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1.
Diabet Med ; 29(10): 1327-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22417295

RESUMO

AIMS: To estimate direct costs of paediatric Type 1 diabetes care and associated factors in Germany for the year 2007 and to compare results with the costs for the year 2000. METHODS: Our study includes clinical data and charges for any diabetes-related health care service of 14,185 continually treated subjects with paediatric diabetes aged < 20 years [52.5% male, mean age (SD) 12.1 (4.2) years], derived from a nationwide prospective patient documentation system (DPV). Health-care utilization was valued in monetary terms by using inpatient and outpatient medical fees and retail prices (perspective of the statutory health insurance). Associations between average total diabetes-related costs or various single cost categories per patient and age, sex, migration background, diabetes duration, and metabolic control were analysed by multiple regression procedures and by a two-part model for hospitalization costs. Total direct costs in the whole paediatric diabetes population in Germany were estimated. Mean costs per patient as well as total costs in the German paediatric diabetes population in 2007 were compared to 2000 costs (inflated to the year 2007). RESULTS: Mean direct diabetes-associated costs per subject were €3524 (inter-quartile range: 1831-4743). Main cost categories were hospitalization (32%), glucose self-monitoring (29%), insulin pump therapy (18%), and insulin (15%). Based on the present estimation, the total costs of paediatric diabetes care in Germany exceeded €110 million in 2007. Compared with estimates of the year 2000, average costs per patient had increased by 20% and total costs for German paediatric diabetes care by 47%. CONCLUSIONS: Direct costs for paediatric Type 1 diabetes care increased between 2000 and 2007, probably partly because of new therapeutic strategies and an increase in diabetes prevalence.


Assuntos
Assistência Ambulatorial/economia , Diabetes Mellitus Tipo 1/economia , Custos de Cuidados de Saúde , Hospitalização/economia , Hipoglicemiantes/economia , Insulina/economia , Adolescente , Automonitorização da Glicemia/economia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Alemanha/epidemiologia , Custos de Cuidados de Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Hipoglicemiantes/administração & dosagem , Lactente , Recém-Nascido , Insulina/administração & dosagem , Masculino , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
2.
Phys Rev Lett ; 107(26): 267601, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-22243181

RESUMO

Angle-resolved photoelectron spectroscopy (ARPES) was used to study the Fermi surface of the heavy-fermion system YbRh(2)Si(2) at a temperature of about 10 K, i.e., a factor of 2 below the Kondo energy scale. We observed sharp structures with a well-defined topology, which were analyzed by comparing with results of band-structure calculations based on the local-density approximation (LDA). The observed bulk Fermi surface presents strong similarities with that expected for a trivalent Yb state, but is slightly larger, has a strong Yb-4f character, and deviates from the LDA results by a larger region without states around the Γ point. These properties are qualitatively explained in the framework of a simple f-d hybridization model. Our analysis highlights the importance of taking into account surface states and doing an appropriate projection along k(z) when comparing ARPES data with results from theoretical calculations.

3.
Clin Genet ; 78(2): 149-61, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20236110

RESUMO

The increasing use of array-comparative genomic hybridization (array-CGH) to identify copy number variations (CNVs) in patients with developmental delay (DD), mental retardation and/or dysmorphic features has allowed the recent recognition of numerous genomic imbalances, including the 15q13.3 microdeletion. Patients with this microdeletion generally present with relatively consistent breakpoints at BP4 and BP5, which include the CHRNA7 gene. About 100 index cases have been reported since the first publication in 2008. This large number of patients ascertained through highly variable samples has been necessary to describe the full phenotypic spectrum of this microdeletion, ranging from mental retardation with dysmorphic features, epilepsy, neuropsychiatric disturbances with or without cognitive impairment to complete absence of anomalies. Here, we describe a collaborative study reporting a new cohort of 12 index patients and 13 relatives carrying a heterozygous BP4-BP5 microdeletion out of a series of 4625 patients screened by array-CGH for DD. We confirm the clinical expressivity of the disease as well as the incomplete penetrance in seven families. We showed through a review of the literature that males are more likely to be symptomatic. Sequence analysis of CHRNA7 yielded no data to support the unmasking of recessive variants as a cause of phenotypic variability. We also report the first patient carrying a 15q13.3 homozygous microdeletion inherited from both parents. He had severe epileptic encephalopathy with retinopathy, autistic features and choreoathetosis. Besides the classical approximately 1.5 Mb BP4-BP5 microdeletion, we also describe three index patients and two relatives with a smaller 500 kb microdeletion, including the CHRNA7 gene.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Adolescente , Pareamento de Bases/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Heterozigoto , Humanos , Padrões de Herança/genética , Masculino , Linhagem , Fenótipo
4.
Phys Rev Lett ; 105(23): 237601, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21231502

