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991.
992.
IM Goodyer L Ashby PM Altham C Vize PJ Cooper 《Canadian Metallurgical Quarterly》1993,34(8):1409-1423
Temperament (EAS teacher and parent questionnaire) and mental state (modified DISC-C interview with adolescent) was systematically assessed in 193 11 to 16 year olds (112 girls, 81 boys) screened for major depression in the community. Sex differences in the structure of temperament were noted from both parent and teacher reports. High (negative) emotionality alone was associated with major depression, particularly (but not exclusively) in girls. 相似文献
993.
RA Fleming GA Milano MH Gaspard PJ Bargnoux A Thyss R Plagne N Renée M Schneider F Demard 《Canadian Metallurgical Quarterly》1993,(5):740-744
Dihydropyrimidine dehydrogenase (DPD) is the major catabolic enzyme of pyrimidines and fluoropyrimidines. The clinical course of 2 patients with suspected DPD deficiency is described. Both patients had significantly delayed clearance of fluorouracil (5-FU), elevated plasma uracil concentrations, and subsequent lethal toxicity. The prevalence of DPD deficiency in the general population is unknown, but given the large number of cancer patients treated with 5-FU, it may be of great clinical significance. Lymphocytes have been previously shown to be a useful marker of systemic DPD activity. Because DPD activity has not been previously reported in a large population of cancer patients using 5-FU as the substrate, we determined DPD activity in lymphocytes from 66 patients with cancer. DPD activity was determined by a sensitive high performance liquid chromatography method. The mean DPD activity (S.D.) in 66 patients with head and neck cancer was 0.189 (0.071) nomol/min/mg protein with wide interpatient variability (range 0.058-0.357). DPD activity was not correlated to age (r = -0.164, P = 0.188). The mean DPD activity in men [0.192 (0.074)] was not significantly different from that in women [0.172 (0.057); t-test P = 0.418]. Likewise, there was no statistical difference in DPD activity in patients who had not received prior chemotherapy [0.195 (0.066)] to patients receiving one or more cycles of chemotherapy [0.186 (0.074); t-test P = 0.638]. 相似文献
994.
The article reviews the growing body of literature that examines academic nursing centers in the aggregate including the first such study conducted by the primary author 5 years earlier. A follow-up study to this original work was conducted to determine current demographics and faculty practice policies of schools or colleges of nursing that operate nursing centers and to compare these findings with those of schools without nursing centers. A survey was sent to the deans or directors of the 462 National League of Nursing (NLN)-accredited baccalaureate nursing programs. Although there were 362 respondents to the survey (78 per cent), only 41 indicated they had a nursing center. Schools with nursing centers were significantly more likely to be in public institutions (P = .05), and offer master's degrees (P = .01). They also were significantly larger (P = .01), with a mean of 34 full time-equivalent (FTE) faculty members. Then the administrative policies of schools with nursing centers (N = 41) were compared with those of schools without centers but with practicing faculty (N = 187). Requiring practice was not a common policy in either group. While about one-third of both groups had practice plans, the majority were described as informal. More schools with nursing centers had other formalized practice arrangements than did schools without centers (P = .01). Faculty practice was more likely to be a criterion for promotion (P = .05) but not for tenure in schools with nursing centers. An inverse relationship (P = .05) was found between the amount of practice revenue generated and the presence of a nursing center.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
995.
Labourdette J.-F.P. Hart G.W. Acampora A.S. 《Communications, IEEE Transactions on》1994,42(10):2822-2832
Some of today's telecommunications networks have the ability to superimpose some form of logical connectivity, or virtual topology, on top of the underlying physical infrastructure. According to the degree of independence between the logical connectivity and the physical topology, the network can dynamically adapt its virtual topology to track changing traffic conditions, and cope with failure of network equipment. This is particularly true for lightwave networks, where a logical connection diagram is achieved by assignment of transmitting and receiving wavelengths to the network stations that tap into, and communicate over, an infrastructure of fiber glass. Use of tunable transmitters and/or receivers allow the logical connectivity to be optimized to prevailing traffic conditions. With rearrangeability having thus emerged as a powerful network attribute, this paper discusses the reconfiguration phase which is the transition between the current logical connection diagram and a target diagram. We consider here an approach where the network reaches some target connectivity graph through a sequence of intermediate connection diagrams, so that two successive diagrams differ by a single branch-exchange operation. This is an attempt at logically reconfiguring the network in a way that is minimally disruptive to the traffic. We propose and compare three polynomial-time algorithms that search for “short” sequences of branch-exchange operations, so as to minimize the overall reconfiguration time. For networks made of up to 40 stations, theoretical and simulation results show that, when a randomly selected diagram is to be changed to another randomly chosen diagram, the average number of branch-exchange operations required grows linearly with the size of the network 相似文献
996.
997.
