Portal segmental

The portal segments and the hepatovenous segments are, however, subject to considerable individual variations with respect to their size and the position of their boundaries. This point must always be considered in cases of hepatectomy. For this reason there is, as yet, no general agreement about the designation of the segments. (16, 28, 70)... 

Kogure K, Kuwano H, Fujimaki N, et al. (2000) Relation among portal segmentation, proper hepatic vein, and external notch of the caudate lobe in the human liver. Ann Surg 231 223-228... 

Bile is produced continuously by the liver bile salts are secreted by the hepatocytes and the water, sodium bicarbonate, and other inorganic salts are added by the cells of the bile ducts within the liver. The bile is then transported by way of the common bile duct to the duodenum. Bile facilitates fat digestion and absorption throughout the length of the small intestine. In the terminal region of the ileum, the final segment of the small intestine, the bile salts are actively reabsorbed into the blood, returned to the liver by way of the hepatic portal system, and resecreted into the bile. This recycling of the bile salts from the small intestine back to the liver is referred to as enterohepatic circulation. 

This theory was further explored in an anaesthetised pig model, which facilitated portal vein and bile sampling [86], However, the hepatic extraction ratio and the biliary clearance of fexofenadine were unaffected by verapamil in the pig model. The question as to why verapamil/ketoconazole increase the fraction absorbed (i.e. based on appearance kinetics) and yet the fraction absorbed estimated on the basis of disappearance kinetics (i.e. /err) for the intestinal segment appears unchanged remains to be explored and most likely reflect multiple interplay between absorptive and efflux drug transporters in the intestinal tissue. 

There are many different procedures used for pancreas transplantation, and there is no one standard protocol used in all transplant centers. The important considerations, however, are that the arterial blood flow supply to the pancreas and duodenal segment, and venous outflow from the pancreas via the portal vein should be adequate. The recipient s right common or external iliac artery is used to restore vascularization of the artery in the pancreas. The Y graft of the tissue is anastomosed end-to-side and the venous vascularization is performed either systemically or portally, but mostly it is done with systemic venous drainage. 

By addressing issue 9 of how isoelectronic chemical reactivities enter the total energy of interaction of two disjoint, nonoverlapping systems [50], we show in Sect. 8 how contact can be made between chemical reactivities and the initial segment of, or portal to, the reaction pathway. As by-products, a clear definition of the chemical stimuli which couple to the reactivity indices, the chemical responses, and a clear definition of dynamic as well as static chemical reactivities emerge, resolving issues 7 and 8, respectively. 

The liver can be divided into eight segments, which are determined by the blood supply from the portal vein. 

Couinaud C. Liver anatomy portal (and suprahepatic) or biliary segmentation. Dig Surg 1999 16 459-467. 

Van Leeuwen, M.S., Noordzij, J., Fernandez, M.A., Hennipman, A., Feld-berg, MA.M., Dillon, E.H Portal venous and segmental anatomy of the right hemiliver observations based on three-dimensional spiral CT rendering Amer. X Roentgenol. 1994 163 1395—1404... 

Detection of portal hypertension (see chapter 14) is of crucial importance in the diagnosis of cirrhosis. The sensitivity is 76-80% and the specificity 100%. The following findings may be present (7.) dilation of the portal vein (> 1.5 cm), (2.) calibre leap between the extra-and intrahepatic segments of the portal vein in the porta hepatis (so-called portal vein amputation), (3.) dilation of the splenic vein (>1.5 cm), (4.) widening of the hep-... 

Compression or thrombosis of the splenic vein = segmental portal hypertension... 

Lenthall, R., Kane, PA., Heaton, N.D., Karani, J.B. Segmental portal hypertension due to splenic obstruction imaging findings and diagnostic pitfalls in four cases. Clin. Radiol. 1999 54 540—544... 

The location of the atoms that protrude into the solvent clearly points to this segment of ALBP as a favored ligand entry point. Near the alleged portal in ALBP, P2, and IFABP is a phenylalanine side chain. Crystallographic studies of the apo, the stearate, and the oleate complex of ALBP revealed that one side chain, Phe-57, was located in different positions in the different crystal forms depending on the presence of ligand (Xu et ai, 1993). The comparisons are shown in stereo in Fig. 11. Similarly in the P2 study, there are three molecules in the asymmetric unit. Two have Phe-57 in one conformation one molecule has it in another conformation that differs primarily by a Xi change. 

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