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61.
BackgroundAddition of vitamin E to polyethylene is theorized to reduce the potential for oxidative wear in acetabular components. This paper presents a multicenter prospective cohort study that reports on outcomes from use of a Vitamin E–infused highly cross-linked polyethylene acetabular cup.MethodsPatients were recruited across nine medical institutions. Clinical outcome measures recorded were the Harris Hip Score, visual analogue score for pain and satisfaction. Evidence of implant loosening or osteolysis was collected radiologically. Cup survival and reasons for revision in relevant cases were also recorded. Data collection was undertaken preoperatively, at 6-12 weeks, 6 months, 1 year, 2 years, and 5 years. A total of 675 patients were recruited, with 450 cases available at final review. Data regarding cup survival was available to 8 years and 9 months postoperatively.ResultsImprovements in both the Harris Hip Score and visual analogue score for pain and satisfaction were recorded at all time points, with these being maintained through the length of follow-up. In total, 89% of cups were implanted within the Lewinnek safe zone. A lucent line was identified in one case, with no evidence of acetabular osteolysis observed throughout the follow-up period. Cup survival was 98.9% at 8 years and 9 months. No revisions for aseptic loosening were observed.ConclusionsThe use of a vitamin E–infused polyethylene acetabular cup demonstrates reassuring patient-reported outcomes, radiological measures, and cup survival at medium to long-term follow-up.  相似文献   
62.
BackgroundIn the first year of dialysis, patients are vulnerable to cardiovascular disease (CVD) hospitalization, but knowledge regarding the risk factors and long-term outcomes of cardiovascular readmission within the first year after dialysis in incident continuous ambulatory peritoneal dialysis (CAPD) patients is limited.MethodsThis retrospective cohort study was conducted in incident CAPD patients. The demographic characteristics, laboratory parameters, and CVD readmission were collected and analyzed. The primary outcome was all-cause mortality, and the secondary outcomes included CVD mortality, infection-related mortality and technique failure. A logistic regression was used to identify the risk factors associated with CVD readmission within the first year after dialysis. Cox proportional hazards models were used to evaluate the association between CVD readmission and the outcomes.ResultsIn total, 1589 peritoneal dialysis (PD) patients were included in this study, of whom 120 (7.6%) patients had at least one episode of CVD readmission within the first year after dialysis initiation. Advanced age, CVD history, and a lower level of serum albumin were independently associated with CVD readmission. CVD readmission within the first year after dialysis was significantly associated with all-cause (HR 2.66, 95%CI 1.91–3.70, p < 0.001) and CVD (HR 3.42, 95%CI 2.20–5.31, p < 0.001) mortality, but not infection-related mortality or technique failure, after adjusting for confounders.ConclusionsOur findings suggest that an advanced age, a history of CVD, and a lower level of serum albumin were independently associated with CVD readmission. Moreover, CVD readmission was associated with all-cause and cardiovascular mortality in incident CAPD patients.  相似文献   
63.
64.
There is a high prevalence of suicide amongelderly Chinese, and particularly among elderly Chinesewomen in Mainland China with a prevalence of 19.6 perhundred thousand. Since Chinese individuals may much more highly value education, acognitive-behavioral package originated by RicardoMunoz, Ph.D. was adapted for Chinese American subjects.The material was videotaped in eight sessions,approximately 25 minutes in length, to be shown to communitysubjects who were at least 40 years and over. Inaddition, a videotape of muscular relaxation techniqueswas made. A manual written in Chinese about the content of each class, was given to each subject whenhe/she attended. The experimental group showedsignificant improvement in the scores in the HamiltonDepression Scale, including the Somatic Subscale in the Hamilton Anxiety Scale. There was nosignificant improvement in the control group on any ofthe measures. Thus the study suggests the efficacy ofpsychoeducational classes in reducing symptoms ofdepression in non-patient community elderly. Other studiesare being conducted among Korean Americans and JapaneseAmericans in the United States, and also in the Orientamong Japanese elderly.  相似文献   
65.
Pyo H  Jou I  Jung S  Joe E 《Neuroreport》1999,10(1):37-40
The beta-amyloid peptide (Abeta) has been known to activate microglia and to induce release of nitric oxide (NO). In this study, we examined the effect of cAMP on Abeta-induced microglial activation using cultured rat brain microglia. Dibutyryl-cAMP (dbcAMP) and 3-isobutyl-1-methylxanthine (IBMX) significantly potentiated Abeta(25-35)- or Abeta(1-42)-induced NO release in a dose-dependent manner. The increase in NO release was due to the increased expression of inducible nitric oxide synthase (iNOS). However, forskolin, an adenylate cyclase activator, weakly increased NO release at 10-50 microM but caused a decrease at 100 microM. These results suggest that increase in intracellular cAMP could potentiate microglial activation induced by Abeta.  相似文献   
66.
