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1.
Mol Psychiatry ; 23(4): 973-984, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28397838

RESUMEN

Approximately 1% of the global population is affected by intellectual disability (ID), and the majority receive no molecular diagnosis. Previous studies have indicated high levels of genetic heterogeneity, with estimates of more than 2500 autosomal ID genes, the majority of which are autosomal recessive (AR). Here, we combined microarray genotyping, homozygosity-by-descent (HBD) mapping, copy number variation (CNV) analysis, and whole exome sequencing (WES) to identify disease genes/mutations in 192 multiplex Pakistani and Iranian consanguineous families with non-syndromic ID. We identified definite or candidate mutations (or CNVs) in 51% of families in 72 different genes, including 26 not previously reported for ARID. The new ARID genes include nine with loss-of-function mutations (ABI2, MAPK8, MPDZ, PIDD1, SLAIN1, TBC1D23, TRAPPC6B, UBA7 and USP44), and missense mutations include the first reports of variants in BDNF or TET1 associated with ID. The genes identified also showed overlap with de novo gene sets for other neuropsychiatric disorders. Transcriptional studies showed prominent expression in the prenatal brain. The high yield of AR mutations for ID indicated that this approach has excellent clinical potential and should inform clinical diagnostics, including clinical whole exome and genome sequencing, for populations in which consanguinity is common. As with other AR disorders, the relevance will also apply to outbred populations.


Asunto(s)
Consanguinidad , Discapacidad Intelectual/genética , Adulto , Mapeo Cromosómico/métodos , Variaciones en el Número de Copia de ADN , Familia , Femenino , Genes Recesivos , Heterogeneidad Genética , Homocigoto , Humanos , Discapacidad Intelectual/metabolismo , Irán , Mutación con Pérdida de Función , Masculino , Análisis por Micromatrices/métodos , Persona de Mediana Edad , Mutación , Pakistán , Linaje , Secuenciación del Exoma/métodos
2.
Cancer Res ; 60(11): 2898-905, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10850435

RESUMEN

The assessment of angiogenesis in breast cancer is of importance as a key indicator of survival and response to therapy. Circulating vascular endothelial growth factor (VEGF) measurements may provide a less subjective analysis than microvessel density (MVD) or immunohistochemical analysis of VEGF expression; however, most studies have used serum, which is now known to largely reflect platelet-derived VEGF concentrations. This study examined for the first time both plasma (VEGFp) and serum (VEGFs) VEGF concentrations in 201 blood samples from pre- and postmenopausal healthy controls and from patients with benign breast disease, localized breast cancer, breast cancer in remission, or metastatic breast cancer and related these to other clinicopathological markers. VEGFp but not VEGFs concentrations of patients with localized disease were significantly elevated compared with normal controls (P = 0.016). Patients with metastatic disease had higher VEGFp and VEGFs levels than normal controls (P < 0.001, P = 0.044 respectively), and higher VEGFp, but not VEGFs, than patients with benign disease (P = 0.009) and patients with localized disease (P = 0.004). However, the highest VEGFp and VEGFs concentrations were seen in patients in remission compared with normal controls (P < 0.001 and P = 0.008, respectively). VEGFp concentrations in patients in remission were also higher than in patients with benign disease (P = 0.01) or patients with localized disease (P = 0.005). Tamoxifen treatment was significantly associated with higher circulating and platelet-derived VEGF levels. Circulating VEGF did not correlate with any clinicopathological factor, including MVD or VEGF expression. VEGF expression was significantly correlated with estrogen receptor status and inversely correlated with tumor grade. MVD correlated with tumor size. Tamoxifen-induced increases in VEGF may be important in clinical prognosis or associated pathologies.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/sangre , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/metabolismo , Factores de Crecimiento Endotelial/biosíntesis , Linfocinas/biosíntesis , Microcirculación/metabolismo , Tamoxifeno/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Plaquetas/metabolismo , Progresión de la Enfermedad , Factores de Crecimiento Endotelial/sangre , Femenino , Humanos , Inmunohistoquímica , Linfocinas/sangre , Persona de Mediana Edad , Metástasis de la Neoplasia , Inducción de Remisión , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
3.
Eur J Cancer ; 32A(4): 576-88, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8695256

