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1.
Appl Opt ; 61(14): 4215-4225, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256099

RESUMO

During 2019, an infrared camera, the compact thermal imager (CTI), recorded 15 million images of the Earth from the International Space Station. CTI is based on strained-layer superlattice (SLS) detector technology. The camera covered the spectral range from 3 to 11 µm in two spectral channels, 3.3-5.4 and 7.8-10.7 µm. Individual image frames were 26×21km2 projected on the ground, with 82 m pixel resolution. A frame time of 2.54 s created continuous image swaths with a 13% along-track image overlap. Upper limits determined on the ground and in flight for the electronic offset, read noise, and dark current demonstrated the stability of the SLS detector and camera over many months. Temperature calibration was established using a combination of preflight and in-flight measurements. A narrowband approximation of temperature as a function of photon counts produced an analytic relationship covering a temperature range of 0°-400°C. Examples of CTI images illustrate temperature retrievals over sea ice, urban and agricultural areas, desert, and wildfires.

2.
Appl Opt ; 56(18): 5274-5294, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047582

RESUMO

The Cassini spacecraft orbiting Saturn carries the composite infrared spectrometer (CIRS) designed to study thermal emission from Saturn and its rings and moons. CIRS, a Fourier transform spectrometer, is an indispensable part of the payload providing unique measurements and important synergies with the other instruments. It takes full advantage of Cassini's 13-year-long mission and surpasses the capabilities of previous spectrometers on Voyager 1 and 2. The instrument, consisting of two interferometers sharing a telescope and a scan mechanism, covers over a factor of 100 in wavelength in the mid and far infrared. It is used to study temperature, composition, structure, and dynamics of the atmospheres of Jupiter, Saturn, and Titan, the rings of Saturn, and surfaces of the icy moons. CIRS has returned a large volume of scientific results, the culmination of over 30 years of instrument development, operation, data calibration, and analysis. As Cassini and CIRS reach the end of their mission in 2017, we expect that archived spectra will be used by scientists for many years to come.

4.
J Med Entomol ; 52(5): 937-46, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26336244

RESUMO

Determining the time of colonization of human or other animal remains by blow flies (Diptera: Calliphoridae) can play an important role in criminal investigations. However, blow fly presence in a given area is strongly influenced by abiotic and biotic variables such as temperature and habitat. We wanted to assess the biodiversity of adult blow flies in New Jersey, USA, where very little is known about these taxa. Toward that end we collected adult blow flies biweekly from traps baited with bovine liver and placed across three regions in New Jersey over a 2-yr period (2011-2013). We collected and identified 9,257 adult calliphorids, comprising six genera and 12 species. Blow fly assemblages composed of these species varied by season, but community composition did not vary among regions within a given season. Three species, Lucilia coeruleiviridis (Macquart), Lucilia sericata (Meigen), and Phormia regina (Meigen) comprised 88.5% of all adult blow flies collected (42.6, 25.9, 20.0%, respectively). Combining all regions, the dominant species for both spring and summer was L. coeruleiviridis comprising 35.1% of all adults caught in spring and 64.1% in summer. P. regina was the dominant species in fall, totaling 40.1% of all adults caught and Calliphora vicina (Robineau-Desvoidy) was the dominant species for winter, totaling 44.8% of all adults caught. Our findings provide the first assessment of blow fly communities in New Jersey, and these results can be applied to surrounding states where data are severely lacking for forensic application.


Assuntos
Biodiversidade , Dípteros/fisiologia , Estações do Ano , Animais , Dípteros/crescimento & desenvolvimento , Entomologia , Ciências Forenses , Geografia , Larva/crescimento & desenvolvimento , Larva/fisiologia , New Jersey , Óvulo/crescimento & desenvolvimento , Óvulo/fisiologia
5.
Bull Entomol Res ; 105(5): 598-606, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26072908

