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1.
Proc Biol Sci ; 289(1976): 20220598, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35703045

RESUMO

Fat-storing hibernators rely on fatty acids from white adipose tissue (WAT) as an energy source to sustain hibernation. Whereas arctic and temperate hibernators preferentially recruit dietary polyunsaturated fatty acids (PUFAs), tropical hibernators can rely on monounsaturated fatty acids that produce fewer lipid peroxides during oxidation. Nevertheless, compositional data on WAT from tropical hibernators are scant and questions remain regarding fat recruitment and metabolism under different environmental conditions. We analyse fatty acid profiles from the WAT of captive dwarf lemurs (Cheirogaleus medius) subjected to high-sugar or high-fat diets during fattening and cold or warm conditions during hibernation. Dwarf lemurs fed high-sugar (compared to high-fat) diets displayed WAT profiles more comparable to wild lemurs that fatten on fruits and better depleted their fat reserves during hibernation. One PUFA, linoleic acid, remained elevated before hibernation, potentially lingering from the diets provisioned prior to fattening. That dwarf lemurs preferentially recruit the PUFA linoleic acid from diets that are naturally low in availability could explain the discrepancy between captive and wild lemurs' WAT. While demonstrating that minor dietary changes can produce major changes in seasonal fat deposition and depletion, our results highlight the complex role for PUFA metabolism in the ecology of tropical hibernators.


Assuntos
Cheirogaleidae , Hibernação , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Ácidos Graxos , Ácidos Graxos Insaturados/metabolismo , Frutas , Ácidos Linoleicos/metabolismo , Açúcares/metabolismo
2.
J Hand Surg Glob Online ; 6(1): 137-139, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38313609

RESUMO

Extensor tendon entrapment in the presence of distal radius fracture is a known but relatively uncommon complication. Single tendon or entire compartment entrapment has been described through the literature in youths and adults. However these findings generally are limited to a certain age demographic or are found on advanced imaging but are unable to be confirmed intraoperatively. We describe to our knowledge the first known description of second extensor compartment entrapment in an adult seen on computerized tomography scan and confirmed intraoperatively.

3.
Heliyon ; 9(8): e18392, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37520952

RESUMO

Climate changes have become undisputed, as have their consequences for global ecosystems and mankind. The coastal areas are among the most affected areas on the planet due to their geographical location. The effects suffered by coastal areas can render the residing populations homeless, as well as compromise the continuity of the history and culture of these environments. The Marine Extractive Reserve of the city of Soure (coastal area of eastern Amazonia) stands out for housing populations that have developed an intimate relationship with nature and have knowledge that can explain people's perception of climate changes. In this context, this study investigated how local residents perceive climate change and its consequences considering different temporal and spatial scales. To this end, questionnaires were developed and applied using a 5-point Likert scale. Our results indicate that perception is shaped by socioeconomic and demographic factors, and that they are perceived on different time scales and geographic space. These findings reflect the awareness-raising efforts of the management body of this Conservation Unit and the local knowledge, derived from the relationship of the residents with the natural environment, which, together, provided the population with assertive information that favor a better understanding of this phenomenon.

4.
Heliyon ; 9(4): e15497, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37151711

RESUMO

The great current challenge for the conservation and use of natural resources refers to global climate change, because of its impacts felt in different intensities at global, regional, and local spatial scales. Within the system of environmental protection areas in Brazil, the extractive reserves ensure the sustainable use of natural resources by traditional populations, thus maintaining the cultural and biological aspects of a region. Such populations, being in close management of the surrounding environments, tend to perceive changes in ecological processes that many need for their livelihoods. The use of this perception of local populations in conjunction with academic research evidence has a high potential to allow a whole and systemic view of possible changes in natural phenomena. This study developed an integrated analysis of scientific evidence and local perceptions to understand the variation of precipitation in a community inserted in an extractive reserve in the eastern Amazon. We used 30 years of precipitation data from the Brazilian National Institute of Meteorology - INMET, the Southern Oscillation Index - SOI, and the Atlantic Meridional Mode Index - AMM. Furthermore, we applied a form to measure the population's perception of possible changes in rainfall cycles in the region. The meteorological data indicate that the region of the community has been presenting a rainfall reduction; however, people in the community do not perceive this trend. Although it is public knowledge that the global climate is undergoing changes, a fact noted after the integrating analysis of scientific evidence with local knowledge in Resexmar Soure is that the perceptions of traditional populations often focus on smaller temporal and spatial scale visions.

