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1.
Science ; 193(4257): 1003-5, 1976 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-17735702

RESUMO

Field-grown pearl millet (Pennisetum americanum) and guinea grass (Panicum maximum), lightly fertilized and inoculated with Spirillum lipoferum, produced significantly higher yields of dry matter than did uninoculated controls. Up to 42 and 39 kilograms of nitrogen per hectare were replaced by inoculation for pearl millet and guinea grass, respectively. The data demonstrate that nitrogen fixation by these grass-Spirillum systems is efficient and is achieved at a reasonable energy cost to the plant.

2.
Int J Gynecol Cancer ; 18(2): 262-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17587320

RESUMO

Central nervous system metastasis from gynecological malignancy is a rare phenomenon that has been described in the past 30 years. The objective of this study is to analyze the treatment modalities and prognostic factors for brain metastases from gynecological tumors that predict prolonged survival. A retrospective chart and pathology review of 47 patients diagnosed with a gynecological tumor with brain metastasis in 1994-2004 was performed. Thirty patients had undergone initial diagnosis and treatment at our institution, and 17 patients were referred following primary treatment at an outside institution. Adjusted Chi-square, Kaplan-Meier survival estimates, log-rank tests, and Cox regression analysis were utilized for statistical analysis of the total cohort. Of the 3146 patients with newly diagnosed gynecological cancer in this 10-year period, 30 developed brain metastasis demonstrating an incidence of 0.95%. Overall median survival from the time of diagnosis of brain metastasis was 7.5 months (95% CI 4-15, range 9 days-64 months) and 40% survival at 1 year. Multivariate analysis revealed evidence of extracranial disease at time of metastasis diagnosis predicted decreased survival (hazard ratio 6.207), while papillary serous histology (hazard ratio 0.42), and use of any chemotherapy (hazard ratio 0.24) predicted longer survival. No other patient or tumor characteristics were found to be independent prognostic indicators affecting survival. Despite the ominous prognosis associated with the development of brain metastasis, these retrospective data suggest that multimodal therapy with whole brain radiation therapy, chemotherapy, and surgical resection of metastases in selected patients without evidence of extracranial and with solitary or multiple lesions can prolong survival.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias dos Genitais Femininos/mortalidade , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Terapia Combinada , Feminino , Neoplasias dos Genitais Femininos/patologia , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
3.
Res Vet Sci ; 82(3): 349-57, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17113116

RESUMO

The objective of this study was to determine the effect of a monensin controlled-release capsule administered intraruminally at drying-off on body condition score (BCS) at calving, milk yield, fertility and concentration of energy-related blood metabolites in Holstein cows dried-off with low BCS (< or = 3.0, scale 1 to 5 with a 0.25 point of increment). Between July and August, 2001, 220 cows from parity 2 or more and dried-off 50-70 days before expected parturition, with a BCS < or = 3.0 were randomly assigned to either a treatment group (n=110; oral capsule of monensin releasing 335 mg/day for 95 days) or a control group (no capsule, n=110). At assignment, on day 21 before expected parturition, at calving, and at 7, 14, and 21 days in milk a blood sample was obtained from a random sub sample of 10 cows per group. Effects of monensin on serum NEFA, BHBA and glucose were measured. Milk yield, milk fat and protein content (%) at DHIA test days during the entire lactation, 305 ME milk production and reproductive responses were compared. Monensin significantly improved BCS at calving, increased milk yield at test days 4 and 8, decreased the percentage of milk protein, did not change the percentage of milk fat, and decreased NEFA and BHBA during the post-partum period.


Assuntos
Bovinos/fisiologia , Ionóforos/farmacologia , Lactação/efeitos dos fármacos , Monensin/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Constituição Corporal , Dieta/veterinária , Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Feminino , Lactação/fisiologia , Leite/química , Monensin/administração & dosagem , Parto , Gravidez , Fatores de Tempo
4.
Prev Vet Med ; 73(1): 33-42, 2006 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-16202461

