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31.
In the article ‘Supervisory control for fault-tolerant scheduling of real-time multiprocessor systems with aperiodic tasks’, Park and Cho presented a systematic way of computing a largest fault-tolerant and schedulable language that provides information on whether the scheduler (i.e., supervisor) should accept or reject a newly arrived aperiodic task. The computation of such a language is mainly dependent on the task execution model presented in their paper. However, the task execution model is unable to capture the situation when the fault of a processor occurs even before the task has arrived. Consequently, a task execution model that does not capture this fact may possibly be assigned for execution on a faulty processor. This problem has been illustrated with an appropriate example. Then, the task execution model of Park and Cho has been modified to strengthen the requirement that none of the tasks are assigned for execution on a faulty processor.  相似文献   
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OBJECTIVES: To determine whether biopsy-detectable transition zone tumors are more common in black than in white men with suspected Stage T1c and T2 prostate cancer. METHODS: We performed a prospective study of transition zone prostate biopsy (TZ biopsy) in 1 78 black and 261 white men who had not undergone previous prostate biopsy and in 61 black and 65 white men who had undergone one benign sextant peripheral zone prostate biopsy (PZ biopsy). RESULTS: The mean age of the 239 black and 326 white study patients was 68.6+/-7.4 and 67.2+/-7.2 years, respectively (P = 0.02), the mean prostate-specific antigen (PSA) was 8.4+/-7.4 and 6.4+/-5.4 ng/mL, respectively (P = 0.003), and the mean PSA density was 0.20+/-0.23 and 0.16+/-0.16 ng/mL/mL, respectively (P = 0.006). Overall, cancer was diagnosed by TZ biopsy only in 7 black men (3%) and in no white men (0%) (P = 0.003). However, cancer detection with a TZ biopsy only was not significantly different in the black and white men when controlled for age, PSA, or PSA density (P>0.90). A TZ biopsy only detected cancer in 1% of patients who had not undergone prior PZ biopsy and in 2% of patients who had undergone prior PZ biopsy. Of the seven cancers detected with TZ biopsy, six (86%) had a Gleason score of 2 to 6. CONCLUSIONS: Prostate cancer detection with a TZ biopsy only is not common and when controlled for confounding variables is the same in black and white men. The preferential use of TZ biopsies in black men is not warranted, and the low diagnostic yield argues against routine use of the biopsy technique in men of either race.  相似文献   
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Recent studies indicate beneficial effects of androgen depletion in male mice, before trauma-hemorrhage on cell-mediated immunity following soft-tissue trauma and hemorrhagic shock. Nonetheless, it remains unknown whether androgen receptor blockade following the insult has any salutary effects. To study this, male C3H/HeN mice were either sham-operated or subjected to soft-tissue trauma (i.e., 2.5 cm midline laparotomy) followed by hemorrhagic shock (blood pressure 35 +/- 5 mmHg for 90 min) and then adequately resuscitated (shed blood and lactated Ringer's). Immediately after the completion of resuscitation, as well as 24 and 48 h thereafter, the animals received either vehicle, 10 mg/kg body weight (BW) flutamide or 25 mg/kg BW flutamide subcutaneously. At 72 h after resuscitation, all animals were killed. The spleens and peritoneal macrophages (M phi) were then harvested and cultures established to determine IL-2 and IL-3 release, splenocyte proliferative capacity, as well as splenic and peritoneal M phi IL-1 release. Moreover, plasma testosterone and corticosterone levels were measured. Our results indicate that trauma-hemorrhage resulted in significant depression of splenocyte and M phi functions in vehicle-treated and animals receiving 10 mg/kg BW flutamide. Treatment with 25 mg/kg BW flutamide following trauma-hemorrhage, however, resulted in levels of cytokine release which were comparable with those found in sham-operated animals. No significant alterations in plasma corticosterone and testosterone levels were observed in any of the experimental groups. These findings indicate that short-term therapy of males with the androgen receptor blocker, flutamide at 25 mg/kg BW, following trauma-hemorrhage has protective effects on immune functions. This protective effect is dose dependent, since 10 mg/kg BW flutamide did not produce significant salutary effects. Thus, flutamide represents a novel and safe agent for improving the depressed functions in male trauma patients suffering severe blood loss.  相似文献   
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Diuron in both, acute (340 and 170 mg/kg body wt) and chronic (3400 ppm) doses induced dominant lethal mutations in male Swiss albino mice. The results suggest that diuron is mutagenic in dominant lethal test system.  相似文献   
36.
OBJECTIVES: To determine concentrations of chondroitin sulphate (CS) and keratan sulphate (KS) epitopes, glycosaminoglycans (GAGs) and hyaluronan (HA) in knee synovial fluid (SF) from normal subjects and patients with osteoarthritis (OA) or rheumatoid arthritis (RA), to test whether these variables may be used as markers of the OA process. METHODS: OA was subdivided into large joint OA (LJOA), nodal generalised OA (NGOA), and OA with calcium pyrophosphate crystal deposition (CPA). Clinical assessment of inflammation (0-6) was undertaken on OA and RA knees. Knee SF was examined by enzyme linked immunosorbent assay for: CS epitopes, using monoclonal antibodies 3-B-3 and 7-D-4; KS epitope using monoclonal antibody 5-D-4; and HA, using biotinylated HA binding region of cartilage proteoglycan. Total sulphated GAGs were measured by dye binding with 1:9 dimethylmethylene blue. RESULTS: Increased SF 3-B-3 concentrations and 3-B-3/GAG ratio were found in OA, compared with RA or normal knees, with higher 3-B-3 and 3-B-3/GAG in LJOA and NGOA than in CPA. SF 7-D-4 and 7-D-4/GAG were reduced in RA, compared with normal and OA; SF 5-D-4 was reduced in OA compared with normal. GAG and HA concentrations were decreased in both OA and RA. No correlations with radiographic scores were observed, but SF 7-D-4 was lower in 'inflamed' compared with 'non-inflamed' RA and OA knees. In patients with bilateral samples there were strong correlations between right and left knees for all SF variables. CONCLUSIONS: Changed concentrations of SF CS and KS can be detected in OA with a profile that differs from that seen in RA. Clinical subgrouping and local joint inflammation may influence these measures, supporting different pathogenesis within OA subgroups and requirement for careful patient characterisation in SF studies.  相似文献   
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Air pollution control (APC) residues produced from cleaning gas emissions at energy from waste (EfW) plants processing municipal solid waste are a problematic hazardous waste. In this research they have been treated using DC plasma technology and this produces an inert glass. Glass-ceramic tiles were prepared by powder pressing and sintering fritted APC residue-derived glass. Tile samples prepared with high levels of plasma treated APC residue glass had comparable physical properties to commercially available ceramics such as porcelain and monoporosa, with high bulk density (2.4 g/cm3), low water absorption (<6%) and high flexural strength (∼60 MPa).  相似文献   
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A combined retrospective and prospective study of 129 beta-thalassaemia major patients seen between 1965 and 1995 in Sabah Hospital, Kuwait has been carried out. The age range at diagnosis was 2 to 84 months, median 9 months. In approximately 80 per cent, the patients were outcomes of first- or second-cousin marriages. Nine (7 per cent) of the patients were HBsAg positive, while 42 (33 per cent) were hepatitis C seropositive. Eleven (9 per cent) patients had had bone marrow transplantation (BMT). There was no BMT-related mortality, but there were three graft rejections and two cases of chronic graft-versus-host disease (GVHD).  相似文献   
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