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1. Experiments have been performed in sheep to determine the contribution of lymph formed within a lymph node to the total protein output in lymph leaving the node. 2. The lymphatic duct leaving the popliteal lymph node was cannulated and the protein and lymphocyte output in efferent lymph determined. The afferent lymph flow to the popliteal node was then diverted and lymph formed only within the lymph node collected from the efferent cannula. It appeared from the results that the popliteal lymph node forms lymph at the rate of approximately 1 ml. per hour and may contribute 30-50% of the protein output observed in efferent lymph. 3. The importance of lymph formation within the lymph node varied between nodes found in different regions of the body. This was due in part to the different protein concentrations in the afferent lymph to the different nodes. 4. A positive correlation was found between the protein and lymphocyte concentrations in efferent lymph from the popliteal lymph node in seven out of eleven sheep and in lymph formed within the popliteal lymph node in two out of three sheep. It is suggested that this relationship may be due to an increased transfer of plasma proteins through the post-capillary venules in the lymph node accompanying the continual traffic of lymphocytes across the wall of these vessels. The results indicated that the protein transfer across the post-capillary venules was not an indiscriminate transfer of plasma per se but a selective transport from the blood plasma compartment based on molecular size. 相似文献
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The degeneration of the substantia nigra that characterises Parkinson's disease may cause an alteration in sensitivity of striatal dopamine receptors. The development of denervation supersensitivity has been held to be responsible for some of the effects of chronic levodopa therapy. The rotating rodent is an animal model commonly used to study the phenomenon of striatal dopamine receptor supersensitivity, and to investigate drugs which may prove to be beneficial in the treatment of Parkinson's disease. We have investigated as to whether long-term oral administration of levodopa to mice with unilateral destruction of striatal dopaminergic nerve terminals influences dopaminergic receptor denervation supersensitivity as judged by the circling response following systemically administered levodopa. It does not do so and the relevance of these findings to the treatment of Parkinson's disease is discussed. 相似文献
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Aspergillus terreus infection limited to the L1-2 disk space and first and second lumbar vertebrae developed in a patient not predisposed to invasive aspergillosis. The observation of morphologically distinct secondary spores (aleuriospores) on microscopic examination of open biopsy specimens permitted a preliminary identification of A terreus, which was confirmed by culture. The infection was eradicated with amphotericin B in a total dose of 3 gm. Aspergillus terreus is usually a saprophyte. The present case and four others collected from the literature establish this species as an invasive pathogen. 相似文献
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