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排序方式: 共有437条查询结果,搜索用时 15 毫秒
1.
BACKGROUND: Most studies evaluating antibody detection assays are conducted on samples from healthy blood donors but not on samples of hospitalized patients which can show non-specific reactions. OBJECTIVES: To compare the performance of three commercial automated assays for the detection of hepatitis C virus (HCV) antibodies, Monolisa anti-HCV Plus version 2, Axsym anti-HCV 3.0 and Vitros anti-HCV, on a population of hospitalized patients. STUDY DESIGN: The specificity of the assays was prospectively evaluated in 2020 routine serum samples. In order to assign the serostatus of each sample, those giving positive or discordant results were further tested by three immunoblots and by RT-PCR (Roche). Moreover, the sensitivity was evaluated on eight commercial HCV seroconversion panels. RESULTS: The Monolisa, Axsym and Vitros assays showed specificities of 99.64%, 99.12% and 99.33%, respectively. Concerning the sensitivity, among 49 samples, the number of positive results was 21, 24 and 24 for the Monolisa, Axsym and Vitros kits, respectively. The differences were not statistically significant at an alpha risk of 5%. CONCLUSIONS: All assays appeared to be reliable for routine screening, but there were a surprising number of indeterminate samples that could not be resolved by confirmatory tests.  相似文献   
2.
Keratinocyte growth factor (KGF) is secreted by fibroblasts and protects from pulmonary fibrosis in animal models. Interleukin (IL)-1beta is the most potent inducer of KGF in fibroblasts, acting through the c-Jun pathway. We evaluated in vitro KGF production by human lung fibroblasts from patients with idiopathic pulmonary fibrosis (IPF, n = 10) and from control subjects (n = 7) at baseline and after IL-1beta stimulation. Basal KGF secretion by IPF fibroblasts was similar to controls. In fibroblasts from control subjects, IL-1beta increased c-Jun expression, c-Jun activation, and KGF secretion. SP600125, a specific c-Jun N-terminal kinase (JNK) inhibitor, inhibited the effect of IL-1beta. By contrast, in IPF fibroblasts, IL-1beta did not increase c-Jun expression and c-Jun activation, and weakly increased KGF secretion, whereas SP600125 had no effect. IL-1beta similarly increased JunB expression in fibroblasts from patients with IPF and control subjects. Total JNK content was not different in either unstimulated or IL-1beta-stimulated IPF and control fibroblasts. IL-1beta increased phosphorylated JNK in control and IPF fibroblasts, but this increase was weaker and heterogeneous in IPF. Altogether, our results demonstrate a dysregulation of KGF secretion by IPF fibroblasts. The weak response to IL-1beta is associated with a defect of c-Jun expression and activation and a defect of JNK activation.  相似文献   
3.
The objective of the present review is to provide an overview of existing research that has reported on the association between posttraumatic stress disorder (PTSD) and ischemic heart disease. Specific focus is given to the incidence of PTSD following myocardial infarction (MI). A systematic review using Preferred Reporting Items for Systematic reviews and Meta‐Analysis (PRISMA) guidelines was performed by searching four bibliographic databases: PubMed, PsychINFO, ScienceDirect, and ProQuest Dissertations and Theses. A total of 39 articles were included in this literature review. The results of these studies suggest that the occurrence of an acute cardiac event is likely to contribute to the development of PTSD. Not only is this type of psychiatric disorder associated with significant suffering and impaired quality of life, but it is also a predictor of an increased risk of recurrent adverse cardiovascular events and mortality. Screening, assessment, and treatment of PTSD and posttraumatic stress symptoms following a major cardiac event are critical for offsetting potential deleterious psychological and physical consequences.  相似文献   
4.
