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1.
BMC Cancer ; 22(1): 286, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35300636

RESUMO

BACKGROUND: MDT discussion is the gold standard for cancer care in the UK. With the incidence of cancer on the rise, demand for MDT discussion is increasing. The need for efficiency, whilst maintaining high standards, is therefore clear. Paper-based MDT quality assessment tools and discussion checklists may represent a practical method of monitoring and improving MDT practice. This reviews aims to describe and appraise these tools, as well as consider their value to quality improvement. METHODS: Medline, EMBASE and PsycInfo were searched using pre-defined terms. The PRISMA model was followed throughout. Studies were included if they described the development of a relevant tool, or if an element of the methodology further informed tool quality assessment. To investigate efficacy, studies using a tool as a method of quality improvement in MDT practice were also included. Study quality was appraised using the COSMIN risk of bias checklist or the Newcastle-Ottawa scale, depending on study type. RESULTS: The search returned 7930 results. 18 studies were included. In total 7 tools were identified. Overall, methodological quality in tool development was adequate to very good for assessed aspects of validity and reliability. Clinician feedback was positive. In one study, the introduction of a discussion checklist improved MDT ability to reach a decision from 82.2 to 92.7%. Improvement was also noted in the quality of information presented and the quality of teamwork. CONCLUSIONS: Several tools for assessment and guidance of MDTs are available. Although limited, current evidence indicates sufficient rigour in their development and their potential for quality improvement. TRIAL REGISTRATION: PROSPERO ID: CRD42021234326 .


Assuntos
Lista de Checagem , Comunicação Interdisciplinar , Neoplasias/terapia , Equipe de Assistência ao Paciente , Qualidade da Assistência à Saúde/normas , Humanos , Oncologia/métodos , Reprodutibilidade dos Testes
2.
Proc Natl Acad Sci U S A ; 114(33): E6759-E6766, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28760968

RESUMO

The continental shelves are the most biologically dynamic regions of the ocean, and they are extensive worldwide, especially in the western North Pacific. Their area has varied dramatically over the glacial/interglacial cycles of the last million years, but the effects of this variation on ocean biological and chemical processes remain poorly understood. Conversion of nitrate to N2 by denitrification in sediments accounts for half or more of the removal of biologically available nitrogen ("fixed N") from the ocean. The emergence of continental shelves during ice ages and their flooding during interglacials have been hypothesized to drive changes in sedimentary denitrification. Denitrification leads to the occurrence of phosphorus-bearing, N-depleted surface waters, which encourages N2 fixation, the dominant N input to the ocean. An 860,000-y record of foraminifera shell-bound N isotopes from the South China Sea indicates that N2 fixation covaried with sea level. The N2 fixation changes are best explained as a response to changes in regional excess phosphorus supply due to sea level-driven variations in shallow sediment denitrification associated with the cyclic drowning and emergence of the continental shelves. This hypothesis is consistent with a glacial ocean that hosted globally lower rates of fixed N input and loss and a longer residence time for oceanic fixed N-a "sluggish" ocean N budget during ice ages. In addition, this work provides a clear sign of sea level-driven glacial/interglacial oscillations in biogeochemical fluxes at and near the ocean margins, with implications for coastal organisms and ecosystems.

3.
Science ; 356(6339): 749-752, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28522534

RESUMO

With the rapid rise in pollution-associated nitrogen inputs to the western Pacific, it has been suggested that even the open ocean has been affected. In a coral core from Dongsha Atoll, a remote coral reef ecosystem, we observe a decline in the 15N/14N of coral skeleton-bound organic matter, which signals increased deposition of anthropogenic atmospheric N on the open ocean and its incorporation into plankton and, in turn, the atoll corals. The first clear change occurred just before 2000 CE, decades later than predicted by other work. The amplitude of change suggests that, by 2010, anthropogenic atmospheric N deposition represented 20 ± 5% of the annual N input to the surface ocean in this region, which appears to be at the lower end of other estimates.


Assuntos
Atmosfera/química , Recifes de Corais , Ecossistema , Nitrogênio/metabolismo , Água do Mar/química , China , História do Século XX , História do Século XXI , Atividades Humanas/história , Nitrogênio/análise , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Oceano Pacífico , Plâncton/química , Plâncton/metabolismo , Fatores de Tempo
4.
Sci Rep ; 7: 44586, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28333165

RESUMO

A 2 °C increase in global temperature above pre-industrial levels is considered a reasonable target for avoiding the most devastating impacts of anthropogenic climate change. In June 2015, sea surface temperature (SST) of the South China Sea (SCS) increased by 2 °C in response to the developing Pacific El Niño. On its own, this moderate, short-lived warming was unlikely to cause widespread damage to coral reefs in the region, and the coral reef "Bleaching Alert" alarm was not raised. However, on Dongsha Atoll, in the northern SCS, unusually weak winds created low-flow conditions that amplified the 2 °C basin-scale anomaly. Water temperatures on the reef flat, normally indistinguishable from open-ocean SST, exceeded 6 °C above normal summertime levels. Mass coral bleaching quickly ensued, killing 40% of the resident coral community in an event unprecedented in at least the past 40 years. Our findings highlight the risks of 2 °C ocean warming to coral reef ecosystems when global and local processes align to drive intense heating, with devastating consequences.


