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Results of a thirty-year follow-up of a clinical trial of chemo-hormonal therapy are reported. Eligible patients had recently diagnosed operable breast cancer, positive lymph nodes, no previous history of cancer, age less than 76 years, and no evidence of metastatic disease. A total of 311 patients were stratified by estrogen receptor (ER) status and number of axillary nodes involved with tumor. After stratification, patients were randomly assigned to one of three treatment regimens: cyclophosphamide, methotrexate and 5-fluorouracil (CMF) for 1 year; CMF chemotherapy combined with anti-estrogen therapy (tamoxifen) for 1 year; or CMF plus tamoxifen with BCG during the second year. The endpoint of the trial was a first recurrence. Factors measured at diagnosis and used in the analyses were age, body mass index, ER status, menopausal status, number of positive nodes, tumor diameter, Charlson comorbidity index, socioeconomic status, and race. Causes of death and incidence of other cancer primaries were obtained from death certificates and medical records. Patients treated with tamoxifen had a marginally longer disease-free survival (hazard ratio (HR)=0.83, 95% CI identical with [0.66, 1.04]) and statistically significant longer overall survival (HR=0.77, 95% CI identical with [0.63, 0.96]) that decreased with time. Incidence of other primary cancers and causes of death were similar for the two treatment groups. The addition of 1 year of tamoxifen to CMF therapy provides an early disease-free and overall survival advantage; however long-term effects are negligible. Similarly, the survival advantage of patients diagnosed with ER+ tumors persists for the first two decades after diagnosis.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Moduladores de los Receptores de Estrógeno/uso terapéutico , Metástasis Linfática/patología , Factores de Edad , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Terapia Combinada , Ciclofosfamida/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Mastectomía Segmentaria , Metotrexato/administración & dosificación , Posmenopausia , Premenopausia , Receptores de Estrógenos/metabolismo , Análisis de Supervivencia , Tamoxifeno/administración & dosificaciónRESUMEN
The incidence of hepatocellular carcinoma has been rising in the USA in the past two decades. Hepatocellular carcinoma primarily affects older people and reaches its highest prevalence among those aged between 50 and 70 years. Chronic infection by the hepatitis B virus is the most common cause of this disease. Since hepatocellular carcinoma is an indolent tumor, it has a low life expectancy. In patients with suspected hepatocellular carcinoma, CT, MRI, and ultrasound techniques are useful for formulating the diagnosis based on vascularity and specific enhancement features. In this paper we will discuss the multimodal approach for diagnosis and surveillance of hepatocellular carcinoma. We will also furnish the latest staging and treatment, epidemiology, clinical presentation, pathology and laboratory findings in hepatocellular carcinoma.
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Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética , Estadificación de Neoplasias , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
Multidetector row computed tomography (CT) can acquire abdominal images of unprecedented thinness in a single breath-hold. This study investigated whether acquiring source axial images at 1.25 mm as opposed to 2.5 mm would result in a perceptible difference in image quality for coronal oblique reformations. Similarly, the hypothesis that a slice pitch of 3:1 would be superior to 6:1 was evaluated. Twenty-nine CT studies were retrospectively evaluated. The images were divided into four groups: 1.25-mm axial images, pitch 3:1; 2.5-mm axial images, pitch 3:1; 1.25-mm axial images, pitch 6:1; and 2.5-mm axial images, pitch 6:1. Three radiologists evaluated by consensus the coronal oblique reformations for overall image quality and image quality of structures in the hepatoduodenal ligament and of nodal groups. Use of 1.25-mm rather than of 2.5-mm source axial images resulted in statistically significant better scores for overall image quality and visualization of the hepatic artery, portal vein, pancreatic duct, and nodal groups. However, a pitch of 3:1 rather than of 6:1 did not result in significant differences in ratings of image quality. Use of 1.25-mm rather than of 2.5-mm source axial images improves image quality when creating coronal oblique reformations for abdominal anatomy.
