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1.
Plant Cell ; 4(6): 657-665, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12297657

RESUMEN

We have determined that the synthesis of heat shock proteins is regulated ultimately at the translational level in heat-shocked carrot callus cells and somatic embryos. Polysome analysis revealed that heat-shocked callus cells do not translate most heat shock transcripts, which they abundantly synthesize and accumulate. By contrast, heat-shocked globular embryos accumulate low levels of heat shock mRNA but selectively translate more of the heat shock mRNA molecules compared to callus cells and embryos of later stages. The overall result of these different translational control schemes is that undifferentiated callus cells and globular embryos synthesize comparable levels of heat shock proteins even though they have large differences in heat shock transcript levels.

2.
Plant Cell ; 6(12): 1713-1729, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12244232

RESUMEN

We identified two Arabidopsis embryo mutants, designated as raspberry1 and raspberry2, by screening T-DNA-mutagenized Arabidopsis lines. Embryogenesis in these mutants is indistinguishable from that of wild-type plants until the late-globular stage, after which raspberry1 and raspberry2 embryos fail to undergo the transition to heart stage, remain globular shaped, and proliferate an enlarged suspensor region. raspberry1 and raspberry2 embryo-proper regions enlarge during embryogenesis, become highly vacuolate, and display prominent convex, or "raspberry-like" protuberances on their outer cell layers. In situ hybridization studies with several embryo cell-specific mRNA probes indicated that the raspberry1 and raspberry2 embryo-proper regions differentiate tissue layers in their correct spatial contexts and that the regulation of cell-specific genes within these layers is normal. Surprisingly, a similar spatial and temporal pattern of mRNA accumulation occurs within the enlarged suspensor region of raspberry1 and raspberry2 embryos, suggesting that a defect in embryo-proper morphogenesis can cause the suspensor to take on an embryo-proper-like state and differentiate a radial tissue-type axis. We conclude that cell differentiation can occur in the absence of both organ formation and morphogenesis during plant embryogenesis and that interactions occur between the embryo-proper and suspensor regions.

3.
Plant Cell ; 6(12): 1731-1745, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12244233

RESUMEN

LEAFY COTYLEDON1 (LEC1) is an embryo defective mutation that affects cotyledon identity in Arabidopsis. Mutant cotyledons possess trichomes that are normally a leaf trait in Arabidopsis, and the cellular organization of these organs is intermediate between that of cotyledons and leaves from wild-type plants. We present several lines of evidence that indicate that the control of late embryogenesis is compromised by the mutation. First, mutant embryos are desiccation intolerant, yet embryos can be rescued before they dry to yield homozygous recessive plants that produce defective embryos exclusively. Second, although many genes normally expressed during embryonic development are active in the mutant, at least one maturation phase-specific gene is not activated. Third, the shoot apical meristem is activated precociously in mutant embryos. Fourth, in mutant embryos, several genes characteristic of postgerminative development are expressed at levels typical of wild-type seedlings rather than embryos. We conclude that postgerminative development is initiated prematurely and that embryonic and postgerminative programs operate simultaneously in mutant embryos. The pleiotropic effects of the mutation indicate that the LEC1 gene plays a fundamental role in regulating late embryogenesis. The role of LEC1 and its relationship to other genes involved in controlling late embryonic development are discussed.

4.
Genetics ; 95(3): 673-91, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6777246

RESUMEN

The amount, by mass, of poly(A+) mRNA present in the polyribosomes of third-instar larvae of Drosophila melanogaster, and the relative contribution of the poly(A+) mRNA to the sequence complexity of total polysomal RNA, has been determined. Selective removal of poly(A+) mRNA from total polysomal RNA by use of either oligo-dT-cellulose, or poly(U)-sepharose affinity chromatography, revealed that only 0.15% of the mass of the polysomal RNA was present as poly(A+) mRNA. The present study shows that this RNA hybridized at saturation with 3.3% of the single-copy DNA in the Drosophila genome. After correction for asymmetric transcription and reactability of the DNA, 7.4% of the single-copy DNA in the Drosophila genome is represented in larval poly(A+) mRNA. This corresponds to 6.73 X 10(6) nucleotides of mRNA coding sequences, or approximately 5,384 diverse RNA sequences of average size 1,250 nucleotides. However, total polysomal RNA hybridizes at saturation to 10.9% of the single-copy DNA sequences. After correcting this value for asymmetric transcription and tracer DNA reactability, 24% of the single-copy DNA in Drosophila is represented in total polysomal RNA. This corresponds to 2.18 X 10(7) nucleotides of RNA coding sequences or 17,440 diverse RNA molecules of size 1,250 nucleotides. This value is 3.2 times greater than that boserved for poly(A+) mRNA, and indicates that congruent to 69% of the polysomal RNA sequence complexity is contributed by nonadenylated RNA. Futhermore, if the number of different structural genes represented in total polysomal RNA is congruent to 1.7 X 10(4), then the number of genes expressed in third-instar larvae exceeds the number of chromomeres in Drosophila by about a factor of three. This numbeology indicates that the number of chromomeres observed in polytene chromosomes does not reflect the number of structural gene sequences in the Drosophila genome.


