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21.
In previous studies it has been demonstrated that a decline of plasma calcium concentration accounts for the decrease of phosphate reabsorption in thyroparathyroidectomized (TPTX) rats undergoing phosphate loading.Microinfusion studies were performed in TPTX rats in order to discriminate between a systemic effect of calcium an a direct renal effect.Thyroparathyroidectomized animals were infused with a phosphate solution continuously. When plasma calcium concentration fell below 1.30 mmol/l, proximal convoluted tubules were microinfused with a phosphate tracer solution for 42 min. After 18 min a calcium chloride-containing solution was applied superficially (superfused) to the area of the microinfused tubule. This elevation of peritubular calcium concentration led to an immediate increase of phosphate reabsorption up to 12% of the microinfused phosphate load within 24 min.In another series of experiments, the calcium specific ionophore A 23187 — a substance which is known to increase intracellular calcium — was superfused on the microinfused tubule. This resulted again in an increase of fractional phosphate reabsorption of about 15% after 24 min. In contrast, when calcium chloride-free as well as ionophore-free solutions were superfused fractional phosphate reabsorption decreased (7%).From these data we conclude that 1. calcium has a direct renal effect on phosphate reabsorption in the absence of parathyroid hormone and 2. intracellular calcium appears to be a major parameter in the regulation of renal phosphate transport under these conditions.This study was supported by Dr. Legerlotz StiftungParts of this study were presented at the fall meeting of the Nephrologische Gesellschaft in Bonn, 1977 and at the spring meeting of the Deutsche Physiologische Gesellschaft in Göttingen, 1978  相似文献   
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BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms.  相似文献   
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The Xenopus oocyte nucleus (GV) is a storehouse for a large number of proteins that are used during early development. We have cloned and characterized a cDNA coding for a maternal gene product that is localized in the GV and then becomes highly enriched in the nuclei of the central nervous system (CNS) of tadpoles and adult frogs. This cDNA (xlgv7) is 2.1 kb and hybridizes to a 2.4-kb RNA species on Northern blots. Southern blots of genomic DNA suggest that this gene is a member of a multigene family. The cDNA sequence reveals a long open reading frame (ORF) of 1773 nucleotides, with a putative nuclear targeting signal (Glu Arg Arg Lys Lys Lys Thr) at the extreme carboxyl terminus and an internal histidine (His)-rich region with a repeated conserved amino acid sequence between His pairs. The significance of this region is unclear, but the protein is a DNA-binding protein, and it is possible that this region is involved in this function. The xlgv7 protein also possesses a putative nucleotide-binding consensus sequence that is similar to the bacterial RecA and RecB and yeast RAD proteins. Protein xlgv7 exists as several isotypes that exhibit developmental and cell-specific changes during development. Northern blot analysis of the abundance of the xlgv7 mRNA shows an accumulation following neural induction at stages 15-16. There is a transient expression of the mRNA in the gut of tadpoles. In the adult, the mRNA is highly enriched in the brain and is absent or in very low abundance in other tissues. Immunohistochemical analysis of the protein shows that the protein is localized in the nuclei of the brain cells. We conclude that the xlgv7 gene product is a maternal protein that may serve several important functions, one of which may be in the development and maintanance of the CNS.  相似文献   
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Does neuroretinitis rule out multiple sclerosis?   总被引:1,自引:0,他引:1  
Neuroretinitis, a form of optic neuritis, is characterized by papillitis and a stellate macular exudate, or "macular star." The star implies the presence of a disc vasculopathy and secondary leakage of lipoproteinaceous material into the macula. Demyelinating optic neuritis would not be expected to produce a secondary macular exudate. We reviewed the literature on the risk of multiple sclerosis developing in a patient after an attack of optic neuritis, and rarely found a comment on the presence of a macular star. We then reviewed two series of 40 patients who had neuroretinitis and added ten patients of our own. Signs of multiple sclerosis had not developed in the 13 patients contacted retrospectively, nor in the patients followed up prospectively. We also noted that in our patients, neuroretinitis may be accompanied by other neurologic manifestations; neuroretinitis may be bilateral and may be staggered; papillitis may present without a macular star, only to have typical exudates develop up to two weeks later; and the macular exudate may take up to 12 months to resolve. We suggest that patients who demonstrate acute papillitis with a normal macula be reevaluated within two weeks for the development of a macular star. Its presence militates strongly against the subsequent development of multiple sclerosis.  相似文献   
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We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss...  相似文献   
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Neurosurgical Review - In the context of hydrocephalus, there are a multitude of therapeutic options that can be explored in order to improve patient outcomes. Although the peritoneum is the...  相似文献   
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Annals of Surgical Oncology - The aim of this study was to report outcomes following percutaneous microwave and cryoablation of lung metastases from adenoid cystic carcinoma (ACC) of the head and...  相似文献   
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