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Smith  DK; Gilula  LA; Amadio  PC 《Radiology》1990,176(2):497-499
Excessive dorsiflexion (dorsal tilting) of the lunate on a lateral wrist radiograph can be an important sign of carpal injury. Lunate dorsiflexion is a well-recognized sign of an intercarpal ligamentous injury pattern known as dorsal intercalated segment instability (DISI). It is less well recognized that excessive dorsal tilting of the lunate (DISI configuration) can also be produced by displacement of a scaphoid waist fracture. Since the management and prognosis of displaced scaphoid fractures may be quite different from those for nondisplaced fractures, radiologists can make an important contribution by recognizing dorsal tilting of the lunate and appreciating that it may be an important, indirect sign of scaphoid fracture displacement, which may not be directly visualized with standard wrist radiography. In this setting, computed tomography or complex motion tomography may be helpful for further evaluation of the scaphoid fracture.  相似文献   
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本文依据一组含有不同比例待测和干扰组分的标准混合液的吸收值,采用一元线性回归方法,在选择最佳测定波长对的同时建立标准工作曲线方程,使其更符合实际作品测定时的情况,提高了结果的精度和可靠性,并使计算量和实验工作量得以降低。应用于复方氨基比林注射液中三组分氨基比林、安替比林和巴比妥的同时测定,其平均回收率分别为99.8%,100.4%和99.8%,变异系数分别为0.59,1.48和1.05,结果优于卡尔曼滤波法、偏最小二乘法和目标因子分析法。  相似文献   
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Chagas' disease patients (CDP) develop both humoral and cellular immune responses against the major cysteine proteinase (cruzipain) from Trypanosoma cruzi. Here we demonstrate that complexes formed by cruzipain and alpha 2-macroglobulin (alpha 2M) are efficiently internalized by human monocytes, and that this process results in enhanced presentation of cruzipain peptides to CD4+ T cells from CDP. Purified or serum alpha 2M binds to polymorphic cruzipains, but only a fraction of the proteinases become covalently linked. Once bound to alpha 2M, fluorescein-labeled cruzipain (FITC-cruzipain) or [125I]cruzipain were more efficiently internalized by normal peripheral blood mononuclear cells (PBMC) or monocytes; this effect was abolished by (I) pre-treating the cells with receptor-associated protein (rRAP), a known antagonist the of alpha 2M receptor (alpha 2MR/LRP), and (II) inactivating [125I]cruzipain's active site prior to the reaction with alpha 2M, indicating that the exposure of receptor binding sites on alpha 2M complexes required bait region cleavage. We then sought to determine if the alpha 2MR/LRP-dependent uptake of alpha 2M:cruzipain by monocytes resulted in increased CD4+ T cell responses of PBMC-CDP (n = 13). These effects were only revealed after depletion of CD19+ B lymphocytes from PBMC-CDP; the threshold of T cell stimulation was far lower in cultures stimulated with alpha 2M:cruzipain, as compared to antigen alone. Myocardial specimens from CDP with chronic myocardiopathy (three necropsies) were analyzed by immunohistochemistry with mAb anti-cruzipain or anti-alpha 2MR/LRP (CD81+). Extracellular depots of cruzipain were localized amidst inflammatory mononuclear infiltrates, part of which contained CD91+ macrophage-like cells. Ongoing studies should clarify if T. cruzi cysteinyl proteinases play a role in the pathogenesis of Chagas' heart disease.   相似文献   
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Nephrolithias is a common problem in populations around the world, and contribute significantly to the development of end stage renal disease. It is a matter of debate whether the metabolic factors responsible for renal stone formation are similar or variable in different populations around the globe. This review discusses the influence of different metabolic and dietary factor, and some other co-morbid conditions on the etiopathogenesis Nephrolithiasis. Evaluation and medical management of Nephrolithiasis is summarized in the later part of the article.  相似文献   
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In the month of Ramadan, patients with thyroid diseases, most of the time, do not need treatment adjustments and can fast safely without any health hazards. Patients with hypothyroidism taking thyroxine can take their tablets on an empty stomach at bedtime instead of half an hour before Sehr. Patients with hyperthyroidism, on methimazole/carbimazole can continue their dose in once or twice daily regimes, while those on propylthiouracil need to be switched. Hyperthyroid patients with severe symptoms should start treatment immediately and can avoid fast for few days after a consultation with their religious scholar.  相似文献   
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Data on the distribution of beta thalassemia among over 6,000 Melanesians reveals a major difference in the carrier rates between populations in the malarious coastal regions of New Guinea and those living in the historically malaria-free Highlands. The island of Maewo in Vanuatu has a particularly high incidence of beta + thalassemia associated with a single restriction enzyme haplotype. Direct cloning into a plasmid vector and sequence analysis demonstrate that the mutation is a G to C transversion at position 5 of intron 1 of the beta- globin gene. Oligonucleotide probe surveys indicate that this variant accounted for all cases of beta thalassemia studied from Maewo. It is also common in coastal Papua New Guinea where haplotype and oligonucleotide probe data suggest that the molecular basis of beta thalassmia is more heterogeneous.  相似文献   
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