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1.
Phys Rev Lett ; 101(2): 022303, 2008 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-18764175

RESUMEN

We present a measurement of the spin-dependent cross sections for the 3He over -->(e over -->,e')X reaction in the quasielastic and resonance regions at a four-momentum transfer 0.1< or =Q2< or =0.9 GeV2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region.

2.
Vox Sang ; 89(1): 39-43, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15938738

RESUMEN

BACKGROUND AND OBJECTIVES: Serological evaluation of maternal sera for platelet antibodies in suspected fetal/neonatal alloimmune thrombocytopenia (FNAITP) discloses in only approximately 30% of individuals a platelet-specific antibody. Transfusion-induced alloimmunization against human platelet antigen-15 (HPA-15) has been reported to be about as common as against HPA-5, the second most common platelet antibody. Thus, anti-HPA-15 may also contribute significantly to yet-unclear cases of FNAITP. MATERIALS AND METHODS: In this retrospective analysis, we provide data on maternal platelet antibodies from 309 mothers who delivered an offspring with suspected FNAITP. RESULTS: Genotyping maternal and paternal samples (together n = 573) revealed a gene frequency of 0.496 for HPA-15a and a gene frequency of 0.504 for HPA-15b. HPA-15 antibodies were detected in 2% of all samples. Anti-HPA-15a and -15b were detected in two and three samples, respectively. One serum reacted equally with HPA-15a and -15b platelets. The most frequent platelet-specific antibodies were anti-HPA-1a (22%), but anti-HPA-5b (8.4%) were more frequent than anti-HPA-15. In addition, panreactive (5.5%) or autoreactive (5.2%) anti-GPIIb/IIIa or anti-GPIb/IX were detectable in maternal samples. CONCLUSIONS: These data indicate that HPA-15 alloimmunization needs only to be considered in subjects with suspected FNAITP if no other platelet-specific antibody is detectable. The presence of panreactive or autoreactive antibodies should also be considered in neonatal thrombocytopenia.


Asunto(s)
Antígenos CD/inmunología , Plaquetas/inmunología , Enfermedades Fetales/inmunología , Intercambio Materno-Fetal/inmunología , Proteínas de Neoplasias/inmunología , Trombocitopenia/inmunología , Antígenos CD/genética , Autoanticuerpos/sangre , Femenino , Proteínas Ligadas a GPI , Frecuencia de los Genes , Humanos , Inmunización , Incidencia , Recién Nacido , Isoanticuerpos/sangre , Masculino , Proteínas de Neoplasias/genética , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/inmunología , Complejo GPIb-IX de Glicoproteína Plaquetaria/inmunología , Embarazo , Estudios Retrospectivos
3.
Phys Rev Lett ; 93(15): 152301, 2004 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-15524867

RESUMEN

The generalized forward spin polarizabilities gamma(0) and delta(LT) of the neutron have been extracted for the first time in a Q2 range from 0.1 to 0.9 GeV2. Since gamma(0) is sensitive to nucleon resonances and delta(LT) is insensitive to the Delta resonance, it is expected that the pair of forward spin polarizabilities should provide benchmark tests of the current understanding of the chiral dynamics of QCD. The new results on delta(LT) show significant disagreement with chiral perturbation theory calculations, while the data for gamma(0) at low Q2 are in good agreement with a next-to-leading-order relativistic baryon chiral perturbation theory calculation. The data show good agreement with the phenomenological MAID model.

4.
Phys Rev Lett ; 93(12): 122001, 2004 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-15447252

RESUMEN

We report a virtual Compton scattering study of the proton at low c.m. energies. We have determined the structure functions P(LL)-P(TT)/epsilon and P(LT), and the electric and magnetic generalized polarizabilities (GPs) alpha(E)(Q2) and beta(M)(Q2) at momentum transfer Q(2)=0.92 and 1.76 GeV2. The electric GP shows a strong falloff with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a falloff; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from piN intermediate states.

