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961.
The authors describe treatment possibility for AAA with renal arteries arising from aneurysmal sac in high operating risk patients. They combined endovascular stent-grafting for aneurysmal sac exclusion and classical vascular surgical iliacrenal bypass for revascularisation of excluded renal arteries.  相似文献   
962.
The function of an arteriovenous (av) fistula for haemodialysis may be complicated by manifestation of peripheral venous hypertension, which results from the arterial blood flow through the venous system into the periphery of the upper extremity. Its development is most typically caused by a proximal forearm av-fistula, as, in addition to the desirable arterialisation of the subcutaneous venous system of the arm, arterialisation of the venous system of the forearm and the hand may occur and possibly promote the development of venous hypertension, which may in the extreme result in gangrene of the fingers. Awareness of these problems as well as of the necessity of their surgical solution is essential for doctors dealing with haemodialysis.  相似文献   
963.
Cholera, an enteric disease that can reach pandemic proportions, remains a world-wide problem that is positioned to increase in incidence as changes in global climate or armed conflict spawn the conditions that enhance transmission to humans and, thus, precipitate epidemic cholera. An effective subunit cholera vaccine that can provide protective immunity with one parenteral immunization would be a major advantage over the existing oral vaccines that can require two doses for optimal protection. The existing vaccines are clearly effective in some settings, but are less so in others, especially with respect to specific groups such as young (2-5 years) children. In our efforts to develop a cholera subunit vaccine, we focused on two Vibrio cholerae antigens, LPS (lipopolysaccharide) and TCP (toxin co-regulated pilus), that are known to induce protective antibodies in animal models and, in the case of anti-LPS antibodies, to be associated with clinical protection of V. cholerae exposed or vaccinated individuals. This review discusses the current cholera vaccines and compares the advantages of a cholera subunit vaccine to that of the whole cell vaccines. We discuss the possible subunit antigens and prospective targeted use of a subunit cholera vaccine.  相似文献   
964.
In this study, we investigated the response of inland breeding cormorants Phalacrocorax carbo to a complex spatial configuration of feeding habitats in relation to social and individual feeding strategies. The numbers of feeding trips outside the colony site (Lake Grand-Lieu, western France), where only solitary fishing is used by cormorants, and the number of birds fishing on the lake where social fishing predominates were investigated during the breeding season and compared with the fledging period. From the investigation of feeding trip traffic, we identified three major habitats used by cormorants in the vicinity of the colony site (< 25 km around the colony site) that accounted for 94.1 of the IN flights and 92.0% of the OUT flights (n = 1745 arrivals and 2404 departures respectively), and notably one area that accounted for 58% of total flights although it is the furthest away. No fundamental change in the relative significance of these feeding grounds for solitary fishing cormorants was found throughout the breeding season, even in a between-years comparison (1996-2001), in contrast to what has often been found elsewhere. Although the peak of foraging activity in the surrounding habitats and also within the lake waters largely coincided with the time when the majority of young had fledged, the index of cormorant numbers (ratio between bird numbers at a given time and that for a baseline date) on the lake remained at a high level until late August compared to movements outside the lake, as a result of regular social fishing (84.9 +/- 4.0% of fishing numbers). From these findings, we discuss factors governing the selection of feeding grounds throughout the breeding season in relation to energy considerations, feeding strategies and food resources.  相似文献   
965.
Plants are necessarily complex systems that require monitoring of multiple environmental signals and, in response to those signals, coordination of differentiation and development of an extensive array of cell types at multiple locations. This coordination must rely on integration of long-distance signals that provide a means of communication among different plant parts. We propose that the relatively well-characterized classical phytohormones must act with several other long-distance signals to achieve this level of organization with dynamic yet measured responses. This is supported by observations that classical phytohormones: (i) operate in complex yet experimentally unresolved networks involving cross-talk and feedback, (ii) are generally multifunctional and nonspecific and hence must rely on other long-distance cues or pre-set conditions to achieve specificity and (iii) are likely to mask roles of other long-distance signals in several experimental contexts. We present evidence for involvement of novel long-distance signals in three developmental processes—branching, flowering and nodulation, and discuss the possible identities of novel signalling molecules.  相似文献   
966.
Fluorescent in situ hybridization followed by tyramide signal amplification was used to map the site of the c-SRC1 gene on XENOPUS LAEVIS chromosomes. Positive results were obtained with a cDNA probe of about 1 kb. The c-SRC1 gene is located in the subcentromeric region in the long arm of one of the acrocentric chromosomes of the G category (classified according to Graf and Kobel, 1991). The c-SRC1 gene and the XENOPUS major histocompatibility complex (MHC) 1b locus, which consists of 20 tandemly arranged gene copies, are situated on different chromosomes of the G category.  相似文献   
967.
The effects of sheep grazing on plant community structure and diversity were studied in saltmarshes of the Mont-Saint-Michel bay. This study took place at two scales: (1) at the scale of the entire bay to explore the changes in plant community over a ten year period; and (2) locally with the use of experimental exclosure set up to mimic the abandonment of grazing. Moderate grazing generally enhanced plant richness and diversity, while the absence of grazing and overgrazing lead to a decrease in diversity and richness. The development of management strategies is becoming critical to preserve the diversity of saltmarshes functions.  相似文献   
968.
Deviant genetic codes reported in ciliates share the same feature: one (UGA) or two (UAR) of the three canonical stop codons are translated into one particular amino acid. In many genera, such as Oxytricha, Paramecium, and Tetrahymena, UAR codons are translated into glutamine. UGA is translated into cysteine in Euplotes or into tryptophan in Colpoda inflata and Blepharisma americanum. Here, we show that three peritrich species (Vorticella microstoma, Opisthonecta henneguyi, and Opisthonecta matiensis) translate UAA into glutamate and that at least UAA in O. matiensis is decoded through a mutant suppressor-like tRNA. This kind of genetic code has never been reported for any living organism. Phylogenetic analysis with alpha-tubulin sequences corroborates that peritrichs, peniculines (Paramecium), and hymenostomates (Tetrahymena) form a monophyletic group (class Oligohymenophorea). The differential translation (glu/gln) of UAR codons, the monophyly of the Oligohymenophorea, and the common evolutionary origin of glutamate and glutamine suggest that deviant genetic codes of present-day oligohymenophoreans could have the same origin.  相似文献   
969.
The authors describe surgical treatment for high risk patients with abdominal aortic aneurysms of complicated morphology for standard endovascular repair. This was achieved by combining endovascular stent-grafting for aneurysmal sac exclusion with conventional vascular surgical procedures.  相似文献   
970.
The authors compare the functional outcome of 26 patients successfully treated by percutaneous osteosynthesis and 24 patients successfully treated by a short-arm thumb cast for the acute scaphoid fracture after a follow-up of at least 12 months. The patients treated by percutaneous osteosynthesis showed a significantly better range of wrist motion at the time of re-examination. Differences in persistent complaints and in grip strength compared to the uninjured wrist between both groups were statistically insignificant yet slightly in favour of the surgically treated patients. The higher suitability of percutaneous osteosynthesis is further supported by the significantly lower failure rate compared to conservative treatment. Based on these results, percutaneous osteosynthesis seemed to be the more favourable method of treatment of minimally and non-displaced scaphoid fractures than conservative treatment.  相似文献   
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