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1.
Nature ; 529(7586): 394-8, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26791728

RESUMEN

The nature of inter-group relations among prehistoric hunter-gatherers remains disputed, with arguments in favour and against the existence of warfare before the development of sedentary societies. Here we report on a case of inter-group violence towards a group of hunter-gatherers from Nataruk, west of Lake Turkana, which during the late Pleistocene/early Holocene period extended about 30 km beyond its present-day shore. Ten of the twelve articulated skeletons found at Nataruk show evidence of having died violently at the edge of a lagoon, into which some of the bodies fell. The remains from Nataruk are unique, preserved by the particular conditions of the lagoon with no evidence of deliberate burial. They offer a rare glimpse into the life and death of past foraging people, and evidence that warfare was part of the repertoire of inter-group relations among prehistoric hunter-gatherers.


Asunto(s)
Arqueología , Procesos de Grupo , Violencia/historia , Heridas y Lesiones/historia , Adolescente , Adulto , Niño , Preescolar , Conducta Alimentaria , Femenino , Historia Antigua , Humanos , Kenia , Masculino , Esqueleto , Cráneo/lesiones
3.
Pneumologie ; 63(10): 585-7, 2009 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-19708008

RESUMEN

Small cell carcinomas are most frequently localised within the lung, however, they also may be detected at extrapulmonary sites such as the gastrointestinal tract and the genitourinary tract. The confirmation of a small cell carcinoma outside of the lung may not necessarily indicate the presence of a metastasis, however, it also may represent the primary tumor itself. We present the case of a patient with a small cell carcinoma of the lung with metastases to the stomach. A regression of the primary lung tumor and the disappearance of the gastric metastases could be achieved by chemotherapeutic treatment with carboplatin, etoposide, and vincristine. However, death due to pneumonia occurred 3 months after initial diagnosis. This case illustrates that in rare cases a metastasis from small cell lung cancer may occur in the intestinal tract even without leading to distinctive symptoms.


Asunto(s)
Carcinoma de Células Pequeñas/patología , Neoplasias Pulmonares/patología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/secundario , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Etopósido/administración & dosificación , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Neumonía/inducido químicamente , Neoplasias Gástricas/patología , Vincristina/administración & dosificación
4.
Phys Med Biol ; 60(17): 6811-31, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26301433

RESUMEN

Especially for heavier ions such as carbon ions, treatment planning systems (TPSs) for ion radiotherapy depend on models predicting the relative biological effectiveness (RBE) of the particles involved. Such models are subject to intensive research and the choice of the optimal RBE model is a matter of debate. On the other hand TPSs are often strongly coupled to particular RBE models and transition even to extended models of the same family can be difficult. We present here a model-independent interface which allows the unbiased use of any RBE model capable of providing dose-effect curves (even sampled curves) for a TPS. The full decoupling between the RBE model and TPS is based on the beam-mixing model proposed by Lam which is, in contrast to the often-used Zaider-Rossi model, independent of the explicit form of the underlying dose-effect curves. This approach not only supports the refinement of RBE models without adaptations of the TPS--which we demonstrate by means of the local effect model (LEM)--but also allows the comparison of very different model approaches on a common basis. We exemplify this by a comparison between the LEM and a model from the literature for proton RBE prediction.


Asunto(s)
Supervivencia Celular/efectos de la radiación , Radioterapia de Iones Pesados , Modelos Estadísticos , Planificación de la Radioterapia Asistida por Computador/métodos , Efectividad Biológica Relativa , Programas Informáticos , Animales , Células CHO , Cricetinae , Cricetulus , Relación Dosis-Respuesta en la Radiación , Humanos , Dosis de Radiación
6.
Appl Radiat Isot ; 52(5): 1317-26, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10836449

RESUMEN

In order to determine the components which give rise to the EPR spectrum around g = 2 we have applied Maximum Likelihood Common Factor Analysis (MLCFA) on the EPR spectra of enamel sample 1126 which has previously been analysed by continuous wave and pulsed EPR as well as EPR microscopy. MLCFA yielded agreeing results on three sets of X-band spectra and the following components were identified: an orthorhombic component attributed to CO2-, an axial component (CO3(3-)), as well as four isotropic components, three of which could be attributed to SO2-, a tumbling CO2- and a central line of a dimethyl radical. The X-band results were confirmed by analysis of Q-band spectra where three additional isotropic lines were found, however, these three components could not be attributed to known radicals. The orthorhombic component was used to establish dose response curves for the assessment of the past radiation dose, D(E). The results appear to be more reliable than those based on conventional peak-to-peak EPR intensity measurements or simple Gaussian deconvolution methods.