5.
Phys Rev Lett ; 92(9): 091801, 2004 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-15089459

RESUMEN

We observe a net beam excess of 8.7+/-6.3(stat)+/-2.4(syst) events, above 160 MeV, resulting from the charged-current reaction of nu(micro) and/or nu;(mu) on C and H in the LSND detector. No beam-related muon background is expected in this energy regime. Within an analysis framework of pi(0)-->nu(mu)nu;(mu), we set a direct upper limit for this branching ratio of Gamma(pi(0)-->nu(mu)nu;(mu))/Gamma(pi(0)-->all)<1.6 x 10(-6) at 90% confidence level.

6.
Phys Rev Lett ; 92(2): 022301, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14753931

RESUMEN

We have measured the spin structure functions g(1) and g(2) of 3He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.058 GeV off a polarized 3He target at a 15.5 degrees scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the Q2 evolution of Gamma(1)(Q2)= integral (1)(0)g(1)(x,Q2)dx, Gamma(2)(Q2)= integral (1)(0)g(2)(x,Q2)dx, and d(2)(Q2)= integral (1)(0)x(2)[2g(1)(x,Q2)+3g(2)(x,Q2)]dx for the neutron in the range 0.1< or =Q2< or =0.9 GeV2 with good precision. Gamma(1)(Q2) displays a smooth variation from high to low Q2. The Burkhardt-Cottingham sum rule holds within uncertainties and d(2) is nonzero over the measured range.

7.
Phys Rev Lett ; 89(24): 242301, 2002 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-12484938

RESUMEN

We present data on the inclusive scattering of polarized electrons from a polarized 3He target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5 degrees. Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference sigma(1/2)-sigma(3/2). We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q2 of 0.1-0.9 GeV2.

9.
Ultrasound Obstet Gynecol ; 18(5): 515-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11844175

RESUMEN

OBJECTIVE: The main arteries to the breast are the lateral thoracic artery and to a lesser extent the internal thoracic artery. In this prospective open diagnostic study involving 94 women, we compared the intraindividual differences of Doppler indices in the lateral thoracic (breast-feeding) artery of breasts affected by cancer with those unaffected by disease. METHODS: Sixty-seven consecutive patients were recruited from an outpatient unit for breast surgery and 27 volunteers were studied who were known to be without any breast disease (controls). In each patient we attempted to obtain Doppler indices from the lateral thoracic artery of both breasts. The difference in Doppler indices in each individual was assessed and statistical analysis was performed to assess whether these differences were significantly altered in women with cancer compared to healthy women. RESULTS: Lateral thoracic arteries could be visualized in 88% of the study population. Significantly lower values for pulsatility and resistance indices and systolic/diastolic ratios were obtained in the lateral thoracic arteries of breasts affected by cancer as compared to the contralateral breasts (1.73 +/- 0.39 vs. 2.05 +/- 0.47, P = 0.003; 0.78 +/- 0.06 vs. 0.84 +/- 0.06, P < 0.0001; 4.71 +/- 1.24 vs. 6.75 +/- 3.38, P = 0.0008, respectively). Using the intraindividual difference of pulsatility index, resistance index and systolic/diastolic ratio to screen for malignancy, sensitivities for breast cancer of 78%, 85% and 83%, respectively, were achieved. Depending on the cut-off level, specificity reached 94%. CONCLUSION: The intraindividual difference in Doppler indices in women with breast cancer may be a useful test for the diagnosis of breast lesions.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Arterias Torácicas/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Mama/irrigación sanguínea , Neoplasias de la Mama/irrigación sanguínea , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Flujo Pulsátil , Sensibilidad y Especificidad , Resistencia Vascular
12.
Z Geburtshilfe Neonatol ; 203(4): 161-5, 1999.
Artículo en Alemán | MEDLINE | ID: mdl-10483698