RESUMO

Emerald ash borer (EAB), Agrilus planipennis, is a serious invasive forest pest in North America responsible for killing tens to hundreds of millions of ash trees since it was accidentally introduced in the 1990 s. Although host-plant resistance and natural enemies are known to be important sources of mortality for EAB in Asia, less is known about the importance of different sources of mortality at recently colonized sites in the invaded range of EAB, and how these relate to host tree crown condition. To further our understanding of EAB population dynamics, we used a large-scale field experiment and life-table analyses to quantify the fates of EAB larvae and the relative importance of different biotic mortality factors at 12 recently colonized sites in Maryland. We found that the fates of larvae were highly dependent on EAB life stage and host tree crown condition. In relatively healthy trees (i.e., with a low EAB infestation) and for early instars, host tree resistance was the most important mortality factor. Conversely, in more unhealthy trees (i.e., with a moderate to high EAB infestation) and for later instars, parasitism and predation were the major sources of mortality. Life-table analyses also indicated how the lack of sufficient levels of host tree resistance and natural enemies contribute to rapid population growth of EAB at recently colonized sites. Our findings provide further evidence of the mechanisms by which EAB has been able to successfully establish and spread in North America.


Assuntos
Besouros/fisiologia , Fraxinus/fisiologia , Estágios do Ciclo de Vida/fisiologia , Animais , Larva/fisiologia , Dinâmica Populacional
6.
Nature ; 427(6970): 132-5, 2004 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-14712270

RESUMO

The Earth's equatorial stratosphere shows oscillations in which the east-west winds reverse direction and the temperatures change cyclically with a period of about two years. This phenomenon, called the quasi-biennial oscillation, also affects the dynamics of the mid- and high-latitude stratosphere and weather in the lower atmosphere. Ground-based observations have suggested that similar temperature oscillations (with a 4-5-yr cycle) occur on Jupiter, but these data suffer from poor vertical resolution and Jupiter's stratospheric wind velocities have not yet been determined. Here we report maps of temperatures and winds with high spatial resolution, obtained from spacecraft measurements of infrared spectra of Jupiter's stratosphere. We find an intense, high-altitude equatorial jet with a speed of approximately 140 m s(-1), whose spatial structure resembles that of a quasi-quadrennial oscillation. Wave activity in the stratosphere also appears analogous to that occurring on Earth. A strong interaction between Jupiter and its plasma environment produces hot spots in its upper atmosphere and stratosphere near its poles, and the temperature maps define the penetration of the hot spots into the stratosphere.

7.
Science ; 367(6481)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32054693

RESUMO

The outer Solar System object (486958) Arrokoth (provisional designation 2014 MU69) has been largely undisturbed since its formation. We studied its surface composition using data collected by the New Horizons spacecraft. Methanol ice is present along with organic material, which may have formed through irradiation of simple molecules. Water ice was not detected. This composition indicates hydrogenation of carbon monoxide-rich ice and/or energetic processing of methane condensed on water ice grains in the cold, outer edge of the early Solar System. There are only small regional variations in color and spectra across the surface, which suggests that Arrokoth formed from a homogeneous or well-mixed reservoir of solids. Microwave thermal emission from the winter night side is consistent with a mean brightness temperature of 29 ± 5 kelvin.

8.
Science ; 367(6481)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32054694

RESUMO

The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, is composed of primitive objects preserving information about Solar System formation. In January 2019, the New Horizons spacecraft flew past one of these objects, the 36-kilometer-long contact binary (486958) Arrokoth (provisional designation 2014 MU69). Images from the flyby show that Arrokoth has no detectable rings, and no satellites (larger than 180 meters in diameter) within a radius of 8000 kilometers. Arrokoth has a lightly cratered, smooth surface with complex geological features, unlike those on previously visited Solar System bodies. The density of impact craters indicates the surface dates from the formation of the Solar System. The two lobes of the contact binary have closely aligned poles and equators, constraining their accretion mechanism.

9.
Science ; 279(5352): 844-7, 1998 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-9452380

RESUMO

Absorption lines of hot water have been identified in the infrared spectra of Betelgeuse (alpha Orionis) and Antares (alpha Scorpii) near 12.3 micrometers (811 to 819 wavenumbers). The water lines originate in the atmospheres of the stars, not in their circumstellar material. The spectra are similar in structure to umbral sunspot spectra. Pure rotation water lines of this type will occur throughout the spectra of cool stars at wavelengths greater than 10 micrometers. From the water spectra, the upper limit for the temperature in the line formation region in both stars is 2800 kelvin. The water column density in both stars is (3 +/- 2) x 10(18) molecules per square centimeter, yielding an abundance relative to atomic hydrogen of n(H2O)/n(H) approximately 10(-)7.


