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排序方式: 共有1221条查询结果,搜索用时 203 毫秒
81.
Wang JF; Bashir M; Engelsberg BN; Witmer C; Rozmiarek H; Billings PC 《Carcinogenesis》1997,18(2):371-375
Chromium (Cr) is a human carcinogen and a potent DNA damaging agent.
Incubation of DNA with CrCl3 resulted in dose-dependent binding of Cr to
DNA and, at concentrations >20 microM, altered the electrophoretic
mobility of a 100 bp oligonucleotide. We also demonstrate that high
mobility group (HMG) proteins 1 and 2 bind Cr-damaged DNA (Cr-DNA). Protein
binding was lesion density-dependent, with maximal binding to DNA treated
with 100 microM CrCl3. HMG2 binds to Cr-DNA with a calculated Kd of
approximately 10(-9) M. These proteins also bound DNA obtained from
chromate-treated cells. These results suggest that the covalent attachment
of Cr to DNA induces alterations in DNA structure which are recognized by
HMG1 and HMG2. Therefore, these proteins may function as Cr-damaged DNA
recognition proteins in vivo and as a consequence of binding, may play a
role in directing the cellular response to Cr-DNA adduct formation.
相似文献
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83.
The Authors report a case of adrenal pseudocyst surgically treated (complete resection) in a 42 years old symptomatic woman. They discuss the pathological and clinical features of the adrenal cysts and pseudocysts and stress the peculiarity of the case observed. 相似文献
84.
Treatment of allergic bronchopulmonary aspergillosis (ABPA) has remained both problematic as well as controversial. Although the sheet anchor in treatment of ABPA still remains steroids, various workers have tried oral antifungals (fluconazole and itraconazole) with encouraging results. This study evaluates the effect of fluconazole or itraconazole in the treatment of ABPA patients and compares them with the patients who had received palliative therapy other than antifungals. Case records of 44 proven cases of ABPA treated at our referral service hospital during February 1998 to April 2001 were analyzed. In addition to oral and inhaled bronchodilators, 16 patients received fluconazole 150 mg OD and 13 patients itraconazole 200 mg OD for six months. Response to therapy was assessed clinically, radiologically and by spirometry every 3 months. Patients who did not receive antifungals had chronic course characterized by airway obstruction, recurrent pulmonary consolidation and obstructive defect on pulmonary function test (PFT). Patients treated with itraconazole had better control of asthma symptoms, less requirement of reliever inhalers, steroids and lesser exacerbations of asthma during follow-up even after stopping antifungal. Fluconazole group had better control of symptoms but improvement in other parameters was not statistically significant. From this study it was evident that itraconazole improved the symptoms of airway obstruction, pulmonary functions, pulmonary opacities and decreased exacerbations during follow up.Key Words: Allergic bronchopulmonary aspergillosis, Fluconazole, Itraconazole 相似文献
85.
PURPOSE OF REVIEW: This review deals with classification and treatment of some rare nonsquamous cell carcinomas of the head and neck. RECENT FINDINGS: Paranasal sinus tumor classification is under evaluation. Contrary to the past, the recent tendency is to build stage classifications on prognostic factors that mainly reflect limitations for adequate surgery, and not simply on dimensional criteria, which are more frequently used in TNM. Among sinonasal tract tumors new pathologic entities have been described. So far, little is known about their natural history and about the need to use pathologic classification to differentiate treatment. Recent advances in radiotherapeutic techniques, such as intensity-modulated radiotherapy, will probably have an impact on future treatment of paranasal sinus tumors. Several molecular targets (c-kit, HER-2/neu, androgen receptors) have been identified in salivary gland cancer. It is interesting to note that among different histotypes there is a trend toward a consistent expression of specific markers in specific cancers, suggesting a possible implication of them in the disease histogenesis. Not surprisingly these findings prompted clinical research with molecular targeted drugs. SUMMARY: Nonsquamous cell carcinomas of the head and neck are rare neoplasms. A multidisciplinary team treatment plan is needed, in particular for skull base-located tumors. Salivary gland cancer displays several molecular targets that need to be investigated further. 相似文献
86.
TP53, p14ARF,p16INK4a and H-ras gene molecular analysis in intestinal-type adenocarcinoma of the nasal cavity and paranasal sinuses 总被引:2,自引:0,他引:2
Perrone F Oggionni M Birindelli S Suardi S Tabano S Romano R Moiraghi ML Bimbi G Quattrone P Cantu G Pierotti MA Licitra L Pilotti S 《International journal of cancer. Journal international du cancer》2003,105(2):196-203
Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses is an uncommon tumor associated with occupational exposure to dusts of different origin. Few investigations addressed molecular alterations in ITAC mainly focused on TP53, K-ras and H-ras gene mutations. The occurrence of TP53, p14(ARF) and p16(INK4a) deregulation and H-ras mutations was investigated in 21 consecutive and untreated ITACs cases, 17 with known professional exposure. No H-ras mutations were found. In patients with known exposure, cumulative evidence of TP53 or p14(ARF) alterations accounted for 88% and the evidence of p16(INK4a) alterations for 65%, respectively. TP53 mutations were present in 44% of the ITACs, consisted of G:C-->A:T transitions in 86%, and involved the CpG dinucleotides in 50% of the cases. LOH at the locus 17p13 and an uncommon high rate of p53 stabilization were detected in 58% and 59% of the cases, respectively. p14(ARF)and p16(INK4a) promoter methylation accounted for 80% and 67% respectively, and LOH at the locus 9p21 occurred in 45% of the cases. Interestingly, all dust-exposed tumors with p16(INK4a) alterations shared TP53 or p14(ARF) deregulation. The present results show a close association of this occupational tumor with TP53, p14(ARF) and p16(INK4a) gene deregulation. Given the important role that these genes play in cell growth control and apoptosis, the knowledge of ITAC genetic profile may be helpful in selecting more tailored treatments. 相似文献
87.
