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991.
金虹 《营养学报》1996,18(3):300-304
本实验采用AIN-76 ̄(TM)缺铜纯饲料,分别给断奶一周的小鼠喂饲缺铜纯饲料6、7和10周,结果观察到小鼠经过7周喂养后肝Cu水平下降;喂养10周后出现肝细胞色素C氧化酶(CCO)和血清铜蓝蛋白(Cp)活性下降,而肝Cu水平回升,缺铜对小鼠静止的腹腔巨噬细胞产生的肿瘤坏死因子-α(TNF-α)和白细胞介素6(IL-6)活性没有改变。而喂饲3周龄刚断奶的Balb/C雄性小鼠6周后,小鼠呈现严重的缺铜状态,表现为胸腺萎缩、肝脏肿大以及血清Cp活性降低,肝Cu水平、CCO和Cu、Zn-SOD活性明显下降等,并且由缺铜小鼠激活的腹腔巨噬细胞产生的TNF-α、IL-1和IL-6水平明显低于正常组小鼠。  相似文献   
992.

Background

Use of evidence in health policymaking plays an important role, especially in resource-constrained settings where informed decisions on resource allocation are paramount. Several knowledge translation (KT) models have been developed, but few have been applied to health policymaking in low income countries. If KT models are expected to explain evidence uptake and implementation, or lack of it, they must be contextualized and take into account the specificity of low income countries for example, the strong influence of donors. The main objective of this research is to elaborate a Middle Range Theory (MRT) of KT in Uganda that can also serve as a reference for other low- and middle income countries.

Methods

This two-step study employed qualitative approaches to examine the principal barriers and facilitating factors to KT. Step 1 involved a literature review and identification of common themes. The results informed the development of the initial MRT, which details the facilitating factors and barriers to KT at the different stages of research and policy development. In Step 2, these were further refined through key informant interviews with policymakers and researchers in Uganda. Deductive content and thematic analysis was carried out to assess the degree of convergence with the elements of the initial MRT and to identify other emerging issues.

Results

Review of the literature revealed that the most common emerging facilitating factors could be grouped under institutional strengthening for KT, research characteristics, dissemination, partnerships and political context. The analysis of interviews, however, showed that policymakers and researchers ranked institutional strengthening for KT, research characteristics and partnerships as the most important. New factors emphasized by respondents were the use of mainstreamed structures within MoH to coordinate and disseminate research, the separation of roles between researchers and policymakers, and the role of the community and civil society in KT.

Conclusions

This study refined an initial MRT on KT in policymaking in the health sector in Uganda that was based on a literature review. It provides a framework that can be used in empirical research of the process of KT on specific policy issues.  相似文献   
993.
Kim  HS; Lee  BM 《Carcinogenesis》1997,18(4):771-776
The antigenotoxic and chemopreventive effect of Aloe barbadensis Miller (polysaccharide fraction) on benzo[a]pyrene (B[a]P)-DNA adducts was investigated in vitro and in vivo. Aloe showed a time-course and dose- dependent inhibition of [3H]B[a]P-DNA adduct formation in primary rat hepatocytes (1x10(6) cells/ml) treated with [3H]B[a]P (4 nmol/ml). At concentrations of 0.4-250 microg/ml aloe, the binding of [3H]B[a]P metabolites to rat hepatocyte DNA was inhibited by 9.1-47.9%. Also, in rat hepatocytes cultured for 3-48 h with aloe (250 microg/ml) and [3H]B[a]P (4 nmol/ml), [3H]B[a]P-DNA adducts were significantly reduced by 36% compared with [3H]B[a]P alone. Aloe also inhibited cellular uptake of [3H]B[a]P in a dose-dependent manner at a concentration of 0.4-250 microg/ml by 6.3-34.1%. After a single oral administration of B[a]P to male ICR mice (10 mg/mouse), benzo[a]pyrene diol epoxide I (BPDE-I)-DNA adduct formation and persistence for 16 days following daily treatment with aloe (50 mg/mouse) were quantitated by enzyme- linked immunosorbent assay using monoclonal antibody 8E11. In this animal model, BPDE-I-DNA adduct formation was significantly inhibited in various organs (liver, kidney, forestomach and lung) (P < 0.001). When mice were pretreated with aloe for 16 days before B[a]P treatment, inhibition of BPDE-I-DNA adduct formation and persistence was enhanced. Glutathione S-transferase activity was slightly increased in the liver but cytochrome P450 content was not affected by aloe. These results suggest that the inhibitory effect of aloe on BPDE-I-DNA adduct formation might have a chemopreventive effect by inhibition of B[a]P absorption.   相似文献   
994.

Purpose

The purpose of the study was to assess the feasibility of quantifying long-term trends in breast tumor DNA copy number variation (CNV) profiles.

