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991.
This article reports on the measurement properties of Caregiver Vigilance, a four-item caregiver self-report of perceived oversight demand for Alzheimer's disease and related disorders family caregiving. The self-report uses data from the Resources for Enhancing Alzheimer's Caregiver Health (REACH) project, a multisite National Institutes of Health (NIH) sponsored study of over 1,200 family caregivers. Results indicate that the items were clearly understood by the racially/ethnically diverse respondents; and, when responses were transformed into a summary scale and analyzed, unidimensionality was evident and internal consistency reliability favorably demonstrated. We suggest using the Caregiver Vigilance Scale in conjunction with traditional burden measures to systematically include the caregiving time associated with protectively watching over care recipients and the daily duration of this responsibility. We also highlight the practical utility of selected items for potential use in the caregiver assessment process.  相似文献   
992.
JOCD has better potential for healing than adult OCD, but several series have shown up to a 50% failure to heal with nonsurgical techniques. JOCD poses a therapeutic dilemma for the pediatric sports specialist because the healing potential is unpredictable at the disease onset. There are no controlled prospective studies on this condition to accurately gauge the effect of different treatments, or even if treatment affects the natural history of JOCD.  相似文献   
993.
Prevention of chemotherapy and radiation toxicity with glutamine   总被引:19,自引:0,他引:19  
GOALS OF THE WORK: Malignancy produces a state of physiologic stress that is characterized by a relative deficiency of glutamine, a condition that is further exacerbated by the effects of cancer treatment. Glutamine deficiency may impact on normal tissue tolerance to antitumor treatment, and may lead to dose reductions and compromised treatment outcome. Providing supplemental glutamine during cancer treatment has the potential to abrogate treatment-related toxicity. We reviewed the available data on the use of glutamine to decrease the incidence and severity of adverse effects due to chemotherapy and/or radiation in cancer patients. METHODS: We performed a search of the MEDLINE database during the time period 1980-2003, and reviewed the English language literature of both human and animal studies pertaining to the use of glutamine in subjects with cancer. We also manually searched the bibliographies of published articles for relevant references. MAIN RESULTS: The available evidence suggests that glutamine supplementation may decrease the incidence and/or severity of chemotherapy-associated mucositis, irinotecan-associated diarrhea, paclitaxel-induced neuropathy, hepatic veno-occlusive disease in the setting of high dose chemotherapy and stem cell transplantation, and the cardiotoxicity that accompanies anthracycline use. Oral glutamine supplementation may enhance the therapeutic index by protecting normal tissues from, and sensitizing tumor cells to chemotherapy and radiation-related injury. CONCLUSIONS: The role of glutamine in the prevention of chemotherapy and radiation-induced toxicity is evolving. Glutamine supplementation is inexpensive and it may reduce the incidence of gastrointestinal, neurologic, and possibly cardiac complications of cancer therapy. Further studies, particularly placebo-controlled phase III trials, are needed to define its role in chemotherapy-induced toxicity.  相似文献   
994.
PURPOSE: The use of partial breast brachytherapy (PBB) after lumpectomy for selected patients with early-stage breast cancer reduces the adjuvant radiotherapy treatment time to <1 week. Despite the advantages of accelerated treatment, maintaining an acceptable cosmetic outcome is important. In a cohort of patients who received low-dose-rate (LDR) or high-dose-rate (HDR) PBB after lumpectomy, the clinical characteristics and treatment parameters were analyzed to identify predictors for an unfavorable cosmetic outcome. METHODS AND MATERIALS: Early-stage breast cancer patients with clear resection margins and 0-3 positive lymph nodes were eligible for PBB. Uniform guidelines for target definition and brachytherapy catheter placement were applied. The HDR PBB dose was 34 Gy in 10 fractions within 5 days, and the LDR dose was 45 Gy given at a rate of 50 cGy/h. The end points included incidence of radiation recall reaction, telangiectasias, and cosmetic-altering fibrosis. RESULTS: Between 1995 and 2000, 44 patients with early-stage breast cancer received PBB without adjuvant external beam radiotherapy after lumpectomy (31 HDR PBB, 13 LDR PBB). After a median follow-up of 42 months (range 18-86), all patients remained locally controlled. The overall rate of good/excellent cosmetic outcome was 79.6% overall and 90% with HDR PBB. Radiation recall reactions occurred in 43% of patients (6 of 14) who received adriamycin. LDR PBB and adriamycin were significant predictors for late unfavorable cosmetic changes in univariate analysis (p = 0.003 and p = 0.005, respectively). CONCLUSION: Although a high rate of local control and good/excellent cosmetic outcome is provided with HDR PBB, the risk of unfavorable cosmetic changes when treated with both LDR PBB and adriamycin is noteworthy. This suggests that HDR PBB is preferred in patients for whom adriamycin is indicated.  相似文献   
995.
