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Notes: Analysis of 25 liver biopsy specimens and one autopsy specimen from 26 Japanese patients (23 women and three men) with idiopathic portal hypertension revealed findings that collectively appeared diagnostic for the condition. Changes in the portal tract included capillary dilatation, phlebosclerosis, and fibro-elastosis of the stroma. Many portal veins were dilated and had herniated into the surrounding hepatic parenchyma. Portal vein obliteration and loss of bile ducts were a rare complication. The acinar architecture was disturbed by: 1 capillary and necro-infiammatory bridging, mostly between portal tracts and terminal hepatic veins; 2 the formation of isolated megasinusoids in a random distribution; 3 displaced and abnormally large hepatic vein branches with or without phlebosclerosis and 4 slender, curved fibrous septa (hairline septa). Early nodular regeneration was found in 25% of the cases. Our review supports the contention that incomplete septal cirrhosis may be a late manifestation of idiopathic portal hypertension. It is not clear whether the biopsy findings in Japanese patients differ only in severity from those in western patients, or whether the conditions differ pathogenetically. Some histopathological findings in the Japanese cases, in particular the necroinflammatory changes, are difficult to reconcile with portal hypertension as a primary haemodynamic abn rmality.

Notes: Abstract We prove a generalization of Brouwer's famous fixed point theorem to discontinuous maps. The main result shows that for discontinuous functions on a compact convex domainX one can always find a pointx ∈X such that ∥x−f(x)∥ is less than a certain measure of discontinuity. Applications to artificial neural nets, economic equilibria and analysis are given.

Notes: Abstract Chlorinated hydrocarbons such as polychlorinated biphenyls (PCBs) and chlorinated insecticides have often been detected in Great Lakes fish-eating birds at concentrations that are correlated with greater than expected embryo mortality and reduced reproductive success. Blood from 111 known-age, adult Caspian terns (Sterna caspia) nesting in several regions of the upper Great Lakes was collected in 1990 to examine bioavailability of PCBs, to compare concentrations of PCBs among nesting locations, and to determine relationships between concentrations of PCBs and age, productivity, and colony site tenacity. PCBs, DDE, dieldrin, and trans-nonachlor were detected in all the samples. Concentrations of PCBs were, on average, 10, 100, and 250 times greater than those of DDE, dieldrin, and trans-nonachlor, respectively. Concentrations of PCBs were not correlated with age, and were greater in Caspian terns from Saginaw and Green Bays than in Caspian terns from the North Channel and Georgian Bay. Concentrations of PCBs and DDE were significantly correlated with one-another and their accumulation patterns were the most similar among all the chemicals studied. Patterns of organochlorines as determined by cluster analysis were most similar for the nearest nesting locations. The bioaccumulation of PCBs in Great Lakes Caspian terns appeared to be seasonal and did not vary with adult age. A significant negative correlation was observed between mean concentrations of PCBs by region and percent terns returning to natal region. Those populations which were likely to be affected by PCBs were those nesting in Green Bay and Saginaw Bay.

Notes: Abstract The Eurocollins (EC) and University of Wisconsin (UW) preservation solutions were compared in a rat liver transplant model. After hepatectomy, 48 rat livers were flushed with either EC or UW preservation solution and were randomly assigned to 1, 12, 24, and 30 h of preservation at 4°C, resulting in eight groups each containing six livers. Following preservation, orthotopic liver transplantation with reconstruction of the hepatic artery was performed. The efficacy of the preservation solution was assessed at 48 h post-transplantation by survival histological features and aspartate transaminase assay (AST) values. None of the rats survived 30 h of liver preservation with EC whereas five out of six rats did with UW preservation. After 24 h of liver preservation, three of the six rats in the EC group survived, compared to all six rats in the UW group. Histological evidence of severe ischemia was found in both groups in all but one survivor (UW, 24 h). After 12 h of EC preservation, one rat died within 48 h and severe ischemic changes were found in the remaining five rats. Among the rats with 12 h of UW preservation, only two out of six showed ischemic changes, and all six rats survived beyond 48 h. Without preservation (1 h), ischemic damage was found in two out of six rats in each group and all rats survived. The median AST values were higher in the EC groups than in the UW groups; the difference became significant after 12-h preservation (EC 900 IU/l versus UW 465 IU/l) and 24-h preservation (EC 5220 IU/l versus UW 631 IU/l). However, the median AST value in the five surviving rats whose livers had been preserved for 30 h in UW climbed to 1880 (950–2240) IU/l.. We conclude that UW solution provides better long-term preservation than EC solution. However, even with UW solution, the observed mortality, the severity of ischemic changes, and the pronounced increase in the median AST value cast doubt upon the safety of liver preservation beyond 24 h.