RESUMEN

How do the new endocrine therapies stand up to the aims of modern endocrine therapy outlined in Table 1? We wish to see increased efficacy, decreased toxicity and improved general health in women taking a new agent. None of the new non-steroidal anti-oestrogens have shown unequivocal evidence of improved efficacy in the clinic to mirror their improved profiles over tamoxifen in preclinical studies. We know that toremifene is equivalent to tamoxifen, but we do not have any phase III data from the other four compounds in development. The specific steroidal antioestrogen, ICI 182,780, looks very promising, but is early in its developmental programme. The new aromatase inhibitors are likely to prove equal to tamoxifen or progestagens, but it is disappointing that improved oestrogen suppression has not led, to date, to improved efficacy. No comment can be made about adjuvant or preventative therapy for any of the new agents, although trials are planned for the new aromatase inhibitors in this clinical situation. Currently, the antiprogestins are disappointing and we will need to wait a considerable time for new agents in preclinical testing to reach the clinic. Many of the new agents are associated with decreased toxicity. It is likely that the NSAEs will be equitoxic with tamoxifen. The steroidal antioestrogen looks particularly non-toxic as do the new aromatase inhibitors, and thus we have an advance in terms of reduced toxicity. The effects of the new agents on the uterus, lipids and bone are in the early stages of testing. Raloxifene, ICI 182,780 and the new aromatase inhibitors are expected to have no proliferative effects on the endometrium, but only the new NSAEs are expected to have beneficial cardiovascular and skeletal effects. If the steroidal anti-oestrogens and new aromatase inhibitors become adjuvant therapies of choice, other agents to prevent osteoporosis and cardiovascular events may also have to be administered.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Animales , Antineoplásicos Hormonales/farmacología , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Antagonistas de Estrógenos/farmacología , Antagonistas de Estrógenos/uso terapéutico , Femenino , Humanos , Ratones , Ratas
4.
J Neurosurg ; 91(4): 706-9, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10507397

RESUMEN

There is increasing recognition that magnetic resonance (MR) imaging and spectroscopy may provide important information in the assessment of patients with acute brain injury. However, optimum care of the acutely head injured patient requires monitoring of intracranial pressure (ICP). Although many monitoring modalities have been integrated into commercially available MR-compatible systems, there have been no reports of commonly used intraparenchymal ICP sensors in an MR environment. The authors describe the use of an ICP micromanometer probe in an MR environment, with a fiberoptic connection that interfaces the probe with a commercially available MR-compatible monitoring system. Phantom studies were performed to demonstrate the safety and compatibility of the modified MR system at 0.5 tesla. The safety of the device was assessed in relation to its interaction with the static, gradient, and radiofrequency fields used in MR imaging. The MR compatibility was documented by demonstrating that its performance was unaffected by the operation of imaging sequences and by showing that there was no degradation of the diagnostic quality of imaging data obtained during ICP monitoring.


Asunto(s)
Presión Intracraneal , Imagen por Resonancia Magnética , Diseño de Equipo , Tecnología de Fibra Óptica , Humanos , Manometría/instrumentación , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Seguridad
5.
Blood Coagul Fibrinolysis ; 11 Suppl 1: S117-20, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10850576

RESUMEN

Rebleeding following aneurysmal subarachnoid haemorrhage is a major factor contributing to unfavourable outcome. Antifibrinolytic agents reduce the rate of rebleeding but increase the risk of cerebral ischaemia and infarction and hence provide no overall benefit. To address the theoretical concern that recombinant activated factor VII (NovoSeven, Novo Nordisk A/S, Bagsvaerd, Denmark) might increase the risk of cerebral ischaemia while stabilizing the clot at the site of aneurysmal rupture, an open-label, dose-escalation safety study has been developed in collaboration with the UK Spontaneous Intracranial Haemorrhage Group. The trial design includes the recruitment of 15 patients (aged 18 years or over) in good grade with subarachnoid haemorrhage verified by computerized tomography scan or lumbar puncture. Safety evaluation includes clinical observation, monitoring of laboratory variables, positron emission tomography (PET) scanning (rCBF, rOEF, rCMRO2) and transcranial Doppler ultrasound. To date, ten patients have been recruited [NovoSeven 80 microg/kg single bolus (n = 2), NovoSeven 80 microg/kg single bolus followed by continuous infusion at 3.5 microg/kg per h (n = 2) or 7 microg/kg per h (n = 1), or control (n = 5)]. Clinical observation, transcranial Doppler ultrasound and PET studies revealed no evidence of cerebral ischaemia in the first nine patients treated with NovoSeven. The last patient developed middle cerebral artery branch thrombosis contralateral to the aneurysm. The study is currently suspended pending further investigation.


