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排序方式: 共有307条查询结果,搜索用时 31 毫秒
41.
The aim of our study was to investigate the coexistence of thyroid autoimmunity and allergic diseases. The prevalence of thyroid autoantibodies was studied in sera from 140 children with different kinds of allergic diseases, 370 11-13-y-old schoolchildren without allergic diseases serving as controls. The prevalence of thyroid peroxidase autoantibodies was found to be higher among the patients than in the control group, 11.4% vs 5.4% (p < 0.05). Ultrasound investigation identified autoimmune thyroiditis in 4.3% (6/140) of the series, which was later confirmed with fine needle aspiration in all six cases, four of which were unknown prior to the study. Our findings may be useful to alert clinicians that thyroid diseases may be superimposed on allergic children. 相似文献
42.
Shank Erik J.; Seitz Patricia K.; Bubar Marcy J.; Stutz Sonja J.; Cunningham Kathryn A. 《Canadian Metallurgical Quarterly》2007,121(6):1224
γ-aminobutyric acid (GABA) neurons in the ventral tegmental area (VTA) provide innervation to cortical and subcortical regions of the brain. To solidify the importance of these VTA GABA neurons in behavioral function, we employed the neurotoxin dermorphin-saporin (DS) to selectively lesion VTA GABA neurons prior to assessing spontaneous motor activity. Rats were bilaterally microinfused with DS (1.0 or 2.0 pmol/200 nl/side) or blank-saporin control (BS, 200 nl/side) into the VTA. Seven days later, DS-treated rats exhibited significantly elevated motility in comparison with BS-treated rats; this elevated motility normalized by Day 14 following pretreatment with 1.0 pmol of DS but was sustained on Day 14 after pretreatment with 2.0 pmol of DS. A selective loss of VTA GABA neurons on Day 14 was demonstrated through reduced expression of mRNA for glutamic acid decarboxylase-67 and μ-opioid receptor, but not tyrosine hydroxylase (a dopamine neuron marker), in the VTA. Thus, a dose- and time-related selective loss of VTA GABA neurons was accomplished using this novel neurotoxin. This loss of GABA VTA neurons was associated with hypermotility, further supporting their important regulatory role in the generation of behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
MR imaging and localized proton MR spectroscopy in late infantile neuronal ceroid lipofuscinosis 总被引:1,自引:0,他引:1
D Seitz W Grodd A Schwab U Seeger U Klose T N?gele 《Canadian Metallurgical Quarterly》1998,19(7):1373-1377
PURPOSE: Late juvenile neuronal ceroid lipofuscinosis (NCL) is a lysosomal neurodegenerative disorder caused by the accumulation of lipopigment in neurons. Our purpose was to characterize the MR imaging and spectroscopic findings in three children with late infantile NCL. METHODS: Three children with late infantile NCL and three age-matched control subjects were examined by MR imaging and by localized MR spectroscopy using echo times of 135 and 5. Normalized peak integral values were calculated for N-acetylaspartate (NAA), choline, creatine, myo-inositol, and glutamate/glutamine. RESULTS: MR imaging revealed volume loss of the CNS, most prominently in the cerebellum. The T2-weighted images showed a hypointense thalamus and hyperintense periventricular white matter. Proton MR spectra revealed progressive changes, with a reduction of NAA and an increase of myo-inositol and glutamate/glutamine. In long-standing late infantile NCL, myo-inositol became the most prominent resonance. Lactate was not detectable. CONCLUSION: MR imaging in combination with proton MR spectroscopy can facilitate the diagnosis of late infantile NCL and help to differentiate NCL from other neurometabolic disorders, such as mitochondrial or peroxisomal encephalopathies. 相似文献
44.
In Bacteria and Eukarya, ssDNA-binding proteins are central to most aspects of DNA metabolism. Until recently, however, no counterpart of an ssDNA-binding protein had been identified in the third domain of life, Archaea. Here, we report the discovery of a novel type of ssDNA-binding protein in the genomes of several archaeons. These proteins, in contrast to all known members of this protein family, possess four conserved DNA-binding sites within a single polypeptide or, in one case, two polypeptides. This peculiar structural organization allows us to propose a model for the evolution of this class of proteins. 相似文献
45.