Notes: Abstract Populations of mink (Mustela vison) have declined in many areas of the world. Such declines have been linked to exposures to synthetic, halogenated hydrocarbons. In the Great Lakes region, mink are fewer in areas along the shore of the Great Lakes and their tributaries where mink have access to fish from the Great Lakes. Recently, there has been discussion of the relative merits of passage of fishes around hydroelectric dams on rivers in Michigan. A hazard assessment was conducted to determine the potential for adverse effects on mink, which could consume such fishes from above or below dams on the rivers. Concentrations of organochlorine insecticides, polychlorinated biphenyls (PCBs), 2,3,7,8-tetrachloridibenzo-p-dioxin equivalents (TCDD-EQ), and total mercury were measured in composite samples of fishes from above or below hydroelectric dams on the Manistee and Muskegon Rivers, which flow into Lake Michigan, and the Au Sable River, which flows into Lake Huron. Concentrations of organochlorine insecticides, PCBs, and TCDD-EQ were all greater in fishes from below the dams than those from above. Concentrations of neither organochlorine insecticides nor mercury in fishes are currently a risk to mink above or below the dams. All of the species of fishes collected from downstream of the dams contained concentrations of PCBs and TCDD-EQ, which represent a hazard to mink. The hazard index for PCBs was less than one for the average of all species from the upstream reaches of the Manistee and Au Sable Rivers, but not the Muskegon. The hazard index (concentration in fish/NOAEC) was greater than 1 for all of the species collected from below the dams, in all three rivers. The greatest hazard index was observed for carp (Cyprinus carpio) downstream on the Muskegon River. Because the concentrations of PCBs used in the hazard assessment were corrected for relative toxic potencies, the hazard ratios based on PCBs should be similar to those based on TCDD-EQ. This was found to be true. Thus, either total PCBs or TCDD-EQ could be used as the critical toxicant in the hazard assessment. However, if uncorrected concentrations of PCBs, expressed as Aroclors®, were used in the hazard assessment, the toxicity of the weathered mixture would have been underestimated by approximately five-fold, and, in that instance, TCDD-EQ would be the critical contaminant for the hazard assessment. The average maximum allowable percentage of fish from above the dams, which would result in no observable adverse effects of TCDD-EQ, was 70%. Based on the average TCDD-EQ concentrations in the fishes, an average of 8.6% of the diet could be made up of fishes from below dams on the rivers. The most restrictive daily allowable intakes were for carp on the Muskegon and steelhead trout (Onchorhyncus mykiss) on the Manistee Rivers. Only 2.7% of the diet could be made up of these two species from influenced portion of the Au Sable River, they would be exposed to 390 μg PCBs and 8.55 ng of TCDD-EQ per day, respectively (Giesy et al. 1994b). Thus, it would take 15.1 or 77 days for mink to receive their total annual dose of PCBs or TCDD-EQ, respectively. At least for chinook salmon, the critical contaminant for the purposes of hazard assessment would be total concentrations of PCBs. Consuming chinook salmon for as little as 2 weeks would deliver the annual allowable dose of PCBs to mink.

