Showing papers by "Saint Louis University published in 1973"
319 citations
TL;DR: In this paper, a detailed examination of narrow band-pass filtering shows the effect of epicentral distance and the shape of the group-velocity curve upon the filtered signal, which can be used to make accurate estimates of the spectral amplitudes of each mode.
Abstract: Narrow band-pass filtering of multi-mode surface-wave signals can be used to extract information concerning the group velocities and spectral amplitudes of each mode. A detailed examination of narrow band-pass filtering shows the effect of epicentral distance and the shape of the group-velocity curve upon the filtered signal. With this knowledge, the filtered signal can be used to make accurate estimates of the spectral amplitudes of each mode. A rectangular and a Gaussian filter are considered in detail. A numerical example is provided to indicate the values and limitations of the technique for determining the spectral amplitudes of each mode.
245 citations
244 citations
TL;DR: The components of the delayed cutaneous-hypersensitivity reaction were intact in most patients after nutritional recovery, 1-2 months later, and the impaired inflammatory reaction precluded independent evaluation of the efferent limb in vivo.
124 citations
TL;DR: Thyroid hormone content of cerebrospinal fluid pooled from euthyroid patients was studied because of its possible relationship to brain T4 and T3 levels to qualitatively resemble that in serum.
Abstract: Thyroid hormone content of cerebrospinal fluid (CSF) pooled from euthyroid patients was studied because of its possible relationship to brain T4 and T3 levels. The mean CSF total T4 level was 185 ng/100 ml, 1/40 the serum level, and the mean CSF T3 level was 17.4 ng/100 ml, 1/10 the serum level. Mean percent CSF free T4 was 3.5 and free T3 was 10.2. CSF absolute free T4 was 5.8 and absolute free T3 was 1.8 ng/100 ml, both exceeding the respective serum levels of 2.4 and 0.32 ng/100 ml. CSF TBPA bound 12.2% of T3 and 43.5% of T4, higher fractions than serum TBPA which bound 3.0% of T3 and 17.3% of T4. As estimated from maximum T4 binding capacities, the CSF TBG level was 13.2 ng/100 ml, 1/75 of the serum level, and the TBPA level was 1.47 mg/100 ml, 1/12 of the serum level. Although the total levels of T3 and T4 binding proteins were relatively small, thyroid hormone transport in CSF qualitatively resembled that in serum.
118 citations
TL;DR: A microsomal mixed function oxidase isolated from V. rosea seedlings was shown to catalyze the hydroxylation of the monoterpene alcohols, geraniol and nerol, to their corresponding 10-hydroxy derivatives as mentioned in this paper.
109 citations
TL;DR: This chapter discusses the influenza virus, which is presently available from biochemical and biophysical studies and from the electron microscopy, and attempts to design a model of the particle based on this information.
Abstract: Publisher Summary This chapter discusses the influenza virus, which is presently available from biochemical and biophysical studies and from the electron microscopy. It attempts to design a model of the particle based on this information. Although much is known about these viruses, the available information is incomplete in many respects. For example, detailed information about a specific portion of the virion or about a specific biochemical process may be available, but from one virus strain only. Attempts to formulate a detailed model are also frustrated by the limitations of the experimental procedures themselves. Procedures employed to prepare a sample for viewing in the electron microscope may alter the structure of the virus. Disrupting the virion and separating its components for biochemical and biophysical analyses provides further opportunities for artifacts. However, these procedures also provide complementary information about the structure of the virion. Facts about the structure can be derived from the evidence at hand only, when a number of seemingly independent observations converge on and mutually support a conclusion. The structure proposed in the chapter is, therefore, intended to be a working model, based on the present state of knowledge. It is put forth at this time as much to provoke questions as to answer them.
77 citations
TL;DR: The results suggest that this entity has a predilection for the 40 to 59-year age group, a male: female ratio of 2:1, and was most frequently encountered on the tongue.
76 citations
TL;DR: The authors showed that double stranded RNA (thereplicative form) contains poly(A) at the 3′-end of the plus (genome-like) strand which is longer than poly (A) found in polio virion RNA.
Abstract: Poliovirus double stranded RNA (the “replicative form”) contains poly (A) at the 3′-end of the plus (genome-like) strand which is longer than poly (A) found in polio virion RNA. Digestion with 3′-exonuclease, hybridization to labelled poly (A) or poly (U) and affinity chromatography reveal that the minus strand contains 3′-terminal poly (U). These findings may imply that polio RNA replication proceeds through circular structures.
70 citations
TL;DR: Herpesviruses with oncogenic properties have also been isolated from monkeys7 and rabbits8, although their role in cancer has not been established.