RESUMO

The occupation, energy separation, and order of the crystal-field-split 4f states are crucial for the understanding of the magnetic properties of rare-earth systems. We provide the experimental evidence that crystal-field-split 4f states exhibit energy dispersion in momentum space leading to variations of energy spacings between them and even of their energy sequence across the Brillouin zone. These observations were made by performing angle-resolved photoemission experiments on YbRh(2)Si(2) and properly simulated within a simple model based on results obtained by inelastic neutron scattering experiments and band structure calculations. Our findings should be generally applicable to rare-earth systems and have considerable impact on the understanding of magnetism and related phenomena.

5.
Phys Rev Lett ; 104(9): 096402, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20366999

RESUMO

As a homologue to the new, Fe-based type of high-temperature superconductors, the electronic structure of the heavy-fermion compound CeFePO was studied by means of angle-resolved resonant photoemission. It was experimentally found-and later on confirmed by local-density approximation (LDA) as well as dynamical mean-field theory (DMFT) calculations-that the Ce 4f states hybridize to the Fe 3d states of d{3z{2}-r{2}} symmetry near the Fermi level that discloses their participation in the occurring electron-correlation phenomena and provides insight into mechanism of superconductivity in oxopnictides.

6.
Diagn Microbiol Infect Dis ; 90(4): 241-247, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29329757

RESUMO

The accumulation of sequenced Francisella strains has made it increasingly apparent that the 16S rRNA gene alone is not enough to stratify the Francisella genus into precise and clinically useful classifications. Continued whole-genome sequencing of isolates will provide a larger base of knowledge for targeted approaches with broad applicability. Additionally, examination of genomic information on a case-by-case basis will help resolve outstanding questions regarding strain stratification. We report the complete genome sequence of a clinical isolate, designated here as F. novicida-like strain TCH2015, acquired from the lymph node of a 6-year-old male. Two features were atypical for F. novicida: exhibition of functional oxidase activity and additional gene content, including proposed virulence determinants. These differences, which could potentially impact virulence and clinical diagnosis, emphasize the need for more comprehensive methods to profile Francisella isolates. This study highlights the value of whole-genome sequencing, which will lead to a more robust database of environmental and clinical genomes and inform strategies to improve detection and classification of Francisella strains.


Assuntos
Francisella/classificação , Francisella/isolamento & purificação , Genótipo , Linfonodos/microbiologia , Tularemia/diagnóstico , Criança , DNA Bacteriano/química , DNA Bacteriano/genética , Francisella/genética , Genes Bacterianos , Variação Genética , Genoma Bacteriano , Humanos , Masculino , Oxirredutases/genética , Análise de Sequência de DNA , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
7.
J Clin Invest ; 92(1): 404-10, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8326008

RESUMO

Hyperthermia causes changes in expression of TGF-beta mRNA and protein in cultured cardiac cells, as well as in the heart in vivo. 12 h after hyperthermia, primary cultures of neonatal rat cardiomyocytes show a two- to threefold decreased expression of TGF-beta mRNAs which returns to control levels by 48 h after heat shock. In cultures of cardiac fibroblasts, expression of TGF-beta mRNAs increases 5-25-fold, 12-48 h after heat shock, while fetal bovine heart endothelial cells show little change in TGF-beta expression after hyperthermia. In each case, mRNAs for TGF-beta s 1, 2, and 3 are regulated similarly. Hearts isolated from rats exposed to hyperthermia show an initial 20-fold decrease in TGF-beta 1 and 3 mRNA levels which return to control levels by 24 h and subsequently are elevated two- to threefold above normal 48-72 h after heat shock; there is little change in TGF-beta 2 mRNA. Expression of immunoreactive TGF-beta 1 and 3 protein, localized intracellularly in myocytes, follows the same pattern as the mRNA expression. By 72 h, some myocytes show hyperstaining for TGF-beta 1. Staining for extracellular TGF-beta 1/3 exhibits the opposite time course, being most intense 3-6 h after heat shock and returning to control levels by 48 h. The increase in TGF-beta s after hyperthermia could play a role in mediating the reported cardioprotective effects of heat shock.


