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Permafrost and methane hydrates are large, climate-sensitive old carbon reservoirs that have the potential to emit large quantities of methane, a potent greenhouse gas, as the Earth continues to warm. We present ice core isotopic measurements of methane (Δ14C, δ13C, and δD) from the last deglaciation, which is a partial analog for modern warming. Our results show that methane emissions from old carbon reservoirs in response to deglacial warming were small (<19 teragrams of methane per year, 95% confidence interval) and argue against similar methane emissions in response to future warming. Our results also indicate that methane emissions from biomass burning in the pre-Industrial Holocene were 22 to 56 teragrams of methane per year (95% confidence interval), which is comparable to today.
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BACKGROUND: Little is known about resource use in the care of neuroendocrine tumors (NETs). This study defined patterns of costs in NET management and compared them with those of a more common malignancy, colon cancer (CC). METHODS: Using a provincial cancer registry (2004-2012), NET patients were identified and matched at a ratio of 1-3 with CC patients. Four phases of care were examined: pre-diagnostic (PreDx: -2 years to -181 days), diagnostic (Dx: -180 days to +180 days), postdiagnostic (PostDx: +181 days to +3 years), and prolonged post-diagnostic (PPostDx: +181 days to +9 years). The mean costs per patient were compared, and cost predictors were analyzed with quintile regression. RESULTS: Of 3827 NETs, 3355 were matched with 9320 CCs. The PreDx mean NET costs were higher than the CC costs ($5877 vs $5368; p = 0.06), driven by nondrug costs. They were lower in the Dx and PostDx phases (both p < 0.01). For PPostDx, the drug costs were higher for NETs ($26,788 vs $7827; p < 0.01), representing 41% of the costs versus 16% of the costs for CC. Older age and comorbidities predicted higher NET costs in all phases. Lower socioeconomic status (SES) predicted higher costs in the initial phases and higher SES costs in the PPost-Dx phase. Gastroenteric NETs were associated with lower costs in the Dx phase [parameter estimate (PE), -$13,644] and pancreatic NETs with higher costs in PostDx phase (PE, $3348). CONCLUSION: Currently, NETs represent a potential important health care burden. The NET cost patterns differed from those for CC, with the highest costs during the PPostDx phase. The SES and primary NET site affected costs differently at different time points. These data can inform resource allocation tailored to the needs for NETs.
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Neoplasias do Colo/economia , Pesquisa Comparativa da Efetividade/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Recursos em Saúde/economia , Tumores Neuroendócrinos/economia , Adulto , Idoso , Canadá/epidemiologia , Estudos de Coortes , Neoplasias do Colo/epidemiologia , Neoplasias do Colo/terapia , Comorbidade , Análise Custo-Benefício , Feminino , Seguimentos , Custos de Cuidados de Saúde/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/terapia , Prognóstico , Sistema de RegistrosRESUMO
OBJECTIVE: Significant life events such as severe health status changes or intensive medical treatment often trigger response shifts in individuals that may hamper the comparison of measurements over time. Drawing from the Oort model, this study aims at detecting response shift at the item level in psychosomatic inpatients and evaluating its impact on the validity of comparing repeated measurements. STUDY DESIGN AND SETTING: Complete pretest and posttest data were available from 1188 patients who had filled out the ICD-10 Symptom Rating (ISR) scale at admission and discharge, on average 24 days after intake. Reconceptualization, reprioritization, and recalibration response shifts were explored applying tests of measurement invariance. In the item-level approach, all model parameters were constrained to be equal between pretest and posttest. If non-invariance was detected, these were linked to the different types of response shift. RESULTS: When constraining across-occasion model parameters, model fit worsened as indicated by a significant Satorra-Bentler Chi-square difference test suggesting potential presence of response shifts. A close examination revealed presence of two types of response shift, i.e., (non)uniform recalibration and both higher- and lower-level reconceptualization response shifts leading to four model adjustments. CONCLUSIONS: Our analyses suggest that psychosomatic inpatients experienced some response shifts during their hospital stay. According to the hierarchy of measurement invariance, however, only one of the detected non-invariances is critical for unbiased mean comparisons over time, which did not have a substantial impact on estimating change. Hence, the use of the ISR can be recommended for outcomes assessment in clinical routine, as change score estimates do not seem hampered by response shift effects.
