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991.
992.
ABSTRACT Because maternal-child populations have traditionally been a major practice target for public and community health nursing (P/CHN), understanding the health effects of life transition experiences for women and their children is key to the advancement of P/CHN practice and research. To date there are no integrated conceptual models available that examine transition and its health effects in women, and ultimately their children, to single or multiple transitions. In order to help women and those with dependent children transition successfully, strong transition frameworks for nursing are needed. The purpose of this paper is to describe a conceptual model, Health Effects of Life Transition for Women and Children. Major components include the transition experience (developmental, situational, health illness), transition assets/risks (personal, environmental), cognitive-behavioral health indicators of transition (perception of situation, personal efficacy, change readiness, engagement, help-seeking, health behaviors, services use), transition adaptive outcomes of health (health status, intensity of need for nursing care) and competence (transition specific skill acquisition, health management, resourcefulness) and long-term preventive health outcomes ( risk reduction, disability prevention, cost savings, mastery, injury prevention ). The authors propose that cognitive-behavioral health indicators are foundational to a successful transition experience, are why some people have better transition outcomes than others, and when influenced by P/CHN intervention lead to improved long-term outcomes.  相似文献   
993.
Background: Cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA), as used for infant heart surgery, carry a risk of ischemic neurologic injury. Volatile anesthetics have neuroprotective properties against both global and focal ischemia at normothermia. The authors examined the hemodynamic and neuroprotective effects of desflurane in a piglet CPB-DHCA model.

Methods: Twenty piglets aged 5-10 days received a desflurane- (6-9% expired) or fentanyl-based anesthetic before and during CPB (before and after DHCA). DHCA lasted 90 min at 19[degrees]C brain. Cardiovascular variables (heart rate, arterial pressure, blood gases, glucose, brain temperature) were monitored. On postoperative day 2, neurologic and histologic outcomes were determined.

Results: Cardiovascular variables before, during, and after CPB were physiologically similar between groups. The desflurane group had better neurologic performance (P = 0.023) and greater postoperative weight gain (P = 0.04) than the fentanyl group. In neocortex, the desflurane group had less tissue damage (P = 0.0015) and fewer dead neurons (P = 0.0015) than the fentanyl group. Hippocampal tissue damage was less in the desflurane group (P = 0.05), but overall, neuronal cell counts in the CA1 sector of the right hippocampus were similar to those in the fentanyl group.  相似文献   

994.
BACKGROUND AND PURPOSE: Intensity modulated radiotherapy (IMRT) allows the delivery of higher and more homogeneous radiation dose to head and neck tumours. This study aims to determine the safety of dose-escalated chemo-IMRT for larynx preservation in locally advanced head and neck cancer. METHODS: Patients with T2-4, N1-3, M0 squamous cell carcinoma of the larynx or hypopharynx were treated with a simultaneous-boost IMRT. Two radiation dose levels (DL) were tested: In DL 1, 63 Gy/28F was delivered to primary tumour and involved nodes and 51.8 Gy/28F to elective nodes. In DL 2, the doses were 67.2 Gy/28F and 56 Gy/28F, respectively, representing a 9% dose escalation for the primary. All patients received 2 cycles of neoadjuvant cisplatin and 5-fluorouracil, and concomitant cisplatin. Acute (NCICTCv.2.0) and late toxicity (RTOG and modified LENTSOM) were collected. RESULTS: Thirty patients were entered, 15 in each dose level. All patients completed the treatment schedule. In DL 1, the incidences of acute G3 toxicities were 27% (pain), 20% (radiation dermatitis), 0% (xerostomia) and 67% required gastrostomy tubes. For DL 2 the corresponding incidences were 40%, 20%, 7%, and 87%. G3 dysphagia and pain persisted longer in DL 2. With regard to mucositis, a prolonged healing time for DL 2 was found, with prevalence of G2 of 58% in week 10. No acute grade 4 toxicity was observed. At 6 months, 1 patient in DL 2 had G3 late toxicity (dysphagia). No dose limiting toxicity was found. Complete response rates were 80% in DL 1, and 87% in DL 2. CONCLUSION: Moderately accelerated chemo-IMRT is safe and feasible with good compliance and acceptable acute toxicity. Dose escalation was possible without a significant difference in acute toxicity. Longer follow-up is required to determine the incidence of late radiation toxicities, and tumour control rates.  相似文献   
995.
