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1.
Sci Total Environ ; 878: 162957, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36958545

RESUMO

In the 1960s, the Quintero industrial complex was inaugurated in Chile. This began a history of dramatic anthropogenic impacts on the Chilean coast. Among the known, we could mention high atmospheric emissions of chemicals due to combustion processes and frequent oil spills. For this reason, we surveyed the concentrations of fifteen EPAPAHs in the surface coastal waters of the Quintero Bay area in 2015. The levels found are in the range of the highest levels when reviewing the literature (0.97 µg L-1 up to 9.84 µg L-1). The highest levels were found in the vicinity of the industrial complex and decreased in the other two zones. The concentration of individual compounds significantly exceeds the levels recommended by the EPA (Environmental Protection Agency) and the EU water framework directive (WFD). The risk estimations revealed that PAH concentrations represent high-risk for wildlife. Molecular ratios of PAHs were used to identify the possible sources, being these were mainly of pyrogenic origin, agreeing with an origin in the combustion of wood, coal, grass, and fossil fuels. This study contributes to the first data for surface water in a country's highly impacted industrial coastal area.

2.
Zootaxa ; 4981(2): 357364, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34186716

RESUMO

The last instar larva of Micrathyria paulsoni González-Soriano, 2020 is described and illustrated in detail based on specimens collected in Veracruz State, Mexico. It is compared with the larvae of M. didyma (Selys in Sagra, 1857) and M. hypodidyma Calvert, 1906, all of them belonging into the "Micrathyria didyma" group. The main structural features of M. paulsoni larva are 910 long premental setae plus 45 small setae, palpal setae 10, legs banded, a large, submedian, dark spot on each side of a pale middorsal line on S69, S89 with a posterolateral spine, larger in S9.


Assuntos
Odonatos/anatomia & histologia , Odonatos/classificação , Animais , Larva , México
3.
Med Phys ; 48(1): 19-56, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32392626

RESUMO

BACKGROUND: Geant4 is a Monte Carlo code extensively used in medical physics for a wide range of applications, such as dosimetry, micro- and nanodosimetry, imaging, radiation protection, and nuclear medicine. Geant4 is continuously evolving, so it is crucial to have a system that benchmarks this Monte Carlo code for medical physics against reference data and to perform regression testing. AIMS: To respond to these needs, we developed G4-Med, a benchmarking and regression testing system of Geant4 for medical physics. MATERIALS AND METHODS: G4-Med currently includes 18 tests. They range from the benchmarking of fundamental physics quantities to the testing of Monte Carlo simulation setups typical of medical physics applications. Both electromagnetic and hadronic physics processes and models within the prebuilt Geant4 physics lists are tested. The tests included in G4-Med are executed on the CERN computing infrastructure via the use of the geant-val web application, developed at CERN for Geant4 testing. The physical observables can be compared to reference data for benchmarking and to results of previous Geant4 versions for regression testing purposes. RESULTS: This paper describes the tests included in G4-Med and shows the results derived from the benchmarking of Geant4 10.5 against reference data. DISCUSSION: Our results indicate that the Geant4 electromagnetic physics constructor G4EmStandardPhysics_option4 gives a good agreement with the reference data for all the tests. The QGSP_BIC_HP physics list provided an overall adequate description of the physics involved in hadron therapy, including proton and carbon ion therapy. New tests should be included in the next stage of the project to extend the benchmarking to other physical quantities and application scenarios of interest for medical physics. CONCLUSION: The results presented and discussed in this paper will aid users in tailoring physics lists to their particular application.


Assuntos
Benchmarking , Física , Radiometria , Simulação por Computador , Método de Monte Carlo
5.
Appl Radiat Isot ; 114: 154-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27235889

RESUMO

A Bonner sphere spectrometer was used to measure the neutron spectra produced at the collision of protons with an H2(18)O target at different angles. A unique H2(18)O target to produce (18)F was designed and placed in a Tandem linear particle accelerator which produces 8.5MeV protons. The neutron count rates measured with the Bonner spheres were unfolded with the MAXED code. With the GEANT4 Monte Carlo code the neutron spectrum induced in the (p, n) reaction was estimated, this spectrum was used as initial guess during unfolding. Although the cross section of the reaction (18)O(p,n)(18)F is well known, the neutron energy spectra is not correctly defined and it is necessary to verify the simulation with measurements. For this reason, the sensitivity of the unfolding method to the initial spectrum was analyzed applying small variation to the fast neutron peak.

