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51.
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Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease.  相似文献   
53.
Although magnetic resonance imaging (MRI) is a valuable aid in the initial diagnosis of multiple sclerosis (MS), quantitatively MRI has been disappointing in staging and evaluating therapy protocols by means of serial examinations. In this study, image processing algorithms were developed for the global analysis of MR images of the cerebrum. Limited three-dimensional segmentation was achieved through histogram analysis by these algorithms, which are essentially operator independent. The effects of coil response and tip angles, patient positioning, and interslice gap thicknesses were examined for 10 MS patients with repeated examinations for a total of 72 images. Effects of technique and instrumentation errors were approximately 6%, and agreement between two independent operators for measuring the total MR pixel sum from periventricular effusions and intense MS plaques was better than 97% with a standard deviation of 2.9%.  相似文献   
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Fifty-eight patients with severe thoracolumbar burst fractures were treated with bilateral transpedicular decompression, Harrington rod instrumentation, and spine fusion. Spinal realignment and stabilization was achieved by contoured dual Harrington distraction rods supplemented by segmental sublaminal wiring. Posterior element fractures were noted in 25 patients, 9 of whom had associated dural tears. Computed tomography was performed to assess the cross-sectional area of the spinal canal before surgery and after decompression. Patients at initial evaluation averaged greater than 67% spinal canal compromise. After surgery, successful decompression was accomplished in 57 patients. One patient required staged, anterior thoracoabdominal decompression and fibula strut grafting. At follow-up (average, 43 months; range, 25-70 months), neurologic improvement was found in 77% of the patients who initially presented with neurologic deficits. Thirty-four of 40 patients with incomplete paraplegia improved one or more subgroups on the Frankel scale. A solid fusion was attained in all 58 patients. No patient had a significant residual kyphotic deformity. Single-stage bilateral transpedicular decompression and dual Harrington rod instrumentation reliably provides decompression of the spinal canal and restores spinal alignment. The procedure allows early mobilization and provides an environment for solid fusion and maximum neurologic return.  相似文献   
56.
We describe a patient with severe combined immunodeficiency and transplacental transfer of maternal T cells who received an unfractionated HLA-identical sibling bone marrow transplant without prior conditioning. He presented prior to transplantation with a dermatitis later diagnosed as mild graft versus host disease. He had a normal absolute lymphocyte count, but proliferative responses to mitogens were very low. Antigens of the noninherited maternal HLA haplotype were detected on his blood lymphocytes. After transplantation, he developed a severe reaction including fever, cutaneous erythema and hepatosplenomegaly. Lymphocytes carrying the noninherited maternal HLA haplotype disappeared from his circulation, and his unprimed mononuclear cells became spontaneously cytotoxic to maternal lymphoblasts. He subsequently developed a lymphocytosis of 69,000/mm3, diarrhea, elevated transaminases and a worsening rash, necessitating treatment with immunosuppressive agents. Full T-cell engraftment and evidence of B-cell function later ensued and spontaneously cytotoxic lymphocytes against maternal cells disappeared by 47 days post-transplantation. We postulate that the patient's constellation of signs and symptoms after transplantation represented a combination of severe graft versus graft and mild graft versus host reactions.  相似文献   
57.
Evolution of Vascular Access   总被引:1,自引:0,他引:1  
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58.
Topical application of the H2-histamine receptor agonist, dimaprit (S-[4-N,N-dimethylaminopropyl]isothiourea), produced eosinophil chemotaxis into the anterior segment of rabbit eyes only when an H2-antagonist was co-administered. Nordimaprit (S-[4-N,N-dimethylaminoethyl]isothiourea), a structural homologue of dimaprit that lacked activity at histamine receptors, produced eosinophil chemotaxis whether or not an H2-antagonist was co-administered. Onset of eosinophil chemotaxis began after 2 or more days of treatment, and was accompanied by corneal edema, opacification, and ocular inflammation. There was no concurrent eosinophilia in the peripheral blood or in the conjunctiva. The response occurred in pigmented and albino rabbit eyes, and was facilitated by prior co-administration of proparacaine eye drops. Another dimaprit homologue without activity at histamine receptors, homodimaprit (S-[4-N,N-dimethylaminobutyl]isothiourea), did not produce eosinophil chemotaxis when applied topically, nor did the H2-agonists impromidine, histamine, or 4-methylhistamine, whether co-administered with an H2-antagonist or not. It was concluded that dimaprit and nordimaprit produced a selective eosinophil chemotaxis unrelated to H1- and H2-histamine receptor activity. However, the H2-agonist activity of dimaprit appeared to inhibit this response unless neutralized by an H2-antagonist. Topical application of dimaprit with an H2-antagonist or nordimaprit alone may allow large numbers of non-degranulated eosinophils, free of other cell types, to be harvested from the aqueous humor.  相似文献   
59.
We have compared levels of albumin and serum amino acids in a group of 87 recent admissions to a nursing home, average age 83 years, with a group of healthy moderately old subjects, average age 69 years. We found that the nursing home group was characterized by decreased levels of albumin, by increased total levels of the measured amino acids, and by increased levels of the nonessential amino acids. In contrast, there were no significant group differences in the essential amino acids. Among the nursing home patients, there was a negative correlation between essential amino acids and disability, consistent with nutritional deficits in the more disabled patients, and a positive correlation between essential amino acids and subjective complaints of pain, suggesting that pain is associated with breakdown or mobilization of endogenous protein stores. Though the nursing home patients had decreased serum levels of tryptophan, there was no association between serum tryptophan or other variables that could be related to the availability of tryptophan for transport into brain, with ratings of either depression or pain. Glutamine levels were significantly increased in the nursing home residents, and among these patients they were positively correlated with measures of cognitive impairment.  相似文献   
60.
The prenatal and/or postweaning effects of a hypertensinogenic high NaCl-containing diet (8.0% NaCl, w/w) on (1) the regional distribution of alpha 1-adrenoceptors and muscarinic cholinergic receptor sites in the heart and (2) the predisposition/resistance to hypertension (HT) were assessed in the inbred Dahl HT-sensitive (S/JR) and HT-resistant (R/JR) rat. The density of alpha 1-adrenoceptors was reduced in the left ventricle but not consistently affected in the ventricular septum, right ventricle, or atria of S/JR offspring with NaCl-induced HT. Both normotensive and hypertensive S/JR rats also displayed a significantly greater density of cholinergic receptor sites in the atria but few consistent alterations in other regions of the heart, compared to R/JR rats. Maternal diet had no effect on the predisposition/resistance to salt-induced HT and little effect on the regional development of alpha 1-adrenoceptors and cholinergic receptor sites. The results of this study suggest that the reduced density of ventricular alpha 1-adrenoceptors in the S/JR strain is a consequence of HT while the elevated density of cholinergic receptors in the atria may be related to the genetic predisposition/resistance to HT.  相似文献   
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