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1.
Data Brief ; 24: 103921, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31061862

RESUMO

The data presented here is complementary to the publication entitled "High temperature, low neutron cross-section high-entropy alloys in the Nb-Ti-V-Zr system" [1]. A homogenization methodology with slower cooling rate (∼2 °C/min) was performed. X-ray diffraction and scanning electron microscopy (backscattered electron and energy dispersive spectroscopy) data pertaining to annealed high-entropy alloy composition NbTiVZr is presented.

2.
J Exp Mar Biol Ecol ; 260(2): 155-167, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11358576

RESUMO

Cryptocotyle lingua (Creplin) is a digenean trematode parasite of the littoral prosobranch gastropod Littorina littorea (L.). The literature suggests the snails become infected by grazing guano of the final host, the herring gull, Larus argentatus Pontoppidan. The parasite emerges from the snail as free-swimming cercariae. Interactions between the snail and the parasite at cellular and life-history levels are well established, but little is known of the influences the interaction has on the behaviour and the ecology of the snail. We tested the response of the snail to encounters with cercariae, examined the longevity of the guano on-shore and tested the responses of the snail to encounters with guano. Over half the L. littorea tested were able to detect both cercariae and a filtered homogenate of cercariae in conspecific mucus trails, approximately one-third of animals refusing to cross the treatments. Chemoreception by the mouth or foot is considered the most likely means of detection. Guano samples (mean weight 3.22 g) naturally deposited at approximately mid-tide level were completely washed away by one tidal inundation. We consider this period too brief to allow for ingestion of eggs in guano by the snail. Further, snails would not cross guano placed in conspecific trails. Most snails would not cross guano diluted by 10(3)x(10 mg ml(-1)) and some snails could still detect guano diluted by 10(6)x(10 &mgr;g ml(-1)), though all were prepared to cross it. Detection of guano is again believed to be by chemoreception by the mouth or foot. These results are discussed in terms of the mating and aggregating behaviour of L. littorea. Ingestion of the parasite by L. littorea is likely to take place once the guano has washed away as the eggs are negatively buoyant in seawater and may adhere to rock (biofilm) or algal fronds which may be grazed by the snail.

3.
NMR Biomed ; 12(1): 39-44, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10195328

RESUMO

The quantitation of in vivo 1H MR spectroscopy and dynamic contrast enhanced MR imaging is described for patients with histologically confirmed prostate adenocarcinoma and benign prostatic hypertrophy (BPH). Results are presented which suggest that combined use of these techniques may be helpful in improving the characterization of prostate pathologies and ultimately increase the staging accuracy of magnetic resonance.


Assuntos
Imageamento por Ressonância Magnética/métodos , Ressonância Magnética Nuclear Biomolecular/métodos , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Idoso , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Magn Reson Imaging ; 9(2): 311-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10077030

RESUMO

One of the major factors limiting the staging accuracy of conventional magnetic resonance imaging (MRI) for prostatic carcinoma, is the similarity in signal intensity between tumor and coexisting benign prostatic hyperplasia (BPH). As neovascularity is an independent indicator of pathological state, dynamic contrast-enhanced MRI may yield additional information. This study correlates the histopathological findings from 12 radical prostatectomy patients on a region-by-region basis, with pharmacokinetic modeling of dynamic contrast-enhanced (0.2 mmol dimeglumine gadopentetate/kg), fast multiplanar spoilt gradient-recalled echo images, using a two-compartment simplex minimization technique. Quantitative analysis demonstrated differences in the amplitude of the initial contrast upslope and contrast exchange rate between tumor and fibromuscular BPH (P<0.03 and P<0.03, respectively) and for the contrast exchange rate between tumor and fibroglandular BPH (P<0.04), providing improved delineation of intraprostatic tumor extent compared with conventional imaging techniques.


Assuntos
Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , Idoso , Meios de Contraste , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Magn Reson Imaging ; 8(4): 994-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9702904

RESUMO

A simple method is described that corrects for the intensity inhomogeneity experienced when using endorectal surface coils in prostate imaging. The method uses a series of proton-density-weighted images, which are acquired to demonstrate the sensitivity profile of the coil and used to correct T2-weighted images acquired in the same plane. The results demonstrate improved image uniformity and visualization of prostatic anatomy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Idoso , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico
6.
Magn Reson Imaging ; 15(10): 1177-86, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9408138

RESUMO

We have previously reported a striking correlation between water T2 relaxation time and citrate concentration in the normal prostate (Liney G.P.; Lowry M.; Turnbull L.W.; Manton D.J.; Knowles A.J.; Blackband S.J.; Horsman A. Proton MR T2 maps correlate with the citrate concentration in the prostate. NMR Biomed. 9:59-64; 1996). In this study we present data from similar studies of the pathologic gland. The findings support the hypothesis that measurement of both citrate concentration and water T2 relaxation time in vivo may aid the differentiation of prostatic carcinoma from benign disease and normal tissue.


Assuntos
Adenocarcinoma/metabolismo , Água Corporal/metabolismo , Ácido Cítrico/metabolismo , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Neoplasias da Próstata/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Biópsia , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/metabolismo , Prostatectomia , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
7.
J Magn Reson Imaging ; 6(4): 603-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8835953

RESUMO

The accuracy of water T2 maps generated from a fast spin-echo (FSE) sequence was compared with data obtained by conventional single and multi-echo spin-echo pulse sequences using a commercial gel phantom. Spatially localized stimulated echo acquisition mode (STEAM) proton spectroscopy was also used to confirm the reported water T2 values of the gels contained in the phantom. The FSE sequence was shown to be superior in accuracy to both the single and multi-echo spin echo sequences and comparable to STEAM, producing results that were within 10% of known values. The effectiveness of the FSE sequence was further demonstrated by generating T2 maps of the normal and diseased prostate in clinically acceptable imaging times, resulting in comparable T2 values to those obtained using STEAM. Accurate quantitative T2 maps can be produced with the FSE sequence.


Assuntos
Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Próstata/anatomia & histologia , Carcinoma/patologia , Géis , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Imagens de Fantasmas , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Água
8.
NMR Biomed ; 9(2): 59-64, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8887369

RESUMO

A significant correlation between water T2 relaxation time and citrate concentration in the normal prostate is demonstrated using spatially localized spectroscopy and water T2 maps. These data imply that MR images may be used to infer the concentration of citrate at high spatial resolution. Preliminary results in patients demonstrate that this relationship is maintained in benign prostatic hyperplasia (BPH) and prostatic carcinoma. The determination of citrate concentration and water T2 may aid the differentiation of prostate carcinoma from BPH and normal tissue.


Assuntos
Citratos/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Próstata/anatomia & histologia , Próstata/metabolismo , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Água/metabolismo
9.
Radiology ; 198(3): 899-902, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8628890

RESUMO

Peripheral magnetic resonance (MR) angiography was performed in eight volunteers, with a temperature-controlled water blanket. After warming of the right foot, unobserved vessels became conspicuous in all patients: Average increase in signal intensity was nearly twofold in the major artery and vein depicted. A similar improvement was observed in an examination in one patient with diabetes. Peripheral MR angiography performed after warming provided additional diagnostic information.


Assuntos
Temperatura Corporal , Pé/irrigação sanguínea , Angiografia por Ressonância Magnética , Adulto , Pé Diabético/diagnóstico , Pé Diabético/fisiopatologia , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Valores de Referência
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