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11.
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Suramin was used to analyze the growth-effects of blockade of iron uptake on two established human cell lines, U-937 (monocytoid) and K-562 (erythroleukemic). Suramin suppressed cell surface transferrin (Tf) binding and uptake of iron via inhibition of receptor-mediated endocytosis (RME). As a result, both lines accumulated in the S-phase. DNA synthesis and cell division were inhibited in the suramin-treated U-937, but not in K-562. Iron, supplied by a route alternative to Tf-to suramin-suppressed U-937 cells, reinitiated DNA synthesis and cell division, although at a lower level than in control cells. Multiple effects on iron-dependent enzymes and an inhibition of binding of undefined growth factors necessary for the transition through the cell cycle are suggested to be mechanisms by which suramin affects the U-937 cells. The results imply that clinically observed side effects of suramin may be caused by interference with cellular iron metabolism.  相似文献   
13.
A review of hip radiographs of patients with severe hemophilia showed Legg-Calvé-Perthes disease in four of 63 patients examined before the era of specific treatment. In another series of 44 patients receiving prophylactic treatment, there was no evidence of Legg-Calvé-Perthes disease. A case report of a boy with severe hemophilia with hip joint bleeding that caused joint capsule distention and greatly increased intracapsular pressure is presented. Based on our findings, and previously published results, we suggest that Legg-Calvé-Perthes disease in hemophilia is caused by increased intracapsular pressure secondary to hemarthrosis.  相似文献   
14.
Blood cell trauma and postoperative bleeding were studied in 96 patients following coronary artery bypass grafting, with bubble oxygenator used in 47 cases and membrane oxygenator in 49. The haemocompatibility of membrane oxygenators was superior to that of the bubble type, as reflected by less haemolysis, better preservation of platelet function, less release of betathromboglobulin and less degranulation of neutrophil granulocytes. Coronary suction contributed to haemolysis, but did not affect platelet or granulocyte function. Fibrinolysis, postoperative blood loss and need for blood transfusion did not differ between the bubble and membrane oxygenator groups.  相似文献   
15.
We studied 362 fractures of the femur that had occurred during the years 1950-57 and 1973-83, and 849 fractures of the tibia that occurred during the the years 1950-55 and 1980-83. There was an increase in age-specific incidence over aged 60 years. The risk of low-energy femoral shaft fractures also had increased in elderly women. Both fracture types shifted their age- and sex-specific incidence in the direction of a fragility pattern. There was no increase in the incidence of tibial shaft fractures. Fracture type, site, and degree of displacement of the tibial fractures remained unchanged during the 30 years, i.e, they were predominantly distal, longitudinal fractures with moderate displacement.  相似文献   
16.
Cancer incidence of workers in the Swedish petroleum industry.   总被引:3,自引:2,他引:1       下载免费PDF全文
OBJECTIVES: To estimate the risk of cancer due to occupational exposure to petroleum products in the Swedish transport and refinery industries. METHODS: In a retrospective cohort study the cancer incidence in 4128 men and 191 women, who had worked for at least one year in the petroleum industry, was compared with the incidence in the general population. The job titles and employment times for each person were found in personal files in the industries. The men had on average worked in jobs exposed to petroleum for 11.6 years at the end of the observation period. The cases of cancer were identified by record linkage with the Swedish cancer register. RESULTS: In total there were 146 cases of cancer v 157.6 expected (standardised mortality ratio (SMR) 0.93 90% confidence interval (90% CI) 0.80 to 1.1). Operators at refineries had an increased risk of leukaemia (6 cases v 1.7 expected, 90% CI of relative risk (RR) 1.5 to 7.0). Five of the six cases had started to work at the refineries in the 1950s or later. No other significantly increased risk of cancer was found. Distribution workers had a decreased incidence of lung cancer (no cases, 90% CI of RR 0 to 0.4). CONCLUSIONS: Operators at Swedish refineries had an increased risk of leukaemia. A possible cause is exposure to benzene. There was no increased risk of leukaemia in distribution workers. Distribution workers had a decreased risk of lung cancer.  相似文献   
17.
Digital movment analysis (DMA) is a new instrumental approach to assessing oral tardive dyskinesia (TD) by means of digital image processing of a video signal, tracking five paper dots placed around the patient's mouth. A total of 40 schizophrenic patients, 30 with and 10 without TD, were examined twice (with a 3-month interval) with this new device. The patients were further examined with two TD rating scales: the St. Hans Rating Scale for extrapyramidal syndromes (SHRS) and the Abnormal Involuntary Movement Scale (AIMS).The schizophrenic patients accepted the instrumental assessment without any anxiety or resistance. The internal relibility of the apparatus was high, with correlation coefficients of 0.80–0.99. The DMA TD values correlated with the SHRS and AIMS scores with correlation coefficients of 0.48–0.73 indicating an acceptable, although not strong, concurrent validity. Fluctuations occurred from the first to the second examination independent of medication. For these fluctuations no correlation was found between DMA values and rating scores. Finally, the DMA device was able to detect perioral tremor as a sign of parkinsonism.It has been concluded that DMA is a useful supplement to classical TD rating, although further validity evaluation is warranted.  相似文献   
18.
19.
In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad, oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI, i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI shows most of the epidemiological characteristics of a sexually transmitted disease.  相似文献   
20.
Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.  相似文献   
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