RESUMEN

BACKGROUND: The effectiveness of Indian version to convert fetuses from breech to vertex presentation was evaluated. METHODS: One hundred and nine pregnant women presenting between 30 and 32 weeks of gestation with singleton breech infants were included in our prospective randomized open study making an interim analysis recruitment to estimate the sample sizes after one year. The spontaneous version rate of fetuses in breech presentation was compared with the version rate in women performing Indian version. Indian version is a maternal positioning exercise that consists of raising the pelvis, abduction of the thighs, and relaxed abdominal breathing. Clinical parameters that could influence the result were assessed. RESULTS: In primiparous women, the version rate was 70% in the Indian version group and 63% in the comparison group. In multiparous women, 89% Indian versions and 87% spontaneous versions were observed. Parity was the only clinical parameter found to be related to outcome. CONCLUSION: Indian version does not significantly improve the rate of spontaneous version of breech to vertex presentation.


Asunto(s)
Presentación de Nalgas , Terapia por Ejercicio , Versión Fetal , Adulto , Femenino , Humanos , Recién Nacido , Paridad , Embarazo , Tercer Trimestre del Embarazo , Resultado del Tratamiento
13.
Br J Cancer ; 80(5-6): 874-8, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10360668

RESUMEN

Regular screening mammographies and increasing knowledge of high-risk groups have resulted in an improvement in the rate of detection of smaller malignant lesions. However, uncertain minimal mammographic features frequently require further costly and often uncomfortable investigation, including repeat radiological controls or surgical procedures, before cancerous lesions can be identified. Placental isoferritin (p43), a protein with immunosuppressive effects, has been detected on the surface of lymphocytes taken from peripheral blood in patients with breast cancer. In this study we evaluated the sensitivity and specificity of the expression of p43-positive lymphocytes as a marker in early stage breast cancer and also investigated its expression on T-cell subpopulations. The presence of p43-positive lymphocytes was investigated using the monoclonal antibody CM-H-9 and flow cytometry in 76 women with controversial, non-palpable mammographic findings who were undergoing surgical biopsy. Patients with early breast cancer (n = 48) had significantly higher p43-positive cell values (median 3.83%, range 0.98-19.4) than patients with benign lumps (n = 28, median 1.43%, range 0.17-3.7) or controls (n = 22, median 1.3%, range 0.4-1.87) (P < 0.0001). At a cut-off level of 2% p43-positive cells a sensitivity of 91.7% and a specificity of 89.3% for detection of breast cancer could be reached. While the median ratio of total CD4+/CD8+ cells was 2.6, a ratio of 1.3 was found for the p43-positive subpopulation (P < 0.001), thus indicating a significant link between p43 and CD8+ cells. The determination of p43-positive lymphocytes in peripheral blood could serve as an additional diagnostic tool in patients with controversial mammographic findings and could also reduce the need for cost-intensive and often uncomfortable management of these patients.


Asunto(s)
Antígenos de Neoplasias/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/diagnóstico , Carcinoma in Situ/sangre , Carcinoma in Situ/diagnóstico , Carcinoma Ductal de Mama/sangre , Carcinoma Ductal de Mama/diagnóstico , Subgrupos Linfocitarios/metabolismo , Factor Tu de Elongación Peptídica/sangre , Biomarcadores de Tumor/sangre , Enfermedades de la Mama/sangre , Enfermedades de la Mama/diagnóstico , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Método Doble Ciego , Femenino , Humanos , Proteínas Mitocondriales , Sensibilidad y Especificidad
14.
Gynecol Oncol ; 72(3): 418-20, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10053116

