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1.
Science ; 383(6685): 898-903, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38386759

RESUMEN

The nearby Supernova 1987A was accompanied by a burst of neutrino emission, which indicates that a compact object (a neutron star or black hole) was formed in the explosion. There has been no direct observation of this compact object. In this work, we observe the supernova remnant with JWST spectroscopy, finding narrow infrared emission lines of argon and sulfur. The line emission is spatially unresolved and blueshifted in velocity relative to the supernova rest frame. We interpret the lines as gas illuminated by a source of ionizing photons located close to the center of the expanding ejecta. Photoionization models show that the line ratios are consistent with ionization by a cooling neutron star or a pulsar wind nebula. The velocity shift could be evidence for a neutron star natal kick.

2.
Science ; 262(5130): 86-9, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17742963

RESUMEN

Much of the interstellar gas resides in photodissociation regions whose chemistry and energy balance is controlled by the flux of far-ultraviolet radiation upon them. These photons can ionize and dissociate molecules and heat the gas through the photoelectric effect working on dust grains. These regions have been extensively modeled theoretically, but detailed observational studies are few. Mapping of the prominent Orion Bar photodissociation region at wavelengths corresponding to the carbon-hydrogen stretching mode of polycyclic aromatic hydrocarbons, the 1-0 S(1) line of molecular hydrogen, and the J = 1-0 rotational line of carbon monoxide allows the penetration of the far-ultraviolet radiation into the cloud to be traced. The results strongly support the theoretical models and show conclusively that the incident far-ultraviolet radiation field, not shocks as has sometimes been proposed, is responsible for the emission in the Orion Bar.

3.
Virus Res ; 227: 15-22, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-27697452

RESUMEN

The young pigeon disease syndrome (YPDS) affects mainly young pigeons of less than one year of age and leads to crop stasis, vomitus, diarrhea, anorexia and occasionally death. This disease is internationally a major health problem because of its seasonal appearance during competitions such as homing pigeon races or exhibitions of ornamental birds. While the etiology of YPDS is still unclear, adenoviruses are frequently discussed as potential causative agents. Electron microscopy of feces from a YPDS outbreak revealed massive shedding of adenovirus-like particles. Whole genome sequencing of this sample identified a novel adenovirus tentatively named pigeon adenovirus 2 (PiAdV-2). Phylogenetic and comparative genome analysis suggest PiAdV-2 to belong to a new species within the genus Aviadenovirus, for which we propose the name Pigeon aviadenovirus B. The PiAdV-2 genome shares 54.9% nucleotide sequence identity with pigeon adenovirus 1 (PiAdV-1). In a screening of further YPDS-affected flocks two variants of PiAdV-2 (variant A and B) were detected which shared 97.6% nucleotide identity of partial polymerase sequences, but only 79.7% nucleotide identity of partial hexon sequences. The distribution of both PiAdV-2 variants was further investigated in fecal samples collected between 2008 and 2015 from healthy or YPDS-affected racing pigeons of different lofts. Independent of their health status, approximately 20% of young and 13% of adult pigeon flocks harbored PiAdV-2 variants. Birds were free of PiAdV-1 or other aviadenoviruses as determined by PCRs targeting the aviadenovirus polymerase or the PiAdV-1 fiber gene, respectively. In conclusion, there is no indication of a correlation between YPDS outbreaks and the presence of PiAdV-2 or other aviadenoviruses, arguing against an causative role in this disease complex.


Asunto(s)
Aviadenovirus/clasificación , Aviadenovirus/genética , Columbidae/virología , Animales , Animales Domésticos , Aviadenovirus/ultraestructura , Secuencia de Bases , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/virología , Biología Computacional/métodos , Orden Génico , Genes Virales , Genoma Viral , Genómica/métodos , Alemania , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Reacción en Cadena de la Polimerasa
4.
Plant Cell Rep ; 19(3): 235-240, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30754901