5.
Behav Processes ; 200: 104685, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35690289

RESUMO

Remembering the past appears critical in allowing organisms to detect order in an environment, and hence to behave in accordance with likely future events. Yet the shortcomings of remembering and perceiving typically mean that the remembered past differs from the actual past, and hence that behavior does not perfectly track the structure of the environment. Here, we outline how the process of generalization might be used to understand differences between what an organism does, and the structure of the past and potential structure of the environment. We explore how different sources of generalization - both from within the same stimulus situation, and from different stimulus situations - might be modeled quantitatively, and how predictions made by this modeling approach are supported by research. Finally, we discuss how generalization from multiple stimulus situations, longer-term experience, and from stimulus situations in the past that are not identical to the stimulus situation in the present, might contribute to our understanding of how an organism's experience translates into behavior.


Assuntos
Generalização Psicológica , Rememoração Mental , Generalização do Estímulo
6.
Osteoporos Int ; 21(11): 1899-909, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19967337

RESUMO

UNLABELLED: Our objective was to assess the association of self-reported non-persistence (stopping fracture-prevention medication for more than 1 month) and self-reported non-compliance (missing doses of prescribed medication) with perceived need for fracture-prevention medication, concerns regarding long-term harm from and/or dependence upon medications, and medication-use self-efficacy (confidence in one's ability to successfully take medication in the context of their daily life). INTRODUCTION: Non-persistence (stopping medication prematurely) and non-compliance (not taking medications at the prescribed times) with oral medications to prevent osteoporotic fractures is widespread and attenuates their fracture reduction benefit. METHODS: Cross-sectional survey and medical record review of 729 patients at a large multispecialty clinic in the United States prescribed an oral bisphosphonate between January 1, 2006 and March 31, 2007. RESULTS: Low perceived necessity for fracture-prevention medication was strongly associated with non-persistence independent of other predictors, but not with non-compliance. Concerns about medications were associated with non-persistence, but not with non-compliance. Low medication-use self-efficacy was associated with non-persistence and non-compliance. CONCLUSIONS: Non-persistence and non-compliance with oral bisphosphonate medication have different, albeit overlapping, sets of predictors. Low perceived necessity of fracture-prevention medication, high concerns about long-term safety of and dependence upon medication , and low medication-use self-efficacy all predict non-persistence with oral bisphosphonates, whereas low medication-use self-efficacy strongly predicts non-compliance with oral bisphosphonate medication. Assessment of and influence of these medication attitudes among patients at high risk of fracture are likely necessary to achieve better persistence and compliance with fracture-prevention therapies.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Adesão à Medicação/psicologia , Fraturas por Osteoporose/prevenção & controle , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Osteoporose/tratamento farmacológico , Pacientes Desistentes do Tratamento/psicologia , Autoeficácia , Fatores Socioeconômicos , Adulto Jovem
8.
J Clin Invest ; 65(2): 390-9, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6965379

