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11.
Acute kidney injury is common in patients with liver disease and associated with significant morbidity and mortality. Besides bacterial infections, fluid loss, and use of nephrotoxic drugs AKI in liver disease may be triggered by tubular toxicity of cholephiles. Cholemic nephropathy, also known as bile cast nephropathy, supposedly represents a widely underestimated but important cause of renal dysfunction in cholestasic or advanced liver diseases with jaundice. Cholemic nephropathy describes impaired renal function along with characteristic histomorphological changes consisting of intratubular cast formation and tubular epithelial cell injury directed towards distal nephron segments. The underlying pathophysiologic mechanisms are not entirely understood and clear defined diagnostic criteria are still missing.This review aims to summarize (i) the present knowledge on clinical and morphological characteristics of cholemic nephropathy, (ii) available preclinical models, (iii) potential pathomechanisms especially the potential role of bile acids, and (iv) future diagnostic and therapeutic strategies for cholemic nephropathy. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.  相似文献   
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Summary The lymphatic organization and its relationship to the vascular system in the rat small intestine was studied by scanning electron microscopy of corrosion casts and freeze-fractured tissues, and by light microscopy of injected preparations. The villus possessed 3–10 or more central lacteals depending upon the villous width. The lacteals in each villus possessed interconnections between adjacent ones and were surrounded externally by the villous capillary network. At the villous base, the lacteals fused and formed a wide sinus, from which 2 or 3 lymphatics descended and led into the submucosal ones. In the muscularis externa there was a coarse lymphatic network which, together with the submucosal one, drained into collecting lymphatics continuous with the mesenteric ones. The central lacteals and the sinus were lined with thin endothelial cells with cytoplasmic leaves interdigitating with those of adjacent ones. There were tissue channels in the villous interstitial space, which opened through the gaps between the lymphatic endothelial cells into the central lacteals.The voluminous lacteals in the villi suggest their great potential for lymph formation. The existence of collecting lymphatics with valves in the muscularis externa suggests that contraction of the layer is involved in transporting lymph towards the efferent lymphatics.  相似文献   
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Summary The three-dimensional architectures and the regional differences of the vascular system in the mucosa of the hamster stomach were revealed by scanning electron microscopy of corrosion casts. In the forestomach, the vascular network spreads two-dimensionally in a thin lamina propria. In the corpus and the antrum, the capillaries in the thick lamina propria are well developed, extending three-dimensionally along the gastric pits and glands. In the corpus, the submucosal arteries enter the lamina propria to become ascending capillaries, which project toward the top of the lamina propria and anastomose to create a capillary network beneath the mucosal epithelium. A subepithelial capillary is much wider in diameter than an ascending capillary and is, therefore, a sinusoid capillary. Subepithelial capillaries join descending venules, which are less numerous than the ascending capillaries. Near the gastric lumen, the capillaries in the corpus can be classified into two types: arched type in the cephalic (upper) region and honeycomb type in the caudal (lower) region. In the antrum, the submucosal arterial plexus is less well developed than that in the corpus. The mucosal aspect of the corrosion cast shows many clumps, formed by a unit of capillary network. Functional significances of different vascular architectures in the gastric mucosa of the forestomach, corpus, and antrum are discussed.This study was supported in part by grants from the Research Fund of the Ministry of Education, Science, and Culture, Japan  相似文献   
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15.
鼻腔粘膜对净化空气,调节空气温度和湿度具有重要作用。本文采用甲基丙烯酸甲酯制作血管铸型,通过扫描电镜对人鼻粘膜微血管三维构筑进行观察。  相似文献   
16.
In South Africa, gracilarioid red algae have been collected as wash-up to be dried and sold for agar extraction for at least 50 years. Despite much research, there is currently no commercial mariculture of the algae locally although this has been carried out in neighboring Namibia for a number of years. The industry is traditionally confined to Saldanha Bay on the west coast, although small wash-ups of Gracilariopsis longissima have been collected in nearby St Helena Bay. In Saldanha Bay, wash-ups of Gracilaria. gracilis have been very sporadic over the last few decades, with human alteration of the bay configuration possibly responsible for an initial major decline in 1974. This unpredictability in the amounts of wash-up has made the industry unstable and increasingly unprofitable. We compiled the results of previous surveys (some unpublished) of gracilariod populations in St Helena Bay and the Saldanha-Langebaan sytem, and re-surveyed these populations to examine long-term fluctuations. In Saldanha Bay and Langebaan Lagoon, standing stock of G. gracilis was estimated at 538 tons fresh weight and 71 tons fresh weight respectively. Less than 4 tons of gracilarioids are estimated to remain in St Helena Bay. We discuss the fluctuations in biomass and distribution of these South African gracilarioid populations.  相似文献   
17.