6.
Am J Psychiatry ; 155(4): 530-5, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9546000

RESUMO

OBJECTIVE: The aim of this research was to study the relationship between the clinical interview skills of primary care physicians and their psychodiagnostic ability during office visits. METHOD: Ten doctors took part in the study, and 233 patients were assessed. The patients were seen and diagnosed by their physicians and interviewed afterward by a psychiatrist using the Present State Examination. All the interviews with the primary care physicians were recorded on videotape, and the Physician's Skills Observation Scale was used to analyze 10 interviews per doctor, five psychiatric cases and five nonpsychiatric cases. RESULTS: The physician's active listening (eye contact, posture, and absence of verbal interruptions) and ability to ask questions with psychological content were associated with the ability to identify the patient's emotional problems. This association was shown to be independent of the physician's characteristics (social, academic, attitudinal, and professional), the sociodemographic characteristics of the patients, the time spent in exploration during the office visit, and the severity of the emotional or somatic disorder. CONCLUSIONS: The findings of this research highlight the need to train primary care physicians in specific interview skills, in order to improve their ability to identify mental disorders in their practices.


Assuntos
Competência Clínica/normas , Medicina de Família e Comunidade/normas , Transtornos Mentais/diagnóstico , Médicos de Família/normas , Escalas de Graduação Psiquiátrica/normas , Adulto , Idoso , Atitude do Pessoal de Saúde , Escolaridade , Medicina de Família e Comunidade/educação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Comunicação não Verbal , Visita a Consultório Médico , Relações Médico-Paciente , Médicos de Família/educação , Postura , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Índice de Gravidade de Doença , Fatores de Tempo , Gravação de Videoteipe
7.
Arch Clin Neuropsychol ; 14(7): 581-92, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14590572

RESUMO

This article presents a theoretical and methodological framework that seeks to integrate multiple sources of pertinent data that must be taken into account to interpret neuropsychological test results of individuals of non-European ancestry. It is proposed that cultural factors have a determining influence on an individual's behavior regardless of the neurophysiological status of the brain. A differentiation is made between the effects of culture/language and socioeconomic level on cognitive testing results and suggestions are made to assist in discriminating between these variables. Taking as illustration the assessment of Latino patients, focus is given to the accurate neuropsychological evaluation of individuals with little education, of non-European cultures, and with a primary language other than English.

8.
Clin Rheumatol ; 16(2): 154-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9093797

RESUMO

A multicentre, double-blind, randomised, parallel group study was undertaken to investigate the efficacy and safety of aceclofenac (123 patients, 100 mg twice daily) in comparison to piroxicam (117 patients, 20 mg once daily and placebo once daily) in patients with osteoarthritis of the knee. The treatment period of two months was preceded by a washout period of one week duration. On completion of the study, patients in both aceclofenac and piroxicam-treated groups exhibited significant improvement in pain intensity and functional capacity of the affected knee, as represented by the Osteoarthritis Severity Index (OSI) (p < 0.0001 and p < 0.001 respectively). This was further substantiated following the patient's assessment of pain intensity using the Visual Analogue Scale (VAS), in which significant improvements were demonstrated at all time points for each treatment group (p < 0.001). Although both treatment groups showed a significant improvement in all investigator's clinical assessments (functional exploration of the knee, knee flexion and extension (EXT)), there were no significant differences between the groups. There was, however, a more rapid improvement in knee flexion in the aceclofenac group after 15 days of treatment. Both aceclofenac and piroxicam were well tolerated by patients, the most commonly reported adverse events being gastrointestinal, although their incidence was low. Only 24 patients on aceclofenac, as opposed to 33 on piroxicam complained of dyspepsia, epigastralgia and pyrosis. While 7 patients in each group were withdrawn because of adverse events, only one patient with piroxicam was withdrawn because of severe upper gastrointestinal bleeding. Twice as many reports of fecal blood loss were made in the piroxicam group in comparison to the aceclofenac group. In summary, this study confirms the therapeutic efficacy of aceclofenac and suggests that it is a well-tolerated alternative NSAID to piroxicam in the treatment of osteoarthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Diclofenaco/análogos & derivados , Osteoartrite/tratamento farmacológico , Piroxicam/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diclofenaco/uso terapêutico , Método Duplo-Cego , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor
9.
Sci Total Environ ; 302(1-3): 267-74, 2003 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-12526915

