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991.
ABSTRACT

Skin collagen of six discarded fish species was analyzed and compared. Acid soluble collagen (ASC) was extracted; a characteristic sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profile for type I collagen was obtained, except for Chimaera mostrosa. Contents of collagen calculated from HPro (31.85% average) were higher than those determined from ASC extracts (17.75% average), with Galeus spp. being the species with the higher percentage. Amino acid analysis revealed the typical composition of collagen, with very few differences among species. Specific profiles were obtained after protease digestion. Denaturation temperature of ASC correlated well with imino and hydroxyproline contents.

Results demonstrate the feasibility of using the obtained collagens in different industrial applications.  相似文献   
992.
Two miniature Shetland ponies showing clinical signs of Digitalis purpurea (foxglove) poisoning were examined. One animal died shortly afterwards, but the second was treated successfully with the anti-arrhythmic agent, phenytoin, and was discharged after 16 days.  相似文献   
993.
994.
Unilateral ablation of the auditory cortex in the cat results in a profound deficit in attending to stimuli on the side contralateral to the lesion. The deficit is also manifested in an abnormal perception of left-right pulse pairs when the pulse which leads by a few milliseconds is contralateral to the damaged hemisphere.  相似文献   
995.
Using some of the chromosome substitution lines developed from thecrosses of the donor Cheyenne to Chinese Spring we showed that theaccumulation of water soluble carbohydrates during different stages ofhardening was time dependent. Moreover there was a significantcorrelation between the rate of carbohydrate accumulation and the frosttolerance. The expression and regulation of a wheat gene homologous tothe barley cold regulated cor14b gene was compared in frost sensitiveand frost tolerant wheat genotypes at different temperatures. Studies madewith chromosome substitution lines showed that the threshold inductiontemperature polymorphism of the cor14b wheat homologous genewas controlled by loci located on chromosome 5A of wheat, while cor14b gene was mapped, in Triticum monococcum, onto the longarm of chromosome 2Am. Our study on the effect of cold hardeningon glutathione (GSH) metabolism showed that chromosome 5A of wheathas an influence on the GSH accumulation and on the ratio of reduced andoxidised glutathione as part of a complex regulatory function during coldhardening. In addition, the level of increase in GSH content duringhardening may indicate the degree of the frost tolerance of wheat.  相似文献   
996.
Two hundred and twelve dog cadavers belonging to different breeds were examined, to investigate the formation of the femoral, obturator and the sciatic nerve. Besides the commonly described formation patterns of the mentioned nerves, some variations were also found. These variations were not gender-related, but on the other hand we discovered a certain correlation between the variations appearing in the formation of the femoral, obturator and the sciatic nerve. In 74.05% of cases, the femoral nerve was formed from ventral branches of the 4th, 5th and 6th lumbar nerve, and 16.98% of the dogs had the nerve formed from ventral branches of the 3rd, 4th and 5th lumbar nerve. Many dogs (i.e. 2.30%) had the femoral nerve formed from the ventral branches of the 5th, 6th and 7th, the 3rd, 4th, 5th and 6th or the 4th, 5th, 6th and 7th lumbar nerve, respectively. In 1.88% of dogs in particular, the femoral nerve was formed from ventral rami of the 4th and 5th lumbar nerve. In 66.98% of the examined dogs, the obturator nerve was formed from the ventral branches of the 4th, 5th and 6th lumbar nerve, followed by 16.59% of the dogs with the obturator nerve formed from the ventral rami of the 4th and 5th lumbar nerve and 9.43% of dogs in which the nerve was formed from the ventral branches of the 5th and 6th lumbar nerve. In 4.71% of dogs, the obturator nerve was formed from the ventral rami of the 4th, 5th, 6th and 7th lumbar nerve, while only 2.30% of the examined dogs had the same nerve formed from the ventral branches of the 5th, 6th and 7th lumbar nerve. The sciatic nerve was formed from ventral branches of the 6th and 7th lumbar nerve and the 1st sacral nerve in 86.79% of the dogs. In 5.18% of cases, the same nerve was formed from a junction of the ventral branches of the 7th lumbar and the 1st and 2nd sacral nerve, and, in the same percentage of cases, it was formed from a junction of ventral branches of the 6th and 7th lumbar nerve and the 1st and 2nd sacral nerve. In 2.83% of the dogs, it was formed from a junction of the ventral branches of the 6th and 7th lumbar and the 1st sacral nerve. The correlation of variations established in the formation of the femoral, obturator and the sciatic nerve was not statistically significant.  相似文献   
997.
An expert on local flora usually is the best option for plant species selection in most ecological restoration projects; although species selection often needs to be dealt with swiftly as well as on a limited budget, and obtaining the opinion of a local expert may not always be an economically viable alternative. In such cases, species distribution models (SDM) may offer a faster and more cost effective alternative. We asked six experts to rank native tree species according to their suitability at 24 forest sites. The predictive performance of the suitability rankings was evaluated by assessing their ability to discriminate present from absent species in the observed tree assemblages at each evaluation site. We used the area under the receiver operating characteristic curve to calculate the probability that the estimated suitability for a species present at a particular evaluation site is greater than the estimate for an absent species (both picked at random). Suitability rankings were also obtained from the predictions of SDM and the same procedure was used to estimate the predictive performance of the set of models at each site. The experts offered concordant suitability rankings at almost every evaluation site. There were no significant differences in the predictive performance of the SDM and four of the experts, although the SDM performed slightly better than the other two experts. Our results point to the suitability of the proposed species distribution modeling approach to obtain fast and cost effective recommendations for species selection in forest restoration projects.  相似文献   
998.
Leaves of red oak trees that had been defoliated by gypsy moth larvae during the previous year and again during the period of the study had higher values of tanning coefficients, total phenolics, hydrolyzable and condensed tannins, dry matter contents, and toughness than did leaves of undamaged trees. These changes may influence larval growth and alter the course of further outbreaks.  相似文献   
999.
1000.
Han KH  Shin DI  Keathley DE 《Tree physiology》1997,17(10):671-675
We studied the in vitro responses of cambial tissue and dormant vegetative buds obtained from top and epicormic branches of three mature black locust (Robinia pseudoacacia L.) trees. Cambial tissues isolated from epicormic branches produced more callus than cambial tissues isolated from top branches, whereas in vitro shoot cultures derived from buds excised from top branches grew faster than those derived from buds excised from epicormic branches. There were no significant differences between the two branch sources in in vitro bud break or shoot multiplication from bud explants or cambial-derived callus tissue, respectively. Furthermore, the top branches, generally considered to be the most mature in a tree, were not recalcitrant in terms of morphogenic capacity compared to epicormic branches.  相似文献   
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