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1.
Animal ; 17(12): 101009, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37952301

RESUMO

The only common European Union (EU) legislation set up specifically to ensure the welfare of dairy cattle is for calves. As a consequence, there is wide diversity in how dairy cattle welfare is ensured in EU countries. A few countries have legal requirements for dairy cattle welfare, while in others, it is left to industry standards or niche production requirements, typically linked to various premium labels. In this paper, we compared animal welfare provisions in dairy cattle production across five countries with different combinations of legislative and other approaches: Denmark, Germany, the Netherlands, Sweden, and the United Kingdom. Firstly, we aimed to map the diversity of animal welfare initiatives. Secondly, we used the Benchmark method of expert valuations and weightings of the relative importance of individual welfare provisions. We found that Denmark and Sweden have the highest level of dairy cattle welfare provisions as measured by the Benchmark method, partly due to high legislative welfare requirements, followed by the United Kingdom, which has an extensive industry standard with very high uptake. Germany and the Netherlands, on the other hand, have lower levels of documented welfare provisions, and correspondingly a Benchmark score closer to a baseline defined by legal requirements at EU level. We also found differences in what elements of animal welfare were focussed on. Some initiatives emphasised fulfilling the social needs of cattle, while others focused more on space and freedom to move. Also, the countries with the highest Benchmark score had a relatively high level of production of organic and other specialty dairy products. We found the effect of national legislation or ambitious industry standards on dairy cattle welfare to be much larger than previous studies have found in either pigs or poultry. At a time when the EU is considering stepping up its efforts to improve animal welfare in terms of common minimum standards, the results of this study could have important policy implications. The diversity in the level of dairy cattle welfare standards found across countries may speak in favour of having shared minimum standards, both at EU level and globally. However, even among countries with a similar Benchmark score, we found a difference in the kinds of welfare provisions at work, which may make full harmonisation of standards more challenging.


Assuntos
Laticínios , Indústria de Laticínios , Animais , Bovinos , Suínos , Indústria de Laticínios/métodos , Europa (Continente) , Países Baixos , União Europeia , Bem-Estar do Animal
2.
Acta Paediatr ; 88(4): 431-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10342544

RESUMO

The aims of the study are to analyse Swedish trends in overweight and obesity-as measured by body mass index (BMI)-between 1971 and 1995, and to examine socioeconomic and geographic differences between groups of individuals on the basis of information on 18-y-old military conscripts. The study population comprises all males born in 1953, 1958, 1963, 1968, and between 1973 and 1977, reported to be living in Sweden at 17 y of age according to nationwide population registers (RTPs). Utilizing the unique personal ID number, sociodemographic data in the RTPs and in Population and Housing censuses were linked to data on BMI in the national Military Service Conscription Registry for the years 1971 to 1995. These data were obtained from compulsory medical examinations held at military induction at 18 y of age. BMI data were available for 448 732 (89%) of a total of 503 689 subjects. Mean BMI increased by 6.6% over the study period-from 21.1 kg/m2 in 1971 to 22.4 kg/m2 in 1995. Unadjusted trend analyses showed a 2.4 times increase in the prevalence of overweight among 18-y-old males over the period-from 6.9% in 1971 to 16.3% in 1995. Over the same years, the prevalence of obesity increased 3.5 times-from 0.9% to 3.2%. After adjustment for muscle power, demographic factors, and living area, the prevalence of overweight was found to have increased 1.4 times, and obesity 1.7 times between 1971 and 1993. The prevalence of overweight was considerably higher among 18-y-old males from low-educated families than among those from high-educated families in both 1971 and 1995. The prevalence of overweight was also found to be higher in both 1971 and 1995 among young men from rural and/or sparsely populated areas than among those living in Sweden's largest cities. Mean BMI, and the prevalence of overweight and obesity have increased among 18-y-old males in Sweden over the last 24 y. The increased risk of overweight among young men from low-educated families and those from rural and/or sparsely populated areas detected in 1971 was still evident in 1995.