RESUMO

Factors influencing basophil production from the bone marrow of ovalbumin (OA)-sensitized guinea pigs have been examined in vitro. Autologous co-cultures of marrow and spleen cells from OA-immune animals contained significantly higher numbers of basophils after 7 d of liquid culture in the presence of OA, compared with control co-cultures or with marrow cultures alone (P < 0.005). Basophils increased in co-culture as the number of spleen cells added to a fixed number of marrow cells was increased from 0.10 to 2.5 x 10(6)/ml; at each spleen cell concentration, the presence of OA significantly enhanced basophil production in vitro when compared with unstimulated co-cultures. There was no basophil production from spleen cell suspensions cultured in the absence of autologous marrow cells. Conditioned media (CM) prepared from OA-stimulated spleen cells of OA-treated animals (CM-OA) caused a specific stimulation of basophil production from normal guinea pig bone marrow cells in liquid cultures (P < 0.01). Phytohemagglutinin (PHA)- and pokeweed mitogen-stimulated CM (CM-PHA, CM-pokeweed mitogen) nonspecifically enhanced normal basophilopoiesis, causing dose-dependent increases in basophils and histamine in vitro. CM-OA and CM-PHA also preferentially stimulated formation of neutrophil-macrophage colony-forming units in semisolid methylcellulose cultures.CM-PHA prepared from T cell-enriched splenic cell suspensions contained basophil-stimulating activity, whereas T cell-depleted CM-PHA activity did not exceed control values (P < 0.01). Preliminary characterization of CM-PHA revealed that basophil-stimulating activity was predominantly heat stable and nondialyzable. These results demonstrate OA-specific, as well as mitogen-dependent T-cell regulation of guinea pig basophilopoiesis in vitro. The data are compatible with the existence of a specific "basophilopoietin" in CM derived from guinea pig splenic T cells.


Assuntos
Basófilos/citologia , Hematopoese , Linfócitos T/fisiologia , Animais , Células da Medula Óssea , Comunicação Celular , Ensaio de Unidades Formadoras de Colônias , Meios de Cultura , Cobaias , Histamina/análise , Técnicas In Vitro , Mitógenos/farmacologia , Ovalbumina/imunologia , Fito-Hemaglutininas/farmacologia , Baço/citologia
9.
Cochrane Database Syst Rev ; (3): CD006291, 2007 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-17636839

RESUMO

BACKGROUND: Local anaesthesia for cataract surgery can be provided by either sub-Tenon or topical anaesthesia. Although there is some work suggesting advantages to both techniques, there has been no recent systematic attempt to compare both techniques for all relevant outcomes. OBJECTIVES: To compare the effectiveness of topical anaesthesia (with or without the addition of intracameral local anaesthetic) and sub-Tenon's anaesthesia in providing pain relief during cataract surgery. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2006, Issue 2); MEDLINE (1990 to July 2006); EMBASE (1990 to July 2006) and reference lists of articles. There were no constraints based on language or publication status. SELECTION CRITERIA: We included all randomized or quasi-randomized studies comparing sub-Tenon anaesthesia with topical anaesthesia for cataract surgery. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We also collected adverse effects information from the trials. MAIN RESULTS: Seven studies involving 617 patients with 742 eyes operated on were examined. Five studies used unpaired data, with a single eye operated on; two studies used paired data with both eyes operated on. The surgical technique was clear corneal incision in five studies and scleral tunnel in two. The overall quality of the studies was not high, with one study triple blind (patient, surgeon and assessor blinded to treatment group) and three others single blind. The allocation of concealment and methods of randomization were only described in two studies. Three unpaired studies showed that sub-Tenon anaesthesia provided better intra-operative pain relief than topical anaesthesia (pooled weighted mean difference (fixed) 1.28, 95% CI 0.83to 1.72). The differences in the pain scores are not necessarily clinically significant although statistically significant. The differences are not large in magnitude and are skewed to the low end of the visual analogue scale but the studies are consistent throughout in reporting more pain in the topical anaesthesia group. This was also supported by the one paired study which showed that the mean pain score in the topical group was 1.13 (SD 1.57) compared with 0.57 (SD 1.28) in the sub-Tenon group (P < 0.001). Three of the studies used a 10-point visual analogue scale, while one used a novel 5-point scale. Further support was provided by other outcome measures. Sub-Tenon anaesthesia caused more chemosis and sub-conjunctival haemorrhage although this was purely aesthetic. The more serious complication of posterior capsule tear and vitreous loss occurred twice as much in the topical group than with sub-Tenon anaesthesia (4.3% versus 2.1%). AUTHORS' CONCLUSIONS: Sub-Tenon anaesthesia provides better pain relief than topical anaesthesia for cataract surgery.


