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21.
The application of beta-radiation in coronary arteries is a promising new technique for the treatment of in-stent restenosis. This is the first case in which the 5 F. delivery catheter of the Beta-Cath trade mark system was advanced through the struts of a stent, previously deployed in an adjacent branch, so as to deliver radiation to the target vessel.  相似文献   
22.
The Tamezzakht succession (Maastrichtian–middle Burdigalian), situated at the fringe between the Internal and the External zones, displays contrasting lithologies with abrupt facies changes, discontinuities, and/or coarse-grained calciturbidite in between. These criteria allow the definition of seven main lithostratigraphic formations.Depositional environments (oxygenation levels, trophic conditions, omission histories, among others) and/or transgressive/regressive trends are inferred from integrated sedimentologic data including facies change, cyclicity pattern and the textural composition of the turbidite facies tracts. Special emphasis is given to the ichnological features.Taking into account the extended time-range, the position between the internal zones and the external ones, as well as the clear differentiation into several contrasting sedimentary formations, the Tamezzakht succession is expected to provide useful stratigraphic data for the regional correlations.  相似文献   
23.

Background  

The accurate identification of Lactobacillus and other co-isolated bacteria during microbial ecological studies of ecosystems such as the human or animal intestinal tracts and food products is a hard task by phenotypic methods requiring additional tests such as protein and/or lipids profiling.  相似文献   
24.
Abstract. Since the construction in 1979 of a dam in the Logone floodplain in the Sahelo‐Sudanian zone of Cameroon, annual inundations have decreased, reducing perennial vegetation as important grazing source for nomadic herds and wildlife during the dry season. Presently, possibilities exist to release excess water for floodplain rehabilitation. In 1994 a pilot release was executed, reflooding 200 km2, to verify predicted advantages. Vegetation has been studied from 1984 onwards along a transect covering flooded, recently reflooded and desiccated parts of the floodplain. Since 1993, the floristic composition has also been monitored in a grid in the centre of the impact zone. Cover of perennial grasses, most notably Echinochloa pyr amidalis and Oryza longistaminata increased from 41 to 61% in the reflooded zone. Vetiveria nigritana, a tussock grass that used to be dominant, disappeared slowly after the dam construction and has not shown a comeback. The cover of annual species, most notably Sorghum arundinaceum, a dominant annual grass only since the mid‐1980s, decreased in the reflooded zone from 58% to 34%. If the present conversion rate of annual into perennial grassland is extrapolated, recovery towards a 100% perennial state may be reached after the 2003 flooding season. Apart from favourable climatic conditions, recovery might be dependent on the restoration of soil fertility, limiting an approach focusing on flooding depth only.  相似文献   
25.
The aim of this study is determining the different patterns of egg nests and the morphological differences between the specimens of Cicadatra persica Kirkalidy, 1909 (Hemiptera: Cicadidae) distributed in fruit orchards in Erneh located on AL-Sheikh mountain south west of Syria. The appearance of 80 egg nests was studied, and the results showed that there were two basic patterns of egg nests laid by Cicadatra persica, 90% of the egg nests were of the first pattern (consists of several adjacent slits), while 10% of them were of the second pattern (consists of several divergent slits). A random sample consisting of 300 specimens (150 males and 150 females) were also studied concentrating on the differences in the color of the supra-antennal plate and in the number of spurs on the tibia of the hind legs. The results showed that there were two basic patterns of individuals based on the differences in the color of supra-antennal plate. The first pattern (individuals with yellow supra-antennal plates), constituted more than 90%, and the second one (individuals with black supra-antennal plates) constituted less than 10%. The results also showed that there were 27 different patterns based on the number of spurs on the tibia of the hind legs. One of them was a common pattern (2, 3) whose individuals have 2 spurs on the upper side of the tibia of the hind legs and 3 spurs on the lateral side of the tibia of the hind legs. The total percent of this common pattern was 76%. The other 26 patterns were different from each other, and the total percent of all these different patterns was 24%.  相似文献   
26.