BACKGROUND: Corrosion casting and immunohistochemical staining with anti‐alpha smooth muscle actin and anti‐CD34 was utilized to demonstrate the capillary plexus and venous system in control and malformed mouse hearts. METHODS: Outflow tract malformations (e.g., double outlet right ventricle, transposition of the great arteries, and common truncus arteriosus) were induced in progeny of pregnant mice by retinoic acid administration at day 8.5 of pregnancy. RESULTS: Although control hearts exhibited areas in which capillaries tended to be oriented in parallel arrays, the orientation of capillaries in the respective areas of malformed hearts was chaotic and disorganized. The major branch of a conal vein in control hearts runs usually from the left side of the conus to its right side at the root of the pulmonary trunk and opens to the right atrium below the right auricle; thus, it has a curved course. On the other hand, a conal vein in malformed hearts courses from the left side or from the anterior side of the conus and tends to traverse straight upwards along the dextroposed aorta or along the aortopulmonary groove with its proximal part located outside of the heart. Other cardiac veins in outflow tract malformations are positioned in the same locations as in control hearts. CONCLUSIONS: We postulate that the changed location of the conal vein and disorganized capillary plexus result from malformed morphogenesis of the outflow tract and/or a disturbed regulation of angiogenic growth factor release from the adjacent environment. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
18.
Shed antler hunting (i.e., collecting cast cervid antlers) has increased in popularity during the past decade, but little is known about how this recreational activity affects ungulate movements and space use. We placed geographic positioning system (GPS)-collars on 133 female and male bighorn sheep (Ovis canadensis), bison (Bison bison), and mule deer (Odocoileus hemionus) to quantify their movements and space use during shed antler hunts compared with those behaviors during helicopter surveys in Utah, USA, from 2012 to 2015. For each species, we calculated means and 95% confidence intervals for distance moved during 90-minute segments (16 points/day) pre-event (control, 7 consecutive days prior to event), event (1–2 days), and post-event (7 consecutive days after event) for shed antler hunts and helicopter surveys. We also compared use of space for each species during these events. Female bighorn sheep did not increase distance moved or substantially change space use during shed antler hunts and helicopter surveys. Male bighorn sheep increased distance moved 41% on average during shed antler hunts and by 2.02 times during helicopter surveys but did not change space use during those events. Female bison increased distance moved 15% on average during shed antler hunts and 30% during helicopter surveys. Mule deer increased distance moved and altered space use the most during shed antler hunts; females increased distance moved 97%, and 54% of females moved a mean distance of 742 ± 642 (SD) m (range = 9–3,778 m) outside of their home ranges during those hunts for a mean of 9.2 ± 9.4 hours (range = 1.5 to 41 hr). Male mule deer increased distance moved by 2.10 times on average during shed antler hunts, and 82% of males moved a mean distance of 1,264 ± 732 m (range = 131–3,637 m) outside of their home ranges during those hunts for a mean of 12.6 ± 7.6 hours (range = 4.5–33 hr). Our results provide timely information about how legal shed antler hunting affects movements and space use of female and male ungulates, especially mule deer, and can guide the conservation of ungulate populations and their habitat. © 2021 The Wildlife Society.  相似文献   
19.
A series of alkyl, alkoxyl, and alkylthio substituted A–π–D–π–A type nonfullerene acceptors (NFAs) IDTCN‐C , IDTCN‐O, and IDTCN‐S are designed and synthesized. The introduction of a lateral side chain at the outer position of the π bridge unit can endow the terminal moiety with a confined planar conformation due to the steric hindrance. Thus, compared with nonsubstituted NFA ( IDTT2F ), these acceptors tend to form favorable face‐on orientation and exhibit strong crystallinity as verified with grazing‐incidence wide‐angle X‐ray scattering measurement. Moreover, the variation of side chain can significantly change the lowest unoccupied molecular orbital (LUMO) energy level of acceptors. As state‐of‐the‐art NFAs, a power conversion efficiency of 13.28% (Voc = 0.91 V, Jsc = 19.96 mA cm?2, and FF = 73.2%) is obtained for the as‐cast devices based on IDTCN‐O , which is among the highest value reported in literature. The excellent photovoltaic performance for IDTCN‐O can be attributed to its slightly up‐shifted LUMO level and more balanced charge transport. This research demonstrates side chain engineering is an effective way to achieve high efficiency organic solar cells.  相似文献   
20.
Two new species of Lirula (L. japonica and L. exigua) on Abies mariesii collected in subalpine areas of northern Japan are described as members of Rhytismatales, Discomycetes. Lirula japonica causes needle cast in fir, but L. exigua seems to occur on the needles of physically damaged twigs. Morphological characteristics of both species are discussed.  相似文献   
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