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1.
Lupus ; 28(1): 133-136, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30486727

RESUMEN

Toxoplasma is a common parasite worldwide that mainly affects the brain, lungs and eyes. Although toxoplasmic encephalitis is a lethal disease without treatment, past case reports show most patients with systemic lupus erythematosus who developed toxoplasmic encephalitis were misdiagnosed and treated as neuropsychiatric systemic lupus erythematosus, which led to unfavorable outcomes. We herein describe a case of disseminated toxoplasmosis affecting all the above organs with atypical symptoms, which developed with exacerbation of systemic lupus erythematosus. She had initially manifested with retinochoroiditis without vitritis, mild cognitive impairment and an isolated lung mass. These are completely different from the classic symptoms of toxoplasmosis that have been reported in patients with HIV infection and/or those after hematopoietic transplantation. Our case, together with previously reported cases, suggests the manifestation of toxoplasmosis that develops in systemic lupus erythematosus patients can be different from that seen in conventional cases and varies between individual patients. Our case highlights both the difficulty in and the importance of diagnosing toxoplasmosis in patients with systemic lupus erythematosus and provides helpful information to identify this rare, devastating, yet treatable disease.


Asunto(s)
Lupus Eritematoso Sistémico/complicaciones , Infecciones Oportunistas/complicaciones , Toxoplasmosis Cerebral/complicaciones , Toxoplasmosis Cerebral/diagnóstico , Adulto , Encéfalo/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Pulmón/diagnóstico por imagen , Vasculitis por Lupus del Sistema Nervioso Central/complicaciones , Imagen por Resonancia Magnética , Oftalmoscopios , Tomografía Computarizada por Rayos X
2.
Plant Biol (Stuttg) ; 11 Suppl 1: 94-100, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19778373

RESUMEN

Snow depth is one of the most important determinants of vegetation, especially in mountainous regions. In such regions, snow depth tends to be low at wind-exposed sites such as ridges, where stand height and productivity are limited by stressful environmental conditions during winter. Siberian dwarf pine (Pinus pumila Regel) is a dominant species in mountainous regions of Japan. We hypothesized that P. pumila produces needles with greater mass per area at wind-exposed sites than at wind-protected sites because it invests more nitrogen (N) in cell walls at the expense of N investment in the photosynthetic apparatus, resulting in increased photosynthetic N use efficiency (PNUE). Contrary to our hypothesis, plants at wind-exposed site invested less resources in needles, as exhibited by lower biomass, N, Rubisco and cell wall mass per unit area, and had higher photosynthetic capacity, higher PNUE and shorter needle life-span than plants at a wind-protected site. N partitioning was not significantly different between sites. These results suggest that P. pumila at wind-exposed sites produces needles at low cost with high productivity to compensate for a short leaf life-span, which may be imposed by wind stress when needles appear above the snow surface in winter.


Asunto(s)
Pinus/anatomía & histología , Pinus/metabolismo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Viento , Modelos Biológicos , Nitrógeno/metabolismo , Fotosíntesis/fisiología , Pinus/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrollo
3.
J Nucl Med ; 42(10): 1551-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11585872

RESUMEN

UNLABELLED: Although FDG uptake is closely related to the expression of the glucose transporter (GLUT) in malignant tumors, such a relationship has not been fully investigated in inflammatory lesions. The aim of our study was to determine the expression of GLUT subtypes in experimental inflammatory lesions and to compare the results with those in malignant tumors in relation to FDG accumulation. METHODS: Rats were inoculated with a suspension of Staphylococcus aureus or allogenic hepatoma cells (KDH-8) into the left calf muscle. Five days after S. aureus inoculation (n = 9) and 14 d after KDH-8 inoculation (n = 11), [(14)C]FDG was injected intravenously and its accumulation in the infectious and tumor tissues was determined as the percentage activity of the injected dose per gram of tissue (%ID/g). The expression of glucose transporters (GLUT-1 to GLUT-5) was investigated by immunostaining the infectious tissues (n = 6) and the tumor tissues (n = 6). Immunohistochemical grading was assessed semiquantitatively by 5 observers. RESULTS: The [(14)C]FDG uptake was significantly higher in the tumor lesion than in the inflammatory lesion (2.04 +/- 0.38 %ID/g vs. 0.72 +/- 0.15 %ID/g; P < 0.0001). The tumor and inflammatory tissues highly expressed GLUT-1 and GLUT-3. The GLUT-1 expression level was significantly higher in the tumor tissue than in the inflammatory tissue (P < 0.05). CONCLUSION: The results based on our models showed a high FDG uptake and high GLUT-1 expression level not only in the tumor lesion but also in the inflammatory lesion. The higher GLUT-1 expression level in the tumor lesion may partially explain the higher FDG accumulation in the tumor than in the inflammatory lesion.