Assuntos
Obesidade/epidemiologia , Adolescente , Índice de Massa Corporal , Escolaridade , Humanos , Masculino , Crescimento Demográfico , Prevalência , Fatores Socioeconômicos , Suécia
3.
J Med Chem ; 40(18): 2831-42, 1997 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-9288165

RESUMO

A number of 3-isoxazolol bioisosteres, 7a-i, of (S)-glutamic acid (Glu), in which the methyl group of (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA, 1) was replaced by different 5-membered heterocyclic rings, were synthesized. Comparative in vitro pharmacological studies on this series of AMPA analogues were performed using receptor binding assays (IC50 values) and the electrophysiological rat cortical slice model (EC50 values). None of these compounds showed detectable affinity for the N-methyl-D-aspartic acid subtype of Glu receptors. Some of the compounds were weak inhibitors of [3H]kainic acid binding. The inhibitory effects on [3H]AMPA binding and agonist potencies at AMPA receptors of 7a-i were strictly dependent on the structure, electrostatic potential, and methyl substitution of the heterocyclic 5-substituent. Thus, while 7a (IC50 = 0.094 microM; EC50 = 2.3 microM) was approximately equipotent with AMPA (IC50 = 0.023 microM; EC50 = 5.4 microM), (RS)-2-amino-3-[3-hydroxy-5-(1H-imidazol-2-yl)isoxazol-4-yl]propio nic acid (7b) (IC50 = 48 microM; EC50 = 550 microM) was some 2 orders of magnitude weaker than AMPA, and (RS)-2-amino-3-[3-hydroxy-5-(1-methyl-1H-imidazol-2-yl)-isoxazol-4 -yl] propionic acid (7c) (IC50 > 100 microM; EC50 > 1000 microM) was inactive. Furthermore, (RS)-2-amino-3-[3-hydroxy-5-(2-methyl-2H-tetrazol-5-yl)isoxazol -4-yl] propionic acid (7i) (IC50 = 0.030 microM; EC50 = 0.92 microM) was more potent than AMPA, whereas its N-1 methyl isomer, (RS)-2-amino-3-[3-hydroxy-5-(1-methyl-1H-tetrazol-5-yl)isoxazol -4-yl] propionic acid (7h) (IC50 = 54 microM; EC50 > 1000 microM) was inactive as an AMPA agonist. A quantitative structure-activity relationship (QSAR) analysis revealed a positive correlation between receptor affinity, electrostatic potential near the nitrogen atom at the "ortho" position of the heterocyclic 5-substituent, and the rotational energy barrier around the bond connecting the two rings. We envisage that a hydrogen bond between the protonated amino group and an ortho-positioned heteroatom of the ring substituent at the 5-position stabilize receptor-active conformations of these AMPA analogues.


Assuntos
Córtex Cerebral/fisiologia , Corpo Caloso/fisiologia , Isoxazóis/síntese química , Isoxazóis/farmacologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/análogos & derivados , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/síntese química , Animais , Ligação Competitiva , Córtex Cerebral/efeitos dos fármacos , Corpo Caloso/efeitos dos fármacos , Eletrofisiologia , Potenciais Evocados/efeitos dos fármacos , Técnicas In Vitro , Isoxazóis/química , Ácido Caínico/metabolismo , Cinética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Potenciometria , Ratos , Receptores de AMPA/efeitos dos fármacos , Receptores de AMPA/metabolismo , Receptores de Ácido Caínico/efeitos dos fármacos , Receptores de Ácido Caínico/metabolismo , Relação Estrutura-Atividade , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/química , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
4.
J Med Chem ; 38(22): 4380-92, 1995 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-7473566