Asunto(s)
Factor VIIa/administración & dosificación , Aneurisma Intracraneal/complicaciones , Hemorragia Subaracnoidea/tratamiento farmacológico , Adulto , Aneurisma Roto , Humanos , Proteínas Recombinantes/administración & dosificación , Prevención Secundaria , Resultado del Tratamiento
6.
Mutat Res ; 90(3): 233-45, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7035938

RESUMEN

Chemical fractions from 4 shale oils including one produced in an above-ground retort (Paraho), 2 produced below ground by in situ method (Occidental and Geokinetics), and 1 produced by a simulated modified in situ process (Livermore), were tested for mutagenicity against Salmonella typhimurium TA98 in the Ames assay system. Their mutagenic activities were compared with 2 other complex materials: a high-boiling coal distillate (The Solvent Refined Coal Process I (SRC II) heavy distillate), and a crude petroleum (Prudhoe Bay). Each material was fractionated by Sephadex LH-20 partition chromatography and by acid-base solvent extraction to provide chemical fractions for bioassay. Mutagenic activity was detected in the coal liquid (and their fractions), but not in the natural crude oil nor in any of its fractions. The basic and tar fractions derived by solvent extraction, and the LH-20 methanol fractions contained most of the mutagenic activity recovered from the unfractionated material. The heavy distillate was approx. 10 times more active in the Ames assay than the most mutagenically active shale oil. The most mutagenically active of the shale oils was about 10 times more active than the least active shale oil.


Asunto(s)
Combustibles Fósiles , Mutágenos , Pruebas de Mutagenicidad , Salmonella typhimurium/genética
7.
Plast Reconstr Surg ; 92(4): 746-9, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8356136

RESUMEN

A child with respiratory insufficiency due to a lethal syndrome known as spondylocostal dysostosis is described. Severe chest-wall deformities with resultant paradoxical chest-wall motion were successfully corrected by surgical reconstruction of the right thorax. We conclude that patients with the severe lethal form of the syndrome may benefit from aggressive surgical correction of the thoracic abnormality.


Asunto(s)
Anomalías Múltiples/cirugía , Costillas/anomalías , Columna Vertebral/anomalías , Femenino , Humanos , Recién Nacido , Complicaciones Posoperatorias/cirugía , Reoperación , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/cirugía , Costillas/cirugía , Escoliosis/etiología , Escoliosis/cirugía , Columna Vertebral/cirugía , Mallas Quirúrgicas
8.
J S Afr Vet Assoc ; 67(4): 182-7, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9284029

RESUMEN

Substantial evidence has recently accumulated showing domestic cats to be the principal reservoirs of Bartonella henselae, the aetiological agent of human diseases including cat-scratch disease, bacillary angiomatosis, bacillary peliosis and a febrile bacteraemia syndrome. To determine the prevalence of antibodies reactive with Bartonella henselae in cats from southern Africa, indirect fluorescent antibody assays were carried out on feline sera from South Africa and Zimbabwe. Overall, 23% (39/171) of cats had antibody titres > or = 1/64, with cats from Zimbabwe (24%; 28/119) having higher seroprevalences than those from South Africa (21%; 11/52) although this difference was not statistically significant. The implications of these findings for veterinarians in southern Africa are discussed.


Asunto(s)
Infecciones por Bartonella/epidemiología , Bartonella henselae/aislamiento & purificación , Enfermedades de los Gatos/epidemiología , Adolescente , África Austral/epidemiología , Animales , Animales Domésticos , Anticuerpos Antibacterianos/sangre , Infecciones por Bartonella/diagnóstico , Infecciones por Bartonella/prevención & control , Infecciones por Bartonella/veterinaria , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/prevención & control , Gatos , Niño , Reservorios de Enfermedades , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Prevalencia , Veterinarios , Zoonosis/etiología
9.
Rev. chil. dermatol ; 30(2): 138-150, 2014. ilus
Artículo en Español | LILACS | ID: biblio-835935