Asunto(s)
Esmalte Dental/efectos de la radiación , Espectroscopía de Resonancia por Spin del Electrón/métodos , Fósiles , Radiometría/métodos , Animales , Radicales Libres , Funciones de Verosimilitud
7.
Med Klin (Munich) ; 87(3): 113-7, 1992 Mar 15.
Artículo en Alemán | MEDLINE | ID: mdl-1579086

RESUMEN

The thyroid gland of 536 patients of a medical hospital in an iodine deficient area was investigated by ultrasound. According to the sonographic pattern and to the scintigraphic imaging the focal lesions were analysed as micro- or macrofollicular adenomas, autonomous adenomas, cysts and chalk. The prevalence of goitres was 37.7%. The prevalence of goitres was higher in women (45%) than in men (30%). Focal lesions could be observed in 27.6%, equally more often in women (36%) than in men (18.9%). The frequency of focal lesions increased with the age of the patients and with the volume of the thyroid gland. Autonomous adenomas were found three times more often in women than in men. Hyperthyroidism was only observed in patients with nodules larger than 4 cm in diameter. Sonographic screening examinations of the thyroid gland seem to be useful in all patients of a clinic of medicine because of the risk (25%) of iodine contamination by diagnostic measures.


Asunto(s)
Bocio Endémico/epidemiología , Pruebas de Función de la Tiroides , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Alemania/epidemiología , Bocio Endémico/diagnóstico por imagen , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Ultrasonografía
8.
Radiat Prot Dosimetry ; 157(4): 463-76, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23832975

RESUMEN

This work deals with the specific studies of three main sources of uncertainty in electron spin resonance (ESR) dosimetry/dating of fossil tooth enamel: (1) the precision of the ESR measurements, (2) the long-term signal fading the selection of the fitting function. They show a different influence on the equivalent dose (D(E)) estimates. Repeated ESR measurements were performed on 17 different samples: results show a mean coefficient of variation of the ESR intensities of 1.20 ± 0.23 %, inducing a mean relative variability of 3.05 ± 2.29 % in the D(E) values. ESR signal fading over 5 y was also observed: its magnitude seems to be quite sample dependant but is nevertheless especially important for the most irradiated aliquots. This fading has an apparent random effect on the D(E) estimates. Finally, the authors provide new insights and recommendations about the fitting of ESR dose-response curves of fossil enamel with a double saturating exponential (DSE) function. The potential of a new variation of the DSE was also explored. Results of this study also show that the choice of the fitting function is of major importance, maybe more than the other sources previously mentioned, in order to get accurate final D(E) values.


Asunto(s)
Esmalte Dental/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Datación Radiométrica/métodos , Radiometría/métodos , Partículas alfa , Animales , Bovinos , Relación Dosis-Respuesta en la Radiación , Fósiles , Rayos gamma , Caballos , Dosis de Radiación , Procesamiento de Señales Asistido por Computador
9.
Phys Med Biol ; 58(19): 6827-49, 2013 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-24025596

RESUMEN

The relative biological effectiveness (RBE) is a central quantity in particle radiobiology and depends on many physical and biological factors. The local effect model (LEM) allows one to predict the RBE for radiobiologic experiments and particle therapy. In this work the sensitivity of the RBE on its determining factors is elucidated based on monitoring the RBE dependence on the input parameters of the LEM. The relevance and meaning of all parameters are discussed within the formalism of the LEM. While most of the parameters are fixed by experimental constraints, one parameter, the threshold dose Dt, may remain free and is then regarded as a fit parameter to the high LET dose response curve. The influence of each parameter on the RBE is understood in terms of theoretic considerations. The sensitivity analysis has been systematically carried out for fictitious in vitro cell lines or tissues with α/ß = 2 Gy and 10 Gy, either irradiated under track segment conditions with a monoenergetic beam or within a spread out Bragg peak. For both irradiation conditions, a change of each of the parameters typically causes an approximately equal or smaller relative change of the predicted RBE values. These results may be used for the assessment of treatment plans and for general uncertainty estimations of the RBE.