RESUMEN

Recent reports consider 99mTc-tetrofosmin scintigraphy to be a powerful new diagnostic tool for discriminating malignant from benign breast disease. We report on a woman suffering from histologically confirmed axillary metastases of a primary unknown, occult carcinoma, whose origin was suspected within the breast. All the diagnostic procedures performed to discover any lesion failed or were inconclusive. The primary cancer was clearly visualized, however, in the right breast by means of 99mTc-tetrofosmin scintigraphy. Conclusion. We suggest that 99mTc-tetrofosmin scintigraphy is a powerful method to detect breast cancer, especially when other diagnostic imaging procedures are inconclusive.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Axila , Neoplasias de la Mama/patología , Diagnóstico Diferencial , Femenino , Humanos , Metástasis Linfática/diagnóstico por imagen , Persona de Mediana Edad , Neoplasias Primarias Desconocidas/patología , Tomografía Computarizada de Emisión de Fotón Único
15.
Artículo en Alemán | MEDLINE | ID: mdl-10629382

RESUMEN

OBJECTIVE: Maternal immunoreaction against the embryo can be responsible for fetal growth retardation. The secretion of PLF during pregnancy could be reliable for a diminished immunoreaction of maternal lymphocytes against the embryo. The aim of the present study was to elucidate a possible correlation between PLF and fetal growth retardation. METHODS: In this study, blood samples of 402 pregnant women were obtained between the 12th and 16th weeks of gestation. The serum levels of PLF were compared with birth weight, percentile of birth weight, and gestational age. RESULTS: Women with children whose birth weight was below or equal to the 10th percentile for gestational age showed significantly lower PLF levels (11.4 U/ml, n = 107) as compared with women whose newborns were of normal weight (19.9 U/ml, n = 295; p < 0.004). CONCLUSION: Determination of the PLF level could serve to identify women at risk of having growth-retarded babies.


Asunto(s)
Ferritinas/sangre , Retardo del Crecimiento Fetal/diagnóstico , Placenta/inmunología , Peso al Nacer , Femenino , Retardo del Crecimiento Fetal/inmunología , Edad Gestacional , Humanos , Técnicas para Inmunoenzimas , Recién Nacido , Masculino , Embarazo , Embarazo de Alto Riesgo , Diagnóstico Prenatal
16.
Breast Cancer Res Treat ; 50(2): 125-34, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9822217

RESUMEN

Tumor samples of 240 patients with primary breast cancer were biochemically and immunohistochemically investigated for estrogen receptors (ER) and, in 130 of the samples, for progesterone-receptors (PgR) in order to examine reasons for discordant findings. The biochemical (DCCA) and immunohistochemical assays (ICA) yielded positivity in 71% for ER, and in 44% for PgR. Concordant ER-DCCA and ER-ICA results were obtained in 84%; two thirds of the discordant ER-findings manifested as DCCA-neg/ICA-pos. Concordance in the case of PgR amounted to 72%, and of the discordances 60% were DCCA-neg/ICA-pos. Significant association with postmenopausal status existed only for ER positivity in ICA (p = 0.01), whereas ER-DCCA, PgR-DCCA and PgR-ICA were all more or less independent of the menopausal status. The frequency of discordances was independent of menopausal status. Discordance for ER-assays increased significantly near the respective cut-off point; this was not unequivocally true for PgR-assays. The correlation of tumor types of sparse cellularity, as well as prominent stroma content ('scirrhous carcinoma') with increased frequency of the constellation DCCA-neg/ICA-pos was of borderline significance for PgR (p = 0.06), but not for ER. The percentage of discordant ER-findings, figuring as DCCA-neg/ICA-pos, was statistically significantly increased in locally advanced breast cancer (p = 0.03). Fibrocystic disease in peritumoral breast tissue had no impact on receptor-assay discordance. In any case, the models derived from theoretical thought, laboratory data and singular observations can only in part explain the discordance in steroid receptor values measured with different methods.


