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81.
FL Porter  CM Wolf  J Gold  D Lotsoff  JP Miller 《Pediatrics》1997,100(4):626-632
BACKGROUND: Despite an increased awareness among clinicians regarding pain and pain management for infants undergoing surgery, pain associated with procedures performed outside the operating room may not be adequately managed. PURPOSE: To examine the beliefs and self-described behavior of physicians and nurses regarding the management of procedural pain in newborn infants. METHODS: A survey was distributed to 467 clinicians (nurses and physicians) working in 11 level II and 4 level III nurseries in a large metropolitan area. Respondents were asked to rate the painfulness of 12 common bedside nursery procedures and how often pharmacologic and nonpharmacologic (comfort) measures are currently used and should be used for those procedures. Demographic data were also collected. RESULTS: Surveys were completed by 374 clinicians (80% response rate). Physicians and nurses believe infants feel as much pain as adults and that 9 of the 12 listed procedures are moderately to very painful. Neither pharmacologic nor comfort measures are believed to be used frequently, even for the most painful procedures. Physicians and nurses believe both pharmacologic and comfort measures should be used more frequently, but nurses believe comfort measures should be used more frequently than do physicians. Beliefs about infant pain and procedural pain were related to pain management preferences. Physicians' but not nurses' ratings were associated with significant personal pain. CONCLUSIONS: Despite their beliefs that infants experience significant procedure-related pain, clinicians believe pain management for infants remains below optimal levels. Barriers to more consistent and effective pain management need to be identified and surmounted.  相似文献   
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An Australian study of functional status after childbirth   总被引:1,自引:0,他引:1  
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85.
A treatment regimen that takes advantage of the induction of intracellular porphyrins such as protoporphyrin IX (PPIX) by exposure to exogenous 5-amino-laevulinic acid (ALA) followed by localized exposure to visible light represents a promising new approach to photodynamic therapy (PDT). Acting upon the suggestion that the effectiveness of ALA-dependent PDT may depend upon the state of cellular differentiation, we investigated the effect of terminal differentiation upon ALA-induced synthesis of and the subsequent phototoxicity attributable to PPIX in primary mouse keratinocytes. Induction of keratinocyte differentiation augmented intracellular PPIX accumulation in cells treated with ALA. These elevated PPIX levels resulted in an enhanced lethal photodynamic sensitization of differentiated cells. The differentiation-dependent increase in cellular PPIX levels resulted from several factors including: (a) increased ALA uptake, (b) enhanced PPIX production and (c) decreased PPIX export into the culture media. Simultaneously, steady-state levels of coproporphyrinogen oxidase mRNA increased but aminolaevulinic acid dehydratase mRNA levels remained unchanged. From experiments using 12-o-tetradecanoylphorbol-13-acetate, transforming growth factor beta 1 and calcimycin we demonstrated that the increase in PPIX concentration in terminally differentiating keratinocytes is calcium- and differentiation specific. Stimulation of the haem synthetic capacity is seen in primary keratinocytes, but not in PAM 212 cells that fail to undergo differentiation. Interestingly, increased PPIX formation and elevated coproporphyrinogen oxidase mRNA levels are not limited to differentiating keratinocytes; these were also elevated in the C2C12 myoblast and the PC12 adrenal cell lines upon induction of differentiation. Overall, the therapeutic implications of these results are that the effectiveness of ALA-dependent PDT depends on the differentiation status of the cell and that this may enable selective targeting of several tissue types.  相似文献   
86.
Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
87.
We have developed a non-invasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers. In this study, we used the rat colon carcinogenesis model to determine if changes in fecal protein kinase C (PKC) expression have predictive value in monitoring the neoplastic process. Weanling rats were injected with saline or azoxymethane (AOM) and 36 weeks later fecal samples and mucosa were collected, poly A+ RNA isolated, and quantitative RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and zeta mRNA levels were altered by the presence of a tumor, with tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII expression as compared with animals without tumors. In addition, AOM-injection increased mucosal PKC betaII mRNA expression compared with saline controls. No effect of tumor incidence on mucosal PKC betaII expression was observed. In contrast, fecal PKC zeta expression was 2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus saline. Since tumor incidence exerts a reciprocal effect on fecal PKC betaII and zeta mRNA expression, data were also expressed as the ratio between PKC betaII and zeta. The isozyme ratio was strongly related to tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25, animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that the expression of fecal PKC betaII and zeta may serve as a noninvasive marker for development of colon tumors. A sensitive technique for the detection of colon cancer is of importance since early diagnosis can substantially reduce mortality.   相似文献   
88.
Spindles are one of the most important short-lasting waveforms in sleep EEG. They are the hallmarks of the so-called Stage 2 sleep. Visual spindle scoring is a tedious workload, since there are often a thousand spindles in one all-night recording of some 8 hr. Automated methods for spindle detection typically use some form of fixed spindle amplitude threshold, which is poor with respect to inter-subject variability. In this work a spindle detection system allowing spindle detection without an amplitude threshold was developed. This system can be used for automatic decision making of whether or not a sleep spindle is present in the EEG at a certain point of time. An Autoassociative Multilayer Perceptron (A-MLP) network was employed for the decision making. A novel training procedure was developed to remove inconsistencies from the training data, which was found to improve the system performance significantly.  相似文献   
89.
Perspectives on colorectal cancer screening: a focus group study   总被引:3,自引:0,他引:3  
Objective To assess attitudes and acceptability of Ontario consumers and doctors towards colorectal screening with faecal occult blood testing (FOBT) and colonoscopy. Design, setting and participants Focus groups with gender‐specific samples of the population, high‐risk gastroenterology patients and family doctors. Method Semi‐structured interview guides used by facilitator to lead groups through knowledge of risk factors and prevention of colorectal cancer, the screening modalities, requirements for implementing screening programmes, barriers to screening and preferences towards screening. Main findings There were low levels of knowledge about colorectal cancer and its prevention in the general population. FOBT was an acceptable screening modality, but considerable education about its use and benefits would be necessary to implement a screening programme. Colonoscopy was not perceived to be a good choice for a primary screen in the general population. The high‐risk group supported use of FOBT in the general population and emphasized the need for education. The doctors were more reluctant about screening, requesting clear guidelines. They also identified the time and resources that would be required if a screening programme were initiated. Conclusion While colorectal screening is acceptable in this sample, information and decision aids are required to enable consumers and providers to make effective decisions. Implementation of colorectal screening programmes requires substantial educational efforts for both consumers and doctors.  相似文献   
90.
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