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1.
Science ; 360(6384): 58-62, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29622648

RESUMEN

Nitrogen availability is a pivotal control on terrestrial carbon sequestration and global climate change. Historical and contemporary views assume that nitrogen enters Earth's land-surface ecosystems from the atmosphere. Here we demonstrate that bedrock is a nitrogen source that rivals atmospheric nitrogen inputs across major sectors of the global terrestrial environment. Evidence drawn from the planet's nitrogen balance, geochemical proxies, and our spatial weathering model reveal that ~19 to 31 teragrams of nitrogen are mobilized from near-surface rocks annually. About 11 to 18 teragrams of this nitrogen are chemically weathered in situ, thereby increasing the unmanaged (preindustrial) terrestrial nitrogen balance from 8 to 26%. These findings provide a global perspective to reconcile Earth's nitrogen budget, with implications for nutrient-driven controls over the terrestrial carbon sink.

2.
J Hydrol Eng ; 22(1)2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32801609

RESUMEN

A common phenomenon observed in natural and constructed wetlands is short-circuiting of flow and formation of stagnant zones that are only indirectly connected with the incoming water. Biogeochemistry of passive areas is potentially much different than that of active zones. In the research reported in this paper, the spatial resolution of a previously developed wetland nutrient cycling model was improved in order to capture the spatial variability of concentrations and reaction rates regarding nitrogen and carbon cycles throughout active and passive zones of wetlands. The upgraded model allows for several compartments in the horizontal domain, with all neighboring compartments connected through advective and dispersive/diffusive mass transport. The model was applied to data collected from a restored wetland in California that was characterized by the formation of a large stagnant zone at the southern end of the wetland due to close vicinity of the inlet and outlet structures in the northern end. Mass balance analysis revealed that over the course of the research period, about 23.4±3.9% of the incoming total nitrogen load was removed or retained by the wetland. It was observed that mass of all exchanges (physical and biogeochemical) regarding nitrogen cycling decreased along the activity gradient from active to passive zones. Model results also revealed that anaerobic processes become more significant along the activity gradient towards passive areas.

3.
J Cosmet Sci ; 60(2): 205-15, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19450421

RESUMEN

Coloring hair using a level 3 permanent colorant involves two processes, lightening the underlying melanin and information of the colored chromophores inside the hair. In a typical in-market products the oxidant used to achieve these changes is hydrogen peroxide buffered at pH 10 with an alkalizer such as ammonium hydroxide. A new oxidant has been developed based on the combination of ammonium carbonate, hydrogen peroxide and glycine at pH 9 that can match the lightening and color performance of the current oxidant. It has the advantage that both the carbonate and hydrogen peroxide concentrations can be changed to alter the lightening performance making it a more flexible oxidant. This allows the capability to lighten the hair in a shorter time, or with lower hydrogen peroxide levels. This paper discusses the key oxidizing species that are present in both systems and the mechanisms of melanin lightening. In addition, the lightening performance will be assessed as a function of time, pH, hydrogen peroxide concentration and carbonate concentration. The importance of glycine to the oxidant is also described along with a proposal for its mechanism of action. It has been demonstrated that the addition of glycine can control the undesired formation of carbonate radicals that can be generated from the oxidant. The control of these radicals enables the oxidant to deliver excellent lightening with no negatives in fiber damage bs. conventional oxidants.


Asunto(s)
Tinturas para el Cabello/farmacología , Cabello/efectos de los fármacos , Oxidantes/farmacología , Carbonatos/farmacología , Cabello/química , Humanos , Peróxido de Hidrógeno/farmacología , Espectroscopía de Resonancia Magnética
4.
J Environ Qual ; 37(5): 1837-46, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18689745