Asunto(s)
Neoplasias de la Mama/química , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Factores de Confusión Epidemiológicos , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad
18.
Prenat Diagn ; 16(7): 641-6, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8843474

RESUMEN

The secretion of placental isoferritin (PLF) during pregnancy could be responsible for the diminished immunoreaction of maternal lymphocytes against the embryo. In this study, serum levels of PLF in 335 pregnant women were correlated with birth weight, percentile of birth weight, gestational age, and pulsatility index of the uterine artery, as well as with diastolic notching. Women with small-for-gestational age (SGA) infants (birth weight below or equal to the tenth percentile) showed significantly lower PLF levels (11.7 U/ml) compared with women whose newborns were of normal weight (19.4 U/ml) (P < 0.05). In line with this finding, a strong correlation was observed between PLF levels and the percentile of birth weight, pulsatility index of the uterine artery, and the presence of diastolic notching. The strong correlation of low PLF values and SGA newborns suggests that determination of PLF could serve as a marker to identify women at risk of having such babies.


Asunto(s)
Citocinas/metabolismo , Ferritinas/metabolismo , Retardo del Crecimiento Fetal/diagnóstico , Placenta/metabolismo , Útero/irrigación sanguínea , Adolescente , Adulto , Arterias/fisiología , Peso al Nacer , Citocinas/sangre , Femenino , Ferritinas/sangre , Humanos , Análisis Multivariante , Embarazo , Flujo Pulsátil , Curva ROC , Sensibilidad y Especificidad , Útero/fisiología
19.
Ann Thorac Surg ; 61(5): 1525-6, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8633975

RESUMEN

A 44-year-old man with clinical T2 N0 M0 squamous cell carcinoma of the lung presented 4 weeks after left pneumonectomy with a single metastasis to his right pectoralis major muscle. Three years after excision and chemotherapy he remains in remission. Muscle metastasis of carcinoma is an infrequent occurrence. Further investigation into the incidence and treatment is warranted.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Neoplasias Pulmonares/patología , Enfermedades Musculares/etiología , Neoplasias de los Tejidos Blandos/secundario , Adulto , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Humanos , Neoplasias Pulmonares/cirugía , Masculino , Enfermedades Musculares/patología , Neumonectomía , Neoplasias de los Tejidos Blandos/patología
20.
Geburtshilfe Frauenheilkd ; 56(4): 209-13, 1996 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-8682287

RESUMEN

S.R., a 66-year old woman, was referred to our department because of an axillary mass in the right side. The patient had observed an increasing, painless swelling in the right axilla for the last two months. In the region of the right axilla in the middle axillary line an ovoid and solid tumour of 3 cm in diameter, quite well distinguishable, moving against the skin and the surrounding tissue, could be palpated. A subsequent mammography yielded an unsuspicious visualisation of both breasts and the left axilla. In the right axilla a circular solidification was detected, which then turned out on ultrasound examination to be a 2.6-cm diameter axillary lymph node. In the course of the lymph node extirpation of the right axilla two lymph nodes were dissected with histological evidence of metastatic nodes of a solid tumour, most likely in accordance with a breast carcinoma. Several immunohistochemical methods had been applied to determine the origin of the tumour cells and were thus identified as breast cancer cells. To detect primary causative carcinoma, different examinations were performed postoperatively without identifying any cancerous lesions. At least accurate research concerning the history of the patient was required to reexamine the histologic material of an operation of the right breast in 1989. The histological diagnosis of the dissected node of that time had been defined as a benign intracanaliculary papilloma in the right side without evidence of malignancy. The reexamination of the paraffin-embedded material from the operation of the right breast in 1989 revealed a lobular carcinoma of the right breast. The "occult" (undetectable) carcinoma of the breast occurs in less than 1% of all breast carcinomas. Thus it represent a rare clinical event and hence no standardised therapy schemata exist. To confirm the diagnosis of an occult carcinoma of the breast efficient reexamination of histological material from earlier breast operations indicated.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Metástasis Linfática/diagnóstico , Neoplasias Primarias Desconocidas/diagnóstico , Anciano , Axila , Mama/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Diagnóstico Diferencial , Diagnóstico por Imagen , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Neoplasias Primarias Desconocidas/patología , Neoplasias Primarias Desconocidas/cirugía
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