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At least 1,171 records · Page 65Linked to original sources
PubMed1984

Antibiotic distribution in normal and osteomyelitic bone.

Antibiotics are able to penetrate normal and osteomyelitic bone in a fashion that permits concentrations equivalent to those found in the serum following intravenous administration. There is no osseous barrier or gradient in osseous tissue to antibiotic penetration.

Aminoglycosides↗
PubMed1980

Effects of catecholamines on cardiovascular response and blood flow distribution to normal tissue and liver tumors in rats.

The effects of infusion of adrenaline and noradrenaline were studied in rats with intrahepatic tumors, using 99mTc-and 51Cr-labeled microspheres. The effect on general circulation, cardiac output, and tissue blood flow was pronounced, especially with infusion of noradrenaline. Studies of liver tumor perfusion in relation to surrounding liver parenchyma perfusion showed an increased tumor/liver ratio in noradrenaline-infused rats, thus indicating a preferential blood flow to the tumors induced by this drug. Adrenaline as well as 0.9% NaCl solution infusion had no effect on tumor/liver blood flow ratios. Fluorescence microscopy and monoamine determination could not reveal any noradrenaline containing nerves in the liver tumors. These experiments might suggest that the effect of intraarterial infusion with cytostatic agents might be enhanced by a simultaneously administered vasoconstrictor such as noradrenaline.

Animals↗
PubMed1993

[An analysis on the reported values of trace elements in human serum].

Statistical analysis on the data of trace element contents in human serum, published in the past 30 years, indicated the reported values for the majority of trace elements tended to decrease, even by magnitude of two orders, with the rapid development in analytical techniques and the effective control of contamination of samples during their collection, treatment and analysis. While the reported values approached their true ones, they would change to follow a normal distribution from a log normal one, with relative standard deviation and geometric deviation diminishing and, arithmetic mean approaching geometric mean. On the basis of the above results, the author presents the normal values, the best estimated normal values and the best literature values for Cu, Zn, Se, Co, Mo, Mn, Cr, Ni, As, Rb, Br, Cs, and Al.

Copper↗
PubMed1995

Bronchial hyperresponsiveness in children and adolescents.

The frequency distribution of bronchial responsiveness to both inhaled histamine and exercise both exhibit a unimodal distribution, different from a normal distribution, whereas PC20 values exhibited a lognormal distribution. BHR to both inhaled histamine (PC20 < or = 8.0 mg/ml (21 (II))) and exercise (delta % FEV1 < or = 10% (22 (III)) was found in 16% of the children and adolescents, while 6% of the population had BHR to both stimuli (22 (III)). Although a significant relationship between responsiveness to inhaled histamine and exercise existed (rs = 0.3, p < 0.001), the lack of overlap indicates that the association between the two stimuli is more complex (20 (I)). Worldwide, considerable differences in the prevalence of children with BHR to both inhaled agents and exercise have been observed. The prevalence of BHR to histamine and exercise observed in the present study was similar to findings in other industrialized countries, while the prevalence of BHR in e.g. Africa is low. All subjects with asthma had BHR to histamine and 77% had BHR to exercise, but only 35% of those with BHR to histamine (20 (I)) and 25% of those with BHR to exercise (delta FEV1 > or = 10%) (22 (III)) had symptomatic asthma. Thus low PVpos indicates that bronchial challenges are inadequate tools for screening in epidemiologic studies of asthma. The present study, however, showed that the predictive values of a negative test (PVneg) was high (100% (23 (IV) and 99% (22 (III)), respectively) supporting that bronchial challenge testing can exclude the diagnosis of asthma. Furthermore, asymptomatic subjects with BHR had reduced increase in height and lung function (FEV1) during the follow-up period of 18 months. The present observation indicate that BHR may induce permanent impairment of the lung function. The degree of responsiveness was significantly influenced by the presence of asthmatic symptoms and atopy of which house-dust mites and horse epithelium were of specific importance, whereas no association was demonstrated between BHR and recent viral infection, smoke or level of lung function. In conclusion, BHR is frequently observed in population samples and the degree of responsiveness was closely related to asthma and atopy. In children and adolescents with BHR, the increased responsiveness remained unchanged and those who developed asthma had a preexisting asymptomatic BHR.

Administration, Inhalation↗
PubMed1997

Effects of drugs on response duration differentiation. VI: differential effects under differential reinforcement of low rates of responding schedules.

The effects of methamphetamine, phencyclidine and delta9-tetrahydrocannabinol on responding under differential reinforcement of low rate schedules (DRL schedules) were studied under three different DRL time requirements. Under the DRL schedules studied, rats were required to space responses at least a minimum, but not more than a maximum, time interval apart. The time intervals between responses (interresponse times, or IRTs), when plotted as a frequency distribution, were usually a normal distribution with the peak at or near the minimum IRT required for delivery of the reinforcer. Methamphetamine flattened the IRT distribution and increased the frequency of long pauses under the DRL 1-1.3 sec schedule, but shifted the IRT distribution toward shorter IRTs under the DRL 4-5.2 and 10-13 sec schedules. Under the DRL 1-1.3 sec schedule, phencyclidine also increased long pauses. Under the DRL 4-5.2 sec and 10-13 sec schedules, phencyclidine produced dual effects on the IRT relative frequency distributions producing increases in the proportion of short IRTs similar to methamphetamine at low doses, but higher doses increased long pauses as well. delta9-Tetrahydrocannabinol had little effect on responding under the DRL 1-1.3 sec and DRL 4-5.2 sec schedules, but it greatly increased the relative frequency of short IRTs under the DRL 10-13 sec schedule. Thus the effects of drugs on responding under these DRL schedules depended on the drug, the dose and the time requirements of the schedule, which suggests that a simple description of the effects of drugs on timing behavior or time perception is inadequate.

Animals↗
PubMed1997

N-cadherin protein distribution in normal embryos and in embryos carrying mutations in the homeobox gene Hoxa-4.

N-cadherin is a calcium-dependent adhesion molecule with a potential role in a variety of morphogenetic events. Although a dynamic pattern of expression in the mouse embryo has been suggested by in situ hybridization analysis, to date there has been no report of N-cadherin protein expression. In this immunohistochemical study we surveyed N-cadherin protein expression in the mid-late gestation mouse embryo utilizing a recently characterized monoclonal antibody. We found N-cadherin expression in a wide array of tissues, including the brain, the eye, various cranial ganglia, the spinal cord, spinal ganglia, somites, vertebral and limb cartilage and perichondria, the developing lung and kidney, the enteric nervous system, and germ cells. These results suggest that N-cadherin protein expression, as in the chick embryo, correlates with the segregation of cells and with organogenesis. As cadherins have been proposed as targets of vertebrate Hox genes, we also examined N-cadherin expression in two lines of Hoxa-4 mutant mice. We did not observe any alterations in N-cadherin expression in either Hoxa-4 null embryos or in transgenic embryos that overexpress Hoxa-4 in the mesenchyme of the gut. However, the partial overlap in expression between Hox genes and N-cadherin, and the likelihood of redundancy in the regulation of target genes, leaves open the possibility that cadherins are direct or indirect targets of Hox genes during mouse embryogenesis.

Animals↗