RESUMO

Romans, Jews, Arabs and Christians built the ancient city of Toledo (Spain) with bricks as the main construction material. Manganese micro-nodules (circa 2 microm in diameter) have grown under the external bio-film surface of the bricks. Recent anthropogenic activities such as industrial emissions, foundries, or traffic and housing pollution have further altered these old bricks. The energy-dispersive X-ray microanalyses (XPS) of micro-nodules show Al, Si, Ca, K, Fe and Mn, with some carbon species. Manganese atoms are present only as Mn(4+) and iron as Fe(3+) (FeOOH-Fe(2)O(3) mixtures). The large concentration of alga biomass of the River Tagus and the Torcón and Guajaraz reservoirs suggest manganese micro-nodules are formed either from water solutions rich in anthropogenic MnO(4)K in a reduction environment (from Mn(7+) to Mn(4+)) or by oxidation mechanisms from dissolved Mn(2+) (from Mn(2+) to Mn(4+)) linked to algae biofilm onto the ancient brick surfaces. Ancient wall surfaces were also studied by scanning electron microscopy (SEM-EDS) and X-ray diffraction (XRD). Chemical and biological analyses of the waters around Toledo are also analysed for possible sources of manganese. Manganese micro-nodules on ancient brick walls are good indicators of manganese pollution.


Assuntos
Materiais de Construção , Poluentes Ambientais/análise , Eucariotos , Manganês/análise , Biomassa , Microscopia Eletrônica de Varredura , Oxirredução , Espanha
10.
Artigo em Inglês | MEDLINE | ID: mdl-15147684

RESUMO

The spectral properties of Na2SO4 have been studied by means of infrared stimulated luminescence (IRSL), thermoluminescence (TL) and radioluminescence (RL) in the range of 200-800 nm. The observed changes in the RL emission spectra after an annealing treatment (400 degrees C for 1 h) could be linked to thermal phase transformations and alkali self-diffusion through the lattice of this salt. Despite the complexity of the luminescence spectra structure, five emission bands peaked at 330, 345, 385, 460 and 630 nm could be distinguished. The UV-blue TL emission of this material exhibits a maximum peaked at 230 degrees C which is well correlated with the differential thermal analysis (DTA) and can be associated with the thermal transformation of the orthorhombic sodium sulphate (Na2SO4) V (thenardite) phase into Na2SO4 III, II and I phases. Taking into account the observed changes on the structural phase transition by X-ray diffraction (XRD) from 16 degrees C onwards, this material does not show satisfactory features for radiation dosimetry, but could be employed for temperature calibration of TL readers.


Assuntos
Sulfatos/química , Cristalização , Cristalografia por Raios X , Luminescência , Microscopia Eletrônica de Varredura , Espectrofotometria , Sulfatos/efeitos da radiação , Temperatura , Termodinâmica
11.
J Psychoactive Drugs ; 25(1): 35-44, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8097765

RESUMO

Cocaine abuse has created widespread problems, especially in poor urban ethnic minority communities. This article discusses the cultural issues in delivering a cocaine treatment program to a predominantly minority patient population. The Stimulant Treatment Outpatient Program (STOP) of San Francisco General Hospital's Substance Abuse Services was established in 1990 as a public service clinic. Many program elements apply equally well to various cultural groups, including individual and group counseling, limited time in treatment, and crisis intervention. Culturally linked clinical issues include provision of a supportive infrastructure, role models in leadership positions, understanding the cultural influences in patients' lives, and establishing communication links with Cultural themes are discussed as they apply to treating African-Americans, Latinos, Asian-Americans, Native Americans, and clients of different genders. Programmatic outcome indicators, including program attrition, suggest that different cultural groups benefit differentially from the treatment.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Estimulantes do Sistema Nervoso Central , Cultura , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Feminino , Humanos , Masculino , Transtornos Relacionados ao Uso de Substâncias/psicologia
12.
Arch Latinoam Nutr ; 46(1): 38-41, 1996 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-9161458

