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51.
52.
Jack X Yu Anieta M Sieuwerts Yi Zhang John WM Martens Marcel Smid Jan GM Klijn Yixin Wang John A Foekens 《BMC cancer》2007,7(1):182
Background
Published prognostic gene signatures in breast cancer have few genes in common. Here we provide a rationale for this observation by studying the prognostic power and the underlying biological pathways of different gene signatures. 相似文献53.
WM Bisset P Stapleford S Long A Chamberlain B Sokel PJ Milla 《Archives of disease in childhood》1992,67(1):109-114
In children with severe failure of intestinal function, intravenous nutrition is at present the only treatment able to maintain adequate nutrition for prolonged periods of time. Over the last five years we have discharged 10 patients home on parenteral nutrition for a total of 25 patient years and here the outcome of these children is presented. Of the 10 patients, one has discontinued home parenteral nutrition (HPN), seven patients remain well, one patient has recently moved to the USA, and one patient has died after major abdominal surgery. All children had either normal or an accelerated rate of growth on HPN and developmentally all have progressed well. All the children over 5 years attend normal schools. The major complication of treatment was line sepsis with an overall rate of one episode in 476 days and a total of nine central lines (five patients) have required replacement giving an average line life of 680 days. For those children unfortunate enough to suffer from severe intestinal failure, HPN is preferable to prolonged hospital treatment and offers the chance of a good quality of life with prolonged survival. 相似文献
54.
Clemens M. F. Dirven Joep Tuerlings Willemina M. Molenaar K. Gwan Go David N. Louis 《Journal of neuro-oncology》1995,24(3):251-258
Summary The familial occurrence of gliomas, in the absence of well-defined neurological tumor syndromes such as the neurofibromatoses, is uncommon. We present a family of ten children in which the four eldest suffered from gliomas. Three of these siblings had histologically verified glioblastoma multiforme, and one patient also had an intestinal non-Hodgkin's lymphoma, but there were no stigmata or family history of a neurological tumor syndrome. Cytogenetic studies of the proband revealed a normal karyotype. Molecular genetic analysis of the proband's glioblastoma revealed two mutations in the p53 tumor suppressor gene, but these were not present in the germline DNA, mutations were not detected in the MTS1 gene in the tumors or in the germline DNA. These findings suggest that a genetic factor may be responsible for the clustering of glial tumors in this family, but it is unlikely that the genetic alteration is mutation of the p53 gene. The data are discussed in light of the literature on familial brain tumors. 相似文献
55.
The effect of Cis-platin on the glomerular filtration rate and effective renal plasma flow was determined using a radioisotope clearance technique in young (3 wk old) and adult (more than 12 wk old) rats. Cis-platin was administered intravenously in dosages ranging from 2.5 to 10 mg/kg body weight, either as a single dose or fractionated over 5 consecutive days. Following either dose regimen, identical total doses of Cis-platin caused less severe nephrotoxicity in young rats than in adult ones. In adult rats fractionated dosage significantly reduced nephrotoxicity. This was not observed in young rats. The difference in nephrotoxicity between young and adult rats was due to the renal handling of Cis-platin. After a single dose of 5 and 7.5 mg/kg body weight, platinum concentrations were measured in urine and renal tissue. During the first 2 days after Cis-platin administration, up to 60% of the amount of platinum injected was excreted in the urine of both age groups. There was a marked difference, however, in renal platinum concentration between the two groups. In young rats renal platinum concentration was only 63 and 49% of that in adult rats after 5 and 7.5 mg/kg body weight, respectively. We believe that this is due to the comparatively larger renal mass in relation to body weight in the young animals. Relatively more renal tissue provides at least partial protection against nephrotoxic drugs in these young rats. 相似文献
56.