Assuntos
Astronomia , Água/análise , Fenômenos Astronômicos , Meio Ambiente Extraterreno , Espectrofotometria Infravermelho
10.
Astrophys J Lett ; 854(2)2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32373309

RESUMO

In this paper we report the monitoring of seasonal evolution near Titan's poles. We find Titan's south pole to exhibit since 2010 a strong temperature decrease and a dramatic enhancement of several trace species such as complex hydrocarbons and nitriles (HC3N and C6H6 in particular) previously only observed at high northern latitudes (Coustenis et al. 2016 and references therein). This results from the seasonal change on Titan going from winter (2002) to summer (2017) in the north and, at the same time, the onset of winter in the south pole. During this transition period atmospheric components with longer chemical lifetimes linger in the north undergoing slow photochemical destruction, while those with shorter lifetimes decrease and reappear in the south. An opposite effect was expected in the north, but not observed with certainty until now. We present here an analysis of high-resolution nadir spectra acquired by Cassini/CIRS at in the past years and describe the temperature and composition variations near Titan's poles. From 2013 until 2016, the northern polar region has shown a temperature increase of 10 K, while the south has shown a more significant decrease (up to 25 K) in a similar period of time. While the south polar region is continuously enhanced since about 2012, the chemical content in the north is finally showing a clear depletion for most molecules only since 2015. This is indicative of a non-symmetrical response to the seasons in Titan's stratosphere that can set constraints on photochemical and GCM models.

11.
Science ; 351(6279): aad9189, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26989260

RESUMO

The New Horizons spacecraft mapped colors and infrared spectra across the encounter hemispheres of Pluto and Charon. The volatile methane, carbon monoxide, and nitrogen ices that dominate Pluto's surface have complicated spatial distributions resulting from sublimation, condensation, and glacial flow acting over seasonal and geological time scales. Pluto's water ice "bedrock" was also mapped, with isolated outcrops occurring in a variety of settings. Pluto's surface exhibits complex regional color diversity associated with its distinct provinces. Charon's color pattern is simpler, dominated by neutral low latitudes and a reddish northern polar region. Charon's near-infrared spectra reveal highly localized areas with strong ammonia absorption tied to small craters with relatively fresh-appearing impact ejecta.

12.
Science ; 351(6279): aae0030, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26989256

RESUMO

The New Horizons mission has provided resolved measurements of Pluto's moons Styx, Nix, Kerberos, and Hydra. All four are small, with equivalent spherical diameters of ~40 kilometers for Nix and Hydra and ~10 kilometers for Styx and Kerberos. They are also highly elongated, with maximum to minimum axis ratios of ~2. All four moons have high albedos (~50 to 90%) suggestive of a water-ice surface composition. Crater densities on Nix and Hydra imply surface ages of at least 4 billion years. The small moons rotate much faster than synchronous, with rotational poles clustered nearly orthogonal to the common pole directions of Pluto and Charon. These results reinforce the hypothesis that the small moons formed in the aftermath of a collision that produced the Pluto-Charon binary.

13.
Aliment Pharmacol Ther ; 15(1): 105-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11136283

RESUMO

AIM: A double-blind, placebo-controlled study to assess the duration of effect of lansoprazole 30 mg o.m. on intragastric pH, acid secretion, gastrin levels, the potential for rebound acidity, and the relationship between gastric acid and drug pharmacokinetic parameters. METHODS: Sixteen subjects were treated with lansoprazole 30 mg daily or placebo for 14 days, followed by a 7-day post-dosing period and a post-study evaluation on day 28. Ambulatory 24-h pH was recorded and pentagastrin-stimulated acid secretion measured. Plasma kinetics of lansoprazole were determined. RESULTS: Mean intragastric pH in the lansoprazole group increased significantly (P < 0.05) from baseline to day 14 compared to placebo. After cessation of treatment, secretory activity, as measured by intragastric pH, basal acid output and stimulated acid output, returned to baseline in 2 to 4 days without any overshoot, indicating the absence of acid rebound. Lansoprazole's terminal disposition half-life was 1.11 h. Mean pH and serum gastrin returned to baseline with half-lives of 22 and 19 h, respectively. CONCLUSIONS: Lansoprazole 30 mg daily significantly increases mean intragastric pH without producing acid rebound. Regeneration of acid production depends primarily on de novo synthesis of the acid pump.