Fausch SC  Da Silva DM  Kast WM 《Cancer research》2003,63(13):3478-3482
A causal link between cervical cancer and high-risk human papillomaviruses has been established. The virus infects basal cells of the mucosa, where Langerhans cells are the resident antigen-presenting cells. Langerhans cells and dendritic cells, which are targeted by vaccination, internalize similar amounts of human papillomavirus virus-like particles (VLPs), albeit through different uptake mechanisms. VLP uptake by dendritic cells results in activation and cross-presentation of MHC class I-restricted peptides with costimulation to T cells. Conversely, VLP uptake by Langerhans cells leads to cross-presentation in the absence of costimulation. Efficient VLP cross-presentation by Langerhans cells with costimulation can be achieved by addition of CD40 ligand. The lack of a protective immune response after viral contact with Langerhans cells may explain why some women fail to mount an immune response against the virus or why the immune responses that do develop may allow the virus to persist. Because VLPs are currently being tested as a vaccine against cervical cancer, our data are very topical and have implications for optimal vaccination strategies against this disease.  相似文献   
996.
BACKGROUND: There has been great debate regarding the importance of ductal carcinoma in situ (DCIS) in the breast. Autopsy results that demonstrate a much greater number of these lesions compared with the number of invasive carcinomas, and the numbers of deaths from breast carcinoma each year have been cited as evidence that DCIS rarely leads to invasion and death. These analyses have overlooked the fact that, to sustain a rate of detection each year, there would have to be a reservoir of undetected breast carcinomas growing in the population. The authors developed a simple model that makes this clear. In addition, complex phenomena have been suggested to explain why invasive breast disease may grow more rapidly among very young women and more slowly among the very old. A simple model provides some insight that may simplify the explanation of these observations. METHODS: The simple model of breast carcinoma growth assumes that there are three types of breast carcinoma that begin each year in a cohort of women. It assumes that all breast carcinomas begin as DCIS and take 9 years to go from a single cell to an invasive lesion for the slowest growing lesions, 6 years for intermediate growing DCIS lesions, and 3 years for fast-growing DCIS lesions. Furthermore, once an invasive clone forms, the model assumes that it will double in 60 days for fast-growing lesions, 120 days for intermediate growing lesions, and 180 days for slow-growing lesions. Three new tumors begin to grow in each successive year (one of each type). The model uses simple vectors that are defined by the size of the tumors and the time since tumor initiation, and it assumes that all tumors are detected when they reach 2 cm in greatest dimension. The model can be used to show graphically how many undetected tumors (DCIS as well as invasive carcinomas) there may be in the population to sustain the detection of three invasive tumors each year. RESULTS: Using the assumptions described above, the model showed that, by the time the first slow-growing breast carcinoma reaches 2 cm in greatest dimension, there will be 29 other slow-growing tumors that have not reached that size (9 DCIS and 20 smaller invasive carcinomas), 19 moderately growing tumors (6 DCIS and 13 smaller invasive carcinomas), and 9 fast-growing tumors (3 DCIS and 6 smaller invasive carcinomas). This means that, for every three breast tumors that reach 2 cm, the model predicted that there would be another 57 tumors (39 smaller invasive carcinomas and 18 DCIS) that would be undetected "below the surface". The model showed clearly that faster growing tumors would be expected to predominate among the youngest women, because they are the first to "reach the surface"; and, if the number of newly initiated tumors decreases with age, then there will be more of the slowest growing tumors that are left to reach the surface among the oldest women in the population. CONCLUSIONS: Even if the authors' assumptions are incorrect, their model made it clear that, to diagnose several breast carcinomas per 1000 women each year means that there have to be many more undetected carcinomas in the population to sustain the rate of detection. Although the model did not prove that DCIS may become potentially invasive and lethal, it did demonstrate that, even if all of these in situ lesions become invasive and lethal, many more DCIS lesions would have to be expected in the population than the number of invasive carcinomas detected each year and the number of deaths from breast carcinoma each year. Furthermore, the model provided a simple, purely mechanical illustration that may explain the preponderance of faster growing breast carcinomas among very young women and the preponderance of slower growing tumors among elderly women.  相似文献   
997.
