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101.
The design, synthesis, and biological evaluation of compounds related to the dopamine (DA) uptake inhibitors: 1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)piperazine (1) and 1-[2-[bis-(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine (2) (GBR 12395 and GBR 12909, respectively), directed toward the development and identification of new ligands interacting with high potency and selectivity at the dopamine transporter (DAT) is reported. The substitution of the piperazine ring in the GBR structure with other diamine moieties resulted in the retention of the high affinity of new ligands for the DAT. Some of the modified GBR analogs (e.g. 8, 10, (-)-49, or (-)-50) displayed substantially higher selectivity (4736- to 693-fold) for the dopamine (DA) versus the serotonin (5HT) reuptake site than the parent compounds. The bis(p-fluoro) substitution in the (diphenylmethoxy)ethyl fragment slightly increased the affinity of the ligands at the DA reuptake site but reduced their selectivity at this site (e.g. 9 and 8, 11 and 10, or 17 and 16, respectively). Congeners, such as the series of monosubstituted and symmetrically disubstituted piperazines and trans-2,5-dimethylpiperazines, which lack the (diphenylmethoxy)ethyl substituent lost the affinity for the DAT yet exhibited very high potency for binding to the sigma receptors (e.g.28). The chiral pyrrolidine derivatives of 1, (-)-49, and (+)-49, exhibited an enantioselectivity ratio of 181 and 146 for the inhibition of DA reuptake and binding to the DAT, respectively.  相似文献   
102.
The legume podborer, Maruca vitrata (syn. M. testulalis) (F.) (Lepidoptera: Pyralidae) is a pantropical pest of legume crops. Sex pheromone was collected by gland extraction or trapping of volatiles from virgin female moths originating in India, West Africa, or Taiwan. Analysis by GC-EAG and GC-MS confirmed previously published findings that (E,E)-10,12- hexadecadienal is the most abundant EAG-active component with 2–5% of (E,E)-10,12-hexadecadienol also present. At least one other EAG response was detected at retention times typical of monounsaturated hexadecenals or tetradecenyl acetates, but neither could be detected by GC-MS. Laboratory wind-tunnel bioassays and a field bioassay of blends of (E,E)-10,12-hexadecadienal with (E,E)-10,12-hexadecadienol and a range of monounsaturated hexadecenal and tetradecenyl acetate isomers indicated greatest attraction of males was to those including (E,E)-10,12-hexadecadienol and (E)-10-hexadecenal as minor components. In subsequent trapping experiments in cowpea fields in Benin, traps baited with a three-component blend of (E,E)-10,12-hexadecadienal and these two minor components in a 100:5:5 ratio caught significantly more males than traps baited with the major component alone, either two-component blend, or virgin female moths. Further blend optimization experiments did not produce a more attractive blend. No significant differences in catches were found between traps baited with polyethylene vials or rubber septa, or between lures containing 0.01 and 0.1 mg of synthetic pheromone. Significant numbers of female M. vitrata moths, up to 50% of total catches, were trapped with synthetic blends but not with virgin females. At present there is no clear explanation for this almost unprecedented finding, but the phenomenon may improve the predictive power of traps for population monitoring.  相似文献   
103.
There is a growing emphasis in many countries on matters such as participation in e-government, e-democracy, the provision of forums for online debate, and so on. A critical issue in all of these cases is one of encouraging engagement across a broad spectrum of potentially interested parties and stakeholders. In this paper, we use an ethnographic study of an online event, designed to encourage debate, to explore some critical issues in how the mechanisms productive of debate have shifted in company with the Web 2.0 phenomenon. By contrasting this with a prior study of how players managed their gameplay in a multiplayer pervasive game, we focus upon how different ways of constructing games and events can have serious implications for their ordinary everyday reportability in routine face-to-face interactions. We conclude that designing for reportability should be an active consideration when designing the resources for online debate and consider some ways in which that might be accomplished.  相似文献   
104.
Reviews     
MARK FRESKO CONSULTANCY. Sources of digital information. British Library R&D Report 6102. London: British Library Research and Development Department, 1994. No ISBN given. No price indicated. 260 pp.

CHRIS CLARE and GORDON STUTELEY. Information systemsstrategy to design. London: Chapman and Hall, 1995. ISBN 0 412 576708. £16.99.

POPE, IVAN. Internet UK. Hemel Hempstead: Prentice Hall International, 294 pp. ISBN 013 190950, £19.95. SCHOFIELD, SUE. UK Internet book. Wokingham: Addison‐Wesley, 301 pp. ISBN 0201 42766 4, £19.95.