 As it is suggested that the androgen receptor mechanism is required for prostatic development, we attempted to determine the appearance, expression and distribution of the androgen receptor in embryonic, infantile and pubertal human prostate. Using mono- and polyclonal antibodies and a digoxigenin-labeled 713 bp riboprobe, the androgen receptor expression in paraffin sections of fetal, infantile, and pubertal prostates was studied at the protein and RNA level. Under highly standardized conditions, application of the polyclonal antibodies resulted in a weak cytoplasmic and nuclear labeling of the epithelium of fetal glands. No immunoreaction was obtained with monoclonal antibodies. Applying the polyclonal antibody to pubertal and adult specimens, immunoreactivity of the androgen receptor was positive in nuclei of adluminal and basal epithelial cells, in interstitial and vascular smooth muscle cells and vascular endothelium, whereas ganglionic cells and enteroendocrine cells were negative. In situ hybridization with the digoxigenin-labeled riboprobe gave clear positive results already in epithelium of very young fetal specimens. A semiquantitative visual evaluation of in situ hybridizations showed that intermediate intensity of expression was increased in pubertal and adult specimens, whereas strong expression was reduced in prostatic epithelium. Conclusions: The essential findings are: (1) an early expression of androgen receptor mRNA in the fetal prostate; (2) no immunoreaction of monoclonal antibodies against the androgen receptor in the same specimens, (3) a decrease of androgen receptor mRNA expression, but increase in immunoreactivity of the androgen receptor protein with the onset of glandular maturation during puberty. Accepted: 29 September 1997  相似文献   
5.
PURPOSE: To determine incidence of non-AIDS-defining cancers (NADC) in HIV-infected patients before (P1) and during (P2) the use of highly active antiretroviral therapy (HAART) relative to that observed in the French general population (FGP) of the same age and sex. PATIENTS AND METHODS: Sex- and age-adjusted NADC standardized incidence ratios (SIR), with FGP as reference, were estimated in 1992 to 1995 (P1) and in 1996 to 1999 (P2) in a French Hospital Database on HIV prospective hospital cohort study. RESULTS: NADCs were diagnosed in 260 patients during P1 and 391 patients during P2 among the 77,025 patients included in the database between January 1, 1992, and December 31, 1999. Estimated incidence of all cancers was higher in HIV-infected men than in FGP during both periods (P1 SIR = 2.36 and P2 SIR = 1.91). No excess of cancers was observed among HIV-infected women in either period. Incidence of all cancers did not change from P1 to P2 in either sex (SIR = 0.96 for men and 1.00 for women). In contrast, incidence of Hodgkin's disease (HD) was higher than in FGP in both sexes and both periods and increased in P2 as compared with P1; incidence of lung cancer was higher in both sexes during P2. CONCLUSION: Relative to FGP, the overall incidence of NADCs was increased in HIV-infected men but not in women and did not differ between P1 and P2. Only HD was much more common in HIV infection, and the potential role of HAART on HD cannot be excluded.  相似文献   
6.
We report on the crystallite growth of nanometric NpO2 and UO2 powders. The AnO2 nanoparticles (An = U and Np) were synthesized by hydrothermal decomposition of the corresponding actinide(iv) oxalates. NpO2 powder was isothermally annealed between 950 °C and 1150 °C and UO2 between 650 °C and 1000 °C. The crystallite growth was then followed by high-temperature X-ray diffraction (HT-XRD). The activation energies for the growth of crystallites of UO2 and NpO2 were determined to be 264(26) kJ mol−1 and 442(32) kJ mol−1, respectively, with a growth exponent n = 4. The value of the exponent n and the low activation energy suggest that the crystalline growth is rate-controlled by the mobility of the pores, which migrate by atomic diffusion along the pore surfaces. We could thus estimate the cation self-diffusion coefficient along the surface in UO2, NpO2 and PuO2. While data for surface diffusion coefficients for NpO2 and PuO2 are lacking in the literature, the comparison with literature data for UO2 supports further the hypothesis of a surface diffusion controlled growth mechanism.

We report on the crystallite growth of nanometric NpO2 and UO2 powders.  相似文献   
7.
Objectives  Little is known regarding the distribution and the determinants of leptin and adiponectin levels in the general population.
Design  Cross-sectional study.
Patients  Women (3004) and men (2552) aged 35–74 living in Lausanne, Switzerland.
Measurements  Plasma levels of leptin and adiponectin (ELISA measurement).
Results  Women had higher leptin and adiponectin levels than men. In both genders, leptin and adiponectin levels increased with age. After adjusting for fat mass, leptin levels were significantly and negatively associated with age in women: 18·1 ± 0·3, 17·1 ± 0·3, 16·7 ± 0·3 and 15·5 ± 0·4 ng/ml (adjusted mean ± SE) for age groups [35–44], [45–54], [55–64] and [65–75], respectively, P  < 0·001. A similar but nonsignificant trend was also found in men. Conversely, the age-related increase of adiponectin was unrelated to body fat in both genders. Post-menopausal women had higher leptin and adiponectin levels than premenopausal women, independently of hormone replacement therapy. Although body fat mass was associated with leptin and adiponectin, the associations were stronger with body mass index (BMI), waist and hip in both genders. Finally, after adjusting for age and anthropometry, no relationships were found between leptin or adiponectin levels with alcohol, caffeine consumption and physical activity, whereas smoking and diabetes decreased leptin and adiponectin levels in women only.