RESUMO

A study of the effect of aromatic substitution on D1 and D2 affinity in a series of previously reported trans-1-piperazino-3-phenylindans shows similar structure-activity relationships for the two receptor sites. 6-Substituted derivatives have affinity for both receptors, and 6-chloro-or 6-fluoro-substituted derivatives show preference for D1 receptors. D1 affinity and selectivity are significantly increased in a series of new piperazine ring substituted derivatives. Potent D1 and D2 antagonism in vivo are confined to derivatives with relatively small substituents in the 2-position of the piperazine ring (e.g. 2-methyl,2,2-dimethyl, 2-spirocyclobutyl or 2-spirocyclopentyl). Consequently, the effect of aromatic substitution is examined in a series of 1-(2,2-dimethylpiperazino)-3-arylindans. All these compounds except the 4-, 5-, 7- and 4'-chloro-substituted derivatives have potent D1 affinity (IC50's below 10 nM) and the majority of the compounds antagonize SK&F 38393-induced circling in 6-OHDA-lesioned rats with ED50 values about 1 mumol/kg. In vitro all compounds show preference for D1 receptors, but in vivo they are equally effective as D1 and D2 antagonists. The compounds have high affinity for 5-HT2 receptors and selected compounds show high affinity for alpha 1 adrenoceptors. Furthermore, a subgroup consisting of (-)-38, (-)-39, (-)-41, and (-)-54 does not induce catalepsy in rats. These compounds have the potential of being "atypical" antipsychotics and have consequently been selected for further studies. The non-receptor-blocking enantiomers are shown to be inhibitors of DA and NE uptake in accordance with previous observations in compounds unsubstituted in the piperazine ring. Two compounds, (+)-38 and (+)-40, block DA uptake with IC50 values below 10 nM. Finally, the observed structure-activity relationships are discussed in relation to previously published pharmacophore models for D2 and 5-HT2 receptors. It is concluded that the piperazine substituents might induce a different binding mode at the dopamine receptor sites, perhaps only at the D1 receptor site.


Assuntos
Antipsicóticos/farmacologia , Antagonistas de Dopamina/farmacologia , Indanos/farmacologia , Piperazinas/farmacologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Células 3T3 , Adrenérgicos/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1 , Animais , Antipsicóticos/síntese química , Antagonistas de Dopamina/síntese química , Antagonistas de Dopamina/química , Antagonistas dos Receptores de Dopamina D2 , Indanos/síntese química , Indanos/química , Camundongos , Oxidopamina/antagonistas & inibidores , Oxidopamina/farmacologia , Piperazinas/síntese química , Piperazinas/química , Ratos , Receptores Adrenérgicos alfa 1/metabolismo , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Antagonistas da Serotonina/química , Antagonistas da Serotonina/farmacologia , Relação Estrutura-Atividade
5.
Comp Biochem Physiol Comp Physiol ; 103(1): 199-204, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1356697

RESUMO

1. The fatty acid composition of the triglyceride fraction of mink milk sampled during mid-lactation (day 28 post partum) from two nursing mink was compared to that of plasma samples and to the fatty acid composition of the feed rations used. 2. Chemical analysis of the triglyceride composition of mink milk demonstrated only minute concentrations of fatty acids with a chain length below C14. 3. The saturated C16:0- and C18:0-unit fatty acids in mink milk made up for 24-40% of the total amount of fatty acids extracted, the remainder being represented by mono and polyunsaturated long-chain (C16-C24) fatty acids. 4. Preliminary in vitro experiments proved the incorporation of 14C-labelled glucose, acetate or palmitate into triacylglycerols in cultures of mink mammary tissue to be linear for at least 2 hr. 5. The in vitro capacity for de novo fatty acid synthesis in mink mammary tissue using 14C-labelled glucose or acetate was low, i.e. ranging from 0.096-0.109 nmol/g (fresh tissue)/min, and amounted to only about 5% of that obtained in the case of [14C]palmitic acid incubation. 6. Following 14C-labelled acetic or palmitic acid incubation of mink mammary tissue neither desaturation nor chain elongation was observed. 7. In response to long-term feeding on rations with two different sources of animal fat (F = fish oil or L = lard) the influence of compositional changes in dietary neutral lipids on the fatty acid composition of the lipids of mink milk is discussed.


