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31.
Sensory integration (SI) therapy is a controversial--though popular--treatment for the remediation of motor and academic problems. It has been applied primarily to children with learning disabilities, under the assumption that such children (or at least a subgroup of them) have problems in sensory integration to which some or all of their learning difficulties can be ascribed. The present article critically examines the related issues of whether children with learning disabilities differentially exhibit concomitant problems in sensory integration, and whether such children are helped in any way by means specific to SI therapy. An overview of theoretical contentions and empirical findings pertaining to the first issue is presented, followed by a detailed review of recent studies in the SI therapy research literature, in an effort to resolve the second issue. Results of this critique raise serious doubts as to the validity or utility of SI therapy as an appropriate, indicated treatment for the clinical population in question--and, by extension, for any other groups diagnosed as having "sensory integrative dysfunction." It is concluded that the current fund of research findings may well be sufficient to declare SI therapy not merely an unproven, but a demonstrably ineffective, primary or adjunctive remedial treatment for learning disabilities and other disorders.  相似文献   
32.
We study one weight \(\mathbb {Z}_2\mathbb {Z}_4\) additive codes. It is shown that the image of an equidistant \(\mathbb {Z}_2\mathbb {Z}_4\) code is a binary equidistant code and that the image of a one weight \(\mathbb {Z}_2\mathbb {Z}_4\) additive code, with nontrivial binary part, is a linear binary one weight code. The structure and possible weights for all one weight \(\mathbb {Z}_2\mathbb {Z}_4\) additive codes are described. Additionally, a lower bound for the minimum distance of dual codes of one weight additive codes is obtained.  相似文献   
33.
Peptide toxins have proved to be useful agents, both in discriminating between different components of native calcium channel currents and in the molecular isolation and designation of their cloned channel counterparts. Here, we describe the isolation and characterization of the biochemical and physiological properties of a novel 74-amino acid peptide toxin (DW13.3) extracted from the venom of the spider Filistata hibernalis. The subtype specificity of DW13.3 was investigated using calcium channel currents recorded from two separate expression systems and several different cultured mammalian cell preparations. Overall, DW13.3 potently blocked all native calcium channel currents studied, with the exception of T-type currents recorded from GH3 cells. Examination of transiently expressed calcium channels in oocytes showed that DW13.3 had the highest affinity for alpha1A, followed by alpha1B > alpha1C > alpha1E. The affinity of DW13.3 for alpha1B N-type currents varied by 10-fold between expressed channels and native currents. Although block occurred in a similar 1:1 manner for all subtypes, DW13.3 produced a partial block of both alpha1A currents and P-type currents in cerebellar Purkinje cells. Selective occlusion of the P/Q-type channel ligand omega-conotoxin MVIIC (but not omega-agatoxin IVA) from its binding site in Purkinje neurons suggests that DW13.3 binds to a site close to the pore of the channel. The inhibition of different subtypes of calcium channels by DW13.3 reflects a common "macro" binding site present on all calcium channels except T-type.  相似文献   
34.
Mesangial cells (MC) of renal glomeruli respond to immune-inflammatory injury by accelerated proliferation and generation of reactive oxygen metabolites (ROM). We studied in vivo and in vitro roles of cAMP-protein kinase A (PKA) signaling in modulation of these pathobiologic processes with focus on PDE isozymes. Mitogenic synthesis of DNA in mesangial cells grown in primary culture was blocked by forskolin and dibutyryl cyAMP. Incubation of MC with PDE-3 inhibitors, cilostamide and lixazinone, inhibited (> 50%) mitogenesis, whereas inhibitors of PDE-4, rolipram and denbufylline, caused little or no inhibition. Conversely, inhibitors of PDE-4 suppressed generation of ROM in MC, whereas inhibitors of PDE-3 had no effect. Incubation of mesangial cells with cilostamide or with rolipram increased in situ activity of PKA, and effects of the two inhibitors were additive. PDE inhibitors also decreased activity of mitogen-activated protein kinase. The efficacy of PDE isozyme inhibitors (IC50) to suppress mitogenesis or ROM generation paralleled IC50 for inhibition of cAMP hydrolysis by extracts from mesangial cells. Administration of lixazinone or lixazinone in combination with rolipram to rats with mesangial proliferative glomerulonephritis induced by antithymic serum suppressed proliferation of mesangial cells and also reduced other histopathologic manifestations of the disease. Based on these observations, we propose that in MC, a cAMP pool that is hydrolyzed by PDE-3 inhibits by negative crosstalk via activation of PKA, mitogen-activated protein kinase (MAPK) pathway, and mitogenesis; whereas cAMP pool linked to PDE-4 inhibits, also via activation of PKA, ROM generation in mesangial cells. Results also suggest that PDE isozyme inhibitors, in particular inhibitors of PDE-3, should be investigated for potential use for "signal transduction pharmacotherapy" of glomerulonephritis.  相似文献   
35.
