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61.
This study aimed to describe the change in the number of successful nests of the white-tailed eagle, Haliaeetus albicilla, for 25 years (1997–2021) along the Teshio River (100 km), Japan, which is a new habitat for this endangered species and identify factors driving the number of nests. The number of nests grew from two to nine. The logistic function fitted in well with the growth, and the capacity of the study area sustaining the successful nests was estimated at 6.5. The precipitation in January and April explained the deviation of the observed values from the model prediction. In particular, heavy rain in April was associated with low numbers. Forty-six nest remains were collected from 17 nest locations. Twelve genera of birds, six genera of mammals, and four genera of fishes were identified. Fish and bird items occupied 93.6% of prey individuals. The fish proportion was similar between high-performance years when the observed number of successful nests was higher than the model prediction and low-performance years with a lower number than the prediction (55.2% and 51.0%). However, it was higher in the nests with two fledglings (63.0%) than those with a single fledgling (41.5%). The nearest neighbor distance (NND) of the successful nests declined with the increase in the number of nests. Based on territory size (the mean NND = 7.8 km), the study area can hold 13 nests. The process and mechanism of the dynamics of the number of nests were discussed, focusing on territoriality and weather effects. 相似文献
62.
Sakamoto Norihiro; Takagi Toshihisa; Sakaki Yoshiyuki 《Bioinformatics (Oxford, England)》1993,9(4):427-434
We have developed ODS (Overlapping Oligonucleotide Databasefor Signal Sequence Search)the first relational databasethat integrates information on biological features into thesearch for signal sequences. In existing biological sequencedatabases, even relational ones, retrieving nucleotide sequencesbased on their biological features involves much labour andtime or even the development of a new program. GenBank sequencedata, including FEATURES records, are organized into three relationaltables in ODS. Nucleotide sequences are transformed into overlappingoligonucleotides in order to facilitate the signal sequencesearch rapidly without the need for specific alignment programs.This transformation leads to a one-to-one correspondence betweenthe nucleotide sequence and its biological feature. The signalsequence search by ODS is done in SQL queries and ODS obviatesthe need for molecular biologists to write computer programs.The application of ODS to searches of promoter regions revealedputative cis-acting elements and basic statistical analysesof occurrences of oligonucleotides showed interesting findingsconcerning the cg dinucleotide. 相似文献
63.
64.
M Shimizu E Ichikawa U Inoue T Nakamura T Nakajima H Nojima H Okayama K Oda 《Molecular and cellular biology》1995,15(5):2882-2892
65.
66.
Shinichi Watanabe Masayoshi Osumi Takamitsu Ohnishi Eiko Ichikawa Hisashi Takahashi 《Histochemistry and cell biology》1995,103(6):425-433
In order to investigate the re-epithelialization process during wound healing, the hair on the back of guinea pigs was shaved and then excisional wounds were made through the entire thickness of the skin. Histological changes were observed and changes in the expression of different cytokeratin polypeptides were examined using an immunohistochemical technique. Immunohisto chemical study revealed that the proliferating and migrating keratinocytes expressed the same cytokeratins as the basal cells of normal epidermis. In addition, the entire epidermis of fairly remote areas from the edges of the wound where no thickening was observed showed a temporarily abnormal staining pattern. The suprabasal cells in the regenerating epidermis temporarily expressed cytokeratins not only specific for suprabasal cells but also specific for basal cells. The cytokeratins expressed in normal basal keratinocytes were also present in the thickened granular layers. These data indicate that the expression of cytokeratins in the epidermal keratinocytes (even in fairly remote areas from the wound edges) changes during wound healing, that the origin of the migrating keratinocytes from the remaining epidermis seems to be the basal cells in the epidermis, and that the appearance of keratohyalin granules is not related to changes in cytokeratin expression. 相似文献
67.
68.
Monodehydroascorbate Reductase in Spinach Chloroplasts and Its Participation in Regeneration of Ascorbate for Scavenging Hydrogen Peroxide 总被引:15,自引:0,他引:15
The primary reaction product of chloroplast ascorbate peroxidaseactivity was shown to be monodehydroascorbate radical (MDA).MDA reductase (EC 1.6.5.4
[EC]
) was localized in spinach chloroplaststroma. The MDA reductase activity of spinach chloroplasts,using NAD(P)H as electron donor, could account for the regenerationof ascorbate from MDA produced by ascorbate peroxidase activity.In the absence of MDA reductase, MDA disproportionated to ascorbate(AsA) and dehydroascorbate (DHA). The DHA was reduced to AsAby DHA reductase (EC 1.8.5.1
[EC]
) in chloroplasts. Both NADH andNADPH served as the electron donor of partially purified MDAreductase from spinach leaves. (Received September 24, 1983; Accepted January 23, 1984) 相似文献
69.
Summary Pituitary glands were examined using reference staining (hematoxylin and eosin, periodic acid-Schiff and alcian blue) and the peroxidase-labeled antibody method, for 1) invading anterior cells in the posterior lobe, 2) intermediate colloid forming follicles, and 3) pars tuberalis cells.The results showed: 1) that the majority of cases possessed invading anterior cells of various amount. Most of these cells were positive for ACTH1–18, ACTH17–39 and -MSH. However, on a few occasions, scattered GH, PRL, FSH, FSH, LH and even TSH cells were also present. 2) Colloid forming follicular cells were mostly ACTH cells, but also contained occasional other hormone-secreting cells. Hormone negative cells were correlated with salivary type epithelium. Well established acinic type salivary glands and ciliated epithelium were negative for any hormones immunohistochemically. 3) Pars tuberalis cells were predominantly gonadotrophs but also included TSH and ACTH cells. Some cells appeared to contain both FSH and LH. When these cells underwent squamous metaplasia, they seemed to lose their hormone secreting activity.Part of this study was supported by a Grant-in-Aid for Cancer Research from the Ministry of Education, Science and Culture, Japan 相似文献
70.
An NADPH-hepatoredoxin reductase was purified from mitochondria of rabbit hepatocytes. The optical absorption spectrum showed a typical flavoprotein. The NADPH-hepatoredoxin reductase has an FAD as a coenzyme and the molecular weight of the NADPH-hepatoredoxin reductase was estimated to be 51000 by SDS-polyacrylamide gel electrophoresis. The NADPH-hepatoredoxin reductase was immunochemically similar to NADPH-adrenodoxin reductase of bovine and pig adrenocortical mitochondria, but not NADPH-cytochrome P-450 reductase of rabbit liver microsomes. The NADPH-cytochrome c reductase activity of the NADPH-hepatoredoxin reductase and hepatoredoxin complex, unlike NADPH-cytochrome P-450 reductase, was decreased by increasing ionic strength. 相似文献