Asunto(s)
Modelos Teóricos , Daño del ADN , Humanos , Fotones/uso terapéutico , Planificación de la Radioterapia Asistida por Computador , Efectividad Biológica Relativa , Incertidumbre
10.
Phys Med Biol ; 57(22): 7261-74, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23075883

RESUMEN

Biological optimization for treatment planning in carbon ion therapy is currently based on the first version of the local effect model (LEM I). Further developments implemented in the latest version (LEM IV) allowed to predict more accurately the Relative Biological Effectiveness (RBE) in-vitro. The main goal of this study is to compare the LEM IV against LEM I under treatment-like conditions for idealized target geometries. Therefore, physical dose distributions resulting from the biological optimization with LEM I were used to recalculate the RBE-weighted dose distribution based on LEM IV. Input parameters representing the clinical endpoints late toxicity in the central nervous system and the tumor control for chordoma were chosen to investigate the impact of changes on the predicted isoeffective dose levels. The recalculated RBE-weighted dose distributions show an increase within the target region, and the mean RBE-weighted dose values are dependent on the geometry and decrease with increasing target dimension. The differences between predictions of LEM IV and LEM I are less than 10% for typical tumor volumes treated in the pilot project at GSI. Median RBE-weighted doses predicted by LEM IV in the target region are consistent with clinically observed dose-response behavior as demonstrated by comparison to the 5-year local control curve for skull base chordoma.


Asunto(s)
Carbono/uso terapéutico , Planificación de la Radioterapia Asistida por Computador/métodos , Humanos , Dosificación Radioterapéutica , Efectividad Biológica Relativa
13.
Z Gastroenterol ; 27(6): 331-4, 1989 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-2505456

RESUMEN

The median plasma concentration of growth hormone (GH) in 63 women with liver cirrhosis was significantly elevated when compared with a control group (4.4 ng/ml vs 1.8 ng/ml, p less than 0.01). In 38% of the patients GH concentration was higher than 6.0 ng/ml. GH correlated significantly with the degree of decompensation of the cirrhosis (Child A-C). It was not influenced by the concentrations of estradiol, estrone, or testosterone. Thyrotropin releasing hormone (TRH) induced paradoxial GH increase (delta-GH) in 23 patients showed no significant difference to the data of the control group (2.7 ng/ml vs 0.8 ng/ml). The etiology of cirrhosis (alcoholic or non alcoholic) proved to be unimportant concerning the GH elevation. A missing correlation of GH to thyroid stimulating hormone (TSH), and of delta-GH to TRH induced increase of TSH (delta-TSH) argues against the hypothesis that latent hypothyroidism - often described in cirrhosis - might be responsible of the GH elevation.


Asunto(s)
Hormona del Crecimiento/sangre , Cirrosis Hepática/sangre , Adulto , Anciano , Estradiol/sangre , Estrona/sangre , Femenino , Hepatitis B/sangre , Degeneración Hepatolenticular/sangre , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática Alcohólica/sangre , Cirrosis Hepática Biliar/sangre , Persona de Mediana Edad , Testosterona/sangre , Tirotropina/sangre , Hormona Liberadora de Tirotropina
14.
Z Gastroenterol ; 23(8): 446-54, 1985 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-3933200

RESUMEN

The median plasma level of prolactin in 94 women with cirrhosis of the liver did not differ significantly when compared with a control group (8,0 versus 7,2 ng/ml). Nevertheless 22% of the investigated women exhibited a plasma prolactin level higher than 15 ng/ml. The prolactin concentrations correlated to the severeness of cirrhosis and in the subgroup with decompensated cirrhosis the prolactin concentrations were found to be significantly elevated (12 ng/ml). Like basal prolactin the TRH-induced prolactin release showed no significant difference between cirrhotic women and controls (36,1 versus 38,5 ng/ml). No difference could be observed between the prolactin concentrations of alcoholic or non alcoholic cirrhotic women, and prolactin did not correlate with estradiol or estrone plasma levels. Other factors than cirrhosis itself (i.e. medical treatment, renal insufficiency, stress) must be discussed as causing hyperprolactinemia in cirrhosis.