J H Meijers D Tibboel A W van der Kamp I C Van Haperen-Heuts P Klück J C Molenaar 《Pediatric research》1987,21(5):466-470
Based on experimental studies in mutant mouse strains, an imbalance between the rate of migration of neural crest cells and the rate of differentiation of the mesenchyme of the distal gut has been proposed as an etiological factor in Hirschsprung's disease. We studied the influence of the stage of differentiation of embryonal chick gut on the migration of neural crest cells in an in vivo culture system: the chorioallantoic membrane. Neural crest cells in cultured gut were demonstrated with antibodies directed against the HNK-1 epitope. Enteric neurons were demonstrated with neurofilament immunoreactivity. By culturing isolated gut segments of E4 embryos, we obtained aneuronal (neurofilament-negative) embryonal chick gut up to 25 days of development. In cocultures of aneuronal gut and the neural anlage (neural tube and neural crest) neural crest cell colonization was observed, even in advanced stages of differentiation. The significance of the results is discussed in terms of the etiology of Hirschsprung's disease. 相似文献
57.
Leenders AG van den Maagdenberg AM Lopes da Silva FH Sheng ZH Molenaar PC Ghijsen WE 《The European journal of neuroscience》2002,15(1):13-18
Neurotransmitter release is triggered by Ca2+-influx through multiple sub-types of high voltage-activated Ca2+-channels. Tottering mice have a mutation in the alpha1A pore-forming subunit of P- and Q-type Ca2+-channels, two prominent sub-types that regulate transmitter release from central nerve terminals. Immunoblotting analysis of purified forebrain terminals from tottering mice revealed an 85% reduction in the protein expression level of the mutated alpha1A subunit compared to expression of the alpha1A subunit in wild-type terminals. In contrast, the expression of the alpha1B subunit of the N-type Ca2+-channels was unchanged. Release of the amino acids glutamate and GABA and of the neuropeptide cholecystokinin (CCK) induced by a short (100 ms) depolarization pulse was unchanged in the terminals of tottering mice. Studies using specific blockers of Ca2+-channels however, revealed a reduced contribution of P- and Q-type Ca2+-channels to glutamate and cholecystokinin release, whereas a greater reliance on N-type Ca2+-channels for release of these transmitters was observed. In contrast, the contribution of the P-, Q- and N-type Ca2+-channels to the release of GABA was not altered in tottering mice. These results indicate that the expression of the alpha1A subunit was decreased in terminals from tottering mice, and that a decreased contribution of P- and Q-type Ca2+-channels to the release of glutamate and cholecystokinin was functionally compensated by an increased contribution of N-type Ca2+-channels. 相似文献
58.
Proliferation and Apoptosis in Long-term Surviving Low Grade Gliomas in Relation to Radiotherapy 总被引:11,自引:0,他引:11
Identification of patients with a low grade glioma with a long-term recurrence-free survival is of clinical value as radiotherapy can be postponed until recurrence. The recurring glioma may increase in malignancy compared to the original tumor, which is possibly related to radiotherapy. We studied proliferation by counting mitotic figures and by MIB-1 labeling, apoptosis by TUNEL and expression of proteins related to cell cycle regulation by immunohistochemical analysis of p53, p21, bcl-2 and bax expression in 48 low grade gliomas. Astrocytomas (A, n = 14) and oligodendrogliomas (O, n = 4) with a recurrence-free survival of more than 9 years after surgery had a significantly lower p53 index compared to A (n = 18) and O (n = 12) with a histopathologically documented recurrence. Additionally, the recurrence-free A had a higher p21 index. No significant differences were observed in MIB-LI, TUNEL-LI, bcl-2 and bax expression. Initially low grade gliomas and their corresponding recurrences were compared (n = 30). In the gliomas without radiotherapy (n = 15), no differences in mitotic rate, TUNEL-LI, p53, p21, bcl-2 and bax expression were found between primary tumors and their recurrences. Only MIB-LI was higher in the recurrent tumors. In the gliomas with radiotherapy (n = 15) no differences were detected in these parameters between the original tumor and the recurrent tumor except for a higher number of mitoses in the recurrent tumors. We conclude that low grade gliomas with a long-term recurrence-free survival were characterized by a low p53 protein expression and, in the case of A, a higher p21 index. We found no evidence that radiotherapy is involved in changes of proliferation, apoptosis or expression of proteins related to cell cycle regulation in recurring gliomas. 相似文献
59.
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