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81.
Ecotoxicology - Variations of temperature and photoperiod throughout different seasons can affect aquatic communities such as biofilms. Biofilms, generally present at the base of trophic chains in...  相似文献   
82.
Anemia and decreased health-related quality of life (HRQL) are common in patients receiving combination therapy of interferon alfa (IFN) and ribavirin (RBV) for chronic hepatitis C virus (HCV) infection. In a randomized, prospective study evaluating the effectiveness of epoetin alfa in maintaining RBV dose, alleviating anemia, and improving HRQL in anemic (Hb < or = 12 g/dL) HCV-infected patients receiving combination therapy, patients receiving epoetin alfa had significant improvements in HRQL compared with placebo. In this study, 185 patients were randomized to 40,000 units of epoetin alfa subcutaneously weekly or placebo for an 8-week double-blind phase (DBP), followed by an 8-week open-label phase during which all patients received epoetin alfa. To further assess the impact of epoetin alfa on HRQL, post hoc analyses were conducted in the same patient population to compare the HRQL of these patients at randomization with norms of other populations, and to determine the critical relationship between hemoglobin (Hb) levels and HRQL. Mean HRQL scores of anemic HCV-infected patients receiving combination therapy at randomization were significantly lower than those of both the general population and patients who had other chronic conditions. Patients receiving epoetin alfa who had the greatest Hb increases from randomization to the end of the DBP also had the largest improvements in HRQL. Hb improvement was an independent predictor of HRQL improvement in these patients. In conclusion, epoetin alfa provided clinically significant HRQL improvement in HCV-infected patients receiving IFN/RBV therapy.  相似文献   
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OBJECTIVES: To determine the effectiveness of pressure bandaging in reducing bleeding and bruising in patients undergoing coronary angiography and to investigate the contribution that pressure bandages make to patient discomfort after angiography.DESIGN: A prospective multicenter, randomized study.SETTING: Three university hospitals in Melbourne, Australia.PATIENTS: One thousand seventy-five patients undergoing coronary angiography were randomized to receive a pressure bandage (N = 556) or no bandage (N = 519) after manual compression of the right femoral artery puncture site.RESULTS: Patients without pressure bandages had a higher incidence of bleeding (P < 0.05) and bled earlier (mean 2.4 hours; SD 3.6 hours) after catheter removal (P < 0.001) than patients with bandages (mean 5.3 hours; SD 3.8 hours). The incidence of bleeding in patients without pressure bandages was 6.7%. The incidence and extent of bruising was the same for both groups. Patients with pressure bandages experienced a higher incidence of back (P < 0.05), groin (P < 0.001), and leg pain (P < 0.001), nausea (P < 0.05), and urinary difficulty (P < 0.01).CONCLUSIONS: In view of the associated increase in patient discomfort and the delay in time of onset of bleeding, pressure bandages should not be used routinely in the management of patients after coronary angiography, especially in the context of early discharge from the hospital.  相似文献   
84.
We reviewed interventions that affect maternal and child undernutrition and nutrition-related outcomes. These interventions included promotion of breastfeeding; strategies to promote complementary feeding, with or without provision of food supplements; micronutrient interventions; general supportive strategies to improve family and community nutrition; and reduction of disease burden (promotion of handwashing and strategies to reduce the burden of malaria in pregnancy). We showed that although strategies for breastfeeding promotion have a large effect on survival, their effect on stunting is small. In populations with sufficient food, education about complementary feeding increased height-for-age Z score by 0.25 (95% CI 0.01-0.49), whereas provision of food supplements (with or without education) in populations with insufficient food increased the height-for-age Z score by 0.41 (0.05-0.76). Management of severe acute malnutrition according to WHO guidelines reduced the case-fatality rate by 55% (risk ratio 0.45, 0.32-0.62), and recent studies suggest that newer commodities, such as ready-to-use therapeutic foods, can be used to manage severe acute malnutrition in community settings. Effective micronutrient interventions for pregnant women included supplementation with iron folate (which increased haemoglobin at term by 12 g/L, 2.93-21.07) and micronutrients (which reduced the risk of low birthweight at term by 16% (relative risk 0.84, 0.74-0.95). Recommended micronutrient interventions for children included strategies for supplementation of vitamin A (in the neonatal period and late infancy), preventive zinc supplements, iron supplements for children in areas where malaria is not endemic, and universal promotion of iodised salt. We used a cohort model to assess the potential effect of these interventions on mothers and children in the 36 countries that have 90% of children with stunted linear growth. The model showed that existing interventions that were designed to improve nutrition and prevent related disease could reduce stunting at 36 months by 36%; mortality between birth and 36 months by about 25%; and disability-adjusted life-years associated with stunting, severe wasting, intrauterine growth restriction, and micronutrient deficiencies by about 25%. To eliminate stunting in the longer term, these interventions should be supplemented by improvements in the underlying determinants of undernutrition, such as poverty, poor education, disease burden, and lack of women's empowerment.  相似文献   
85.
Home‐based primary care (HBPC) is an effective model of noninstitutional long‐term care developed in the Department of Veterans Affairs (VA) to provide ongoing care to homebound persons. Significant rural populations of American Indians have limited access to services designed for frail older adults. Fourteen Veterans Affairs Medical Centers (VAMCs) initiated efforts to expand access to HBPC in concert with local tribes and Indian Health Service (IHS) facilities. This study characterizes the resulting emerging models of HBPC and co‐management. Using an observational design, key respondent telephone interviews (n = 37) were conducted with stakeholders representing the 14 VAMCs to describe these HBPC programs, and HBPC models were evaluated in relation to VAMC organizational culture as revealed on the annual VA All Employee Survey. Twelve VAMCs independently developed HBPC expansion programs for American Indian veterans, and six different program models were implemented. Two models were unique to collaborations between VAMCs and tribes; in these collaborations, the tribes retained primary care responsibilities. VAMC used the other four models for delivery of care in remote rural areas to all veteran populations, American Indians and non‐Indians alike. Strategies to improve access by reducing geographic barriers occur in all models. Comparing mean VAMC organizational culture ratings, as defined in the Competing Values Framework, revealed significant group differences for one of these six models. Findings from this study illustrate the flexibility of the HBPC program and opportunities for co‐management and expansion of healthcare access for American Indians and non‐Indians, particularly in rural areas.  相似文献   
86.
This report describes altered cell foci observed 9-14 days after treatment with 3-methylcholanthrene of mouse-embryo tissue cultures that had previously been infected with wild-type AKR (RNA tumor) virus. The foci consisted of randomly oriented, piled-up, spindle-shaped cells. When heavily stained with Giemsa, the colonies of transformed cells were grossly visible and countable. Under the same experimental conditions, such changes of morphology were not detectable in the uninfected cells treated with 3-methylcholanthrene or in untreated cells infected with virus. The procedure may provide a rapid, quantitative test system for measurement of the oncogenic potential of certain carcinogens. As in similar previous studies in rat and hamster cells, the results suggest that the infectious, but nontransforming, RNA tumor viruses provided nascent oncogenic information, which when activated by 3-methylcholanthrene served as the specific genetic determinants of transformation.  相似文献   
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Background

