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41.

Background  

Osteonecrosis of the femoral head (ONFH) is a debilitating condition affecting primarily young patients. Free vascularized fibular grafting (FVFG) may provide a durable means to preserve the femoral head. When used in the precollapse stages of ONFH, this treatment may alter the course of disease.  相似文献   
42.
The effect on ketonemia of alternate exposure to ambient temperatures (Ta) of 25 and 5°C was investigated in fasting geese. Three experimental birds were compared to three controls continuously exposed to 25°C Ta while fasting. During the first 9 days of fasting, when both groups were exposed to 25°C, plasma concentration of -hydroxybutyrate (-OHB) increased similarly in both, from 0.10±0.02 to 6.62±0.71 mmol·L–1. It later plateaued at 8–9 mmol·L–1 in the control birds. When the experimental birds were exposed to 5°C Ta between the 9th and 15th day of the fast, it increased further during the first 24 h but thereafter decreased of 57%, from 8.62±1.56 to 3.73±1.24 mmol·L–1. This decrease was reversed within the 6 days of return to 25°C Ta. In both groups, plasma acetoacetate (AcAc) concentration remained very low during the fast: 51±1 mol·L–1. This reversible cold-induced effect on ketonemia may be used for investigating the possible role of ketone bodies in protein sparing during fasting.  相似文献   
43.
Kidneys obtained from donors after cardiac death (DCD) are known to have higher rates of primary nonfunction and delayed graft function (DGF) than heart beating cadaveric donor (CAD) kidneys, but little is known about long-term function of DCD grafts that survive to 1 year. To investigate the outcomes of renal transplant recipients whose DCD graft functioned for at least 1 year, this study analyzed data collected from 326 DCD graft recipients and 340 CAD-matched controls enrolled in a prospective, multinational, observational study--Neoral-MOST (Multinational Observational Study in Transplantation) (Novartis, Basel, Switzerland). No differences were found in the demographics or immunosuppression between the two groups. All patients received a Neoral-based immunosuppressive regimen. Donors after cardiac death graft recipients had a higher incidence of DGF (40% vs. 27% CAD; P < 0.001). One year glomerular filtration rate (GFR) and GFR-decline after 1 year were similar in DCD and CAD recipients (GFR 56 ml/min DCD vs. 59 ml/min CAD; GFR-decline -1.3 ml/min DCD vs. -1.4 ml/min CAD; P = not significant). Multifactorial analyses confirmed that GFR at 1 year was significantly influenced by donor age and gender, DGF, and acute rejection; however, DCD status was not an independent risk factor in cyclosporine-treated patients with grafts that had functioned for at least 1 year.  相似文献   
44.
Nonmelanoma skin cancers (NMSC) are the most common malignant tumors following solid organ transplantation. Risk factors for NMSC mainly include immunosuppression, age, sun exposure and patient phototype. Recent findings have suggested that autosomal dominant polycystic kidney disease (ADPKD) may increase the risk of developing NMSC. We performed a monocenter retrospective study including all kidney recipients between 1985 and 2006 (n = 1019). We studied the incidence of NMSC, solid cancers and post‐transplantation lymphoproliferative disease (PTLD), and analyzed the following parameters: age, gender, phototype, time on dialysis, graft rank, immunosuppressive regimen, history of cancer and kidney disease (ADPKD versus others). Median follow‐up was 5.5 years (range: 0.02–20.6; 79 838 patient‐years). The cumulated incidence of NMSC 10 years after transplantation was 12.7% (9.3% for solid cancers and 3.5% for PTLD). Autosomal dominant polycystic kidney disease and age were risk factors for NMSC (HR 2.63; P < 0.0001 and HR 2.21; P < 0.001, respectively) using univariate analysis. The association between ADPKD and NMSC remained significant after adjustments for age, gender and phototype using multivariate analysis (HR 1.71; P = 0.0145) and for immunosuppressive regimens (P < 0.0001). Autosomal dominant polycystic kidney disease was not a risk factor for the occurrence of solid cancers after transplantation (HR 0.96; P = 0.89). Our findings suggest that ADPKD is an independent risk factor for developing NMSC after kidney transplantation.  相似文献   
45.
We have presented a technique for reconstruction of the central band of the interosseous membrane in conjunction with surgical repair of the distal radial joint and radial head prosthesis. With this technique, we address all three anatomic structures that provide longitudinal stability of the forearm, specifically, (1) radial head replacement, (2) interosseous membrane reconstitution, and (3) TFCC repair.  相似文献   
46.