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Nível de Saúde , Pacientes Internados/psicologia , Transtornos Psicofisiológicos/psicologia , Qualidade de Vida/psicologia , Perfil de Impacto da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
Reducing cardiac mortality and improving quality of life are the main objectives of cardiac rehabilitation. In recent years, outpatient rehabilitation within easy patient reach has achieved the same status as inpatient rehabilitation. Outpatient rehabilitation permits close involvement of the patient's family and social environment, thus easing reintegration into everyday life. However, the health care system is not yet utilizing outpatient rehabilitation to its full potential. This contribution illustrates the principles of rehabilitation following myocardial infarction or for heart failure in an outpatient setting, as well as its potential and future development.
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Assistência Ambulatorial/tendências , Insuficiência Cardíaca/reabilitação , Infarto do Miocárdio/reabilitação , Admissão do Paciente/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/economia , Terapia Combinada , Redução de Custos/tendências , Feminino , Previsões , Alemanha , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/mortalidade , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Programas Nacionais de Saúde/economia , Programas Nacionais de Saúde/tendências , Admissão do Paciente/economia , Prognóstico , Qualidade de Vida , Centros de Reabilitação/economia , Centros de Reabilitação/tendências , Comportamento de Redução do Risco , Ajustamento SocialRESUMO
BACKGROUND: In the last 2 decades there has been a large increase in publications on complementary and alternative medicine (CAM). However, CAM research methodology was heterogeneous and often of low quality. The aim of this systematic review was to investigate scientific publications with regards to general issues, concepts and strategies. We also looked at research priorities and methods employed to evaluate the clinical and epidemiological research of CAM in the past to identify the basis for consensus-based research strategies. METHODS: We performed a systematic literature search for papers published between 1990 and 2010 in 7 electronic databases (Medline, Web of Science, PsychArticles, PsycInfo, CINAHL, EMBASE and Cochrane Library) on December 16 and 17, 2010. In addition, experts were asked to nominate relevant papers. Inclusion criteria were publications dealing with research methodology, priorities or complexities in the scientific evaluation of CAM. All references were assessed in a multistage process to identify relevant papers. RESULTS: From the 3,279 references derived from the search and 98 references contributed by CAM experts, 170 papers fulfilled the criteria and were included in the analysis. The following key issues were identified: difficulties in past CAM research (e.g., randomisation, blinding), utility of quantitative and qualitative research methods in CAM, priority setting in CAM research and specific issues regarding various CAM modalities. CONCLUSIONS: Most authors vote for the use of commonly accepted research methods to evaluate CAM. There was broad consensus that a mixed methods approach is the most suitable for gathering conclusive knowledge about CAM.
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Pesquisa Biomédica/organização & administração , Terapias Complementares/organização & administração , Comparação Transcultural , Projetos de Pesquisa Epidemiológica , Pesquisa Biomédica/estatística & dados numéricos , Terapias Complementares/estatística & dados numéricos , Europa (Continente) , Humanos , Apoio à Pesquisa como Assunto/organização & administração , Apoio à Pesquisa como Assunto/estatística & dados numéricosRESUMO
Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen & Löwenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2-10 ml, 20-100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error +/-SD was 3.5 +/- 2.6% (2-10 ml) and 5.9 +/- 0.7% (20-60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F(i)O(2) caused the measured tidal volume to increase by up to 25% (F(i)O(2) = 1.0). The relative error +/- SD of the leak measurements was -0.2 +/- 11.9%. For leaks > 19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F(i)O(2) > 0.4 and for leaks > 19%, a numerical correction of the displayed volume should be performed.
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Pressão Positiva Contínua nas Vias Aéreas/instrumentação , Volume de Ventilação Pulmonar , Ventiladores Mecânicos/normas , Algoritmos , Pressão Positiva Contínua nas Vias Aéreas/métodos , Humanos , Umidade , Recém-Nascido , Monitorização Fisiológica/instrumentação , Ventilação Pulmonar , Testes de Função Respiratória/instrumentação , Mecânica RespiratóriaRESUMO
At the Austrian Research Centers Seibersdorf (ARCS), a whole body counter (WBC) in the scan geometry is used to perform routine measurements for the determination of radioactive intake of workers. The calibration of the WBC is made using bottle phantoms with a homogeneous activity distribution. The same calibration procedures have been simulated using Monte Carlo N-Particle (MCNP) code and FLUKA and the results of the full energy peak efficiencies for eight energies and five phantoms have been compared with the experimental results. The deviation between experiment and simulation results is within 10%. Furthermore, uncertainty budget evaluations have been performed to find out which parameters make substantial contributions to these differences. Therefore, statistical errors of the Monte Carlo simulation, uncertainties in the cross section tables and differences due to geometrical considerations have been taken into account. Comparisons between these results and the one with inhomogeneous distribution, for which the activity is concentrated only in certain parts of the body (such as head, lung, arms and legs), have been performed. The maximum deviation of 43% from the homogeneous case has been found when the activity is concentrated on the arms.