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Procesamiento de Imagen Asistido por Computador/métodos , Ligamentos/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Enfermedades Pancreáticas/diagnóstico por imagen , Tomografía Computarizada Espiral , Adulto , Anciano , Anciano de 80 o más Años , Duodeno/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía Abdominal , Estudios Retrospectivos , Estadísticas no ParamétricasRESUMEN
We have examined the role of the F-plasmid TraV outer membrane lipoprotein in the assembly of F-pili. Yeast two-hybrid analysis with a traV bait repeatedly identified traK, which is predicted to encode a periplasmic protein, among positive prey plasmids. A traK bait in turn identified traV and traB, which is predicted to encode an inner membrane protein. A traB bait exclusively identified traK preys. Several additional observations support the hypothesis that TraV, TraK and TraB form a complex in Escherichia coli that spans the cell envelope from the outer membrane (TraV) through the periplasm (TraK) to the inner membrane (TraB). First, two-hybrid analyses indicated that TraV and TraB bind to different TraK segments, as required if TraK bridges a ternary complex. Secondly, all three proteins fractionated with the E. coli outer membrane in tra+ cells. In contrast, TraB fractionated with the inner membrane in traV or traK mutant cells, and TraK appeared in the osmotic shock fluid from the traV mutant. These results are consistent with a TraV-TraK-TraB complex anchored to the outer membrane via the TraV lipoprotein. Further, in traK mutant cells, TraV failed to accumulate to a detectable level, and the TraB level was significantly reduced, suggesting that TraV and TraB must interact with TraK for either protein to accumulate to its normal level. Both TraK and TraV accumulated in traB2[Am] cells; however, the TraB2 amber fragment could be detected by Western blot, and sequence analysis indicated that the fragment retained the TraK-binding domain suggested by yeast two-hybrid analysis. We propose that TraV is the outer membrane anchor for a trans-envelope, Tra protein structure required for the assembly of F-pili and possibly for other events of conjugal DNA transfer.
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Proteínas Bacterianas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Factor F/genética , Lipoproteínas/metabolismo , Nucleoproteínas/metabolismo , Proteínas Periplasmáticas , Plásmidos/genética , Proteínas Bacterianas/genética , Membrana Celular/genética , Membrana Celular/metabolismo , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Fimbrias Bacterianas/genética , Fimbrias Bacterianas/metabolismo , Lipoproteínas/genética , Nucleoproteínas/genética , Técnicas del Sistema de Dos HíbridosRESUMEN
Current commercial radiology information systems (RIS) are designed for scheduling, billing, charge collection, and report dissemination. Academic institutions have additional requirements for their missions for teaching, research and clinical care. The newest versions of commercial RIS offer greater flexibility than prior systems. We sent questionnaires to Cerner Corporation, ADAC Health Care Information Systems, IDX Systems, Per-Se' Technologies, and Siemens Health Services regarding features of their products. All of the products we surveyed offer user customizable fields. However, most products did not allow the user to expand their product's data table. The search capabilities of the products varied. All of the products supported the Health Level 7 (HL-7) interface and the use of structured query language (SQL). All of the products were offered with an SQL editor for creating customized queries and custom reports. All products included capabilities for collecting data for quality assurance and included capabilities for tracking "interesting cases," though they varied in the functionality offered. No product offered dedicated functions for research. Alternatively, radiology departments can create their own client-server Windows-based database systems to supplement the capabilities of commercial systems. Such systems can be developed with "web-enabled" database products like Microsoft Access or Apple Filemaker Pro.
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Sistemas de Computación , Sistemas de Información Radiológica , HumanosRESUMEN
There is an urgent need for robust empirical data to guide the assessment and treatment of patients near the end of life. Because they are important providers of end-of-life care in this country, hospices have an important role to play in facilitating this research. However, hospices may also face considerable ethical challenges in doing so. This task force statement begins by discussing the importance of hospices' potential contributions to research. Next, we describe ways in which characteristics of hospice patients, and hospices' structure, create ethical challenges that may limit these contributions. We conclude by proposing ways in which hospices and national professional organizations can begin to overcome some of these challenges.
