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21.
A 32P-postlabelling method is reported for the detection of7-alkylguanines, the major adducts formed by the reaction of1,2-alkylepoxides with DNA. Calf thymus DNA was reacted in vitrowith different epoxides (ethylene oxide through octylene oxide)and digested with micrococcal nuclease and spleen phosphodiesteraseto 3'-nucleotides. The adduct enrichment was carried out byan ion-exchange method and adducts were labelled with [  相似文献   
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Håberg A  Kvistad KA  Unsgård G  Haraldseth O 《Neurosurgery》2004,54(4):902-14; discussion 914-5
OBJECTIVE: This study sought to evaluate the ability of blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to successfully identify functional cortical areas in patients with primary brain tumors, to evaluate the use of the fMRI results in presurgical planning, and to assess the functional outcome of the patients with respect to the functional maps obtained with fMRI. METHODS: The study included 25 consecutive preoperative fMRI sessions in patients with primary brain tumors in or near sensorimotor and/or language cortices. All fMRI paradigms were analyzed and rated according to the degree of success. Several distances between tumor and functional cortex as delineated with BOLD fMRI were measured to assess the topographic relationship between these two structures. Pre- and postoperative neurological statuses were obtained from the patients' journals. RESULTS: Acquisition of BOLD fMRI images was successful in 80% of the cases. The primary cause of unsuccessful fMRI was echo-planar imaging signal voids that were the result of previous craniotomy; the secondary cause was excessive motion. The neurosurgeons used the fMRI results for preoperative planning in 75% of the cases in which fMRI was successful. The risk of postoperative loss of function tested with fMRI was significantly lower when the distance between tumor periphery and BOLD activity was 10 mm or more. CONCLUSION: The majority of patients with primary brain tumors were capable of satisfactorily performing the fMRI paradigms, and the information obtained was used in the preoperative planning. A distance of 10 mm or more between the functional cortex, as delineated with fMRI, and the tumor significantly reduced the risk of postoperative loss of function.  相似文献   
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Alterations in TGF-beta signaling appear to be associated with an altered risk of developing cancer, including breast cancer. We carried out a case-control study on 8 polymorphisms, including 5 in the TGF-beta1 gene (G-800A, C-509T, Leu10-->Pro, Arg25-->Pro and Thr263-->Ile), a polyalanine polymorphism (9A-->6A) in the TGF-betaRI gene and 2 (G-875A and A-364G) in the TGF-betaRII gene, using samples from 2 different populations, Polish familial and Finnish unselected breast cancer cases, together with ethnically and geographically matched controls. Additionally, familial breast cancer cases with respective controls from Sweden and Germany were studied in the Leu10-->Pro polymorphism, making the total number of familial cases 659. Allele, genotype and haplotype analysis on the TGF-beta1 gene as well as an analysis of the combinations of genotypes of the TGF-beta1 and its receptor genes in each individual were performed. Population differences in the allele and genotype distributions were found from 5 of the polymorphisms and 3 common haplotypes from the TGF-beta1 gene between the Finnish and other populations. However, no statistically significant difference between the breast cancer and healthy control groups was found for any of the 8 polymorphisms nor did the haplotype or genotype combination analysis reach statistical significance. Thus, none of the studied polymorphisms from the TGF-beta1 and its receptor genes was found to influence significantly susceptibility to breast cancer. The possible contribution of 6A/6A homozygosity in the TGF-betaRI gene to breast cancer needs to be confirmed in an independent study.  相似文献   
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Nursing diagnosis taxonomy across the Atlantic Ocean: congruence between nurses' charting and the NANDA taxonomy Purpose and aims . The purpose of this study was to analyse expressions or terms used by nurses in Iceland to describe patient problems. The classification of NANDA was used as reference. The research questions were: (a) Does NANDA terminology represent patient problems documented by Icelandic nurses? (b) If so, what kind of nursing diagnoses does it represent? (c) What kind of patient problems are not represented by NANDA terminology? (d) What are the most frequent nursing diagnoses used? Methods. A retrospective chart review was conducted in a 400 bed acute care hospital in Iceland. The sample was defined as nursing diagnosis statements in charts of patients hospitalized in two 6‐month periods in two separate years. The data were analysed according to a predefined grading system based on the PES format or Problem – (A)aetiology – Signs and symptoms. Results. A total of 1217 charts were used for the study, which yielded 2171 nursing diagnoses statements for analysis. Charts with at least one nursing diagnosis documented were 60·1% and the number of diagnoses per patient ranged from 0 to 10, with 65% of charts with three diagnoses or less. The number of diagnoses correlated with patients' length of stay, but not with increased age of the patients. The average number of statements per patient was 3·28. Almost 60% of the diagnoses were according to NANDA terminology, another 20% were stated as procedures, medical diagnoses or risks for complications. The 20 most frequently used nursing diagnoses accounted for 80% of all diagnoses documented. Discrepancy between nurses' documentation on emotional problems and availability of diagnosis in the NANDA taxonomy was evident. Conclusion. It can be concluded that the NANDA taxonomy seems to be culturally relevant for nurses in different cultures.  相似文献   