Assuntos
Temperatura Alta , Miocárdio/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Células Cultivadas , Expressão Gênica , Proteínas de Choque Térmico/genética , Técnicas Imunoenzimáticas , Técnicas In Vitro , RNA Mensageiro/genética , Fator de Crescimento Transformador beta/genética
8.
Genome Announc ; 4(2)2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27013036

RESUMO

Turicibacterbacteria are commonly detected in the gastrointestinal tracts and feces of humans and animals, but their phylogeny, ecological role, and pathogenic potential remain unclear. We present here the first complete genome sequence ofTuricibactersp. strain H121, which was isolated from the feces of a mouse line contaminated following germ-free derivation.

9.
Diabetes Care ; 18(5): 698-700, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-8586011

RESUMO

OBJECTIVE: To emphasis the need for timely diagnosis of Alström syndrome. CASE: We report a case of late-detected Alström syndrome in a boy 15 1/2 years of age who was admitted because of poor wound healing and hyperglycemia. RESULTS: Diagnosis was made and the patient's impaired glucose tolerance improved by diet. CONCLUSIONS: Regular follow-ups are needed to recognize and possibly prevent late-appearing complications.


Assuntos
Surdez/diagnóstico , Intolerância à Glucose , Degeneração Retiniana/diagnóstico , Adolescente , Colesterol/sangue , Diagnóstico Diferencial , Frutosamina , Intolerância à Glucose/dietoterapia , Hemoglobinas Glicadas/análise , Hexosaminas/análise , Humanos , Hiperglicemia , Hipogonadismo , Masculino , Obesidade , Síndrome , Triglicerídeos/sangue , Cicatrização
10.
Genome Announc ; 3(4)2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26272574

RESUMO

The bacterial pathogen Francisella tularensis was recently renewed as a tier-one select agent. F. tularensis subsp. tularensis (type A) and holarctica (type B) are of clinical relevance. Here, we report the complete genome of a virulent F. tularensis type B strain and describe its usefulness in comparative genomics.

11.
FEBS Lett ; 319(3): 212-6, 1993 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-7681409

RESUMO

Occupancy of CD72 on resting tonsillar B cells by monoclonal antibodies (mAb) promotes entry into the G1 phase of the cell cycle with an accompanying increase in MHC Class II expression and provides a co-stimulus to immobilized anti-mu for driving DNA synthesis. We now report that engagement of CD72 by mAb stimulates tyrosine phosphorylation in B cells with a peak of activity seen at 5-10 min. Two major substrates of 29 and 57 kDa showed a basal level of phosphorylation which increased with time, while a 40 kDa protein and several other minor components were phosphorylated de novo on the addition of mAb to CD72. Inositol lipid hydrolysis was found to be unperturbed, although a shallow rise in the basal level of intracellular free Ca2+ was provoked on engaging CD72. Receptor cross-linking was not a requirement for signaling human B cells through CD72: simple occupancy by univalent antibody was sufficient both to trigger the rise in basal [Ca2+]i and to promote DNA synthesis.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos B/metabolismo , Linfócitos B/imunologia , Fosfatos de Inositol/metabolismo , Fosfoproteínas/metabolismo , Tirosina/análogos & derivados , Cálcio/metabolismo , Células Cultivadas , Humanos , Técnicas In Vitro , Peso Molecular , Fosfatidilinositóis/metabolismo , Fosfoproteínas/química , Fosfotirosina , Transdução de Sinais , Tirosina/metabolismo
12.
J Med Chem ; 36(23): 3489-95, 1993 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-8246217