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Ética Institucional , Ética Médica , Guías como Asunto , Hospitales para Enfermos Terminales/normas , Experimentación Humana , Apoyo a la Investigación como Asunto/normas , Comités de Ética en Investigación , Humanos , Cuidados Paliativos , Sociedades , Estados UnidosRESUMEN
A partial blockade of the multiple actions of cocaine is one strategy by which cocaine dependence may be treated. Risperidone, a 5-hydroxytryptamine and dopamine D2 antagonist, is an atypical antipsychotic and was a candidate medication for the treatment of cocaine dependence. One hundred ninety-three cocaine-dependent subjects were enrolled in a 12-week, randomized, double-blind, placebo-controlled trial. Subjects initially received either placebo or 4 or 8 mg of risperidone, with a subsequent change to active doses of 2 mg and 4 mg. Subjects attended the clinic twice each week, provided urine samples, obtained medication, and underwent one behavioral therapy session per week. The study was terminated at the interim analysis. Retention was worse for the 4- and 8-mg active medication groups. Side effects were primarily associated with the 8-mg dose, although neither 2 mg nor 4 mg was well accepted by subjects. There was no reduction in cocaine use associated with risperidone. The results suggest that although antagonists might be a useful treatment approach, such as in the treatment of opiate dependence, risperidone is unlikely to find broad acceptance with the treatment-seeking population.
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Trastornos Relacionados con Cocaína/tratamiento farmacológico , Antagonistas de Dopamina/uso terapéutico , Risperidona/uso terapéutico , Adulto , Cocaína/análogos & derivados , Cocaína/orina , Antagonistas de Dopamina/efectos adversos , Método Doble Ciego , Femenino , Humanos , Masculino , Pacientes Desistentes del Tratamiento , Psicoterapia , Recurrencia , Risperidona/efectos adversos , Factores de TiempoRESUMEN
This paper reports on a survey conducted among elderly Chinese in Taiwan and Americans in eastern Oregon. The focus is on health status and selected social network characteristics (such as range, density, and percentage of relatives) as they relate to life satisfaction. In addition to examining differences among these and other variables in the two national samples, two hypotheses are tested using hierarchical regression analysis. The first hypothesis relates higher values of range and density to greater life satisfaction. The second is a test of the stress-buffering hypothesis. We then examine the data controlling for gender and conclude with a discussion and interpretation of both the national and gender differences yielded by this analysis.
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The work of the clinician and that of the researcher are presented as representing 2 cultures that cannot exist without each other. A third culture is described to reflect the common human experience of death and grief that invariably informs the work of both clinicians and researchers. At different times in our lives we can be both the subjects and the objects of the work in which we are involved. The author's experience as co-principal investigator with the Massachusetts General Hospital/Harvard Child Bereavement Study and the application of qualitative research is used to exemplify these ideas and demonstrate how the cultures can be integrated.
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Cultura , Investigación , Tanatología , Aflicción , Humanos , Acontecimientos que Cambian la VidaRESUMEN
Elaboration of conjugative (F) pili by F+ strains of Escherichia coli requires the activities of over a dozen F-encoded DNA transfer (Tra) proteins. The organization and functions of these proteins are largely unknown. Using the yeast two-hybrid assay, we have begun to analyse binary interactions among the Tra proteins required for F-pilus formation. We focus here on interactions involving F-pilin, the only known F-pilus subunit. Using a library of F tra DNA fragments that contained all the F genes required for F pilus formation in a yeast GAL4 activation domain vector (pACTII), we transformed yeast containing a plasmid (pAS1CYH2traA) encoding a GAL4 DNA-binding domain-F-pilin fusion. Doubly transformed cells were screened for GAL4-dependent gene expression. This screen repeatedly identified only a single Tra protein, TraQ, previously identified as a likely F-pilin chaperone. The F-pilin-TraQ interaction appeared to be specific, as no transcriptional activation was detected in yeast transformants containing pACTIItraQ plasmids and the Salmonella typhi pED208 traA gene cloned in pAS1CYH2. Two traQ segments isolated in the screen against F-pilin were tested for complementation of a traQ null allele in E. coli. One, lacking the first 11 (of 94) TraQ amino acids, restored DNA donor activity, donor-specific bacteriophage sensitivity and membrane F-pilin accumulation to wild-type levels. The second, lacking the first 21 amino acids, was much less effective in these assays. Both TraQ polypeptides accumulated in E. coli as transmembrane proteins. The longer, biologically active segment was fused to the GAL4 DNA-binding domain gene of pAS1CYH2 and used to screen the tra fragment library. The only positives from this screen identified traA segments. The fusion sites between the traA and GAL4 segments identified the hydrophobic, C-terminal domain IV of F-pilin as sufficient for the interaction. As TraQ is the only Tra protein required for the accumulation of inner membrane F-pilin, the interaction probably reflects a specific, chaperone-like function for TraQ in E. coli. Attempts to isolate an F-pilin-TraQ complex from E. coli were unsuccessful, suggesting that the interaction between the two is normally transient, as expected from previous studies of the kinetics of TraA membrane insertion and processing to F-pilin.