RESUMEN

Wetlands can improve water quality through natural processes including sedimentation, nutrient transformations, and microbial and plant uptake. Tailwater from irrigated pastures may contribute to nonpoint source water pollution in the form of sediments, nutrients, and pathogens that degrade downstream water quality. We examined benefits to water quality provided by a natural, flow-through wetland and a degraded, channelized wetland situated within the flood-irrigation agricultural landscape of the Sierra Nevada foothills of Northern California. The non-degraded, reference wetland significantly improved water quality by reducing loads of total suspended sediments, nitrate, and Escherichia coli on average by 77, 60, and 68%, respectively. Retention of total N, total P, and soluble reactive P (SRP) was between 35 and 42% of loads entering the reference wetland. Retention of pollutant loads by the channelized wetland was significantly lower than by the reference wetland for all pollutants except SRP. A net export of sediment and nitrate was observed from the channelized wetland. Decreased irrigation inflow rates significantly improved retention efficiencies for nitrate, E. coli, and sediments in the reference wetland. We suggest that maintenance of these natural wetlands and regulation of inflow rates can be important aspects of a best management plan to improve water quality as water runs off of irrigated pastures.


Asunto(s)
Escherichia coli/fisiología , Sedimentos Geológicos , Microbiología del Agua , Contaminantes del Agua/química , Agua/química , Humedales , Agricultura , Bromuros/química , Monitoreo del Ambiente , Nitratos/química , Nitrógeno/química , Fosfatos/química
5.
J Cosmet Sci ; 58(4): 319-27, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17728932

RESUMEN

High Pressure Differential Scanning Calorimetry (HPDSC) can be used to gain information on both the degree of crystallinity in the intermediate filaments (IFs) and the structural rigidity of the surrounding matrix or intermediate filament associated proteins (IFAP) of the hair cortex. We have used HPDSC to measure changes in denaturation temperature (T(D)) and enthalpy (deltaH(D)) of the crystalline components after treatment with bleach products. Literature reports suggest that a decrease in peak denaturation temperature is indicative of permanent damage to the hair. However, changing the rigidity of the matrix surrounding the IFs, by temporarily changing electrostatic interactions, should also result in a similar decrease in peak temperature. The complex nature of bleach formulations including oxidants, alkalizers and salts suggests that several of the components could have a non-permanent affect on salt bridges and hydrogen bonds and hence rigidity or viscosity of the matrix. We have compared the denaturation temperature with levels of lightening (dL) and tensile properties of the fiber after treatment both before and after removal of actives from the fiber. It is evident that the HPDSC results are strongly influenced by formulation components and that these changes are reversible with extensive washing or dialysis. Combined with tensile data, it is proposed that a decrease in T(D) and deltaH(D) following treatment with bleach products can be due to both permanent and reversible changes to either the intermediate filaments or intermediate filament associated proteins of the hair fiber.


Asunto(s)
Preparaciones para el Cabello/química , Cabello/química , Desnaturalización Proteica/efectos de los fármacos , Rastreo Diferencial de Calorimetría , Humanos , Resistencia a la Tracción
6.
Chemosphere ; 69(4): 585-94, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17459453

RESUMEN

Evaporation basins (or ponds) are the most commonly used facilities for disposal of selenium-laden saline agricultural drainage in the closed hydrologic basin portion of the San Joaquin Valley, California. However concerns remain for potential risk from selenium (Se) toxicity to water fowl in these evaporation basins. In this study, we examined the chemical status of Se in both waters and sediments in two currently operating evaporation pond facilities in the Tulare Lake Drainage District. Some of the saline ponds have been colonized by brine-shrimp (Artemia), which have been harvested since 2001. We evaluated Se concentration and speciation, including selenate [Se(VI)], selenite [Se(IV)], and organic Se [org-Se or Se(-II)] in waters and sediment extracts, and fractionation (soluble, adsorbed, organic matter (OM)-associated, and Se(0) and other resistant forms) in sediments and organic-rich surface detrital layers from the decay of algal blooms. Selenium in ponds without vascular plants exhibited similar behavior to wetlands with vascular plant present, indicating that similar Se transformation processes and mechanisms had resulted in Se immobilization and an increase of reduced Se species [Se(IV), org-Se, and Se(0)] from Se(VI)-dominated input waters. Selenium concentrations in most pond waters were significantly lower than the influent drainage water. This decrease of dissolved Se concentration was accompanied by the increase of reduced Se species. Selenium accumulated preferentially in sediments of the initial pond cell receiving drainage water. Brine-shrimp harvesting activities did not affect Se speciation but may have reduced Se accumulation in surface detrital and sediments.


