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Although anatomical properties and vessel variations of the celiac trunk are well explored in the literature, there is not so much information on the arterial diameters, and this data is important for surgical procedures and angiographic examinations. The aim of this study was to investigate properties of the celiac trunk in humans by using anatomical dissection. Ninety cadavers were dissected for the celiac trunk identification and arterial diameter measurements. The results of anatomical examination showed that in 72% of all cases the celiac trunk divides into the splenic artery and the common hepatic artery, while the left gastric artery arises as a first branch and had origin between aorta, all over the celiac trunk up to a bifurcation. From the 90 cadavers, 4 presented anatomical variations. Where normal anatomy was present, the mean length of the celiac trunk was 1.9 +/- 0.08 cm and its mean arterial diameter was 0.78 +/- 0.08 cm. The splenic artery had the largest diameter (0.61 +/- 0.05 cm) and the left gastric artery had the smallest diameter (0.38 +/- 0.03 cm). Our data represent original results about anatomical variations and arterial diameter of the celiac trunk and its main branches provided by anatomical dissection.  相似文献   
83.
The diet of juvenile and adult twaite shad was studied at a number of freshwater and estuarine sites in the rivers Severn and Wye and in the coastal waters of Cardigan Bay (West Wales). In the Severn estuary and in the freshwater reaches of the Severn and Wye, adult twaite shad consumed little during their pre-spawning migration. In the Severn Estuary post-spawning adults were present during the summer months where they fed actively on mysids, gammarids and shrimps. Mysids dominated the diet of the adults caught in coastal waters during the autumn. The diet of one year old twaite shad was studied in the Severn Estuary. In May the one year olds from the lower estuary consumed mainly gammarids. During the summer months, this age-class moved into the inner estuary where they fed predominantly on mysids.The larvae and juveniles (age 0+) fed mainly on chironomid larvae and pupae and Simuliidae larvae, while in fresh water. In the estuary copepods, cladocerans and mysids dominated the diet of the juveniles. There was some suggestion of an increase in prey size during their period of residency in the estuary. The contrasting distribution of the juveniles in two river systems is discussed in relation to the effects of channelization.  相似文献   
84.
The marine photosynthetic dinoflagellates Dinophysis Ehrenb. species are obligate mixotrophs that require both light and the ciliate prey Myrionecta rubra (= Mesodinium rubrum) for long‐term survival. Despite rapid progress on the study of Dinophysis using laboratory cultures, however, whether it has its own permanent plastids or kleptoplastids (i.e., stolen plastids from its ciliate prey) is not fully resolved. Here, we addressed this issue using established cultures of D. caudata Saville‐Kent strain DC‐LOHABE01 and cross‐feeding/starvation experiments encompassing the prey Mrubra strain MR‐MAL01 cultures grown on two different cryptophytes (strains CR‐MAL01 and CR‐MAL11). To follow the fate of prey plastids, psbA gene as a tracer was amplified from individually isolated D. caudata cells, and the PCR products were digested with a restriction enzyme, SfaNI. The RFLP pattern of the PCR products digested by SfaNI revealed that Dcaudata continued to keep CR‐MAL01–type plastids, while it lost CR‐MAL11–type plastids with increasing starvation time. Our results suggest that Dinophysis treats in different ways plastids taken up from different cryptophytes via its ciliate prey Mrubra. Alternatively, Dcaudata may already have its own CR‐MAL01–type permanent plastid, with two types of plastids (CR‐MAL01 and CR‐MAL11) obtained from Mrubra being lost within 1 month. This result highlights the need to identify more accurately the origin of plastids in newly isolated photosynthetic Dinophysis species to resolve the issue of plastid permanence.  相似文献   
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The 1991-1995 War for independence of Croatia was a cruel armed conflict, provoked by the conquering aspirations of the "Yugoslav Federal Army" under Serbian command and Serbian terrorists. It took place on the territory of the Republic of Croatia and gave rise to a mass destruction of civilian and sacral buildings and civilian massacres. Here we present three representative cases as an example of the massacre over civilians that happened in the vicinity of Vrhovine, in northwestern Croatia. Seven civilians were taken from their homes in the village of Dabar, exposed to unprecedented, savage torture and cruel execution. Forensic medicine experts revealed that victims were beaten with blunt objects, probably the butt end of rifles or high boots, stabbed with sharp objects as they were dying, and finally killed by gunshots. Their dead bodies were mutilated by cutting auricles and exposed to post-mortem humiliation. Events at Vrhovine have all the characteristics of crimes against humanity and inapprehensible breaches of the Geneva Convention at the very end of 20th century.  相似文献   
87.
Class I phosphoinositide 3-kinases (PI3Ks) are bifunctional enzymes possessing lipid kinase activity and the capacity to phosphorylate their catalytic and/or regulatory subunits. In this study, in vitro autophosphorylation of the G protein-sensitive p85-coupled class I(A) PI3K beta and p101-coupled class I(B) PI3K gamma was examined. Autophosphorylation sites of both PI3K isoforms were mapped to C-terminal serine residues of the catalytic p110 subunit (i.e. serine 1070 of p110 beta and serine 1101 of p110 gamma). Like other class I(A) PI3K isoforms, autophosphorylation of p110 beta resulted in down-regulated PI3K beta lipid kinase activity. However, no inhibitory effect of p110 gamma autophosphorylation on PI3K gamma lipid kinase activity was observed. Moreover, PI3K beta and PI3K gamma differed in the regulation of their autophosphorylation. Whereas p110 beta autophosphorylation was stimulated neither by G beta gamma complexes nor by a phosphotyrosyl peptide derived from the platelet-derived growth factor receptor, autophosphorylation of p110 gamma was significantly enhanced by G beta gamma in a time- and concentration-dependent manner. In summary, we show that autophosphorylation of both PI3K beta and PI3K gamma occurs in a C-terminal region of the catalytic p110 subunit but differs in its regulation and possible functional consequences, suggesting distinct roles of autophosphorylation of PI3K beta and PI3K gamma.  相似文献   
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The dinoflagellate Amylax triacantha is known to retain plastids of cryptophyte origin by engulfing the mixotrophic ciliate Mesodinium rubrum, itself a consumer of cryptophytes. However, there is no information on the fate of the prey's organelles and the photosynthetic performance of the newly retained plastids in A. triacantha. In this study, we conducted a starvation experiment to observe the intracellular organization of the prey's organelles and temporal changes in the photosynthetic efficiency of acquired plastids in A. triacantha. The ultrastructural observations revealed that while the chloroplast‐mitochondria complexes and nucleus of cryptophyte were retained by A. triacantha, other ciliate organelles were digested in food vacuoles. Acquired plastids were retained in A. triacantha for about 1 mo and showed photosynthetic activities for about 18 d when measured by a pulse‐amplitude modulation fluorometer.  相似文献   
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