Assuntos
Inibidores Enzimáticos/farmacologia , Ácido Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Método Duplo-Cego , Determinação da Acidez Gástrica , Gastrinas/sangue , Humanos , Lansoprazol , Masculino , Omeprazol/efeitos adversos , Omeprazol/farmacocinética , Omeprazol/uso terapêutico , Pentagastrina/farmacologia , Fatores de Tempo
14.
Aliment Pharmacol Ther ; 9(1): 25-31, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7766740

RESUMO

BACKGROUND: Lansoprazole is a new proton pump inhibitor which produces prolonged decrease of gastric acidity. The aim of this study was to compare lansoprazole to a standard dose of ranitidine in the treatment of patients with reflux oesophagitis. METHODS: Two hundred and forty-seven patients with erosive oesophagitis were randomly assigned to 8 weeks of treatment with either 30 mg lansoprazole once daily or 150 mg ranitidine twice daily. RESULTS: Two hundred and forty-two patients were included in the analysis. Lansoprazole (30 mg) daily, healed oesophagitis in 92.1% of patients after 8 weeks of treatment. This was significantly superior to 150 mg ranitidine b.d.s. which healed oesophagitis in 69.9% of patients (P < 0.001). Relief of reflux symptoms was superior with lansoprazole to that with ranitidine. Both lansoprazole and ranitidine were well tolerated with no serious drug-related adverse events noted. CONCLUSION: Lansoprazole, 30 mg once daily, is highly effective and safe in the short-term treatment of erosive oesophagitis.


Assuntos
Antiulcerosos/uso terapêutico , Esofagite Péptica/tratamento farmacológico , Omeprazol/análogos & derivados , Inibidores da Bomba de Prótons , Ranitidina/uso terapêutico , 2-Piridinilmetilsulfinilbenzimidazóis , Administração Oral , Consumo de Bebidas Alcoólicas , Antiulcerosos/administração & dosagem , Antiulcerosos/efeitos adversos , Cafeína/administração & dosagem , Método Duplo-Cego , Avaliação de Medicamentos , Feminino , Gastroscopia , Humanos , Lansoprazol , Estudos Longitudinais , Masculino , Omeprazol/administração & dosagem , Omeprazol/efeitos adversos , Omeprazol/uso terapêutico , Ranitidina/administração & dosagem , Ranitidina/efeitos adversos , Fumar
15.
Aliment Pharmacol Ther ; 13(7): 959-67, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10383532

RESUMO

BACKGROUND: Maintenance antisecretory therapy is often used to prevent duodenal ulcer recurrence and control symptoms. This study compared the efficacy and safety of lansoprazole 15 mg and 30 mg daily with placebo in preventing ulcer recurrence in patients with a recent history of duodenal ulcer disease. METHODS: Fifty-six patients were treated with either lansoprazole 15 mg, 30 mg or placebo o.m. RESULTS: Within 1 month of study initiation, 27% (four out of 15) of placebo-treated patients experienced ulcer recurrence as compared to 13% (two out of 15) and 6% (one out of 18) of lansoprazole 15 mg and 30 mg treated patients, respectively. Median time to first ulcer recurrence was > 12 months in lansoprazole patients. At Month 12, significantly (P < 0.001) more lansoprazole 15 mg patients (70%) and lansoprazole 30 mg patients (85%) remained healed. Eighty-two per cent of lansoprazole 15 mg and 76% of lansoprazole 30 mg patients remained asymptomatic during the entire study period. All placebo patients became symptomatic, experienced ulcer recurrence, or withdrew from the study by month six. The incidence of adverse events was comparable among the three treatment groups. CONCLUSIONS: Lansoprazole safely and effectively reduces duodenal ulcer recurrence and ulcer-related symptoms.