Abstract: RECENT studies associate herpesviruses with neoplastic diseases of several animal species and man (see review by Klein1). Direct evidence links herpesviruses with the aetiology of Marek's disease of chickens2 and with the Lucke adenocarcinoma of the frog3–6 and less direct but persuasive data associate the Epstein-Barr herpesvirus with human Burkitt's lymphoma1. Herpesviruses with oncogenic properties have also been isolated from monkeys7 and rabbits8, although their role in cancer has not been established.
69 citations
TL;DR: Apparently, in vivo, the volume of the red cell in exercising healthy human subjects does not change measurably, in spite of significant changes in osmotic pressure of the surrounding medium, and it is not justified to correct postexercise hematocrit measurements for changes in plasma osmolarity.
Abstract: The volume of the red cell in vivo was measured during acute changes in plasma osmolarity evoked through short (6 to 8 min) maximal exercise in six male volunteer subjects. Simultaneous measurements of mean corpuscular red cell volume (MCV), hematocrit, blood hemoglobin, mean corpuscular hemoglobin concentration (MCHC), and plasma osmolarity showed that there was no change in the MCV or MCHC with a concomitant rise of nearly 6% in plasma osmolarity. Apparently, in vivo, the volume of the red cell in exercising healthy human subjects does not change measurably, in spite of significant changes in osmotic pressure of the surrounding medium. Consequently, it is not justified to correct postexercise hematocrit measurements for changes in plasma osmolarity.
TL;DR: Findings suggest that the apparent effectiveness of racemic epinephrine might be due to the nebulization of moisture rather than a direct effect of the drug.
Abstract: The effectiveness of racemic epinephrine in the treatment of croup was evaluated by a retrospective review, a prospective protocol, and a controlled study. Although the majority of children who were treated with racemic epinephrine and evaluated prospectively had significant immediate clinical improvement, the therapeutic regimen did not seem to affect the overall duration of hospitalization or the incidence of tracheotomy during the study period. Ten of the 20 children who participated in the double-blind controlled study had significant improvement; five received racemic epinephrine and five received the placebo. These findings suggest that the apparent effectiveness of racemic epinephrine might be due to the nebulization of moisture rather than a direct effect of the drug. The present study points out the critical need for controlled studies in the evaluation of therapeutic procedures in the treatment of croup.
TL;DR: A partially purified enzyme from Vinca rosea was shown to catalyze the transfer of the methyl group of S-adenosyl-l-methionine to loganic acid forming loganin, an intermediate in the biosynthesis of indole alkaloids of this plant.
TL;DR: Cell-free extracts of Vinca rosea seedlings exhibited enzyme activities for the following reactions: S-adenosyl-L-methionine decarboxylation, spermidine synthesis from decar boxylated SAM and putrescine, and 5′-methylthioadenosine hydrolysis to 5-S-methyl-5-thio-D-ribose and adenine.
TL;DR: In this paper, a new definition of atomic charges in molecules is presented which conserves charge and dipole moment, which allows for a systematic improvement of charges paralleling the improvement of the basis set in the LCAO approximation.
Abstract: A new definition of atomic charges in molecules is presented which conserves charge and dipole moment. It contains the Mulliken and Lowdin definitions as special cases of zero and first order truncations of commutator expansions. The definition allows for a systematic improvement of charges paralleling the improvement of the basis set in the LCAO approximation. We have tested the definition in thirteen selected diatomics and polyatomics in optimal minimal Slater basis set SCF calculations by means of 4G-level Gaussian expansions. The results suggest that the proposed definition is better than either Mulliken's or Lowdin's definition.
TL;DR: It is suggested that prostaglandins may play a universal role in the expulsion of the uterine content after it was found that term pregnant rabbits failed to deliver after an i.v. oxytocin challenge and the coturnix quail was inhibited by indomethacin.
TL;DR: Fatty acids appear to be unique among physiologically occurring effectors of fructose 1,6-diphosphatase in that they serve as potent activators and also protect the enzyme from ATP inactivation.
TL;DR: PGE levels in the plasma or serum of normal, pregnant and parturient women were determined by a specific radioimmunoassay while significantly higher values were observed during labor, reaching a mean maximum at cervix dilatation of 6–9 cm.
TL;DR: In this article, four groups of pigeons were trained to discriminate between red and green, and the groups differed with respect to the procedure used to introduce S−: Early-Progressive, Early-Constant, Late-progressive, and Late-Convariant.
TL;DR: Differential inhibition by intercalating dyes of catabolite-sensitive enzyme induction is reversed by cyclic AMP and could be due to in vivo differences in DNA conformation which increase the accessibility of the promoter region for dye binding and thus selectively inhibit transcription.
Abstract: Differential inhibition by intercalating dyes of catabolite-sensitive enzyme induction is reversed by cyclic AMP and could be due to in vivo differences in DNA conformation which increase the accessibility of the promoter region for dye binding and thus selectively inhibit transcription.