Asunto(s)
Radioisótopos de Carbono/farmacocinética , Fluorodesoxiglucosa F18/farmacocinética , Inflamación/metabolismo , Neoplasias Hepáticas Experimentales/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Animales , Femenino , Transportador de Glucosa de Tipo 1 , Inmunohistoquímica , Trasplante de Neoplasias , Ratas , Ratas Wistar , Infecciones Estafilocócicas/metabolismo
4.
Behav Brain Res ; 89(1-2): 275-83, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9475635

RESUMEN

Using anesthetized and immobilized monkeys, responses of neurons in the posterior inferotemporal cortex to visual patterns were examined. Response properties were compared between the sulcus and the gyrus, extending between the anterior tip of the posterior middle temporal sulcus and the inferior occipital sulcus. Of 682 neurons tested, 37% in the sulcus (134/365) and 36% in the gyrus (113/317) responded to one or more patterns. The preference of neurons for patterns varied from neuron to neuron; some neurons responded selectively to one particular pattern, whereas others responded to two or more patterns. To evaluate response properties of neurons, two indices were calculated (the pattern preference index and the pattern selectivity index). The distributions of these indices in the sulcus did not differ significantly from those of the gyrus. Furthermore, the relationship between the pattern preference index and the pattern selectivity index for each neuron was almost the same in these two portions; most neurons responding to a small number of patterns showed inhibitory or weak responses to the worst pattern. In both portions, most neurons had receptive fields with small eccentricities and receptive field sizes were almost the same. These results suggest that the cortex in the sulcus in the posterior inferotemporal cortex is involved in the detection of features of visual patterns, similarly to the cortex in the gyrus.


Asunto(s)
Neuronas/fisiología , Reconocimiento Visual de Modelos/fisiología , Lóbulo Temporal/fisiología , Animales , Electrodos Implantados , Electrofisiología , Macaca , Estimulación Luminosa , Lóbulo Temporal/anatomía & histología , Lóbulo Temporal/citología , Campos Visuales/fisiología
5.
Behav Brain Res ; 96(1-2): 101-13, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9821547

RESUMEN

Using anesthetized and immobilized monkeys, this study investigated the representation of the visual field in the superior temporal sulcus in the posterior inferotemporal cortex. Of 1043 neurons in the posterior inferotemporal cortex including the sulcus and the gyrus, and surrounding areas that were tested, 540 (52%) responded to visual stimuli and their receptive fields were mapped. In the ventral bank of the superior temporal sulcus at the level corresponding to the posterior middle temporal sulcus, the foveal visual fields, which were dominant, were represented ventrally and the parafoveal visual fields dorsally. The upper and lower visual fields were represented intermingledly and no segregation between the representation of the upper and lower visual fields was seen. In the lateral convexity of the gyrus, the foveal visual fields were represented dorsally and the peripheral visual fields ventrally with the foveal visual fields being predominant. The upper visual fields were represented posteriorly, however locations and sizes of the representation of the upper and lower visual fields varied between hemispheres. The receptive field sizes of neurons in the sulcus were almost the same as those in the gyrus, and these receptive field sizes were intermediate between those of anterior inferotemporal neurons and V4 neurons. These findings suggest that the cortex in the sulcus in the posterior inferotemporal cortex is involved in the central vision, similarly to the cortex in the gyrus.