Assuntos
Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Extração de Catarata , Bloqueio Nervoso/métodos , Adulto , Anestesia Local/efeitos adversos , Humanos , Dor/etiologia , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Bone Joint J ; 99-B(3): 358-364, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28249976

RESUMO

AIMS: To investigate the bone penetration of intravenous antibiotic prophylaxis with flucloxacillin and gentamicin during hip and knee arthroplasty, and their efficacy against Staphylococcus (S.) aureus and S. epidermidis. PATIENTS AND METHODS: Bone samples from the femoral head, neck and acetabulum were collected from 18 patients undergoing total hip arthroplasty (THA) and from the femur and tibia in 21 patients during total knee arthroplasty (TKA). The concentration of both antibiotics in the samples was analysed using high performance liquid chromatography. Penetration was expressed as a percentage of venous blood concentration. The efficacy against common infecting organisms was measured against both the minimum inhibitory concentration 50, and the more stringent epidemiological cutoff value for resistance (ECOFF). RESULTS: The bone penetration of gentamicin was higher than flucloxacillin. Relative to ECOFF, flucloxacillin concentrations were effective against S. aureus and S. epidermidis in all THAs and 20 (95%) TKAs. Gentamicin concentrations were effective against S. epidermidis in all bone samples. Gentamicin was effective against S. aureus in 11 (61.1%) femoral neck samples in THA. Effective concentrations of gentamicin against S. aureus were only achieved in four (19%) femoral and six (29%) tibial samples in TKA. CONCLUSION: Flucloxacillin and gentamicin were found to penetrate bone during THA and TKA. Gentamicin was effective against S. epidermidis in both THA and TKA, while levels were subtherapeutic against S. aureus in most TKAs. Bone penetration of both antibiotics was less in TKA than THA, and may relate to the use of a tourniquet. Using this antibiotic combination, effective cover against the two common infective organisms was achieved in all THAs and all but one TKA. Cite this article: Bone Joint J 2017;99-B:358-64.


Assuntos
Antibacterianos/farmacocinética , Floxacilina/farmacocinética , Gentamicinas/farmacocinética , Prótese de Quadril/efeitos adversos , Prótese do Joelho/efeitos adversos , Infecções Relacionadas à Prótese/prevenção & controle , Acetábulo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Antibioticoprofilaxia/métodos , Artroplastia de Quadril , Artroplastia do Joelho , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Fêmur/metabolismo , Floxacilina/administração & dosagem , Gentamicinas/administração & dosagem , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus , Staphylococcus epidermidis/efeitos dos fármacos , Tíbia/metabolismo
11.
BMJ Open ; 6(6): e010672, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27288373

RESUMO

OBJECTIVE: Urgent care centres' (UCCs) hours were developed with the aim of reducing inappropriate emergency department (ED) attendances in England. We aimed to examine the presenting complaint and outcomes of care in 2 general practitioner (GP)-led UCCs with extended opening times. DESIGN: Retrospective observational epidemiological study using routinely collected data. SETTING: 2 GP-led UCCs in London, colocated with a hospital ED. PARTICIPANTS: All children aged under 5 years, attending 2 GP-led UCCs over a 3-year period. OUTCOMES: Outcomes of care for the children including: primary diagnosis; registration status with a GP; destination following review within the UCC; and any medication prescribed. Comparison between GP-led UCC visit rates and routine general practices was also made. RESULTS: 3% (n=7747/282 947) of all attenders at the GP-led UCCs were children aged under 5 years. The most common reason for attendance was a respiratory illness (27%), followed by infectious illness (17%). 18% (n=1428) were either upper respiratory tract infections or viral infections. The majority (91%) of children attending were registered with a GP, and over two-thirds of attendances were 'out of hours'. Overall 79% were seen and discharged home. Preschool children were more likely to attend their GP (47.0 per 100) than a GP-led UCC (9.4 per 100; 95% CI 8.9 to 10.0). CONCLUSIONS: Two-thirds of preschool children attending GP-led UCCs do so out of hours, despite the majority being registered with a GP. The case mix is comparable with those presenting to an ED setting, with the majority managed exclusively by the GPs in the UCC before discharge home. Further work is required to understand the benefits of a GP-led urgent system in influencing future use of services especially emergency care.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Clínicos Gerais , Pré-Escolar , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Modelos Lineares , Londres , Masculino , Estudos Retrospectivos
12.
J Invest Dermatol ; 101(3): 305-9, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8370966

