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Radio-isotopic techniques may be useful in diagnosis and staging of chronic diffuse liver diseases. Liver angioscintigraphy (LAS) and per-rectal portal scintigraphy (PRPS) are at well discriminating portal hypertension (PHT), very early cirrhosis hemodynamic failure and compensatory arterialisation of liver perfusion. Supplied information is related to PHT, liver morphology and mesenchimal activity in liver, spleen and bone marrow. Correlation of LAS and PRPS may diagnose installing of PHT earlier than any actual morphologic imagistic method. Our experience (after more than 300 PRPS and 500 LAS) suggests that PHT and portal-cave shunts (PCS) may be classified in five functional stages. These five patterns (types) are characteristic for portal dynamics, supporting disease staging and follow-up of evolution to cirrhosis. All five dynamics may be assessed by PRPS and LAS. Scintigraphic techniques also explore portal thromboses, perfusion differences between the lobes of cirrhotic liver, betablockers effect in PHT, earliest stages of PHT, malignant tumours occurring on cirrhosis, the different characteristics of alcoholic liver comparing to viral etiology.  相似文献   
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Hypothalamic feeding circuits have been identified as having innate synaptic plasticity, mediating adaption to the changing metabolic milieu by controlling responses to feeding and obesity. However, less is known about the regulatory principles underlying the dynamic changes in agouti-related protein (AgRP) perikarya, a region crucial for gating of neural excitation and, hence, feeding. Here we show that AgRP neurons activated by food deprivation, ghrelin administration, or chemogenetics decreased their own inhibitory tone while triggering mitochondrial adaptations in neighboring astrocytes. We found that it was the inhibitory neurotransmitter GABA released by AgRP neurons that evoked this astrocytic response; this in turn resulted in increased glial ensheetment of AgRP perikarya by glial processes and increased excitability of AgRP neurons. We also identified astrocyte-derived prostaglandin E2, which directly activated — via EP2 receptors — AgRP neurons. Taken together, these observations unmasked a feed-forward, self-exciting loop in AgRP neuronal control mediated by astrocytes, a mechanism directly relevant for hunger, feeding, and overfeeding.  相似文献   
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We present a 12‐year‐old immunocompetent girl with hepato splenic cat‐scratch disease (CSD). Her sole inaugural complaint was isolated epigastric pain. She fully recovered, with normalized abdominal CT scan following 2 weeks course of Azythromycin®. CSD should be included in differential diagnosis in children with epigastric pain, especially in those with domestic pets.  相似文献   
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Background: Dental biofilms contain a protein that inhibits mammalian cell growth, possibly lysine decarboxylase from Eikenella corrodens. This enzyme decarboxylates lysine, an essential amino acid for dentally attached cell turnover in gingival sulci. Lysine depletion may stop this turnover, impairing the barrier to bacterial compounds. The aims of this study are to determine biofilm lysine and cadaverine contents before oral hygiene restriction (OHR) and their association with plaque index (PI) and gingival crevicular fluid (GCF) after OHR for 1 week. Methods: Laser‐induced fluorescence after capillary electrophoresis was used to determine lysine and cadaverine contents in dental biofilm, tongue biofilm, and saliva before OHR and in dental biofilm after OHR. Results: Before OHR, lysine and cadaverine contents of dental biofilm were similar and 10‐fold greater than in saliva or tongue biofilm. After 1 week of OHR, the biofilm content of cadaverine increased and that of lysine decreased, consistent with greater biofilm lysine decarboxylase activity. Regression indicated that PI and GCF exudation were positively related to biofilm lysine after OHR, unless biofilm lysine exceeded the minimal blood plasma content, in which case PI was further increased but GCF exudation was reduced. Conclusions: After OHR, lysine decarboxylase activity seems to determine biofilm lysine content and biofilm accumulation. When biofilm lysine exceeds minimal blood plasma content after OHR, less GCF appeared despite more biofilm. Lysine appears important for biofilm accumulation and the epithelial barrier to bacterial proinflammatory agents. Inhibiting lysine decarboxylase may retard the increased GCF exudation required for microbial development and gingivitis.  相似文献   
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Recent studies have highlighted a group of 4-repeat (4R) tauopathies that are characterised neuropathologically by widespread, globular glial inclusions (GGIs). Tau immunohistochemistry reveals 4R immunoreactive globular oligodendroglial and astrocytic inclusions and the latter are predominantly negative for Gallyas silver staining. These cases are associated with a range of clinical presentations, which correlate with the severity and distribution of underlying tau pathology and neurodegeneration. Their heterogeneous clinicopathological features combined with their rarity and under-recognition have led to cases characterised by GGIs being described in the literature using various and redundant terminologies. In this report, a group of neuropathologists form a consensus on the terminology and classification of cases with GGIs. After studying microscopic images from previously reported cases with suspected GGIs (n = 22), this panel of neuropathologists with extensive experience in the diagnosis of neurodegenerative diseases and a documented record of previous experience with at least one case with GGIs, agreed that (1) GGIs were present in all the cases reviewed; (2) the morphology of globular astrocytic inclusions was different to tufted astrocytes and finally that (3) the cases represented a number of different neuropathological subtypes. They also agreed that the different morphological subtypes are likely to be part of a spectrum of a distinct disease entity, for which they recommend that the overarching term globular glial tauopathy (GGT) should be used. Type I cases typically present with frontotemporal dementia, which correlates with the fronto-temporal distribution of pathology. Type II cases are characterised by pyramidal features reflecting motor cortex involvement and corticospinal tract degeneration. Type III cases can present with a combination of frontotemporal dementia and motor neuron disease with fronto-temporal cortex, motor cortex and corticospinal tract being severely affected. Extrapyramidal features can be present in Type II and III cases and significant degeneration of the white matter is a feature of all GGT subtypes. Improved detection and classification will be necessary for the establishment of neuropathological and clinical diagnostic research criteria in the future.  相似文献   
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