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1.
Mol Phylogenet Evol ; 142: 106659, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639525

RESUMO

A major goal of phylogenetic systematics is to understand both the patterns of diversification and the processes by which these patterns are formed. Few studies have focused on the ancient, species-rich Magnoliales clade and its diversification pattern. Within Magnoliales, the pantropically distributed Annonaceae are by far the most genus-rich and species-rich family-level clade, with c. 110 genera and c. 2,400 species. We investigated the diversification patterns across Annonaceae and identified traits that show varied associations with diversification rates using a time-calibrated phylogeny of 835 species (34.6% sampling) and 11,211 aligned bases from eight regions of the plastid genome (rbcL, matK, ndhF, psbA-trnH, trnL-F, atpB-rbcL, trnS-G, and ycf1). Twelve rate shifts were identified using BAMM: in Annona, Artabotrys, Asimina, Drepananthus, Duguetia, Goniothalamus, Guatteria, Uvaria, Xylopia, the tribes Miliuseae and Malmeeae, and the Desmos-Dasymaschalon-Friesodielsia-Monanthotaxis clade. TurboMEDUSA and method-of-moments estimator analyses showed largely congruent results. A positive relationship between species richness and diversification rate is revealed using PGLS. Our results show that the high species richness in Annonaceae is likely the result of recent increased diversification rather than the steady accumulation of species via the 'museum model'. We further explore the possible role of selected traits (habit, pollinator trapping, floral sex expression, pollen dispersal unit, anther septation, and seed dispersal unit) in shaping diversification patterns, based on inferences of BiSSE, MuSSE, HiSSE, and FiSSE analyses. Our results suggest that the liana habit, the presence of circadian pollinator trapping, androdioecy, and the dispersal of seeds as single-seeded monocarp fragments are closely correlated with higher diversification rates; pollen aggregation and anther septation, in contrast, are associated with lower diversification rates.


Assuntos
Annonaceae/classificação , Annonaceae/genética , Biodiversidade , Genoma de Planta , Filogenia , Plastídeos/genética
2.
Compend Contin Educ Dent ; 18(5): 430-3, 436, 438 passim, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9533356

RESUMO

Uncontrollable disruptive gagging makes most dental procedures impossible to perform. Well-intentioned interventions by dentists often fail because of the inability to differentiate between psychogenic disruptive gagging and disruptive gagging of somatic origin. To help the clinician differentiate the diagnosis and management of somatogenic disruptive gagging from the psychogenic form, a review of the pertinent literature, diagnostic criteria, treatment recommendations, and a clinical case of psychogenic disruptive gagging are presented.


Assuntos
Ansiedade ao Tratamento Odontológico/psicologia , Técnica de Moldagem Odontológica/efeitos adversos , Engasgo , Transtornos Psicofisiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicofisiológicos/diagnóstico , Transtornos Psicofisiológicos/terapia , Reflexo , Terapia de Relaxamento
3.
Poult Sci ; 67(8): 1166-73, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3217305

RESUMO

The nutritional value of raw and autoclaved grain amaranth, its milling fractions (perisperm and bran), fat-free flour, and of popped amaranth was evaluated for growing chickens. The control diet, which was composed primarily of corn and soybean meal, contained 3.06 kcal apparent ME (AME)/g and 23.6% CP. Test diets contained about the same AME and CP levels, and the following levels of the test samples: whole grain amaranth flour, 61.46%; fat-free flour, 62.10%; perisperm, 49.50%; bran, 35.30%; and popped amaranth, 61.10%. Two groups of six unsexed broiler chicks each, 2-day old when received, were used per diet. Chickens fed diets containing autoclaved grain amaranth or its fractions over 17 or 18 days grew as well as those fed the control diet. Feeding of popped amaranth resulted in poorer performance. On a dry matter basis, AME values of raw grain amaranth flour, fat-free flour, perisperm, bran, and popped amaranth were found to be 3.21, 3.09, 3.68, 3.06, and 2.98 kcal/g, respectively. Respective AME values for the first four autoclaved samples were 3.04, 2.94, 3.10, and 3.17 kcal/g. Autoclaved grain amaranth and its perisperm fraction replaced corn in the diets of growing chickens with similar performance results.


Assuntos
Ração Animal , Compostos Azo , Peso Corporal , Galinhas/crescimento & desenvolvimento , Grão Comestível , Animais , Valor Nutritivo
4.
Poult Sci ; 66(3): 493-9, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3601860

RESUMO

Rice bran either raw or processed in an extrusion cooker at 130 C was fed to meat strain chickens for 25 days after hatch. Either full fat or hexane-extracted rice bran was placed in the diet at the equivalent of 60% full fat bran. Raw full fat bran for one diet was stored at -23 C until fed, whereas rice bran for all other diets was stored at 32 C. Four experiments were conducted at 6-week intervals. Free fatty acid (FFA) content in oil from raw rice bran stored at the elevated temperature reached 81% by the start of the final experiment whereas FFA in stabilized bran oil remained at about 3%. Chickens fed stabilized rice bran made significantly greater gains than chickens fed raw bran diets. Feed efficiency was superior for chickens fed either full fat or extracted stabilized bran compared with full fat bran stored at either 32 or -23 C. Feed conversion for extracted raw bran was intermediate between stabilized bran and full fat raw bran. Raw bran stored at 32 C (with elevated FFA content) tended to produce lower gains than the frozen raw bran. Analysis of the combined data from all four trials indicated that raw bran held at 32 C produced the lowest gains among all of the diets.