Asunto(s)
Drosophila melanogaster/genética , Poli A/genética , ARN Mensajero/genética , Animales , ADN/genética , Genes , Larva/metabolismo , Hibridación de Ácido Nucleico , Poli A/metabolismo , ARN Mensajero/metabolismo , ARN Ribosómico/genética
5.
Arch Intern Med ; 158(22): 2453-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9855383

RESUMEN

BACKGROUND: Respiratory tract viral infections (RTVIs) have been identified frequently in association with asthma exacerbations in children, but few studies have shown similar rates of viral infections in adults with asthma. Further studies using newer diagnostic techniques to evaluate the frequency of RTVIs in adults with acute exacerbations of asthma need to be performed. METHODS: Twenty-nine asthmatic adults were recruited from the pulmonary clinic of an urban county hospital and were followed up in a longitudinal cohort study for signs and symptoms of asthma and RTVI. One hundred twenty-two asthmatic adults presenting to the emergency department (ED) of the same hospital with acute symptoms of asthma underwent evaluation for RTVI in a cross-sectional prevalence study. In both studies, respiratory secretions and paired serum samples were collected from subjects with acute wheezing episodes and evaluated using virus culture, serologic testing, and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In the longitudinal cohort study, 138 respiratory illnesses, of which 87 were asthma exacerbations, were evaluated; 41% of all illnesses and 44% of asthma exacerbations were associated with an RTVI. In the ED study, 148 asthma exacerbations were evaluated; 55% were associated with an RTVI. An RTVI was identified in 21 (50%) of 42 of the subjects hospitalized in the ED study. Picornaviruses (rhinoviruses), coronaviruses, and influenza viruses were the most commonly identified causes of RTVI. Forty-six (60%) of the 77 picornavirus infections and 22 (71%) of the 31 coronavirus infections were identified only using RT-PCR. CONCLUSIONS: Asthmatic exacerbations in adults are frequently associated with an RTVI. Identification of such infections often requires newer diagnostic methods, such as virus-specific RT-PCR. The high frequency of RTVIs identified in association with asthmatic exacerbations in adults from the inner city suggests that strategies for the prevention of RTVI should be targeted toward this population.


Asunto(s)
Asma/complicaciones , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/virología , Enfermedad Aguda , Adulto , Anticuerpos Antivirales/sangre , Coronaviridae/genética , Coronaviridae/inmunología , Estudios Transversales , Cartilla de ADN , ADN Viral/aislamiento & purificación , Diagnóstico Diferencial , Femenino , Humanos , Estudios Longitudinales , Masculino , Orthomyxoviridae/genética , Orthomyxoviridae/inmunología , Prevalencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rhinovirus/genética , Rhinovirus/inmunología , Texas , Salud Urbana
6.
Intensive Care Med ; 20(5): 328-34, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-7930026