Asunto(s)
Lóbulo Temporal/fisiología , Campos Visuales/fisiología , Animales , Mapeo Encefálico , Lateralidad Funcional/fisiología , Macaca , Neuronas/fisiología , Estimulación Luminosa , Lóbulo Temporal/citología
6.
Behav Brain Res ; 100(1-2): 67-76, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10212054

RESUMEN

Neuronal activities were recorded in areas TEO and TE of the inferotemporal cortex in four hemispheres of two monkeys during the performance of a visual pattern discrimination task. Tolerances of responses to patterns against changing stimulus size and orientation, and deleting patterns halves were investigated and compared between TEO and TE neurons. Of 311 neurons tested, 80 (26%) responded to one or more patterns out of four standard patterns. Of these 80 neurons, 50 (63%) were recorded in area TEO and 30 (38%) in area TE. Neurons responsive to patterns were recorded in both areas TEO and TE, however degrees of tolerance of responses were different between TEO and TE neurons. Tolerances of TEO neurons were moderate and degrees of tolerance varied from neuron to neuron. Responses to particular patterns were dependent on stimulus size, stimulus orientation, and/or completeness of patterns. By contrast, tolerances of TE neurons were generally strong. Responses to particular patterns were not affected by changing stimulus size, changing stimulus orientation nor deleting patterns halves. These results suggest that area TEO rather than area TE is involved in detecting and processing particular visual shapes.


Asunto(s)
Atención/fisiología , Orientación/fisiología , Reconocimiento Visual de Modelos/fisiología , Percepción del Tamaño/fisiología , Transmisión Sináptica/fisiología , Lóbulo Temporal/fisiología , Animales , Aprendizaje Discriminativo/fisiología , Dominancia Cerebral/fisiología , Macaca , Masculino , Recuerdo Mental/fisiología , Neuronas/fisiología
7.
Brain Res ; 410(1): 121-4, 1987 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-3580890

RESUMEN

Responsiveness of single inferotemporal (IT) neurons to a tone as a start or warning signal in each test trial was investigated in monkeys performing visual discrimination of 4 patterns. It was found that the same IT neurons were responsive to both auditory signal and visual discriminanda with different response characteristics from each other. The activity of IT neurons for the auditory signal in the visual discrimination paradigm reflects an engagement process in attention to the visual discriminanda.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Aprendizaje Discriminativo/fisiología , Lóbulo Temporal/fisiología , Animales , Mapeo Encefálico , Macaca , Reconocimiento Visual de Modelos/fisiología , Psicoacústica
8.
Oecologia ; 113(3): 314-324, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28307815

RESUMEN

We studied the effects of photon flux density (PFD) and leaf position, a measure of developmental age, on the distribution of nitrogen content per unit leaf area (N area) in plants of different heights, in dense stands grown at two nitrogen availabilities and in solitary plants of the erect dicotyledonous herb Xanthium canadense. Taller more dominant plants received higher PFD levels and experienced a larger difference in relative PFD between their youngest and oldest leaves than shorter subordinate plants in the stands. Differences in PFD between leaves of solitary plants were assumed to be minimal and differences in leaf traits, found for these plants, could thus be mainly attributed to an effect of leaf position. In the solitary plants, N area decreased with leaf position while in the plants from the stands it decreased with decreasing relative PFD, indicating both factors to be important in determining the distribution of N area. Due to the effect of leaf position on N area, leaves of subordinate plants had a higher N area than older leaves of dominant plants which were at the same height or slightly higher in the canopy. Consequently, the N area distribution patterns of individual plants plotted as a function of relative PFD were steeper, and probably closer to the optimal distribution which maximizes photosynthesis, than the average distribution in the stand. Leaves of subordinate plants had a lower mass per unit area (LMA) than those of dominant plants. In the dominant plants, LMA decreased with decreasing relative PFD (and with leaf position) while in the subordinate plants it increased. This surprising result for the subordinate plants can be explained by the fact that, during the course of a growing season, these plants became increasingly shaded and newer leaves were thus formed at progressively lower light availability. This indicates that LMA was strongly determined by the relative PFD at leaf formation and to a lesser extent by the current PFD. Leaf N content per unit mass (N mass) was strongly determined by leaf position independent of relative PFD. This indicates that N mass is strongly ontogenetically related to the leaf-aging process while changes in N area, in response to PFD, were regulated through changes in LMA.

