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1.
The action of rotameric probes introduced either in position 7 or 8 in the sequence of substance P (SP) was investigated, i.e. -tetrahydroisoquinoleic acid (Tic), -fluorenylglycine (Flg), -diphenylalanine (Dip), the diastereoisomers of -1-indanylglycine (Ing) and -benz[ƒ]indanylglycine (Bfi), the Z- and E-isomers of dehydrophenylalanine and dehydronaphthylalanine (ΔZPhe, ΔEPhe, ΔZNal, ΔENal) and (Dmp). The aim of this study was the topographical characterization of the binding subsites of human NK-1 receptor expressed in CHO cells, especially the S7 and S8 subsites, corresponding to residues Phe7 and Phe8 of substance P. According to the binding potencies of these substituted-SP analogues, the S7 binding subsite is smaller than the S8 subsite: the S7 subsite accepts only one aromatic nucleus, while the S8 can accommodate three coplanar nuclei altogether. These findings are compatible with the idea that the S8 binding subsite may reside in the extracellular loops of the hNK-1 receptor. NK-1 agonists bind to human NK-1 receptor and activate the production of both inositol phosphates and cyclic AMP. As already quoted for septide, [pGlu6, Pro9]SP(6–11), discrepancies are observed between affinity (Ki) and activity (EC50) values for IPs production. While a weak correlation between Ki and EC50 values for IPs production could be found (r = 0.70), an excellent correlation could be demonstrated between their affinities (Ki) and their potencies (EC50) for cAMP production (r = 0.97). The high potency (EC50) observed for ‘septide-like’ molecules on PI hydrolysis, compared to their affinity is not an artefact related to the high level of NK-1 receptors expressed on CHO cells since a good correlation was found between EC50 values obtained for PI hydrolysis and those measured for spasmogenic activity in guinea pig ileum bioassay (r = 0.94).

According to the binding potencies of constrained analogues of phenylalanine, the S7 binding subsite of human NK-1 receptor is small, whereas the S8, which can accommodate three coplanar nuclei, might probably reside in the extracellular loop. The discrepancies observed between affinity (Ki) and activity (EC50) values for IPs production are not an artefact of CHO cells since a good correlation was found between EC50 for PI hydrolysis and those measured in guinea pig ileum bioassay.  相似文献   

2.
Beginning in the 1960s the first systematic projects dedicated to testing whether great apes could acquire some aspects of human language were conducted. The ape subjects demonstrated remarkable capacities to learn and use elements of either sign language or an artificial language. The results from research across several laboratories drew a mixture of excitement and skepticism, and critiques and debates have ensued since the earliest reports were published. This continues today. Terrace (2019, Nim: A chimpanzee who learned sign language. New York, NY: Columbia University Press) repeats many of the same points made decades earlier, and has added some additional critiques. That scientists hold different perspectives on what to conclude from ape language studies is expected. However, any conclusion one draws should be based upon available evidence, which we outline in this review. We also address the critiques offered by Terrace (2019), including the stance that apes cannot understand or use words. Focusing on symbol use by chimpanzees and bonobos we describe evidence that argues for understanding of words, including capacities for declarative communication and intersubjectivity found in these apes. We conclude that the many decades of research using a variety of symbol systems challenges the absolutist position that chimpanzees and bonobos cannot learn language or understand the concept of a word.  相似文献   
3.
