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51.
This article presents air and surface sampling data collected over the first two years since beryllium was introduced as a target material at the National Ignition Facility. Over this time, 101 experiments with beryllium-containing targets were executed. The data provides an assessment of current conditions in the facility and a baseline for future impacts as new, reduced regulatory limits for beryllium are being proposed by both the Occupational Safety and Health Administration and Department of Energy. This study also investigates how beryllium deposits onto exposed surfaces as a result of x-ray vaporization and the effectiveness of simple decontamination measures in reducing the amount of removable beryllium from a surface. Based on 1,961 surface wipe samples collected from entrant components (equipment directly exposed to target debris) and their surrounding work areas during routine reconfiguration activities, only one result was above the beryllium release limit of 0.2 µg/100 cm2 and 27 results were above the analytical reporting limit of 0.01 µg/100 cm2, for a beryllium detection rate of 1.4%. Surface wipe samples collected from the internal walls of the NIF target chamber, however, showed higher levels of beryllium, with beryllium detected on 73% and 87% of the samples during the first and second target chamber entries (performed annually), respectively, with 23% of the samples above the beryllium release limit during the second target chamber entry. The analysis of a target chamber wall panel exposed during the first 30 beryllium-containing experiments (cumulatively) indicated that 87% of the beryllium contamination remains fixed onto the surface after wet wiping the surface and 92% of the non-fixed contamination was removed by decontaminating the surface using a dry wipe followed by a wet wipe. Personal airborne exposures assessed during access to entrant components and during target chamber entry indicated that airborne beryllium was not present in workers' breathing zones. All the data thus far have shown that beryllium has been effectively managed to prevent exposures to workers during routine and non-routine work.  相似文献   
52.
BackgroundIt is new clinical interest higher serum amylase level with pancreatitis after pancreaticoduodenectomy (PD) correlates with postoperative pancreatic fistula (POPF). Nevertheless, its evidence and study were scarce. We aimed to investigate correlation of serum amylase level immediate after PD and POPF occurrence.MethodsOf 163 patients who underwent PD at between January 2009 and December 2019, retrospective analysis was conducted to identify risk factors including serum amylase level immediate after PD for POPF occurrence.ResultsOverall incidence of POPF (25/163) was 15.3%. The patients occurred a POPF had significantly higher level of serum amylase on POD0 compared to in whom without a POPF (414 vs 253, p < 0.001). In univariate analysis, ASA classification, post pancreatectomy acute pancreatitis (POAP, serum amylase on POD0 >285IU/L) and Fistula Risk Grade were correlated with POPF occurrence. In multivariable analysis, Fistula risk grade and POAP were significantly associated with developing POPF.ConclusionIn patients with higher serum amylase (>285IU/L) on POD0 with higher fistula risk grade, comprehensive management to achieve mitigation of POPF is important.  相似文献   
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Background  

Musculoskeletal complaints influence general health status, but the relative contribution of concurrent upper and lower extremity disabilities on patient perceptions of general health is unclear.  相似文献   
56.
Vecchini  F; Patrene  KD; Boggs  SS 《Blood》1993,81(6):1489-1496
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures.  相似文献   
57.
Enterohepatic recirculation (EHC) can greatly enhance plasma drug exposures and therapeutic effects. This study aimed to develop a population pharmacokinetic model that can simultaneously characterize the extent and time-course of EHC in three species using fimasartan, a novel angiotensin II receptor blocker, as a model drug. All fimasartan plasma concentration profiles in 32 rats (intravenous doses, 0.3–3 mg/kg; oral doses, 1–10 mg/kg), 34 dogs (intravenous doses, 0.3–1 mg/kg; oral doses, 1–10 mg/kg), and 42 healthy volunteers (single or multiple oral doses, 20–480 mg) were determined via liquid chromatography-tandem mass spectrometry (LC-MS/MS) and simultaneously modeled in S-ADAPT. The proposed model quantitatively characterized EHC in three species after oral and intravenous dosing. The median (range) fraction of drug undergoing recirculation was 76.3% (64.9–88.7%) in rats, 33.3% (24.0–45.9%) in dogs, and 65.6% (56.5–72.0%) in humans. In the presence compared with the absence of EHC, the area under the curve in plasma was predicted to be 4.22-fold (2.85–8.85) as high in rats, 1.50-fold (1.32–1.85) in dogs, and 2.91-fold (2.30–3.57) in humans. The modeled oral bioavailability in rats (median (range), 38.7% (20.0–59.8%)) and dogs (median, 7.13% to 15.4%, depending on the formulation) matched the non-compartmental estimates well. In humans, the predicted oral bioavailability was 25.1% (15.1–43.9%) under fasting and 18.2% (12.2–31.0%) under fed conditions. The allometrically scaled area under the curve predicted from rats was 420 ng ⋅ h/mL for 60 mg fimasartan compared with 424 ± 63 ng ⋅ h/mL observed in humans. The developed population pharmacokinetic model can be utilized to characterize the impact of EHC on plasma drug exposure in animals and humans.