RESUMO

The objective of this study was to determine the effect of a monensin controlled-release capsule on the proportion of cows with subclinical ketosis (SK). During July to August 2001, 300 cows dried-off 50-70 days before expected parturition were randomly assigned to either a treatment (n = 150, oral capsule, 335 mg/d of monesin for 95 d) or control group (no capsule, n = 150). At 14 days postpartum, a milk sample was obtained and evaluated for beta-hydroxybutyrate (BHBA) using a semi-quantitative ketone test strip. In a sub-sample of 50 cows per group a blood sample was taken and analyzed for BHBA using an ELISA kit. Milk BHBA > or = 200 micromol/L was used as the cut-off value for diagnosis of SK. The incidence of SK based on the milk test was statistically different between groups (P < or = 0.05) with a value of 26.6% for control and 14.5% for cows treated with monensin, respectively. Cows treated with monensin were 0.68 times less likely to give a positive result for milk BHBA than non-treated cows (0.53-0.80; 95% CI). Serum BHBA concentrations did not differ between groups (0.81 +/- 0.09 mmol/L versus 0.70 +/- 0.07 mmol/L for controls and treated, respectively; P > 0.05). However, for each incremental increase in serum BHBA of 0.1 mmol/L occurrence of SK increased 52% (OR = 1.52; 1.21-1.91; 95% CI).


Assuntos
Doenças dos Bovinos/prevenção & controle , Ionóforos/administração & dosagem , Cetose/veterinária , Monensin/administração & dosagem , Ácido 3-Hidroxibutírico/sangue , Ácido 3-Hidroxibutírico/metabolismo , Administração Oral , Animais , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/metabolismo , Preparações de Ação Retardada , Feminino , Cetose/sangue , Cetose/metabolismo , Cetose/prevenção & controle , Lactação , Modelos Lineares , Leite/química , Gravidez , Fitas Reagentes
5.
Poult Sci ; 85(5): 947-54, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16673777

RESUMO

Two sources of methionine (Met) activity are frequently used in commercial feed formulation: DL-2-hydroxy-4-(methylthio) butanoic acid (HMTBA), most commonly available as an 88% solution with 12% water; and DL-methionine (DLM, 99% powder). Despite the fact that both compounds have been in commercial use for over 50 yr, controversy and confusion remain with respect to their relative bioefficacy (RBE). This paper presents a review of the use of a nonlinear common plateau asymptotic regression technique (NLCPAR) that has been used to compare the 2 Met sources with particular emphasis on the validity of the basic assumptions of that model. The thesis of this paper is that the controversy is due, at least in part, to the misapplication of this regression technique to estimate the RBE of HMTBA and DLM. The NLCPAR model is a bioassay with the key dependent assumptions that HMTBA is a dilution of DLM, and that each follows dose-response curves of the same form and approach a common plateau. Because both provide Met activity, it may be considered reasonable to accept these assumptions; however, specifically testing them demonstrated that the assumption of a common dose-response is not supported by data. The common plateau assumption was tested with an alternative approach of fitting nonlinear separate plateaus asymptotic regression (NLSPAR) to a set of 13 published broiler studies in which the NLCPAR model had been used to estimate RBE of HMTBA and DLM. The hypothesis of a common plateau was rejected (P < 0.01), meaning that the conclusion that HMTBA had lower bioefficacy than DLM based on the NLCPAR methodology was not valid. An example using published data demonstrated that the NLSPAR model was a significantly better fit than the NLCPAR model, and showed that HMTBA and DLM followed different dose responses. Consequently, there was no single value for RBE for the entire dose range; rather, the RBE of the 2 compounds varied with use level. The evidence presented here indicates that separate plateau models should be used when comparing these 2 products. These more valid models can then be used for predictions of differences between HMTBA and DLM at levels of expected use.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Metionina/administração & dosagem , Metionina/farmacocinética , Modelos Estatísticos , Animais , Disponibilidade Biológica , Galinhas/metabolismo , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Absorção Intestinal , Valor Preditivo dos Testes , Perus/metabolismo
6.
Poult Sci ; 85(3): 476-85, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16553279

RESUMO

The effects of addition of bacitracin methylene disalicylate (BMD) or virginiamycin (VM) to a corn-soybean meal diet on broiler performance and gastrointestinal tract (GIT) growth parameters and morphology were studied at various ages during growth and finishing. Male and female birds were killed at 1, 3, 5, or 7 wk of age for gross and histologic examination of the duodenum and ileum. Feeding either antibiotic increased BW and decreased intestinal length and weight at all times compared with control birds. However, intestinal length and weight decreases were greater in birds fed VM than BMD at 1 and 3 wk of age. The only change found in the duodenum resulting from dietary treatment was an increase in the number of villi per unit length in birds given VM but not BMD or control. In the ileum, the muscularis mucosa was thinner in birds given VM than in those fed the control diet. Chicks supplemented with VM had a smaller total villus area and shorter villus height and crypt depth in the ileum than birds fed the control diet or BMD. Physical changes in the intestine of birds given either antibiotic growth promoter, although not the same, resulted in improved performance.