9.
Nucl Med Commun ; 23(6): 545-50, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12029209

RESUMEN

The expression of glucose transporters (GLUTs) and its relationship to fluorodeoxyglucose accumulation in malignant tumours have been well investigated, while such a relation has not been studied in inflammatory lesions. The aim of the present study was to investigate the effects of insulin and glucose loading on the expression of GLUTs in inflammatory lesions and compare them with those in malignant tumours in relation to fluorodeoxyglucose accumulation. All tissue specimens used in this study were obtained in our previous study, in which rats were inoculated with allogenic hepatoma cells (KDH-8), Staphylococcus aureus, or turpentine oil into the left calf muscle and divided into three subgroups: insulin loaded, glucose loaded, and control groups. The expression of glucose transporters (GLUT-1 to GLUT-5) was investigated by immunostaining the lesions (n=5-6, for each group). In all control groups, the expression levels of GLUT-1 and GLUT-3 were significantly higher than those of GLUT-2, GLUT-4 and GLUT-5. Insulin loading did not significantly affect the expression levels of GLUT-1 and GLUT-3 in these lesions except for a significant but slight decrease in the GLUT-1 expression level in the inflammatory lesion of non-infectious origin (89% of the control value). Glucose loading significantly decreased the expression level of GLUT-1 in the inflammatory lesion of non-infectious origin (70% of the control value, P<0.01), and that of GLUT-3 in the inflammatory lesion of infectious origin (70% of the control value, P<0.05), while the expression levels of GLUT-1 and GLUT-3 in the tumour were not significantly affected. These results demonstrate the effects of insulin and glucose loading on the expression level of a molecule (GLUT proteins). The decreased GLUT-1 and GLUT-3 expression levels induced by glucose loading may partly explain the impaired FDG uptake observed in our previous study.


Asunto(s)
Fluorodesoxiglucosa F18/farmacocinética , Glucosa/metabolismo , Insulina/metabolismo , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Neoplasias Hepáticas Experimentales/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Animales , Glucosa/farmacología , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/metabolismo , Inflamación/diagnóstico por imagen , Inflamación/metabolismo , Insulina/farmacología , Masculino , Proteínas de Transporte de Monosacáridos/clasificación , Conejos , Cintigrafía , Radiofármacos/farmacocinética , Ratas , Ratas Wistar , Sensibilidad y Especificidad , Infecciones Estafilocócicas/diagnóstico por imagen , Infecciones Estafilocócicas/metabolismo
10.
Jpn J Antibiot ; 38(10): 2735-69, 1985 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-3908727

RESUMEN

To objectively evaluated the usefulness of the standard formulation of cefaclor (CCL) and the long-acting formulation of cefaclor (S6472) in noncatheterized complicated urinary tract infection (UTI), a double-blind comparison study was carried out using cephalexin (CEX) as a control. Patients were orally treated with either 500 mg of CCL 3 times/day, 750 mg of S6472 2 times/day, or 500 mg of CEX 4 times/day for 14 days. Overall clinical effect was evaluated on days 5 and 14 in accordance with the UTI therapeutic evaluation standard, with check for recurrence on day 21. There was no demographic difference between the groups. There was no difference in the effective rate on day 5 among the 3 treatment groups: 58.1% in S6472 group, 66.0% in CCL group and 61.9% in CEX group. Nor on day 14, was there any significant difference in the effective rate among the 3 groups: 70.8% in S6472 group, 63.4% in CCL group and 61.8% in CEX group. Stratification analyses (by UTI group, infection site, in- or out-patient, time of starting treatment, pretreatment severity of pyuria, total number of bacteria before treatment) revealed no significant difference among the 3 groups. Therapeutic effect evaluated by physicians in charge was not significantly different among the 3 groups on day 5 or day 14. In terms of overall therapeutic effect, all 3 products were very effective in patients infected with sensitive bacteria: On day 5, 85.4% in S6472 group, 84.4% in CCL group, and 83.7% in CEX group. There was no significant difference among the 3 groups on either day. The incidence of side effects was not significantly different among the 3 groups: 4 out of 129 patients treated with S6472 (3.1%), 2 of 131 treated with CCL (1.5%) and 2 of 128 with CEX (1.6%). Clinical laboratory tests revealed 4 abnormal findings in 4 patients treated with S6472, 6 findings in 4 treated with CCL, and 4 findings in 2 treated with CEX, showing no significant difference in incidence among the 3 groups. Both side effects and abnormal clinical laboratory findings were mild and reversible. Physicians in charge judged the usefulness of the 3 drugs on days 5 and 14, taking efficacy and safety into consideration. Significant difference was not observed. The presence of recurrence was examined 7 days after drug withdrawal in patients regarded as remarkable responders to 14-day treatment by overall therapeutic effect evaluation.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Cefaclor/uso terapéutico , Cefalexina/análogos & derivados , Cefalexina/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Anciano , Cefaclor/administración & dosificación , Cefalexina/administración & dosificación , Ensayos Clínicos como Asunto , Preparaciones de Acción Retardada , Método Doble Ciego , Farmacorresistencia Microbiana , Femenino , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad
11.
Jpn J Antibiot ; 30(11): 928-39, 1977 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-201786

