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1.
Although immune mechanisms can suppress tumour growth, tumours establish potent, overlapping mechanisms that mediate immune evasion. Emerging evidence suggests a link between angiogenesis and the tolerance of tumours to immune mechanisms. Hypoxia, a condition that is known to drive angiogenesis in tumours, results in the release of damage-associated pattern molecules, which can trigger the rejection of tumours by the immune system. Thus, the counter-activation of tolerance mechanisms at the site of tumour hypoxia would be a crucial condition for maintaining the immunological escape of tumours. However, a direct link between tumour hypoxia and tolerance through the recruitment of regulatory cells has not been established. We proposed that tumour hypoxia induces the expression of chemotactic factors that promote tolerance. Here we show that tumour hypoxia promotes the recruitment of regulatory T (T(reg)) cells through induction of expression of the chemokine CC-chemokine ligand 28 (CCL28), which, in turn, promotes tumour tolerance and angiogenesis. Thus, peripheral immune tolerance and angiogenesis programs are closely connected and cooperate to sustain tumour growth.  相似文献   
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Methylation of lysine residues of histones is associated with functionally distinct regions of chromatin, and, therefore, is an important epigenetic mark. Over the past few years, several enzymes that catalyze this covalent modification on different lysine residues of histones have been discovered. Intriguingly, histone lysine methylation has also been shown to be cross-regulated by histone ubiquitination or the enzymes that catalyze this modification. These covalent modifications and their cross-talks play important roles in regulation of gene expression, heterochromatin formation, genome stability, and cancer. Thus, there has been a very rapid progress within past several years towards elucidating the molecular basis of histone lysine methylation and ubiquitination, and their aberrations in human diseases. Here, we discuss these covalent modifications with their cross-regulation and roles in controlling gene expression and stability. Received 24 September 2008; received after revision 21 November 2008; accepted 28 November 2008  相似文献   
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Résumé L'activité nutritive deM. pustulata Thunb. est en général plus intense sur les plantes d'Hibiscus rosasciensis et sur ses fleurs particulier, à la lumière aussi bien que dans l'obscurité. La lumière ne joue donc pas de rôle important dans l'alimentation de cet insecte.

The authors are indepted to Prof.H. S. Chaudhry for providing necessary facilities during the work.  相似文献   
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Summary A diet containing 18–20 mg iron/kg to young weaned rats for 8 weeks altered the metabolism of gamma-aminobutyric acid and glutamate in the central nervous system without affecting blood hemoglobin. Subsequent rehabilitation with 390 mg iron/kg diet for 2 weeks normalized these changes.  相似文献   
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Zusammenfassung Aus den Wurzeln vonArnebia nobilis wurden 4 antibiotisch wirksame Stoffe isoliert. Die Struktur von dreien wurde aufgeklärt.

On deputation from the Chemistry Department, Lucknow University.

To whom enquiries should be made. The isolation of shikonin monoacetate and,-dimethylacrylate fromLithosperm erythrorhizon, I.Morimoto, T.Kishi, S.Ikegana and Y.Hirata, Tetrahedron Lett.4737 (1965), has been brought to our notice since communicating this paper.

Communication No. 1305 from the Central Drug Research Institute.  相似文献   
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Zusammenfassung Die stündliche Pepsinsekretion bei dreissig Vitiligo-kranken und 15 gesunden Personen wurde nach Histaminstimulation gemessen. Bei den Vitiligo-Kranken wurden zwei Drittel der normalen Pepsinsekretion beobachtet.

Thanks are due to Mr.R. K. Soraut for his valuable assistance in this work.  相似文献   
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Zusammenfassung Der Plasma- und der Urin-Askorbinsäurespiegel wurden während der postoperativen Periode nach täglicher Zufuhr von 500 mg Vitamin C bei Patienten kolorimetrisch gemessen. Der schnelle Verbrauch des Vitamins macht einen Askorbinsäurebedarf zur Kollagensynthese am Ort der Wunde wahrscheinlich.  相似文献   
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