Reliable immunohistochemical detection of collagen in formalin fixed, paraffin embedded tissues requires protease digestion. While these pan-proteases (pepsin, trypsin, protease K, etc.) enhance collagen detection, they also digest many other tissue proteins and produce poor cellular morphology and unrecognizable cellular structures. Balancing the conditions (protease type, concentration, incubation time and temperature) to digest some, but not all, proteins in a tissue section while optimizing collagen detection requires one to compromise improved collagen immunolabeling with adequate cellular morphology. Furthermore, optimal conditions for digesting tissue proteins to enhance collagen detection vary among tissue types and their fixation. Although brain is not typically subject to these deleterious consequences, structures such as epithelium, spermatids, stroma etc. and other tissues with complicated histology are profoundly affected. To resolve this technical dilemma, we discovered a novel use for collagenase to enhance collagen immunodetection without affecting the noncollagen proteins, thereby preserving tissue morphology. Collagenase, which is typically used in vitro for disassociation of cells, has never been used reliably on formalin fixed, paraffin embedded tissue sections. This new use of collagenase for immunohistochemistry promotes increased collagen immunolabeling, is easy to use, is versatile, and allows preservation of tissue structure that provides maximal and accurate histological information.  相似文献   
27.
Sediment characteristics and vegetation composition were measured in a restored and natural saltmarsh and mudflat at Wallasea Island managed realignment scheme (Essex, UK) from January to December 2007. The similar sediment characteristics in the restored and natural mudflat indicated that the sediment in the restored mudflat was approaching natural conditions. However, the sediment characteristics in the restored saltmarsh were not becoming similar to those in the natural saltmarsh. The sediment moisture content, organic matter content and porosity were lower while the sediment bulk density, salinity and pH were higher in the restored compared to the natural saltmarsh. The dissimilarities were mainly due to differences in the vegetation abundance and organic matter content. Although, 18 months after restoration the restored saltmarsh was only sparsely vegetated and there was no net change in the sediment characteristics, the occurrence of Salicornia europaea L. demonstrated that pioneer saltmarsh vegetation establishment preceded the development of sediment characteristics.  相似文献   
28.
Glyceroneogenesis, a metabolic pathway that participates during lipolysis in the recycling of free fatty acids to triglycerides into adipocytes, contributes to the lipid-buffering function of adipose tissue. We investigated whether glyceroneogenesis could be affected by human immunodeficiency virus (HIV) protease inhibitors (PIs) responsible or not for dyslipidemia in HIV-infected patients. We treated explants obtained from subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) depots from lean individuals. We observed that the dyslipidemic PIs nelfinavir, lopinavir and ritonavir, but not the lipid-neutral PI atazanavir, increased lipolysis and decreased glyceroneogenesis, leading to an increased release of fatty acids from SAT but not from VAT. At the same time, dyslipidemic PIs decreased the amount of perilipin and increased interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) secretion in SAT but not in VAT. Parthenolide, an inhibitor of the NFκB pathway, counteracted PI-induced increased inflammation and decreased glyceroneogenesis. IL-6 (100 ng) inhibited the activity of phosphoenolpyruvate carboxykinase, the key enzyme of glyceroneogenesis, in SAT but not in VAT. Our data show that dyslipidemic but not lipid-neutral PIs decreased glyceroneogenesis as a consequence of PI-induced increased inflammation in SAT that could have an affect on adipocytes and/or macrophages. These results add a new link between fat inflammation and increased fatty acids release and suggest a greater sensitivity of SAT than VAT to PI-induced inflammation.  相似文献   
29.
The species are generally amphistomatic except Pandiaka heudelotii that is hypostomatic. Anomocytic and paracytic stomatal types were mostly found but cyclocytic and diacytic types may accompany, especially in Cyathula spp. The anticlinal wall pattern varies from undulate to curved and curved‐straight in the family. Other useful epidermal features are peltate scales, trichomes of different types such as candelabra type, unicellular and multicellular conical types, long acicular glandular forms that may be tuberculate or non‐tuberculate and the filiform type; all can be employed at species level for delimitation purpose. Sub‐familial grouping of the genera is supported while monophyly and polyphyly suggested in Gomphrenoideae and Amarantheae respectively can be inferred from the extent of character variations in the species. An indented dichotomous key is presented for species delimitation. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
30.
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