Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
1.
J Fish Biol ; 91(4): 1139-1165, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28905373

RESUMO

Experimental investigation of the intensity of potential competitive interactions among increasingly abundant tropically-associated grey Lutjanus griseus and lane snapper Lutjanus synagris and resident northern Gulf of Mexico (nGOM) red snapper Lutjanus campechanus was undertaken in large outdoor mesocosms. In pair-wise interaction trials, compared with L. synagris, L. campechanus demonstrated significantly increased roving behaviour and predatory activity. While no significant difference in these activities was observed between L. campechanus and L. griseus, when all three snappers (Lutjanidae) were grouped together L. campechanus swimming activity significantly decreased in the presence of both tropically-associated species. Overall, L. campechanus were more active and aggressive predators and appear to be competitively resistant to L. griseus and L. synagris. As lower latitude species have continued to become increasingly prevalent in nGOM habitats and regional warming continues to affect resident reef-associated fishes, these findings contribute to the assessment of the effects of warming-related species shifts upon nGOM fishes and document current partial resilience of L. campechanus to climate-related expansions of tropical confamilials.


Assuntos
Comportamento Animal , Peixes/fisiologia , Migração Animal , Animais , Ecossistema , Golfo do México , Comportamento de Retorno ao Território Vital , Dinâmica Populacional , Alimentos Marinhos
2.
J Geophys Res Atmos ; 122(18): 10013-10024, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32724904

RESUMO

This study seeks to help better understand aerosol-cloud interactions by examining statistical relationships between aerosol properties and nearby low-altitude cloudiness using satellite data. The analysis of a global dataset of MODIS (Moderate Resolution Imaging Spectroradiometer) observations reveals that the positive correlation between cloudiness and aerosol optical depth (AOD) reported in earlier studies is strong throughout the globe and during both winter and summer. Typically, AOD is 30-50% higher on cloudier-than-average days than on less cloudy days. A combination of satellite observations and MERRA-2 global reanalysis data reveals that the correlation between cloud cover and AOD is strong for all aerosol types considered: sulfate, dust, carbon, and sea salt. The observations also indicate that in the presence of nearby clouds, aerosol size distributions tend to shift toward smaller particles over large regions of the Earth. This is consistent with a greater cloud-related increase in the AOD of fine mode than of coarse mode particles. The greater increase in fine mode AOD implies that the cloudiness-AOD correlation does not come predominantly from cloud detection uncertainties. Additionally, the results show that aerosol particle size increases near clouds even in regions where it decreases with increasing cloudiness. This suggests that the decrease with cloudiness comes mainly from changes in large-scale environment, rather than from clouds increasing the number or the size of fine mode aerosols. Finally, combining different aerosol retrieval algorithms demonstrated that quality assessment flags based on local variability can help identifying when the observed aerosol populations are affected by surrounding clouds.

3.
J Geophys Res Atmos ; 121(12): 7007-7025, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32908807

RESUMO

The bi-spectral method retrieves cloud optical thickness (τ) and cloud droplet effective radius (r e ) simultaneously from a pair of cloud reflectance observations, one in a visible or near infrared (VIS/NIR) band and the other in a shortwave-infrared (SWIR) band. A cloudy pixel is usually assumed to be horizontally homogeneous in the retrieval. Ignoring sub-pixel variations of cloud reflectances can lead to a significant bias in the retrieved τ and r e . In the literature, the retrievals of τ and r e are often assumed to be independent and considered separately when investigating the impact of sub-pixel cloud reflectance variations on the bi-spectral method. As a result, the impact on τ is contributed only by the sub-pixel variation of VIS/NIR band reflectance and the impact on r e only by the sub-pixel variation of SWIR band reflectance. In our new framework, we use the Taylor expansion of a two-variable function to understand and quantify the impacts of sub-pixel variances of VIS/NIR and SWIR cloud reflectances and their covariance on the τ and r e retrievals. This framework takes into account the fact that the retrievals are determined by both VIS/NIR and SWIR band observations in a mutually dependent way. In comparison with previous studies, it provides a more comprehensive understanding of how sub-pixel cloud reflectance variations impact the τ and r e retrievals based on the bi-spectral method. In particular, our framework provides a mathematical explanation of how the sub-pixel variation in VIS/NIR band influences the r e retrieval and why it can sometimes outweigh the influence of variations in the SWIR band and dominate the error in r e retrievals, leading to a potential contribution of positive bias to the r e retrieval. We test our framework using synthetic cloud fields from a large-eddy simulation and real observations from MODIS. The predicted results based on our framework agree very well with the numerical simulations. Our framework can be used to estimate the retrieval uncertainty from sub-pixel reflectance variations in operational satellite cloud products and to help understand the differences in τ and r e retrievals between two instruments.