RESUMO

Antileukoprotease is known to be an antiproteolytic compound of mucous secretions in humans. While searching for peptide-like inhibitors of neutrophil-derived serine proteases in horny layers of human skin, we isolated a potent inhibitor of human leukocyte elastase (EC 3.4.21.37) and cathepsin G (EC 3.4.21.20) from psoriatic scales. This inhibitor showed inhibitory constants for human leukocyte elastase of approximately 0.5-2 x 10(-10) M and for cathepsin G of 2-4 x 10(-9) N. The N-terminal amino acid sequence of the purified peptide matched the sequence of antileukoprotease and both peptides showed the same M(r) on SDS-PAGE. Therefore, antileukoprotease may not only regulate serine protease activities in mucous secretions, but also in skin.


Assuntos
Proteínas , Psoríase/metabolismo , Inibidores de Serina Proteinase/análise , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Proteínas Secretadas Inibidoras de Proteinases , Pele/química
13.
FEBS Lett ; 262(2): 327-9, 1990 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-2335214

RESUMO

The multicatalytic proteinase complex is a high molecular weight nonlysosomal proteinase which is composed of many different types of subunit. As part of a study of the possible relationships between subunits, polypeptides derived from the multicatalytic proteinase from rat liver have been subjected to N-terminal amino acid sequence analysis. Although several of the subunits are blocked at their N-termini, sequences have been obtained for 7 of the polypeptides. Each of the 7 sequences is unique but they show considerable sequence similarity, suggesting that the proteins are encoded by members of the same gene family.


Assuntos
Cisteína Endopeptidases/genética , Fígado/enzimologia , Complexos Multienzimáticos/genética , Família Multigênica , Sequência de Aminoácidos , Animais , Dados de Sequência Molecular , Complexo de Endopeptidases do Proteassoma , Conformação Proteica , Ratos
14.
Proc Biol Sci ; 265(1410): 2095-9, 1998 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-9842736

RESUMO

Biased sex ratios of young of birds and mammals clearly occur and may have an adaptive significance, but we rarely know the stage at which a bias is generated, or the mechanism. If a bias is generated prior to birth, studies of marsupials may be insightful because gestation is short and neonates are relatively undifferentiated. This study investigated whether biased sex ratios in Antechinus agilis are generated in the brief period between birth and the attachment of young to the mother's teats. When all young born, or just pouch young, or supernumerary young were considered, litters were strongly biased towards females (0.32 males), and there was no significant difference across the groups, so a bias is generated before birth in this species. Evidence from counts of corpora lutea suggests that embryo loss during gestation cannot account fully for the level of bias observed. Therefore, prefertilization mechanisms must contribute to the generation of sex-biased litters in this marsupial.


Assuntos
Marsupiais/fisiologia , Razão de Masculinidade , Animais , Corpo Lúteo/fisiologia , Feminino , Tamanho da Ninhada de Vivíparos , Masculino , Marsupiais/genética , Processos de Determinação Sexual
15.
Am J Cardiol ; 68(15): 1498-502, 1991 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1746433