TL;DR: The pharmacologic use of vitamin E in doses 10 to 50 times the daily requirement was recommended in 1947 for the treatment of a variety of cardiovascular disorders, but no evidence of its effectiveness has been convincingly verified during the ensuing 25 years.
Abstract: Although vitamin E deficiency in ruminants results in conspicuous heart disease, a similar deficiency state in primates appears to spare the heart, even when other systems are affected. No heart disease in man has been related to a vitamin E deficiency. The pharmacologic use of vitamin E in doses 10 to 50 times the daily requirement was recommended in 1947 for the treatment of a variety of cardiovascular disorders, including intermittent claudication, angina pectoris, coronary occlusion, congestive heart failure, thrombophlebitis and thromboembolism, but no evidence of its effectiveness has been convincingly verified during the ensuing 25 years.
TL;DR: There was no apparent difference between CS and CR parasites with respect to 14C-amodiaquin binding, whereas erythrocytes infected with CR parasites have a deficiency of14C-chloroquine binding, probably accounts for its superiority in the treatment of the owl monkey and of humans infected withCR P. falciparum.
Abstract: 14 C-amodiaquin and 14 C-chloroquine were used to study drug binding by preparations of owl monkey erythrocytes infected either with a chloroquine-susceptible (CS) or with a chloroquine-resistant (CR) strain of P. falciparum . Both of these drugs are derivatives of 4-aminoquinoline, but they differ in their side chains, and there are differences in the way they are handled by preparations of erythrocytes infected with malaria parasites. Although the apparent association constant for the binding of either drug is approximately 10 7 mol −1 , two to three times more radioactivity was bound from 14 C-amodiaquin than from 14 C-chloroquine. Furthermore, there was no apparent difference between CS and CR parasites with respect to 14 C-amodiaquin binding, whereas erythrocytes infected with CR parasites have a deficiency of 14 C-chloroquine binding. This difference in the handling of amodiaquin probably accounts for its superiority in the treatment of the owl monkey and of humans infected with CR P. falciparum .
TL;DR: The results suggest that the incorporation of exogenous fatty acids, present in the medium perfusing the lung, into lung phospholipids may depend upon the fatty acid composition of the medium.
TL;DR: Electromyographic feedback was used to train a patient to inhibit spastic muscles voluntarily and improved muscle control could be seen even without the use of the EMG feedback device.
Abstract: Electromyographic (EMG) feedback was used to train a patient to inhibit spastic muscles voluntarily. The EMG activity was recorded with surface electrodes placed over the belly of the medial gastrocnemius muscle and displayed on a meter. The patient trained himself at home for thirty minutes daily for two months. Following training, improved muscle control could be seen even without the use of the EMG feedback device.
TL;DR: Treatment of Chinese hamster ovary cells (CHO-K1) with dibutyryl cyclic AMP and testosterone increases the production of RNA tumour virus-like particles thirty-fold or more, and induces a large increase in agglutinability by concanavalin A.
Abstract: Treatment of Chinese hamster ovary cells (CHO-K1) with dibutyryl cyclic AMP and testosterone increases the production of RNA tumour virus-like particles thirty-fold or more, and induces a large increase in agglutinability by concanavalin A.
TL;DR: It is shown that many mycoplasmas will grow in a chicken embryo tracheal organ culture system and that this system is well suited for quantitative studies and difficulties of methodology encountered and areas that deserve further investigation are pointed out.
Abstract: Several mycoplasmas cause respiratory illnesses in animals. The pathology and clinical symptomatology of many of these infections have been extensively studied in both natural and experimental infections. The results of laboratory in vitro studies with the various mycoplasmas associated with respiratory illnesses have suggested several factors that could be responsible for the pathogenesis of these infections under natural conditions. At present, however, very little is known about the in vivo pathophysiology of respiratory illnesses due to mycoplasmas. Since pulmonary infections are usually the result of downward spread of microbial agents, it would seem likely that the study of living respiratory epithelium during infection would offer valuable information relating to pathogenesis. Recently several including our~elves ,~-~l have shown that organ cultures of ciliated tracheal epithelium are useful in the study of mycoplasma pathogenicity factors. In particular, we have shown that many mycoplasmas will grow in a chicken embryo tracheal organ culture system and that this system is well suited for quantitative ~tudies.7-l~ It is the purpose of this presentation to: (1) review our published and unpublished studies utilizing the chicken embryo tracheal organ culture system; (2) present our studies with other organ cultures; (3) review the studies of others; and (4) point out difficulties of methodology encountered and areas that deserve further investigation.
TL;DR: In this article, the authors examined the longitudinal and latitudinal distribution of paleomagnetic poles during a polarity change and concluded that the geomagnetic field retains its dipolar character during polarity changes.