Electronic supplementary material

The online version of this article (doi:10.1208/s12248-015-9764-2) contains supplementary material, which is available to authorized users.KEY WORDS: animal to human scaling, enterohepatic recirculation, fimasartan, population pharmacokinetics, S-ADAPT  相似文献   
58.
The purpose of this report was to provide information for patients receiving inpatient rehabilitation after stroke and to identify the possible factors influencing functional outcome after inpatient rehabilitation. Stroke patients (n = 5,212) who were discharged from the Departments of Rehabilitation Medicine (RM) of university hospitals and rehabilitation hospitals from 2007 through 2011 were participants. Prevalence, age, transfer time after onset, length of stay (LOS), functional status at admission and discharge were analyzed. In all stroke subjects, cerebral infarctions (67%) were more common than hemorrhages. Cerebral infarctions in the middle cerebral artery territory were most common, while the basal ganglia and cerebral cortex were the most common areas for hemorrhagic stroke. The LOS decreased from 45 to 28 days. Transfer time after onset decreased from 44 to 30 days. Shorter transfer time after onset was correlated with better discharge functional status and shorter LOS. Initial functional status was correlated with discharge functional status. In ischemic stroke subtypes, cerebellar and brainstem strokes predicted better outcomes, while strokes with more than one territory predicted poorer outcomes with more disabilities. In hemorrhagic stroke subtypes, initial and discharge functional status was the lowest for cortical hemorrhages and highest for brainstem hemorrhages. This report shows that LOS and transfer time after onset has been decreased over time and initial functional status and shorter transfer after onset are predictors of better functional outcome at discharge.  相似文献   
59.
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation.  相似文献   
60.
Outcome of Orthotopic Liver Transplantation in Patients with Hepatitis C   总被引:2,自引:0,他引:2  
Recurrence of chronic hepatitis C (HCV) after orthotopic liver transplantation (OLT) is universal. The published studies suggest that the short-term outcome is good in these patients, but the long-term prognosis remains unclear. The purpose of this study was to evaluate the outcome of patients with HCV undergoing OLT in a single center and to analyze the risk factors associated with poor outcome. In this retrospective study, we evaluated the outcome of 58 OLT patients with proven HCV who underwent OLT between February 1990 and April 1997 at our institution. The median follow-up time was 36.9 months. Recurrent posttransplant HCV hepatitis was confirmed by liver biochemistry, histology, and persistent HCV RNA in the serum. The patient and graft survival of patients with HCV was compared to that of 42 primary biliary cirrhosis (PBC) and 41 primary sclerosing cholangitis (PSC) patients transplanted during the same period. Following OLT, biochemical evidence of recurrent HCV hepatitis was absent in 46%. Forty percent of patients had recurrent HCV hepatitis and 14% had clinical evidence of recurrent HCV. Thirty-one patients were on cyclosporine, 22 patients on tacrolimus, and 5 patients had cyclosporine switched to tacrolimus or vice versa. The recurrence rate of HCV chronic hepatitis was similar in patients who had cyclosporine (35.5%) or tacrolimus (45.5%) based immunosuppression. Eleven patients (19%) died and five patients (8.6%) were retransplanted for chronic rejection (two), mismatch (one), or primary graft nonfunction (two). The cumulative patient survival rates of one, three, and five years were 94.8%, 84.1%, and 62.2%, respectively. The severity of liver disease progressed with time; 8% of patients developed cirrhosis within two years. The survival rate did not show any relation between HCV recurrence and the type of immunosuppression. In conclusion, although the survival of patients with HCV was not statistically significant compared to those with PBC or PSC, there was a trend towards a lower five-year survival in HCV.  相似文献   
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