RESUMO

We report a novel conformational search procedure that is used to investigate the binding mechanism of a member of the WIN class of antiviral compounds. A simple hypothesis of important residues in the binding site based on differences in drug-free and drug-bound X-ray structures along with more elaborate models, ultimately including the entire virus, is considered. Our search method is a variant of slow-growth molecular dynamics used in free energy simulations and gives rise to local motion in the protein backbone of up to 3 A. This technique involves the scaling of drug-protein interaction energies over time periods of 10-100 ps and gives rise to local motion in the protein backbone. In addition, we have used high-temperature dynamics with periodic quenching to generate low-energy conformations with backbone displacements in the crystallographic binding region of up to 7 A from the native structure. Mechanism of binding, hydrogen-bond stabilization of active-site conformations, concerted drug-protein motions, and the mode of virion stabilization are addressed in relation to our ligand induced and high-temperature conformational search procedures. A loop-cap like mechanism is consistent with the results of our study. A large movement of the "active-site" residues is shown to be theoretically possible and provides a greater access for entry of the drug into its binding pocket than seen in the available crystal structures.


Assuntos
Antivirais/química , Isoxazóis/química , Sequência de Aminoácidos , Antivirais/metabolismo , Antivirais/farmacologia , Sítios de Ligação , Fenômenos Químicos , Físico-Química , Cristalografia por Raios X , Eletroquímica , Ligação de Hidrogênio , Isoxazóis/metabolismo , Isoxazóis/farmacologia , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular
13.
Am J Med Genet ; 63(1): 223-30, 1996 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-8723114

RESUMO

Conversion of testosterone (T) to dihydrotestosterone (DHT) in genital tissue is catalysed by the enzyme 5 alpha-reductase 2, which is encoded by the SRD5A2 gene. The potent androgen DHT is required for full masculinization of the external genitalia. Mutations of the SRD5A2 gene inhibit enzyme activity, diminish DHT formation, and hence cause masculinization defects of varying degree. The classical syndrome, formerly described as pseudovaginal perineoscrotal hypospadias, is characterized by a predominantly female phenotype at birth and significant virilization without gynecomastia at puberty. We investigated nine patients with steroid 5 alpha-reductase 2 deficiency (SRD). Phenotypes, which were classified according to the severity of the masculinization defect, varied between completely female (SRD type 5), predominantly female (SRD type 4), ambiguous (SRD type 3), predominantly male with micropenis and hypospadias (SRD type 2), and completely male without overt signs of undermasculinization (SRD type 1). T/DHT-ratios were highly increased ( > 50) in the classical syndrome (SRD type 5), but variable in the less severe affected patients (SRD types 1-4) (14-35). Mutations in the SRD5A2 gene had been characterized using PCR-SSCP analysis and direct DNA sequencing. A small deletion was encountered in two patients, while all other patients had single base mutations which result in amino acid substitutions. We conclude that phenotypes may vary widely in patients with SRD5A2 gene mutations spanning the whole range from completely female to normal male without distinctive clinical signs of the disease. Hence, steroid 5 alpha-reductase deficiency should be considered not only in sex reversed patients with female or ambiguous phenotypes, but also in those with mild symptoms of undermasculinization as encountered in patients with hypospadias and/or micropenis. A classification based on the severity of the masculinization defect may be used for correlation of phenotypes with enzyme activities and genotypes, and for comparisons of phenotypes between different patients as the basis for clinical decisions to be made in patients with pseudohermaphroditism due to steroid 5 alpha-reductase 2 deficiency.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/deficiência , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Transtornos do Desenvolvimento Sexual/classificação , Transtornos do Desenvolvimento Sexual/genética , Mutação Puntual , Deleção de Sequência , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Di-Hidrotestosterona/sangue , Feminino , Humanos , Hipospadia/genética , Lactente , Masculino , Pênis/anormalidades , Fenótipo , Testosterona/sangue
14.
J Exp Psychol Gen ; 122(2): 184-94, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8315399

RESUMO

This study examined the responses of a bottlenosed dolphin (Tursiops truncatus) to "normal" (semantically and syntactically correct) sequences of gestures and to anomalous sequences given within an artificial gestural language highly familiar to the animal. Anomalous sequences violated the semantic rules or syntactic constraints of the language. The dolphin discriminated anomalous from normal sequences in that rejections (refusals to respond) occurred to some anomalous sequences but never to normal sequences. Rejections rarely occurred, however, if the anomalous sequence contained a subset of gestures that would comprise a normal unit if joined together. Such units were typically perceived by the dolphin and responded to even if they consisted of gestures that were not sequentially adjacent. All semantic elements of a sequence were processed by the dolphin in relation to other elements before the dolphin organized its final response. The results show the importance of both semantic properties and semantic relations of the referents of the gestures and of syntactic (ordering) constraints in the dolphin's interpretations of the anomalies.