ObjectivesThe current paper presents firstly the Interpersonal Psychological Theory of Suicide (IPTS) and its interest in the risk of suicide in physicians and/or medical students and secondly an original study on 178 medical students.MethodsIn total, 178 medical students of the Université Libre de Bruxelles filled out an ad hoc questionnaire rating suicidal ideations (life-time), recent suicidal plans and recent suicidal ideations rated by the 9th item of the Beck Depression Inventory-II (BDI). The subjects completed the French version of the Interpersonal Needs Questionnaire (INQ) rating Perceived burdensomeness and Thwarted belongingness and the Acquired Capability for Suicide Scale (ACSS) as well as the Beck Depression Inventory-II (BDI-II). Among the 178 medical students, 95 had no suicide risk, 24 had life-time suicidal ideation, 28 had recent suicidal ideations and 26 had recent suicidal plans. The four groups were compared for gender and age as well as for the different rating scales using Chi2 tests or analyses of variance (ANOVA).ResultsThe four groups had no significant differences for age, gender and scores on the ACSS. ANOVA revealed significant differences for perceived burdensomeness, thwarted belongingness and depression. To control the potential effect of depression, analyses of covariance (ANCOVA) were done taking as covariate a subscale of the BDI-II rating the cognitive component of depression. The two ANCOVA were significant. Post hoc tests comparing two by two the different groups reported that students with recent suicidal ideations or suicidal plans have significantly higher thwarted belongingness than students without suicide risk or students with life time suicidal ideations. Moreover, higher level of perceived burdensomeness was found only in students with suicidal plans comparatively with the three other groups.ConclusionHigh levels of thwarted belongingness and perceived burdensomeness characterize medical students with recent suicidal ideations or suicidal plans independently of the level of depression.  相似文献   
47.
Background  The study of vitamin D status at population level gained relevance since vitamin D deficiency was recently suggested to trigger chronic disease. Aim of the study  We aimed to describe vitamin D status, its association with bone and mineral metabolism and risk factors for deficiency in adults over 40 years in Belgium. Methods  We conducted a cross-sectional survey in a stratified random sample of 401 subjects aged between 40 and 60 years living in Brussels, and drawn from 4 different ethnic backgrounds: autochthonous Belgian, Moroccan, Turkish and Congolese. 25-Hydroxyvitamin D (25OHD), parathyroid hormone (PTH), osteocalcin, C-telopeptide and bone mineral density was measured. Results  Three-hundred and six subjects (77%) showed 25OHD concentrations below 50 nmol/l,135 (34%) below 25 nmol/l and 18 (5%) below 12.5 nmol/l. The proportion of subjects with vitamin D deficiency was four times greater amongst those of Moroccan or Turkish descent compared with those of Congolese or Belgian descent. Moroccan subjects showed a significant higher PTH and bone marker concentrations compared to Belgian. Ethnicity, season and sex were independently associated with vitamin D deficiency in multivariate analysis. Conclusion  The prevalence of vitamin D deficiency is very high amongst the adult population of Brussels but immigrants are at greater risk. Given the established link between population health and adequate vitamin D status, a policy of vitamin D supplementation should be considered in these risk groups.  相似文献   
48.
49.
We used transgenic mice carrying the lacI reporter gene to study the mutagenesis potential of asbestos crocidolite. The animals were exposed by nose-only inhalation to an aerosol containing 5.75 mg/m(3) crocidolite dust for 6 hr/day and 5 consecutive days. After 1, 4, and 12 weeks, we examined four end points: the cytology of bronchoalveolar lavage, the lung load of crocidolite, the hydrophobic DNA adducts, and the mutations in the lacI reporter gene. Twelve weeks after exposure, nearly 10% of the inhaled fibers remained in the lung (227 +/- 103 ng/mg lung). There was evidence of a typical inflammatory response consisting of multinucleate macrophages at weeks 4 and 12, whereas immediately after the exposure, we observed numerous polymorphonuclear neutrophils. The mutant frequency significatively increased during the fourth week after the exposure: 13.5 [time] 10(-5) in the exposed group versus 6. 9 10(-5) in the control group. The induction factor, defined by the ratio of checked mutants of exposed mice to checked mutants of control mice, was 1.96. The mutation spectrum of control lung DNA and exposed lung DNA was similar, suggesting the possible involvement of a DNA repair decrease in crocidolite-treated animals. We used the (32)P-postlabeling method and did not detect any increase of either 5 mC or bulky adduct in treated mice. This is the first study that demonstrates asbestos mutagenicity in vivo after a nose-only inhalation.  相似文献   
50.
Summary The anticancer activity of carminomycin was investigated in a human tumor cloning assay. No efficacy could be identified in the WiDr and the MCF7 cell lines which were highly responsive to doxorubicin. In addition, drug testing experiments were carried out in samples of various malignancies freshly obtained from 86 patients of whom 54 had not received prior anthracyclines. A reduction in the number of tumor colony forming units by 50% or more was seen in 1/26 breast cancers, 1/22 ovarian cancers and 1/7 melanomas. Cross-resistance studies indicated that eight tumors were responsive to doxorubicin only and one to carminomycin only whereas two were sensitive to both and 73 were resistant to both. This in vitro Phase II study corroborates the disappointing clinical results achieved with carminomycin.  相似文献   
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