Notes: Abstract Fishes of the Great Lakes contain hazardous chemicals such as synthetic halogenated hydrocarbons and metals. These fish can move from the lakes into the Great Lakes tributaries of Michigan. In doing so, they transport concentrationsof contaminants which may represent a risk to wildlife. Concentrations of mercury (Hg), total polychlorinated biphenyls (PCBs), 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ), total DDT complex, aldrin, endrin, dieldrin, heptachlor, heptachlor epoxide, lindane, hexachlorobenzene, cis-chlordane, oxychlordane, endosulfan-I, methoxychlor, trans-chlordane, and trans-nonachlor were determined in composite samples of fishes from above and below Michigan hydroelectric dams, which separate the fishes which have access to the Great Lakes from fishes that do not. Mean concentrations of total PCBs, TCDD-EQ, DDT, and most of the other pesticides were greater in composite samples of six species of fishes from below than above the dams on the Au Sable, Manistee, and Muskegon Rivers. Concentrations of mercury, were the same or greater above the dams than below. However, this difference was statistically significant only on the Au Sable. Mercury concentrations ranged from less than 0.05 mg/kg to 0.73 mg Hg/kg, ww. Total concentrations of PCBs ranged from 0.02 to 1.7 mg/kg, ww. Concentrations of 2,3,7,8-tetrachlordibenzo-p-dioxin equivalents varied among fishes and locations. The concentrations of TCDD-EQ ranged from 2.4 to 71 μg/kg, ww, with concentrations in carp being the greatest. Concentrations of TCDD-EQ were greater than the concentrations which would be expected to occur, due solely to the presence of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and technical mixtures of PCBs.

Notes: Zusammenfassung Die Widderschnecke stellt ein ideales jagdbiologisches und populationsgenetisches Studienobjekt dar. An 81 Goldmedaillen — und 16 Widdern ohne Medaille Ostdeutschlands werden durch Rückmessung an der Schnecke Mittelwerte und Verteilungen altersabhängiger Leistungswerte errecht. Dabei ergab sich eine starke Überlappung in den Jugendklassen, die eine sichere Differenzierung nach der wirklichen Ernteleistung fast nicht ermöglicht. Diese Aussage wird durch Prognosewerte des Bestimmtheitsmaßes gestützt. Über eine Änderung der bisherigen Abschußstrategie wäre nachzudenken.

Notes: Zusammenfassung Die Stückelung von Wachstumsabläufen bei den Cerviden in kleinere, biologisch bedingte Zeitintervalle ermöglicht den rationellen Einsatz statistischer Taschenrechner (lineare Korrelations- und Regressionsrechnung). Dadurch ist es auch dem biometrisch weniger Kundigen möglich, eigene Beobachtungen und Ergebnisse mathematisch-statistisch selbständig zu formulieren und zu interpretieren. Am Beispiel von 243 Abwürfen Rothemühler Bronzemedaillen-Hirsche im Alter von 2 bis 16 Jahren konnte mit der Altersintervallbildung eine Aussagenverbesserung bei der Stangenlänge im Vergleich zur Gesamtauswertung erreicht werden. So wurde in der Jugend ein sehr hoher, ab Alter 8 dagegen gar kein Zusammenhang mehr zwischen Alter und Stangenlänge nachgewiesen. Innerhalb eines kleinen Gebietes wäre somit die große Variabilität der Stangenlänge im höheren Alter als genetische Veranlagung der Einzelhirsche anzusehen, welche in der Jugend durch den schnellen Wachstumsprozeß überlagert wird. Die vorgeschlagene Intervallbildung altersabhängigen Wachstums bietet eine Reihe von Vorteilen. Sie gelten nicht nur für den Rothirsch, sondern biologisch allgemein.

Notes: Abstract At three locations in NE-Bavaria (Central Europe), aerosol particles were collected in five size fractions with a cascade impactor. The water soluble part of each fraction was analyzed for major ions and strong, weak and neutralizing acidities. For reliable determination of these categories of acidity, a comparison between different methods was initially performed. Further study revealed a distinct difference in amount and character of the acidity between fine (Dp 〈 1.35 μm) and coarse (Dp 〉 4.05 μm) particles. Fine particles always reacted acidic and their acidity was mainly due to strong acids. Concentrations were highest in polluted urban air, where additional weak organic acids were present in fine particles. The in situ pH's were calculated as pH 1...2 for these particles at all sampling sites. Coarse particles were only slightly acidic, with a mean in situ pH 5.5...6.5. Their acidity was mainly caused by weak acids, especially hydroxilized metal ions dominated by Al.