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51.
Effects of fatty acid concentration and positional specificity on maize triglyceride structure 总被引:1,自引:0,他引:1
The effects of fatty acid concentration and positional specificity on maize triglyceride structure were evaluated from the
stereospecific analyses of triglycerides from 12 genotypes. The fatty acids at each position were influenced by the fatty
acid concentration in the total triglyceride except for the saturates in the 2 position. The fatty acid concentration had
the greatest effect on the fatty acid composition of position 3. The existence of positional specificity was evident from
the nonrandom distribution of the fatty acids among the three positions of the triglycerides. The concentration and positional
specificity effects could be separated in selected genotypes and their crosses. This indicated different genetic controls
for each effect. 相似文献
52.
30 schizophrenic patients and 30 psychiatric aides were required in 4 experimental tasks to change their responses to meet changing conditions. It was hypothesized that (a) schizophrenic patients are more likely than normals to continue a response after it becomes ineffective; (b) the persistence of the maladaptive response is a function of the severity of schizophrenia. As predicted, the patients persisted longer than the aides in the first learned but later maladaptive responses, and there was some evidence that degree of resistance to change was related to the severity of schizophrenia in the patient. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Kim EY Gronewold C Chatterjee A von der Lieth CW Kliem C Schmauser B Wiessler M Frei E 《Chembiochem : a European journal of chemical biology》2005,6(2):422-431
With the aim of establishing a versatile and easy synthesis of branched saccharides for biological applications, we used molecular-dynamics simulations to model Lewis(y) to two classes of di- or triantennary saccharide mimetics. One set of mimetics was based on 1,3,5-tris(hydroxymethyl)cyclohexane (TMC) as the core, the other on furan, and both were derivatised with galactose and/or fucose. The TMC-based saccharides were biotinylated, while the furan disaccharides were treated with maleimide-activated biotin in a Diels-Alder fashion to yield oxazatricyclodecanes (OTDs). These were then assayed as cell-surface labels in human colon (SW480 and CaCo-2), liver (PLC), Glia (U333 CG 343) and ovary (SKOV-3) tumour cell lines. Discrete staining patterns were observed in all cells, usually at one or two poles of the cells, particularly with the asymmetric 3-beta-L-fucopyranosyloxymethyl-4-beta-D-galactopyranosyloxymethyl-OTD. Normal SV40-transformed fibroblasts (SV80) showed no staining. Adhesion of the highly metastatic mouse melanoma line B16 F10 to fibronectin was inhibited by 80 % by the TMC-digalactoside and by 30 % by 3,4-bis-(beta-D-galactopyranosyloxymethyl)furan. None of the saccharide mimetics inhibited the adhesion of the less metastatic B16 F1 line. Migration of B16 F10 cells through Matrigel was greatly inhibited by the TMC-digalactoside and weakly inhibited by the TMC-trigalactoside. The saccharide mimetics that had shown the best structural agreements with the terminal saccharides of Lewis(y) in the molecular dynamics simulation were also the most biologically potent compounds; this underlines the predictive nature of molecular dynamics simulations. The use of the non-saccharide cores enabled us to adapt spacer lengths and terminal saccharides to optimise the structures to bind more avidly to cell-surface lectins. 相似文献
54.
Presents a fairy tale that illustrates concerns regarding the consequences of the removal of school psychology from the generic house of psychology and the unreality of creating a "separate but equal" nondoctoral profession. Questions of semantic confusion in defining differences between professional psychology and school psychology are raised. It is postulated that the split suggested by J. I. Bardon (see record 1983-24212-001) may result in the extinction rather than the salvation of school psychology. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Evelyn J. Weber 《Lipids》1973,8(5):295-302
Kernels of corn inbred H51 were collected at five intervals after hand pollination. The triglyceride content of the total
lipids increased from 8.6% at 10 days after pollination to 78.3% at 60 days. The most active period of triglyceride synthesis
occurred from 20 to 45 days after pollination, when the weight of triglycerides per kernel increased from 1.1 to 7.5 mg. Over
all the collection periods the percentages of palmitic, linoleic and linolenic acids decreased while oleic acid increased,
but from 30 to 60 days after pollination the fatty acid composition of the triglycerides was nearly constant. Stereospecific
analysis revealed a general fatty acid pattern for the triglycerides, in which the concentration of the saturated acids was
highest in position 1, linoleic acid in 2 and oleic acid in 3. From 20 to 60 days after pollination there was little change
in the fatty acid composition at the 1 position, but the largest changes occurred at the 3 position where palmitic and oleic
acids decreased 5.1% and 7.3%, respectively, and linoleic acid increased 13.4%. The variations in the molecular species of
the triglycerides were determined by silver nitrate thin layer chromatography and were found to be small from 20 to 60 days
after pollination, except for an increase in trilinolein from 5.2 to 11.9%. Stereospecific analyses of four major triglycerides
species, SMD, M2D, SD2, and MD2, revealed larger changes in fatty acid distribution at individual positions during maturation than were apparent from analyses
of the total triglycerides.
