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61.
Summary Currently there are no limitations on age of employment on private forestries in Japan. Hence, it was hypothesized that in these kind of enterprises, elderly chain saw operators, or those with long-term exposure, might be at higher risk of developing hand-arm vibration syndrome (HAVS). We consequently investigated the prevalence of HAVS in 447 chain saw workers on private forestries in Gifu Prefecture, Japan, with particular reference to age and exposure period. Of this population, 43 (9.6%) had signs and symptoms of vibration-induced white finger (VWF), and among these workers the severity of finger blanching was significantly correlated (P < 0.01) with the exposure period. Classification of all subjects by exposure period showed that workers with 30 years' exposure had higher prevalences of VWF (20.9%) and numbness of the hands (25.4%) compared to other groups. Significant differences (P < 0.01) were found between the functional capacities of workers with VWF and those of control subjects. We concluded that (a) the elderly chain saw operators and those with longer exposure should be moved to other jobs with a lower or no risk of exposure to vibration, and (b) the results of screening tests, even without cold water immersion (which we did not employ, in order to protect workers' hands), could be helpful for the identification of workers with VWF.  相似文献   
62.
In clinical settings, no method has been established to examine the fatigue of a latissimus dorsi muscle (LDM) preconditioned for cardiomyoplasty. We examined the feasibility of measuring muscle stiffness (tactile stiffness) to evaluate muscle fatigue in situ using our tactile sensor. We stimulated canine LDM with burst pacing and monitored both stiffness and tension to determine their relationship. In both dissected LDM and LDM in situ, the decrements of these parameters during burst pacing were compared between preconditioned and unconditioned LDM. In measurement in situ, the sensor probe was placed on the LDM through a small incision. Strong statistical correlation was shown between stiffness and tension (r = 0.935). In decrements of stiffness in situ, there were statistically significant differences between preconditioned and unconditioned LDM. Our tactile sensor system can provide an efficient method for evaluating fatigue of muscles in situ without measuring muscle tension.  相似文献   
63.
A 5 year follow-up study was conducted to investigate the relationships between %changes in serum lipids and blood pressure and corresponding changes in exercise habits in the middle-aged. The subjects were 152 males and 169 females who received a health check-up at 30-years-old during the period between 1990-1992 and then at 35-years-old during the period between 1995-1997. The results are as follows: 1. In multiple regression analysis, % delta toriglyceroid (TG) and % delta AI(atherogenic index) ratio were associated significantly with changes in exercise habits in males (P < 0.05) and % delta high density lipoprotein cholesterol (HDLC) was associated with changes in exercise habits in females (P < 0.05). % delta TG and % delta HDLC were affected by changes in exercise habits adjusted for BMI, smoking, and drinking. But changes in TC and blood pressure were not affected by changes in exercise habits. 2. In males, % delta TG was significantly lower in those subjects who started their exercise habit than in the no exercise group and than in those within the ceased exercise group who ceased their exercise during the study period (P < 0.05). % delta AI was significantly lower in the started exercise group than in the no exercise group. Also, the continued exercise group had a significantly (P < 0.05) lower % delta AI as compared to the ceased exercise group. In females, % delta TG was significantly lower in the started exercise group than in the no exercise group (P < 0.05). % delta HDLC was higher significantly in the continued exercise group than in the ceased exercise group (P < 0.05). From the results obtained, it is recommended that the no exercise subjects should have exercise more than once time per week and those with more than 1 time per week maintain their exercise habits.  相似文献   
64.
A 5-fluorouracil (5-FU)-resistant subline of human colon cancer HT-29 cells was developed by repeated 1-h exposure in vitro to 5-FU. This subline (HT-29/5-FU/S) had 8-fold resistance to 5-FU in a 1-h exposure assay. However, it had rather increased sensitivity to 5-FU when assayed after a continuous 96-h exposure to it. Significantly less 5-fluorouridine-5'-triphosphate was produced in the resistant cells, leading to a lower level of 5-FU incorporation into the cellular RNA. The reduced activity of orotate phosphoribosyltransferase might explain these results. In contrast, the HT-29/5-FU/S cells were more sensitive to the inhibition of in situ thymidylate synthase (TS) by 5-FU than were the parent cells. The lower in situ TS activity may have made HT-29/5-FU/S cells more sensitive to TS inhibition by 5-FU as compared with the parent cells. The fact that HT-29/5-FU/S was more resistant to short-term 5-FU exposure but more sensitive to long-term exposure than the parent line confirmed the existence of different modes of action of 5-FU, depending on the exposure time.  相似文献   
65.
We describe the technical benefits of the dual-access technique for venous stenting in high-grade stenosis. Stents were implanted successfully with this technique in all patients, although the preceding transfemoral interventions had failed. The dual-access technique is useful to facilitate the intervention when the stenoses are too severe to place the stent through just a single access point. Received: 21 October 1998; Revised: 23 February 1999; Accepted: 3 May 1999  相似文献   
66.
Life‐threatening cardiac events may be misdiagnosed as acute aortic dissection because of notable symptom mimicry. We report the case of a 72‐year‐old male patient with presentations presumed to be of aortic origin. However, surgery revealed posterior free‐wall perforation in the left ventricle caused by the occlusion of an obtuse marginal branch.  相似文献   
67.
Dendritic cell leukemia (DCL) or hematodermic tumor is an uncommon subtype of acute leukemia. In contrast to adult cases, children tend to have a less aggressive course. The diagnosis of DCL should be considered when its characteristic morphologic features are present and leukemic cells co‐express CD4 and CD56. Cases of DCL among pediatric patients have been reported to respond to therapeutic regimens for acute lymphoblastic leukemia, but details regarding the specifics of therapy are lacking. Pediatr Blood Cancer 2013; 60: E38–E41. © 2013 Wiley Periodicals, Inc.  相似文献   
68.
Glucose is the most important source of energy and homeostasis. Recent investigations are clarifying that glucose metabolism might be altered in rheumatoid arthritis (RA), which would play a role in the inflammatory phenotype of rheumatoid synovial fibroblasts. It may also play a role in a variety of autoimmune diseases’ pathophysiology by modulating immune responses and modifying autoantigen expressions. The research into glucose and its metabolism could lead to a better understanding of how carbohydrates contribute to the occurrence and duration of RA and other autoimmune diseases.  相似文献   
69.
Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition which involves various organs. This is a very rare case of IgG4-related lung disease (IgG4-RLD) with the invasion into diaphragm. The patient was a 71-year-old man with a long-term exposure to asbestos who had a mass shadow in the left lower lung lobe, which was suspected to invade the left diaphragm on computed tomography (CT). Positron emission tomography (PET)/CT also presented an avid intake of fluorodeoxyglucose in the mass, which suspected lung cancer. Although bronchoscopic biopsy could not lead to the definite diagnosis, we performed left lower lobectomy combined with the resection of left diaphragm. The specimen showed the features of IgG4-RLD on pathology: the vein stenosis and fibrosis around the vein, the infiltration of IgG4-positive cells, and IgG cells to IgG4 cells ratio of 40%. Furthermore, there were inflammatory cells infiltrating to the diaphragm.  相似文献   
70.
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