RESUMEN

Embryo axes of four accessions of chickpea (Cicer arietinum L.) were treated with Agrobacterium tumefaciens strains C58C1/GV2260 carrying the plasmid p35SGUSINT and EHA101 harbouring the plasmid pIBGUS. In both vectors the GUS gene is interrupted by an intron. After inoculation shoot formation was promoted on MS medium containing 0.5 mg/l BAP under a selection pressure of 100 mg/l kanamycin or 10 mg/l phosphinothricin, depending on the construct used for transformation. Expression of the chimeric GUS gene was confirmed by histochemical localization of GUS activity in regenerated shoots. Resistant shoots were grafted onto 5-day-old dark-grown seedlings, and mature plants could be recovered. T-DNA integration was confirmed by Southern analysis by random selection of putative transformants. The analysis of 4 plantlets of the T1 progeny revealed that none of them was GUS-positive, whereas the presence of the nptII gene could be detected by polymerase chain reaction.

5.
Rofo ; 127(2): 123-6, 1977 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-143403

RESUMEN

Liver and spleen scanning is a safe, fast and noninvasive diagnostic procedure. With the advent of mobile Gamma Cameras it can be ideally performed in a casualty department. The number of patients with traumatic blunt injuries to the abdomen is increasing and in correlation with the increased speed and concentration of traffic. In eleven patients with ages ranging between 4 and 23, and under observation for violent trauma to the abdomen, liver and spleen scanning was performed either as an emergency procedure or as a follow-up study. Very useful information was obtained regarding the integrety of these organs, before and or after emergency surgical treatment.


Asunto(s)
Traumatismos Abdominales/diagnóstico por imagen , Hígado/diagnóstico por imagen , Bazo/diagnóstico por imagen , Adolescente , Adulto , Niño , Preescolar , Humanos , Hígado/lesiones , Masculino , Cintigrafía , Rotura , Bazo/lesiones , Tecnecio
6.
Minerva Med ; 69(58): 3951-9, 1978 Nov 30.
Artículo en Italiano | MEDLINE | ID: mdl-740285

RESUMEN

Biochemical tests (serum calcium, inorganic phosphate and alkaline phosphatase), as well as clinical, radiological, scanning and histological investigations were undertaken in 24 patients in chronic renal failure. The frequency with which the diagnosis of renal osteopathy could be made depended in the method of investigation, the biochemical findings proving to be completely unreliable. There were positive radiological signs in ten patients and clinical signs in 12, predominantly in the progressive stages of osteopathy. A positive scan was obtained in 23 patients, typical histological bone changes in an equal number. Since it correlates so well with the histological findings, bone scan is suitable particularly in the early diagnosis of osteopathy. Since this test is easily performed and hardly stresses the patient, it should routinely be the initial one for the diagnosis of renal osteopathy.


Asunto(s)
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico por imagen , Fallo Renal Crónico/diagnóstico por imagen , Adulto , Huesos/patología , Femenino , Humanos , Enfermedades Renales/complicaciones , Enfermedades Renales/diagnóstico por imagen , Enfermedades Renales/patología , Masculino , Persona de Mediana Edad , Osteomalacia/etiología , Osteomalacia/patología , Cintigrafía
7.
Nuklearmedizin ; 52(3): 71-80, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23483137

RESUMEN

UNLABELLED: T stage was redefined for patients with differentiated thyroid carcinoma (DTC) between the 5th and 7th versions of the UICC tumour classification system. PATIENTS, METHODS: 636 patients (486 women, 150 men; mean age 49.1 ± 15.6 years, mean follow-up 4.6 years) who had been treated with ablative radioiodine therapy after thyroidectomy for papillary (PTC) or follicular thyroid carcinomas (FTC) were retrospectively assessed on occurrence of locoregional recurrent disease, or cervical lymph node or distant metastases. Disease-free survival was calculated from initial T stage, classified according to both versions of the UICC staging system and compared with the prognostic value of primary tumour size. Kaplan-Meier method and two measures of explained variation, (1) R2 based on the (partial) likelihood ratio statistic of the Cox proportional hazards model and (2) a model-free variant of a distance measure proposed by Schemper had the aim to detect the most advantageous classification. RESULTS: Of the 508 patients with PTC, 11 (2.2%) developed a local recurrence, 37 (7.3%) cervical lymph node and 23 (4.5%) distant metastases, 3 (2.3%), 8 (6.3%), and 18 (14.1%) were the numbers for the 128 FTC patients respectively. The two classification systems yielded an equal count of statistically significant differences regarding disease-free survival in patients with PTC while UICC 7th classification appeared slightly advantageous in patients with FTC. Regarding explained variation the UICC 7th classification tended to be superior to the UICC 5th classification, both in PTC and FTC, however statistical significance was not reached. CONCLUSION: The primary tumour size significantly added to the prognosis regarding local cervical and distant metastases.