PJ Whalen G Bush RJ McNally S Wilhelm SC McInerney MA Jenike SL Rauch 《Canadian Metallurgical Quarterly》1998,44(12):1219-1228
BACKGROUND: The emotional counting Stroop (ecStroop) functional magnetic resonance imaging (fMRI) activation paradigm was designed to recruit the anterior cingulate affective division (ACad). METHODS: Nine normal, healthy male and female subjects (mean age 24.2 years) reported via button press the number of neutral and negative words that appeared on a screen while reaction time and fMRI data were acquired. RESULTS: We observed a) greater ACad activation for negative versus neutral words during initial presentation blocks; b) lower overall ACad signal intensity during task performance (i.e., both negative and neutral words) compared to the baseline fixation condition; and c) no reaction time increase to negative versus neutral words. CONCLUSIONS: In a companion study of a cognitive version of the counting Stroop (Bush et al 1998), these same 9 subjects a) activated the more dorsal anterior cingulate cognitive division; b) also showed the overall decrease in ACad signal intensity; and c) demonstrated a reliable reaction time effect. Taken together, these data offer a within-group spatial dissociation of AC function based upon information content (i.e., cognitive vs. emotional) and/or presence of behavioral interference. We propose that the ecStroop will be a useful fMRI probe of ACad function in anxiety disorders. 相似文献
998.
In allogeneic marrow transplantation, donor T cells that recognize recipient alloantigens prevent rejection but also cause graft-versus-host disease (GVHD). To evaluate whether the ability to prevent marrow graft rejection could be dissociated from the ability to cause GVHD, we generated a panel of four different CD8 cytotoxic T-lymphocyte clones specific for H2(d) alloantigens. Three of the clones caused no overt toxicity when as many as 20 x 10(6) cells were infused intravenously into irradiated H2(d)-positive recipients, and one clone caused acute lethal toxicity within 1 to 3 days after transferring 10 x 10(6) cells into H2(d)-positive recipients. One clone that did not cause toxicity was able to prevent rejection of (C57BL/6J x C3H/HeJ)F1 marrow in 800 cGy-irradiated (BALB/cJ x C57BL/6J)F1 recipients without causing GVHD. Large numbers of cells and exogenously administered interleukin-2 were required to prevent rejection. These results with different CD8 clones suggest that GVHD and prevention of rejection could be separable effects mediated by distinct populations of donor T cells that recognize recipient alloantigens. 相似文献
999.
OBJECTIVE: Amylin, a secretory peptide of beta-cells, is the constituent peptide of islet amyloid, which is characteristic of NIDDM, and changes in amylin secretion in response to therapies may influence the rate of production of islet amyloid. The primary objective of this study was to determine whether therapy with sulfonylurea or basal insulin in NIDDM would alter amylin secretion in a way that might affect the formation of islet amyloid. RESEARCH DESIGN AND METHODS: In a randomized crossover design, eight subjects with NIDDM underwent three 8-week periods of therapy with diet alone, sulfonylurea, or exogenous basal insulin, with evaluation of amylin, amylin-like peptide (ALP), and glucose and C-peptide concentrations, both during fasting and after a standard breakfast. Changes in beta-cell function (% beta) were assessed, in the basal state by homeostasis model assessment (HOMA) and in the stimulated state by hyperglycemic clamps. Seven nondiabetic control subjects each underwent a meal profile and hyperglycemic clamp. RESULTS: Both sulfonylurea and insulin therapy reduced basal glucose concentrations compared with diet alone, but neither reduced the increased postprandial glucose increments. Both sulfonylurea and insulin therapy increased basal % beta, assessed by HOMA, but only sulfonylurea increased the second-phase C-peptide responses to the hyperglycemic clamp. Sulfonylurea increased time-averaged mean postprandial amylin and ALP concentrations compared with diet alone (geometric mean [1-SD range] for amylin, 4.9 [2.0-11.8] vs. 3.0 [1.4-6.2] pmol/l, P = 0.003; for ALP, 16.4 [8.5-31.7] vs. 10.1 [4.9-20.8] pmol/l, P = 0.001). Insulin therapy reduced basal ALP concentrations compared with diet alone (2.9 [1.5-5.6] vs. 6.0 [2.6-13.6] pmol/l, P = 0.03), but had no effect on postprandial concentrations of amylin (3.0 [1.3-6.5] pmol/l) or ALP (10.0 [5.5-18.1] pmol/l). CONCLUSIONS: By increasing postprandial concentrations of the constituent peptides of islet amyloid, sulfonylurea therapy might increase the rate of deposition of islet amyloid and thereby accelerate the decline of % beta in NIDDM, compared with diet therapy alone. 相似文献
1000.
A feline herpesvirus-1 recombinant with a deletion in the genes for glycoproteins gI and gE is effective as a vaccine for feline rhinotracheitis 总被引:1,自引:0,他引:1
Using a site-directed mutagenesis technique we constructed a new feline herpesvirus-1 recombinant strain containing a deletion in two genes encoding glycoproteins gI and gE. These proteins may have a role in virulence, the establishment of latency, and viral recurrence as shown in other herpesviruses of the varicella and simplex types. This recombinant was characterized and used to immunize juvenile cats against virulent virus challenge. Significant protection resulted from vaccination of cats by the subcutaneous route. 相似文献