Assuntos
Antiulcerosos/administração & dosagem , Úlcera Duodenal/metabolismo , Úlcera Duodenal/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/farmacologia , Omeprazol/análogos & derivados , Inibidores da Bomba de Prótons , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Método Duplo-Cego , Resistência a Medicamentos , Feminino , Mucosa Gástrica/metabolismo , Gastrinas/sangue , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Recidiva , Resultado do Tratamento , Estados Unidos
16.
Aliment Pharmacol Ther ; 9(5): 521-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8580272

RESUMO

BACKGROUND: Lansoprazole is a new proton pump inhibitor for the treatment of peptic ulcer disease. METHODS: A double-blind, multicentre study was undertaken in 296 patients with endoscopically proven duodenal ulcer to compare the efficacy and safety of lansoprazole 15, 30 or 60 mg with placebo. Ulcer healing was documented by endoscopy at 2 and 4 weeks; patients whose ulcers healed after 4 weeks were followed for up to 6 months post-treatment. RESULTS: Four-week healing rates of 89.4%, 91.7% and 89.9% were obtained with lansoprazole 15, 30 and 60 mg, respectively, compared with 46.1% on placebo (P < 0.001). All three doses of lansoprazole produced rapid symptom relief, although patients taking 60 mg lansoprazole required fewer antacids than did those taking 15 mg. At 6 months, the percentages of patients healed were 45.3%, 40.0% and 38.4% in the lansoprazole 15, 30 and 60 mg dosage groups, respectively, and 25.3% for the placebo group. No significant adverse events were documented during the period of this trial. CONCLUSION: Lansoprazole is an effective and safe treatment for duodenal ulcer and the 15 mg dose is as effective as 30 or 60 mg.


Assuntos
Antiulcerosos/uso terapêutico , Úlcera Duodenal/tratamento farmacológico , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Dor Abdominal/tratamento farmacológico , Adulto , Idoso , Antiulcerosos/administração & dosagem , Antiulcerosos/efeitos adversos , Método Duplo-Cego , Úlcera Duodenal/sangue , Duodenoscopia , Feminino , Gastrinas/sangue , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Omeprazol/efeitos adversos , Omeprazol/uso terapêutico , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
17.
Aliment Pharmacol Ther ; 6(3): 359-72, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1600052

RESUMO

This study examined the effects of dose and time of administration of lansoprazole on gastric pH and serum gastrin in healthy male volunteers. Three groups of six subjects received 10, 20 or 60 mg doses of lansoprazole or placebo. Doses were administered at 22.00 hours daily for 7 days. An additional 18 subjects received once daily 30 mg oral doses of lansoprazole or placebo; these subjects were dosed at either 08.00 hours or 22.00 hours in a randomized, crossover fashion with a 2-week washout period. Gastric pH was monitored for 24 h following the first and final dose, and 1 week following the completion of dosing. Lansoprazole, at all doses except 20 mg/day, significantly increased the median 24-hour gastric pH following 7 days of dosing (P less than 0.05). In addition, morning dosing in the 30-mg crossover group led to a higher 24-h median pH than evening dosing (P = 0.003). There was no difference in night-time median pH between morning and evening dosing. Morning dosing also led to a significant increase in gastric pH on study Day 1 (P less than 0.05). Plasma concentrations of lansoprazole were highly variable between subjects, but there was a significant correlation between AUC and the median 24-h gastric pH. Plasma concentrations and AUCs were higher on Day 7 than on Day 1 for subjects receiving 10 or 20 mg, but not for those receiving 30 or 60 mg doses. Lansoprazole bioavailability demonstrated a circadian effect manifested by higher plasma concentrations following morning dosing. Serum gastrin concentrations were elevated in all active medication groups.


Assuntos
Gastrinas/sangue , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Ritmo Circadiano/efeitos dos fármacos , Determinação da Acidez Gástrica , Humanos , Lansoprazol , Masculino , Omeprazol/sangue , Omeprazol/farmacocinética
18.
Aliment Pharmacol Ther ; 12(4): 321-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9690720