RESUMO

Bilateral ovariectomies (OVX) or sham surgeries-respectively-were performed in two lots of ten female Wistar rats, 90 days old. Food was available ad libitum to sham rats, and it was restricted to OVX ones. At 15, 30, 45 and 90 days, a segment of their tails was sectioned. At 180 days all rats were sacrificed and the left femurs were excised. With the tail's bones and the femurs we determined Ca++, PO4(-3), Mg++ y Na+ concentration. After 15 days, no significant differences inter lots were observed (p < 0.05) in all ions contents. After 30 days Ca++ value was significantly less (p < 0.05) in the OVX rats than in the sham ones. After 45 days all the analyzed OVX rats ions were significantly less (p < 0.05) than the sham values. That difference inter lots was greater after 90 days. Finally, day 180th gave a decrease in the OVX rat values-from the femur-as follows: for Ca++ 31%, for PO4(-3) 29%, for Mg++ 31.6% and for Na+ 29%. Our results shown that in 90 days old ovariectomized rats, the concentration of calcium, phosphate, magnesium and sodium in the tail bones is a good indicator of bone mass loss, after 45 days of ovariectomy.


Assuntos
Osso e Ossos/química , Cálcio/análise , Magnésio/análise , Ovariectomia , Fosfatos/análise , Sódio/análise , Animais , Peso Corporal , Feminino , Osteoporose/diagnóstico , Ratos , Ratos Wistar , Fatores de Tempo
13.
J Instrum ; 82013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23750176

RESUMO

A positron emission mammograph (PEM) is an organ dedicated positron emission tomography (PET) scanner for breast cancer detection. State-of-the-art PEMs employing scintillating crystals as detection medium can provide metabolic images of the breast with significantly higher sensitivity and specificity with respect to standard whole body PET scanners. Over the past few years, crystal PEMs have dramatically increased their importance in the diagnosis and treatment of early stage breast cancer. Nevertheless, designs based on scintillators are characterized by an intrinsic deficiency of the depth of interaction (DOI) information from relatively thick crystals constraining the size of the smallest detectable tumor. This work shows how to overcome such intrinsic limitation by substituting scintillating crystals with pixelated CdTe detectors. The proposed novel design is developed within the Voxel Imaging PET (VIP) Pathfinder project and evaluated via Monte Carlo simulation. The volumetric spatial resolution of the VIP-PEM is expected to be up to 6 times better than standard commercial devices with a point spread function of 1 mm full width at half maximum (FWHM) in all directions. Pixelated CdTe detectors can also provide an energy resolution as low as 1.5% FWHM at 511 keV for a virtually pure signal with negligible contribution from scattered events.

14.
Nutr Hosp ; 27(1): 270-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22566333

RESUMO

OBJECTIVE: To determine the trend of high school students from Valparaíso Chile by means of an anthropometrical somatotype. MATERIAL AND METHODS: two samples of students during the years 1984-1985 (86 men and 71 women) and 2009-2010 (77 men and 86 women) between 15 and 18 years of age have been studied. Somatotype was estimated by the Heath-Carter anthropometric method. RESULTS: significant differences were found in all the variables of the somatotype during the periods studied (p < 0.01), except for height (p = 0.176) and humeral breadth in women (p = 0.067). Important distinctions were also found in the endomorphic, mesomorphic and ectomorphic components (p < 0.01). Men measurements registered remarkable differences in all the variables (p < 0.01), with the exception of weight (p = 0.156), calf breadth (p = 0.906) and arm breadth in contraction (p = 0.284). Measurement results of endomorphic (p < 0.01), ectomorphic (p < 0.01) and mesomorfic components (p < 0.05) revealed considerable differences. During the period 1984-1985, men classified as balanced mesomorph 2.7-4.8-3.1 which switched to mesomorph-endomorph 3.8-4.3-2.5 in the period 2009-2010. And the population of women in the 1984-1985 period is classified as mesomorph-endomorph 4.2-4.7-2.1 and changes to a mesomorphic-endomorph biotype 6.6-4.1-1.3 in the 2009-2010. CONCLUSIONS: the somatotype of the adolescent population, especially women in Valparaiso, Chile has changed to a predominant endomorphic biotype, and its mesomorphic component has decreased. A high relative adiposity contributes to increase the probability for these people to suffer non-transmissible chronic diseases and cardiovascular issues.