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Aminolevulinic acid (ALA), ALA methylester (ALA-Me) and ALA hexylester (ALA-Hex) were topically applied for 5 and 20 hr, respectively, on normal skin of mice. The distribution of protoporphyrin IX (PpIX) induced in 7 different tissues by these drugs was determined either by spectrofluorometric measurements with an optical fibre probe or by chemical extraction of PpIX from the tissues. The results from these 2 types of measurements were compared. Both methods showed that ALA and the esters induced similar amounts of PpIX at the skin spot where they were applied and that the esters produced much less PpIX at remote skin spots (i.e., spots outside the location where the drugs were applied) than ALA did, notably after 20 hr application. After 20 hr of drug application ALA produced much more PpIX in liver, intestine and lungs than the esters did. In contrast with the direct fluorescence measurements, the extraction method showed detectable amounts of PpIX in liver, intestine and lung after application of the esters, notably of ALA-Me. The discrepancy is probably related to the fact that the pigmented tissues absorb light and, therefore, the direct fluorescence readings are misleading. Notably in the liver, which contains high concentration of light-absorbing pigments, very weak direct fluorescence was seen. In no case there was any accumulation of PpIX in muscle tissue nor in brain. The esters seem to penetrate less into the circulation than ALA, and PpIX formed by them in the skin is faster cleared than PpIX formed from ALA. This is also true after oral and i.p. administration of the drugs.  相似文献   
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BACKGROUND: Infant cry characteristics reflect the integrity of the central nervous system. Previous studies have shown that preterm infants and infants with neurological conditions have different cry characteristics such as fundamental frequency compared to healthy full-term infants. Cry characteristics of preterm infants after the first year of life have not been studied. AIMS: The aim of this study was to assess the quality of cry in 1 1/2-year-old very-low-birth-weight infants (VLBWI, < or =1500 g at birth). STUDY SUBJECTS AND DESIGN: Study groups included 21 VLBWI and 25 healthy full-term controls. Thirty seconds of pain cry after vaccination was recorded at well-baby clinics. The first cry utterance was acoustically analyzed using Praat software. The quality of cry was compared between the groups. In addition, the association of cry quality to patient characteristics, to developmental outcome, and to findings in brain imaging studies of the VLBWI was studied. RESULTS: The cry response was elicited in 20 of the 21 VLBWI and in 20 out of 25 full-term infants. VLBWI had higher minimum fundamental frequency and fourth formant values. Patient characteristics that were associated with cry quality were 5-min Apgar scores, the occurrence of bronchopulmonary dysplasia, Bayley Psychomotor Index scores at 12 months, and current weight and head circumference. CONCLUSIONS: Differences found between the study groups were not explained primarily by brain pathology or by patient characteristics, so it seems that prematurity has an impact on cry quality still at the age of 1 1/2 years.  相似文献   
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The aim of this study is to investigate how community-living older people interpret the Norwegian version of Older People's Quality of Life (OPQOL) questionnaire. The original OPQOL questionnaire was translated based on guidelines for cross-cultural translation. The Three-Step Test-Interview instrument was adopted to investigate how community-living older people interpreted the questionnaire. Data were collected from 14 participants (72–89 years). The questionnaire was filled in under observation. Semi-structured interviews were then conducted to clarify the observational data and elicit the participants’ experiences and opinions. Lastly, data were analysed using a hermeneutic interpretation approach. Our findings indicate that most of the participants managed to complete the OPQOL questionnaire without problems. The data analysis resulted in four primary themes: relevance & applicability, formulation, consistency & accuracy and subjectivity. The questionnaire covered all aspects related to the participants’ quality of life. However, statements related to religion were found to be irrelevant to their quality of life. Most of the participants thought that religion, philosophy and culture should be separate rather than included in the same statement. The participants missed the option of ‘not applicable’ when the statements were irrelevant to them. The statements are formulated in both positive and negative ways, which was sometimes confusing to them. The participants perceived phases such as “around me” “local,” and “things” as ambiguous, and thus they raised concerns about whether the OPQOL questionnaire could capture consistent data regarding their quality of life. The results of this study pinpoint the issues that community-living older people faced when interpreting and answering the Norwegian version of OPQOL questionnaire. These issues were mostly caused by sociocultural differences. Our work provides an overview of the changes that must be made in the questionnaire in order to address these sociocultural differences while using the OPQOL questionnaire in the Norwegian context.  相似文献   
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