Asunto(s)
Agricultura , Compuestos de Selenio/análisis , Selenio/análisis , Selenito de Sodio/análisis , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis , Adsorción , Animales , Acuicultura , Artemia , Sedimentos Geológicos/análisis , Ácido Selénico
7.
Water Sci Technol ; 55(3): 55-61, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17410840

RESUMEN

The efficacy of using constructed wetlands (CWs) to sequester organic carbon and nutrients from irrigation tailwaters was studied in the San Joaquin Valley, California. Two CWs were monitored during the 2004 irrigation season, a new CW (W-1) and 10-year-old CW (W-2). Input/output waters from CW were collected weekly and analyzed for a variety of water quality contaminants. Organic carbon, nutrient and sediment retention efficiencies were evaluated from input/output concentrations. Characteristics of sediment were examined spatially at W-2. Results indicate that W-2 was more efficient at contaminant removal. Average particulate organic carbon retention, was 70+/-13% (mean +/-standard deviation) in W-2 and 48+/-32% in W-1. Chlorophyll-a, a measure of algal biomass, was higher at W-1, especially in input waters. Initially, output concentration of chlorophyll-a increased 15-fold in W-2, however over time, as emergent vegetation established, chlorophyll-a decreased to 35% of input levels. Average total N removal efficiency was 45 +/-18% for W-2 compared to 22 +/-32% in W-1. Total P removal efficiency was 72+/-14% at W-2 compared to 18+/-26% at W-1. CWs were most effective at removing total suspended solids, 84 +/-15% and 97+/-2% for W-1 and W-2, respectively. Results demonstrate that CWs are effective at capturing POC, sediment and nutrients from irrigation tailwaters.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Contaminación del Agua/prevención & control , Humedales , California , Monitoreo del Ambiente/métodos , Geografía , Reproducibilidad de los Resultados , Irrigación Terapéutica/efectos adversos , Movimientos del Agua
8.
J Cosmet Sci ; 58(6): 621-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18305875

RESUMEN

High-pressure differential scanning calorimetry (HPDSC) can be used to gain information on both the degree of crystallinity in the intermediate filaments (IFs) and the structural rigidity of the surrounding matrix or intermediate filament associated proteins (IFAP) of the hair cortex (1-3). We have used HPDSC to measure changes in the denaturation temperature (T(D)) and enthalpy (DeltaH(D)) of the crystalline components after multiple treatments with permanent hair colorant products. We have observed that after three repeat treatments both the denaturation enthalpy and peak temperature are significantly decreased vs the untreated starting substrate. However, on dialysis of the fibers in deionized water this decrease is shown to be completely reversible, returning the enthalpy and temperature to that of the untreated hair. It is proposed that the decrease is due to the incorporation of formulation components such as the alkalizer and surfactants etc. and metal ions such as calcium and magnesium from the tap wash water. These components are predicted to have a non-permanent effect on the salt bridges and hydrogen bonds and hence the rigidity or viscosity of the matrix. We have compared the denaturation temperature with the tensile properties of the fiber after treatment both before and after removal of actives from the fiber.


Asunto(s)
Tinturas para el Cabello/química , Cabello/química , Rastreo Diferencial de Calorimetría , Humanos , Desnaturalización Proteica , Resistencia a la Tracción , Termodinámica
9.
Artículo en Inglés | MEDLINE | ID: mdl-17271557

RESUMEN

The results of medical specialist consultations sampled from several rural clinics located throughout India indicate that remote expert opinions can improve the speed and accuracy of diagnosis. Central to this presentation is a description of how real-time and store & forward telemedicine services can be provided to rural populations over hybrid networks made up of ISDN, POTS, VSAT, cellular, and Cable Internet connections. A model for meeting the specialized medical needs of developing countries will be highlighted. Descriptions, examples, and benefits of how Browser-based client-server architectures are being used in over 20 locations in India and Mexico for triaging real-time vital signs, DICOM images, audio & video, and clinical text information will be highlighted.