Asunto(s)
Adenocarcinoma Folicular/mortalidad , Adenocarcinoma Folicular/patología , Adenocarcinoma Papilar/mortalidad , Adenocarcinoma Papilar/patología , Recurrencia Local de Neoplasia/mortalidad , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología , Adenocarcinoma Folicular/radioterapia , Adenocarcinoma Papilar/radioterapia , Adulto , Anciano , Diagnóstico Diferencial , Supervivencia sin Enfermedad , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Prevalencia , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Análisis de Supervivencia , Tasa de Supervivencia , Neoplasias de la Tiroides/radioterapia , Resultado del Tratamiento , Carga Tumoral
8.
Artículo en Alemán | MEDLINE | ID: mdl-22911260

RESUMEN

The case report describes the successful surgical treatment of an incarcerated hiatal hernia in a 3.5-year-old cat. The animal was presented due to a bad general condition and massive vomiting. Based on clinical examination and diagnostic imaging, laparotomy was performed, revealing a hiatal herniation of the stomach. After reposition and gastropexy, the cat recovered well. She was unremarkable on clinical and radiological follow-up examinations and remained free of gastrointestinal symptoms according to the owner's statement 6 months postoperatively. This case report shows that the described surgical technique is promising in cats with hiatal hernia.


Asunto(s)
Enfermedades de los Gatos/cirugía , Hernia Hiatal/veterinaria , Animales , Enfermedades de los Gatos/diagnóstico por imagen , Gatos , Femenino , Gastropexia/veterinaria , Hernia Hiatal/diagnóstico por imagen , Hernia Hiatal/cirugía , Radiografía , Resultado del Tratamiento
9.
Science ; 333(6047): 1258-61, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21737700

RESUMEN

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts.

13.
Wien Med Wochenschr ; 137(7-8): 161-75, 1987 Apr 30.
Artículo en Alemán | MEDLINE | ID: mdl-3300046

RESUMEN

Table 5 gives an overview as to the timing and indication for diagnostic methods and procedures in cerebro-vascular diseases. Anamnesis and clinical aspects have still leading position. After that, computer-tomography stands first in the diagnostic line, followed by angiography, indicated in the acute phase only in progressive stroke. More often it is used during rehabilitation period for indication towards extra-intracranial anastomosis. Sonography gives informations specially in the extracranial stenoses by duplex sonography. The EEG is still necessary in the early stage and for follow-ups. Cerebro spinal fluid analysis, intern medicine (mainly cardiology) examinations, give extra information and should not be skipped. Psychological exams and intracranial bloodflow-studies are used during rehabilitation. Digital angiography, with the possibility of postprocessing, is in comparison to conventional angiography, less invasive. Nuclear-magnetic-resonance with its fast development is taking now place in the clinical field. Cerebro-vascular patients should be treated in specialized centers where beside the equipment, an experienced team is available, which has required its knowledge on a high number of cases and where the cooperation between the different fields of conservative (intern and neurology) radiology and surgery is guaranteed. This paper however has tried to show the up-to-date-guidelines to the other medical specialties that handle cerebrovascular patients.