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Modelos Biológicos , Método de Monte Carlo , Exposição Ocupacional/análise , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Contagem Corporal Total/instrumentação , Contagem Corporal Total/métodos , Algoritmos , Carga Corporal (Radioterapia) , Calibragem , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Internacionalidade , Modelos Estatísticos , Exposição Ocupacional/prevenção & controle , Imagens de Fantasmas , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , SoftwareRESUMO
The present work which was carried out in the framework of an EU project (IDEA: Internal Dosimetry-Enhancements in Application; Contract Number: FIKR CT2001 00164) shall provide commonly acceptable guidelines for optimum performance of ICP-MS measurements with focus on urinary measurements of uranium, thorium and actinides. From the results of this work it is recommended that, whenever feasible, 24 h urine sampling should be conducted to avoid large uncertainties in the quantitation of daily urinary excretion values. For storage, urine samples should be acidified and kept frozen before analysis. Measurement of total uranium in urine by ICP-MS at physiological levels (<10 ng.l(-1)) requires no sample preparation besides UV photolysis and/or dilution. For the measurement of thorium in urine by ICP-MS, it can be concluded, that salt removal from the urine samples is not recommended. For the measurement of actinides in urine it is shown that ICP-MS is well-suited and a good alternative to alpha-spectrometry for isotopes with T1/2>5x10(4) years. In general, ICP-MS measurements are an easy, fast and cost-saving methodology. New improved measuring techniques (HR-SF-ICP-MS) with detection limits in urine of 150 pg.l(-1) (1.9 microBq.l(-1)) for 238U, 30 pg.l(-1) (2.4 microBq.l(-1)) for 235U and 100 pg.l(-1) (0.4 microBq.l(-1)) for (232)Th, respectively, meet all necessary requirements. This method should therefore become the routine technique for incorporation monitoring of workers and of members of the general public, in particular for uranium contamination.
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Algoritmos , Bioensaio/métodos , Exposição Ambiental/análise , Modelos Biológicos , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Radioisótopos/análise , Radioisótopos/farmacocinética , Simulação por Computador , Humanos , Internacionalidade , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeAssuntos
Vestuário/efeitos adversos , Corantes/efeitos adversos , Medição de Risco , Têxteis/efeitos adversos , Adulto , Compostos Azo/efeitos adversos , Criança , Quitosana/efeitos adversos , Corantes/normas , Testes Imunológicos de Citotoxicidade , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , União Europeia , Polímeros de Fluorcarboneto/efeitos adversos , Alemanha , Humanos , Internet , Testes para Micronúcleos , Modelos Teóricos , Nanotecnologia , Sistema de Registros , Pesquisa , Testes Cutâneos , Indústria Têxtil , Têxteis/normasRESUMO
Hepatic steatosis together with lactic acidosis is a life threatening side effect in HIV infected patients receiving highly active antiretroviral therapy (HAART). We describe 5 patients developing hepatic drug toxicity during longterm treatment with nucleoside reverse transcriptase inhibitors. The main clinical symptoms included abdominal pain, fever, and neurological disorders. Serum lactate levels were elevated leading to severe metabolic acidosis in 3 cases. Liver biopsies revealed extensive macro- and microvesicular steatosis. Mitochondrial alterations were detected by electronmicroscopy. Microvesicular steatosis was seen in one case with elevated liver enzymes, but normal serum lactate levels, and was most extensive in a patient with a severe lactic acidotic coma. We conclude that detection of microvesicular steatosis and mitochondrial alterations in liver biopsies may help to identify the development of a nucleoside induced hepatopathy before the onset of severe lactic acidosis.