RESUMO

Transesophageal contrast echocardiography is an effective but semiinvasive technique for the detection of interatrial right-to-left shunts. Transcranial Doppler ultrasound is an alternative noninvasive method, but may be limited by false-positive diagnoses due to intrapulmonary shunting. This study examined the accuracy of transcranial Doppler for the detection of shunt lesions. Transcranial Doppler of the right middle cerebral artery was performed simultaneously with transesophageal and transthoracic contrast echocardiography in 32 patients using agitated saline contrast during normal respiration and Valsalva. Transesophageal contrast echocardiography diagnosed an interatrial right-to-left shunt in 13 patients and intrapulmonary shunting in 6 patients. Transcranial Doppler identified all 13 interatrial right-to-left shunts and an intrapulmonary shunt in 3 of 6 patients. Absence of a shunt was confirmed by transcranial Doppler in 12 of 12 patients. Transcranial Doppler had a sensitivity of 100% (13 of 13), specificity of 100% (18 of 18) and accuracy of 100% (31 of 31) for prediction of an interatrial right-to-left shunt by transesophageal contrast echocardiography. In comparison, transthoracic contrast echocardiography had a sensitivity of 54% (7 of 13), specificity of 94% (17 of 18) and accuracy of 77% (24 of 31). Thus, transcranial Doppler is highly accurate for detection of an interatrial right-to-left shunt and not compromised by physiologic intrapulmonary shunts, whereas transthoracic contrast echocardiography lacks sensitivity. Transcranial Doppler may be useful as an alternative to transesophageal study, where the primary indication for transesophageal echocardiography is exclusion of an interatrial right-to-left shunt.


Assuntos
Artérias Cerebrais/diagnóstico por imagem , Ecocardiografia , Comunicação Interatrial/diagnóstico por imagem , Adulto , Idoso , Ecocardiografia/métodos , Esôfago , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Tórax
16.
Curr Probl Cardiol ; 17(2): 73-137, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1735241

RESUMO

The first step towards the diagnosis of cardiac neoplasia is made when the clinician considers the diagnosis. While the classically described signs and symptoms of left-atrial myxomas are noteworthy, the vast majority of patients present with symptomatology that is less specific--either of a constitutional nature, or related to right- or left-sided congestion. Likewise, the physical examination may rarely disclose classic auscultatory signs, but is more likely to confirm the presence of the right- or left-sided congestion inferred from history. Peripheral, embolic, or vasculitis lesions should raise suspicion of the diagnosis. Nevertheless, the majority of patients will be diagnosed by the unexpected detection of a tumor at the time of echocardiography. Transthoracic echocardiography remains the procedure of choice in screening for cardiac neoplasia. It has excellent sensitivity for intracavitary and endocardial lesions. Myocardial lesions are also well imaged. Pericardial lesions, with or without extension into contiguous structures, are poorly visualized and, here, magnetic resonance imaging is unquestionably the superior investigative approach. Further, a limited degree of tissue characterization is possible with the latter technology. Transesophageal echocardiography is ideally suited for the examination of suspected tumors involving the atria, interatrial septum, superior vena cava, atrioventricular valves and, to a lesser extent, the ventricles. These three imaging modalities clearly complement one another and the choice of application will depend upon factors including the patient's transthoracic echogenicity, the availability of magnetic resonance imaging or transesophageal echocardiography, cost, and the physical status of the patient.


Assuntos
Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/terapia , Angiocardiografia , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Testes de Função Cardíaca , Neoplasias Cardíacas/secundário , Humanos , Imageamento por Ressonância Magnética , Mixoma/diagnóstico , Fonocardiografia , Radiografia Torácica , Tomografia Computadorizada por Raios X
17.
Psychopharmacology (Berl) ; 50(2): 149-52, 1976 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-826954

RESUMO

Intravenous administration of epinephrine results in a dose-dependent inhibition of the peripherally evoked electrodermal response (EDR) in the cat. The magnitude of this depression of the EDR was greater when the responses were evoked by a single shock than by a train of shocks (10-12 Hz). The observation that this epinephrine-induced inhibition is antagonized by phentolamine suggests that an alpha-adrenergic mechanism is involved. It is unlikely that this effect is due primarily to the vascular actions of epinephrine because the inhibition of the EDR was much more prolonged than was the pressor action. Angiotensin was ineffective in inhibiting these responses.


