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Summary Mature growth-phase internodes of Alaska paper birch (Betula resinifera) are preferred by the snowshoe hare (Lepus americanus) over juvenile growth-phase internodes due to the low food value of the latter. While the mature over juvenile preferencec cannot be explained by the levels of inorganic nutrients or gross chemical fractions (resins or phenols), it can be explained by the striking differences in secondary metabolites of the two growth phases. The principle compound which renders the juvenile phase internodes unpalatable is papyriferic acid, a triterpene which is a demonstrated feeding deterrent to snowshoe hares and which is present in juvenile internodes at concentrations 25 times greater than those in mature internodes.  相似文献   
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Introduction

Platelet counts exceeding 1.000 × 103/μl are usually considered secondary to another cause, particularly to chronic myeloproliferative disease (CMPD). Reactive thrombocytosis due to iron deficiency rarely exceeds platelet counts of 700 × 103/μl.

Case presentation

Here we report the case of a young woman presenting with clinical signs of severe anemia. Laboratory findings confirmed an iron-deficiency anemia associated with severe thrombocytosis of 1703 × 103/μl. Macroscopic gastrointestinal and genitourinary tract bleeding was excluded. The excessive elevation of platelets, slightly elevated lactate dehydrogenase and slightly elevated leukocytes along with the absence of other inflammation parameters raised the suspicion of an underlying hematological disease. However, bone marrow evaluation could not prove the suspected diagnosis of a CMPD, especially essential thrombocythemia (ET). In the further clinical course the platelet count returned to normal after raising the hemoglobin to a level close to normal range with erythrocyte transfusion, and normalization of serum iron and decline of erythropoietin. Finally, following small bowel biopsy, despite the absence of typical clinical signs, celiac disease was diagnosed. After discharge from hospital the patient was commenced on a gluten-free diet and her hemoglobin almost completely normalized in the further follow-up period.

Conclusion

This case illustrates the rare constellation of an extreme thrombocytosis most likely secondary to iron deficiency due to celiac disease. This represents, to the best of the authors' knowledge, the highest reported platelet count coincident with iron deficiency. A potential mechanism for the association of iron-deficiency anemia and thrombocytosis is discussed. Even in the presence of 'atypically' high platelets one should consider the possibility of reactive thrombocytosis. Extreme thrombocytosis could emerge in the case of iron deficiency secondary to celiac disease.
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In the hyphae of Penicillium cyclopium the in vitro measurable activities of 3 enzymes of alkaloid biosynthesis are induced endogenously during  相似文献   
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Summary Five anti-gastrin releasing peptide (GRP) sera have been characterized against GRP, bombesin and related polypeptides spotted on cellulose acetate discs. Antibodies reacting with the C-terminal G-14 sequence of bombesin and the 19–27 sequence of GRP, were detected in all sera. Antibodies directed exclsively against the bombesin unrelated 1–17 sequence of GRP were found only in one serum (R-6902). With parallel immunohistochemical tests only the C-terminal immunoreactivity was detected in endocrine-paracrine cells of the chicken proventriculus, while both immunoreactivities were present in nerve fibres and a few nerve cell bodies of the mammalian gut. The distribution of GRP- and bombesin-like immunoreactive nerves in the gastric mucosa of both pyloric and oxyntic type the submucosal and myenteric plexus along the whole gastrointestinal wall and at sphincter regions is detailed.  相似文献   
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Voigt A  Jakob M  Klösgen RB  Gutensohn M 《FEBS letters》2005,579(6):1343-1349
The receptor components of the chloroplast protein import machinery, Toc34 and Toc159, are both encoded by small gene families in Arabidopsis thaliana. Recent results suggest that each member of these families preferentially interacts with different groups of precursor proteins. Here we address the question, whether multiple homologous Toc receptors are unique to Arabidopsis or whether they are a general phenomenon in plants. Indeed, in spinach we could identify at least two Toc34 proteins with different substrate specificities as demonstrated by competition and antibody inhibition experiments. In addition, an analysis of the available genomic data revealed the presence of at least two Toc34 homologs in six other plant species.  相似文献   
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