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31.
32.
IE Gushanski? 《Canadian Metallurgical Quarterly》1997,97(12):20-23
There were studied 23 schizophrenic and cyclothymic patients with stable agoraphobia in the structure of anxiousphobic disorders (APD). No absolute correlation was found between stability of agoraphobia and severity of panic disorder (frequency and intensity of panic attacks). It was established that APD with manifestations of agoraphobia had been, perhaps, conditioned by the presence of comorbid disturbances in their structure which had determined peculiarities of the patients' behavior. Two types of prolonged APD with agoraphobic phenomena were recognized. Retention of agoraphobic disturbances in conditions of the first type was related to symptoms of generalized somatic disorder (generalized somatic anxiety) in clinical pattern of APD. Manifestations similar to panphobias prevailed, agoraphobic avoidance included all the situations in which the patient could find himself without help. In the states of the second type retention of agoraphobic disorders was conditioned by comorbidity of APD with asthenohypochondriac manifestations with somato-psychic fragility in their structure. Anxiety of expectation was formed in situations with emotional or physical tension. Agoraphobic avoidance in conditions of this type had displayed the character of preventive measures and one of manifestations of hypochondriac development of personality. The presence of pronounced anxiety (intensive panic attacks, generalized anxiety) in clinical pattern of prolonged agoraphobic conditions can serve a predictor of a favourable development of the disease. 相似文献
33.
Jing Tang Kamalabadi F. Rumsey L.G. Swenson G.R. 《Geoscience and Remote Sensing, IEEE Transactions on》2003,41(1):146-152
Spectroscopic images of atmospheric chemiluminescent airglow contain fundamental diagnostic information about the structure and dynamics of the upper atmosphere. However, westward movement of stars causes non-negligible contamination in the two-dimensional horizontal wavenumber spectra extracted from all-sky airglow images. The conventional star-removing scheme is not effective in attenuating the star artifacts in the spectra of emission intensities of gravity wave perturbation, hindering the subsequent calculation of the angular spectra and the momentum fluxes of the profiles. To address this problem, a gradient-based edge detection algorithm for locating and attenuating the undesired star signal is developed. Comparatively, this algorithm is more effective than the conventional star-removing methods. The algorithm is validated in the context of experimentally obtained spectra. 相似文献
34.
Nurses employed by schools and health departments have varying responsibilities for curricula related to menstruation, menarche, and sexuality. Nevertheless, the school nurse is usually a source of information on these subjects whether employed full-time in school health or also participating in other nursing roles in the community. This survey examines the involvement of school nurses in curricula related to human reproduction including contraception. Data about their involvement in these classroom topics provides a basis for evaluating their roles and making recommendations for subsequent continuing education programs for school health nurses. 相似文献
35.
Brain acetylhydrolase that inactivates platelet-activating factor is a G-protein-like trimer 总被引:1,自引:0,他引:1
YS Ho L Swenson U Derewenda L Serre Y Wei Z Dauter M Hattori T Adachi J Aoki H Arai K Inoue ZS Derewenda 《Canadian Metallurgical Quarterly》1997,385(6611):89-93
The platelet-activating factor PAF (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is a potent lipid first messenger active in general cell activation, fertilization, inflammatory and allergic reactions, asthma, HIV pathogenesis, carcinogenesis, and apoptosis. There is substantial evidence that PAF is involved in intracellular signalling, but the pathways are poorly understood. Inactivation of PAF is carried out by specific intra- and extracellular acetylhydrolases (PAF-AHs), a subfamily of phospholipases A2 that remove the sn-2 acetyl group. Mammalian brain contains at least three intracellular isoforms, of which PAF-AH(Ib) is the best characterized. This isoform contains a heterodimer of two homologous catalytic subunits alpha1 and alpha2, each of relative molecular mass 26K, and a non-catalytic 45K beta-subunit, a homologue of the beta-subunit of trimeric G proteins. We now report the crystal structure of the bovine alpha1 subunit of PAF-AH(Ib) at 1.7 A resolution in complex with a reaction product, acetate. The tertiary fold of this protein is closely reminiscent of that found in p21(ras) and other GTPases. The active site is made up of a trypsin-like triad of Ser 47, His 195 and Asp 192. Thus, the intact PAF-AH(Ib) molecule is an unusual G-protein-like (alpha1/alpha2)beta trimer. 相似文献
36.
