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21.
Previously, we showed that the N-terminal recognition domain (T1) of Kv1.3 was not required for assembly of functional channels [Tu et al. (1996) J. Biol. Chem. 271, 18904-18911]. Moreover, specific Kv1.3 peptide fragments including regions of the central core are able to inhibit expression of current produced from a channel lacking the T1 domain, Kv1.3(T1-). To elucidate the mechanism whereby Kv1.3 peptide fragments suppress Kv1.3(T1-) current, we have studied the ability of peptide fragments containing the transmembrane segments S1, S1-S2, or S1-S2-S3 to physically associate with the Kv1.3(T1-) polypeptide subunit in vitro in microsomal membranes. Using c-myc (9E10) epitope-labeled peptide fragments and anti-myc antibody as well as antisera to the Kv1.3 C-terminus, we now demonstrate specific association of these peptide fragments with Kv1.3(T1-). Association of peptide fragments with Kv1.3(T1-) was correlated with integration of both proteins into the membrane. Furthermore, the relative strength and kinetics of this association directly correlated with the ability of fragments to suppress Kv1.3(T1-) current. The rate-limiting step in the sequential synthesis, integration, and formation of a complex was the association of integrated polypeptides within the plane of the lipid bilayer. These results strongly suggest that the physical association of transmembrane segments provides the basis for suppression of K+ channel function by K+ channel peptide fragments in vivo. Moreover, the S1-S2-S3 peptide fragment potently suppressed full-length Kv1.3, thus implicating a role for the S1-S2-S3 region of Kv1.3 in the assembly of the Kv1.3 channel. We refer to these putative association sites as IMA (intramembrane association) sites.  相似文献   
22.
Reports an error in "What can we learn from the morphology of Hebrew? A masked-priming investigation of morphological representation" by Ram Frost, Kenneth I. Forster and Avital Deutsch (Journal of Experimental Psychology: Learning, Memory, and Cognition, 1997[Jul], Vol 23[4], 829-856). On page 854, two Hebrew words are missing from Appendix F. The corrected Appendix appears with the erratum. (The following abstract of the original article appeared in record 1997-05320-003.) All Hebrew words are composed of 2 interwoven morphemes: a triconsonantal root and a phonological word pattern. The lexical representations of these morphemic units were examined using masked priming. When primes and targets shared an identical word pattern, neither lexical decision nor naming of targets was facilitated. In contrast, root primes facilitated both lexical decisions and naming of target words that were derived from these roots. This priming effect proved to be independent of meaning similarity because no priming effects were found when primes and targets were semantically but not morphologically related. These results suggest that Hebrew roots are lexical units whereas word patterns are not. A working model of lexical organization in Hebrew is offered on the basis of these results. (A correction concerning this article appears in Journal of Experimental Psychology: Learning, Memory, and Cognition, 1997, Vol 23(5), 1189-1191. On page 854 of the current issue, two Hebrew words are missing from Appendix F. The corrected Appendix appears in this correction.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
From 25 to 27 Sept 1997, a workshop was organized at the Essen Medical School (Universit?tsklinikum Essen), at which radiooncologists and jurists from universities and courts as well as lawyers contributed their views on mutual problems. The following topics were discussed by papers and in round table meetings: "Requirements on the patient's information", "definition of therapeutic guidelines-limits of clinical research and standard treatments", "treatment documentation", "liability of the physician for treatment faults" and "technical standard and preserve of quality". The consensual guidelines to the topics "patient's information", "therapeutic guidelines" and "liability" are presented here.  相似文献   
24.
OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included.  相似文献   
25.
Pulsed photothermal radiometry (PPTR) has been used to measure, in vitro, the optical attenuation coefficients of normal and diseased human artery at four wavelengths (308, 351, 488, 532 nm) in the near UV and visible spectrum. The advantages and limitations of this noncontact method of measuring the optical properties of biological material, as well as other potential applications, are discussed.  相似文献   
26.
Single-pass gain has been measured for flowing CO2, CO2-N2, CO2-He, CO2-N2-He, and CO2-N2-H2mixes. The gain for CO2-N2mixes varies as d-0.9, wheredis the tube diameter. The diameter dependence of the gain is less pronounced for CO2- N2-He mixes; a peak gain of 4.7 dB/m was obtained in a 1/2 in diam tube. Fluorescence data indicate that the upper laser level population is saturated at 100 mA in all cases. The addition of He, H2, or O2depopulates the lower laser level; helium further increases the population of the upper laser level. The addition of CO increases the population of the upper laser level, probably by resonant transfer from the excited vibrational states of CO.  相似文献   
27.
The objective of this case study is to provide insight to practitioners about the methodology of using the space-time autoregressive integrated moving average (STARIMA) class of models to formulate stochastic demand of the transportation problem. While providing insight, two other methods-expected value (EV) and stochastic approximation (SA)-are also employed to formulate demand. A comparative evaluation of the methods using brewery data for the distribution of four products from five production plants to 64 distribution centers is presented. It is shown that the demand characterized by the STARIMA approach results in a lower total cost of transportation. This occurs because the STARIMA approach results in better forecasts. Based upon the case study, the cost analysis indicated that the STARIMA method when used without (with) updating resulted in a 9.49% (10.5%) increase in the Company's net profit as compared with the SA method. Similarly, the STARIMA approach when used without (with) updating resulted in an 11.36% (12.37%) increase in the net profit as compared with the EV method. For the STARIMA approach, computations for a large size problem are shown to be identical to those of the deterministic transportation problem given the demand forecasts. Extra computation effort for producing STARIMA forecasts are easily justified in terms of the increased profit margin  相似文献   
28.
This paper compares the major classes of chip-to-chip and on-chips interconnections used in high-performance computers and communication systems and reviews their electrical characteristics. Measurement results of dielectric loss are shown and the attenuation is compared for printed-circuit-board, glass-ceramic, thin-film, and on-chip wiring. Simulation results are shown with representative driver and receiver circuits, guidelines are given for when losses are significant, and predictions are made for the sustainable bandwidths on useful wiring lengths  相似文献   
29.
Tested the relationship between popularity and communicative egocentrism with female preschoolers, and assessed the relationship between communicative egocentrism and 2 popularity measures: (a) a realistic measure of actual classroom interaction and (b) a sociometric measure of preferred playmates. Ss were 60 white middle-class 3-5 yr old female preschoolers. Results indicate that communicative egocentrism was significantly related to the observational measure of peer popularity even when the common effect of IQ was removed. Communicative egocentrism, however, was not significantly related to the sociometric measure of popularity. The possibility of a curvilinear relationship existing between communicative egocentrism and a sociometric measure of popularity is advanced. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
30.
Investigated the syntactic priming effect and the involvement of attention in that process by testing identification of white noise-masked Hebrew words. Targets were either syntactically congruent or syntactically incongruent with the structure of the sentence. Relative to a neutral condition, similar facilitation and inhibition was found for congruent and incongruent targets, respectively. When syntactic congruency was blocked, the inhibition was attenuated, whereas the facilitation remained the same. A 350-msec silent interstimulus interval between context and target increased inhibition without affecting facilitation. It is suggested that both the facilitation and the inhibition effects of syntactic priming are based on a veiled controlled process of generating expectations. The inhibition results from a controlled process of reevaluation that requires additional attention resources. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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