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1.
This paper presents a full reconstruction process of magnetic resonance images. The first step is to bring the acquired data from the frequency domain, using a Fast Fourier Transform algorithm. A Tomographic Image Interpolation is then used to transform a sequence of tomographic slices in an isotropic volume data set, a process also called 3D Reconstruction. This work describes an automatic method whose interpolation stage is based on a previous matching stage using Delaunay Triangulation. The reconstruction approach uses an extrapolation procedure that permits appropriate treatment of the boundaries of the object under analysis.  相似文献   
2.
The Magnum system, initially designed for coronary angioplasty (PTCA) of chronic total occlusion, consists of a balloon catheter and a solid steel 0.021 inch (0.53 mm) steerable and removable wire with a soft and moldable distal portion, tipped with a 1 mm olive. To evaluate its performance in routine PTCA, 200 unselected consecutive patients were randomized to two equal groups, i.e., group Magnum (100 patients, 115 vessels) and group Standard (100 patients, 118 vessels) including 18 and 21 patients with chronic total occlusions, respectively. Randomization was performed by the sealed envelope system in the catheterization laboratory and crossover of system was imposed if it was not possible to place a balloon correctly within 20 min of fluoroscopy time. There were no significant differences between groups concerning clinical and angiographic baseline characteristics, size of initial balloons (3.0±0.3 mm in both groups), fluoroscopy time to cross the lesion with the wire (Magnum: 4±5, Standard: 5±6 min), total fluoroscopy time (Magnum: 11 ± 9, Standard: 12±12 min), and need for crossover (Magnum: 10%, Standard: 16%). Success rates per lesion were comparable with 90% in group Magnum and 84% in group Standard, as were the complications with one inhospital death in group Standard, occurring three weeks after PTCA and stent implantation. There was no emergency operation. Six patients per group had myocardial infarction of whom two in group Magnum and one in group Standard developed a Q-wave. The following variables were significantly in favor of the Magnum system compared with the Standard system: success rate in nontotal lesions (97% versus 90%) crossover success in total occlusions (0 vs. 33%), fluoroscopy time to cross the lesion with the balloon once the wire was in place (1 ± 2 vs. 2 ± 4 min), and use of a single versus 1.2±0.5 wires per lesion. The only advantage of the Standard systems was the more common use of 7 French guiding catheters (Magnum: 40%, Standard: 53%, p = 0.09). The Magnum system compares favorably with standard systems for routine PTCA. The robust design of the Magnum wire does not impair ease of placement and safety but saves material and facilitates balloon advancement across the lesion.  相似文献   
3.
The objective of the present work was to set up a routine test adapted to screening for antiendothelial cell antibodies (AECAs) in serum samples with minimal interference from antinuclear antibodies (ANAs) or rheumatoid factors (RFs). We compared the titers of AECAs titrated following two enzyme-linked immunosorbent assays (ELISAs): (i) an ELISA with ethanol-fixed EA.hy926 monolayers as the antigenic substrate and (ii) an ELISA with nucleus-depleted lysates prepared from EA.hy926 cells and normalized for protein (1.0 to 1.7 mg/ml) and DNA (≤0.1 μg/ml) contents as a surrogate substrate (postnuclear supernatant ELISA [PNS-ELISA]). The AECA titers in 51 serum samples, including 28 samples containing ANAs, were compared. A significantly positive correlation (r = 0.77; P < 0.001) between the two series was shown only for the ANA-negative serum samples. Conversely, ANAs or RFs in samples were shown not to interfere in tests for AECAs by the PNS-ELISA. AECAs recognize their antigenic targets in postnuclear supernatants, which is representative of the endothelial antigenic content, with improvement of the reliability of the assay, a prerequisite to application of the assay for their evaluation in clinical practice.  相似文献   
4.
The prevalence, incidence and risk factors of infectious diseases observed in the general population have been described to directly influence transfusion medicine, especially the blood selection. The objective is to ensure the blood safety. The characterization of modes of transmission influences the donor selection: the risk factors of the main blood‐borne infections have permitted to adapt the pre‐donation questionnaire in order to exclude at‐risk donors. The prevalence of infections also has an impact on the blood screening strategy. For example, anti‐HBc antibody (Ab) screening is currently performed only in countries where the HBV prevalence is compatible with a reasonable number of donor exclusions. HTLV Ab screening is implemented in countries in which the rate of donors originating from endemic areas could represent a risk for blood components. Measurement of incidence which contributes to the residual risk has led to the introduction of nucleic acid testing (NAT) for HIV, HCV and in some cases for HBV in viral screening strategy in many countries worldwide. The observed NAT yield differs according to the incidence of the infection and according to the country. Finally, the putative blood transmission of new and emerging pathogens has led to implement specific and non‐specific measures in order to enhance blood safety. Conversely, although the blood donor population is selected, the data observed in this population have also contributed to better understand epidemiology and pathogenesis of infection. Moreover, owing to the recent progress in developing modelling approaches for estimating risk, we are able to anticipate a transfusion transmission threat by introducing, when necessary, specific measures intended for reduce this risk.  相似文献   
5.