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Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Fígado Gorduroso/induzido quimicamente , Infecções por HIV/tratamento farmacológico , Inibidores da Transcriptase Reversa/efeitos adversos , Acidose/induzido quimicamente , Acidose/patologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/patologia , Adulto , Fígado Gorduroso/patologia , Feminino , Infecções por HIV/induzido quimicamente , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
In view of follow up, survey and development of therapeutic strategies for osteoarthritis where cartilage deterioration plays an important role, a non invasive, reliable and quantitative assessment of the articular cartilage is desirable. The currently available high resolution T(1)-weighted (T1-w) 3D FLASH pulse sequences with frequency selective fat suppression are very time consuming. We have 1) optimized a high resolution T1-w 3D FLASH water excitation (WE) sequence for short acquisition time and cartilage visualization, and 2) validated this sequence for cartilage volume and thickness quantification. The spectral fat presaturation was replaced by selective water excitation. The flip angle of the WE sequence was optimized for the contrast to noise (C/N(cart)) ratio of cartilage. Sagittal datasets (voxel size: 0.31 x 0.31 x 2 mm(3)) of the knees of nine healthy volunteers were acquired both, with the 3D FLASH WE (17.2/6.6/30 degrees ) sequence (WE) and a previously validated 3D FLASH fat saturated (42/11/30 degrees ) sequence (FS). For validation of the WE sequence, cartilage volume, mean and maximal cartilage thickness of the two sequences were compared. Reproducibility was assessed by calculating the coefficient of variation (COV %) of 4 consecutive WE data sets in the volunteers. The acquisition time was reduced from 16'30" (FS) down to 7'14" for the WE sequence. Image contrast and visualization of the cartilage was very similar, but delineation of the basal layer of the cartilage was slightly improved with the WE sequence. A flip angle of 30 degrees provided the best C/N(cart) ratios (WE). Reproducibility (COV) was between 1.9 and 5.9%. Cartilage volume and thickness agreed within 4% between FS and WE sequence. The WE sequence allows for rapid, valid and reproducible quantification of articular cartilage volume and thickness, prerequisites for follow-up examinations. The reduced acquisition time (50% of FS) enables routine clinical application and thus may contribute to a broader assessment of osteoarthritis.
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Cartilagem Articular/patologia , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Adulto , Idoso , Feminino , Análise de Fourier , Humanos , Articulação do Joelho/patologia , Masculino , Pessoa de Meia-Idade , Análise Numérica Assistida por Computador , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/cirurgia , Reprodutibilidade dos TestesRESUMO
The purpose of this study was to compare liver contrast-enhancing characteristics of two superparamagnetic reticuloendothelial system (RES)-directed agents with different particle sizes, polycrystalline iron oxide nanocompounds (PION) and carboxydextran-coated maghemite (DDM128N/389, later referred to as DDM128), in an experimental model of focal radiation-induced hepatitis. PION, for the small particle size (31 nm), and DDM128, for the large particle size (59 nm), RES-directed agents were compared for liver enhancement after radiation-induced liver injury. A single x-irradiation exposure varying from 10 to 60 Gy was delivered to one side of the liver. T2-weighted spinecho magnetic resonance imaging was performed 3 days after x-irradiation at 30 minutes post-contrast. Using the RES-directed PION, the normal, non-irradiated portion of the liver decreased in signal intensity with a maximum negative enhancement of -66%, while the irradiated portion of the liver decreased in signal intensity by -24% (60 Gy). The signal intensity decline of irradiated liver tissue using PION was dose dependent, but was found at all radiation dose levels (10-60 Gy). The difference in signal intensity between irradiated (-63%) and non-irradiated (-82%) portions was also statistically different using DDM128 at 60 Gy. However, lower irradiation doses (10 and 30 Gy) failed to produce a statistically significantly different enhancement in the irradiated and non-irradiated portion of the liver. Sensitivity of liver enhancement with RES-directed agents is size dependent. The smaller particle (PION) is more sensitive for detection of radiation-induced hepatitis than the larger particle (DDM128). The relative insensitivity of DDM128 enhancement for diffuse liver injury will be clinically advantageous for detecting focal lesions in the presence of diffuse hepatic injury.
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Meios de Contraste , Hepatite Animal/patologia , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Lesões Experimentais por Radiação/patologia , Animais , Compostos Férricos , Hepatite Animal/etiologia , Aumento da Imagem , Ferro , Fígado/efeitos da radiação , Masculino , Óxidos , Tamanho da Partícula , Pós , Ratos , Ratos Sprague-DawleyRESUMO
PURPOSE: This pilot study evaluated potential relationships between dental status and various sociodemographic variables in the age group segment of the United States population at greatest risk for the disruption of dental function due to treatment of an oral cavity cancer. METHODS: The Dental Health Supplement of the 1989 National Health Interview Survey was used to evaluate the self-reported status of natural dentition and prior dental rehabilitation among the population of persons 45 years or older. RESULTS: Sociodemographic variables, which showed a significant association with status of natural dentition, were level of income and occupation at lower income levels (p < 0.05). Increased levels of prior dental rehabilitation were significantly associated with lower age, female gender, increased level of income, and occupation (p < 0.05). Occupations that required social interaction had the highest levels of both status of natural dentition and prior dental rehabilitation (p < 0.05). CONCLUSIONS: Overall dental status after treatment of oral cancer may be related to the occupational status of many persons. Sociodemographic factors that influence the dental rehabilitation needs of individual patients after treatment of an oral cancer should be considered in policy decisions affecting accessibility of dental rehabilitative care. A follow-up, survey study that would further define the identified relationships between a person's demographic status and dental rehabilitation needs is recommended.