RESUMEN

A comparative study was made by the double-blind technique in order to make clear the usefulness of pivmecillinam in the treatment of intractable complicated urinary-tract infections using amoxicillin as a reference drug. Pivmecillinam was given in dosage of 400 mg (potency) per day which was one-fifth the dose of amoxicillin 2,000 mg (potency) per day. In global judgement, pivmecillinam was found superior to amoxicillin. It showed a "significant" superiority over amoxicillin for the treatment of, among others, the urinary-tract infections after prostatectomy, which are intractable diseases. When evaluated by symptoms, pivmecillinam improved bacteriuria "significantly" better than amoxicillin. When seen by causative organisms, the pivmecillinam treatment was "significantly" superior to the amoxicillin treatment against E. coli infections. Pivmecillinam was active against amoxicillin-resistant E. coli. Incidence of adverse reactions was less frequent with pivmecillinam than with amoxicillin. These results indicate that pivmecillinam is a drug of high usefulness for the treatment of intractable complicated urinary-tract infections when evaluated using amoxicillin as a reference drug.


Asunto(s)
Amdinocilina Pivoxil/uso terapéutico , Ácido Penicilánico/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Adulto , Anciano , Amdinocilina Pivoxil/efectos adversos , Amdinocilina Pivoxil/farmacología , Amoxicilina/efectos adversos , Amoxicilina/farmacología , Amoxicilina/uso terapéutico , Bacterias/efectos de los fármacos , Ensayos Clínicos como Asunto , Método Doble Ciego , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones Urinarias/complicaciones , Infecciones Urinarias/microbiología , Orina/microbiología
12.
Hinyokika Kiyo ; 30(4): 519-27, 1984 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-6385665

RESUMEN

Recurrence rate and symptoms after chemotherapy against acute uncomplicated cystitis (AUC) were studied. Upon completion of a 7-day treatment with two regimens, one of CEX alone (Group C) and the other of a combination of CEX with Lysozyme (Neuzym) (Group L), at a dose of 1 g CEX daily, efficacy of the drugs was assessed according to the criteria established by the UTI Study Group. The forty one cases in Group C and 38 cases in Group L showing an excellent response were evaluated for recurrence. The rates of recurrence were 12.2% in Group C and 21.1% in Group L during the first 7 days after treatment. In recurrent cases, bacteriuria was seen in 84.6% (11/13), pyuria in 53.8% (7/13) and miction pain in 30.8% (4/13). Thus, bacteriuria and pyuria should be the items of the criteria for AUC recurrence.


Asunto(s)
Cefalexina/uso terapéutico , Cistitis/tratamiento farmacológico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Cefalexina/administración & dosificación , Ensayos Clínicos como Asunto , Cistitis/microbiología , Femenino , Humanos , Persona de Mediana Edad , Muramidasa/administración & dosificación , Recurrencia
18.
Oecologia ; 155(4): 665-75, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18193288

RESUMEN

Some shade leaves increase their photosynthetic capacity (P (max)) when exposed to a higher irradiance. The increase in P (max) is associated with an increase in chloroplast size or number. To accommodate those chloroplasts, plants need to make thick leaves in advance. We studied the cost and benefit of photosynthetic acclimation in mature leaves of a tree species, Kalopanax pictus Nakai, in a cool-temperate deciduous forest. Costs were evaluated as the additional investment in biomass required to make thick leaves, while the benefit was evaluated as an increase in photosynthetic carbon gain. We created gaps by felling canopy trees and examined the photosynthetic responses of mature leaves of the understorey seedlings. In the shade, leaves of K. pictus had vacant spaces that were not filled by chloroplasts in the mesophyll cells facing the intercellular space. When those leaves were exposed to higher irradiance after gap formation, the area of the mesophyll surface covered by chloroplasts increased by 17% and P (max) by 27%. This increase in P (max) led to an 11% increase in daily carbon gain, which was greater than the amount of biomass additionally invested to construct thicker leaves. We conclude that the capacity of a plant to acclimate to light (photosynthetic acclimation) would contribute to rapid growth in response to gap formation.