Assuntos
Antozoários/fisiologia , Recifes de Corais , Temperatura Alta , Modelos Estatísticos , Animais , China , Clima , Ecossistema , El Niño Oscilação Sul , Oceano Pacífico , Água do Mar , Estresse Fisiológico
5.
Methods Protoc ; 1(1)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31164551

RESUMO

A single solution protocol has been widely used for the fluorimetric determination of H2O2 in natural waters by its bleaching of the fluorescing scopoletin in the presence of the enzyme horseradish peroxidase (HRP). In this protocol, the reaction between scopoletin and H2O2 in the sample and the subsequent internal additions, and the measurements of the fluorescence are all carried out at a single pH in a fluorometer cell. It is found that this protocol is prone to four sources of possible error. The variability in the reaction stoichiometry between scopoletin and H2O2 in the presence of varying amounts of excess scopoletin, the effect of pH on the rate of reaction between scopoletin and H2O2, the photobleaching of scopoletin, and the de-activation of HRP. These possible sources of error can be circumvented in a two-stage protocol in which the reaction between H2O2 and scopoletin is carried out immediately upon sampling at a pH of 7, and the measurement of the fluorescence is carried out later on at a pH of 9. It should be the protocol of choice. Furthermore, in the two-stage protocol, after the initial reaction between H2O2 and scopoletin, the sample may be stored at room temperature for six days and at 4 °C for at least a month before its fluorescence is measured. This option can significantly reduce the logistics in the field.

6.
J Zoo Wildl Med ; 35(3): 347-55, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15526890

RESUMO

Iodine in the form of iodide is required for synthesis of tri-iodothyronine and thyroxine in fish. Iodine chemical speciation in aliquots of raw artificial seawater mix was measured before, during, and after exposure for fixed time periods to air only and to concentrations of ozone required to achieve oxidation-reduction potentials typical of a protein skimmer (400 mV) and an ozone contact chamber (800 mV). Chemical species of iodine were also measured in tank water from a large, recirculating, ozonated aquarium system that has a low-grade incidence of thyroid lesions (e.g., thyroiditis, hyperplasia, adenoma, and adenocarcinoma) in its fish. With increasing exposure to ozone, concentrations of iodide and dissolved organic iodine (DOI) decreased, whereas iodate levels increased. As a result of exposure to 400 mV, iodide concentration dropped to less than half the amount found in raw artificial seawater mix. After exposure to 800 mV, initial iodide levels decreased by 67%, and DOI became undetectable, whereas iodate concentration increased by 155%, with no remarkable change in total iodine concentration. These results indicate ozone-induced conversions from iodide to iodate, and DOI to iodide or iodate (or both). Iodide and DOI were not detectable in the aquarium system's water samples. Ozonation of artificial seawater may alter the relative concentrations of iodine species in a closed tank system, so that iodide supplementation of the diet or tank water of captive teleosts and elasmobranchs living in ozonated seawater is advisable.


Assuntos
Peixes/metabolismo , Iodo/química , Ozônio/química , Água do Mar/química , Animais , Aquicultura , Iodatos/análise , Iodatos/química , Iodetos/análise , Iodetos/química , Iodo/análise , Oxirredução
7.
Appl Opt ; 40(13): 2138-47, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18357221

RESUMO

The new optical effect of diffractive multifocal focusing of radiation, predicted earlier by theory, on a bicomponent diffraction system with small Fresnel numbers that consists of two plane screens with circular apertures on given optical axes, is confirmed experimentally. It is shown that the diffraction picture in the focal planes of such a system represents the circular nonlocal bands of the Fresnel zones with a bright narrow peak at the center, whose intensity in the experiment can exceed by six to ten times the value of the incident plane-wave intensity. Experimentally it is established that the diffractive multifocal focusing of radiation on real screens with axial circular apertures, whose diameters exceed the radiation wavelength, is insensitive to the rough external conditions: thickness of the screens, irregularities of the edges and nonideal form of the apertures, heterogeneity of the initial distribution of the incident-wave intensity, and changes in the medium of the wave propagation.

