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791.
792.
We studied the avifaunas of five cloud forest localities at 3000–3350 mas1 on the eastern slope of the Andes of Ecuador A method standardised for area, altitude and effort was the basis for obtaining data on species richness and abundances Richness and abundances (diversity) were unchanged along the limned latitudinal gradient (530 km) studied, whereas there was a considerable turnover in community structure between localities This result has important implications for ranking conservation priorities the total community richness and the dominance/evenness component of diversity does not provide a basis for making priorities along this limited latitudinal gradient Instead, species compositions and species referred to threatened categories (e g, endemics, restricted–range, IUCN threatened/near–threatened, CITES) will be the most meaningful data for making priorities for conservation We compared our results with similar results from the Andean western slope of Ecuador, obtained with the same method and standardised for time of the year The number of species was significantly higher on the eastern slope than on the western slope, a characteristic that can be explained from differences in extension of adjacent source areas and geohistory However, because the species compositions on the two slopes are rather different, it is not recommended to use the difference in richness to rank conservation priorities Abundances were quite similar on both sides of the Andes Contrary to the general belief, the montane avifaunas investigated have tropical and not temperate species richness which agrees with the tropical clutch sizes found among montane birds The avian richness found on the eastern slope of Ecuador near the Equator is definitely among the highest m the world for this altitude 相似文献
793.
Karina Hansen Kjaer Jesper Buchhave Poulsen Tõnu Reintamm Emilie Saby Pia Moeller Martensen Merike Kelve Just Justesen 《Journal of molecular evolution》2009,69(6):612-624
The 2′-5′-oligoadenylate synthetase (OAS) belongs to a nucleotidyl transferase family that includes poly(A) polymerases and
CCA-adding enzymes. In mammals and birds, the OAS functions in the interferon system but it is also present in an active form
in sponges, which are devoid of the interferon system. In view of these observations, we have pursued the idea that OAS genes
could be present in other metazoans and in unicellular organisms as well. We have identified a number of OAS1 genes in annelids,
mollusks, a cnidarian, chordates, and unicellular eukaryotes and also found a family of proteins in bacteria that contains
the five OAS-specific motifs. This indicates a specific relationship to OAS. The wide distribution of the OAS genes has made
it possible to suggest how the OAS1 gene could have evolved from a common ancestor to choanoflagellates and metazoans. Furthermore,
we suggest that the OASL may have evolved from an ancestor of cartilaginous fishes, and that the OAS2 and the OAS3 genes evolved
from a mammalian ancestor. OAS proteins function in the interferon system in mammals. This system is only found in jawed vertebrates.
We therefore suggest that the original function of OAS may differ from its function in the interferon system, and that this
original function of OAS is preserved even in OAS genes that code for proteins, which do not have 2′-5′-oligoadenylate synthetase
activity. 相似文献
794.
795.
H S Poulsen L Ozzello W J King G L Greene 《The journal of histochemistry and cytochemistry》1985,33(2):87-92
Two monoclonal antibodies against MCF-7 human estrogen receptors were used for immunoperoxidase staining of paraffin sections of human breast cancer tissue. The staining was predominantly located in the nucleus of epithelial cells. Variation in the staining intensity was observed among individual cells. A significant positive correlation between the number of positively stained cells and cytosol estrogen receptor content (fmol of bound estrogen/mg of protein) was observed. The potential and the limitations of the present techniques are discussed. 相似文献
796.
L M?rch-J?rgensen H S Poulsen L I Larsson 《Virchows Archiv. B, Cell pathology including molecular pathology》1979,30(3):281-287
The combined formaldehyde-fluorescamine technique demonstrates fluorescence by mammary carcinoma cells whereas cells of the normal gland or of benign tumours do not show fluorescence. We have studied the correlation between histological staging of the disease, concentrations of oestrogen-binding proteins and the occurrence of formaldehyde-fluorescamine (FF)-inducible fluorescence. Our results demonstrate that the FF-technique detects all types of mammary carcinoma cells irrespective of their concentration of oestrogen receptors. Hence, the FF-technique represents a valuable tool for detecting both hormone-responsive and hormone-unresponsive malignant cells of the mammary gland. 相似文献
797.