RIMMER, STEVE. Planet Internet. New York: Windcrest, 1995. ISBN 0 8306 24724. £22.95 (pbk).

JILL H. ELLSWORTH and MATTHEW V. ELLSWORTH. The Internet business book. London: John Wiley & Sons, 1994. $22.95, 376pp. ISBN 0 471058092.

JOHN S. QUARTERMAN and SMOOT CARL‐MITCHELL. The e‐mail companion: communicate effectively via the Internet and other global networks. Addison‐Wesley, 1994. 318 pp. ISBN 0 201 40658 6. $19.95.

McCLURE, C.R., MOEN, W.E. and RYAN, J. Libraries and the Internet/NREN: perspectives, issues and challenges. London: Mecklermedia 1994. $35.00. ISBN 0 89736 824 7. McCLURE, C.R., BERTOT, J.C., and ZWEIZIG, D.L. Public libraries and the Internet: study results, policy issues and recommendations. Washington: National Commission on Libraries and Information Science, 1994. No price or ISBN given.

FRANCES BLOMELEY. Networks and network services: a user's guide. Immediate Publishing, 1994. ISBN 1–89831–00–03. 246 pp. £14.95.

NEIL SMITH (ed) ibraries, networks and Europe: a European networking study. British Library Research and Development Department, 1994. (LIR Series 101) 91 pp. ISBN 0 7123 3295 2. £25. (Distributed by Turpin Distribution Services Ltd, Blackhorse Road, Letchworth, Herts. SG6 1HN).

ALAN BRYANT. Creating successful bulletin board systems. Addison‐Wesley, 1994. ISBN 0–201–62668–3. $39.95.

Directory of electronic journals, newsletters and academic discussion lists. 4th ed. Compiled by Lisabeth A. King and Diane Kovacs, edited by Ann Okerson. Washington, DC: Association of Research Libraries, 1994. 575 pp. ISSN 1057–1337. $54 (paperback), $33 (ARL members).

THE BRITISH LIBRARY and ELECTRONIC PUBLISHING SERVICES LTD. Electronic publishing practice in the UK: LIR Report 95. University Press, Cambridge, 1994. 185 pp. ISBN 0 7123 3280 4. £30.00. (Distributed by Turpin Distribution Services, Blackhorse Road, Letchworth S96 1HN).

INTERNET WORLD'S On Internet 94: an international guide to electronic journals, newsletters, texts, discussion lists, and other resources on the Internet. edited by Tony Abbott with a Preface by Daniel P. Dem. Westport, London: Mecklermedia, 1994. £29.50 $45.00. ISBN 0–88736–929–4.