Assuntos
Antibacterianos/farmacologia , Bacitracina/farmacologia , Galinhas/anatomia & histologia , Galinhas/fisiologia , Intestinos/efeitos dos fármacos , Intestinos/crescimento & desenvolvimento , Virginiamicina/farmacologia , Animais , Galinhas/crescimento & desenvolvimento , Feminino , Masculino , Caracteres Sexuais
7.
Genetics ; 159(2): 869-82, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606559

RESUMO

Polyploidy has played an important role in higher plant evolution and applied plant breeding. Polyploids are commonly categorized as allopolyploids resulting from the increase of chromosome number through hybridization and subsequent chromosome doubling or autopolyploids due to chromosome doubling of the same genome. Allopolyploids undergo bivalent pairing at meiosis because only homologous chromosomes pair. For autopolyploids, however, all homologous chromosomes can pair at the same time so that multivalents and, therefore, double reductions are formed. In this article, we use a maximum-likelihood method to develop a general polyploid model for estimating gene segregation patterns from molecular markers in a full-sib family derived from an arbitrary polyploid combining meiotic behaviors of both bivalent and multivalent pairings. Two meiotic parameters, one describing the preference of homologous chromosome pairing (expressed as the preferential pairing factor) typical of allopolyploids and the other specifying the degree of double reduction of autopolyploids, are estimated. The type of molecular markers used can be fully informative vs. partially informative or dominant vs. codominant. Simulation studies show that our polyploid model is well suited to estimate the preferential pairing factor and the frequency of double reduction at meiosis, which should help to characterize gene segregation in the progeny of autopolyploids. The implications of this model for linkage mapping, population genetic studies, and polyploid classification are discussed.


Assuntos
Cruzamentos Genéticos , Modelos Genéticos , Poliploidia , Marcadores Genéticos
8.
Meat Sci ; 70(2): 279-84, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22063484

RESUMO

Aging patterns of nine muscles from the chuck and round from two quality classifications of beef: USDA Select and upper 2/3 of USDA Choice grade were determined. The following muscles were evaluated: infraspinatus, triceps brachii - lateral head, triceps brachii - long head, serratus ventralis, complexus, splenius, rhomboideus, vastus lateralis and rectus femoris. Muscles were divided into four portions, progressing from anterior to posterior or dorsal to ventral orientation to the carcass depending on muscle fiber orientation. One steak was removed from each portion and aged for 7, 14, 21, or 28 d postmortem, then Warner-Bratzler shear force (WBSF) analysis was conducted. Consistent aging recommendations can be given for all muscles studied, as there was no aging by muscle interaction. An aging by USDA grade interaction was noted (P<0.05). The upper 2/3 of USDA Choice need not be aged beyond 7 d. USDA Select should be aged at least 14 d. Steak location within muscle had an effect (P<0.05) on WBSF values in four muscles. These data indicate that fabrication and merchandizing decisions should be made on an individual muscle basis.