G K Mbassa J S Poulsen 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,100(2):423-431
1. Plasma urea, creatinine, bilirubin, glucose, cholesterol and total serum proteins were determined in Danish landrace goats from five herds in early and late gestation, during lactation and in dry goats. The purpose was to determine if there are sustained alterations in the levels of these parameters due to pregnancy and lactation and whether the changes are dependent on age, parity and environment. 2. Urea, creatinine and bilirubin were higher in young non-pregnant goats than in others. Urea decreased in goats at early and mid-lactation directly proportional to parity so that the higher the parity the more the decrease. 3. Creatinine was higher in young and adult non-pregnant goats than in others. There was an increase in late lactation that was greater in goats of higher parity than in others. 4. Bilirubin was higher in the mid-lactation stage, much more in goats of higher parity than in others. 5. Glucose concentration was lower in pregnant than in lactating goats and increased during lactation. The decrease during pregnancy was greater in higher parity goats than in others. 6. Plasma cholesterol and total serum proteins increased during lactation directly proportional to parity. 7. There were significant differences in biochemical parameters between goats from different herds (within similar physiological states). 8. Sustained alterations of these biochemical parameters occur during pregnancy and lactation in goats; the magnitude of changes depends on age and parity, and varies between herds. 相似文献
798.
A H Nielsen P Gotfredsen P B Nielsen P Hyttel K Poulsen 《Comparative biochemistry and physiology. A, Comparative physiology》1991,100(1):127-131
1. Species specific problems complicating the measurement of prorenin and renin concentrations were studied in bovine, hog and horse plasma. 2. In contrast to horse renin, bovine and hog renin reacted with rat angiotensinogen, allowing measurement of the plasma renin concentration in cattle and hog with rat angiotensinogen as exogenous substrate. 3. Trypsin treatment of plasma in order to activate prorenin generated an interfering angiotensin I immunoreactive material in all three species, most extensively in horse plasma. 4. This material could be removed in bovine and hog plasma by a cation-exchange resin, allowing an assay of the plasma prorenin concentration to be constructed in these species. 5. Another strategy has to be followed in order to measure prorenin and renin concentrations in horse plasma. 相似文献
799.
Brodie Caroline BSc MB Kapur Ritu MD Murray Mary MAMLS Magee Derek FAMLS Turner Lesley FAMLS Gibbons David MB FCAP 《Cytopathology》2003,14(S1):4-4
Both the original Bethesda system and the current UK classifications of cervical cytology have proved robust but each has a major weakness in the area of abnormalities of uncertain significance. Cytologists recognize that sometimes it is simply impossible to differentiate between reactive and dyskaryotic material. For this reason, the Australian version of the Bethesda system introduced a new category of 'high grade inconclusive' with a recommendation for referral to colposcopy. Approximately 60% of such cases are found to have high grade lesions at colposcopy (Schoolland M, Sterrett G, Knowles S et al .). The present UK system even with the proposed changes requires of the pathologist, a decision as to whether such cases are probably high grade (=a report of moderate dyskaryosis) or not (= a report of borderline). This continues to ignore the fact that sometimes you just cannot tell, even on review. We have taken a consecutive series of 50 referral smears, reported as moderate dyskaryosis, where the histological outcome (by loop cone) is known. These cases were rescreened and then reviewed blind by a pathologist with extensive experience of the Australian NH & MRC modified Bethesda system. On review, the material was reclassified along NH & MRC lines. The results were compared with the biopsy findings in order to determine whether the category of 'inconclusive' might be of value in the context of the NHSCSP. 相似文献
800.
The availability of pure submaximillary renin, its antibody and pure specific immunoreactive Fab fragments of the antirenin molecule were used in an attempt to detect in which form renin is stored in the submaxillary gland. The proteolytic activity of serine-, metallo- and sulfhydryl enzymes during homogenisation was inhibited, but no inactive or high molecular weight form could be detected enzymatically or antigenically after gelfiltration. Nor were they demonstrable in crossed immuno-electrophoresis by using antibodies elicited against pure renin. Furthermore, pepstatin which additionally inhibits acid proteases, including a possible autoactivation of renin, and renin specific Fab fragments, were added, the latter in order to steric hinder proteolytic attack on a possible renin precursor. The renin-Fab complex was purified by precipitation with anti-Fab antibodies. No high molecular weight renin was demonstrable in SDS polyacrylamide gel electrophoresis. The only form of renin demonstrable in the submaxillary gland of mice was the fully active 40,000 dalton form. Its specific enzymatic activity was identical to that of pure submaxillary renin, being 0.4 . 10(-3) Goldblatt unit . ng-1. 相似文献