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41.
Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management.  相似文献   
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Macropotrema pertinax gen. et sp. nov. (Digenea: Paramphistomidae) is described from the caecum of the macropodid marsupial Macropus agilis (Gould, 1842) from northern Australia. The new genus is characterised as follows: ventro-terminal acetabulum bearing many papillae; oral sucker with constriction and paired diverticula; oesophagus with muscular bulb; cirrus sac and genital sucker absent; testes symmetrical, unlobed, preovarian; Laurer's canal opening anterior to excretory pore. The genus is placed in the subfamily Pseudodiscinae N?smark, 1937. At the point where the worm attaches to the caecal wall of the host, the entire mucosa is destroyed and there is an inflammatory cell infiltration in the intact mucosa surrounding the attachment site.  相似文献   
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BACKGROUND: A high incidence of schizophrenia has been reported in individuals with sex chromosome aneuploides (SCAs), and extra-X aneuploidy appears to adversely affect neurodevelopment. We previously examined neurodevelopment in SCA subjects with structural magnetic resonance imaging (MRI) of the brain. We present an XXY subject who subsequently developed schizophrenia. Further examination of the MRI data was undertaken. METHODS: Graphs of MRI-determined regional brain to whole brain volume proportions and cerebral asymmetry indexes were generated for Klinefelter (n = 10) and male control subjects (n = 25) to allow inter-individual comparisons. RESULTS: The index case had reversed prefrontal and temporal lobe asymmetries, and these findings were more marked than in any other subject. CONCLUSIONS: It has been suggested that a genetic locus for schizophrenia may be found on the X chromosome and that the gene(s) concerned are implicated in the development of normal cerebral asymmetries. This case supports these arguments.  相似文献   
44.
Gentamicin interaction with Pseudomonas aeruginosa cell envelope.   总被引:12,自引:2,他引:12       下载免费PDF全文
Gentamicin, an aminoglycoside antibiotic known to inhibit protein synthesis, had a detrimental effect on the integrity of the cell wall of Pseudomonas aeruginosa ATCC 9027 (a susceptible strain) as shown by electron microscopy using negative-staining, thin-sectioning, and freeze-fracture techniques. The disruption occurred in a sequential manner, moving from the outer membrane to the inner membrane, and could result in lysis of the cell. During this process the outer membrane lost 34% of its total protein and 30% of its lipopolysaccharide (measured as 2-keto-3-deoxyoctonate) upon exposure to 25 micrograms of gentamicin per ml for 15 min. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the outer membrane proteins showed altered banding patterns after exposure to gentamicin. Atomic absorption spectrophotometry revealed a decrease in magnesium and calcium content (18 and 38%, respectively) in the cell envelopes after gentamicin treatment. It is proposed that gentamicin displaces essential metal cations within the outer membrane, consequently destabilizing and extracting organic constituents. Small transient holes are thereby produced which make the outer membrane more permeable to the antibiotic and which expose the protoplast to high concentrations of gentamicin. This membrane effect may contribute to the effects of protein synthesis inhibition during the killing process.  相似文献   
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64Cu(II) is extensively absorbed and excreted, mainly in the faeces, when applied to the skin of rats as complexes with (a) salicylate in ethanol with dimethylsulphoxide and glycerol or (b) phenylbutazone in dimethyl sulphoxide and glycerol, previously found to be anti-inflammatory. 64Cu distribution paralleled that observed after administering aqueous 64Cu-salicylate i.m. It is concluded that copper(II) can pass rapidly through the dermal barriers when applied with an appropriate cupriphore and presented in a medium with low water content.  相似文献   
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