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Proteínas Bacterianas/metabolismo , Proteínas de Escherichia coli , Factor F/genética , Proteínas de la Membrana/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Fimbrias , Eliminación de Gen , Biblioteca de Genes , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Técnicas del Sistema de Dos HíbridosAsunto(s)
Fibrinolíticos/uso terapéutico , Derrame Pleural Maligno/tratamiento farmacológico , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Tubos Torácicos , Drenaje , Esquema de Medicación , Femenino , Fibrinolíticos/administración & dosificación , Humanos , Instilación de Medicamentos , Masculino , Persona de Mediana Edad , Derrame Pleural Maligno/terapia , Pleurodesia , Estudios Prospectivos , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificaciónRESUMEN
OBJECTIVE: Tuberculosis in the abdominal lymph nodes may be difficult to distinguish from lymphomas. This study evaluated specific CT imaging criteria for differentiating these entities. MATERIALS AND METHODS: We retrospectively reviewed the anatomic distribution and CT enhancement patterns of disease in 69 patients, 26 (38%) with tuberculosis and 43 (62%) with untreated lymphomas involving abdominal lymph nodes. Of the patients with tuberculosis, five (19%) had disseminated disease and 21 (81%) had nondisseminated disease. Of the patients with lymphomas, 16 (37%) had Hodgkin's disease and 27 (63%) had non-Hodgkin's lymphoma. RESULTS: Disseminated and nondisseminated tuberculosis involved predominantly lesser omental, mesenteric, anterior pararenal, and upper paraaortic lymph nodes. Lower paraaortic lymph nodes were involved more often in Hodgkin's disease (15 patients [94%]), non-Hodgkin's lymphoma (24 patients [89%]), and disseminated tuberculosis (five patients [100%]) than in nondisseminated tuberculosis (one patient [5%]). Mesenteric lymph nodes were involved more often in disseminated tuberculosis (four patients [80%]) and nondisseminated tuberculosis (11 patients [52%]) than in Hodgkin's disease (one patient [6%]) (p < .01). Anatomic distribution was not different between disseminated tuberculosis and non-Hodgkin's lymphoma. Tuberculous lymphadenopathy commonly showed peripheral enhancement, frequently with a multilocular appearance, whereas lymphomatous adenopathy characteristically showed homogeneous attenuation (14 patients [87.5%] with Hodgkin's disease and 19 patients [70%] with non-Hodgkin's lymphoma [p < .01]). CONCLUSION: Our findings indicate that the anatomic distribution and specific enhancement patterns of lymphadenopathy seen on contrast-enhanced CT can be useful in differentiating between tuberculosis and untreated lymphomas of the abdominal lymph nodes.
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Enfermedad de Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Tuberculosis Ganglionar/diagnóstico por imagen , Abdomen , Adulto , Medios de Contraste , Diagnóstico Diferencial , Diatrizoato de Meglumina , Femenino , Humanos , Masculino , Estudios RetrospectivosRESUMEN
Lever pressing maintained by intraperitoneal (i.p.) injections of etonitazene was established in five Long Evans hooded rats. Each training session consisted of an 8-min fixed interval (FI) during which lever pressing was maintained by food pellets delivered at the end of the interval. Food delivery was accompanied by illumination of stimulus lights in the chamber. Every 20th response during the 8 min interval also produced a brief illumination of the stimulus lights (FI 8 min (FR 20:S)). Administration of etonitazene was then introduced. Immediately following food delivery, the rat received an i.p. drug injection and was returned to the operant chamber for 30 min. During this confinement, the stimulus lights remained illuminated. This procedure resembles conditioned place preference in that an environment is paired with the effects of an investigator-delivered drug. When food pellet delivery subsequently was discontinued, responding persisted when followed by drug, but not saline, administration. Alternating blocks of sessions with administration of etonitazene (6.0-9.0 microg/kg) or saline produced corresponding increases or decreases in responding. These results indicate that etonitazene can function as a reinforcer when administered to rats by the i.p. route, and thus extend the range of conditions under which drug reinforcement can be investigated.
