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101.
An ascomycete with an anamorphic state was described from Eocene age material from Henry County, Tennessee, U.S.A., as Pelicothallus villosus Dilcher. This organism is reinterpreted as an alga. 相似文献
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103.
The effectiveness of budesonide, a new non-halogenated glucocorticoid administered by nasal inhaler, was evaluated in a double blind comparison with placebo in patients presenting with hay fever. Patients were supplied with antihistamine tablets and eye drops for use when they considered that their symptoms were inadequately controlled by their inhaler. Patients recorded the severity of their symptoms in a daily diary card and visited their general practitioner for assessment weekly for four weeks. All nasal symptoms of hay fever were appreciably reduced in the group taking budesonide and, although their eye symptoms were more severe than in the group taking placebo, they did not use appreciably more eye drops than the latter. The placebo group used appreciably more antihistamine tablets than those in the budesonide group. No patients were withdrawn from the budesonide group because of treatment failure or unacceptable side effects. The results suggest that budesonide is an acceptable and effective treatment for the nasal symptoms of hay fever. 相似文献
104.
The true incidence of the lupus syndrome induced by hydralazine was determined in a longitudinal study of 281 patients consecutively starting hydralazine for hypertension over a 51 month period. Data on the duration of treatment and the maximum dose achieved were examined using life table analysis. After three years'' treatment with hydralazine the incidence of the lupus syndrome was 6.7% (95% confidence limits 3.2-10.2%). The incidence was dose dependent, with no cases recorded in patients taking 50 mg daily and incidences of 5.4% with 100 mg daily and of 10.4% with 200 mg daily. The incidence was higher in women (11.6%) than in men (2.8%). In women taking 200 mg daily the three year incidence was 19.4%. Hydralazine is an effective antihypertensive drug that has come to be used in restricted dosage (not more than 200 mg daily) because of its risk of inducing the lupus syndrome. This study shows that the true incidence of the syndrome is still unacceptably high even when the drug is prescribed according to current recommendations. 相似文献
105.
Synopsis Results of experimental transfer of rainbow smelt into lakes reclaimed by rotenone around 1960 in Maine were originally interpreted to cast doubt on the previously widely accepted hypothesis that there were two hereditarily different forms of rainbow smelt, one large and one small. Study of more recent data from some of the transplanted populations and reanalysis of the original data suggests different conclusions. The initial effect of introductions into a reclaimed lake may be accelerated and/or more prolonged growth which exceeds even interlake differences. This initial phase, however, is followed by a second phase, when the population reaches equilibrium and these effects subside. Data from phase two of the Little Concord-Shagg and Cold Stream-Coleback Lake transfers showed that the growth characteristics of the transplanted populations returned to those of the parental populations. Large differences in growth patterns were thus found only in the initial phase of the introduction. Meristic characters were little affected by transplanting.Analysis of large specimens derived from a postulated second unofficial introduction into Coleback Lake showed that they also differed significantly, having both higher gill raker and vertebral counts than the smaller smelt. This was of interest as smelt vertebral and gill raker counts usually are inversely related; hence we do not equate these for the moment with the large form of smelt known elsewhere.It is concluded that the initial interpretation of transfer experiments be delayed until conditions approaching equilibrium can be expected to exist. Further, our analysis of more recent lake transfer data has shown nothing to refute the hypothesis that there are at least two hereditarily different forms of smelt. 相似文献
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108.
To test for the presence of polarizing mesoderm in an amphibian, Xenopus laevis hindlimb bud tips were rotated 180° on the proximodistal axis and returned to the stump. Supernumerary outgrowths were induced in the preaxial stump and preaxial tip tissues, and the most postaxial digit always formed next to the grafted postaxial tissue. The occurrence of polarized supernumerary outgrowths indicated that the posterior limb border contained a polarizing zone. When the limb tip was cut at varying known lengths from the body wall, rotated, and grafted to the limb stump, the incidence of twinning along the proximodistal axis permitted insight into the distribution of the polarizing zone along the posterior border. The location of polarizing tissues was found to be similar to that in the chick wing bud at comparable stages. To confirm the posterior border stump influence on the rotated preaxial limb tip tissues, 180° tip rotations were made at the proximodistal level with the highest incidence of twinning. In these cases, the adjacent stump posterior border tissues (polarizing zone) were removed, leaving a substantial amount of the deeper postaxial stump tissue, however. The frequency of twinning from tip tissues was greatly reduced in these larvae compared to those with rotated limb tips on intact stumps. Cytological examination of supernumerary outgrowths resulting from grafts of two-nucleolate tips onto one-nucleolate stumps confirmed the preaxial source of the supernumerary outgrowths. 相似文献
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110.
High-pressure liquid chromatography (HPLC) was used to assay for catecholamines released into the heart of the goldfish (Carassius auratus L.) upon stimulation of vagal nerve fibers. Stimulation induced the release of norepinephrine, epinephrine and dopamine into the lumen of the perfused, isolated heart. The results suggest that heart activity in teleosts is directly modulated by functional adrenergic, cardioacceleratory nerve fibers. 相似文献