4.
Antivir Ther ; 1(2): 77-88, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11321183

RESUMO

Thirty-four subjects with symptomatic HIV-1 infection, p24 antigenaemia, and CD4 cell counts > 200/mm3 were randomly assigned to receive treatment with either zidovudine (ZDV) orally, interferon-alpha (IFN-alpha) subcutaneously, or both at respective low (200 mg ZDV/ 2 million international units IFN-alpha (MIU)), middle (400 mg/4 MIU) or high (600 mg/6 MIU) daily dose levels for 12 weeks. Thereafter, all patients received combination therapy at the initially assigned dose level to a total of 96 weeks. This design permitted analysis by the combination index (CI) method, which demonstrated antiretroviral synergy between ZDV and IFN-alpha with respect to p24 antigen suppression. Over the first 12 weeks, combination therapy was acceptably tolerated, more so than IFN-alpha monotherapy, and it was significantly more active in suppressing antigenaemia than either of the monotherapies. Similarly, the high-dose combination was the most active dose level over weeks 12 to 96. Combination ZDV/IFN-alpha at the optimal dose level defined by this trial merits further study. In addition, the CI design strategy employed here may be useful for the investigation of new antiretroviral combinations.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Antivirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Interferon-alfa/uso terapêutico , Zidovudina/uso terapêutico , Administração Cutânea , Administração Oral , Adulto , Fármacos Anti-HIV/administração & dosagem , Antivirais/administração & dosagem , Contagem de Linfócito CD4 , Sinergismo Farmacológico , Quimioterapia Combinada , Tolerância a Medicamentos , Feminino , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/sangue , Humanos , Interferon-alfa/administração & dosagem , Masculino , Zidovudina/administração & dosagem
6.
Arch Biochem Biophys ; 251(2): 616-23, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3800388

RESUMO

Trypsin digestion of chicken gizzard myosin light chain kinase at limiting trypsin concentrations proceeds in stages. In the first stage, catalytic activity in the presence or absence of calcium and calmodulin decreases. In the second stage, activity in the absence of calcium increases, and the calcium-calmodulin complex no longer stimulates activity. The initial loss of activity is associated with the appearance of a 59,000-Da peptide that has been isolated and shown to have low catalytic activity. This peptide was further digested to a 55,000-Da peptide that has calcium-independent catalytic activity. This peptide has been isolated, and its affinities for the peptide substrate Kemptamide (Lys-Lys-Arg-Pro-Gln-Arg-Ala-Thr-Ser-Asn-Val-Phe-Ser-NH2) and ATP have been shown to be the same as those of the intact enzyme. Neither the 59,000-Da nor the 55,000-Da fragment binds calmodulin.


Assuntos
Quinase de Cadeia Leve de Miosina/metabolismo , Fragmentos de Peptídeos/isolamento & purificação , Tripsina/farmacologia , Cálcio/farmacologia , Calmodulina/farmacologia , Catálise , Cromatografia DEAE-Celulose , Densitometria , Ativação Enzimática/efeitos dos fármacos , Quinase de Cadeia Leve de Miosina/antagonistas & inibidores
7.
Antibiotiki ; 28(12): 908-11, 1983 Dec.
Artigo em Russo | MEDLINE | ID: mdl-6419671

RESUMO

Sensitivity of 492 microbial strains to 9 antibacterial drugs and their double combinations was studied. The MTC was determined with the method of serial dilutions in an apparatus MIC-2000 (Austria). The apparatus provides determination of the MTC simultaneously to 12 antibiotics in 8 dilutions or to 8 antibiotics in 12 dilutions.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Testes de Sensibilidade Microbiana
9.
Antibiotiki ; 25(8): 623-6, 1980 Aug.
Artigo em Russo | MEDLINE | ID: mdl-7406475

RESUMO

The time-course of tetraolean concentrations (according to tetracycline) in the lymph, blood and urine of 10 patients with various complicated acute inflammatory diseases of the organs of the abdominal cavity was studied. It was found that tetraolean used intramuscularly in the early postoperative periods was well absorbed into the lymph, reached its maximum level within 2 hours and exceeded that in the blood. During the following 8 hours the concentration of the drug in the lymph decreased but still remained much higher than that in the blood. Lymph sorption lowered the antibiotic lymph level to 30 per cent, which indicated the necessity of an adequate increase in the drug dose.