Asunto(s)
Hiperprolactinemia/sangre , Cirrosis Hepática/sangre , Prolactina/sangre , Femenino , Encefalopatía Hepática/sangre , Degeneración Hepatolenticular/sangre , Humanos , Cirrosis Hepática Alcohólica/sangre , Cirrosis Hepática Biliar/sangre , Persona de Mediana Edad , Pronóstico , Hormona Liberadora de Tirotropina
15.
Klin Wochenschr ; 63(16): 752-61, 1985 Aug 16.
Artículo en Alemán | MEDLINE | ID: mdl-3930834

RESUMEN

Basal thyroid hormone levels were measured in 68 women with liver cirrhosis (LC) of different etiology (alcoholic n = 34, posthepatitic B n = 9, PBC n = 5, cryptogenetic n = 18, M. Wilson n = 2). In addition the rise of TSH after 400 micrograms TRH was measured in 23 women with LC and compared with the data obtained from 17 women of a control group. There was no difference of the median T4-concentrations (LC 8.0 micrograms/dl versus 7.2 micrograms/dl) but a significant correlation of T4 to the grade of decompensation of LC. In contrast of T4 there was a marked decrease of T3 in LC-patients (109 ng/dl versus 143 ng/dl) and a rise of reverse T3 (0.21 ng/ml versus 0.13 ng/ml). The decrease of T3 and rise of reverse T3 equally correlated to the severeness of LC. TBG concentrations fell according to the grade of decompensation of LC and T4/TBG-quotient exhibited no difference to the control data (0.51 both). Though basal thyroid hormones and TSH show euthyroidism the significant augmented TSH release after TRH (delta-TSH 7.0 versus 3.2 microU/ml) indicate a status of latent hypothyroidism. In alcoholic cirrhosis the degree of TSH release was much higher than in non alcoholic cirrhosis. Estradiol and estrone levels correlated significantly negatively to T4, T3, estrone negatively to TBG and positively to reverse T3 but not to TSH and TSH release. Otherwise TSH release correlated positively to estradiol. The thyroid status in women with liver cirrhosis does not differ from the thyroid hormone profile found in men with cirrhosis.


Asunto(s)
Cirrosis Hepática/sangre , Hormonas Tiroideas/sangre , Femenino , Degeneración Hepatolenticular/sangre , Humanos , Cirrosis Hepática Alcohólica/sangre , Cirrosis Hepática Biliar/sangre , Persona de Mediana Edad , Tirotropina/sangre , Hormona Liberadora de Tirotropina , Tiroxina/sangre , Proteínas de Unión a Tiroxina/metabolismo , Triyodotironina/sangre , Triyodotironina Inversa/sangre
16.
J Hum Evol ; 40(6): 467-82, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11371150

RESUMEN

In view of a decade of progress in ESR dating we have revised the ESR chronology of Border Cave. A detailed gamma ray survey in 1994 and newly calculated beta attenuation data led to total dose rate estimations that are between 0 and 30% smaller than previously estimated. Accordingly, the resulting ESR age estimates are between 0 and 30% older. The ESR dates are now in good agreement with independent age estimates, particularly(14)C and amino acid racemization. New ESR dates for the lowermost dated sedimentary layer, 5 WA (white ash), indicate that the sedimentation of the sequence started around 200 ka ago.


Asunto(s)
Esmalte Dental , Espectroscopía de Resonancia por Spin del Electrón/métodos , Fósiles , Hominidae , Animales , Sedimentos Geológicos/química , Humanos , Análisis de Regresión
17.
Klin Wochenschr ; 65(9): 411-8, 1987 May 04.
Artículo en Alemán | MEDLINE | ID: mdl-3110486

RESUMEN

The hormonal status of men with cirrhosis of the liver has been investigated in numerous studies. Little, however, is known about changes of sexual hormones in women afflicted by this disorder. In a study of 31 postmenopausal women (mean age 63 +/- 8 years) suffering from cirrhosis of various etiology (alcoholic, n = 8; posthepatitic B, n = 1; PBC, n = 5; cryptogenetic, n = 17) the blood levels of estradiol (E2), estrone (E1), androstenedione (A), testosterone (T) and basal and stimulated values of gonadotropins are reported and compared with the data obtained in an age-matched control group (n = 9). In cirrhosis a significant increase of the median E2 (28 vs 12 pg/ml, P less than 0.01) was found, whereas the changes of the blood levels of E1 (88 vs 76 pg/ml), A (63 vs 111 ng/dl), and T (0.30 vs 0.15 ng/ml) did not attain statistical significance in comparison to controls. Within the study group, however, a significant positive correlation with the degree of decompensation of cirrhosis (Childscore A-C) was observed for the steroid hormones measured. Thus, in subgroup C the hormone levels are higher than physiologically expected for postmenopausal women. On the other hand the median FSH (32 vs 48 mU/ml, P less than 0.05) is significantly lower in cirrhosis compared to controls with a trend to decreased values of LH. Very low levels of LH and FSH are found in decompensated cirrhosis. The decrease of LH and FSH can partly be explained by the rise of peripheral hormones (i.e. E2, E1, and in some cases T and A).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hormonas Esteroides Gonadales/sangre , Menopausia/sangre , Ovario/fisiopatología , Hipófisis/fisiopatología , Androstenodiona/sangre , Estradiol/sangre , Estrona/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Persona de Mediana Edad , Hormonas Liberadoras de Hormona Hipofisaria , Testosterona/sangre
18.
Philos Trans R Soc Lond B Biol Sci ; 337(1280): 145-8, 1992 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-1357688