10.
J Chem Ecol ; 29(3): 703-30, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12757329

RESUMEN

Tannins influence ecosystem function by affecting decomposition rates, nutrient cycling, and herbivory. To determine the role of tannins in ecological processes, it is important to quantify their abundance and understand how structural properties affect reactivity. In this study, purified tannins from the foliage of nine species growing in the pygmy forest of the northern California coast were examined for chemical reactivity, protein precipitation capacity (PPC), and structural characteristics (13C NMR). Reactivity of purified tannins varied among species 1.5-fold for the Folin total phenol assay, and 7-fold and 3-fold, respectively, for the acid butanol and vanillin condensed tannin assays. There was about a 5-fold difference in PPC. Variation in chemical reactivity and PPC can be largely explained by differences in structural characteristics of the tannins determined by 13C NMR. In particular, the condensed versus hydrolyzable tannin content, as well as the hydroxylation pattern of the B-ring and stereochemistry at the C-2-C-3 position appear to influence reactivity. Due to the large differences in chemical reactivity among species, it is necessary to use a well-characterized purified tannin from the species of interest to convert assay values to concentrations. Our results suggest that structural characteristics of tannins play an important role in regulating their reactivity in ecological processes.


Asunto(s)
Proteínas de Plantas/química , Taninos/química , Árboles , Animales , Precipitación Química , Ecosistema , Espectroscopía de Resonancia Magnética , Hojas de la Planta , Relación Estructura-Actividad
11.
Fresenius J Anal Chem ; 369(3-4): 206-11, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11293695

RESUMEN

Quantitative analysis of signaling molecules from single cells and cellular materials requires careful validation of the analytical methods. Strategies have been investigated that enable single neurons and neuronal tissues to be stored before being assayed for many low-weight, biologically active molecules, such as serotonin, dopamine, and citrulline. Both metacerebral cell and pedal ganglia homogenates isolated from Pleiuohbrain-Chae californica have been studied by capillary electrophoresis with two complimentary laser-induced fluorescence detection methods. For homogenized ganglia samples, several cellular analytes (such as arginine and citrulline) are unaffected by standing at room temperature for days. Many other analytes in the biological matrix, including the catecholamines and indolamines, degrade by 20% within 10 h at room temperature. Rapidly freezing samples or preserving them with ascorbic acid preserves more than 80% of the dopamine and about 70% of the serotonin even after five days. In addition, serotonin and dopamine remain completely stable for at least five days by combining the ascorbic acid preservation and freezing at -20 degrees C. The timing of preservation is critical in maintaining the original composition of the biological samples. Using our optimum storage protocol of freezing the sample within 2 h after isolation, we can store frozen homogenate ganglia samples for more than four weeks before assay while still obtaining losses less than 10% of the original serotonin and dopamine. The nanoliter-volume single cell samples, however, must be analyzed within 4 h to obtain losses of less than 10% for serotonin related metabolites.


Asunto(s)
Ganglios de Invertebrados/química , Neuronas/química , Neurotransmisores/análisis , Animales , Dopamina/análisis , Electroforesis Capilar/métodos , Invertebrados , Serotonina/análisis , Triptófano/análisis , Tirosina/análisis
12.
Vet Pathol ; 34(1): 61-73, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9150551

