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21.
The experiment aims at the reduction of the upper limit on a hypothetical CPT violation in the antiproton-proton system. A radio-frequency mass spectrometer (RFMS) has been designed and built to make the comparison of the charge to mass ratios of and p by measuring the ratios of the cyclotron frequencies of and H ions. At present, the RFMS is installed on-line to the LEAR facility at CERN. The resolving power has been found to be close to 3 × 105 and it still could be improved. A decelerating system (RFQ) has been installed in order to decelerate antiprotons from 2 MeV to 200 keV and to match as well as possible the acceptance of the spectrometer. It is presently under test and data taking should take place in 1992.  相似文献   
22.
To confirm the existence and characterize the pathologic features of humoral (antibody-mediated) lung rejection, we prospectively studied 55 lung transplant recipients (24 male [44%] and 31 female [56%], age range 14 to 69 years [mean 45]). The time between transplantation and biopsy ranged from 2 to 1546 days (mean 274). We performed direct immunofluorescence with C3, immunoglobulin M, and immunoglobulin G antibodies on frozen sections of 106 transbronchial biopsies and one wedge biopsy and compared the results with 13 explanted lungs, one donor lung, and two controls. The histologic diagnoses of these 107 biopsies included acute cellular rejection (62, 58% [minimal 23, mild 33, moderate 5, and severe 1]), chronic rejection (eight, 7%), chronic vascular rejection (two, 2%), acute vasculitis (five, 5%), cytomegalovirus pneumonitis (two, 2%), acute pneumonia (two, 2%), acute organizing pneumonia (two, 2%), diffuse alveolar damage (one, 1%), no evidence of rejection or infection (30, 28%), lipoid pneumonia (one, 1%), and inadequate for histologic diagnosis (one, 1%). Eighty-nine of 106 (84%) transbronchial biopsies, the wedge biopsy, and control lungs were satisfactory for direct immunofluorescence, because each contained alveolate lung parenchyma and arterioles or venules. There was no demonstrable immunofluorescence in the wall of the blood vessels or in the lung parenchyma in any case. We conclude that (1) transbronchial biopsies and wedge biopsies provide adequate material to evaluate humoral rejection, and (2) in spite of the large population studied, the satisfactory material obtained, and the wide range of histologic diagnoses, we could not demonstrate the occurrence of humoral rejection in the lung.  相似文献   
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24.
Magnetic Resonance Materials in Physics, Biology and Medicine - Quantitative analysis in MRI is challenging due to variabilities in intensity distributions across patients, acquisitions and...  相似文献   
25.
An interleukin-6 (IL-6) response was detected in 81 patients with febrile urinary tract infections (UTIs). Bacteremic patients (n=24) had higher serum IL-6 at inclusion and throughout the first 24 h (P<. 01) and higher urine IL-6 from 6 h after start of therapy (P<.01) than did nonbacteremic patients (n=57). The serum and urine IL-6 responses remained elevated longer in the bacteremic group. Patients with clinical signs of pyelonephritis had higher serum and urine IL-6 concentrations than did other patients in the study population (P=.058, P<.01, respectively). IL-6 high responders had higher temperatures (P<.05) and C-reactive protein levels (P<.05, P<.01) than did low responders. The results demonstrate that IL-6 responses accompany febrile UTIs regardless of bacteremia and that the response reflects disease severity. The results suggest that IL-6 produced in the urinary tract can trigger the systemic host response in the absence of bacteremia.  相似文献   
26.