9.
Endocrinology ; 145(8): 3850-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15142989

RESUMO

Leptin and leukemia inhibitory factor (LIF) have been implicated as important mediators of implantation. The present study was designed to investigate whether leptin can directly regulate the expression of LIF and its receptor (LIF-R) in human endometrial cells and/or whether leptin-induced effects are linked to, or regulated in part by IL-1 signaling. Primary endometrial cells and endometrial epithelial cell lines (HES and Ishikawa cells) were cultured for 24-48 h in a medium containing insulin (5 microg/ml) and leptin (3, 10, and 62 nm) or IL-1beta (0.6, 3, and 10 nm) in the presence or absence of cytokines and/or receptor antagonists. The endpoints included phosphorylation of signal transducer and activator of transcription 3 (STAT3) and the relative levels of LIF, LIF-R, IL-1beta, IL-1 receptor antagonist (IL-1Ra) and IL-1 receptor type I (IL-1R tI) as determined by ELISA or Western blotting techniques. Leptin treatment increases the level of phosphorylated STAT3, LIF-R, and LIF. Leptin also increases the levels of IL-1 ligand, receptor, and antagonist as was previously reported. Blockade of OB-R with antibodies or with a specific OB-R inhibitor (leptin peptide antagonist-2) abrogated leptin-induced effects, suggesting that leptin binding to its receptor activates Janus kinase 2/STAT3 signaling. Treatment of endometrial cells with IL-1beta also results in elevated levels of LIF-R. Interestingly, the inhibition of IL-1R tI with a specific antibody or with IL-1Ra negatively affects both leptin-induced and IL-1-induced effects on LIF-R levels. Abnormal endometrial LIF expression has been associated with human infertility and leptin has profound effects on the levels of LIF, IL-1, and their cognate receptors in vitro. Thus, it is tempting to speculate that leptin's role in vivo could include the regulation of other key cytokines to be fundamental to endometrial receptivity during implantation (i.e. LIF and IL-1).


Assuntos
Endométrio/efeitos dos fármacos , Interleucina-6/análise , Leptina/farmacologia , Receptores de Citocinas/análise , Receptores de Interleucina-1/fisiologia , Células Cultivadas , Proteínas de Ligação a DNA/análise , Endométrio/química , Feminino , Humanos , Interleucina-1/análise , Fator Inibidor de Leucemia , Subunidade alfa de Receptor de Fator Inibidor de Leucemia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores para Leptina , Receptores de OSM-LIF , Fator de Transcrição STAT3 , Transdução de Sinais , Transativadores/análise
10.
J Agric Food Chem ; 47(12): 5100-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10606579

RESUMO

Precolumn derivatization applying o-phthaldialdehyde (OPA) was used to analyze free lysine, histidine, and ornithine, precursors of the respective biogenic amines cadaverine, histamine, and putrescine, which are considered indicators of fish quality and safety. This method uses 75% methanol to eliminate the use of strong acids as the extraction solution. Each analysis took 35 min, was reproducible, and allowed separation of primary amino acids in fish samples. A binary solvent delivery system coupled with a fluorescence detector and an Ultrasphere ODS column were utilized for HPLC separation. Linearity of the calibration curves was very good (r(2) = 0.99) for the amino acids of interest. Minimum concentrations of detection were 40 pmol/mL for histidine and lysine and 70 pmol/mL for ornithine. Average recoveries were 72% for lysine, 93% for histidine, and 98% for ornithine. This method used solvent gradient elution to study the levels of these analytes in mahi-mahi, bigeye tuna, and flounder.


Assuntos
Aminoácidos/análise , Peixes/metabolismo , Conservação de Alimentos , Indicadores e Reagentes/química , o-Ftalaldeído/química , Animais , Cromatografia Líquida de Alta Pressão , Linguado , Histidina/análise , Humanos , Lisina/análise , Ornitina/análise , Perciformes , Atum
11.
Arch Clin Neuropsychol ; 11(3): 215-22, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-14588925

RESUMO

The present study sought to test the hypothesis that the second factor (consisting of Failure-to-Maintain-Set and other scores) found in two recent factor analyses of the Wisconsin Card Sorting Test reflects attentional function. The effect of color overlays (an experimental manipulation known to influence neural systems linked to attention) was examined in 17 normal control and 14 attention-disordered children (ages 8 to 12). Group and Color main effects were found for Factor 1 (which consists largely of measures of perseveration) and a Color main effect was observed for Factor 2. The Color effect for Factor 2 supported the contention that this factor reflects attentional processes. A hypothesis concerning the relationship between problem solving and attention on the WCST is offered and a means for testing it is discussed.