Reports an error in "Contemporary Chinese sex symbols in dreams: Correction to Yu" by Calvin Kai-Ching Yu (Dreaming, 2010[Mar], Vol 20[1], 25-41). The publishing year of the article in the correction notice was listed incorrectly as 2009. The correct publication year for the original article is 2010. The word were was also misspelled in the body of the correction as where. (The following abstract of the original article appeared in record 2010-05656-003.) [Correction Notice: An erratum for this article was reported in Vol 20(2) of Dreaming (see record 2010-12874-005). Three Chinese characters where printed incorrectly in the article. The correct symbols are shown along with the location of each in the original article. An error is also located on page 26, 3rd paragraph from the top, second symbol in the third sentence from the bottom of the paragraph. On page 28, 1st paragraph, the 1st symbol in line 7 of the paragraph is incorrect. The last error is on page 28, in which the 1st paragraph, 1st symbol in the last line of the paragraph is incorrect.] The present study aimed to determine how often Chinese people dream of sexual metaphors and to examine the association between the dreaming of sexual experiences and contemporary Chinese sex symbols. A list of sex symbols was derived from a thorough review of the sexual analogies that Chinese people most often use in slang language. This list, together with the Marlowe-Crowne Social Desirability Scale and the Eysenck Personality Questionnaire Revised–Short Form, was administrated to a sample of 608 upper-secondary school graduates from Hong Kong. It was found that the participants rarely dreamed about food analogies for sex, such as “eating litchis” and “bananas or banana-like objects.” By contrast, sex symbols involving weapons and aggressive behavior, such as “knives, swords, or daggers” and “shooting,” occurred in dreams with moderate prevalence rates. Moreover, gender, the frequency of dreaming sexual experiences, and social desirability significantly predicted the frequency scores on the scale formed by these aggressive symbols for sex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
The static fluid mosaic model of biological membranes has been progressively complemented by a dynamic membrane model that includes phospholipid reordering in domains that are proposed to extend from nanometers to microns. Kinetic models for lipolytic enzymes have only been developed for homogeneous lipid phases. In this work, we develop a generalization of the well-known surface dilution kinetic theory to cases where, in a same lipid phase, both domain and nondomain phases coexist. Our model also allows understanding the changes in enzymatic activity due to a decrease of free substrate concentration when domains are induced by peptides. This lipid reordering and domain dynamics can affect the activity of lipolytic enzymes, and can provide a simple explanation for how basic peptides, with a strong direct interaction with acidic phospholipids (such as beta-amyloid peptide), may cause a complex modulation of the activities of many important enzymes in lipid signaling pathways.  相似文献   
5.
DKP formation is a serious side reaction during the solid‐phase synthesis of peptide acids containing either Pro or Gly at the C‐terminus. This side reaction not only leads to a lower overall yield, but also to the presence in the reaction crude of several deletion peptides lacking the first amino acids. For the preparation of protected peptides using the Fmoc/tBu strategy, the use of a ClTrt‐Cl‐resin with a limited incorporation of the C‐terminal amino acid is the method of choice. The use of resins with higher loading levels leads to more impure peptide crudes. The use of HPLC‐ESMS is a useful method for analysing complex samples, such as those formed when C‐terminal Pro peptides are prepared by non‐optimized solid‐phase strategies. Copyright © 1999 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
6.
The family Trigonalyidae is considered to be one of the most basal lineages in the suborder Apocrita of Hymenoptera. Here, we determine the first complete mitochondrial genome of the Trigonalyidae, from the species Taeniogonalos taihorina (Bischoff, 1914). This mitochondrial genome is 15,927 bp long, with a high A + T-content of 84.60%. It contains all of the 37 typical animal mitochondrial genes and an A + T-rich region. The orders and directions of all genes are different from those of previously reported hymenopteran mitochondrial genomes. Eight tRNA genes, three protein-coding genes and the A + T-rich region were rearranged, with the dominant gene rearrangement events being translocation and local inversion. The arrangements of three tRNA clusters, trnYtrnMtrnItrnQ, trnWtrnL2trnC, and trnHtrnAtrnRtrnNtrnStrnEtrnF, and the position of the cox1 gene, are novel to the Hymenoptera, even the insects. Six long intergenic spacers are present in the genome. The secondary structures of the RNA genes are normal, except for trnS2, in which the D-stem pairing is absent.  相似文献   
7.
8.