The aim of this study was to establish whether there is non-geniculostriate input to the extrastriate motion-sensitive area V5 in humans. Responses were measured with a SQUID neuro-magnetometer to motion stimuli presented within the blind hemifield of GY, a well-documented subject with a complete absence of the left primary visual cortical area V1. The motion stimulus was a 0.5c/deg, rapidly drifting (16Hz) achromatic sinusoidal grating. With this stimulus, the magnetic responses recorded over the temporo-parieto-occipital region in normals are well modelled by localized current sources in areas V1 and V5 (Anderson, S. J. et al., Proceedings of the Royal Society, London, Series B, 1996, 263, 423-431). As a control, evoked responses were measured to a 1.0 c/deg, stationary, photometrically isoluminant red/green sinusoidal grating. With the chromatic stimulus, the principal component of the magnetic responses recorded over the occipital pole in normals is well modelled by a current source in area V1 (Fylan, F. et al., Investigative Ophthalmology and Visual Science, 1995, 36, s1053). Both stimuli subtended 4 deg vertically by 6 deg horizontally, positioned such that the stimulus extended beyond the area of macular sparing into the lower field quadrant of the blind (or sighted) hemifield. Chromatic stimuli failed to evoked responses from GY's blind (contralateral) hemifield, consistent with there being no V1 activity in his left cortical hemisphere. However, motion stimuli did evoke responses from GY's blind hemifield, originating from a location consistent with activity in area V5. We further observed that both colour and motion stimuli evoked responses from GY's sighted (ipsilateral) hemifield. We conclude that there is non-geniculostriate input to extrastriate motion-sensitive areas in the human visual system, and that this pathway subserves the residual visual sensitivity to motion in the blind hemifield that has been demonstrated psychophysically in observer GY. 相似文献
37.
T Valerius B Stockmeyer AB van Spriel RF Graziano IE van den Herik-Oudijk R Repp YM Deo J Lund JR Kalden M Gramatzki JG van de Winkel 《Canadian Metallurgical Quarterly》1997,90(11):4485-4492
Promising results from clinical trials with unconjugated antibodies stimulated renewed interest in immune effector mechanisms of monoclonal antibodies (MoAbs). We investigated the potential of IgA as antibody isotype for cell- or complement-mediated tumor cell lysis and assessed the potential of its myeloid Fc receptor, FcalphaRI (CD89), as trigger molecule for bispecific antibody (BsAb)-mediated immunotherapy. Comparing hapten-directed antibodies of human IgA2 with IgG1 or IgG3 isotypes, we found all three to mediate effective killing of sensitized tumor target cells in whole blood assays. Analysis of effector mechanisms showed IgG-mediated lysis to be predominantly complement-dependent, whereas IgA-dependent killing was primarily effector cell-mediated. A comparison of effector cell populations in antibody-dependent cell-mediated cytotoxicity (ADCC) showed neutrophils to be most important for IgA-dependent tumor cell killing, involving FcalphaRI as shown with Fc receptor blocking antibodies. Reverse ADCC experiments against target cells sensitized with Fc receptor antibodies, or assays with FcalphaRI-directed bispecific antibodies confirmed FcalphaRI as effective trigger molecule in polymorphonuclear neutrophil (PMN)-mediated lysis. During granulocyte colony-stimulating factor (G-CSF ) therapy, (FcalphaRI x HER-2/neu) bispecific antibodies induced enhanced killing of HER-2/neu positive SK-BR-3 breast cancer cells in whole blood assays. This enhanced cytotoxicity was paralleled by increased PMN counts, which lead to higher effector to target cell ratios in G-CSF-primed blood. Furthermore, bispecific antibodies, directed to FcalphaRI and Candida albicans, enhanced neutrophils' phagocytosis of fungi. In summary, these results identify IgA as an effective antibody isotype for immunotherapy, working primarily via FcalphaRI on neutrophils. They suggest FcalphaRI-directed bispecific antibodies and G-CSF to be an attractive combination for malignant or infectious diseases. 相似文献
38.