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Bencimidazoles/administración & dosificación , Narcóticos/administración & dosificación , Animales , Inyecciones Intraperitoneales , Masculino , Ratas , Ratas Long-Evans , Refuerzo en Psicología , AutoadministraciónRESUMEN
Constructing a connection to the deceased is helpful to children in adjusting to the death of a parent. Using interview data from a subset of a larger study of childhood bereavement, this paper describes ways in which parents help children, ages 10-12, build this connection, provides case examples contrasting parental attitudes and behavior that are helpful and those that are not helpful to the child, and offers implications for clinical practice.
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Aflicción , Salud de la Familia , Relaciones Padres-Hijo , Responsabilidad Parental/psicología , Psicología Infantil , Adaptación Psicológica , Niño , Mecanismos de Defensa , Femenino , Humanos , Imaginación , Masculino , Privación Materna , Memoria , Apego a Objetos , Privación PaternaRESUMEN
OBJECTIVE: Our objective was to determine the level and timing of peak hepatic enhancement in children using power injection of contrast media, helical CT, and computer-automated scan technology. SUBJECTS AND METHODS: Forty-nine abdominal CT studies were performed using computer-automated scan technology. Patients were divided into four groups on the basis of body weight and contrast dose (group 1A, < or = 20 kg and 2 ml/kg; group 1B, < or = 20 kg and 3 ml/kg; group 2, 21-40 kg and 2 ml/kg; group 3, > 40 kg and < or = 2 ml/kg). Contrast injection rates were based on body weight (groups 1A and 1B, 1 ml/sec; group 2, 1.5 ml/sec; and group 3, 2 ml/sec). The peak hepatic enhancement level in Hounsfield units and the time to reach peak enhancement were determined for each patient. RESULTS: The mean peak hepatic enhancement and time to peak enhancement after completion of contrast injection were group 1A, 45 H and 11 sec; group 1B, 62 H and 3 sec; group 2, 52 H and 12 sec; and group 3, 45 H and 10 sec. CONCLUSION: The level and timing of peak hepatic enhancement in pediatric patients can be obtained using computer-automated scan technology. These data may then be used to optimize hepatic enhancement when obtaining helical abdominal CT scans of pediatric patients.
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Medios de Contraste/administración & dosificación , Hígado/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Inyecciones Intravenosas/métodos , MasculinoRESUMEN
OBJECTIVE: We conducted a survey of the members of the Society of Computed Body Tomography/Magnetic Resonance to assess current techniques in liver imaging using helical CT. MATERIALS AND METHODS: The survey, which was designed to update earlier surveys from 1987 and 1993, included a questionnaire distributed to 77 members of the Society of Computed Body Tomography/Magnetic Resonance. RESULTS: Forty-nine members responded, representing 28 institutions. In 1993, 19% (5/26) of institutions used helical scanners, compared with 82% (23/28) in 1996. The group of institutions with helical CT served as the focus of this survey. In 1993, 58% of institutions used 1-cm collimation: in 1996, 78% (18/23) used thinner, 7- to 8-mm collimation. In 1987, 41% used power injectors compared with 85% in 1993 and 100% in 1996. In 1996, monophasic injections were used by 96% (22/23) of institutions. In 1993, most institutions used a contrast material injection rate of 1.5-2.0 ml/sec; in 1996, most used a 2.5-3.0 ml/sec injection rate. In 1993, 96% of institutions used 125-150 ml of contrast material; in 1996, 57% (13/23) of institutions used 125-150 ml and 30% of institutions used less than 125 ml of contrast material. A delay time of 21-45 see was used by 83% of institutions in 1993, whereas in 1996, 83% (19/23) of institutions used a longer delay time of 50-80 sec. In 1996, 13% of institutions used an individual scan delay technology and all institutions performed multiphasic scanning of hypervascular lesions. CONCLUSION: The availability of helical CT has changed radiologists' approach to liver imaging. The greatest effects of which are a more widespread use of power injectors, longer delay times, thinner collimation, increased contrast material injection rates, decreased contrast material volumes, and multiphasic scanning.