Assuntos
Epinefrina/farmacologia , Resposta Galvânica da Pele/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Gatos , Estimulação Elétrica , Epinefrina/antagonistas & inibidores , Resposta Galvânica da Pele/fisiologia , Fentolamina/farmacologia
18.
Eur J Pharmacol ; 68(2): 193-6, 1980 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-7202486

RESUMO

The action of indoramin on central autonomic activity was investigated using the sympathetic-cholinergic electrodermal response system. Indoramin (0.33-10 mg/kg, i.v.) significantly reduced the amplitude of electrodermal responses (EDR) evoked by stimulation of the hypothalamus in a dose-related manner. The CNS effects of indoramin on the EDR were partially antagonized by yohombine pretreatment. These results demonstrate that indoramin reduces central sympathetic reactivity and suggest that an alpha-adrenergic inhibitory mechanism may be involved.


Assuntos
Encéfalo/efeitos dos fármacos , Indóis/farmacologia , Indoramina/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Encéfalo/fisiologia , Gatos , Relação Dose-Resposta a Droga , Feminino , Masculino , Sistema Nervoso Simpático/fisiologia , Ioimbina/farmacologia
19.
Eur J Pharmacol ; 37(1): 71-8, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-1278247

RESUMO

Electrodermal responses (EDR) were evoked centrally by stimulation of reactive loci in the posterior hypothalamus and peripherally by stimulation of the distal portion of the sectioned median or ulnar nerve. Moderate doses of clonidine (3-30 mug/kg, i.v.) reduced the amplitude of the centrally evoked EDR while having no effect on the peripherally evoked responses. This central action of clonidine occurred concomitantly with the clonidine-induced bradycardia and hypotension. Administration of clonidine shifted the centrally evoked EDR frequency-response curve to the right in a dose related manner at 3, 10 and 30 mu/kg, i.v. 1 mug/kg was without effect on these responses. This central depressant action of clonidine was partially reversed following administration of yohimbine (0.5-1.0 mug/kg, i.v.). These results suggest that clonidine inhibits central reactivity in this sympathetic-cholinergic system in a manner analogous to its action on other sympathetic systems, and that a central adrenergic inhibitory mechanism may be involved.


Assuntos
Clonidina/farmacologia , Resposta Galvânica da Pele/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Gatos , Clonidina/antagonistas & inibidores , Estimulação Elétrica , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hipotálamo/fisiologia , Masculino , Modelos Neurológicos , Nervos Periféricos/fisiologia , Ioimbina/farmacologia
20.
J Exp Psychol Anim Behav Process ; 10(3): 390-409, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6747556

RESUMO

An analogue of the human yes-no detection task was used to train six pigeons to discriminate luminance differences under two different reinforcer-scheduling procedures. When a controlled reinforce-ratio procedure was used, relative stimulus frequency was constant at .5, and relative reinforcer frequency for correct detections was held constant at three different values for each of five luminance differences. When an uncontrolled reinforcer-ratio procedure (the typical detection paradigm) was used, relative reinforcer frequency for correct detections was allowed to covary with changes in relative stimulus frequency for each of five luminance differences. Two measures of bias, response bias (Davison & Tustin, 1978) and the detection-theory likelihood-ratio measure (beta obt), were compared. The controlled reinforcer-ratio procedure generated equal- or iso-response-bias functions, and the uncontrolled reinforcer-ratio procedure gave changing or alloio-response-bias functions. The Davison-Tustin model accounted for 88% and 93% of the data variance in the controlled and uncontrolled reinforcer-ratio procedures, respectively. The best-fitting equal-beta functions accounted for an average of 53% and 69%, respectively, in the two procedures. In addition, neither procedure gave constant measures of beta obt for constant bias manipulations across different discriminability measures.


Assuntos
Aprendizagem por Discriminação , Percepção Visual , Animais , Columbidae , Psicofísica , Esquema de Reforço
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