RESUMEN

Cell adhesion molecules are glycoproteins expressed on the cell surface and play an important role in inflammatory as well as neoplastic diseases. There are four main groups: the integrin family, the immunoglobulin superfamily, selectins, and cadherins. The integrin family has eight subfamilies, designated as beta 1 through beta 8. The most widely studied subfamilies are beta 1 (CD29, very late activation [VLA] members), beta 2 (leukocyte integrins such as CD11a/CD18, CD11b/CD18, CD11c/CD18, and alpha d beta 2), beta 3 (CD61, cytoadhesions), and beta 7 (alpha 4 beta 7 and alpha E beta 7). The immunoglobulin superfamily includes leukocyte function antigen-2 (LFA-2 or CD2), leukocyte function antigen-3 (LFA-3 or CD58), intercellular adhesion molecules (ICAMs), vascular adhesion molecule-1 (VCAM-1), platelet-endothelial cell adhesion molecule-1 (PE-CAM-1), and mucosal addressin cell adhesion molecule-1 (MAdCAM-1). The selectin family includes E-selectin (CD62E), P-selectin (CD62P), and L-selectin (CD62L). Cadherins are major cell-cell adhesion molecules and include epithelial (E), placental (P), and neural (N) subclasses. The binding sites (ligands/receptors) are different for each of these cell adhesion molecules (e.g., ICAM binds to CD11/CD18; VCAM-1 binds to VLA-4). The specific cell adhesion molecules and their ligands that may be involved in pathologic conditions and potential therapeutic strategies by modulating the expression of these molecules will be discussed.


Asunto(s)
Moléculas de Adhesión Celular , Animales , Moléculas de Adhesión Celular/clasificación , Moléculas de Adhesión Celular/fisiología , Moléculas de Adhesión Celular/uso terapéutico , Humanos , Inmunoglobulinas/química
13.
J Occup Environ Med ; 38(5): 507-14, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8733642

RESUMEN

Several topical treatments for hydrofluoric acid dermal burns (Zephiran, calcium acetate and magnesium hydroxide antacid soaks, and calcium gluconate gel) were assessed for efficacy in a pig model. Gross appearance and histopathology of treated and untreated burn sites were evaluated. For superficial burns, Zephiran was most effective; calcium acetate, magnesium hydroxide antacid, and calcium gluconate gel were less effective. For deep burns, gross observations showed that calcium acetate and Zephiran were most efficacious, whereas histopathology indicated comparable efficacy of Zephiran, calcium acetate, and calcium gluconate gel for all skin layers. Magnesium hydroxide antacid demonstrated efficacy only for the subdermis. The clinically beneficial effects of both Zephiran and calcium gluconate gel were affirmed. Although results suggest that calcium acetate and magnesium-containing antacids may be beneficial for human hydrofluoric acid dermal burns, these are not established clinical treatments.


Asunto(s)
Acetatos/administración & dosificación , Antiácidos/administración & dosificación , Compuestos de Benzalconio/administración & dosificación , Quemaduras Químicas/tratamiento farmacológico , Gluconato de Calcio/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Ácido Fluorhídrico , Hidróxido de Magnesio/administración & dosificación , Ácido Acético , Administración Tópica , Animales , Quemaduras Químicas/patología , Modelos Animales de Enfermedad , Masculino , Porcinos , Factores de Tiempo , Resultado del Tratamiento
14.
Contemp Top Lab Anim Sci ; 35(1): 79-80, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16457528
15.
Fundam Appl Toxicol ; 25(1): 1-8, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7601318

RESUMEN

The antihistamine, pyrilamine maleate, was fed for up to 2 years to groups of 57 Fischer 344 (F344) rats of each sex at dietary levels of 0, 300, 1500, or 3000 ppm (free base). Eight or nine of these rats per sex and dose group were killed at 65 weeks to analyze hematology and clinical chemistry in all groups and histopathology of control and high-dose animals. Histopathology also was performed on all dead or moribund rats and on all that survived for 2 years. Average daily exposures were 11 to 150 mg/kg pyrilamine compared to human dosages up to 3 mg/kg. Pyrilamine treatment did not reduce survival. Final body weights were reduced relative to controls (mid-dose males, 93%, females, 82%: high-dose males, 82%, females, 70%). The incidences of inflammation of the nasolacrimal duct (chronic in females; suppurative in males), liver cytoplasmic vacuolization (males), and the combination of animals with either liver basophilic or clear cell foci (males) tended to significantly increase with dose. Adrenal pheochromocytomas, mammary gland fibroadenomas, and neoplasms of the clitoral gland, thyroid c-cell, and pituitary gland all tended to decrease with increasing dose in females. In males only preputial gland neoplasms exhibited a similar negative trend. While two ovarian granulosatheca cell benign tumors occurred in high-dose females, these were thought to be a random occurrence. There was no evidence for the carcinogenicity of pyrilamine in F344 rats in the current study.