RATIONALE AND OBJECTIVES: A thrombus-specific ultrasound contrast agent, MRX-408, has been developed recently. This agent consists of phospholipid-coated microbubbles with a ligand capable of targeting the GPIIb/IIIa receptor, thereby allowing the microbubbles to bind with thrombi rich in activated platelets. In vitro and in vivo animal experiments have been conducted to examine imaging enhancement and sonothrombolysis using this agent compared with a nontargeted agent. METHODS: For clot binding, blood-smeared slides were incubated with microbubbles and examined under a light microscope. Change in backscatter signals from the blood clots after binding was examined by both an ultrasound scanner and two single-element transducers arranged in a transmitter-receiver pair. For clot lysis, either 1-MHz or 20-KHz ultrasound was used to enhance the lysing effects of MRX-408 with or without urokinase. RESULTS: Evidence of binding was demonstrated under a microscope. In vitro experiments showed that the "acoustic signature", or properties, of blood clots changed after binding. Clots became more echogenic and nonlinear. In vivo fundamental ultrasound imaging confirmed that as a result of binding, blood clots were more visible, the area of detection was improved, and shadowing behind clots was more noticeable. Under 1-MHz ultrasound and 30 minutes of treatment, lysis efficiency reached 34% with MRX-408, whereas there was no visible clot lysis with saline. CONCLUSION: The results of these preliminary studies show that as a contrast agent, MRX-408 enhanced clots under ultrasound imaging and facilitated sonothrombolysis with or without thrombolytic drugs.  相似文献   
36.
Beidler's work in the 1950s showed that anions can strongly influence gustatory responses to sodium salts. We have demonstrated "anion inhibition" in the hamster by showing that the chorda tympani nerve responds more strongly to NaCl than to Na acetate over a wide range of concentrations. Iontophoretic presentation of Cl- and acetate to the anterior tongue elicited no response in the chorda tympani, suggesting that these anions are not directly stimulatory. Drugs (0.01, 1.0, and 100 microM anthracene-9-carboxylate, diphenylamine-2-carboxylate, 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonate, and furosemide) that interfere with movements of Cl- across epithelial cells were ineffective in altering chorda tympani responses to 0.03 M of either NaCl or Na acetate. Anion inhibition related to movements of anions across epithelial membranes therefore seems unlikely. The chorda tympani contains a population of nerve fibers highly selective for Na+ (N fibers) and another population sensitive to Na+ as well as other salts and acids (H fibers). We found that N fibers respond similarly to NaCl and Na acetate, with spiking activity increasing with increasing stimulus concentration (0.01-1.0 M). H fibers, however, respond more strongly to NaCl than to Na acetate. Furthermore, H fibers increase spiking with increases in NaCl concentration, but generally decrease their responses to increasing concentrations of Na acetate. It appears that anion inhibition applies to taste cells innervated by H fibers but not by N fibers. Taste cells innervated by N fibers use an apical Na+ channel, whereas those innervated by H fibers may use a paracellularly mediated, basolateral site of excitation.  相似文献   
37.
38.
PURPOSE: Patients with active pars planitis have increased levels of a 36 kDa protein (p-36) in their circulation. The current studies were undertaken to determine the primary structure of this protein. METHODS: A degenerate oligonucleotide probe based on the amino terminal sequence of p-36 was used to identify a clone from a human spleen cDNA library. The cDNA insert was subcloned into the EcoR1 site of pUC-19, and both strands were sequenced. Southern blot analysis was used to study the genomic hybridization pattern. p-36 cDNA was subcloned in a pSG5 expression vector, and the construct was used to transfect COS-7 cells. RESULTS: The cDNA sequence contained an open reading frame of 966 base pairs encoding a protein of 322 amino acids, an untranslated region of 322 base pairs, and 2693 base pairs at the 5' and 3' ends, respectively. The deduced amino acid sequence showed 96.8% identity with the carboxy-terminal region of a yeast nucleopore complex protein, nup 100. Southern blot analysis of human genomic DNA revealed a simple hybridization pattern. Transfection of p-36 cDNA in COS-7 cells resulted in the presence of p-36 mRNA and expression of protein. CONCLUSIONS: The 36 kDa protein (p-36) detected at increased levels in the blood of patients with active pars planitis was cloned from a human spleen cDNA library. Its deduced amino acid sequence is homologous with the carboxy-terminal region of a nucleopore complex protein. Thus, we refer to this protein as nup36.  相似文献   
39.
ABSTRACT: Lowbush or wild blueberries ( Vaccinium angustifolium Ait.) and soy protein offer many complementary health benefits; thus, combinations of these 2 foods may appeal to health-conscious consumers. Four frozen dessert formulations were prepared with soy protein isolate and different amounts of blueberry concentrate and puree. Fat content (3% or 10%) was adjusted with soybean oil and nondairy creamer. Consumers ( n = 40) from the campus community used a 9-point hedonic scale to assess acceptability. The 10% fat content and 8.6% blueberry concentrate formulation received the highest overall acceptability (6.63, P < 0.05), compared with formulations with 10% fat and 17.2% blueberry concentrate and 3% fat and 12.9% blueberry concentrate. More than 1 /3 of the panelists are trying to increase blueberry consumption, 20% want to increase soy, and 20% want to eat more of both foods. Development of palatable desserts combining lowbush blueberries and soy protein could lead to increased consumption of both healthy ingredients.  相似文献   
40.
We consider the representable equational theory of binary relations, in a language expressing composition, converse, and lattice operations. By working directly with a presentation of relation expressions as graphs we are able to define a notion of reduction which is confluent and strongly normalizing and induces a notion of computable normal form for terms. This notion of reduction thus leads to a computational interpretation of the representable theory.  相似文献   
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