RESUMO

BACKGROUND: Proton pump inhibitors have been found to be effective in numerous studies in patients with peptic ulcer disease, particularly associated with Helicobacter pylori and gastro-oesophogeal reflux disorders. Optimal healing rates of antisecretory therapy for peptic acid disease is dependent upon the degree and duration of acid suppression and the length of treatment. OBJECTIVE: To evaluate the extent and duration of gastric acid suppression of several lansoprazole regimens, administered for 5 consecutive days in 32 healthy adult male subjects. METHODS: Intragastric 24-h pH monitoring was performed in 32 healthy subjects in a randomized, double-blind, four-way crossover study. Sixteen subjects (Group 1) received lansoprazole 30 mg o.d. (once daily), 15 mg b.d. (twice daily), 30 mg b.d. and 30 mg t.d.s. (three times a day) for 5 days; and 16 subjects (Group 2) received lansoprazole 30 mg o.d., 60 mg o.d., 60 mg b.d. and 60 mg t.d.s. for 5 days. RESULTS: Mean 24-h intragastric pH values for lansoprazole 30 mg o.d., 15 mg b.d., 30 mg b.d. and 30 mg t.d.s. were 4.47, 4.57, 5.07 and 5.63, respectively. Multiple-dose regimens of lansoprazole 30 mg b.d. and t.d.s. produced greater acid suppression compared to lansoprazole 30 mg o.d. and 15 mg b.d. There was no significant difference in acid suppression between lansoprazole 30 mg o.d. and 15 mg b.d. Mean 24-h intragastric pH values for lansoprazole 30 mg o.d., 60 mg o.d., 60 mg b.d. and 60 mg t.d.s. were 4.13, 4.45, 5.19 and 5.13, respectively. Multiple-dose regimens of lansoprazole 60 mg b.d. and t.d.s. produced significantly greater acid suppression compared to lansoprazole 30 mg o.d. and 60 mg o.d. There was no significant difference in acid suppression between lansoprazole 30 mg o.d. and 60 mg o.d. Lansoprazole 30 mg t.d.s., 60 mg b.d. and 60 mg t.d.s. produced significantly greater percentage time above pH 3, 4, 5 and 6 than did lansoprazole 30 mg o.d. Post-regimen serum gastrin values increased by 50-130% from pre-study mean values but remained within normal range and returned to pre-study values 7-14 days post-dosing. CONCLUSIONS: Multiple-dose regimens of lansoprazole (> or =30 mg b.d. for 5 days) produce significantly increased intragastric pH and significantly longer duration of increased intragastric pH than does lansoprazole 30 mg administered once daily.


Assuntos
Antiulcerosos/farmacologia , Ácido Gástrico/metabolismo , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Administração Oral , Adulto , Antiulcerosos/administração & dosagem , Antiulcerosos/uso terapêutico , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Refluxo Gastroesofágico/tratamento farmacológico , Humanos , Lansoprazol , Masculino , Omeprazol/administração & dosagem , Omeprazol/farmacologia , Omeprazol/uso terapêutico , Úlcera Péptica/tratamento farmacológico
19.
Thromb Res ; 73(6): 371-84, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8073390

RESUMO

Hemorrhagic and thrombotic complications are common in the term and preterm infant. Limited information is currently available about neonatal platelet structure and function, and how these may predispose infants to bleeding problems. This study comparing platelet ultrastructure of 71 different term and preterm infants with that of 15 adult control subjects revealed certain platelet morphological differences. Specifically, the adult platelets had more pseudopods, larger glycogen deposits, more visible microtubular structure, markedly fewer alpha granules, and smaller areas/perimeters than the infant platelets. Also, in infants greater than 31 weeks gestation, the platelets of vaginally-delivered infants were larger than those of both infants delivered by C-section and normal adults. These differences in platelet size and morphology may be related to developmental differences and/or the stress of delivery. These findings provide a framework for further exploration of neonatal platelet structure and function.


Assuntos
Plaquetas/ultraestrutura , Recém-Nascido Prematuro/sangue , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Valores de Referência , Fatores de Risco
20.
Science ; 318(5848): 223-5, 2007 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17932284

RESUMO

Several observations of Jupiter's atmosphere made by instruments on the New Horizons spacecraft have implications for the stability and dynamics of Jupiter's weather layer. Mesoscale waves, first seen by Voyager, have been observed at a spatial resolution of 11 to 45 kilometers. These waves have a 300-kilometer wavelength and phase velocities greater than the local zonal flow by 100 meters per second, much higher than predicted by models. Additionally, infrared spectral measurements over five successive Jupiter rotations at spatial resolutions of 200 to 140 kilometers have shown the development of transient ammonia ice clouds (lifetimes of 40 hours or less) in regions of strong atmospheric upwelling. Both of these phenomena serve as probes of atmospheric dynamics below the visible cloud tops.


Assuntos
Júpiter , Amônia , Atmosfera , Meio Ambiente Extraterreno , Astronave , Temperatura
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