Presented in part at the AOCS Meeting, Ottawa, September 1972. 相似文献
56.
33 years after vesiculography using the X-ray contrast remedy Thorotrast on transurethral way in a patient with chronic prostatitis a carcinoma developed in the region of the vesical neck. Histologically the tumour imposed now as a differentiated urothelium carcinoma of medium degree. By autoradiography in the region of the tumour structures radioactive Thorotrast could be proved. On account of the close topographical relations and the long time of latency the development of the carcinoma seems to be ascertained by the then application of Thorotrast. The connections are discussed. 相似文献
57.
After hearing two graduate students in experimental psychology extol learnedly a major theoretical position, the authors were disturbed by a phenomenon that has doubtlessly troubled other psychologists. They wonder why more or less equally intelligent and motivated students, though at different universities, adopt at least superficially but in most cases intrinsically different theoretical biases, each promoting and defending his own belief as though it were verily the most defensible and reasonable theoretical position? Are the various learning theories that different to justify enthusiastic and pious acceptance by comparably capable students? Do celebrated theorists promote their own views comprehensively and dramatically while presenting other views cursorily and sluggishly? Are graduate students really guileless and uncritical? They decry the failure in teaching objectivity in evaluating the numerous theories extant as a serious injustice to the student, who will probably be woefully lacking during later professional maturity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Evelyn Dyb 《Housing Studies》2009,24(6):809-824
This paper presents and discusses the results of a survey of inmates in a representative sample of prisons in Norway. The main conclusion of the study is that imprisonment creates homelessness. While this study and those of others find that approximately one-third of inmates are homeless or live in a precarious housing situation prior to imprisonment, the survey also found that two-thirds were homeless on release. Although the literature on and studies of homelessness and imprisonment are sparse, studies from other countries support this close link between imprisonment and homelessness. There are several reasons why imprisonment should be one of the primary routes into homelessness and the cause of people remaining in precarious housing. The paper also discusses connections between imprisonment, homelessness and social exclusion. 相似文献
59.
Chuang Zhu Evelyn Chalmers Liming Chen Yuqi Wang Ben Bin Xu Yi Li Xuqing Liu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(35)
Flexibility plays a vital role in wearable electronics. Repeated bending often leads to the dramatic decrease of conductivity because of the numerous microcracks formed in the metal coating layer, which is undesirable for flexible conductors. Herein, conductive textile‐based tactile sensors and metal‐coated polyurethane sponge‐based bending sensors with superior flexibility for monitoring human touch and arm motions are proposed, respectively. Tannic acid, a traditional mordant, is introduced to attach to various flexible substrates, providing a perfect platform for catalyst absorbing and subsequent electroless deposition (ELD). By understanding the nucleation, growth, and structure of electroless metal deposits, the surface morphology of metal nanoparticles can be controlled in nanoscale with simple variation of the plating time. When the electroless plating time is 20 min, the normalized resistance (R/R0) of as‐made conductive fibers is only 1.6, which is much lower than a 60 min ELD sample at the same conditions (R/R0 ≈ 5). This is because a large number of unfilled gaps between nanoparticles prevent metal films from cracking under bending. Importantly, the Kelvin problem is relevant to deposited conductive coatings because metallic cells have a honeycomb‐like structure, which is a rationale to explain the relationships of conductivity and flexibility. 相似文献
60.