Asunto(s)
Aclimatación/fisiología , Aclimatación/efectos de la radiación , Kalopanax/metabolismo , Kalopanax/efectos de la radiación , Fotosíntesis/efectos de la radiación , Plantones/efectos de la radiación , Luz Solar , Biomasa , Carbono/metabolismo , Simulación por Computador , Kalopanax/crecimiento & desarrollo , Modelos Biológicos , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Plantones/metabolismo , Factores de Tiempo
19.
Eur J Neurosci ; 25(8): 2523-35, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17445248

RESUMEN

The lateral prefrontal cortex (LPFC) is important for working memory (WM) task performance. Neuropsychological and neurophysiological studies in monkeys suggest that the lateral prefrontal cortex is functionally segregated based on the working memory domain (spatial vs. non-spatial). However, this is not supported by most human neuroimaging studies, and the discrepancy might be due to differences in methods and/or species (monkey neuropsychology/physiology vs. human neuroimaging). We used positron emission topography to examine the functional segregation of the lateral prefrontal cortex of Japanese macaques (Macaca fuscata) that showed near 100% accuracy on spatial and non-spatial working memory tasks. Compared with activity during the non-working memory control tasks, the dorsolateral prefrontal cortex (DLPFC) was more active during the non-spatial, but not during the spatial, working memory task, although a muscimol microinjection into the dorsolateral prefrontal cortex significantly impaired the performance of both working memory tasks. A direct comparison of the brain activity between the two working memory tasks revealed no differences within the lateral prefrontal cortex, whereas the premotor area was more active during the spatial working memory task. Comparing the delay-specific activity, which did not include task-associated stimulus/response-related activity, revealed more spatial working memory-related activity in the posterior parietal and premotor areas, and more non-spatial working memory-related activity in the dorsolateral prefrontal cortex and hippocampus. These results suggest that working memory in the monkey brain is segregated based on domain, not within the lateral prefrontal cortex but rather between the posterior parietal-premotor areas and the dorsolateral prefrontal-hippocampus areas.


Asunto(s)
Corteza Cerebral/fisiología , Memoria/fisiología , Animales , Conducta Animal/fisiología , Corteza Cerebral/anatomía & histología , Agonistas del GABA/metabolismo , Humanos , Macaca , Masculino , Muscimol/metabolismo , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones
20.
Oecologia ; 149(4): 571-82, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16832649

RESUMEN

The photosynthetic light acclimation of fully expanded leaves of tree seedlings in response to gap formation was studied with respect to anatomical and photosynthetic characteristics in a natural cool-temperate deciduous forest. Eight woody species of different functional groups were used; two species each from mid-successional canopy species (Kalopanax pictus and Magnolia obovata), from late-successional canopy species (Quercus crispula and Acer mono), from sub-canopy species (Acer japonicum and Fraxinus lanuginosa) and from vine species (Schizophragma hydrangeoides and Hydrangea petiolaris). The light-saturated rate of photosynthesis (Pmax) increased significantly after gap formation in six species other than vine species. Shade leaves of K. pictus, M. obovata and Q. crispula had vacant spaces along cell walls in mesophyll cells, where chloroplasts were absent. The vacant space was filled after the gap formation by increased chloroplast volume, which in turn increased Pmax. In two Acer species, an increase in the area of mesophyll cells facing the intercellular space enabled the leaves to increase Pmax after maturation. The two vine species did not significantly change their anatomical traits. Although the response and the mechanism of acclimation to light improvement varied from species to species, the increase in the area of chloroplast surface facing the intercellular space per unit leaf area accounted for most of the increase in Pmax, demonstrating the importance of leaf anatomy in increasing Pmax.


Asunto(s)
Aclimatación/fisiología , Luz , Fotosíntesis/fisiología , Hojas de la Planta/fisiología , Árboles/fisiología , Acer/fisiología , Fraxinus/fisiología , Hydrangea/fisiología , Kalopanax/fisiología , Magnolia/fisiología , Hojas de la Planta/anatomía & histología , Quercus/fisiología , Plantones/fisiología
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