8.
Opt Lett ; 25(18): 1364-6, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18066218

RESUMO

An inversionless gain of anti-Stokes radiation above the oscillation threshold in an optically dense far-from-degenerate double- ? Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes are illustrated with numerical simulations applied to sodium dimer vapor. Optical switching from absorption to gain via transparency controlled by a small variation of the medium and of the driving radiation parameters, which are at a level of less than one photon per molecule, is shown.

9.
Appl Opt ; 39(16): 2545-50, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18345169

RESUMO

It is shown for the first time, to our knowledge, that when a plane wave illuminates a certain type of bicomponent optical system, consisting of two plane screens with circular apertures on a given optical axis, a multifocal diffractive focusing effect can appear. Here the diffraction picture in the focal planes represents the circular nonlocal bands of the Fresnel zones with a bright narrow peak at the center, whose intensity can exceed by 6-10 times the value of the incident-wave intensity. The detected optical effect is observed across a wide range of wavelengths, lambda = 0.4-10(3) microm, and ratios of the aperture diameters d(1) >or= 2d(2) = 25-1000 lambda, and it is also insensitive to changes in the medium of the wave propagation. For the large diameters of input holes, d(1) = 2d(2) > 100 lambda, or for wavelengths in the radio-frequency region of the spectrum, the bicomponent diffraction system acts as a long-focus lens with a high-intensity Gaussian distribution of radiation, at times exceeding the initial intensity, persisting at large distances (z = 1-100 cm) from the diffraction system.

10.
J Small Anim Pract ; 37(10): 480-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8912242

RESUMO

Partial cystectomy was performed in 11 dogs with bladder neoplasia (10 with transitional cell carcinoma and one with rhabdomyosarcoma). Between 40 and 70 per cent of the bladder was excised during the partial cystectomies. In eight dogs, all the grossly visible tumour was excised but on histopathological examination of the excised tissue, neoplastic tissue was found to extend to the surgical margins in four of these dogs. A ureteral stoma was excised with the tumour in four dogs necessitating ureteral reimplantation; one dog had both ureteral stomas excised and bilateral ureteral reimplantation. The bladder incision dehisced in two dogs, necessitating a second surgery. Six dogs were pollakiuric after surgery. Pollakiuria resolved within two months in four dogs and persisted in two dogs. None was incontinent. Local tumour recurrence was suspected in nine dogs based on imaging studies and confirmed in five dogs during post mortem examination. Five dogs were euthanased two to seven months after surgery. Six dogs survived at least one year, two of these dogs remain alive at 17 and 27 months after surgery. It is concluded that partial cystectomy may provide local control of bladder neoplasia.


Assuntos
Carcinoma de Células de Transição/veterinária , Cistectomia/veterinária , Doenças do Cão/cirurgia , Rabdomiossarcoma/veterinária , Resultado do Tratamento , Neoplasias da Bexiga Urinária/veterinária , Animais , Carcinoma de Células de Transição/fisiopatologia , Carcinoma de Células de Transição/cirurgia , Cistectomia/métodos , Doenças do Cão/epidemiologia , Doenças do Cão/fisiopatologia , Cães , Feminino , Masculino , Rabdomiossarcoma/fisiopatologia , Rabdomiossarcoma/cirurgia , Neoplasias da Bexiga Urinária/fisiopatologia , Neoplasias da Bexiga Urinária/cirurgia
11.
Otolaryngol Head Neck Surg ; 111(4): 509-12, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7936687

RESUMO

The decision to transfuse patients after major head and neck reconstructive surgery has been influenced by the dictum that a hematocrit level of 30% or more is necessary for the survival of surgical flaps. Pedicled myocutaneous flaps are among the most frequently used methods of reconstruction after major head and neck oncologic surgery. No studies have addressed the survival of myocutaneous pedicled flaps in anemic animals. In this study survival of latissimus dorsi myocutaneous flaps in pigs was evaluated in anemic and control groups. A total of 26 pigs were randomly divided into two groups. The pigs in the anemic group were exsanguinated to normovolemic anemia (average hematocrit, 19%), followed by elevation of a latissimus dorsi myocutaneous flap. In the control group the same operation was performed without exsanguination. All other variables were kept constant. The flap survival was judged on postoperative days 3, 7, and 14 by two evaluators. Ten pigs from each group were found to have 100% flap survival on post-operative day 14. There was no significant difference in mean flap survival rates between two groups for postoperative days 3, 7, and 14. It is concluded that normovolemic anemia does not adversely affect the survival of the myocutaneous flaps. This finding may save unnecessary transfusions in postoperative patients.


Assuntos
Anemia/fisiopatologia , Retalhos Cirúrgicos/fisiologia , Cicatrização/fisiologia , Animais , Dorso , Transfusão de Sangue , Hematócrito , Distribuição Aleatória , Suínos
13.
Science ; 227(4693): 1463, 1985 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-17777777
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