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31.
Prior electrical stimulation of the medial prefrontal cortex MFC facilitated the subsequent acquisition of intracranial self-stimulation (ICSS) from the same MFC electrode site. Stimulations that were spaced over a period of six days were more effective in producing this facilitation than the same number of stimulations delivered over a two day period. These data suggest that the rewarding effects of MFC stimulation may involve some process akin to the kindling phenomenon and as such may provide insights in the neuronal modifications thought to underlie learning and memory. 相似文献
32.
33.
McKenzie BS Corbett AJ Brady JL Dyer CM Strugnell RA Kent SJ Kramer DR Boyle JS Lew AM 《Immunologic research》2001,24(3):225-244
There are no adequate vaccines against some of the new or reemerged infectious scourges such as HIV and TB. They may require
strong and enduring cell-mediated immunity to be elicited. This is quite a task, as the only known basis of protection by
current commercial vaccines is antibody. As DNA or RNA vaccines may induce both cell-mediated and humoral immunity, great
interest has been shown in them. However, doubt remains whether their efficacy will suffice for their clinical realization.
We look at the various tactics to increase the potency of nucleic acid vaccines and divided them broadly under those affecting
delivery and those affecting immune induction. For delivery, we have considered ways of improving uptake and the use of bacterial,
replicon or viral vectors. For immune induction, we considered aspects of immunostimulatory CpG motifs, coinjection of cytokines
or costimulators and alterations of the antigen, its cellular localization and its anatomical localization including the use
of ligand-targeting to lymphoid tissue. We also thought that mucosal application of DNA deserved a separate section. In this
review, we have taken the liberty to discuss these enhancement methods, whenever possible, in the context of the underlying
mechanisms that might argue for or against these strategies. 相似文献
34.
Summary A case of a 44-year-old woman with a solitary pulmonary coin lesion is presented. Histologic study of this nodule revealed a normal intraparenchymal pulmonary lymph node. A review of the literature discusses the incidence and characteristics of this entity.
Nud lymphatique intrapulmonaire: revue de la littérature. A propos d'un cas
Résumé L'observation d'un cas de lésion nodulaire du poumon est rapportée chez une femme de 44 ans. L'étude histologique du nodule a révélé un nud lymphatique intrapulmonaire normal. La revue de la littérature apprécie l'incidence et les caractéristiques de cette localisation.相似文献
35.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
36.
Rebecca Nzawa Soko Rachael M. Burke Helena R.A. Feasey Wakumanya Sibande Marriott Nliwasa Marc Y.R. Henrion McEwen Khundi Peter J. Dodd Chu Chang Ku Gift Kawalazira Augustine T. Choko Titus H. Divala Elizabeth L. Corbett Peter MacPherson 《Emerging infectious diseases》2021,27(7):1831
The coronavirus disease (COVID-19) pandemic might affect tuberculosis (TB) diagnosis and patient care. We analyzed a citywide electronic TB register in Blantyre, Malawi and interviewed TB officers. Malawi did not have an official COVID-19 lockdown but closed schools and borders on March 23, 2020. In an interrupted time series analysis, we noted an immediate 35.9% reduction in TB notifications in April 2020; notifications recovered to near prepandemic numbers by December 2020. However, 333 fewer cumulative TB notifications were received than anticipated. Women and girls were affected more (30.7% fewer cases) than men and boys (20.9% fewer cases). Fear of COVID-19 infection, temporary facility closures, inadequate personal protective equipment, and COVID-19 stigma because of similar symptoms to TB were mentioned as reasons for fewer people being diagnosed with TB. Public health measures could benefit control of both TB and COVID-19, but only if TB diagnostic services remain accessible and are considered safe to attend. 相似文献
37.
Smoking cessation factors among African Americans and whites. COMMIT Research Group. 总被引:7,自引:4,他引:3
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J M Royce N Hymowitz K Corbett T D Hartwell M A Orlandi 《American journal of public health》1993,83(2):220-226
OBJECTIVES. This study was undertaken to explore smoking patterns and attitudes that influence smoking cessation and relapse among African Americans. METHODS. Baseline data from eight Community Intervention Trial for Smoking Cessation (COMMIT) sites were analyzed. RESULTS. Compared with Whites, African Americans who smoke less than 25 cigarettes per day were 1.6 times more likely to smoke within 10 minutes of awakening (a behavioral indicator of nicotine dependence), adjusting for education, age, and gender (OR = 1.2 for heavier smokers). African Americans reported a stronger desire to quit smoking and reported serious quit attempts in the past year. African Americans favored tobacco restrictions (they were 1.8 times more likely than Whites to view smoking as a serious community problem, 1.7 times more likely to favor restrictions on cigarette vending machines, and 2.1 times more likely to prohibit smoking in their car). African Americans were lighter/moderate, menthol smokers. CONCLUSIONS. African Americans find smoking socially unacceptable and are strongly motivated to quit, but their "wake-up" smoking may indicate high nicotine dependence, making abstinence difficult even for lighter smokers. 相似文献
38.
Woods-Kettelberger A Kongsamut S Smith CP Winslow JT Corbett R 《Expert opinion on investigational drugs》1997,6(10):1369-1381
The availability of an animal model for obsessive-compulsive disorder (OCD) is necessary for the development of novel pharmacological treatments. To be useful, the model must be predictive of clinical performance, possess characteristic criteria and distinguish anti-OCD from antidepressant compounds. Due to the lack of OCD models useful for drug discovery, all compounds currently used for OCD were developed first as antidepressants. In this article, we discuss the relative merits of: stereotypic behaviours (canine acral lick, feather picking, amphetamine- and 5-HT-induced stereotypy); adjunctive and displacement behaviours (schedule-induced polydipsia, wheel running, resident-intruder grooming); anxiolytic tests (separation and shock-induced ultrasonic vocalisation and marble burying); and depression tests (inescapable shock-induced escape and immobility in forced swim) as potential OCD models. We conclude that adjunctive and displacement behaviours, and in particular schedule-induced polydipsia, may prove to be the best models for compulsive behaviour in animals that can be used for the discovery of novel anti-OCD agents. 相似文献
39.
J S Kutner J F Steiner K K Corbett D W Jahnigen P L Barton 《Social science & medicine (1982)》1999,48(10):1341-1352
Despite evidence that doctor-patient communication affects important patient outcomes, patient expectations are often not met. Communication is especially important in terminal illness, when the appropriate course of action may depend more on patient values than on medical dogma. We sought to describe the issues important to terminally ill patients receiving palliative care and to determine whether patient characteristics influence the needs of these patients. We utilized a multimethod approach, first conducting interviews with 22 terminally ill individuals, then using these data to develop a more structured instrument which was administered to a second population of 56 terminally ill patients. Patient needs and concerns were described and associations between patient characteristics and issues of importance were evaluated. Seven key issues were identified in the initial interviews: change in functional status or activity level; role change; symptoms, especially pain; stress of the illness on family members; loss of control; financial burden and conflict between wanting to know what is going on and fearing bad news. Overall, respondent needs were both disease- and illness-oriented. Few easily identifiable patient characteristics were associated with expressed concerns or needs, suggesting that physicians need to individually assess patient needs. Terminally ill patients receiving palliative care had needs that were broad in scope. Given that few patient characteristics predicted responses, and that the majority opinion may not accurately reflect that of an individual patient, health care providers must be aware of the diverse concerns among this population and individualize assessment of each patient's needs and expectations. 相似文献
40.