Asunto(s)
Carcinógenos/toxicidad , Pirilamina/toxicidad , Médula Suprarrenal/efectos de los fármacos , Médula Suprarrenal/patología , Animales , Peso Corporal/efectos de los fármacos , Pruebas de Carcinogenicidad , Ingestión de Alimentos/efectos de los fármacos , Neoplasias de las Glándulas Endocrinas/inducido químicamente , Femenino , Masculino , Conducto Nasolagrimal/efectos de los fármacos , Conducto Nasolagrimal/patología , Tamaño de los Órganos , Neoplasias Ováricas/inducido químicamente , Pirilamina/administración & dosificación , Ratas , Ratas Endogámicas F344 , Pruebas de Toxicidad
16.
J Occup Med ; 34(9): 902-9, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1447596

RESUMEN

There currently exist various opinions concerning the best therapy for managing hydrogen fluoride (HF) dermal burns. Previously reported animal studies designed to evaluate the efficacy of certain therapies are not completely convincing. Studies initially were conducted to develop a reliable animal model for assessing efficacy of treatment. Evaluation of several animal species, dosing regimens (HF concentrations, exposure periods), and application techniques showed that the most consistent and reproducible dermal lesions were produced with 38% HF applied to the skin of anesthetized pigs for exposures of 9, 12, or 15 minutes using Hill Top Chamber patches. Using this model, the efficacy of six clinically applicable treatments was assessed by subjectively scoring and statistically analyzing photographic and histopathological data obtained from treated and untreated control lesions. Photographic data analysis ranked treatments with respect to effectiveness as follows: iced Zephiran and 10% calcium acetate soaks--highly effective; 2.5% calcium gluconate gel, 5.0% calcium gluconate injection and iced Hyamine soaks--effective; 10% calcium gluconate injection--ineffective. Histopathological data analysis showed the topical treatments (2.5% calcium gluconate gel, iced Hyamine, or iced Zephiran soaks) to be most effective in reducing superficial epidermal damage, and the 5% calcium gluconate injection or 10% calcium acetate soaks to be beneficial to deeper tissues of the dermis and subdermis. Injection of 10% calcium gluconate was ineffective. This study suggests that the anesthetized pig model has good applicability for assessing efficacy of HF dermal burn therapies. In addition, it indicates that further experimentation with 10% calcium acetate soaks is warranted.


Asunto(s)
Quemaduras Químicas/terapia , Ácido Fluorhídrico/efectos adversos , Piel/patología , Acetatos/uso terapéutico , Ácido Acético , Animales , Compuestos de Benzalconio/uso terapéutico , Bencetonio/uso terapéutico , Quemaduras Químicas/etiología , Quemaduras Químicas/patología , Gluconato de Calcio/administración & dosificación , Gluconato de Calcio/uso terapéutico , Geles , Inyecciones , Masculino , Porcinos , Resultado del Tratamiento , Agua/uso terapéutico
17.
Mem Cognit ; 19(6): 579-92, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1758304

RESUMEN

The effect of information integration on the recall of ambiguous prose passages was investigated. In Experiment 1, subjects read ambiguous passages that were difficult to comprehend without titles. In judging the relative positions in the passages of pairs of test sentences, subjects performed better when they read passages headed by a suitable title than when they read untitled passages or received a title at the time of testing. In Experiment 2, subjects provided with a title at encoding also better discriminated complete old sentences from foils composed of fragments of two different old sentences than did subjects provided with no titles or with titles at the time of testing. These two tests index the degree of inter- and intrasentence information integration, respectively. Two findings indicated that integration affected free recall of an ambiguous passage. First, when the degree of integration of the passage's propositions was controlled, free recall of the passage was no different for subjects who did or did not know the passage's title at encoding. Second, inducing subjects to comprehend the passage's sentences individually, without relating them to one another, reduced free recall of the passage.