12.
J Food Prot ; 67(10): 2255-62, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15508638

RESUMO

Biogenic amines, total volatile base-nitrogen (TVB-N), and sensory evaluation are some of the indicators used for fish quality determination. Our objective was to evaluate the relationship among histamine, cadaverine, putrescine, TVB-N, and sensory evaluation as quality assessment tools. Two groups of six mahi-mahi fillets were refrigerated at 7 degrees C and sampled on days 0, 2, 4, 6, 8, and 10. On day 3, histamine, cadaverine, and putrescine levels reached 5, 3, and 0.5 mg/100 g, respectively, whereas TVB-N reached 30 mg/100 g. Sensory scores were 6 to 6.5 (10 very fresh and 1 very spoiled) for odor, appearance, texture, and color. Correlations were 0.78 and 0.72 between histamine and cadaverine and histamine and putrescine, 0.74 and 0.80 between TVB-N and cadaverine and TVB-N and putrescine, and 0.75 and 0.78 between odor and putrescine and odor and cadaverine. AromaMaps showed distinct trends for deteriorating mahi-mahi (Coryphaena hippurus) quality.


Assuntos
Temperatura Baixa , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Alimentos Marinhos/análise , Alimentos Marinhos/normas , Animais , Aminas Biogênicas/análise , Cadaverina/análise , Peixes , Histamina/análise , Odorantes/análise , Putrescina/análise , Controle de Qualidade , Paladar , Fatores de Tempo
13.
J Parasitol ; 78(5): 822-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1403424

RESUMO

After confirming that long-term serum storage (frozen at -20 C for greater than 3 mo) causes optical density to drift upward, several modifications of an enzyme-linked immunosorbent assay (ELISA) protocol were evaluated to identify a protocol that would reduce background in porcine sera tested for trichinellosis. Modifications evaluated included blocking the antigen-coated ELISA plate with sample diluent containing 10% bovine serum albumin (BSA) or 10% nonfat milk powder (bovine lacto transfer optimizer or BLOTTO), diluting sera in sample diluent containing 10% BSA or 10% BLOTTO, and preincubating samples in sample diluent containing 10% BSA or 10% BLOTTO. Overnight preincubation (approximately 12 hr at 2 C) of fresh sera diluted (1:10) in sample diluent containing 10% BLOTTO significantly reduced background and improved the detection of experimentally infected pigs by enhancing positive-negative discrimination. When testing stored sera, the modified protocol effectively reduced the effect of storage and the kit revealed specificity of 98.4%; there was no loss in sensitivity. The effect of long-term storage at -20 C must therefore be considered when testing swine sera for trichinellosis by ELISA and possibly also when conducting other immunoglobulin assays. The modification described here may prove useful if there is no alternative to using serum stored for greater than 3 mo at -20 C.


Assuntos
Anticorpos Anti-Helmínticos/biossíntese , Ensaio de Imunoadsorção Enzimática/normas , Doenças dos Suínos/diagnóstico , Trichinella spiralis/imunologia , Triquinelose/veterinária , Animais , Anticorpos Anti-Helmínticos/sangue , Ligação Competitiva , Preservação de Sangue , Estudos de Avaliação como Assunto , Florida/epidemiologia , Técnicas Imunoenzimáticas , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina G/metabolismo , Larva/imunologia , Prevalência , Kit de Reagentes para Diagnóstico/veterinária , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/epidemiologia , Triquinelose/diagnóstico , Triquinelose/epidemiologia
14.
Theriogenology ; 60(5): 843-54, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12935862

RESUMO

The objective of this study was to determine the effect of a calcium-energy supplement at calving on the incidence of calving-related disorders (CRD), fertility, BCS and milk yield in cows fed anionic diets and to establish any associations among outcome variables. In Florida, from October to December 1997, 479 cows were assigned to three groups and treated at calving as follows: Group 1: 160 nontreated cows; Group 2: 158 cows, treated orally with 60g Ca as CaCl2; Group 3: 161 cows, treated orally with 110g Ca as calcium propionate (510g) plus propylene glycol (400g). No treatment effect was detected for any of the outcome variables. An association was found between dystocia and age and retained fetal membranes (RFM). Age and RFM were associated with metritis. RFM and displacement of the abomasum were associated with ketosis. Ketosis and age were related to displacement of the abomasum. Parity, BCS, ovarian cysts, RFM and metritis were associated with fertility.


