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Dr J. O. Lopes D. V. Pereira L. A. Streher A. A. Fenalte S. H. Alves J. P. Benevenga 《Mycopathologia》1995,130(2):89-92
A case of cutaneous zygomycosis caused byAbsidia coryabifera in a leukemic patient submitted to chemotherapy is reported. The lesion was located on the little finger of the right hand and probably resulted from a latent osteomyelitis. It progressed to form extensive necrotic area. No systemic infection was detected and the lesion did not appear to be associated with any trauma. 相似文献
14.
40 pelvic preparations of rabbits (oryctolagus cuniculus) were bilaterally studied by dissection under the stereomicroscope and angiography. The arterial pattern of the pelvis, i.e. origin and branching of the umbilical, urogenital and internal pudendal arteries (visceral branches), is described. The main characteristics observed are as follows: (1) The umbilical artery is permeable in adults and gives origin to the cranial vesical artery and a caudal branch that irrigates the pelvic urogenital organs and, eventually, the rectum, with six patterns of branching in both sexes. (2) Usually, the urogenital artery is the continuation of the visceral branch of the internal iliac artery. In 1 animal, unilaterally, it arises from the median sacral artery. In 12 animals (6 bilaterally and 6 unilaterally) the urogenital artery is absent. When present, it forms two branches, a cranial and a caudal one, that irrigate of the urogenital organs in both sexes. (3) The internal pudendal artery is the direct continuation of the internal iliac artery and gives to rise to some visceral branches that irrigate the penis, bulbourethral gland and rectum (with six patterns of branching) in males, and the vagina, clitoris and rectum (with three patterns of branching) in females. 相似文献
15.
Kazu Kurosawa W.David Ollis Brian T. Redman Ian O. Sutherland Herbert M. Alves Otto R. Gottlieb 《Phytochemistry》1978,17(8):1423-1426
The absolute configurations of isoflavans and isoflavanquinones isolated from Cyclolobium, Dalbergia and Machaerium species were established by comparison of their ORD curves with that of (3S)-5,7,3′,4′-tetra-methoxyisoflavan and (3S)-7,4′-dimethoxyisoflavan-2′,5′-quinone, respectively. The assignments were checked by the ozonolysis of the isoflavan (?)-duartin to (R)-paraconic acid and the oxidation of isoflavans to isoflavanquinones. The PMR spectra of the dihydropyran ring of the isoflavans are discussed in terms of the preferred conformation of this ring. 相似文献
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As in the case of the succinate and sarcosine dehydrogenases of liver mitochondria, the flavin prosthetic group of the bacterial sarcosine dehydrogenase can be released from the enzyme by proteolytic digestion with trypsin and chymotrypsin. The flavin, isolated in the dinucleotide form and covalently bound to a peptide fragment, is converted to the mononucleotide and purified by sequential chromatography on Sephadex G-25, DEAE-Sephadex A-25, followed by preparative paper chromatography and high voltage electrophoresis.The absorption maxima of the purified flavin at pH 7 are found at 268, 350, and 447 nm, with 268:447 nm and 350:447 nm ratios of 3.08 and 0.79, respectively. The fluorescence excitation and emission maxima, 450 and 530 nm, respectively, are similar to those of flavin mononucleotide. The fluorescence of the flavin-peptide is maximal at pH 3.0–3.1.Amino acid analysis of the flavin-peptide (riboflavin form) gave the following molar ratios of amino acids to flavin: Lys(1), Asp(2), Thr(1), Ser(1), Glu(1), Gly(1), and Ala(1). Aspartic acid was the N-terminal amino acid. Upon more extensive hydrolysis, histidine was obtained in 71–84% yields. Employing aminopeptidase M, the partial sequence of amino acids in the flavin-peptide was determined to be as follows: Flavin -Asp-Lys-Ser-Glu-Gly-His-(Asp,Ala,Thr)-Evidence is presented that the isoalloxazine ring is linked covalently via its 8 α-methyl group to N-3 of histidine. 相似文献
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G. Ragone R. Caizzi R. Moschetti P. Barsanti V. De Pinto C Caggese 《Molecular genetics and genomics : MGG》1999,261(4-5):690-697
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Polymorphism in the promoter region of the mannose-binding lectin gene among human T-cell lymphotropic virus infected subjects 总被引:1,自引:0,他引:1
Alves AE Hermes RB Tamegão-Lopes B Machado LF Azevedo VN Ishak MO Ishak R Lemos JA Vallinoto AC 《Memórias do Instituto Oswaldo Cruz》2007,102(8):991-994
The present study investigated the frequency of the mutations at positions -550 and -221 of the mannose-binding lectin (MBL) gene in a sample of 75 human T-cell lymphotropic virus (HTLV) infected patients and 96 HTLV seronegative controls, in order to evaluate the occurrence of a possible association between the polymorphism and HTLV infection. A sequence specific primer-polymerase chain reaction was used for discrimination of the polymorphism. The analysis of allele frequencies at position -550 did not show any significant differences between HTLV infected group and controls, but there was a significant difference at position -221. The comparative analysis of haplotypes frequencies were not significant, but the genotype frequencies between the two groups, revealed a higher prevalence of genotype LYLX (25.3%), associated with medium and low MBL serum levels among HTLV infected subjects. The odds ratio estimation demonstrated that the presence of genotype LYLX was associated with an increased risk of HTLV infection (p = 0.0096; 1.38 < or = IC95% < or = 7.7605). There was no association between proviral load and the promoter polymorphism, but when promoter and exon 1 mutations were matched, it was possible to identify a significant higher proviral load among HTLV infected individuals carrying haplotypes correlated to low serum levels of MBL. The present study shows that the polymorphism in the promoter region of the MBL gene may be a genetic marker associated with HTLV infection, and emphasizes the need for further studies to determinate if the present polymorphism have any impact on diseases linked to HTLV infection. 相似文献
20.
Isolated rat hearts perfused with Chenoweth-Koelle solution exhibit tachyphylaxis to tyramine. This tachyphylaxis was prevented if tyrosine was included in the perfusion solution. Other amino acids, including glycine, serine, phenylalanine, valine, tryptophan, glutamate, aspartate, arginine, lysine and
-tyrosine, failed to prevent the tyramine-induced tachyphylaxis. Hearts from reserpinized animals showed increased chronotropy after tyramine only when tyrosine was present in the medium. This response could be blocked by
, m-hydroxybenzyl-hydrazine and d,l-propanolol, indicating that it was mediated by the synthesis and release of catecholamines. These experiments suggest that sympathetic nerves in the isolated rat heart exhibit a requirement for tyrosine when catecholamine release is enhanced. 相似文献