1,027 research outputs found
Tumor cerebral: incidência, diagnóstico e tratamento
Relatório de estágio de licenciatura, Bioquímica, Faculdade de Ciências e Tecnologia da Universidade do Algarve, 2010O tumor cerebral é um tumor raro. A sua relevância incide no facto de pertencer
aos tipos de tumores para os quais não existe cura, que provocam défices profundos
nos doentes e cujos sintomas são muitas vezes negligenciados.
Este estudo engloba doentes com diagnóstico de tumor cerebral maligno,
internados no período de 1 de Junho de 2008 a 30 de Julho de 2010, no Hospital de
Faro E.P.E..
Foram contabilizados 84 processos clínicos, porém apenas 52 destes puderam
ser analisados. Destes 52 processos, 56% pertenciam ao sexo masculino sendo que a
maior frequência foi encontrada na faixa etária dos 71 aos 75 anos. Apenas metade
dos doentes realizou biopsia e o tipo de tumor cerebral maligno mais frequente foi o
glioblastoma, contando com 32 diagnósticos, sendo que 81% da totalidade dos casos
são tumores gliais. Somente 29% dos doentes ainda se encontram vivos até à data e o
tempo de sobrevivência foi de apenas 1 mês para 24% dos doentes falecidos após
diagnóstico de tumor cerebral maligno. Do total de diagnósticos analisados somente
realizaram cirurgia 30 doentes, 18 fizeram radioterapia e 13 foram propostos a
quimioterapia.
Cefaleias, hemiparesia, convulsões, confusão, astenia, febre, afasia, paralisia
facial, prostração, desorientação e vómitos, foram os sintomas constatados mais
frequentemente.The brain tumor is a rare tumor. Its importance relies in the fact that it belongs
to the tumor types for which there’s no cure and that causes profound deficits in
patients, which symptoms are often, overlooked.
This study includes patients whose malignant brain tumor diagnosis, was carried
out from June 1st 2008 to July 30th 2010, in Hospital de Faro E.P.E..
84 clinical cases were reported, but only 52 of these could be analysed. From
these 52 cases, 56% were male and the highest frequency was found in the age range
of 71 to 75 years. Only half of the patients performed biopsy and the malignant brain
tumor glioblastoma was the most frequent, with 32 diagnoses, where 81% of all cases
are glial tumors. Only 29% of patients are still alive so far and the survival time was
only 1 month to 24% of deceased patients after diagnosis. In the total of diagnoses
examined only 30 patients underwent surgery, 18 had radiotherapy and 13 were
proposed to chemotherapy.
Headache, hemiparesis, seizures, confusion, weakness, fever, aphasia, facial
paralysis, prostration, disorientation and vomiting were the most observed symptoms
The optical-ultraviolet continuum of Seyfert 2 galaxies
This paper aims to understand the continuum of Seyfert 2 galaxies. By fitting
the single galaxies in the sample of Heckman et al. (1995) with composite
models (shock+ photoionization from the active center), we show that five main
components characterize the SED of the continuum. Shocks play an important role
since they produce a high temperature zone where soft X-rays are emitted.
We show that in the optical-UV range, the slope of the NLR emission
reproduces the observed values, and may be the main component of the
featureless continuum. The presence of star forming regions cannot be excluded
in the circumnuclear region of various Seyfert galaxies. An attempt is made to
find their fingerprints in the observed AGN spectra. Finally, it is
demonstrated that multi-cloud models are necessary to interpret the spectra of
single objects, even in the global investigation of a sample of galaxies.Comment: 26 pages, LaTeX (including 5 Tables) + 17 PostScript figures. To
appear in "The Astrophysical Journal
C, N, O Abundances in the Most Metal-Poor Damped Lyman alpha Systems
This study focuses on some of the most metal-poor damped Lyman alpha
absorbers known in the spectra of high redshift QSOs, using new and archival
observations obtained with UV-sensitive echelle spectrographs on the Keck and
VLT telescopes. The weakness and simple velocity structure of the absorption
lines in these systems allows us to measure the abundances of several elements,
and in particular those of C, N, and O, a group that is difficult to study in
DLAs of more typical metallicities. We find that when the oxygen abundance is
less than about 1/100 of solar, the C/O ratio in high redshift DLAs and
sub-DLAs matches that of halo stars of similar metallicity and shows higher
values than expected from galactic chemical evolution models based on
conventional stellar yields. Furthermore, there are indications that at these
low metallicities the N/O ratio may also be above simple expectations and may
exhibit a minimum value, as proposed by Centurion and her collaborators in
2003. Both results can be interpreted as evidence for enhanced production of C
and N by massive stars in the first few episodes of star formation, in our
Galaxy and in the distant proto-galaxies seen as QSO absorbers. The higher
stellar yields implied may have an origin in stellar rotation which promotes
mixing in the stars' interiors, as considered in some recent model
calculations. We briefly discuss the relevance of these results to current
ideas on the origin of metals in the intergalactic medium and the universality
of the stellar initial mass function.Comment: 17 pages, 9 Figures, Accepted for publication in Monthly Notices of
the Royal Astronomical Societ
Nutrição e adubação: conceitos e aplicações na formação de mudas de pimenta longa.
bitstream/item/61763/1/Oriental-Doc13.pd
Teores de N, P, K, Ca, Mg e S em gravioleiras cultivadas em solução nutritiva com omissão de macronutrientes.