Assuntos
Linfa/metabolismo , Oleandomicina/metabolismo , Peritonite/metabolismo , Tetraciclina/metabolismo , Doença Aguda , Adsorção , Adulto , Combinação de Medicamentos , Feminino , Humanos , Cinética , Pessoa de Meia-Idade , Peritonite/complicações , Peritonite/terapia
11.
Antibiotiki ; 25(3): 222-6, 1980 Mar.
Artigo em Russo | MEDLINE | ID: mdl-7362229

RESUMO

Pharmacokinetics of kanamycin sulfate in the lymph, blood and urine of 12 patients with acute inflammatory diseases of the organs of the abdominal cavity was studied. The study showed that kanamycin sulfate administered intramuscularly was rapidly absorbed into the lymph and blood reaching the maximum levels within 2 hours of the administration. The therapeutic levels were preserved for at least 8 hours. The concentration of kanamycin in pure lymph by the method of lymphosorption was 20 per cent lower which was connected with the drug adsorption by the sorbents.


Assuntos
Abdome Agudo/metabolismo , Canamicina/metabolismo , Linfa/metabolismo , Abdome Agudo/complicações , Adulto , Idoso , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/metabolismo , Fatores de Tempo
14.
Antibiotiki ; 24(8): 623-6, 1979 Aug.
Artigo em Russo | MEDLINE | ID: mdl-485113

RESUMO

Ampicillin levels in the lymph, blood and urine were studied in 15 patients with various inflammatory diseases of the organs of the abdominal cavity. It was found that ampicillin administered intramuscularly to such patients at early postoperative periods was well absorbed not only to the blood but also to the lymph, reaching in parallel its maximum levels in an hour. After that the drug concentration in the lymph persisted for 6 hours and markedly exceeded that in the blood. Adsorption of the lymph lowered the antibiotic concentration in it to 25 per cent indicating the necessity for increasing the drug therapeutic doses.


Assuntos
Abdome Agudo/metabolismo , Ampicilina/metabolismo , Linfa/metabolismo , Abdome Agudo/terapia , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Hidratação , Humanos , Injeções Intramusculares , Cinética , Pessoa de Meia-Idade , Fatores de Tempo
15.
Antibiotiki ; 24(7): 526-31, 1979 Jul.
Artigo em Russo | MEDLINE | ID: mdl-380455

RESUMO

The study on sensitivity of clinical strains of the causative agents of purulent infections to carbenicillin showed that 34.6% of the staphylococcal strains, 48.1% of the E. coli strains and 40.3% of the Proteus strains were sensitive to the antibiotic. The strains of Ps. aeruginosa were characterized by moderate sensitivity to carbenicillin. The MTC for most of the isolates ranged within 25-128 microgram/ml. High therapeutic efficacy of carbenicillin in treatment of cases with purulent inflammatory processes of various localization was shown. Positive results were obtained in 82.5% of the adults and 76.2% of the premature infants treated with carbenicillin. A satisfactory therapeutic effect was observed in the cases with sepsis, diffuse purulent peritonitis and abscessing pneumonia treated with carbenicillin in combination with gentamicin.


Assuntos
Carbenicilina/uso terapêutico , Inflamação/tratamento farmacológico , Supuração/tratamento farmacológico , Adulto , Ampicilina/uso terapêutico , Ensaios Clínicos como Assunto , Avaliação de Medicamentos , Quimioterapia Combinada , Gentamicinas/uso terapêutico , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/tratamento farmacológico , Testes de Sensibilidade Microbiana
16.
Antibiotiki ; 23(9): 841-5, 1978 Sep.
Artigo em Russo | MEDLINE | ID: mdl-358914

RESUMO

Pharmacokinetics of 4 cephalosporanic antibiotics for parenteral use, i. e. cephaloridine, cephradine, cephazoline and cephacetryl was studied in surgical patients with normal function of the kidneys and liver. The first 3 drugs were well absorbed after intramuscular administration, their maximum serum levels being achieved during the first hour. High blood levels of cephacetryl were determined after its intravenous administration. When cephaloridine, cephradine and cephazoline were administered in equal doses, it was found that the first 2 drugs did not practically differ with respect to the values of the serum levels, the rate of elimination from the blood, the rate and level of excretion with the urine. Cephazoline was characterized by higher blood levels and slower elimination from the blood.


