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101.
Dermatomyositis is a rare inflammatory myopathy with characteristic skin manifestations and muscular weakness. The disease can be categorized as adult idiopathic, juvenile, or amyopathic dermatomyositis as well as that associated with a connective tissue disease or a malignancy. Immunologic factors are most likely involved in the pathogenesis of the disease; however, genetic and environmental issues may also play important roles. Treatment with immunosuppressive agents has proved successful in the majority of patients, although significant morbidity still occurs. 相似文献
102.
CI Coiré E Horvath K Kovacs HS Smyth H Sasano K Iino DS Feig 《Canadian Metallurgical Quarterly》1998,42(3):650-654
Recently, perfusion imaging has been of increasing interest in MRI. We applied this method for semiquantitative evaluation of hepatic parenchymal portal blood flow in patients with diffuse liver damage. Twenty patients with diffuse hepatic damage were divided according to the Child's Classification and studied. Gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) was administered into the superior mesenteric artery (SMA), and a dynamic series of T2*-weighted fast low angle shot (FLASH) images was obtained. We evaluated relative regional portal blood volume (rrPBV), mean transit time (MTT), and relative regional portal blood flow (rrPBF). The relationship between the rrPBV, rrPBF, and plasma indocyanine green retention rate test at 15 minutes (ICGR15 was also evaluated in 12 patients. Both rrPBF and rrPBV are significantly decreased in Child B & C patients compared with Child A patients. On the other hand, the MTT is significantly prolonged in Child B & C patients compared with Child A patients. Significant correlations were also noted between rrPBV and ICGR15 and between rrPBF and ICGR15. By means of selective catheterization into the SMA, we were able to estimate rrPBV, rrPBF, and MTT. This method may play a clinical role for assessment of regional portal perfusion in various diseases with diffuse liver damage. 相似文献
103.
H Kovacs ID Campbell P Strong S Johnson FJ Ward KB Reid P Eggleton 《Canadian Metallurgical Quarterly》1998,37(51):17865-17874
Calreticulin (CRT) is located predominantly in the endoplasmic reticulum (ER) of cells, where it functions as a quality control controller of protein folding. However, CRT is also a prevalent autoantigen in patients with systemic lupus erythematosus (SLE), where its release from the cell may arise as a results of dysfunctional apoptosis and inefficient removal of ER vesicles, which are an abundant source of CRT and other autoantigens. Indicative of this is the presence of autoantibodies against CRT in the sera of 40-60% of all SLE patients. Once released into the circulation, CRT might bind directly to C1q and we have suggested that this association may result in a defect in C1q-mediated clearance of antigen-antibody complexes. It has been previously shown that CRT under physiological salt conditions binds to the globular head of C1q. It is known that the globular head region of C1q binds to the CH2 domain in the Fc portion of immunoglobulin gamma (IgG). The N-terminal half of CRT contains a number of short regions of 7-10 amino acids that show sequence similarity to the putative C1q binding region in the CH2 domain of IgG. By use of a series of 92 overlapping CRT synthetic peptides, a number of C1q binding sites on the CRT molecule have been identified, including several containing a CH2-like motif similar to the ExKxKx C1q binding motif found in the CH2 domain of IgG. A number of these peptides were shown to inhibit binding of C1q to IgG and reduce binding of native CRT to C1q. Moreover, several of the peptides were capable of inhibiting the classical pathway of complement activation. These studies have identified specific binding sites on the CRT molecule for C1q and lend support to the hypothesis that interaction of CRT with C1q may interfere with the ability of C1q to associate with immune complexes in autoimmune-related disorders. 相似文献
104.
The traditional approach in epidemiology of relating exposure to an environmental agent such as a drug or infective agent has been to measure an overall risk (i.e., average and then "adjust risk for demographic variables and other confounders"). An attempt is sometimes made to define a "susceptible" subgroup. The analyses are usually based on good statistical methodology rather than an understanding of the interaction of body of host and agent. A twofold risk for 1000 exposed versus nonexposed people could be an average twofold risk for all 1000 exposed or a 20-fold risk for 100 exposed individuals (i.e., a drug-host interaction). Clearly, finding the 100 individuals with a 20-fold risk has much greater clinical importance than a twofold risk for 1000 people. The world of epidemiology may be changing-we may soon be able to define risk based on genetic susceptibility, at least sometimes. 相似文献
105.
Kovacs Maria; Iyengar Satish; Goldston David; Obrosky D. Scott; Stewart James; Marsh Judith 《Canadian Metallurgical Quarterly》1990,58(2):189
Mothers of children with newly diagnosed insulin-dependent diabetes mellitus (IDDM) were assessed repeatedly over a period of 6 years in order to determine the psychological correlates of managing this chronic illness. Both maternal depression and overall emotional distress after the 1st year of the IDDM increased slightly with illness duration and were also influenced by other factors. Mothers' adjustment shortly after their children were diagnosed with IDDM was a strong predictor of their long-term emotional symptomatology. However, mothers' symptoms over time were not related to medical aspects of IDDM (i.e., the extent of the children's metabolic control, number of rehospitalizations, or their compliance with the medical regimen) and were also unrelated to the levels of depression or anxiety reported by their children. Mothers generally found it easier to cope with the IDDM the longer their children had the illness. However, the degree to which mothers perceived the IDDM to be bothersome or difficult to manage at any given point in time was associated with their overall levels of emotional distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
A unique approach to attain enhanced, natural safety at low costs is given with a new, low temperature, low power level, nuclear energy plant of advanced design: the Geyser. The Geyser District Heating Nuclear Energy Plant (GDHNEP) and an ordinary low-temperature steam-cycle, the Geyser Thermal Energy Converter (GTEC), represent together a system possessing of remarkable features. Estimates project, that relatively small district heating plants distributed over a district heating network, or operating autonomously, would be cost effective. As a co-generation device the Geyser system may supply ample heating power and/or electricity opening new alternatives. 相似文献
107.
G.J. Kovacs 《Thin solid films》1979,60(1):33-44
The method of attenuated total reflection (ATR) was used to excite optically surface plasma waves (SPWs) in thin indium films. Three successive layers of MgF2/In/MgF2 were evaporated onto the base of a glass prism which had a high refractive index. Continous thin films of indium were obtained by maintaining the substrate at liquid nitrogen temperature during deposition. The ATR angular spectra and associated resonant oscillations were studied at three different wavelengths in the visible region and good agreement was obtained between the experimental and the calculated spectra. The symmetric SPW of the indium film was more highly attenuated than the antisymmetric SPW. Owing to the high damping of the plasma in indium only the antisymmetric SPW could be excited via an optical reflectance resonance when the indium slab was isolated by thick dielectric layers. With thinner bounding dielectrics two SPW-type resonances were observed. Complete calculations of the magnetic field oscillations within the variousmedia, as well as calculations of the current distributions and surface charge densities of the indium film, showed resonant oscillations of mixed symmetry. 相似文献
108.
109.
110.
A survey of direct patient care and nondirect patient care volunteers in two hospice programs generated information about various aspects of their volunteer experience. This paper focuses on the effectiveness of identified recruitment strategies for direct patient care, clerical, and fundraising volunteers. People learned about the opportunity to volunteer at hospice most frequently from personal experiences, friends, and newspapers. Significantly more direct patient care volunteers learned about the volunteer opportunity through newspaper feature stories than did nondirect volunteers. Friends recruited significantly more fundraising volunteers than direct patient care or clerical volunteers. The events triggering direct care and clerical volunteers to serve were most often personal experiences, whereas friends appear to have triggered direct care and fundraising volunteers to serve. 相似文献