Introduction to fish imagery in art   总被引:1,自引:0,他引:1  
Synopsis Fish have been the subject of works of art for at least 14000 years and appeared in primitive art from many cultures. In ancient civilizations of the West, fishes were a constant, if infrequent, motif. Fish designs in ancient Egypt were common and showed little change for 1500 years. Decorative fish designs of the Greeks and Romans (often with mythological significance) were adopted by early Christians as religious symbols. With the development of printing, the non-religious depiction of fish became more widespread and realistic paintings of fish, especially still lifes, appeared during the Renaissance. This still life tradition reached a peak in 17th century Netherlands. After 1750, fish images appeared in many different contexts. Realistic painters showed the agony of newly-caught fish, dramatic marine scenes with fish, and occasionally freshwater fishes in their habitats. In the twentieth century, fish were painted by many modern artists, including Matisse, Picasso, Klee, Masson, Beckman, Soutine, Magritte, and Thiebaud. Some of these artists' fish images are pleasing, others are violent or ambiguously symbolic. In contrast, contemporary nature artists tend to paint live fish in idealized settings, a style with roots in 17th century still lifes and oriental brush paintings. In Japan and China, fish have been an important theme in art and their use has been highly symbolic. A survey of fish images in art shows that artists, like scientists, create mainly in the context of historical precedents.  相似文献   
9.
BACKGROUND: Previous research has noted potential inadequacies in the warning labels and symbols used with some teratogenic medications. A clear teratogen warning symbol represents an important component of risk mitigation for accidental teratogen exposure. METHODS: Several teratogen warning symbols were developed through rapid prototyping and focus groups. A nationally distributed field trial (n = 300) examined the relative effectiveness of 6 candidate symbols, including the symbol in use at the time of the study. Measures included open-ended interpretation, closed-ended preference, and demographic surveys. Each participant was shown a single symbol and asked what it meant, to whom it applied, and what that person should do. Text statements were added to the symbol and participants were asked to reinterpret the warning. Participants were told the intended message of the warning, shown all 6 symbols, and asked to choose the most effective symbol. RESULTS: Four of 6 symbols achieved levels of correct interpretation close to or exceeding the American National Standards Institute (ANSI) benchmark of 85% and none exceeded the ANSI limit of 5% critical confusion. Symbols elicited varying conceptual responses. Respondents considered 1 symbol to be the most effective, by a 4 to 1 margin. Several outcomes varied by age and by ethnicity. CONCLUSIONS: Several symbols emerged as viable alternatives to the current symbol; however, no 1 symbol was clearly found to be the most effective. Instead, the symbol considered "best" depends on the messages that are considered most essential to the warning. Additionally, it appears a symbol without the addition of text can convey most, but possibly not all, of the meaning required of the warning label. Next steps should include further symbol refinement, closer examination of text additions to symbols, and validation of the candidate symbols and warnings through a large-scale field trial.  相似文献   
10.
S L Cohen  P Ho  Y Suzuki  F E Alspector 《Steroids》1978,32(2):279-293
A method is described for purifying the estrogen content of pregnancy urine with little loss of the labile estrogens. The procedure makes use of the initial 50-fold purification effected by their precipitation whith ammonium sulphate, with simultaneous elimination of most urinary corticosteroids and 50--60% of urinary ketosteroids. It also employs the antioxident ascorbic acid as an additive in most stages of the procedure. The mild organic-solvent-HIO partition system of Brown is used for separating the strongly polar, 2including all "labile" estrogens, and of the weakly polar estrogens, from neutral steroids. The remaining neutral steroid still interfering with the assays were removed by an ascorbic acid treated ion exchange resin (AG 1). The final residues were revealed by mass-spectroscopy to consist almost solely of estrogens. Gas-liquid chromatography in which just 2 chromatograms are required yields a total of 12 "estrogen" peaks (for 12 estrogens which are excreted in amounts greater than 0.1 mg/day) in normal pregnancy urine, including all the known labile estrogens. Identification as estrogen for all but a few minor peaks of the gas chromatogram was obtained by mass-spectroscopy. The practical significance of the method lies in the fact that some labile estrogens are much more important in the estrogen metabolism of pregnant and nonpregnant women than heretofore generally thought.  相似文献   
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