Assuntos
Cálcio/administração & dosagem , Doenças dos Bovinos/epidemiologia , Ingestão de Energia , Fertilidade/efeitos dos fármacos , Lactação/efeitos dos fármacos , Complicações do Trabalho de Parto/veterinária , Envelhecimento , Animais , Composição Corporal , Cloreto de Cálcio/administração & dosagem , Bovinos , Suplementos Nutricionais , Distocia/epidemiologia , Distocia/veterinária , Endometrite/epidemiologia , Endometrite/veterinária , Feminino , Complicações do Trabalho de Parto/epidemiologia , Paresia Puerperal/epidemiologia , Parto , Placenta Retida/epidemiologia , Placenta Retida/veterinária , Gravidez , Propionatos/administração & dosagem , Propilenoglicol/administração & dosagem
15.
Theriogenology ; 34(3): 549-68, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16726860

RESUMO

Bull breeding soundness parameters, semen characteristics and sexual behavior were evaluated for effects on reproductive performance in single-sire beef herds. A total of 155 cow herds (Angus, 50 herds; Hereford, 40 herds; Brahman, 46 herds; and Senepol, 19 herds) bred to bulls of the same breed were observed for 8 yr. All bulls produced adequate quality semen and had scrotal circumference (SC)>or=30 cm. Reproductive performance was evaluated by the conception rate (CON), conception rate during the first 21 d of the breeding season (21dCON), mean calving date (MCD), and mean calving date of the first half of the herd to calve (HHCD). Correlations were determined between breeding soundness parameters and reproductive performance for all bulls combined, by breed, and by age. The Cp statistic was used to select models for the effects of parameters on CON, 21dCON, MCD and HHCD. Breeding season length and breed had significant effects. The percentages of normal cells, proximal droplets, detached heads and the semen score (motility plus percentage of normal cells) had a significant effect on CON when all bulls were considered. After the effect of season was deleted, the most significant parameter affecting CON in the Brahman was the percentage of detached sperm heads. In the Angus, motility was significantly correlated with all reproductive performance indices. In the Hereford, breeding soundness examination score (BSE) was positively correlated with 21dCON.

16.
J Environ Qual ; 32(1): 109-19, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12549549

RESUMO

Arsenic contamination is of concern due to its effect as a carcinogen. Understanding the distribution of arsenic in urban soils is important for establishing baseline concentrations from which anthropogenic effects can be measured. The soil cleanup target level (SCTL) for arsenic in Florida (0.8 and 3.7 mg kg(-1) in residential and commercial areas, respectively) is lower than in most states and is near the arsenic background concentrations in Florida soils. The objective of this study was to characterize the distribution of arsenic in the soils of two Florida cities, Gainesville and Miami. More than 200 soil samples were collected from three land-use classes in each city (residential, commercial, and public land), digested with USEPA Method 3051a, and analyzed with graphite furnace atomic absorption spectrophotometry. Arsenic concentrations varied greatly in Gainesville, ranging from 0.21 to approximately 660 mg kg(-1) with a geometric mean (GM) of 0.40 mg kg(-1) (after discarding outliers), which was significantly lower than the GM of 2.81 mg kg(-1) in Miami, although Miami samples ranged only from 0.32 to approximately 110 mg kg(-1). Arsenic concentrations in 29 and 4% of the Gainesville soil samples and 95 and 33% of the Miami samples exceeded the Florida residential and commercial SCTL, respectively. This study is the first to provide information on arsenic distribution in urban soils of Florida, and the data are useful for assessing arsenic contamination and determining the need for remediation.


Assuntos
Arsênio/análise , Poluentes do Solo/análise , Cidades , Monitoramento Ambiental , Poluição Ambiental/prevenção & controle , Florida , Valores de Referência
17.
J Anim Sci ; 73(4): 1164-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7628960

RESUMO

Blood samples of nine sheep were taken over time and analyzed for estrone, estradiol, and progesterone. Results were plotted for each sheep, and graphs were evaluated by 26 evaluators with various previous experience. Sheep were sampled for different time periods. Repeatabilities for the number of spikes of estrone, estradiol, and progesterone recorded for sheep were variable, ranging from .019 to .547. Repeatabilities for evaluators ranged from .033 to .427, but these values decreased to < .001 to .030 when adjusted by covariance for the number of spikes possible. Results indicated that either an objective procedure for counting spikes should be used in comparable research or that evaluators should be trained in visual counting procedures to improve their repeatability.