Assuntos
Comunicação Animal , Gestos , Rememoração Mental , Semântica , Animais , Atenção , Feminino , Aprendizagem Seriada
15.
Behav Neurosci ; 101(2): 158-63, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3034301

RESUMO

The role of the temporal order of odor and taste was studied in two experiments, and a third experiment studied the role of odor intensity in flavor-toxicosis conditioning with thirsty rats licking water spouts in a "wind tunnel." In all experiments, odors and tastes were presented for 2 min to rats, and 30 min later, a toxin (lithium chloride) was intubated. In Experiment 1, an odor was presented 90 s before, during, or 90 s after a taste to independent groups. Experiment 2 was a within-subjects partial replication of the first. Each rat was presented with one odor, then a taste, then a second odor with each stimulus separated by 45 s. The results of Experiments 1 and 2 indicated that (a) odor alone is not associated with illness under our conditions, (b) presenting an odor and a taste at the same time potentiates the odor component so that it is associated with illness, (c) 45-s and 90-s intervals between odor and taste eliminate potentiation, and (d) taste and odor interact asymetrically; that is, odor has little affect on the development of taste-illness associations. In Experiment 3, an odor and a taste were presented simultaneously, and odor intensity varied. As odor intensity increased, the strength of the taste-potentiated odor aversion increased, whereas the aversion to the taste remained constant. However, even at the highest intensity, odor presented in the absence of taste did not result in odor aversions.


Assuntos
Aprendizagem da Esquiva , Condicionamento Clássico , Olfato , Paladar , Animais , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Cloretos/toxicidade , Condicionamento Clássico/efeitos dos fármacos , Lítio/toxicidade , Cloreto de Lítio , Masculino , Rememoração Mental/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Olfato/efeitos dos fármacos , Paladar/efeitos dos fármacos
16.
Behav Neurosci ; 102(3): 363-70, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2840092

RESUMO

In five experiments we attempted to establish aversions to a noise presented each time thirsty rats licked a water source. Using an apparatus and a procedure similar to those of previous studies which reported noise-illness associations, weak taste-potentiated noise-illness associations were found (Experiment 1). However, when the apparatus and procedure were varied, noise-illness associations were not observed (Experiments 3, 4, and 5). The noise used in all of these failures was readily associated with shock (Experiment 2), which indicates that this noise was salient to the rats and could be associated with an aversive event. These failures to find noise-illness associations occurred despite the fact that the conditions were chosen to maximize the likelihood of observing these associations. Taste-illness associations always developed normally. The results are consistent with the idea that conditioned aversions to all exteroceptive stimuli are not equally well potentiated by taste.


Assuntos
Aprendizagem por Associação , Aprendizagem da Esquiva , Aprendizagem , Ruído , Paladar , Animais , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Cloretos/toxicidade , Condicionamento Clássico/efeitos dos fármacos , Sinais (Psicologia) , Ingestão de Líquidos/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Lítio/toxicidade , Cloreto de Lítio , Masculino , Ratos , Ratos Endogâmicos , Olfato/efeitos dos fármacos , Paladar/efeitos dos fármacos
17.
Behav Neurosci ; 102(4): 574-9, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3166731

RESUMO

Brattleboro rats are homozygous for diabetes insipidus (HO-DI), lacking the ability to synthesize vasopressin. Besides increasing water consumption, HO-DI rats may compensate for their excessive renal water loss by reducing their intake of and preference for substances that elevate plasma osmolarity. In two experiments we assessed this possibility. In Experiment 1, salt preference of HO-DI and control Long-Evans (LE) rats was measured by presenting the rats with two tubes: one filled with water and the other with NaCl. In the first part of the experiment, 18 NaCl concentrations were presented in increasing order (from 6 to 300 mM). In the second part, other groups of HO-DI and LE rats were presented with 6 concentrations of NaCl, ranging from 6 to 450 mM in either increasing or decreasing order of concentrations. In Experiment 2, preference for 6 concentrations of citric acid ranging from 0.1 to 6 mM was assessed. With NaCl concentrations greater than 100 mM, intake and preference declined rapidly for the HO-DI group but very gradually for the LE group. In contrast, the HO-DI rats preferred all citric acid solutions more than LE rats. The results suggest that HO-DI rats compensate for their inability to concentrate urine not only by increasing water consumption, but also by decreasing consumption of and preference for salty solutions.