RESUMEN

OBJECTIVE: To evaluate the effects of HA-1A, a human monoclonal antiendotoxin antibody, in septic patients with ARDS. DESIGN: Substudy of a multicenter, double-blinded, placebo-controlled trial of HA-1A in septic patients. PATIENTS: 63 septic patients with ARDS at the time of study entry. INTERVENTION: A single intravenous injection of HA-1A (100 mg) or placebo. RESULTS: A quantitative radiographic score, the PaO2/FIO2 ratio and an index of the severity of ARDS did not show a significant difference between the treatment and placebo groups at 3, 5 and 7 days after treatment. The duration of endotracheal intubation did not differ between the two groups. 15 of 30 HA-1A treated patients (50%) and 23 of 33 placebo-treated patients (69.7%) died within 28 days. The daily mortality was always lower in the HA-1A group, but this difference was not statistically significant at 28 days. The 28-day survival curves for the two treatment groups adjusted by covariate analysis were not significantly different (p = 0.07). Using logistic regression, a significant independent effect of HA-1A treatment was detected upon the early survival rate at 7 days (p = 0.03) but not at 14 and 28 days. CONCLUSION: A single injection of HA-1A in septic patients with ARDS did not reverse acute respiratory failure or improve long-term survival.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Endotoxinas/inmunología , Inmunoglobulina M/uso terapéutico , Síndrome de Dificultad Respiratoria/terapia , Sepsis/terapia , Adulto , Anciano , Anticuerpos Monoclonales Humanizados , Método Doble Ciego , Femenino , Humanos , Incidencia , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Síndrome de Dificultad Respiratoria/mortalidad , Factores de Riesgo , Sepsis/complicaciones , Sepsis/diagnóstico por imagen , Sepsis/mortalidad , Factores de Tiempo
7.
Crit Care Clin ; 14(4): 611-27, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9891630

RESUMEN

Vasodilators that affect the pulmonary vasculature are appealing adjuncts in many cardiopulmonary conditions that require mechanical ventilation such as ARDS, COPD, PPHN, and cardiothoracic surgery. The adverse systemic effects of parenteral PGE1 and parenteral prostacyclin limit their usefulness in critically ill patients. Liposomal PGE1 has few systemic effects, but thus far has not resulted in a significant clinical benefit in patients with ARDS. Inhaled NO and aerosolized prostacyclin offer the advantage of selective pulmonary vasodilation with minimal systemic effects. Both agents decrease PAP and in many clinical situations improve oxygenation; however, the physiologic effects of inhaled NO and aerosolized prostacyclin have not convincingly led to improved clinical outcomes. Currently, use of vasodilators in mechanically ventilated patients remains investigational.


Asunto(s)
Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/terapia , Respiración Artificial/métodos , Vasodilatadores/uso terapéutico , Administración por Inhalación , Alprostadil/uso terapéutico , Quimioterapia Adyuvante , Epoprostenol/uso terapéutico , Humanos , Infusiones Intravenosas , Óxido Nítrico/uso terapéutico , Consumo de Oxígeno/efectos de los fármacos , Presión Esfenoidal Pulmonar/efectos de los fármacos
8.
Crit Care Clin ; 15(2): 235-49, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10331126

RESUMEN

Individuals at extremes of age and those who have certain underlying medical conditions are at greatest risk for hypothermia. Hypothermia may occur during any season of the year and in any climate. Prompt recognition of hypothermia and early institution of the rewarming techniques are imperative for a successful outcome with minimal complications. Several rewarming techniques are available and the decision to use any of them depends on the degree of hypothermia, the condition of the patient, and the rewarming rate possible with the technique chosen.


Asunto(s)
Hipotermia/diagnóstico , Hipotermia/terapia , Resucitación , Recalentamiento , Electrocardiografía , Humanos , Hipotermia/fisiopatología , Pronóstico , Recalentamiento/métodos
9.
Crit Care Clin ; 12(4): 865-74, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8902375

RESUMEN

Arterial blood gas (ABG) measurements are one of the most frequently requested laboratory examinations in critically ill patients. ABGs include measurement of pHa, PaCO2, PaO2, and oxyhemoglobin saturation. These measurements allow for assessment of the nature, progression, and severity of metabolic and respiratory disturbances.


Asunto(s)
Análisis de los Gases de la Sangre/instrumentación , Análisis de los Gases de la Sangre/métodos , Análisis de los Gases de la Sangre/normas , Análisis de los Gases de la Sangre/tendencias , Electroquímica , Diseño de Equipo , Tecnología de Fibra Óptica , Colorantes Fluorescentes , Humanos , Espectrofotometría
10.
Clin Cardiol ; 15(4): 253-8, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1563128