Asunto(s)
Trastornos Cerebrovasculares/diagnóstico , Isquemia Encefálica/diagnóstico , Angiografía Cerebral , Infarto Cerebral/diagnóstico , Ecoencefalografía , Electroencefalografía , Humanos , Ataque Isquémico Transitorio/diagnóstico , Trastornos Neurocognitivos/diagnóstico , Hemorragia Subaracnoidea/diagnóstico , Técnica de Sustracción , Tomografía Computarizada por Rayos X
14.
Plant Cell Rep ; 9(10): 535-8, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24220706

RESUMEN

Shoot tips and epicotyl-segments of Vicia narbonensis were co-cultivated with Agrobacterium tumefaciens strain C58C1 pGV 3850 HPT, carrying a plasmid coding for hygromycin-phosphotransferase. On callus-induction medium containing 60 mg/l hygromycin for selection, approximately 18% of the explants produced hygromycin-resistant callus. After transfer to regeneration-medium these calluses produced hygromycin-resistant and nopaline-positive somatic embryos which could be regenerated to plantlets. The integration of the T-DNA into the plant genome was confirmed by Southern analysis.

15.
Phys Rev Lett ; 87(23): 236101, 2001 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-11736460

RESUMEN

By means of kinetic Monte Carlo simulations of the self-organized growth of quantum dots in strained semiconductor systems we resolve the seemingly contradictory features of kinetic versus thermodynamic behavior, e.g., with respect to the temperature dependence of the average dot size and their dispersion. We show that the size distribution immediately after deposition is kinetically controlled, with smaller islands for lower temperatures and larger islands for higher temperatures. For longer simulation times the kinetics leads to equilibration, and a crossover effect between the size distributions occurs, which is in good agreement with the predictions of thermodynamics.

16.
Nucl Med (Stuttg) ; 15(1): 32-5, 1976 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1257046

RESUMEN

25 patients with known cerebral disease (either CVA's or primary or secondary tumours) diagnosed by clinical and angiographic criteria were submitted to a double isotope imaging technique using 99mTcO4- and 99mTc-EHDP. The different biological behaviour of these radiopharmaceuticals has provided specific and differential diagnosis between vascular and neoplastic disease of the brain. 99mTc-EHDP is shown to be the tracer of choice for the imaging of CVA's and 99mTcO4- is confirmed as the tracer of choice for the imaging of primary or secondary tumours in the brain.


Asunto(s)
Encefalopatías/diagnóstico , Cintigrafía/métodos , Adulto , Anciano , Neoplasias Encefálicas/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Organofosfonatos , Tecnecio
17.
Theor Appl Genet ; 81(6): 819-24, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24221447

RESUMEN

Methods are described whereby hybridization of mitochondrial (mt) DNA with different DNA probes can definitely distinguish male-fertile and and male-sterile (cms) cytoplasms of sugar beet Beta vulgaris L. We have developed two types of miniassays. (1) Comparative methods requiring the isolation and restriction of total cellular DNA, hybridization with cloned mtDNA fragments from either fertile or male-sterile cytoplasms, and comparison of the hybridization patterns to the fertile-and sterile-specific patterns of mtDNA of sugar beet for the given mtDNA probe. For these analyses, we routinely used 1 g of plant material to determine the type of cytoplasm. (2) Noncomparative ("plus-minus") methods requiring neither the isolation of pure DNA nor restriction, electrophoresis, or Southern blotting. Instead, alkaline-SDS plant extracts from as little as 50 mg of plant material were dot-blotted and hybridized with fertile-specific (mitochondrial minicircular DNA) and/or cms-specific probes (consisting of a 2.3-kb mtDNA sequence exclusively occurring in the cms cytoplasm). The assays are simple to perform, give definitive results, are nonde-structive to the plants, and may be used in mass screening of sugar beet populations for hybrid production or in in vitro culture processes.

18.
Plant Cell Rep ; 12(7-8): 390-4, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-24197338

RESUMEN

We developed a highly efficient transformation protocol for the PEG-mediated direct transfer of plasmid DNA into protoplasts of haploid Datura innoxia. Vectors harbouring a neomycin phosphotransferase II gene or a hygromycin B phosphotransferase gene under the control of different promoters were used in the transformation experiments. Various amounts of plasmid DNA were applied without any carrier DNA to show the direct influence of the plasmid DNA concentration on the transformation efficiency. Approximately 95% of the selected calli were regenerated to plants; 20% of them remained haploid. Total DNA of different transgenic plants was analysed with regard to the integration pattern of the plasmid DNA. Plants carrying only one or two copies of the vector DNA were observed as well as individuals with multi-copy integration (up to ten or more copies).