Assuntos
Gorduras na Dieta/farmacologia , Lactação/metabolismo , Lipídeos/biossíntese , Glândulas Mamárias Animais/metabolismo , Vison/metabolismo , Animais , Ácido Graxo Sintases/metabolismo , Ácidos Graxos/sangue , Ácidos Graxos/metabolismo , Feminino , Leite/metabolismo , Triglicerídeos/química
6.
Biochem J ; 277 ( Pt 2): 341-4, 1991 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-1859362

RESUMO

The induction of acyl-CoA-binding protein (ACBP) and ACBP mRNA was investigated in 3T3-L1 cells during growth and insulin-induced differentiation. The level of ACBP relative to both total soluble protein and DNA increased during insulin-stimulated conversion of 3T3-L1 cells from preadipocytes into fully developed adipocytes. So did the total rate of lipogenesis, as measured by incorporation of [1-14C]acetate. A similar increase in ACBP mRNA relative to total RNA was observed. These results therefore suggest that ACBP plays a specific role in the lipogenic process. However, this role might be indirect, as the increase in lipogenesis preceded the increase in ACBP. The significance of this finding is discussed.


Assuntos
Tecido Adiposo/citologia , Proteínas de Transporte/biossíntese , RNA Mensageiro/biossíntese , Acetatos/metabolismo , Tecido Adiposo/fisiologia , Animais , Proteínas de Transporte/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Clonagem Molecular , Dexametasona/farmacologia , Inibidor da Ligação a Diazepam , Biblioteca Gênica , Cinética , Lipídeos/biossíntese , Fígado/metabolismo , Camundongos , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos , Fatores de Tempo
7.
Comp Biochem Physiol A Comp Physiol ; 99(1-2): 129-35, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1675944

RESUMO

1. Isolated mammary gland cells were cultured embedded in collagen gels or as monolayers on floating collagen gels. Under these conditions the cells were able to grow for at least 6 weeks during five passages. Growth was sustained in M199/F12 (1:1) supplemented with insulin, hydrocortisone, epidermal growth factor, tri-iodothyronine, estradiol and bovine serum albumin. 2. The cells secreted lactose into the medium in significant amounts throughout the culture period. 3. Prolactin had a slightly stimulatory effect as had fetal bovine serum on growth and protein synthesis, but none of these factors were obligatory in this respect. Insulin-like growth factor I (Somatomedin C) could replace high concentrations of insulin whereas bovine growth hormone had no detectable effect. 4. Depending on the hormone content of the medium and the age of the culture, different labelling patterns of the arachidonic acid-containing phospholipids were observed. The effect of prolactin on phosphatidyl inositol and arachidonic acid metabolism was studied.


Assuntos
Glândulas Mamárias Animais/fisiologia , Animais , Células Cultivadas , Feminino , Cabras , Lactalbumina/metabolismo , Lactação/fisiologia , Lactose/metabolismo , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Fosfolipídeos/metabolismo , Prolactina/farmacologia , Biossíntese de Proteínas
8.
Biochem J ; 262(2): 513-9, 1989 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-2803267

RESUMO

Acyl-CoA-binding protein (ACBP) was purified from rat liver. The Mr was determined as 9932 +/- 10 by mass spectrometry and calculated as 9937.8 from the sequence. The protein binds acyl-CoA esters (C8-C16) with high affinity, but was unable to bind fatty acids. ACBP was found mainly (86%) in the soluble fraction, and the concentration was highest in liver, 5-6 micrograms/mg of soluble protein. The complete primary structure was determined by a combination of gas-phase Edman degradations and mass spectrometry. Extensive use of 252Cf plasma-desorption mass spectrometry facilitated the identification and verification of peptides. Comparison with the previously determined sequence of bovine acyl-CoA-binding protein revealed a very strong sequence similarity (83%), and all of the differences could be accounted for by single base changes.


Assuntos
Proteínas de Transporte/isolamento & purificação , Proteínas de Neoplasias , Proteínas do Tecido Nervoso , Acil Coenzima A/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Transporte/análise , Proteínas de Transporte/metabolismo , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Ácidos Graxos/metabolismo , Fígado/análise , Dados de Sequência Molecular , Ratos
9.
J Dairy Sci ; 70(7): 1344-9, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3624590

RESUMO

Dispersed epithelial cells from lactating bovine and goat mammary glands incorporated acetate into all fatty acids (C4 to C16) that were incorporated into mainly triacylglycerols. The cells secreted free fatty acids only into the incubation medium, and this secretion was dependent on the concentration of albumin and the type and amount of exogenous fatty acid added to the medium. Addition of palmitic acid to the incubation medium stimulated synthesis and incorporation of fatty acids synthesized de novo into triacylglycerols, whereas stearic and linoleic acid were inhibitory.