RESUMEN

The pathogenesis of acute myocardial ischemia or infarction following cocaine abuse is not known. Cocaine causes an increase in circulating catecholamines. Therefore alpha-adrenergic mediated focal or generalized coronary artery spasm has been presumed to be the likely mechanism to induce ischemia. However, coronary vasospasm in chronic cocaine abusers has not been demonstrated angiographically. Moreover, it has been observed that patients commonly manifest ischemic changes hours up to a week after abusing cocaine. In order to evaluate direct effects of cocaine on coronary vasculature, 6 chronic cocaine abusers admitted with prolonged chest pain and electrocardiographic ST- and T-wave changes were studied. Cocaine administered intravenously (maximum 32 mg) produced subjective sensation of central nervous stimulation (the "high") in all patients. However there was no significant change in coronary artery diameter (assessed by computer-assisted quantitative technique), myocardial perfusion (assessed by contrast echocardiography) or left ventricular wall motion (assessed by two-dimensional echocardiography) as compared with the baseline values. Coronary sinus flow (thermodilution) showed an upward trend, a probable reflection of a significant increase in cardiac output (average 62%, p less than 0.007). Despite a significant elevation in heart rate (average 56%, p less than 0.007), mean systemic arterial pressure (average 12%, p less than 0.05) and rate-pressure product (average 69%, p less than 0.005), no symptomatic or acute electrocardiographic changes were observed. It is concluded that recreational doses of cocaine do not cause focal or generalized coronary vasospasm or reduced myocardial perfusion in patients who present with chest pain temporally related to cocaine.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cocaína/toxicidad , Circulación Coronaria/efectos de los fármacos , Vasoespasmo Coronario/inducido químicamente , Hemodinámica/efectos de los fármacos , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Catecolaminas/metabolismo , Dolor en el Pecho/inducido químicamente , Angiografía Coronaria , Vasoespasmo Coronario/diagnóstico por imagen , Vasoespasmo Coronario/fisiopatología , Vasos Coronarios/efectos de los fármacos , Electrocardiografía , Femenino , Humanos , Masculino
11.
Dent Clin North Am ; 30(4): 739-43, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3536626

RESUMEN

Traditionally, each professional school has developed its own course or department of health care informatics. We may find it more efficient and productive to establish a department of Medical Informatics to serve all health science colleges. Therefore the initial costs would be reduced and the common knowledge bank would be greatly increased. In a position paper written for the Association of Academic Health Centers lies the detailed plans for the establishment of an integrated health sciences center computer resource. The inclusion of computer courses in the curriculum can be summarized in the following action step. The chief administrative officer of the academic health center should facilitate the work of the deans of the schools of the health professions in convening faculty task forces that will address the introduction of computer literacy and computer applications in health care to the curricula. Although dental informatics is still in its infancy, we must lay a solid foundation for the controlled growth and development of this field of dental science. The problems encountered in developing a course in dental informatics are not unique to this one area. All specialties of health care are grappling with the questions posed by medical informaticians. Although each specialty has its own needs and requirements, the basic underlying principles of medical informatics remains the same. The knowledge we can gain by the exchange of experiences between all fields can greatly increase the speed and accuracy of development. The primary goal of computer literacy in dental education should be to prepare our students for the changing practice environment of the future.


Asunto(s)
Computadores , Odontología , Alfabetización Digital , Instrucción por Computador , Curriculum , Diagnóstico por Computador , Educación en Odontología , Administración de la Práctica Odontológica
12.
Dent Clin North Am ; 30(4): 731-8, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3465631

RESUMEN

The results of this study indicated that some new patterns are emerging in computer usage by dentists. The majority in this study reported utilizing micro- and minicomputers rather than commercial services. The increasing acceptance of personal computers and their decreasing costs will certainly contribute to increased utilization and the development of additional applications.


Asunto(s)
Computadores , Administración de la Práctica Odontológica , California , Microcomputadores , Minicomputadores , Pennsylvania , Administración de la Práctica Odontológica/economía
13.
J Marital Fam Ther ; 19(4): 403-13, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21118478

RESUMEN

Using ideas from postmodern thought, a process of therapy is described in which couples are "separated" from the reciprocal patterns which have become restraining and are currently affecting the relationship. The description of the pattern is co-created between the therapist and the couple. Once a different pattern begins to emerge, various aspects of relationship or gender discourse and their effect on the relationship are worked with as needed. To help couples break these patterns and separate from the influence of discourse which they determine to be not suitable to their own preferred descriptions, the therapist brings forth other descriptions of the people and/or the relationship which are grounded in their experience. Therapy becomes a parallel process of deconstructing patterns/discourse and restorying along preferred lines.