G Wunderlich U Knorr H Herzog JC Kiwit HJ Freund RJ Seitz 《Canadian Metallurgical Quarterly》1998,42(1):18-26; discussion 26-7
OBJECTIVE: Low-grade brain tumors may remain asymptomatic in contrast to malignant gliomas. The mechanisms underlying the preservation of cerebral function in such gliomas are not well understood. METHODS: We used positron emission tomography and transcranial magnetic stimulation for presurgical monitoring of motor hand function in six patients with gliomas of the precentral gyrus. All patients were able to perform finger movements of the contralesional hand. RESULTS: Movement-related increases of the regional cerebral blood flow occurred only outside the tumor in surrounding brain tissue. Compared with the contralateral side, these activations were shifted by 20 +/- 13 mm (standard deviation) within the dorsoventral dimension of the precentral gyrus. This shift of cortical hand representation could not be explained by the deformation of the central sulcus as determined from the spatially aligned magnetic resonance images but was closely related to the location of the maximal tumor growth. Dorsal tumor growth resulted in ventral displacement of motor hand representation, leaving the motor cortical output system unaffected, whereas ventral tumor growth leading to dorsal displacement of motor hand representation compromised the motor cortical output, as evident from transcranial magnetic stimulation. In two patients, additional activation of the supplementary motor area was present. CONCLUSION: Our data provide evidence for the reorganization of the human motor cortex to allow for preserved hand function in Grade II astrocytomas. 相似文献
46.
DR Smith P Richterich M Rubenfield PW Rice C Butler HM Lee S Kirst K Gundersen K Abendschan Q Xu M Chung C Deloughery T Aldredge J Maher R Lundstrom C Tulig K Falls J Imrich D Torrey M Engelstein G Breton D Madan R Nietupski B Seitz S Connelly S McDougall H Safer R Gibson L Doucette-Stamm K Eiglmeier S Bergh ST Cole K Robison L Richterich J Johnson GM Church JI Mao 《Canadian Metallurgical Quarterly》1997,7(8):802-819
The nucleotide sequence of 1.5 Mb of genomic DNA from Mycobacterium leprae was determined using computer-assisted multiplex sequencing technology. This brings the 2.8-Mb M. leprae genome sequence to approximately 66% completion. The sequences, derived from 43 recombinant cosmids, contain 1046 putative protein-coding genes, 44 repetitive regions, 3 tRNAs, and 15 tRNAs. The gene density of one per 1.4 kb is slightly lower than that of Mycoplasma (1.2 kb). Of the protein coding genes, 44% have significant matches to genes with well-defined functions. Comparison of 1157 M. leprae and 1564 Mycobacterium tuberculosis proteins shows a complex mosaic of homologous genomic blocks with up to 22 adjacent proteins in conserved map order. Matches to known enzymatic, antigenic, membrane, cell wall, cell division, multidrug resistance, and virulence proteins suggest therapeutic and vaccine targets. Unusual features of the M. leprae genome include large polyketide synthase (pks) operons, inteins, and highly fragmented pseudogenes. 相似文献
47.
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49.
A myasthenic reaction developed after an average latency of seven to eight months in 12 female patients (average age 51 years) treated with penicillamine for chronic rheumatoid arthritis. In most of them only the purely ocular form was noted, but generalisation of various degrees also occurred. When penicillamine had been discontinued the myasthenic signs were almost always fully reversible, recurring once again when treatment with penicillamine was started. In some instances a transitory symptomatic treatment with cholinesterase inhibitors was necessary. The occurrence of the myasthenic signs in these circumstances is probably similar to the anti-basal membrane nephropathy induced by penicillamine. 相似文献
50.
Examined imitative recall for sentences conforming to the grammatical rules of standard English vs those suggested for nonstandard (black) English. Ss were a total of 87 black and 51 white low- and middle-income children in Grades 3 and 4. Low-income blacks showed better recall than middle-income whites for nonstandard sentences and poorer recall for standard sentences. School integration influenced the performance of low-income blacks: Those who had attended an integrated school were both better on standard and poorer on nonstandard sentences than those who had attended a segregated school. For middle-income Ss, both black and white, there were no evident linguistic effects of integration. Although dialect clearly affected recall, results do not support a conception of black dialect as a separate linguistic system with totally consistent rules. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献