S. Hailey-Dunsheath P. S. Barry C. M. Bradford G. Chattopadhyay P. Day S. Doyle M. Hollister A. Kovacs H. G. LeDuc N. Llombart P. Mauskopf C. McKenney R. Monroe H. T. Nguyen R. O’Brient S. Padin T. Reck E. Shirokoff L. Swenson C. E. Tucker J. Zmuidzinas 《Journal of Low Temperature Physics》2014,176(5-6):841-847
SuperSpec is a novel on-chip spectrometer we are developing for (sub)millimeter wavelength astronomy. Our approach utilizes a filterbank of moderate resolution ( \(R \sim 500{)}\) channels, coupled to lumped element kinetic inductance detectors (KIDs), all integrated onto a single silicon chip. The channels are half-wave resonators formed by lithographically depositing segments of superconducting transmission line, and the KIDs are titanium nitride resonators. Here we present optical measurements of a first generation prototype, operating in the 180–280 GHz frequency range. We have used a coherent source to measure the spectral profiles of 17 channels, which achieve linewidths corresponding to quality factors as high as \(Q_\mathrm {filt} = 700{,}\) consistent with the designed values plus additional dissipation characterized by \(Q_i \approx 1440{.}\) We have also used a Fourier Transform Spectrometer to characterize the spectral purity of all 72 channels on the chip, and measure typical out of band responses \({\sim }30\) dB below the peak response. 相似文献
39.
Design and Performance of SuperSpec: An On-Chip,KID-Based,mm-Wavelength Spectrometer 总被引:1,自引:0,他引:1
E. Shirokoff P. S. Barry C. M. Bradford G. Chattopadhyay P. Day S. Doyle S. Hailey-Dunsheath M. I. Hollister A. Kovács H. G. Leduc C. M. McKenney P. Mauskopf H. T. Nguyen R. O’Brient S. Padin T. J. Reck L. J. Swenson C. E. Tucker J. Zmuidzinas 《Journal of Low Temperature Physics》2014,176(5-6):657-662
SuperSpec is an ultra-compact spectrometer-on-a-chip for mm and submm wavelength astronomy. Its very small size, wide spectral bandwidth, and highly multiplexed detector readout will enable construction of powerful multi-object spectrometers for observations of galaxies at high redshift. SuperSpec is a filter bank with planar, lithographed, superconducting transmission line resonator filters and lumped-element kinetic inductance detectors made from Titanium Nitride. We have built an 81 detector prototype that operates in the 195–310 GHz band. The prototype has a wide-band metal feed horn with a transition to microstrip that feeds the filter bank. The prototype has demonstrated optical filter bank channels with a range of resolving powers from 300 to 700, measured fractional frequency noise of \(10^{-17} \mathrm{Hz}^{-1}\) at \(1\,\) Hz. 相似文献
40.
Relations of overt and relational aggression with perceived popularity among children and early adolescents were examined in 2 studies (Ns = 607 and 1,049). Among older youths, positive concurrent relations found between overt aggression and perceived popularity became nonsignificant when relational aggression was controlled, whereas positive associations found between relational aggression and perceived popularity held when overt aggression was controlled. Aggression and perceived popularity were not positively related for the younger participants. The 2nd study also examined the temporal ordering of these relations over 6 months. For older girls, positive relations between relational aggression and perceived popularity were bidirectional. For older boys, relational aggression did not predict increased perceived popularity, but perceived popularity predicted increased relational aggression. Implications for intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献