S. BANG. The Internet unleashed. Indianapolis: SAMS Publishing, 1994. $44.95. ISBN 0 672 30466 X.

GAIL K. DICKINSON, Selection and evaluation of electronic resources. Libraries Unlimited, 1994. ISBN 1 56308 098 2. £22.50.  相似文献   
105.
Resolution of inflammation involves removal of recruited neutrophils from inflamed sites via a noninflammatory mechanism, possibly involving neutrophil apoptosis and engulfment/phagocytosis by macrophages. In this study, we describe the reduction in surface expression (> 90%) of the neutrophil molecule Fc gamma RIII (CD16) during in vitro culture at 37 degrees C, which was found to be temporally associated with the appearance of neutrophils with apoptotic morphology during in vitro culture and inhibitable by granulocyte-macrophage colony-stimulating factor (GM-CSF), which postpones apoptosis in the neutrophil. By using dual fluorescence analysis, CD16 "low" expressing neutrophils showed reduced staining with the DNA-binding dye propidium iodide, suggesting that CD16 low expressing neutrophils were apoptotic. Separation of CD16 "high" and CD16 "low" expressing neutrophils by fluorescence-activated cell sorting revealed that morphologically apoptotic cells exhibited the CD16 low phenotype. We did not observe similar marked changes in expression of other neutrophil surface molecules (including other phosphatidylinositol (PI)-linked molecules), indicating that generalized loss of surface molecules does not occur during apoptosis. We believe this to be the first reported cell type-specific membrane alteration in a surface glycoprotein associated with apoptosis, suggesting that the program of cell death in the neutrophil, in addition to morphologic and nuclear changes, includes alterations in expression of surface receptors.  相似文献   
106.
107.
The high-resolution X-ray structures of the deoxy forms of four recombinant hemoglobins in which Trp37(C3)beta is replaced with Tyr (betaW37Y), Ala (betaW37A), Glu (betaW37E), or Gly (betaW37G) have been refined and analyzed with superposition methods that partition mutation-induced perturbations into quaternary structure changes and tertiary structure changes. In addition, a new cross-validation statistic that is sensitive to local changes in structure (a "local Rfree" parameter) was used as an objective measure of the significance of the tertiary structure changes. No significant mutation-induced changes in tertiary structure are detected at the mutation site itself for any of the four mutants studied. Instead, disruption of the intersubunit contacts associated with Trp37(C3)beta results in (1) a change in quaternary structure at the alpha1beta2 interface, (2) alpha subunit tertiary structure changes that are centered at Asp94(G1)alpha-Pro95(G2)alpha, (3) beta subunit tertiary structure changes that are located between residues Asp99(G1)beta and Asn102(G4)beta, (4) increased mobility of the alpha subunit COOH-terminal dipeptide, and (5) shortening of the Fe-Nepsilon2His(F8) bond in the alpha and beta subunits of the betaW37G and betaW37E mutants. In each case, the magnitude of the change in a particular structural parameter increases in the order betaW37Y < betaW37A < betaW37E approximately betaW37G, which corresponds closely to the degree of functional disruption documented in the preceding papers.  相似文献   
108.
Rhabdoid tumor is a well-accepted clincopathologic entity among childhood renal neoplasms; similar tumors have been described in extrarenal locations. We present the clinicopathologic profile and the immunohistochemical features of a series of soft tissue rhabdoid tumors. Twenty-eight cases coded as extrarenal rhabdoid tumor (ERRT), RT, possible ERRT, and "large cell sarcoma" were retrieved from the Armed Forces Institute of Pathology soft tissue registry. The tumors were reclassified according to strict criteria by light microscopy, clinical information, immunohistochemistry, and, in some cases, electron microscopy. Soft tissue rhabdoid tumor (STRT) was defined as (1) a tumor composed of noncohesive single cells, clusters, or sheets of large tumor cells with abundant glassy eosinophilic cytoplasm, an eccentric vesicular nucleus, and an extremely large nucleolus; (2) positivity for vimentin and/or cytokeratin or other epithelial markers by immunostaining; and (3) exclusion of other tumor types with rhabdoid inclusions (melanoma, other sarcomas, carcinoma). Eighteen cases met our criteria for soft tissue rhabdoid tumors. The median patient age was 13 years (range, 6 months to 56 years). Ninety-four percent of STRT cases were positive for vimentin and 59% for pan-cytokeratin. Sixty-three percent and 60% were positive for CAM 5.2 and EMA, respectively. Seventy-nine percent stained for at least one epithelial marker; 76% stained for both vimentin and epithelial markers simultaneously. Forty-two percent stained for MSA, and 14% for CEA and SMA. CD99, synaptophysin, CD57 (Leu-7), NSE, and focal S100 protein were identified in 75%, 66%, 56%, 54%, and 31% of the STRT cases, respectively. All STRT cases examined were negative for HMB-45, chromogranin, BER-EP4, desmin, myoglobin, CD34, and GFAP. Follow-up examination in 61% of the STRT patients revealed that 64% of patients died of disease within a median follow-up interval of 19 months (range, 4 months to 5 years); 82% had metastases to lung, lymph nodes, or liver; 22% had local recurrences before metastasis; and 18% were alive without known disease status (median, 5.5 years). Soft tissue rhabdoid tumor is a highly aggressive sarcoma, predominantly of childhood. Besides having nearly consistent coexpression of vimentin and epithelial markers, STRTs show positivity for multiple neural/neuroectodermal markers that overlap with those of primitive neuroectodermal tumor.  相似文献   
109.
We have directly determined the amide band resonance Raman spectra of the "average" pure alpha-helix, beta-sheet, and unordered secondary structures by exciting within the amide pi-->pi* transitions at 206.5 nm. The Raman spectra are dominated by the amide bands of the peptide backbone. We have empirically determined the average pure alpha-helix, beta-sheet, and unordered resonance Raman spectra from the amide resonance Raman spectra of 13 proteins with well-known X-ray crystal structures. We demonstrate that we can simultaneously utilize the amide I, II, and III bands and the Calpha-H amide bending vibrations of these average secondary structure spectra to directly determine protein secondary structure. The UV Raman method appears to be complementary, and in some cases superior, to the existing methods, such as CD, VCD, and absorption spectroscopy. In addition, the spectra are immune to the light-scattering artifacts that plague CD, VCD, and IR absorption measurements. Thus, it will be possible to examine proteins in micelles and other scattering media.  相似文献   
110.
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