Conclusions  The age-related increase in leptin levels is attributable to changes in fat mass in women and probably also in men. Leptin and adiponectin levels are more related to BMI than to body fat mass. The effects of smoking and diabetes appear to be gender-specific.  相似文献   
8.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated coronavirus disease 2019 (COVID-19) is primarily manifested as a respiratory tract infection, but may affect and cause complications in multiple organ systems (cardiovascular, gastrointestinal, kidneys, haematopoietic and immune systems), while no proven specific therapy exists. The challenges associated with COVID-19 are even greater for patients with light chain (AL) amyloidosis, a rare multisystemic disease affecting the heart, kidneys, liver, gastrointestinal and nervous system. Patients with AL amyloidosis may need to receive chemotherapy, which probably increases infection risk. Management of COVID-19 may be particularly challenging in patients with AL amyloidosis, who often present with cardiac dysfunction, nephrotic syndrome, neuropathy, low blood pressure and gastrointestinal symptoms. In addition, patients with AL amyloidosis may be more susceptible to toxicities of drugs used to manage COVID-19. Access to health care may be difficult or limited, diagnosis of AL amyloidosis may be delayed with detrimental consequences and treatment administration may need modification. Both patients and treating physicians need to adapt in a new reality.  相似文献   
9.
BACKGROUND: In the current context of dyslipidaema, hyperglycaema and lipodystrophia observed among HIV-seropositive subjects, it is important to study the risk of myocardial infarction (MI) in this population. The French Hospital Database on HIV, which includes a large number of seropositive subjects followed for substantial periods, offers the opportunity to analyse the impact of protease inhibitors (PI) on the risk of MI among men. METHODS: Cox model was used to study the risk factors of MI occurrence. Standardized morbidity ratios (SMR) in men exposed to PI were calculated with data from the French general male population (FGMP) of the same age as reference. RESULTS: Between 1996 and 1999, MI was diagnosed in 60 men among 88 029 person-years (PY), including 49 cases among men exposed to PI. In the Cox model, exposure to PI was associated with a higher risk of MI [relative hazard (RH), 2.56; 95% confidence interval (CI), 1.03-6.34]. The expected incidence in the FGMP was 10.8/10,000 PY. The SMR relative to the FGMP was 0.8 (95% CI, 0.5-1.3) for men exposed to PI for < 18 months (G1), 1.5 (95% CI, 0.8-2.5) for men exposed for 18-29 months (G2) and 2.9 (95% CI, 1.5-5.0) for men exposed for >or= 30 months (G3). With G1 as reference, the SMR was 1.9 (95% CI, 1.0-3.1) for G2 and 3.6 (95% CI, 1.8-6.2) for G3. CONCLUSION: Our results point to a duration-related effect relationship between PI and MI, with a higher MI incidence rate among men exposed to PI for 18 months or more.  相似文献   
10.
In arterial replacement there is a clear clinical need for a functional substitute possessing appropriate haemocompatible properties to be implanted as small diameter artery. Endothelial cell seeding constitutes an appreciated method to improve blood compatibility on the condition that cells firmly adhere to the support. Along this way, an innovative technique based on multilayered polyelectrolyte films (PEM) as cell adhesive substrate was previously validated in vitro and in vivo in a small-animal model. In this study, we extended the work on a larger animal (sheep) to validate furthermore the paradigm of PEM functionalization for vascular substitutes. We tested in vitro: the efficiency of PEM to induce endothelial progenitor differentiation in sheep endothelial cells; the ability of PEM to sustain cell proliferation and allow resistance to shear stress; the fate of PEM-coated de-endothelialized human saphenous veins under flow conditions, a prerequisite step before in vivo experiments. Despite in vitro differences we were encouraged by testing in vivo PEM-coated prosthesis as carotid replacement in sheep, but without success. In order to explain the implantation failure, an in vitro haemocompatibility evaluation was performed that highlighted interspecies differences able to explain, at least in part, the graft failure obtained.  相似文献   
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