998.
The labour market for nursing: a review of the labour supply literature   总被引:3,自引:0,他引:3  
The need to ensure adequate numbers of motivated health professionals is at the forefront of the modernisation of the UK NHS. The aim of this paper is to assess current understanding of the labour supply behaviour of nurses, and to propose an agenda for further research. In particular, the paper reviews American and British economics literature that focuses on empirical econometric studies based on the classical static labour supply model.American research could be classified into first generation, second generation and recent empirical evidence. Advances in methods mirror those in the general labour economics literature, and include the use of limited dependent variable models and the treatment of sample selection issues. However, there is considerable variation in results, which depends on the methods used, particularly on the effect of wages.Only one study was found that used UK data, although other studies examined the determinants of turnover, quit rates and job satisfaction. The agenda for further empirical research includes the analysis of discontinuities in the labour supply function, the relative importance of pecuniary and non-pecuniary job characteristics, and the application of dynamic and family labour supply models to nursing research. Such research is crucial to the development of evidence-based policies.  相似文献   
999.
Cost-efficiency targets, used to encourage downward pressure on hospital unit costs, have been employed within the UK NHS for many years. There has been considerable speculation that these targets create incentives to reduce beds and increase occupancy rates at the expense of holding spare capacity to accommodate fluctuations in emergency admissions. This research used panel data for the period 1994/1995-1999/2000, supplemented by a series of semi-structured interviews, to explore the strategies Trusts employ to reduce unit costs. No relationship could be found between published targets and changes in unit costs, nor that targets were successful in reducing the dispersion of unit costs over time. Interviews revealed that efficiency gains required of Trusts, usually dictated by the local health economy, often bore no correspondence to the national or regional published targets. Results further indicated that contrary to prior speculation, Trusts divide into two distinct groups, those with high occupancy rates and those with a high proportion of free beds to accommodate emergencies, with Trust characteristics displaying stability over time. A pressing need for future work is the development of measures to encourage efficiency that take account of quality improvement.  相似文献   
1000.
Exposures to farm animals has been associated with certain rare cancers. Simultaneously, using the same methodology and control group, we conducted a six-province incident, population-based study of Hodgkin's disease (HD), multiple myeloma (MM), and soft tissue sarcoma (STS). Farm residence or work was reported by 38% (n = 119) of HD, 45% (n = 178) of MM, 43% (n = 156) of STS cases and 45% (n = 673) of controls. We conducted conditional logistic regression analyses and report odds ratios (OR(adj)) and 95% confidence intervals. After adjustment for covariates, exposure to farm animals had minimal effect on risk. The independent risk factors after adjustment for covariates were a family history of cancer (MM, STS), occupational uranium exposure (HD), professional driving (MM), and personal previous cancer (MM) or shingles (HD, MM).  相似文献   
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