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91.
The purpose of this article is to analyse and discuss preschool teachers' views regarding competence within their profession in the context of home and preschool collaboration. The question addressed is as follows: In what situations do preschool teachers perceive that their competence becomes visible for parents? The results, based on interviews with 30 preschool teachers, show that preschool teachers work consciously to draw attention to specific competencies related to children's learning and development and the preschool curriculum. The ability to establish dialogue with parents and gain their trust is seen as particularly important for establishing and maintaining collaboration between preschool and the home. Furthermore, the participants recognise that parents seek their competence in daily matters concerning the child's well-being. The competencies that preschool teachers emphasise and those they believe parents ask for do not, therefore, always coincide. The results of this study can contribute to a better understanding of the prerequisites for preschool–home collaboration.  相似文献   
92.
93.
Robertsonian translocations between the acrocentric autosomes are the most common type of constitutional chromosome rearrangement in humans. However, Robertsonian translocations are very rarely acquired in cancer cells. We report a patient with prolymphocytic leukemia and an acquired Robertsonian translocation in the leukemic cells. The translocation was between chromosomes #13 and #15; t(13;15)(q11;p12). Two other cases of malignancy with an acquired Robertsonian translocation have been found, one being of the t(13;15) type, which accounts for only 1% of constitutional Robertsonian translocations. We propose, therefore, that although Robertsonian translocations are occasionally observed in cancer cells, they are very rarely acquired.  相似文献   
94.
Chromosome studies were performed on an adrenocortical carcinoma extending into the kidney. The following karyotype was present in all metaphases: 46,XX,t(4;11)(q35;p13). Two metaphases with an additional del(1)(q23) were found. The results are briefly discussed in relation to specific karyotypic changes in cancer, in general, and to those of adrenocortical tumors, in particular.  相似文献   
95.
Three cases with chromosome changes involving bands 7p14 or 7p15 and 11p15 are described: one was a Japanese female with an acute myelomonocytic leukemia, the second was a white female with a 10-year history of paroxysmal nocturnal hemoglobinuria who developed a myelodysplastic syndrome, and the third was a patient with Ph-negative atypical chronic myelogenous leukemia with trisomy 8 and a chromosome change involving bands 7p14 and 11p15. These cases possibly indicate that the t(7;11)(p14 or p15;p15) change may characterize a subset of human nonlymphocytic neoplasia.  相似文献   
96.
Tryptophan degradation along the kynurenine pathway is of central importance for the immune function. Toll‐like receptors (TLRs), representing the first line of immune defence against pathogens, are expressed in various cell types. The most abundant expression is found on monocytes, macrophages and dendritic cells. The aim of this study was to investigate whether stimulation with different TLR ligands induces the kynurenine pathway in human peripheral monocytes. Cell supernatants were analysed using a liquid chromatography/mass spectrometry to measure kynurenine, kynurenic acid (KYNA), quinolinic acid (QUIN) and tryptophan. Stimulation of TLR‐2, TLR‐3, TLR‐4, TLR‐7/8 and TLR‐9 was found to induce the production of kynurenine, but only stimulation of TLR‐3 increased levels of further downstream metabolites, such as KYNA and QUIN. Stimulation of TLR‐1, TLR‐5 and TLR‐6 did not induce the kynurenine pathway. Taken together, this study provides novel evidence demonstrating that TLR activation induces a pattern of downstream tryptophan degradation along the kynurenine pathway in monocytes. The results of this study may implicate that TLRs can be used as new drug targets for the regulation of aberrant tryptophan metabolism along this pathway, a potential therapeutic strategy that may be of importance in several disorders.  相似文献   
97.
A case of acute nonlymphocytic leukemia with a new translocation, t(2;7)(p13;q36), as the sole karyotypic abnormality is reported. The patient's leukemia evolved from a cytogenetically normal myelodysplastic syndrome of 4 years' duration. Following treatment the patient entered complete remission with loss of the cytogenetically abnormal clone. Subsequent bone marrow analyses showed recurrence of the myelodysplastic syndrome with a normal karyotype. Although both chromosomes 2 and 7 are known to be involved in nonrandom karyotypic changes in human cancer and leukemia, t(2;7)(p13;q36) has not been reported previously.  相似文献   
98.
We studied cytogenetically three distinct lipomas from a patient with multiple subcutaneous lipomas in the left shoulder area. A breakpoint at 12q14 was involved in structural rearrangements in the three lipomas resulting in two different reciprocal translocations, i.e., t(3;12)(q28;q14) in two and a t(1;12)(q34.2;q14) in the third. These results confirm the consistency of involvement of the breakpoint at 12q14 in lipomas and give support to the hypothesis that multiple lipomas evolve from different stem cells.  相似文献   
99.
Cytogenetic studies were performed on human malignant melanoma cells from eight metastatic lesions. Five tumors displayed near-triploid and three near-diploid chromosome numbers. Chromosomes #1,#6,#7, followed by #2 and #9, were found to be most frequently involved in structural aberrations. Aberrations involving chromosome #1, with deletions or translocations of 1p, involving region 1p12-1p22 in seven of eight breakpoints of the p arm were observed. Seven of nine breakpoints of 6q were located at region 6q15-6q21. Most of the breakpoints on chromosome #7 occurred near the centromeric region. All tumors had additional chromosome material involving 1q, chromosome #7 (7q in two tumors), and in five tumors an increased dose of chromosome #6 (6p in one tumor). The nonrandom breakpoints of these and other chromosomes involved diverse bands, including loci of oncogenes and fragile sites. The observation of nonrandom chromosomal changes in advanced malignant melanoma suggests that genes important in the progression of melanoma are located on chromosomes #1,#6, and #7.  相似文献   
100.
A cytogenetic study of a leiomyosarcoma of the small bowel revealed numerical and structural chromosome changes. Several of these changes, in particular the loss of one chromosome #14, #15, #18, and #22, and del(1)(p12p13) have been reported previously in an unrelated leiomyosarcoma of the small bowel. We suggest that these or part of these findings could be characteristic of leiomyosarcoma of the small bowel.  相似文献   
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