Assuntos
Acetatos/metabolismo , Ácidos Graxos/metabolismo , Lipídeos/biossíntese , Glândulas Mamárias Animais/metabolismo , Animais , Bovinos , Células Epiteliais , Esterificação , Feminino , Cabras , Técnicas In Vitro , Glândulas Mamárias Animais/citologia
10.
J Dairy Sci ; 70(7): 1350-4, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3624591

RESUMO

We investigated the effect of exogenously added fatty acids on de novo synthesis of individual fatty acids and their incorporation into triacylglycerols by dispersed lactating ruminant mammary gland epithelial cells. Palmitate addition strongly stimulated synthesis and incorporation of butyrate and, to a smaller extent, palmitate synthesis and incorporation. Oleic acid strongly inhibited synthesis of all fatty acids except butyrate, whereas the effect of lauric acid was nearly neutral. Free fatty acid depletion of the mammary gland cells potentiated the effect of palmitate and made oleate less inhibitory.


Assuntos
Ácidos Graxos/biossíntese , Lauratos/farmacologia , Ácidos Láuricos/farmacologia , Glândulas Mamárias Animais/metabolismo , Ácidos Oleicos/farmacologia , Palmitatos/farmacologia , Ácidos Palmíticos/farmacologia , Animais , Bovinos , Células Epiteliais , Feminino , Cabras , Técnicas In Vitro , Lipídeos/biossíntese , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos
11.
Biochem J ; 241(1): 189-92, 1987 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-3566708

RESUMO

Bovine liver was shown to contain a hitherto undescribed medium-chain acyl-CoA-binding protein. The protein co-purifies with fatty-acid-binding proteins, but was, unlike these proteins, unable to bind fatty acids. The protein induced synthesis of medium-chain acyl-CoA esters on incubation with goat mammary-gland fatty acid synthetase. The possible function of the protein is discussed.


Assuntos
Proteínas de Transporte/metabolismo , Ácidos Graxos/biossíntese , Fígado/metabolismo , Proteínas de Neoplasias , Animais , Proteínas de Transporte/farmacologia , Bovinos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Ácido Graxo Sintases/metabolismo , Proteínas de Ligação a Ácido Graxo , Feminino , Cabras , Focalização Isoelétrica , Lactação/metabolismo , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/enzimologia , Gravidez
12.
Biochem J ; 238(1): 173-6, 1986 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3800931

RESUMO

Both subcellular fractions of lactating goat mammary gland and dispersed lactating goat mammary-gland cells were able to incorporate [U-3H]2-O-hexadecylglycerol into monoalkyl-monoacylglycerol. However, the incorporation of [U-3H]2-O-hexadecylglycerol into monoalkyl-monoacylglycerol by dispersed cells was not accompanied by incorporation of fatty acid synthesized de novo or added radiolabelled fatty acid. The result therefore shows that an active monoacylglycerol pathway does not exist in goat mammary gland.


Assuntos
Glicerídeos/metabolismo , Lactação/metabolismo , Glândulas Mamárias Animais/metabolismo , Triglicerídeos/biossíntese , Acetatos/metabolismo , Ácido Acético , Animais , Feminino , Glicerol/metabolismo , Cabras , Glândulas Mamárias Animais/citologia , Ácido Palmítico , Ácidos Palmíticos/metabolismo , Gravidez , Frações Subcelulares/metabolismo
13.
Biochem J ; 238(1): 167-72, 1986 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3800930

RESUMO

The method now described for preparation of dispersed lactating goat mammary-gland cells gives a high yield of morphologically and functionally normal mammary cells. The cells synthesize specific goat milk fatty acids in the right proportions, and they respond to hormones by increased protein synthesis. The cells can be frozen and thawed without losing the above properties, which makes them an excellent tool for metabolic and hormonal studies.