RESUMEN

Los hemangiomas de la infancia (HI) son los tumores de partes blandas más frecuentes de la infancia. Se presentan en un 5 por ciento- 10 por ciento de la población pediátrica. El comportamiento de estos tumores es especial, ya que, a diferencia de otras neoplasias benignas, los HI tienden a regresar e involucionar espontáneamente en un 90 por ciento. Algunos pacientes con HI pueden sufrir complicaciones tales como ulceración y hemorragia. Estas complicaciones han llevado a la búsqueda de alternativas terapéuticas, donde, por mucho tiempo fueron los esteroides la primera opción de tratamiento. Esto hasta el año 2008, cuando se descubre accidentalmente el propranolol administrado por vía oral, como alternativa terapéutica para los HI severos, convirtiéndose hasta el día de hoy, en el gold standard de tratamiento. Dado la diversidad en su presentación, y las diferentes alternativas de manejo existentes, es que esta revisión pretende abordar la patogenia, clínica y enfrentamiento de estos tumores de la infancia.


Hemangiomas of infancy (HI) are the most common soft tissue tumors of childhood. They occur in up to percent-10 percent of the pediatric population and they have a special behaviour because, unlike other benign neoplasms, HI tend to regress spontaneously in up to 90 percent of the cases. Complications such as ulceration and hemorrhage can occur. These complications have led to search for new therapeutic options. Steroids were the first choice of treatment for a long time, until 2008, when oral propranolol was accidentally discovered as a potential treatment for large HI4. Today, propranolol is the gold standard for treatment. Given their variable clinical presentation and different therapeutic options available nowadays, this paper to review the pathogenesis, clinical presentation and approach of these tumors of infancy.


Asunto(s)
Humanos , Niño , Hemangioma/diagnóstico , Hemangioma/terapia , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/terapia , Diagnóstico Diferencial , Hemangioma/clasificación , Hemangioma/complicaciones , Hemangioma/etiología , Neoplasias de los Tejidos Blandos/clasificación , Neoplasias de los Tejidos Blandos/complicaciones , Neoplasias de los Tejidos Blandos/etiología
10.
Int J Rad Appl Instrum A ; 39(12): 1197-201, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2851001

RESUMEN

The production and radiochemical separation of 52Fe from 4He irradiation of enriched 50Cr target is described. Methods developed for the recovery of the target material (50Cr) are also described. The yield of 52Fe at 38 MeV incident 4He energy is 1667 +/- 133 MBq/C (163 +/- 13 microCi/microAh) at end of bombardment and the contamination of 55Fe is only 0.008%.


Asunto(s)
Radioisótopos de Hierro , Isótopos de Cromo , Electrólisis , Helio , Oxidación-Reducción , Aceleradores de Partículas , Control de Calidad , Radioquímica
11.
Int J Rad Appl Instrum A ; 38(7): 499-501, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3040634

RESUMEN

The excitation functions for the production of 66Ga and some other radionuclides produced by the 4He-particle bombardment of a natural copper target have been measured up to 31 MeV incident energy. The radiochemical separation of 66Ga from the irradiated copper target as well as from the other radionuclides formed is described. The yield of 66Ga at 18 MeV incident energy is 708 microCi/microAh at end of bombardment and the contamination of 67Ga is 0.25%. The intended use of the 66Ga produced is to label monoclonal antibodies for PET scanning.


Asunto(s)
Radioisótopos de Galio , Radioquímica/métodos
12.
Ann Plast Surg ; 39(2): 186-9, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9262774

RESUMEN

A main concern in the use of scalp tissue expansion in the pediatric population has been the risk of skull deformation. Little is known about the long-term effects of tissue expansion on the skull and the ability of the skull to remodel following removal of the tissue expander. We report a recent case in which a 5-year-old boy had a fully inflated tissue expander retained under the scalp for a 15-month period. At surgery for removal of the implant the patient was noted to have a profound skull deformity characterized by severe calvarial depression and ridging. The patient underwent scalp reconstruction. Follow-up at 6 months revealed nearly complete remodeling of the skull with minimal visual deformity. This case demonstrates not only the profound bony deformity that can result from tissue expansion, but also the striking ability of the pediatric skull to remodel.