Summary As determined by a colorimetric assay measuring parent compounds plus ether-extractable, nitroso-containing metabolites, N,N-bis(2-chloroethyl)-N-nitrosourea (BCNU) disappeared more rapidly than N-(2-chloroethyl)-N cyclohexyl-N-nitrosourea (CCNU) and N-(2-chloroethyl)-N-(4-transmethylcyclohexyl)-N-nitrosourea (MeCCNU) and their products from the tissues of mice injected IV. Assay of selected samples by high-pressure liquid chromatography revealed that the colorimetric assay for BCNU was specific in that the two assays gave equivalent results. Following IV-injections of CCNU and MeCCNU, however, levels of the parent compounds decreased much more rapidly than the total, color-producing material.Of seven tissues, the largest Cxt values for BCNU, as determined by the colorimetric assay, were noted for blood (442 g-min/ml) and large intestine (285 g-min/g). Liver (29 g-min/g) had the lowest Cxt value, reflecting rapid metabolism of the compound by this organ. Color-producing material related to CCNU disappeared from the solid tissues of mice in a manner generally parallel to that for blood. Of the Cxt values for this compound and its products, those for lung (1753 g-equivalents-min/g), kidney (1633 g-equivalents-min/g), and small intestine (1557 g-equivalents-min/g) were highest. Consistent with its slower rate of metabolism, MeCCNU and its color-producing metabolites remained in most tissues of mice for 12 h following injection. Except for brain (1434 g-equivalents-min/g), Cxt values for this nitrosourea and its metabolites in tissues were higher than those of blood (5485 g-equivalents-min/ml), with kidney (15,324 g-equivalents-min/g), liver (12,921 g-equivalents-min/g), and large intestine (11,501 g-equivalents-min/g) being highest. For each nitrosourea, a fair correlation was observed between the Cxt values for tissues and the toxic and/or antitumor effects at those sites.  相似文献   
67.
We evaluated the visual results and success rate with a center-near concentric simultaneous vision bifocal contact lens. Forty subjects (screened from 175 presbyopic applicants) entered the study and were fitted with the CIBA Spectrum bifocal lenses (BCL) and also with single vision distance contact lenses combined with reading glasses (DCL). Visual acuity and stereoacuity measurements were made at dispensing and after 8 weeks of regular bifocal contact lens wear. At both times, visual acuity measurements with BCL were significantly reduced by 1-1.5 lines compared to DCL. Stereoacuity was reduced by 32-36" with BCL compared to DCL. Thirty-two patients completed the study and 27 chose to continue wearing BCL after completion of the study. None of the subjects had adverse corneal findings or problems of discomfort. The primary reason for BCL discontinuation was blurred vision. The data was retrospectively analyzed to identify risk factors for discontinuance--none were significant.  相似文献   
68.
Addict death rates during a four-year posttreatment follow-up.   总被引:3,自引:2,他引:1       下载免费PDF全文
Mortality rates were examined among 3,324 Black and White daily opioid drug users for a four-year period following treatment in community-based agencies located across the United States. A total of 179 of these addicts died during this follow-up period, yielding a death rate of 15.2 per 1,000 person-years at risk. When adjusted for age, addict death rates were found to be three to 14 times higher than those in the general US population. Life table analysis was also used to examine these rates in relation to client demographic, background, and treatment variables obtained prospectively, both prior to and during treatment. Age, alcohol use, and criminal history were positively associated with higher death rates. With regard to causes of death, age proved to be the only significant predictor; older addicts (over 30) had the highest percentages of deaths due to "natural" causes, while over three-fourths of the deaths among younger addicts were drug related or involved violence.  相似文献   
69.
These experiments were performed to examine the effects of graded doses of diazepam, flurazepam, or lorazepam given to Swiss-Webster mice either 30 min prior to training or immediately after training in a one-trial inhibitory (passive) avoidance task. A 350 A footshock was administered following entry into a darkened compartment and retention was tested three days later. Doses of 10.0 mg/kg diazepam and 20.0 mg/kg lorazepam given before training significantly impaired acquisition, while 1.0 mg/kg flurazepam, given immediately after training, produced retrograde amnesia. These results indicate that benzodiazepines affect memory processes and that various drugs of the benzodiazepine family differentially affect acquisition and memory consolidation.  相似文献   
70.
Squaxon (1,1'methylenedi-2 napthol; bis (2 hydroxy-1-napthyl) methane) was discovered by MacPhee and Ruelle (1968, 1969) to exhibit piscicidal properties that are highly species specific. The chemical is lethal to the Northern (Ptychocheilus oregonensis) and the Umpqua (P. umpquae) squawfish, freshwater cyprinids common to the Pacific Northwest, at water treatment concentrations of less than 100 parts per billion (ppb). Other species of fish, including the more desirable salmonids with which the squawfish competes ecologically, are unaffected until this dosage has been increased severalfold. Because squawfish are widely regarded as undesirable for food or sporting purposes, and because competition from squawfish has severly depleted salmonid populations in some areas (Thompson, 1959; Jeppson and Platts, 1959) the potential use of squaxon for fisheries improvement is quite obvious. Squaxon is currently being tested for this purpose on an experimental basis in selected areas in Idaho, Oregon and Washington, pending federal clearance for more widespread application.Commercially formulated squaxon currently being field tested is dispersed as an ethanolic solution of the monosodium salt. The treatment solution consists of 39.5 per cent (by weight) 1,1 methylene-di-2 napthol dissolved in 60 per cent denatured ethyl alcohol. Traces of sodium hydroxide are also present in the commercial solution (Keating, 1972). We report here an analytical method by which petroleum ether-extracted, brominated squaxon can be quickly and easily detected in water and fish tissue by electron capture gas chromatography.This research was supported under Contract No. 68-02-0552 by the Pesticide Community Studies Division, Pesticides Office Environmental Protection Agency, through the Idaho Department of Health and Welfare.  相似文献   
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