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排序方式: 共有7572条查询结果,搜索用时 15 毫秒
991.
992.
H Kristen G Lukeschitsch F Plattner R Sigmund P Resch 《Prosthetics and orthotics international》1984,8(2):76-81
Exact differentiation into stump and phantom pain is required when pain is reported after amputation. In a majority of cases appropriate treatment can improve the pain. Thermography is simple and gives a good indication of the circulation in the stump without operative intervention. It provides a key to the nature of the pain in stump and phantom. Although typical patterns occur for pain in the stump or phantom, in this study the thermographic image could confirm the presence of phantom pain, but it could not rule out errors or false statements. 相似文献
993.
994.
W. H. Dantzler Kristen K. Evans Stephen H. Wright 《Pflügers Archiv : European journal of physiology》1998,436(6):899-905
Choline can undergo both net secretion and net reabsorption by renal proximal tubules, but at physiological plasma levels
net reabsorption occurs. During this process, choline enters the cells at the luminal side down an electrochemical gradient
via a specific transporter with a high affinity for choline. It appeared likely that choline was then transported out of the
cells against an electrochemical gradient at the basolateral membrane by countertransport for another organic cation. This
possibility was examined by studying net transepithelial reabsorption and basolateral uptake and efflux of [14C]choline in isolated S2 segments of rabbit renal proximal tubules. Basolateral uptake, which was inhibited by other organic
cations such as tetraethylammonium (TEA), appeared to occur by the standard organic cation transport pathway. However, the
addition of TEA to the bathing medium not only failed to trans-stimulate net transepithelial reabsorption and basolateral efflux of [14C]choline but it actually inhibited transepithelial reabsorption by @60%. The results do not support the presence of a countertransport
step for choline against an electrochemical gradient at the basolateral membrane. Instead, they suggest that choline crosses
this membrane by some form of carrier-mediated diffusion even during the reabsorptive process.
Received: 24 March 1998 / Received after Revision: 15 June 1998 / Accepted: 2 July 1998 相似文献
995.
In vitro and in vivo Activities of Different Immunoglobulin G Preparations from the Rabbit against Enterobacteriaceae 总被引:1,自引:0,他引:1
M. Trautmann Y. Müller-Leutloff T. Hofstaetter F.R. Seiler and H. Hahn 《Vox sanguinis》1985,49(4):267-276
Specific rabbit IgG, prepared against three enterobacterial strains, was modified according to procedures used for the production of human IgG preparations suitable for intravenous infusion. The resulting products were examined for their in vitro opsonic and in vivo protective activity against the respective bacterial strains. A sulfonated IgG preparation (S-sIgG) and the enzymatically derived fragments F(ab')2 and Fab/Fc were opsonic in vitro and provided in vivo protection against lethal enterobacterial infection in mice. Protection by Fab fragments varied in the different in vivo models. 相似文献
996.
S-sulfonation represents a reversible chemical modification of disulfide bonds by which under the special conditions chosen only about 2.2 cystine units per IgG molecule are cleaved. Physicochemical and functional evidence for reconstitution is presented. Molecules reconstituted in vitro or in vivo regain, within a few hours, a reactivity (antigen binding, immunoprecipitation, Clq-mediated cross-linking of immune complexes) comparable to equimolar control preparations. 相似文献
997.
998.
B Wüst H B St?helin W O Seiler 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1990,60(1):19-25
The supplementation of an enteral feeding formula on soya-basis specially designed for geriatric patients with 1,5 mg to 2 mg beta-carotene per day increases its corresponding plasmatic concentration from 20 mcg/L to normal to optimal levels near 500 mcg/L. This intake is much lower than the proposed safe intake of 6-20 mg beta-carotene per day. A close incorporation of beta-carotene in the lipid moiety of the ready-to-use formula might increase its bioavailability. The other anti-oxidative vitamins A and E remain to their respective normal levels at a supplemental daily intake of 2500 IU vitamin A and 12,5 mg vitamin E. The new enteral feeding formula for geriatric patients seems to cover their global nutritional needs. 相似文献
999.
Per-Erik Engstöm ers Larsson Gunilla Norhagen C.I. Edvard Smith Matti Sällberg Kristen Helgeland Lennart Hammarström 《Journal of clinical periodontology》1993,20(10):746-751
Abstract Salivary and gingival crevicular fluid antibodies and systemic antibodies were analysed for levels and specificity against Actinobacillus actinomycetemcomitans components. The major reactivity of salivary and serum IgA1 and IgA2 antibodies to the periodontal pathogen A. actinomycetemcomitans was against bands between 14 and 83 kD for IgA1 and bands between 14 and 68 kD for IgA2 in Western blot. In addition to specific binding, there was also a hitherto unrecognized Fc-mediated binding of IgG antibodies to an A. actinomycetemcomitans component around 50 kD. Serum IgG antibodies to A. actinomycetemcomitans leukotoxin displayed the highest median value and only 1 individual showed salivary IgM antibodies in ELISA. Elevated levels of gingival crevicular fluid lgA2 antibodies indicated a local production of IgA from periodontal tissues. Using synthetic peptides, several distinct epitopes on the leukotoxin were recognized by both salivary and serum IgA antibodies. 相似文献
1000.
Mathematical error analysis shows that the prognosis of IOL powers on the basis of theoretical optical formulas for calculating lens power is no more accurate than the regression (SRK) formula. The minimum error in a recommended lens power is at present between +/- 0.6 and +/- 1.0 D. As a result of this range of error there is a range of equivalence of the two formulas, and the vast majority of cataract patients (85%) are within this range. However, in hyperopic eyes the SRK formula is clearly superior to the theoretical optical formulas for a clinically useful prognosis. 相似文献