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At least 469 records · Page 26Linked to original sources

PubMed1981

Cumulative effect of surfactants on cutaneous horny layers: lysosomal activity of human keratin layers in vivo.

Anionic surfactants have various degrees of membrane labilizing action on isolated lysosome in vitro. This action has been found to correlate with the degrees of skin roughness induced by the surfactants using the circulation method applied to the forearm of human subjects. It has been shown that the acid phosphatase activity in the human horny layer decreases during the in vivo application of the surfactants by the circulation method. The magnitude of the decrease in acid phosphatase activity has been found to correlate to the degree of skin roughness and to in vitro lysosome labilization induced by the surfactants.

Acid Phosphatase↗

PubMed2005

Influence of a fat layer on the near infrared spectra of human muscle: quantitative analysis based on two-layered Monte Carlo simulations and phantom experiments.

The influence of fat thickness on the diffuse reflectance spectra of muscle in the near infrared (NIR) region is studied by Monte Carlo simulations of a two-layer structure and with phantom experiments. A polynomial relationship was established between the fat thickness and the detected diffuse reflectance. The influence of a range of optical coefficients (absorption and reduced scattering) for fat and muscle over the known range of human physiological values was also investigated. Subject-to-subject variation in the fat optical coefficients and thickness can be ignored if the fat thickness is less than 5 mm. A method was proposed to correct the fat thickness influence.

Adipose Tissue↗

PubMed2005

Thicknesses of macular retinal layer and peripapillary retinal nerve fiber layer in patients with hyperopic anisometropic amblyopia.

This prospective study was performed to measure the macular and the peripapillary retinal nerve fiber layer (RNFL) thicknesses using optical coherence tomography (OCT) in patients with anisometropic amblyopia. Thirty-one patients with hyperopic anisometropic amblyopia were included. The macular retinal thickness and the peripapillary RNFL thickness were measured using OCT. The mean refractive error was +3.71 diopters (D) and +1.00 D, the mean macular retinal thickness was 252.5 microm and 249.7 microm, and the mean RNFL thickness was 115.2 microm and 109.6 microm, inthe amblyopic eye and the normal eye, respectively. OCT assessment of RNFL thickness revealed a significantly thicker RNFL in hyperopic anisometropic amblyopia (P=0.019), but no statistically significant difference was found in macular retinal thickness (P>0.05). In conclusion, the amblyopic process may involve the peripapillary RNFL, but not the macula. However, further evaluation is needed.

Amblyopia↗

PubMed1985

The effect of pelleting the layer ration on egg size in early-housed brown-egg-type layers.

Harco Sex-Link pullets (n = 360) were reared in cages and given a 15% protein grower ration. At 17 weeks of age, half the birds were transferred to laying cages and the photoperiod was increased to 13 hr for the first week and to 15 hr thereafter. The remaining birds were continued in the growing facility on 8 hr of light until 19 weeks when lights were increased to 13 hr daily. These birds were transferred to the laying cages at 20 weeks of age where they received 15 hr of light. At 2% production, all birds were fed a 17% protein layer diet in either a mash or pelleted form. Neither egg production nor feed efficiency was affected by age at housing or the physical form of the ration. Early-lighted pullets produced a greater percentage of small and medium-sized eggs. Egg size distribution was not affected by the physical form of the ration

Animal Feed↗

PubMed1990

The effect of 1 alpha,25-dihydroxyvitamin D3 added to a layer diet containing adequate amounts of vitamin D3 on the performance of layers.

The effect of adding 1 alpha,25-dihydroxyvitamin D3 (calcitriol) to a well-balanced, commercial layer diet containing 1,900 IU vitamin D3/kg on eggshell quality and laying performance of 56-wk-old White Leghorn hens was investigated. After 8 wk of treatment, calcitriol at 1.5 micrograms/kg diet had no discernible effect on egg weight, egg deformation, percentage shell, shell thickness, feed consumption, and egg production. At 3.0 and 4.5 micrograms/kg, feed consumption, feed production, and egg weight were significantly reduced, whereas egg deformation, percentage shell, and shell thickness were not affected. The results show that calcitriol added to a diet already adequately supplemented with vitamin D3 does not improve eggshell quality and may impair laying performance.

Animals↗

PubMed2000

[The retinal nerve fiber layer in glaucoma. II. The status of the nerve fiber layer and development of changes in the visual field. Prospective study].