Assuntos
Estradiol/sangue , Estrona/sangue , Fisiologia/métodos , Progesterona/sangue , Ovinos/sangue , Animais , Reprodutibilidade dos Testes , Ovinos/fisiologia , Fatores de Tempo
18.
J Anim Sci ; 76(4): 1216-31, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9581947

RESUMO

Mixed linear models were developed by animal breeders to evaluate genetic potential of bulls. Application of mixed models has recently spread to all areas of research, spurred by availability of advanced computer software. Previously, mixed model analyses were implemented by adapting fixed-effect methods to models with random effects. This imposed limitations on applicability because the covariance structure was not modeled. This is the case with PROC GLM in the SAS System. Recent versions of the SAS System include PROC MIXED. This procedure implements random effects in the statistical model and permits modeling the covariance structure of the data. Thereby, PROC MIXED can compute efficient estimates of fixed effects and valid standard errors of the estimates. Modeling the covariance structure is especially important for analysis of repeated measures data because measurements taken close in time are potentially more highly correlated than those taken far apart in time.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos , Simulação por Computador , Modelos Estatísticos , Análise de Variância , Animais , Análise dos Mínimos Quadrados , Software , Fatores de Tempo
19.
J Anim Sci ; 66(6): 1508-19, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3397362

RESUMO

Two experiments were conducted with lambs fed concentrate-based diets to study the effects of dietary P and soil ingestion on performance, P utilization and mineral composition of serum and alimentary tract contents. In Exp. 1, 20 wether lambs were fed diets for 21 d in a 2 X 2 factorial arrangement of treatments with .2 or .3% total dietary P and O or 9% added Florida Ultisol (highly weathered soil with high P-fixation capacity) containing 4,600 and 6,400 mg/kg total Al and Fe, respectively. True P absorption increased (P less than .05) from 30 to 42% and from 37 to 54% when soil was added to the basal and high P diets, respectively. In Exp. 2, 24 wether lambs were assigned randomly to a 2 X 2 X 2 factorial arrangement of treatments. Lambs were fed during a 70-d period using diets described previously on either a restricted or an ad libitum basis. Soil increased Fe concentration in ruminal fluid (P less than .05) and ash percentage (P less than .001) in ruminal solids and feces. Aluminum concentration in ruminal solids and feces and Fe in ruminal solids were increased (P less than .001) by soil addition, whereas concentrations of Ca, Mg, P, Zn, Cu and Mn in ruminal solids and feces were decreased (P less than .01) by soil addition. There were time X P interactions on serum inorganic P (P less than .01) and Mg (P less than .05) concentrations. Although high in P-fixing capacity, soil fed to lambs in these experiments improved P utilization. Lambs appeared to be able to adapt to changes in intake of dietary minerals in soil, possibly through adaptation of ruminal microflora or a redistribution of body mineral pools.


Assuntos
Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos , Metais/metabolismo , Fósforo/farmacologia , Ovinos/metabolismo , Solo , Alumínio/metabolismo , Animais , Cálcio/sangue , Cálcio/metabolismo , Ferro/metabolismo , Magnésio/sangue , Magnésio/metabolismo , Masculino , Fósforo/metabolismo , Potássio/sangue , Potássio/metabolismo
20.
J Anim Sci ; 75(10): 2672-83, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9331869

RESUMO

The General Linear Models procedure (PROC GLM) in SAS/STAT software can be programmed to perform the standard statistical analyses used for relative bioavailability studies. The first steps are validity checks to test for statistical validity (linearity), fundamental validity (intersection of regression lines at 0 supplemental level), and equality of the basal diet mean to the point of intersection. The CLASS variable capabilities of PROC GLM can be exploited to expedite these tests. After the validity checks, the GLM procedure can be used to obtain parameter estimates for calculation of relative bioavailability. Optional output provides an inverse matrix to calculate standard errors of slopes and slope ratios. Logarithmic and other transformations of the dependent variable to reduce variance heterogeneity or achieve linearity for subsequent calculation of appropriate bioavailability values also can be accomplished within the SAS System. When nonlinear regression models are more appropriate than linear models, the NLIN procedure can be used.


Assuntos
Simulação por Computador , Cobre/farmacocinética , Dieta/veterinária , Modelos Lineares , Animais , Disponibilidade Biológica , Análise de Regressão
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