HER2 fluorescence in-situ hybridization (FISH) is used in breast and gastro-esophageal carcinoma for determining HER2 gene amplification and patients' eligibility for HER2 targeted therapeutics. Traditional manual processing of the FISH slides is labor intensive because of multiple steps that require hands on manipulation of the slides and specifically timed intervals between steps. This highly manual processing also introduces inter-run and inter-operator variability that may affect the quality of the FISH result. Therefore, we sought to incorporate an automated processing instrument into our FISH workflow.

Methods

Twenty-six cases including breast (20) and gastro-esophageal (6) cancer comprising 23 biopsies and three excision specimens were tested for HER2 FISH (Pathvysion, Abbott) using the Thermobrite Elite (TBE) system (Leica). Up to 12 slides can be run simultaneously. All cases were previously tested by the Pathvysion HER2 FISH assay with manual preparation. Twenty cells were counted by two observers for each case; five cases were tested on three separate runs by different operators to evaluate the precision and inter-operator variability.

Results

There was 100% concordance in the scoring between the manual and TBE methods as well as among the five cases that were tested on three runs. Only one case failed due to poor probe hybridization. In total, seven cases were positive for HER2 amplification (HER2:CEP17 ratio > 2.2) and the remaining 19 were negative (HER2:CEP17 ratio < 1.8) utilizing the 2007 ASCO/CAP scoring criteria. Due to the automated denaturation and hybridization, for each run, there was a reduction in labor of 3.5 h which could then be dedicated to other lab functions.

Conclusion

The TBE is a walk away pre- and post-hybridization system that automates FISH slide processing, improves work flow and consistency and saves approximately 3.5 h of technologist time. The instrument has a small footprint thus occupying minimal counter space. TBE processed slides performed exceptionally well in comparison to the manual technique with no disagreement in HER2 amplification status.  相似文献   
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