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Over the past 10 years, arteriography has become a well-established technique for the diagnosis of acute lower gastrointestinal bleeding, but not particularly for rectal bleeding. However, to the authors' knowledge, the technique of middle hemorrhoidal artery embolization has rarely been reported in the literature. In the present report, three patients with life-threatening rectal bleeding are presented, which was controlled by superselective embolization of the middle hemorrhoidal artery or selective embolization of the internal iliac artery as a last resort.  相似文献   
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In summary, we have described two patients with CRMO and psoriasis, and have reviewed the musculoskeletal manifestations associated with pustular eruptions of the palms and soles. In view of the frequent occurrence of PPP in patients with CRMO, we suggest that the occurrence of psoriasis in our two patients is more than coincidence, and that noninfectious, inflammatory lesions of bone may be another musculoskeletal manifestation of psoriasis. This rare association, as well as the association of PPP with disorders associated with new bone formation, may shed new insights on the relatively common finding of periosteal elevation associated with psoriatic arthritis and the occasional severe juxta-articular osteolytic destructive bone lesions seen in psoriatic arthritis.  相似文献   
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High doses of sodium saccharin, a non-genotoxic chemical, lead to the formation of silicate-containing precipitate and microcrystals in urine of male rats. Differences in urinary protein, pH, sodium and other factors affect silicate-containing precipitate and microcrystal formation as well as the bladder effects of sodium saccharin. Total urinary silicon concentration (mostly soluble) in sodium saccharin-fed rats is similar to or lower than the concentration in control rats. Binding of saccharin to male rat urinary proteins was demonstrated by equilibrium-gel filtration. We propose that by binding to urinary proteins under appropriate conditions, saccharin produces a nidus for the formation of silicate-containing precipitate and crystals. These appear to be cytotoxic to the superficial bladder epithelium, with cell death resulting in regenerative hyperplasia. Factors that influence the formation of these silicate-containing materials might provide a rationale for sex, species, dose and dietary differences in response to sodium saccharin.  相似文献   
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In previous reports weanling female rats fed a high-fat diet had a delayed response to hypothalamic knife cuts. In the present report similar cuts in similar rats fed a standard low fat diet became overweight without delay, suggesting that dietary fat is a critical variable in juvenile onset obesity. Adult rats given knife-cuts comparable to those in the weanlings gained weight far more rapidly and achieved higher weights than did those cut as weanlings, suggesting that appetite modulating axons can develop after weaning. Finally, group vs single housing did not influence the age of onset or the magnitude of knife-cut obesity.  相似文献   
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Ultrastructural study of microsporidian invasion into cells   总被引:1,自引:0,他引:1  
Summary Nosema michaelis spores were primed to discharge extracellularly or into culture medium 199 containing ascites leukemia EL4 cells, mouse macrophages, neuroblastoma C1300 adapted to ascites, human red blood cells, and blue crab epithelial cells and hemocytes.Before discharge, the polar tube has a single membrane enveloping a glycoprotein-like matrix. After extrusion, there are two membrane envelopes surrounded by a glycoprotein sheath. This sheath is silver methenamine negative, trypsinsensitive, has low solubility to 1% SDS treatment, and binds ferritin-conjugated concanavalin A.Before spore discharge, the sporoplasm is dispersed, uncompartmentalized by any membrane and exterior to the extrusion apparatus. After passage through the extrusion tube, the sporoplasm ends up in vesicle formed at the end of extruded tube. The sporoplasm nucleus maintains its integrity during extrusion; both the cytoplasm and nuclear components of the discharged sporoplasm are compartmentalized within membranes. After 15–20 min within the host cytoplasm, the sporoplasm shows obvious cytoplasmic reorganization and endoplasmic reticulum synthesis.Within the host cell, the sporoplasm is surrounded by two envelopes, the outer of which appears continuous with the polar tube sheath. Two envelopes surround the parasite when it is injected into extracellular medium, into human red blood cells, or into ascites leukemia EL4 cells. One envelope is lost when the sporoplasm is injected into normal host cells such as blue crab hemocytes and epithelial cells.A fibrous corona surrounds the sporoplasm in ascites leukemia EL4 cells, neuroblastoma C1300 or mouse macrophages. This corona is believed to be host reaction material since it is absent when parasites are injected into blue crab gut epithelial cells and hemocytes, into extracellular medium, or into human red blood cells.Supported by training grant from the National Institutes of Health A 10092. Special thanks are extended to Prof. William Trager.  相似文献   
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