Publicado também: FRAZÃO, D. A. C.; HOMMA, A. K. O; VIÉGAS, I. de J. M. (Ed.). Contribuição ao desenvolvimento da fruticultura na Amazônia. Belém, PA: Embrapa Amazônia Oriental, 2006. p. 503-508
Heavy element abundances in blue compact galaxies
We present high-quality ground-based spectroscopic observations of 54
supergiant H II regions in 50 low-metallicity blue compact galaxies with oxygen
abundances 12 + log O/H between 7.1 and 8.3. We use the data to determine
abundances for the elements N, O, Ne, S, Ar and Fe. We also analyze Hubble
Space Telescope (HST) Faint Object Spectrograph archival spectra of 10
supergiant H II regions to derive C and Si abundances in a subsample of 7 BCGs.
The main result of the present study is that none of the heavy
element-to-oxygen abundance ratios studied here (C/O, N/O, Ne/O, Si/O, S/O,
Ar/O, Fe/O) depend on oxygen abundance for BCGs with 12 + log O/H < 7.6 (Z <
Zsun/20). This constancy implies that all these heavy elements have a primary
origin and are produced by the same massive (M > 10Msun) stars responsible for
O production. The dispersion of the C/O and N/O ratios in these galaxies is
found to be remarkably small, being only +/-0.03 dex and +/-0.02 dex
respectively. This very small dispersion is strong evidence against any
time-delayed production of C and primary N in the lowest-metallicity BCGs
(secondary N production is negligible at these low metallicities). The absence
of a time-delayed production of C and N is consistent with the scenario that
galaxies with 12 + log O/H < 7.6 are undergoing now their first burst of star
formation, and that they are therefore young, with ages not exceeding 40 Myr.
If very low metallicities BCGs are indeed young, this would argue against the
commonly held belief that C and N are produced by intermediate-mass (3Msun < M
< 9Msun) stars at very low metallicities, as these stars would not have yet
completed their evolution in these lowest metallicity galaxies.Comment: 37 pages, 5 EPS figures, to appear in ApJ, February 199
Doses de nitrogênio, fósforo e potássio no desenvolvimento da seringueira (Hevea brasiliensis Muell. Arg.) em Latossolo Amarelo textura media - Tracuateua, PA.
Experimento foi conduzido, durante oito anos, no município de Bragança, na localidade de Tracuateua, com o objetivo de avaliar a influencia da adubação nitrogenada (sulfato de amônio), fosfatada (superfosfato triplo) e potássica (cloreto de potássio) no desenvolvimento da seringueira (Fx 3899). O delineamento foi de blocos ao acaso com duas repetições em arranjo fatorial 3 x 3 x 2 para NPK, com lastro uniforme de magnésio. O nitrogênio não proporcionou efeito positivo na altura das plantas e no desenvolvimento do tronco, enquanto que potássio e fosforo apresentaram respostas benéficas significativas
Efeitos da omissão de macro e micronutrientes no desenvolvimento de mudas de cupuaçuzeiro.
Publicado também: FRAZÃO, D. A. C.; HOMMA, A. K. O; VIÉGAS, I. de J. M. (Ed.). Contribuição ao desenvolvimento da fruticultura na Amazônia. Belém, PA: Embrapa Amazônia Oriental, 2006. p. 445-452
Sintomas visuais de deficiências de macronutrientes em plantas de curauá variedade roxo (Ananas erectifolius).
FERTBIO 2006
An Imaging and Spectroscopic Study of the z=3.38639 Damped Lyman Alpha System in Q0201+1120: Clues to Star Formation Rate at High Redshift
We present the results of a series of imaging and spectroscopic observations
aimed at identifying and studying the galaxy responsible for the z = 3.38639
damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part
of a concentration of matter which includes at least four galaxies (probably
many more) over linear comoving dimensions, greater than 5h^-1Mpc. The absorber
may be a 0.7 L* galaxy at an impact parameter of 15 h^-1 kpc, but follow-up
spectroscopy is still required for positive identification. The gas is
turbulent, with many absorption components distributed over approximately 270
km/s and a large spin temperature, T_s greater than 4000K. The metallicity is
relatively high for this redshift, Z(DLA) approximately 1/20 Z(solar). From
consideration of the relative ratios of elements which have different
nucleosynthetic timescales, it would appear that the last major episode of star
formation in this DLA occurred at z greater than 4.3, more than approximately
500 Myr prior to the time when we observe it.Comment: Accepted for publication in Ap
- …