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151.
Anxiety levels in a sample of 65 long-term cancer survivors were assessed in a study of the effects of a planned discharge from an oncology clinic. Thirty-one percent of patients scored > or = 8, and 12% > or = 11 on the anxiety subscale of the Hospital Anxiety and Depression Scale (HADS), indicating that anxiety rates in patients in long-standing remission do not greatly differ from patients with active disease. Despite the provision of continued support and guaranteed fast-access return to the clinic if necessary, 28% of patients refused to be discharged. Fear that recurrence would not be detected was the reason most frequently cited. Seventy-five percent of these patients were HADS anxiety cases. A second assessment 4-5 months later of the 41 patients who were discharged showed a slight, but non-significant increase in anxiety rates suggesting that anxiety in cancer survivors may be persistent and not related to clinic attendance. 相似文献
152.
Measuring vocabulary diversity using dedicated software 总被引:3,自引:0,他引:3
153.
Sundstrom Eric; McIntyre Michael; Halfhill Terry; Richards Heather 《Canadian Metallurgical Quarterly》2000,4(1):44
This article summarizes the Hawthorne studies related to work groups and their legacy and traces applications of work groups and related empirical research through the 1990s. A selective review of empirical studies of work group effectiveness conducted in work settings and published in the last 20 years addresses 4 questions: (a) What identifying features have field researchers used in operationally defining work groups? (b) What research strategies have been used, and to address what kinds of questions? (c) What criteria of work group effectiveness has the field research measured, using what sources of data? (d) What variables have researchers sought to link with measures of work group effectiveness? On the basis of answers to these questions, an agenda for future research about work groups and work teams is suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
154.
The synthesis of well-defined, monodisperse AB2 and AB3 miktoarm star copolymers, in which A is polydeuterobutadiene and B is polybutadiene, is described. The synthetic procedure
involved reacting living polydeuterobutadiene with a large excess of either methyltrichlorosilane or tetrachlorosilane to
yield a ‘one-arm star’. SEC traces of this ‘one-arm star’ are indistinguishable from that of the uncoupled polydeuterobutadiene
indicating no further coupling to form multi-arm stars occurs. Unreacted chlorosilane was removed by distillation and the
introduction of an excess of living polybutadiene generates the star. The star polymer was isolated from the precursor polybutadiene
by fractionation.
Received: 27 April 1998/Revised version: 15 June 1998/Accepted: 16 June 1998 相似文献
155.
Feil IK; Platas AA; van den Akker F; Reddy R; Merritt EA; Storm DR; Hol WG 《Protein engineering, design & selection : PEDS》1998,11(11):1103-1109
Members of the cholera toxin family, including Escherichia coli heat-
labile enterotoxins LT-I and LT-II, catalyze the covalent modification of
intracellular proteins by transfer of ADP-ribose from NAD to a specific
arginine of the target protein. The ADP-ribosylating activity of these
toxins is located in the A-subunit, for which LT-I and LT-II share a 63%
sequence identity. The flexible loop in LT-I, ranging from residue 47 to
56, closes over the active site cleft. Previous studies have shown that
point mutations in this loop have dramatic effects on the activity of LT-I.
Yet, in LT-II the sequence of the equivalent loop differs at four positions
from LT-I. Therefore five mutants of the active site loop were created by a
stepwise replacement of the loop sequence in LT-I with virtually all the
corresponding residues in LT- II. Since we discovered that LT-II had no
activity versus the artificial substrate
diethylamino-benzylidine-aminoguanidine (DEABAG) while LT-I does, our
active site mutants most likely probe the NAD binding, not the arginine
binding region of the active site. The five hybrid toxins obtained (Q49A,
F52N, V53T, Q49V/F52N and Q49V/F52N/V53T) show (i) great differences in
holotoxin assembly efficiency; (ii) decreased cytotoxicity in Chinese
hamster ovary cells; and (iii) increased in vitro enzymatic activity
compared with wild type LT-I. Specifically, the three mutants containing
the F52N substitution display a greater Vmax for NAD than wild type LT-I.
The enzymatic activity of the V53T mutant is significantly higher than that
of wild type LT-I. Apparently this subtle variation at position 53 is
beneficial, in contrast to several other substitutions at position 53 which
previously had been shown to be deleterious for activity. The most striking
result of this study is that the active site loop of LT- I, despite great
sensitivity for point mutations, can essentially be replaced by the active
site loop of LT-II, yielding an active 'hybrid enzyme' as well as 'hybrid
toxin'.
相似文献
156.
This study scrutinized people's ability to apply different strategies to randomly intermixed immediate and delayed test items. In three experiments a total of 221 participants first read one set of stories. Later, they read more stories, and after each one, answered intermixed questions about that story and one of the earlier ones. The experiments cumulatively manipulated amount of delay, test probe plausibility, probe relation (explicit, paraphrase, inference), and testing procedure (mixed versus uniform delay). Using signal detection response criterion as the index of strategy, the authors contrasted the single criterion hypothesis, according to which one text retrieval criterion is applied to all test items and a multiple-criterion hypothesis. The results consistently favoured the multiple-criterion hypothesis. The results also indicated that the presence of immediate and delayed probes mutually influence one another less extreme signal detection criteria were adopted under mixed than uniform testing. It was concluded that text retrieval strategy is continually calibrated with reference to the quality of the test probes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
A coherent optical receiver using a multiport optical coupler to provide phase diversity is described. By this means, only homodyne bandwidth is required in the signal processing, but with tolerances on the frequency tracking typical of heterodyne systems. Measured sensitivities with limited local-oscillator power are ?47.5 dBm at 320 Mbit/s and ?42 dBm at 680 Mbit/s. The results at the higher bit rate are strongly influenced by limited receiver module bandwidth. 相似文献
158.
Dual-band reactively loaded microstrip antenna 总被引:2,自引:0,他引:2
A previously derived theory is applied to a microstrip antenna with a reactive load to produce a dual-band radiator. A model consisting of a rectangular patch radiator loaded with a variable length short-circuited coaxial stub was investigated experimentally. Comparisons of theoretical predictions and experimental data are made for the impedance and resonant frequencies as a function of the position of the load, the length of the stub, and the characteristic impedance of the stub. 相似文献
159.
160.