Assuntos
Somatotipos/fisiologia , Adiposidade/fisiologia , Adolescente , Antropometria , Braço/anatomia & histologia , Estatura/fisiologia , Peso Corporal/fisiologia , Chile/epidemiologia , Feminino , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Caracteres Sexuais , Dobras Cutâneas , Estudantes
15.
Phys Med Biol ; 56(1): 273-88, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21149946

RESUMO

Monte Carlo-based modelling is a powerful tool to help in the design and optimization of positron emission tomography (PET) systems. The performance of these systems depends on several parameters, such as detector physical characteristics, shielding or electronics, whose effects can be studied on the basis of realistic simulated data. The aim of this paper is to validate a comprehensive study of the Raytest ClearPET small-animal PET scanner using a new Monte Carlo simulation platform which has been developed at CIEMAT (Madrid, Spain), called GAMOS (GEANT4-based Architecture for Medicine-Oriented Simulations). This toolkit, based on the GEANT4 code, was originally designed to cover multiple applications in the field of medical physics from radiotherapy to nuclear medicine, but has since been applied by some of its users in other fields of physics, such as neutron shielding, space physics, high energy physics, etc. Our simulation model includes the relevant characteristics of the ClearPET system, namely, the double layer of scintillator crystals in phoswich configuration, the rotating gantry, the presence of intrinsic radioactivity in the crystals or the storage of single events for an off-line coincidence sorting. Simulated results are contrasted with experimental acquisitions including studies of spatial resolution, sensitivity, scatter fraction and count rates in accordance with the National Electrical Manufacturers Association (NEMA) NU 4-2008 protocol. Spatial resolution results showed a discrepancy between simulated and measured values equal to 8.4% (with a maximum FWHM difference over all measurement directions of 0.5 mm). Sensitivity results differ less than 1% for a 250-750 keV energy window. Simulated and measured count rates agree well within a wide range of activities, including under electronic saturation of the system (the measured peak of total coincidences, for the mouse-sized phantom, was 250.8 kcps reached at 0.95 MBq mL(-1) and the simulated peak was 247.1 kcps at 0.87 MBq mL(-1)). Agreement better than 3% was obtained in the scatter fraction comparison study. We also measured and simulated a mini-Derenzo phantom obtaining images with similar quality using iterative reconstruction methods. We concluded that the overall performance of the simulation showed good agreement with the measured results and validates the GAMOS package for PET applications. Furthermore, its ease of use and flexibility recommends it as an excellent tool to optimize design features or image reconstruction techniques.


Assuntos
Método de Monte Carlo , Tomografia por Emissão de Pósitrons/métodos , Animais , Simulação por Computador , Processamento de Imagem Assistida por Computador/métodos , Camundongos , Modelos Biológicos , Tomografia por Emissão de Pósitrons/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Electrophoresis ; 21(5): 1018-25, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10768789

RESUMO

The analysis described in this contribution is focused on the effect of Joule heating generation on the hydrodynamics of batch electrophoretic cells (i.e., cells that do not display a forced convective term in the motion equation). The hydrodynamics of these cells is controlled by the viscous forces and by the buoyancy force caused by the temperature gradients due to the Joule heating generation. The analysis is based on differential models that lead to analytical and/or asymptotic solutions for the temperature and velocity profiles of the cell. The results are useful in determining the characteristics of the temperature and velocity profiles inside the cell. Furthermore, the results are excellent tools to be used in the analysis of the dispersive-mixing of solute when Joule heating generation must be accounted for. The analysis is performed by identifying two sequentially coupled problems. Thus, the "carrier fluid problem" and the "solute problem" are outlined. The former is associated with all the factors affecting the velocity profile and the latter is related to the convective-diffusion aspects that control the spreading of the solute inside the cell. The analysis of this contribution is centered on the discussion of the "carrier fluid problem" only. For the boundary conditions selected in the contribution, the study leads to the derivation of an analytical temperature and a "universal" velocity profile that feature the Joule heating number. The Grashof number is a scaling factor of the actual velocity profile. Several characteristics of these profiles are studied and some numerical illustrations have been included.