Asunto(s)
Remodelación Ósea/fisiología , Quemaduras/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Cuero Cabelludo/lesiones , Cráneo/lesiones , Dispositivos de Expansión Tisular , Quemaduras/diagnóstico por imagen , Preescolar , Estudios de Seguimiento , Humanos , Masculino , Radiografía , Cuero Cabelludo/cirugía , Cráneo/diagnóstico por imagen
13.
Opt Lett ; 14(1): 15-7, 1989 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19749808

RESUMEN

Two-photon-resonant, three-photon ionization of atomic hydrogen and deuterium is performed at 243 nm, and the ions are detected by time-of-flight mass spectrometry. The power dependence of the 1S-2S two-photon excitation and one-photon ionization of 2S hydrogen and deuterium are determined. The ionization step saturates at 4 x 10(6) W/cm(2). The two-photon step-power dependence varies with laser linewidth, with saturation occurring between 1 x 10(7) and 3 x 10(7) W/cm(2). The extraction electric field in the mass spectrometer does not affect the 2S excitation. Strong signals are recorded at atomic concentrations of 10(5) atoms/cm(3). Nonresonant ionization of background gases producing H(+) and D(+) is minimized.

14.
Appl Opt ; 36(15): 3187, 1997 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-18253324

RESUMEN

This issue of Applied Optics features papers on the application of laser technology to chemical and environmental analysis. Many of the contributions to this issue, although not all, result from papers presented at the 1996 OSA Topical Meeting on Laser Applications to Chemical and Environmental Analysis, which was held in Orlando, Florida, in March 1996. This successful meeting, with nearly 100 participants, continued the tradition of earlier Laser Applications to Chemical Analysis (LACA) meetings. The title change reflects an expended scope and an even greater emphasis on environmental analysis than the previous four LACA meetings.

15.
Lung ; 168(6): 297-308, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2126319

RESUMEN

The pathogenesis of pneumonitis associated with meconium aspiration is poorly understood. To explore the possibility of pulmonary cytotoxicity in association with bile salt exposure and calcium accumulation, we compared cell viability, radiolabeled calcium accumulation, and intracellular [calcium] in the presence and absence of bile salts, chenodeoxycholate, and 3 beta-OH-5-cholenoate. We assessed viability of type II pneumocytes in culture by cell permeability to trypan blue dye, incorporation of leucine into cellular proteins, and cellular morphology. Intracellular calcium concentrations were monitored with fluorescent dye methodology. At micromolar concentrations, the above bile salts increased cell permeability by as much as 9-fold and decreased leucine incorporation by as much as 5-fold. Radiolabeled calcium accumulation increased by as much as 2.5-fold and intracellular [calcium] transiently increased by as much as 6-fold. Studies using bile salts extracted from meconium yielded similar results. Correlation of calcium accumulation to viability studies yielded a direct relationship with cell permeability and an inverse relationship with leucine incorporation. We speculate that bile salt-induced accumulation of intracellular calcium in lung cells may contribute to the pathogenesis of meconium aspiration pneumonitis.


Asunto(s)
Ácidos y Sales Biliares/farmacología , Calcio/metabolismo , Pulmón/metabolismo , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Supervivencia Celular , Ácido Quenodesoxicólico/farmacología , Ácidos Cólicos/farmacología , Humanos , Recién Nacido , Pulmón/citología , Masculino , Síndrome de Aspiración de Meconio/etiología , Ratas , Ratas Endogámicas
16.
Int J Rad Appl Instrum A ; 37(2): 105-9, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2428771

RESUMEN

The production and radiochemical separation of 55Co from deuteron irradiation of enriched 54Fe target is described. Methods used for the recovery and reuse of the target material (54Fe) are also described. The yield of 55Co at 12 MeV incident deuteron energy is 1.7 mCi per mu Ah at end of bombardment and the contamination with 57Co is 0.016%. The 55Co produced is chelated to bleomycin and used for tumour imaging with a positron emission tomographic camera based on multi-wire proportional chamber detectors.