Assuntos
Ração Animal , Galinhas/crescimento & desenvolvimento , Oryza , Animais , Peso Corporal , Masculino , Valor Nutritivo
5.
S Afr Med J ; 69(2): 103-6, 1986 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-2417339

RESUMO

The effects of free and liposome-encapsulated bleomycin and adriamycin on a human hepatocellular carcinoma cell line were studied in vitro. Free and encapsulated bleomycin inhibited cell growth over 24 hours by the same amount, but DNA synthesis was inhibited more by the encapsulated form. Twenty-five per cent of the cell population showed drug resistance to the free drug, whereas this decreased to 17% with encapsulated bleomycin. These results suggest that the cell membrane plays a role in bleomycin resistance, and that cell death is not solely due to inhibition of DNA synthesis. Encapsulated adriamycin inhibited cell growth and DNA synthesis by the same amount or less than the free drug. Possible explanations are that adriamycin exerts its main cytotoxic action by interacting with the cell surface, or that at the low concentrations used, free drug is taken up more efficiently than the encapsulated drug. Liposomes as drug carriers constitute a useful system for studying the basic mechanisms involved in drug action and in particular the role played by cell membranes.


Assuntos
Bleomicina/farmacologia , Membrana Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Lipossomos/metabolismo , Bleomicina/metabolismo , Carcinoma Hepatocelular , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Doxorrubicina/metabolismo , Resistência a Medicamentos , Humanos , Neoplasias Hepáticas
9.
Am J Clin Nutr ; 32(6): 1188-91, 1979 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-312597

RESUMO

The in vivo dietary fiber contents of wheat milling fractions and wheat foods, determined in rat feeding experiments, were compared with dietary fiber values determined in vitro with pronase alpha-amylase digestion. Both types of dietary fiber values were compared with crude fiber and neutral detergent fiber values in the same materials. Regression analyses indicated close correlation amongst all values determined. It appears that laboratory analysis for crude fiber, neutral detergent fiber, or in vitro dietary fiber accurately predicts in vivo dietary fiber (rats) for wheat milling fractions when the laboratory result is adjusted by means of an appropriate regression equation.


Assuntos
Celulose/análise , Fibras na Dieta/análise , Polissacarídeos/análise , Triticum/análise , Animais , Bioensaio , Pão/análise , Detergentes , Farinha/análise , Manipulação de Alimentos , Pronase , Ratos , Análise de Regressão , alfa-Amilases
11.
Am J Clin Nutr ; 31(12): 2136-9, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-727160

RESUMO

Rat feeding studies were used to measure the dietary fiber content of wheat milling fractions, white and whole wheat breads, and wheat-based breakfast foods. Straight line correlations were established for the relationships between dietary fiber (y) and crude fiber (x) where y = 4.17x--0.27 (r = 0.997, P less than 0.01). Dietary fiber values ranged from 1.1% (flour) to 53.4% (bran), dry weight basis.


Assuntos
Celulose/análise , Fibras na Dieta/análise , Digestão , Triticum , Animais , Pão , Grão Comestível , Manipulação de Alimentos , Ratos
12.
S Afr Med J ; 53(6): 204-8, 1978 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-77562

RESUMO

A dose of 10 microgram/ml bleomycin inhibited the growth of oesophageal carcinoma cells and non-squamous cells in vitro. Drug concentration, density of cells and the time of exposure to the drug were important variables. The oesophagus cancer cells increased in volume by 2,5 +/- 0,2% per hour until the onset of lysis at 96 hours. The effects of the drug were irreversible even when the exposure time was only 24 hours. A certain proportion of the cell population was resistant to bleomycin and these cells remained resistant when the drug was removed for 48 hours and then replaced. No drug inactivation or uptake could be detected with the use of microbiological assay after 4 days of incubation with 3 cell types. There is poor correlation between in vitro and in vivo results.


Assuntos
Bleomicina/farmacologia , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Contagem de Células , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Depressão Química , Humanos , Técnicas In Vitro
16.
Proc Natl Acad Sci U S A ; 71(1): 26-9, 1974 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-4521055

RESUMO

Cell fusion between opposite mating types 5 and 21 of the yeast Hansenula wingei is initiated by a strong sexual agglutination reaction. The mating factors responsible for the specificity of cellular recognition are complementary glycoproteins which form a physical complex in vitro. The complex is assayed by recovery of agglutination activity of the multivalent 5-factor after the univalent 21-factor has been inactivated by treatment of the complex with alkali. The 5-factor.21-factor complex, purified on Sepharose 6B, is large (several million daltons) and heterogeneous. The three peaks of 5-factor activity contain a number of combining sites proportional to molecular size.


Assuntos
Proteínas Fúngicas/fisiologia , Glicoproteínas/fisiologia , Reprodução , Leveduras/fisiologia , Sítios de Ligação , Adesão Celular , Fusão Celular , Cromatografia em Gel , Proteínas Fúngicas/análise , Proteínas Fúngicas/metabolismo , Glicoproteínas/análise , Glicoproteínas/metabolismo , Peso Molecular , Leveduras/citologia
20.
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