Assuntos
Cefalosporinas/metabolismo , Procedimentos Cirúrgicos Operatórios , Biofarmácia , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Humanos , Injeções Intramusculares , Cinética , Fatores de Tempo
17.
Vestn Khir Im I I Grek ; 121(8): 93-7, 1978 Aug.
Artigo em Russo | MEDLINE | ID: mdl-695216

RESUMO

An analysis of a qualitative composition of wound microflora grounded on the findings of the clinico-bacteriological examination of 315 cases with various pyo-inflammatory processes is presented here, and specific features of the species composition of wound microflora depending upon the character of a pyo-inflammatory process are shown. The sensitivity of staphylococcuses isolated from the wounds, to 19 antibacterial preparations is analyzed and recommendations on the most rational and differentiated use of antibacterial drugs in various forms of a purulent process of staphylococcal eti-logy are suggested.


Assuntos
Infecções Estafilocócicas/tratamento farmacológico , Infecção da Ferida Cirúrgica/tratamento farmacológico , Antibacterianos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/microbiologia
18.
J Exp Med ; 146(6): 1773-90, 1977 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-72782

RESUMO

The regulatory influence of the rat major histocompatibility complex (MHC) (Ag-B complex) on the specificity of cytotoxic T lymphocytes was investigated. It was shown that the effector cells were specific for the original Ag-B phenotype in rat systems in which the responder and stimulator cell populations were unquestionably MHC identical but expressed different minor alloantigens of viral antigens. However, combined in vivo immunization and restimulation in culture of lymphocytes from rat strains previously thought to be MHC compatible resulted in the generation of cytotoxic T lymphocytes which effectively lyse not only target cells from the specific stimulating strains but also, to varying degrees, target cells from third party strains regardless of their Ag-B haplotypes. Genetic analysis indicates that expression of these cytotoxic T-cell-defined ("CT") antigens, found on both T and B lymphocytes, detectable thus far only with cytotoxic lymphocytes, is controlled by a single locus which segregates in backcross populations with the rat MHC. Discrepancies between the nature of CT antigens of the rat Ag-B and I-region specificities of the mouse H-2 are discussed.


Assuntos
Linfócitos T/imunologia , Animais , Citotoxicidade Imunológica , Epitopos , Histocompatibilidade , Antígenos de Histocompatibilidade , Isoantígenos , Células Matadoras Naturais , Ratos
19.
Antibiotiki ; 22(9): 798-803, 1977 Sep.
Artigo em Russo | MEDLINE | ID: mdl-143905

RESUMO

The study of the dynamics of biogenic amines in the blood of patients provided to a certain extent determination of the possible thread of the drug complications. In this respect the serotonin level was of special significance. As for the reaction of leucocyte agglomeration it may be used before the treatment if there is a doubt in the tolerance of the antibacterial drug prescribed. Increased serotonin blood levels in this case also serve a confirmation of the thread of the possible allergic or toxic reaction in the patient.


Assuntos
Antibacterianos/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , 11-Hidroxicorticosteroides/sangue , Administração Oral , Adulto , Ampicilina/efeitos adversos , Carbenicilina/efeitos adversos , Ceruloplasmina/análise , Doxiciclina/efeitos adversos , Interações Medicamentosas , Feminino , Histamina/sangue , Humanos , Injeções Intramusculares , Leucócitos/imunologia , Masculino , Pessoa de Meia-Idade , Minociclina/efeitos adversos , Pivampicilina/efeitos adversos , Serotonina/sangue , Tetraciclinas/efeitos adversos , Fatores de Tempo , Triptofano/sangue
20.
Antibiotiki ; 22(8): 739-42, 1977 Aug.
Artigo em Russo | MEDLINE | ID: mdl-334053

RESUMO

Pharmacokinetics of 2 oral cephalosporin antibiotics, i.e. cephalexin and cephradin in surgical patients with normal function of the liver and kidneys was studied. Both the drugs were satisfactorily absorbed into the blood reaching the maximum level in 1 hour. The antibiotics were determined in close concentrations in the blood serum of the patients during 5 hours of the observation. No differences in the time of a two-fold decrease in the antibiotic serum level and the value of the area limited by the antibiotic blood level were found. Cephalexin and cephradin were excreted with the urine in equal amounts.


Assuntos
Cefalexina/metabolismo , Cefalosporinas/metabolismo , Cefradina/metabolismo , Absorção , Biofarmácia , Cápsulas , Cefalexina/urina , Cefradina/urina , Ensaios Clínicos como Assunto , Humanos , Cinética , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...