The effects of long-term chronic stress (induced by repeated restraint, overcrowding or both), short-term chronic stress (induced by a triad of stressors over a short period of time early in life) and adrenalectomy were investigated on the prevalence, on the degree of insulitis and various physiological and immunological parameters in the NOD mouse, a spontaneous model of type I-insulin-dependent diabetes mellitus (IDDM). Long-term chronic stress, obtained by restraint once a week or overcrowding, significantly protected NOD females, while both applied concomitantly had only a tendency to protect against diabetes. In contrast, short-term chronic stress had no significant effect on diabetes expression, whereas adrenalectomy resulted in a trend toward accelerated diabetes onset. The various long-term chronic stress paradigms exerted different effects on the progression of insulitis: repeated restraint tended to protect against insulitis, overcrowding had no effect but, when associated with restraint, significantly counteracted the beneficial effect of restraint alone. Adrenalectomy and short-term chronic stress had no significant effect on the development of insulitis. Various parameters, such as body, thymus and spleen weights, thymus and spleen cellularities, mitogen-induced spleen cell proliferation and serum corticosterone levels were also studied under the various experimental conditions. Taken together, the observations suggest that stressors modulate the expression of spontaneous autoimmune diabetes by exerting pleiotropic effects on immune and/or inflammatory components at the pancreas level and on peripheral glucose metabolism.  相似文献   
6.
Rosacea and cutaneous lupus erythematosus (CLE) are chronic inflammatory dermatoses. To our knowledge, no cases of granulomatous rosacea (GR) associated with CLE have been previously reported in the literature. We describe the case of a 38-year-old female patient who presented to our clinic with a diffuse scaly facial erythema, with the codiagnoses of GR and CLE later confirmed with clinicopathological correlation.  相似文献   
7.
To assess the ingestion of folate and nutrients involved in the 1-carbon cycle in non-treated patients with colorectal adenocarcinoma in a reference center for oncology in southeastern Brazil. In total, 195 new cases with colorectal adenocarcinoma completed a clinical evaluation questionnaire and a Food Frequency Questionnaire (FFQ). Blood samples from 161 patients were drawn for the assessment of serum folate. A moderate correlation was found between serum concentrations of folate, folate intake and the dietary folate equivalent (DFE) of synthetic supplements. Mulatto or black male patients with a primary educational level had a higher intake of dietary folate. Of patients obtaining folate from the diet alone or from dietary supplements, 11.00% and 0.10%, respectively, had intake below the recommended level. Of the patients using dietary supplements, 35% to 50% showed high levels of folic acid intake. There was a prevalence of inadequacy for vitamins B2, B6 and B12, ranging from 12.10% to 20.18%, while 13.76% to 22.55% of patients were likely to have adequate choline intake. The considerable percentage of patients with folate intake above the recommended levels deserves attention because of the harmful effects that this nutrient may have in the presence of established neoplastic lesions.  相似文献   
8.
In recent years, studies have increasingly employed data logger technologies to record objective driving and physiological characteristics of manual wheelchair users. However, the technologies used offer significant differences in characteristics, such as measured outcomes, ease of use, and level of burden. In order to identify and describe the extent of published research activity that relies on data logger technologies for manual wheelchair users, we performed a scoping review of the scientific and gray literature. Five databases were searched: Medline, Compendex, CINAHL, EMBASE, and Google Scholar. The 119 retained papers document a wide variety of logging devices and sensing technologies measuring a range of outcomes. The most commonly used technologies were accelerometers installed on the user (18.8%), odometers installed on the wheelchair (12.4%), accelerometers installed on the wheelchair (9.7%), and heart monitors (9.7%). Not surprisingly, the most reported outcomes were distance, mobility events, heart rate, speed/velocity, acceleration, and driving time. With decreasing costs and technological improvements, data loggers are likely to have future widespread clinical (and even personal) use. Future research may be needed to assess the usefulness of different outcomes and to develop methods more appropriate to wheelchair users in order to optimize the practicality of wheelchair data loggers.  相似文献   
9.
Individuals who are minoritized as a result of race, sexual identity, gender, or socioeconomic status experience a higher prevalence of many diseases. Understanding the biological processes that cause and maintain these socially driven health inequities is essential for addressing them. The gut microbiome is strongly shaped by host environments and affects host metabolic, immune, and neuroendocrine functions, making it an important pathway by which differences in experiences caused by social, political, and economic forces could contribute to health inequities. Nevertheless, few studies have directly integrated the gut microbiome into investigations of health inequities. Here, we argue that accounting for host–gut microbe interactions will improve understanding and management of health inequities, and that health policy must begin to consider the microbiome as an important pathway linking environments to population health.  相似文献   
10.
In addition to AIDS surveillance, data on HIV infection are necessary to better follow the dynamics of the epidemic. We report the first results of France's mandatory anonymous HIV notification system, which is linked to a virological surveillance of recent HIV infections and of circulating HIV types, groups and subtypes. HIV notifications are initiated by microbiologists who create an anonymous code of patient's identity. Clinicians complete the notification form with epidemiological and clinical data. Notifications are sent to the local health authorities and passed to the Institut de Veille Sanitaire (InVS). Laboratories voluntarily send sera from newly diagnosed HIV infected persons on dried blood spots to the national HIV reference laboratory where an immunoassay for recent infection (< or = 6 months) and a serotyping assay for the determination of group and subtype are done. The virological results are then merged at the InVS with the information from the mandatory reporting. Of the first 1301 new HIV diagnoses reported in 2003, 43% were in women, and overall, 53% were in heterosexuals, of whom 47% were of sub-Saharan African origin. MSM accounted for 36% of male notifications. A dried blood spot was available for 64% of new HIV diagnoses. Evidence of recent infection was found for 38%, ranging from 22% in IDUs to 58% in MSM. Twenty-six percent of infections in sub-Saharan migrants were recent infections. HIV-1 accounted for 98% of all notifications: 48% of these were non-B subtypes. The first results of the HIV notification system indicate that heterosexual transmission is the predominant mode of transmission and that persons originating from sub-Saharan Africa are particularly affected. Over half of infections shown to be recently acquired were in MSM; this may indicate an increased HIV incidence in this population.  相似文献   
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