Asunto(s)
Bleomicina , Radioisótopos de Cobalto , Radioquímica/métodos , Humanos , Neoplasias/diagnóstico por imagen , Tomografía Computarizada de Emisión
17.
Br J Urol ; 78(3): 354-7, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8881941

RESUMEN

OBJECTIVE: To report eight cases of limited Wegener's granulomatosis (WG) affecting the urogenital tract (testis, ureter, bladder, urethra and penis) and to emphasize the importance of the anti-neutrophil cytoplasm antibody (ANCA) test in establishing the diagnosis. PATIENTS AND METHODS: Eight patients (six men and two women, aged 41-77 years) were diagnosed with WG, based on their previous medical history, the ANCA test and by biopsy. RESULTS: In each case, there were difficulties and delay in establishing the diagnosis of WG and starting appropriate treatment. The ANCA test was positive in seven cases and helped in establishing the diagnosis, in conjunction with the confirmation of vasculitis and granulomata by biopsy. CONCLUSION: We advocate ANCA testing in patients presenting with limited urogenital disease in association with a past or present relevant history of arthritis, skin vasculitis and/or biopsies showing necrosis or non-specific inflammation.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/análisis , Enfermedades Urogenitales Femeninas/diagnóstico , Granulomatosis con Poliangitis/diagnóstico , Enfermedades Urogenitales Masculinas , Adulto , Anciano , Femenino , Enfermedades Urogenitales Femeninas/complicaciones , Enfermedades Urogenitales Femeninas/terapia , Estudios de Seguimiento , Granulomatosis con Poliangitis/complicaciones , Granulomatosis con Poliangitis/terapia , Humanos , Masculino , Persona de Mediana Edad
18.
Appl Opt ; 29(33): 4938-42, 1990 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-20577488

RESUMEN

Resonance ionization mass spectrometry (RIMS) of neutral atoms sputtered from III-V compound semiconductors such as Al(x)Ga(1-x)As provides information that is complementary to secondary ion mass spectrometry with the added advantages of rejecting mass interferences, retaining good sensitivity, and reducing matrix effects. A GaAs sample, delta doped with Be, is used to measure depth resolution and Be secondary ion and atom yield. Because of the coupling of the pulsed RIMS lasers and continuous sputtering beam, duty cycle factors are used to determine the atom yield. A 3-D model of the geometrical overlap of laser and sputtered atoms is developed to ascertain the same utilization efficiency in RIMS. About 30% of the atoms sputtered in 1 micros are calculated to be in the laser beam. The atom yield was found to be near unity. The time-gated RIMS useful yield is ~2%. RIMS is used to minimize matrix effects in a depth profile of a Be-implanted AlAs/A1(0.2)Ga(0.8)As heterostructure and shows that Be diffuses from higher Al-containing layers at concentrations near 10(19) cm(-3). The atomization of As is shown to be affected by the Al content in a GaAs/Al(0.5)Ga(0.5)As structure.

19.
Breast J ; 9(2): 126-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12603387

RESUMEN

Resection of liver metastases is accepted as an appropriate treatment for colorectal metastases in suitable patients. Liver transplant is not often used for malignant disease as there is a high incidence of undetectable micrometastases elsewhere and recurrence is likely. The effects of immunosuppression may also enhance the growth of malignant cells at other sites. We report a case where a young patient with undiagnosed breast cancer with axillary and liver metastases underwent liver transplantation and is effectively leading a normal life 33 months after transplant.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Lobular/secundario , Carcinoma Lobular/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Lobular/tratamiento farmacológico , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/secundario , Progresión de la Enfermedad , Femenino , Humanos , Terapia Neoadyuvante , Factores de Tiempo
20.
Ann Plast Surg ; 38(5): 518-22, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9160135

RESUMEN

Ectopia cordis is a very rare congenital anomaly associated with a high mortality rate. A successful repair of ectopia cordis with complete absence of sternum was achieved in a two-stage procedure. Initial management consisted of coverage of skin over the malpositioned heart using bilateral pectoral skin flaps. A second more definitive repair was undertaken at age 14 months. Four methyl methacrylate struts were used to reconstruct the anterior chest wall and were then covered with bilateral pectoralis major muscle flaps. At the 2.5-year follow-up there is no evidence of cardiopulmonary compromise and the development of the thorax appears normal. We advise that use of alloplastic materials is a valid option in managing this difficult congenital anomaly.


Asunto(s)
Cardiopatías Congénitas/cirugía , Prótesis e Implantes , Esternón/anomalías , Esternón/cirugía , Cementos para Huesos , Humanos , Lactante , Masculino , Metilmetacrilato , Metilmetacrilatos , Polietilenos , Polipropilenos , Mallas Quirúrgicas
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