Asunto(s)
Atención , Formación de Concepto , Recuerdo Mental , Orientación , Lectura , Adulto , Humanos
18.
Atherosclerosis ; 64(1): 47-54, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3036172

RESUMEN

The effect of dietary fiber isolated from dehulled, defatted soybean seeds on cholesterol (CHOL) metabolism and atherosclerosis in rabbits was studied alone and in combination with isolated soy protein (ISP). Soy fiber (SF) contains both cellulosic and non-cellulosic dietary fiber. Based on the official AOAC method, soy fibers contains 75% total dietary fiber. Rabbits at 6 months of age were randomly assigned to 1 of 4 dietary treatments. All rabbits received either a casein or ISP-based diet with cellulose or SF as the only dietary fiber source for 36 weeks. Fasting blood samples and feces were collected and analyzed for lipids from individual rabbits. The entire aorta was removed and fixed, and sudanophilic stained lesions were examined visually. Rabbits consuming the SF and/or ISP diets had lower plasma CHOL levels and lower incidence of atherosclerotic lesions relative to the rabbits fed the casein-based cellulose diets. Rabbits consuming the SF and/or ISP diets also had a lower CHOL content in their liver and heart. Rabbits fed ISP-based diets had consistently increased fecal bile acid excretion, whereas rabbits fed diets containing SF had increased fecal and cholesterol concentration. These results suggest a complementary role for SF and ISP in preventing atherosclerosis in rabbits.


Asunto(s)
Arteriosclerosis/etiología , Colesterol/metabolismo , Fibras de la Dieta/farmacología , Proteínas en la Dieta/farmacología , Glycine max , Animales , Ácidos y Sales Biliares/orina , Colesterol/sangre , Heces/análisis , Hígado/metabolismo , Masculino , Miocardio/metabolismo , Conejos
19.
Am J Vet Res ; 47(3): 587-93, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3083733

RESUMEN

Fifty-three bovine and 7 ovine carcasses condemned for having eosinophilic myositis were evaluated. Four (7.3%) of the bovine carcasses had a few, large local lesions in skeletal muscles (category A), and 49 (92.7%) of the bovine carcasses and 7 (100%) of the ovine carcasses had multiple, small, disseminated lesions in tongue, esophagus, heart, diaphragm, or skeletal muscles (category B). Tissue from carcasses of category B were evaluated for bacteria, viruses, selenium, and pathologic changes. Pathogenic bacteria and viruses were not isolated and selenium concentrations were normal. In category B, all carcasses had granulomas; of the 49 bovine carcasses and 7 ovine carcasses, 38 (77.6%) and 7 (100%), respectively, had one or more granulomas with opened dead sarcocysts. The data indicated that opened sarcocysts killed the host myocyte and adjacent myocytes and stroma, thereby initiating granuloma formation.


Asunto(s)
Enfermedades de los Bovinos/patología , Enfermedades Musculares/veterinaria , Miositis/veterinaria , Sarcocistosis/veterinaria , Enfermedades de las Ovejas/patología , Animales , Bovinos , Eosinófilos/citología , Granuloma/patología , Granuloma/veterinaria , Ventrículos Cardíacos/patología , Enfermedades Musculares/patología , Miocardio/patología , Miositis/patología , Sarcocistosis/patología , Ovinos
20.
J Am Vet Med Assoc ; 187(4): 425-6, 1985 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-2993213

RESUMEN

Severe hypoglycemia associated with a metastatic pancreatic beta-cell carcinoma was found in an adult female American Eskimo dog. Metastatic tumor was found in the renal glomeruli as opposed to the more common hepatic metastatic site.


Asunto(s)
Adenoma de Células de los Islotes Pancreáticos/veterinaria , Enfermedades de los Perros/patología , Insulinoma/veterinaria , Neoplasias Renales/veterinaria , Neoplasias Pancreáticas/veterinaria , Animales , Perros , Femenino , Insulinoma/patología , Insulinoma/secundario , Glomérulos Renales/patología , Neoplasias Renales/secundario , Páncreas/patología , Neoplasias Pancreáticas/patología
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