbow, forearm, wrist, thumb, hand, and fingers. The diagnoses of the controls included traumatic, degenerative, and inflammatory conditions, mostly of the legs and lower back. Women predominated among the cases (70%) and men among the controls (56%). Of 221 female cases with injury to the wrist and forearm, 32 were cleaner/domestics (14.5%) compared to 35 of 439 controls (8%), a difference statistically significant at the 2 1/2% level. Other jobs significantly overrepresented (5% level) among female cases with injuries at various anatomical sites included hairdressers, secretary/temps, assembly line workers, and machine operators (type unspecified). Among male cases, electricians were significantly overrepresented (5% level). Jobs for which there was a suggestion (p < 0.1) of overrepresentation among cases included butchers and teacher/ lecturers (both males only) and the combined job groups (chosen a priori for analysis) of keyboard operators, machine operators, and music teachers (all three jobs, females only).  相似文献   
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