Marjolein Gysels MA PhD Alison Richardson BN MSc PhD RN PGDip Ed RNT † Irene J. Higginson BMBS FFPHM PhD FRCP ‡ 《Health expectations》2007,10(1):75-91
OBJECTIVES: To assess the effectiveness of the patient-held record (PHR) in cancer care. BACKGROUND: Patients with cancer may receive care from different services resulting in gaps. A PHR could provide continuity and patient involvement in care. SEARCH STRATEGY: Relevant literature was identified through five electronic databases (Medline, Embase, Cinahl, CCTR and CDSR) and hand searches. INCLUSION CRITERIA: Patient-held records in cancer care with the purpose of improving communication and information exchange between and within different levels of care and to promote continuity of care and patients' involvement in their own care. DATA EXTRACTION AND SYNTHESIS: Data extraction recorded characteristics of intervention, type of study and factors that contributed to methodological quality of individual studies. Data were then contrasted by setting, objectives, population, study design, outcome measures and changes in outcome, including knowledge, satisfaction, anxiety and depression. Methodological quality of randomized control trials and non-experimental studies were assessed with separate standard grading scales. MAIN RESULTS AND CONCLUSIONS: Seven randomized control trials and six non-experimental studies were identified. Evaluations of the PHR have reached equivocal findings. Randomized trials found an absence of effect, non-experimental evaluations shed light on the conditions for its successful use. Most patients welcomed introduction of a PHR. Main problems related to its suitability for different patient groups and the lack of agreement between patients and health professionals regarding its function. Further research is required to determine the conditions under which the PHR can realize its potential as a tool to promote continuity of care and patient participation. 相似文献
88.
Developing information literacy: a key to evidence-based nursing 总被引:9,自引:0,他引:9
A. Shorten RN CM BN MSc . C. Wallace RN BA GradDipEd Med P. A. Crookes RN RNT BSc PhD 《International nursing review》2001,48(2):86-92
This report describes the evaluation of a curriculum-integrated programme designed to help students develop an awareness of the nursing literature, the skills to locate and retrieve it, and skills required in its evaluation; in other words'information literacy'. Positive changes in student performance on objective measures of information-literacy skills were revealed as well as a significant increase in the levels of confidence of the student in performing those skills. Students who had undertaken the information-literacy programme ('programme' students) performed better on a range of objective measures of information literacy, as well as reporting higher levels of confidence in these skills, than students who had not participated in the programme ('non-programme' students). Evaluation of this programme provides evidence of the potential usefulness of a curriculum-integrated approach for the development of information-literacy skills within nursing education. With these underlying skills, students will be better equipped to consolidate and extend their key information-literacy skills to include research appreciation and application. These are vital for effective lifelong learning and a prerequisite to evidence-based practice. 相似文献
89.
90.
AMANDA HENDERSON B.Sc PhD KARYN PATERSON B Sc M Ed. LIZ BURMEISTER RN MSc BERNADETTE THOMSON BN M Ed LOUISE YOUNG BN 《Journal of nursing management》2013,21(2):368-376
Background Registered nurses are difficult to recruit and retain. Task shifting, which involves reallocation of delegation, can reduce demand for registered nurses. Effective leadership is needed for successful task shifting. Objective This study explored leadership styles of three surgical nurse unit managers. Staff completed surveys before and after the implementation of task shifting. Task shifting involved the introduction of endorsed enrolled nurses (licensed nurses who must practise under registered nurse supervision) to better utilize registered nurses. Methods Implementation of task shifting occurred over 4 months in a 700-bed tertiary hospital, in southeast Queensland, Australia. A facilitator assisted nurse unit managers during implementation. The impact was assessed by comparison of data before (n = 49) and after (n = 72) task shifting from registered nurses and endorsed enrolled nurses (n = 121) who completed the Ward Organization Features Survey. Results Significant differences in leadership and staff organization subscales across the settings suggest that how change involving task shifting is implemented influences nurses’ opinions of leadership. Conclusion Leadership behaviours of nurse unit managers is a key consideration in managing change such as task shifting. Implications for nursing management Consistent and clear messages from leaders about practice change are viewed positively by nursing staff. In the short term, incremental change possibly results in staff maintaining confidence in leadership. 相似文献