Assuntos
Ácidos Graxos/metabolismo , Lactação/metabolismo , Glândulas Mamárias Animais/metabolismo , Proteínas do Leite/biossíntese , Leite/metabolismo , Acetatos/metabolismo , Ácido Acético , Animais , Separação Celular , Células Epiteliais , Epitélio/metabolismo , Feminino , Cabras , Metabolismo dos Lipídeos , Glândulas Mamárias Animais/citologia , Microscopia Eletrônica , Gravidez
16.
Biochem J ; 220(2): 513-9, 1984 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-6547605

RESUMO

Goat mammary-gland microsomal fraction by itself induces synthesis of medium-chain-length fatty acids by goat mammary fatty acid synthetase and incorporates short- and medium-chain fatty acids into triacylglycerol. Addition of ATP in the absence or presence of Mg2+ totally inhibits triacylglycerol synthesis from short- and medium-chain fatty acids, and severely inhibits synthesis de novo of medium-chain fatty acids. The inhibition by ATP of fatty acid synthesis and triacylglycerol synthesis de novo can be relieved by glycerol 3-phosphate. The effect of ATP could not be mimicked by the non-hydrolysable ATP analogue, adenosine 5'-[beta,gamma-methylene]triphosphate and could not be shown to be caused by inhibition of the diacylglycerol acyltransferase by a phosphorylation reaction. Possible explanations for the mechanism of the inhibition by ATP are discussed, and a hypothetical model for its action is outlined.


Assuntos
Ácidos Graxos/biossíntese , Glândulas Mamárias Animais/metabolismo , Triglicerídeos/biossíntese , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Esterificação , Ácido Graxo Sintases/metabolismo , Feminino , Glicerofosfatos/farmacologia , Cabras , Técnicas In Vitro , Lactação , Magnésio/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Gravidez
17.
Biochem J ; 220(2): 521-7, 1984 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-6743284

RESUMO

ATP alone had no effect on incorporation of fatty acids synthesized de novo and membrane-bound diacylglycerol into triacylglycerol. Combined addition of ATP and Mg2+ totally inhibits incorporation of fatty acids synthesized de novo and stimulated incorporation of membrane-bound diacylglycerol. ATP, Mg2+ and glycerol 3-phosphate stimulate incorporation of fatty acids synthesized de novo into triacylglycerol, but inhibited the incorporation of membrane-bound diacylglycerol. Diacylglycerol generated in situ was shown to be superior to diacylglycerols preloaded on the membrane as substrate for the diacylglycerol acyltransferase. A model is proposed to explain the effect of absorbed exogenous fatty acid on fatty acid synthesis de novo in goat mammary gland.


Assuntos
Ácidos Graxos/biossíntese , Glândulas Mamárias Animais/metabolismo , Triglicerídeos/biossíntese , Aciltransferases/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Diacilglicerol O-Aciltransferase , Diglicerídeos/metabolismo , Esterificação , Feminino , Glicerofosfatos/farmacologia , Cabras , Técnicas In Vitro , Magnésio/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Palmitoil Coenzima A/farmacologia , Gravidez
18.
Demography ; 18(2): 231-44, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7227587

RESUMO

This paper reports the outcome of an exercise in curve fitting to annual sets of Danish age-specific fertility rates for the years 1962 to 1971 by means of least squares. Functions fitted were a cubic spline, the Hadwiger and Coale-Trussell functions, the gamma and beta densities, two versions of a polynomial, and two of Brass's relational procedures, as well as the Gompertz curve. The spline function fitted all curves far better than any of the others. The Coale-Trussell procedure and gamma density were about equal, followed by the Hadwiger function. All of these functions fit the data wells. One of the polynomials fit reasonably well, but the rest of the functions were less accurate.


Assuntos
Fertilidade , Adolescente , Adulto , Fatores Etários , Dinamarca , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Estatística como Assunto
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