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81.
Barge  AJ; Johnson  G; Witherspoon  R; Torok-Storb  B 《Blood》1989,74(5):1477-1480
Marrow graft failure observed in association with histocompatibility differences between donor and recipient is often attributed to rejection mediated by host-derived cytolytic T lymphocytes. The data presented in this report indicate that persistent host antibodies specific for donor antigen may also mediate graft failure, either by antibody-dependent cell-mediated cytotoxicity (ADCC), or complement- mediated cytotoxicity. In the case of HLA Class I disparity, where all donor cells express the target antigen, the presence of alpha-donor antibody was associated with complete graft failure and death. In the case of ABO blood group antigen disparity, the presence of alpha-donor antibody resulted in erythroid hypoplasia. The latter cases proved informative insofar as they established that host antibodies could persist for more than 18 months after chemoradiotherapy and impair marrow function.  相似文献   
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Background Psoriasis is a chronic, recurring inflammatory disease affecting the skin, joints and nails that has a significant negative impact on the quality of life. Efficacy of combination of methotrexate/narrowband ultraviolet B (NBUVB) phototherapy in the treatment of psoriasis has been rarely assessed. Objectives To compare the efficacy of methotrexate/NBUVB phototherapy combination vs. NBUVB phototherapy in the treatment of chronic plaque psoriasis. Methods Forty patients with chronic plaque‐type psoriasis (body surface area involvement >10%) were randomized to receive either methotrexate/NBUVB phototherapy (group A) or placebo/NBUVB phototherapy (group B). End point of treatment was 75% reduction in Psoriasis Area and Severity Index (PASI) Score or upto 6 months, whichever was earlier. Patients were then followed up for a period of 12 weeks for assessment of relapse. Results Of 40 patients, 37 completed the treatment period and 29 both the treatment period and follow‐up. PASI 75 was achieved in 19/20 patients in group A and 14/20 patients in group B (P < 0.04). The mean number of weeks(P = 0.001), the mean cumulative dose of NBUVB (P = 0.001) and the mean number of phototherapy sessions (P = 0.0001) required to achieve PASI 75 were significantly less in group A compared with group B. There was no significant difference in the number of patients who relapsed during the follow‐up period (P = 0.68). Conclusion Combination of methotrexate and NBUVB phototherapy provides more rapid clinical improvement compared with NBUVB monotherapy in the treatment for chronic plaque‐type psoriasis.  相似文献   
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A patient with severe ocular albinism was fitted with a prosthetic soft contact lens which improved both photophobic symptoms and facial cosmesis.  相似文献   
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Magnetic resonance (MR) images of the brain in 285 patients between the ages of 2 and 25 years were retrospectively studied to determine the appearance of brain iron accumulation. The globus pallidus, red nucleus, substantia nigra, and dentate nucleus were evaluated with long TR/TE (repetition time/echo time) spin-echo sequences and staged. All four regions in most patients were initially hyperintense compared with white matter (stage I) before becoming isointense (stage II) and subsequently hypointense (stage III). The globus pallidus was the first to reach stage III, the red nucleus and substantia nigra were next, and the dentate nucleus was last. In general, decreased signal intensity (stage III) was not seen in these regions in patients less than 10 years old; in most patients it was seen by age 25 years. The dentate nucleus decreased in signal intensity more slowly and inconsistently; only one-third of patients had reached stage III by age 25 years. The temporal sequence of normal iron deposition as detected with MR imaging is helpful not only in the diagnosis of known iron-deposition diseases but also in the detection of iron-related pathologic changes.  相似文献   
88.
Fox  AJ; Pelz  DM; Lee  DH 《Radiology》1990,177(1):51
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89.
Anxiety in patients undergoing MR imaging   总被引:6,自引:0,他引:6  
Quirk  ME; Letendre  AJ; Ciottone  RA; Lingley  JF 《Radiology》1989,170(2):463-466
To determine and quantify the major sources of anxiety for patients undergoing magnetic resonance (MR) imaging and to suggest means by which to eliminate or diminish their negative effects, the authors studied anxiety in 46 subjects. Of these, 20 randomly selected subjects who successfully completed the examination participated in exit interviews. Six subjects who terminated the examination before completion also completed exit interviews. Pre-imaging and postimaging questionnaires (state-trait anxiety inventory) were administered to measure anxiety in the 20 other subjects. Anxiety was associated with the constrictive dimensions of the magnet bore, examination duration, coil noise, and temperature within the bore. Preparation at the point of referral was consistently absent, incomplete, or misleading. Patients used identifiable strategies to cope with the examination: blinding, breathing relaxation techniques, visualization of pleasant images, and performance of mental exercises.  相似文献   
90.
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