For the treatment of secondary hyperparathyroidism (HPTH-II) in dialysis patients and hypercalcemia in patients with parathyroid carcinoma. Calcimimetics are a new class of drugs approved in the European Community and the United States by the Food and Drug Administration that were designed to suppress parathyroid hormone (PTH) levels with a simultaneous reduction in serum calcium and phosphorus levels, and calcium phosphorus product (Ca x P). Hypocalcemia is a frequent finding during the correction phase of the HPTH-II with calcimimetics. By contrast, the appearance of a hypercalcemia has yet to be described. In this paper, we report a case of severe hypercalcemia of immobilization in a 40-year-old hemodialyzed woman treated by cinacalcet HCl for a severe HPTH-II (PTH>1,000 pg/mL). A kidney transplantation recipient 1983 to 1995, she was diagnosed with Charcot-Marie Tooth disease in 1991. She had multiple orthopedic interventions for kidney-related osteoarticular problems probably favored by the kidney graft and the immunosuppressive treatment. While she was receiving the maximum dose of 180 mg/day of cinacalcet HCl and PTH at 443 pg/mL, she needed to be hospitalized for a right hip prothesis. Two weeks after the intervention she developed a symptomatic hypercalcemia of 3.57 mmol/L which was resistant to several measures including lowering the calcium concentration in the dialysate, withdrawing all vitamin D and calcium supplementation and the administration of calcitonin. Her serum calcium level was finally stabilized in the 2.37-2.95 mmol/L by administration of a single intravenous dose of pamidronate. This observation illustrates that the pharmacological activation of the parathyroid CaR and other putative CaR on bone cells by calcimimetics did not protect against the occurrence of hypercalcemia of immobilization favored by a severe HPTH-II in a hemodialysis patient.  相似文献   
27.
Since the first case reported in 1981, more than 60 million individuals have succumbed to HIV worldwide. Although great efforts have been put forth in developing therapeutic drugs and effective vaccines for the treatment and prevention of HIV infection, these efforts are not correlated to the reported case of cured HIV infection. The first case of cured HIV infection, from allogenic stem cell transplantation, may shed light on future prevention and therapy of HIV infection. The choice of gene target, however, must first be evaluated regarding stem cell based gene therapy for HIV infection. Out of the tens of genes that had shown anti-HIV infection potentials, CCR5 was described to be effective in stem cell based gene therapy in 2005. Here, we appreciate the clinical observations that directly led to the choice of CCR5, rather than other genes for stem cell gene therapy.  相似文献   
28.
After measurement of individual growth rates, natural hair fibres from Asian and Caucasian subjects were analysed using scanning electron microscopy. In total, more than 1000 hairs were analysed. Measurements of diameter, medulla and interscale distance (average distance between two successive cuticle scales) show these parameters strongly correlated with hair growth rate. A thicker hair fibre corresponds to a faster growth rate, a shorter interscale distance and greater probability to have a medulla, and vice versa, a thin hair fibre shows slower growth rate, a larger interscale distance and a lower probability to have a medulla. Very interestingly, this finding appears to be unrelated to the ethnic origin of the subjects, suggesting a common characteristic of human hair, at least for the straight or semi-straight hair studied. From a practical viewpoint, this finding clearly suggests an alternative method for measuring hair growth rates, by measuring the interscale distance, which appears easier than using common laboratory equipments.  相似文献   
29.
Our general objective is to point out, by mathematical modelling, the correlations between the topography of rough surfaces and, some characteristic quantities about their thermal or thermoelastic contact.In a first approach [which was described at the 3rd International Conference on Metrology and Properties of Engineering Surfaces (Ref. 1)], we considered the pure thermal conducting contact; we have then neglected the thermomechanical effects (pressures, stresses, strains), the presence of several competitive small reduced parameters (thickness and proportion of contact, relative conductivity of the interstitial fluid), and also the possibility of a radiative contribution at the level of the interstices.In this paper we describe the first attempts to take into account all these realistic effects.  相似文献   
30.
The aim of this project is to develop a new system for single ion irradiation of cells for genetic and cell biology studies. This charged particle focused microbeam system will provide a fully computer controlled irradiation facility with submicron (subcellular) resolution and will open many new avenues into studies of radiobiological mechanisms. In the first stage of this project a system for single ion detection has been developed. A thin diamond window has been tested as vacuum/atmosphere window and as a possible source of secondary electrons and/or photons for single ion detection. A detection efficiency of 97% has been achieved.  相似文献   
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