RESUMEN

Many materials found in archaeological sites are able to trap electronic charges as a result of bombardment by radioactive radiation from the surrounding sediment. The presence of these trapped charges can be detected by electron spin resonance (ESR) spectroscopy: the intensity of the ESR signal is a measure of the accumulated dose and thus of the age. Tooth enamel is ubiquitous at archaeological sites and is well suited for ESR dating, with a precision of about 10-20%. This method has now been used to date many sites critical to the biological and cultural evolution of modern man. Dates for sites in Israel and Africa have demonstrated the existence of anatomically modern humans more than 100 ka ago.


Asunto(s)
Evolución Biológica , Hominidae , Tiempo , Animales , Espectroscopía de Resonancia por Spin del Electrón/métodos , Humanos , Mediciones Luminiscentes
19.
Ultraschall Med ; 6(1): 13-8, 1985 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-2859654

RESUMEN

A total of 15 patients with parathyroid tumours were scanned preoperatively using high-resolution real-time sonography (7 MHz). Of these, 14 had a single adenoma or primary hyperplasia, one had a carcinoma. In 13 out of 15 patients the echogenicity of the parathyroid tumours was consistently less than of the adjacent normal thyroid tissue; in 2 out of 15 cases parathyroid neoplasms were barely distinguishable in echogenicity from thyroid tissue. No specific echomorphologic differences were proved to exist between primary parathyroid hyperplasia, adenoma or carcinoma. The smallest parathyroid neoplasia in this study detected by sonography measured 5 x 8 mm in diameter. The value and limits of parathyroid sonography were discussed with regard to our own experience and the reports in the literature.


Asunto(s)
Neoplasias de las Paratiroides/diagnóstico , Ultrasonografía , Adenoma/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Hiperplasia , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple/diagnóstico , Glándulas Paratiroides/patología
20.
Cancer ; 55(3): 624-30, 1985 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-2856898

RESUMEN

Ultrasound screening in 9 and 21 members, respectively, of two families affected by familial C-cell carcinoma, as well as sonographic findings in 6 patients with sporadic medullary carcinoma of the thyroid (MCT), are reported. Unilateral and bilateral tumor nodules were identified by sonography in 12 of a total of 13 patients with MCT (n = 9) or local tumor recurrence following thyroidectomy (n = 4); one carcinoma, 3 X 6 mm in diameter, was missed. Nine of the 12 (75%) were clinically occult, nonpalpable C-cell carcinomas. The smallest occult MCT correctly diagnosed by ultrasound had a diameter of 4 mm. A positive correlation was found between the sonographically determined tumor mass (number/size of nodules/metastases) and the plasma calcitonin level. Pheochromocytomas were diagnosed by ultrasound as part of a multiple endocrine neoplasia (MEN IIa) in two patients with MCT. The echomorphologic findings of the intrathyroid C-cell carcinomas and their metastases display characteristic but nonspecific features. Sonographic findings on these tumors should therefore not be interpreted without consideration of plasma calcitonin assays.


Asunto(s)
Carcinoma/diagnóstico , Neoplasia Endocrina Múltiple/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Ultrasonografía , Adolescente , Adulto , Calcitonina/sangre , Carcinoma/sangre , Carcinoma/genética , Niño , Femenino , Estudios de Seguimiento , Humanos , Hiperplasia/diagnóstico , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple/sangre , Neoplasia Endocrina Múltiple/genética , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Linaje , Pentagastrina , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/genética , Tiroidectomía
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