PURPOSE: To determine whether retinal nerve fiber layer (RNFL) photographs can predict future glaucoma visual field damage. METHODS: In a prospective study 158 red free photographs of the RNFL were made from November 1994 to June 1995. 28 eyes of 19 patients with ocular hypertension (repeated intraocular pressure over 21 mmHg and normal visual fields--Peristat 433 Rodenstock--at first examination) could be re-examined for an average time of 42.3 (SD 4.5) months. RESULTS: Only in one eye with normal RNFL at the first examination typical glaucoma visual field defects appeared (6%), but in 6 of 12 eyes (50%) with photographically demonstrable RNFL defects. The difference was statistically significant. CONCLUSION: There is only a minor probability, that visual field defects would appear during 3-5 years in eyes with normal RNFL photographs (6%), but about 50% of eyes with originally found RNFL defects.

Adult↗

PubMed2003

Development of columnar topography in the excitatory layer 4 to layer 2/3 projection in rat barrel cortex.

The excitatory feedforward projection from layer (L) 4 to L2/3 in rat primary somatosensory (S1) cortex exhibits precise, columnar topography that is critical for columnar processing of whisker inputs. Here, we characterize the development of axonal topography in this projection using single-cell reconstructions in S1 slices. In the mature projection [postnatal day (P) 14-26], axons of L4 cells extending into L2/3 were confined almost entirely to the home barrel column, consistent with previous results. At younger ages (P8-11), however, axonal topography was significantly less columnar, with a large proportion of branches innervating neighboring barrel columns representing adjacent whisker rows. Mature topography developed from this initial state by targeted axonal growth within the home column and by growth of barrel columns themselves. Raising rats with all or a subset of whiskers plucked from P8-9, manipulations that induce reorganization of functional whisker maps and synaptic depression at L4 to L2/3 synapses, did not alter normal anatomical development of L4 to L2/3 axons. Thus, development of this projection does not require normal sensory experience after P8, and deprivation-induced reorganization of whisker maps at this age is unlikely to involve physical remodeling of L4 to L2/3 axons.

Action Potentials↗

PubMed1979

In vitro proliferation of haemopoietic cells in the presence of adherent cell layers. II. Differential effect of adherent cell layers derived from various organs.

Mouse bone marrow-derived adherent cell populations promoted proliferation of haemopoietic cells in vitro in a liquid culture system for at least 4 weeks. Adherent cell layers derived from other haemopoietic organs (foetal liver, adult spleen) and fibroblasts from embryonic tissues did not maintain haemopoietic cells in this system. Medium, conditioned by adherent cells derived from foetal liver, spleen and embryonic tissues displayed a considerable colony stimulating activity (CSA). Marrow-derived adherent cells produced no detectable CSA. A possible relationship between the in vitro expression of a growth-promoting activity of an adherent cell population on haemopoietic cells, and its endogenous CSA production, is discussed.

Animals↗

PubMed1995

[Osteoporosis prevention initiated with peripheral quantitative computerized tomography. Thin-layer and multi-layer technique].

In a representative, randomized control group of 70 healthy confirmed postmenopausal women (natural menopause for one to four years) with an average age of 52 years, it was possible to carry out a prospective study over a period of two years, during which the bone mass was investigated regularly by means of peripheral quantitative computed tomography (pQCT, Densiscan type, thin- and multi-layer technology). The distal, purely trabecular and purely compact bone mass of the radius and tibia are measured separately. The epiphyseal trabecular bone masses of the radius and tibia (262 +/- 8 mg/cm3 and 252 +/- 8 mg/cm3, respectively) are initially homogeneous, but over time they show different rates of yearly loss of bone mass: 3.0 +/- 0.4%, compared with 1.5 +/- 0.3% (means +/- SEM). Based on the bimodal frequency distribution of the annual loss rates in the core trabecular volume of the distal radius, fast losers lose more than 3.5% per year, with no significant difference between the first and the second year of observation. Women in the quintile with the highest trabecular bone mass (328 to 458 mg/cm3 at baseline) are slow losers. These women show an absolute loss of 3 mg/cm3 per year, while the women in the lowest quintile (102 to 210 mg/cm3 at baseline), with a proportion of 64% fast losers, lose an average of 10 mg/cm3, irrespective of age, number of fertile years, age at menopause and body-mass index. The bone masses in the metaphyseal compact bone remain constant.2+ a screening program before architectural changes in trabecular bone reach a critical point (i.e. in the reversible stage of osteoporosis), these women can be reliably identified within six months and monitored effectively and economically. With the general risk factors of postmenopausal osteoporosis an individual's risk of rapid bone loss cannot be predicted or determined; therefore, the precise measurement of purely trabecular bone is indispensable.

Aged↗

PubMedDate not supplied