19.
Theor Appl Genet ; 83(6-7): 691-4, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24202742

RESUMEN

Oligonucleotides hybridizing to simple repetitive DNA patterns are highly informative as probes for DNA fingerprinting in all investigated animal species, including man. Here we demonstrate the applicability of this technique in higher plants. The oligonucleotide probes (GTG)5 and (GATA)4 were used to investigate the differences in DNA fingerprint patterns of the following angiosperm species: Triticum aestivum, Secale cereale, Hordeum vulgare, Beta vulgaris, Petunia hybrida, Brassica oleracea, and Nicotiana tabacum. Two species, Hordeum vulgare as a monocot and Beta vulgaris as a dicot, were analyzed in more detail. Their genomes differ considerably in both amount and organization of the simple repetitive sequences (GATA)n, (GACA)n, (GTG)n, and (CT)n due to the evolutionary distance of these two species. Furthermore, several lines and cultivars of Beta vulgaris and Hordeum vulgare can clearly be distinguished on the basis of their highly polymorphic patterns of these repetitive sequences.

20.
Br J Dermatol ; 145(6): 938-43, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11899147

RESUMEN

BACKGROUND: After exposure, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is excreted via the faeces, breast milk and epidermal lipids. OBJECTIVES: To determine to what extent TCDD is eliminated via the skin and to evaluate whethe cutaneous elimination can be accelerated by the application of petrolatum. METHODS: In two patients severely intoxicated with TCDD, material obtained from the skin surface and, in one patient, cerumen and the content of epithelial cysts, was analysed for TCDD. RESULTS: The TCDD concentration in the initial blood sample taken was 144 000 pg g(-1) blood fa in patient 1, and 26 000 pg g(-1) blood fat in patient 2. Six months later, when the skin tests were performed, the blood TCDD levels had decreased to 80 900 and 16 100 pg g(-1) blood fat, respectively. In the two samples of pooled cyst contents from patient 1, TCDD levels of 34 400 an 18 600 pg g(-1) fat were found. A cerumen sample contained TCDD at 20 500 pg g(-1) fat. In the material collected from the skin surface we observed a linear increase of the amount of TCD measured per test field with time, indicating a continuous elimination of TCDD via the skin. Th daily amount of TCDD eliminated via the skin was 1.51 pg cm(-2) in patient 1 and 0.57 pg cm(-2) in patient 2. Application of petrolatum led to a twofold increase in the amount of TCDD measured in patient 1, but had no significant effect in patient 2. CONCLUSIONS: In our patients, elimination of TCDD via the skin, most probably through desquamating scales, represented 1-2% of the overall daily TCDD elimination rate, with regard to the body surface and when calculated on the basis of the half-life of TCDD at the time of the skin test. If a more typical overall elimination half-life of 7 years is used as the basis for the calculatio the skin would account for 9% (patient 1) and 15% (patient 2) of the overall elimination. Although we observed an increase in TCDD in material derived from the skin surface of up to 100% after application of petrolatum in patient 1, such an approach appears not to be a feasible means to increase elimination. Owing to the small amount of TCDD measured in skin-surface material, as well as in the cyst contents and cerumen obtained from one patient, contamination of the environment and other persons appears highly unlikely.


Asunto(s)
Acné Vulgar/inducido químicamente , Contaminantes Ambientales/farmacocinética , Dibenzodioxinas Policloradas/farmacocinética , Piel/metabolismo , Teratógenos/farmacocinética , Acné Vulgar/metabolismo , Adulto , Cerumen/metabolismo , Emolientes/farmacología , Contaminantes Ambientales/sangre , Contaminantes Ambientales/envenenamiento , Femenino , Estudios de Seguimiento , Humanos , Inactivación Metabólica , Vaselina/farmacología , Dibenzodioxinas Policloradas/sangre , Dibenzodioxinas Policloradas/envenenamiento , Piel/efectos de los fármacos
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