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Prótese Dentária/estatística & dados numéricos , Boca Edêntula/epidemiologia , Perda de Dente/epidemiologia , Fatores Etários , Idoso , Atitude Frente a Saúde , Demografia , Inquéritos de Saúde Bucal , Emprego , Feminino , Avaliação Geriátrica , Necessidades e Demandas de Serviços de Saúde , Humanos , Renda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Boca Edêntula/reabilitação , Projetos Piloto , Fatores de Risco , População Rural , Fatores Sexuais , Inquéritos e Questionários , Perda de Dente/reabilitação , Estados Unidos/epidemiologia , População UrbanaRESUMO
We describe a low-cost telepathology system working via a commercial integrated services digital network (ISDN) and consisting of modular software and hardware elements. The main elements are Apple Macintosh workstations; a software program for the simultaneous transfer of pictures, voice, and data; and procedures for image processing and general administration of all the information generated. Additionally, the system allows remote control of any peripheral instruments by a "picture-instrument manager." The transfer rate is currently 64 kbit/s; it will be extended to 128 kbit/s (ISDN basic rate) in the near future and to 2 Mbit/s (ISDN primary rate) in the next 2 years. The system was tested by the regional hospital in Samedan, Switzerland, and the Department of Pathology, University of Basel, Basel, Switzerland, a distance of 250 km, by offering a remote frozen section service to the regional hospital in 16 cases. Fifty-four to 58 seconds were needed for the transfer of a diagnostic 8-bit grey-level image containing 341 (median value) +/- 26.1 (standard error) kbytes (n = 13) or a diagnostic 24-bit color image containing 165 (median value) +/- 16.9 (standard error) kbytes (n = 3). The time required for a diagnostic session was between 25 and 35 minutes.
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Redes de Comunicação de Computadores/instrumentação , Neoplasias/diagnóstico , Telemedicina/normas , Adulto , Idoso , Diagnóstico por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Sensibilidade e Especificidade , Suíça , Telemedicina/economia , Fatores de TempoRESUMO
We studied the psycho-social circumstances of HIV-positive women and their children, who were born between January 1, 1984 and June 30, 1991 and are being treated at the Department of Pediatrics. We interviewed 19 women out of 21 families using the problem-centered interview technique according to Witzel. 29 out of 30 children were older than 18 months. Four children were HIV-positive and the serology of one patient aged 12 months who had been perinatally exposed was yet unclarified. The study showed massive problems within these families, such as considerable partner problems, drug abuse and social isolation. Furthermore, there was a lack of child care to relieve the mothers. The predominance of drug problems and insufficient experience of social institutions with the problematic nature of HIV-infection in mothers and children require more efficient preventive measures.
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Filho de Pais com Deficiência/psicologia , Soropositividade para HIV/psicologia , Meio Social , Fatores Socioeconômicos , Criança , Pré-Escolar , Feminino , Soropositividade para HIV/congênito , Soropositividade para HIV/transmissão , Humanos , Lactente , Recém-Nascido , Masculino , Casamento/psicologia , Poder Familiar/psicologia , Desenvolvimento da Personalidade , Assistência Pública , Papel do Doente , Pais Solteiros/psicologia , Ajustamento SocialAssuntos
Serviços Centralizados no Hospital , Administração Hospitalar , Departamentos Hospitalares/estatística & dados numéricos , Serviço Hospitalar de Radiologia/estatística & dados numéricos , Apoio à Pesquisa como Assunto , Equipamentos e Provisões Hospitalares , Docentes de Medicina , New York , Estados UnidosRESUMO
In deciding to use a new intravascular contrast medium, the considerations should be patient safety, Imaging efficacy, and cost. Balancing these factors, use can be estimated. With the new low-osmolality contrast media, particularly the nonionic media, the expected increased patient safety must be balanced against the much higher cost.