Recently, we developed sensitive and quantitative methods for analysis of the biomarkers of tobacco smoke exposure nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in human toenails. In this study, we further evaluated the newly developed toenail biomarkers by investigating their relationship to demographic factors, reported exposure, plasma nicotine, cotinine, and trans-3'-hydroxycotinine, and urinary NNAL. Toenails of 105 smokers, mean age 38.9 years (range, 19-68), were analyzed. Fifty-five (53.4%) were male, with approximately equal numbers of Whites and African-Americans. The average number of cigarettes smoked per day was 18 (range, 5-50). There was no effect of age or gender on the toenail biomarkers. Toenail NNAL was higher in White than in African-American participants (P = 0.019). Toenail nicotine and toenail cotinine correlated significantly with cigarettes smoked per day (r = 0.24; P = 0.015 and r = 0.26; P = 0.009, respectively). Toenail nicotine correlated with plasma nicotine (r = 0.39; P < 0.001); toenail cotinine correlated with plasma cotinine (r = 0.45; P < 0.001) and plasma trans-3'-hydroxycotinine (r = 0.30; P = 0.008); and toenail NNAL correlated with urine NNAL (r = 0.53; P = 0.005). The results of this study provide essential validation data for the use of toenail biomarkers in investigations of the role of chronic tobacco smoke exposure in human cancer.  相似文献   
996.
PURPOSE: To better direct targeted therapies to the patients with tumors that express the target, there is an urgent need for blood-based assays that provide expression information on a consistent basis in real time with minimal patient discomfort. We aimed to use immunomagnetic-capture technology to isolate and analyze circulating tumor cells (CTC) from small volumes of peripheral blood of patients with advanced prostate cancer. EXPERIMENTAL DESIGN: Blood was collected from 63 patients with metastatic prostate cancer. CTCs were isolated by the Cell Search system, which uses antibodies to epithelial cell adhesion marker and immunomagnetic capture. CTCs were defined as nucleated cells positive for cytokeratins and negative for CD45. Captured cells were analyzed by immunofluorescence, Papanicolau staining, and fluorescence in situ hybridization. RESULTS: Most patients (65%) had 5 or more CTCs per 7.5 mL blood sample. Cell counts were consistent between laboratories (c = 0.99) and did not change significantly over 72 or 96 h of storage before processing (c = 0.99). Their identity as prostate cancer cells was confirmed by conventional cytologic analysis. Molecular profiling, including analysis of epidermal growth factor receptor (EGFR) expression, chromosome ploidy, and androgen receptor (AR) gene amplification, was possible for all prostate cancer patients with >or=5 CTCs. CONCLUSIONS: The analysis of cancer-related alterations at the DNA and protein level from CTCs is feasible in a hospital-based clinical laboratory. The alterations observed in EGFR and AR suggest that the methodology may have a role in clinical decision making.  相似文献   
997.
PURPOSE: To test the hypothesis that common sequence variants of cell cycle control genes may affect lung cancer predisposition. EXPERIMENTAL DESIGN: We explored lung cancer risk associations of 11 polymorphisms in seven cell cycle genes in a large case-control study including 1,518 Caucasian lung cancer patients and 1,518 controls. RESULTS: When individuals with variant-containing genotypes were compared with homozygous wild-type carriers, a significantly increased lung cancer risk was identified for polymorphisms in p53 intron 6 [rs1625895; odds ratio (OR), 1.29; 95% confidence interval (95% CI), 1.08-1.55] and in p27 5' untranslated region (UTR; rs34330; OR, 1.27; 95% CI, 1.01-1.60). Compared with homozygous wild-types, the homozygous variant genotypes of STK15 F31I and CCND1 G870A were associated with a significantly altered lung cancer risk with ORs of 0.58 (95% CI, 0.37-0.90) and 1.26 (95% CI, 1.03-1.53), respectively. To assess the cumulative effects of all the investigated polymorphisms on lung carcinogenesis, we conducted a combined analysis and found that compared with low-risk individuals with few adverse alleles, individuals with more adverse alleles had an increased risk in a significant dose-dependent manner (P(trend) = 0.041). This pattern was more evident in ever smokers (P(trend) = 0.037), heavy smokers (P(trend) = 0.020), and older subjects (P(trend) = 0.011). Higher-order gene-gene interactions were evaluated using the classification and regression tree analysis, which indicated that STK15 F31I and p53 intron 6 polymorphisms might be associated with lung carcinogenesis in never/light-smokers and heavy smokers, respectively. CONCLUSIONS: Our results suggest that cell cycle gene polymorphisms and smoking may function collectively to modulate the risk of lung cancer.  相似文献   
998.