Assuntos
Diabetes Insípido/genética , Preferências Alimentares/fisiologia , Hipotálamo/fisiopatologia , Sódio na Dieta/administração & dosagem , Equilíbrio Hidroeletrolítico , Animais , Capacidade de Concentração Renal/efeitos dos fármacos , Masculino , Ratos , Ratos Brattleboro , Ratos Endogâmicos , Solução Salina Hipertônica , Paladar/fisiologia , Vasopressinas/fisiologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
18.
Behav Neurosci ; 104(1): 233-4, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2317282

RESUMO

Taste-potentiated noise aversions have been demonstrated in rats (Ellins, Cramer, & Whitmore, 1985; Ellins & von Kluge, 1987; Holder, Bermudez-Rattoni, & Garcia, 1988). However, these aversions are apparently less readily established than taste-potentiated odor aversions suggesting that all exteroceptive stimuli are not equally well potentiated by taste (Holder et al., 1988). Despite the claims of Ellins, von Kluge, and Cramer (1990), we replicated their findings and see no inconsistency between our findings and theirs. Both sets of results are explained by a common theory of conditioning (Garcia, 1989; Garcia & Holder, 1985).


Assuntos
Condicionamento Clássico , Retroalimentação , Comportamento Alimentar , Paladar , Animais , Aprendizagem da Esquiva , Sinais (Psicologia) , Odorantes , Ratos
19.
Behav Neurosci ; 103(3): 605-11, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2544203

RESUMO

Thirsty male rats were given saccharin water followed by delayed illness. During the delay, some of the rats were exposed to events designed to stimulate their external systems (i.e., the system that processes external events such as auditory and tactile stimulation). Access to females, mild footshocks, and pain from hypertonic saline injections did not interfere with either the acquisition or extinction of a taste aversion. In fact, when administered intraperitoneally, the hypertonic saline slightly increased the strength of the aversion. Exposure to heat, which changed both skin temperature and core temperature, slightly attenuated the formation of the aversion. Overall, these results emphasize the independence of the internal system (i.e., the system that deals with internal events such as taste, illness, and core temperature) and the external system. Furthermore, the associating of events related to the internal system is not readily interfered with by events related to the external system.


Assuntos
Nível de Alerta , Atenção , Aprendizagem da Esquiva , Condicionamento Clássico , Paladar , Animais , Nível de Alerta/efeitos dos fármacos , Aprendizagem por Associação/efeitos dos fármacos , Atenção/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Cloretos/toxicidade , Condicionamento Clássico/efeitos dos fármacos , Eletrochoque , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Feminino , Lítio/toxicidade , Cloreto de Lítio , Masculino , Rememoração Mental/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Comportamento Sexual Animal/efeitos dos fármacos , Paladar/efeitos dos fármacos , Sensação Térmica/efeitos dos fármacos
20.
Ann N Y Acad Sci ; 423: 228-41, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6588788

RESUMO

This paper makes three main points: There are many similarities between man-made rules for detecting causality and "laws" of classical conditioning, presumably generated by nature. They suggest that the function of classical conditioning resembles the detection of causality. There are twelve similarities between the clock used by rats to discriminate time and a stopwatch. They suggest that the rat's clock, like a stopwatch, was designed for measuring unknown durations. There are eight similarities between time discrimination and classical conditions. In particular, whether or not a stimulus is timed depends on the signal value of the stimulus. The similarities suggest that time discrimination and classical conditioning - their underlying mechanisms - have similar functions.


Assuntos
Condicionamento Clássico , Aprendizagem por Discriminação , Percepção do Tempo , Animais , Percepção Auditiva , Extinção Psicológica , Humanos , Ratos , Percepção Visual
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