Methods

We evaluated CNV profiles in formalin-fixed paraffin-embedded (FFPE) tumor specimens from 30 randomly selected Kaiser Permanente Northern California health plan women members diagnosed with breast cancer from 1950 to 2010. Assays were conducted for five cases per decade who had available tumor blocks and pathology reports.

Results

As compared to the tumors from the 1970s to 2000s, the older tumors dating back to the 1950s and 1960s were much more likely to (1) fail quality control, and (2) have fewer CNV events (average 23 and 31 vs. 58 to 69), fewer CNV genes (average 5.1 and 3.7k vs. 8.1 to 10.3k), shorter CNV length (average 2,440 and 3,300k vs. 5,740 to 9,280k), fewer high frequency Del genes (37 and 25% vs. 54 to 76%), and fewer high frequency high_Amp genes (20% vs. 56 to 73%). On average, assay interpretation took an extra 60 min/specimen for cases from the 1960s versus 20 min/specimen for the most recent tumors.

Conclusions

Assays conducted in the mid-2010s for CNVs may be feasible for FFPE tumor specimens dating back to the 1980s, but less feasible for older specimens.
  相似文献   
995.
共焦显微镜鉴别诊断真菌性角膜炎的实验研究   总被引:6,自引:2,他引:6  
目的研究利用眼科用共焦显微镜鉴别诊断不同真菌性角膜炎的可行性。方法18只新西兰白兔均分为3组,右眼分别接种白色念珠菌、烟曲霉菌和腐皮镰刀菌。接种时,去除角膜中央区5mm直径的上皮,滴新鲜培养的1×107个细胞/ml的白色念珠菌悬浮液,或涂上新鲜培养的烟曲霉菌或腐皮镰刀菌孢子,盖上软性接触镜,行睑裂缝合。在角膜感染后的第5,10和15天时,行共焦显微镜检查、真菌涂片检查和病理切片检查。结果感染早期(1~5天)炎症反应明显,中期(5~10天)炎症逐渐减轻,10~15天角膜形成疤痕而自愈。烟曲霉菌和腐皮镰刀菌的病程较迁延,反应较白色念珠菌重。共焦显微镜下,感染的白色念珠菌早期主要呈现芽孢状,成高亮度结构,以后发展成具有大量分支的树枝状结构,再发展成链状结构。感染10天后未见任何真菌结构。烟曲霉菌的菌丝在早期则呈较白色念珠菌菌丝粗但分支相对较少的明亮的树枝状结构。中期以后其分支减少并变长,它在角膜组织中保留的时间较白色念珠菌长。在感染早期,腐皮镰刀菌则表现为蚯蚓状结构,以后发展为分支很少的粗短树枝状结构,其分支在3种真菌中最少但直径最粗。真菌涂片和组织学检查的结果与共焦显微镜检查相符。结论共焦显微镜检查对真菌性角膜炎的鉴别诊断有重要的参考价值。  相似文献   
996.
This article reports on the relations between depression and stages of change for smoking cessation. A convenience sample of 205 psychiatric outpatients (68% female, mean age 41) completed measures of depression Primary Care Evaluation of Mental Disorders [PRIME-MD] and Beck Depression Inventory-II [BDI-II]), all transtheoretical model constructs related to smoking (stages and processes of change, pros and cons of smoking, and situational temptations), and thoughts about abstinence. As hypothesized, patients who had never smoked showed substantially lower rates of currently diagnosed major depressive disorder (MDD) than those who had ever smoked. Patients in early stages of change did not show more MDD or depressive symptoms but, as hypothesized, showed more negative thoughts about abstinence. Findings are consistent with the documented association between smoking and depression and suggest the appropriateness of building smoking cessation interventions based on the transtheoretical model of change for use with psychiatric populations.  相似文献   
997.
There is strong evidence indicating that inflammatory bowel disease (IBD) is increasing among black and minority ethnic (BME) communities. Despite this rise in prevalence, there is a paucity of research relating to ethnicity and IBD outside the USA. Furthermore, the symptoms of IBD are reported to start during childhood or adolescence in 20–25% of people with the condition. It is therefore important that young people's experiences of diagnosis, treatment and living with IBD are fully understood to ensure effective services and information provision. The study reported on in this paper was commissioned by a UK charity (Crohn's and Colitis UK) with the aim of increasing understanding of the specific issues and service needs of young people with IBD from BME communities. Empirical research entailed in‐depth semi‐structured interviews with 20 young people from BME groups accessed through gastroenterology departments at three collaborating NHS hospitals in England serving ethnically diverse populations. Interviews were carried out from June to December 2010 and sought to capture young people's views with IBD. A thematic analysis of their experiences identified many commonalities with other young people with IBD, such as the problematic route to formal diagnosis and the impact of IBD on education. The young people also experienced tensions between effective self‐management strategies and cultural norms and practices relating to food. Moreover, the ability of parents to provide support was hampered for some young people by the absence of culturally competent services that were responsive to the families’ communication needs. The findings highlight the need for more culturally appropriate information concerning IBD, and improved responsiveness to young people with IBD within primary care and the education system, as well as culturally competent messaging relating to the specific nature of the condition among the wider South Asian and black communities.  相似文献   
998.
McKENNA K., COLLIER J., HEWITT M. & BLAKE H. (2010) European Journal of Cancer Care 19 , 621–630 Parental involvement in paediatric cancer treatment decisions This study investigated parents' information needs and involvement in decision‐making processes affecting the care of children diagnosed with cancer. Interviews and questionnaires were used to assess parental satisfaction in 50 mothers and 16 fathers responsible for 58 children in an English Paediatric Oncology Unit. Parents reported that doctors contributed almost twice as much to the decision‐making process as they did, but parental satisfaction was positively correlated with the amount of information provided when giving informed consent. Satisfaction about their involvement in this process relied heavily upon the level of support received from others. Parents consenting to their child's involvement in non‐randomised trials perceived themselves to be under greater pressure from others during the decision‐making process while those whose children were further along the treatment trajectory were more uncertain about decisions previously made. Findings indicate that the accessibility, support, information and degree of control afforded to parents by healthcare professionals impacts upon their satisfaction with both the decision‐making process and their confidence in the decisions thus made. Information and support tailored to parents' specific needs may therefore enhance satisfaction with clinical decision making and reassure parents about decisions made in the long‐term interest of their child's health.  相似文献   
999.