BACKGROUND: Reducing the nicotine content of cigarettes to make them non-addictive has been widely discussed as a potential strategy for tobacco regulation. A major concern with nicotine reduction is that smokers will compensate for reduced nicotine by smoking more cigarettes and/or smoking more intensively, thereby increasing their exposure to tobacco smoke toxins. This study examined whether gradual reduction in nicotine exposure increases exposure to tobacco smoke toxins. METHODS: This 10-week longitudinal study of 20 healthy smokers involved smoking their usual brand followed by different types of research cigarettes with progressively lower nicotine content, each smoked for 1 week. Subjects were followed for 4 weeks after returning to smoking their usual brand (or quitting). Smoking behaviors, chemical biomarkers of tobacco smoke exposure, and cardiovascular effect biomarkers were measured. FINDINGS: Intake of nicotine declined progressively as the nicotine content of cigarettes was reduced, with little evidence of compensation. Cigarette consumption and markers of exposure to carbon monoxide and polycyclic aromatic hydrocarbons, as well as cardiovascular biomarkers remained stable, whereas urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol excretion decreased. Twenty-five percent of participants had spontaneously quit smoking 4 weeks after completing the research cigarette taper. IMPLICATIONS: Our findings with reduced nicotine content cigarettes differ from those of commercial low yields for which compensatory smoking for lower nicotine delivery is substantial. Our data suggest that the degree of nicotine dependence of smokers can be lowered without increasing their exposure to tobacco smoke toxins. Gradual reduction of nicotine content of cigarettes seems to be feasible and should be further evaluated as a national tobacco regulatory strategy.  相似文献   
999.
PURPOSE: Eleven patients with progressive advanced malignancy after administration of a cancer vaccine received a fully human anti-CTLA-4 monoclonal antibody (ipilimumab). The primary end point was to determine drug toxicity. Tumor response, tumor-specific CD8+ T-cell immune responses, and modulation of CD4+ CD25+ FoxP3+ regulatory T-cell (Treg) numbers were secondary end points. EXPERIMENTAL DESIGN: Three patients with colon cancer, four with non-Hodgkin's lymphoma, and four with prostate cancer were treated. The first dose was given at 3 mg/kg and subsequent doses were administered monthly at 1.5 mg/kg for a total of four cycles. RESULTS: Tumor regression was observed in two patients with lymphoma; one of which obtained a partial response of 14-month duration. Ipilimumab was well tolerated with predominantly grade 1/2 toxicities. One drug-related grade 3 toxicity was observed. One patient died within 30 days of treatment due to progressive colon cancer. No increase in vaccine-specific T-cell responses was observed after therapy. Tregs as detected by expression of CD4+CD25+CD62L+ declined at early time points but rebounded to levels at or above baseline values at the time of the next infusion. CONCLUSIONS: Ipilimumab treatment depressed Treg numbers at early time points in the treatment cycle but was not accompanied by an increase in vaccine-specific CD8+ T-cell responses in these patients previously treated with a variety of investigational anticancer vaccines. A partial response was observed in one patient with follicular lymphoma. A phase I/II trial evaluating ipilimumab in patients with follicular lymphoma is currently ongoing.  相似文献   
1000.
Expression of telomerase is one of the hallmarks of tumor cells and has been used as a diagnostic biomarker and a therapeutic target in cancer. Novel findings have shown that telomerase activation in normal human epithelial cells may affect expression of several cancer-related genes, such as growth-related genes and c-myc gene, suggesting a possible role of telomerase in tumor initiation. Therefore, we hypothesized that individuals who are sensitive to mutagen challenge in terms of induced telomerase activity might have increased cancer risk. We tested this hypothesis in a bladder cancer case-control study (51 cases and 51 matched controls) by measuring baseline and gamma-radiation-induced telomerase activities in peripheral blood lymphocytes. We found a significantly higher gamma-radiation-induced telomerase activity in bladder cancer cases compared with the controls (1.34 versus 1.23; P = 0.044). A similar finding was also observed using the normalized telomerase activity (ratio of gamma-radiation induced versus baseline; 1.49 versus 1.19; P < 0.001). In further categorizing the telomerase activity using 75% of the normalized value in the controls as a cutoff point, we found a significantly increased risk for bladder cancer associated with higher induced telomerase activity (adjusted odds ratio, 3.62; 95% confidence interval, 1.38-9.51). In quartile analysis, a dose-response association was noted between the induced telomerase activity and increased bladder cancer risk (P(trend) = 0.005). Our findings provide the first evidence linking the mutagen-induced telomerase activity in peripheral blood lymphocytes to the risk of bladder cancer, which warrants further investigation in large-sized studies and other cancer types.  相似文献   
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