14.
J Am Vet Med Assoc ; 174(6): 604-9, 1979 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-422464

RESUMEN

Toxoplasmosis was diagnosed at necropsy in a 4-week-old pig from a litter of 16 born to a clinically normal sow. Multifocal acute necrosis of blood vessels and parenchyma was found in the small intestine, mesenteric lymph nodes, liver, lungs, and brain. Numerous tachyzoites, ultrastructurally indistinguishable from Toxoplasma gondii, were found in lesions. The affected pig and seven other littermates died after diarrhea had developed within 1 to 2 weeks of birth. The most likely source of infection was oocysts from cats on the farm.


Asunto(s)
Enfermedades de los Porcinos/patología , Toxoplasmosis Animal/patología , Animales , Encéfalo/patología , Diagnóstico Diferencial , Indiana , Intestino Delgado/patología , Riñón/patología , Hígado/patología , Pulmón/patología , Ganglios Linfáticos/patología , Bazo/patología , Porcinos , Enfermedades de los Porcinos/parasitología , Toxoplasmosis Animal/parasitología
15.
Adv Dent Res ; 17: 25-8, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15126202

RESUMEN

Is biomedical informatics a science or a profession? This question has been asked of many members in the biomedical informatics community, yet we still lack a response that galvanizes our community. We debate the issues over lunch. We create long, multi-threaded e-mail discussions, we write papers on the topic, and still we aren't able to convince ourselves-let alone the rest of the scientific community. In this paper, I will describe a curriculum model for biomedical informatics and research that is developing at Columbia University, Department of Biomedical Informatics (DBMI). We believe that a strong educational foundation creates competent professionals who, in turn, comprise a bioinformatics culture. The outcome of DBMI's curriculum design and competency project will be a set of biomedical informatics competencies which we believe will define the core knowledge and skills of the field.


Asunto(s)
Biología Computacional/educación , Informática Médica/educación , Curriculum , Humanos , Modelos Educacionales , Ocupaciones , Competencia Profesional , Sociedades Médicas
16.
J Dent Educ ; 60(1): 33-40, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8594101

RESUMEN

Computer networking is a fundamental change in communication technology that carries with it the same significance as the development of human language. The discovery of new tools adds to the human experience, but the ability to communicate and share that knowledge and wisdom results in a factorial increase in the collective wisdom of a global community. This paper presents a brief history and overview of the Internet and then discusses how network application tools can be used in dentistry. Examples of various implementations will be given and a brief discussion of some constraints to implementation of network technology is also included.


Asunto(s)
Redes de Comunicación de Computadores , Administración de la Práctica Odontológica , Humanos , Sistemas de Información
17.
N Y State Dent J ; 61(8): 64-9, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7478385

RESUMEN

The discovery of new tools adds to the human experience, but our newfound ability to communicate and share knowledge and wisdom almost instantaneously results in a factorial increase in the collective wisdom of a global community. Computer networks continue to expand and reach into every corner of the globe. This global information network has the potential to affect many aspects of society. This paper presents a brief history and overview of the Internet and network application tools and discusses some of the ethical issues that need to be addressed as the Internet grows to touch every part of our lives.


Asunto(s)
Redes de Comunicación de Computadores , Sistemas de Información , Telemedicina , Confidencialidad , Odontología , Humanos , Administración de la Práctica Odontológica
18.
Plant Cell ; 5(10): 1411-1423, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12271037
19.
Intensive care med ; 43(3)Mar. 2017.
Artículo en Inglés | BIGG | ID: biblio-948600

RESUMEN

OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy wasdeveloped at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroupsand among the entire committee served as an integral part of the development. METHODS: The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. CONCLUSIONS: Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.(AU)


Asunto(s)
Humanos , Choque Séptico/tratamiento farmacológico , Sepsis/tratamiento farmacológico , Planificación de Atención al Paciente , Respiración Artificial , Vasoconstrictores/uso terapéutico , Calcitonina/uso terapéutico , Evaluación Nutricional , Enfermedad Crónica/tratamiento farmacológico , Terapia de Reemplazo Renal , Fluidoterapia/métodos , Antibacterianos/administración & dosificación
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