BACKGROUND.

Testing for human papillomavirus (HPV) is used in the triage of women with a cervical cytology of atypical squamous cells of undetermined significance (ASCUS). A fluorescent in situ hybridization assay was developed for the detection of HPV using the catalyzed receptor deposition technique (HPV‐CARD). In this study, the utility of this assay was tested for the detection of HPV in liquid‐based cervical cytology specimens.

METHODS.

A total of 195 liquid‐based cytology specimens were analyzed using the HPV‐CARD assay. The results from the assay were compared with HPV polymerase chain reaction (PCR) and typing results. The number of HPV‐infected cells and the staining pattern was correlated with the cytology classification.

RESULTS.

A 91% concordance between HPV‐CARD and PCR was observed for the detection of high‐risk HPV viruses. A 78% concordance was observed for specimens that were negative for HPV. In ASCUS, low‐grade squamous intraepithelial lesion (LSIL), and high‐grade squamous intraepithelial lesion (HSIL) categories, the average number of HPV‐positive cells per slide was 19 cells, 127 cells, and 450 cells, respectively. The number of cells with a punctate staining, suggestive of HPV integration, was 21% in ASCUS, 34% in LSIL, and 46% in HSIL specimens.

CONCLUSIONS.

The results of the current study indicate positive correlations between the severity of the disease and the increased overall quantity of HPV‐positive epithelial cells in cervical cytology specimens and accumulation of cells with punctate staining suggestive of integrated HPV. In summary, the developed HPV‐CARD assay was found to provide novel information regarding the proportion and staining pattern of HPV‐infected epithelial cells in different cytologic categories of cervical specimens. Cancer (Cancer Cytopathol) 2007. © 2007 American Cancer Society.  相似文献   
1000.
Background/objectivesThe certification process to register patients as sight impaired or severely sight impaired is undertaken by consultant ophthalmologists, in the UK. We sought to assess the agreement between optometrists and a consensus panel, in identifying patient eligibility for certification, relative to the agreement between ophthalmologists and the consensus panel.MethodsThe consensus panel (4 consultant ophthalmologists and 3 optometrists with a formal accreditation in low vision), 30 consultant ophthalmologists and 99 low vision optometrists reviewed 40 randomly selected abridged cases. The eligibility outcomes from the ophthalmologists and the optometrists were compared with the consensus panel outcomes.ResultsFor ophthalmologists and optometrists, the median (IQR) number of cases in which there was agreement with the consensus panel was 33.0 (31.0, 33.0) and 36.0 (34.0, 36.5), respectively. In severely sight impaired cases, the probabilities of agreeing on eligibility for certification were 76.0% (95% CIs 71.4%, 80.1%) for ophthalmologists and 61.8% (59.0%, 64.6%) for optometrists. In sight impaired cases, the corresponding values were 51.6% (46.7%, 56.4%) for ophthalmologists and 72.2% (69.8%, 74.5%) for optometrists. In cases of bilateral atrophic age-related macular degeneration (AMD), both groups were more likely to agree with the consensus panel and the differences between optometrists and ophthalmologists were less marked.ConclusionsOptometrists demonstrated a comparable agreement relative to ophthalmologists, with the consensus panel on the eligibility of randomly selected, abridged cases for certification. The findings support the clinical decision-making ability of low vision optometrists in the certification of patients with vision impairment and provide evidence in support of policy change to allow low vision optometrists to certify individuals with atrophic AMD.Subject terms: Health occupations, Health services, Public health  相似文献   
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