Assuntos
Impedância Elétrica , Eletroforese , Temperatura Alta , Matemática , Fenômenos Físicos , Física , Termodinâmica
18.
Electrophoresis ; 21(5): 1026-33, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10768790

RESUMO

This contribution addresses the problem of solute dispersion in a free convection electrophoretic cell for the batch mode of operation, caused by the Joule heating generation. The problem is analyzed by using the two-problem approach originally proposed by Bosse and Arce (Electrophoresis 2000, 21, 1018-1025). The approach identifies the carrier fluid problem and the solute problem. This contribution is focused on the latter. The strategy uses a sequential coupling between the energy, momentum and mass conservation equations and, based on geometrical and physical assumptions for the system, leads to the derivation of analytical temperature and velocity profiles inside the cell. These results are subsequently used in the derivation of the effective dispersion coefficient for the cell by using the method of area averaging. The result shows the first design equation that relates the Joule heating effect directly to the solute dispersion in the cell. Some illustrative results are presented and discussed and their implication to the operation and design of the device is addressed. Due to the assumptions made, the equation may be viewed as an upper boundary for applications such as free flow electrophoresis.


Assuntos
Impedância Elétrica , Eletroforese , Temperatura Alta , Difusão , Matemática , Fenômenos Físicos , Física , Termodinâmica
19.
Int J Addict ; 29(9): 1189-99, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7960312

RESUMO

Six papers were presented in the course of a 2-day symposium on the topic of Latinas and Substance Use. The individuals invited to present included established as well as evolving female investigators within the fields of indigenous peoples' psychology, sociology, and ethnography. Methodology used in the studies ranged from epidemiological telephone surveys to ethnographic observations. What made this conference unique and exciting in the first place was that a select group of female researchers, who have as the focus of their investigations substance use patterns in Latino populations, were gathered together for 2 days to listen, process, and discuss the Latina experience as it relates to her profile of substance use, abuse, and her response to substance use and abusing patterns within her family and community. Topics of investigations included depth of HIV knowledge among adolescent Latinas, prevalence of protective practices of Latinas when engaging in high-risk behaviors, and childhood experiences of Latinas who exhibit extremely deviant behaviors. All of the studies had as a primary background substance-using practices primarily related to alcohol use and abuse. In her literature review Canino states that alcohol consumption is multiply influenced or determined by the community's perception of this behavior, accessibility to the substance, physiological tolerance, demographic variables, and ethnic and subcultural group characteristics. The papers presented in one way or another substantiate and support this perspective. The present critique raises a number of questions about what may constitute culturally sensitive research methodology, the confounds in the interpretation of acculturation as a unitary concept, and the troubling issues and conflicts raised by what is perceived as an imperative to preserve cultural traditions.


Assuntos
Alcoolismo/epidemiologia , Hispânico ou Latino/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Alcoolismo/psicologia , Criança , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Infecções por HIV/transmissão , Hispânico ou Latino/psicologia , Humanos , Incidência , Masculino , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/psicologia , Estados Unidos/epidemiologia
20.
Int J Lepr Other Mycobact Dis ; 59(4): 605-12, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1802943

RESUMO

NIH mice infected with Mycobacterium lepraemurium (MLM) show a marked depression in their levels of hemolytic complement that is proportional to the degree of infection. The defect affects more the activation of complement through the classical pathway (CPW) than the activation of complement through the alternative pathway. Although this low activity of CPW-complement may be due to different causes (complement consumption by the infecting microorganism, lack of biosynthesis of complement components, or the presence of complement inhibitory factors), our results seem to support the last possibility. The generation of factors in the infected animals that inhibit the autologous activity of complement as the infection goes on reduces the risk of complement-mediated tissue damage and prolongs the survival time of the host, a wise strategy on the part of the MLM to assure its own survival as a parasite.


Assuntos
Proteínas Inativadoras do Complemento/imunologia , Via Alternativa do Complemento , Via Clássica do Complemento , Infecções por Mycobacterium/imunologia , Mycobacterium lepraemurium/imunologia , Animais , Complexo Antígeno-Anticorpo/sangue , Feminino , Soros Imunes/imunologia , Rim/imunologia , Camundongos , Proteinúria/urina
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