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651.

Background

Fanconi anaemia (FA) is a rare genetic disorder associated with bone marrow failure (BMF), congenital anomalies and cancer susceptibility. Stem cell transplantation (SCT) offers a potential cure for BMF or leukaemia, but incurs substantial risks. Little is known about factors influencing SCT decision making.

Objective

The study objective was to explore factors influencing patients' with FA and family members' decision making about SCT.

Design

Using a mixed‐methods exploratory design, we surveyed US and Canadian patients with FA and family members who were offered SCT.

Main variables studied

Closed‐ended survey items measured respondents' beliefs about the necessity, risks and concerns regarding SCT; multivariable logistic regression was used to examine the association between these factors and the decision to undergo SCT. Open‐ended survey items measured respondents' perceptions of factors important to the SCT decision; qualitative analysis was used to identify emergent themes.

Results

The decision to undergo SCT was significantly associated with greater perceived necessity (OR = 2.81, = 0.004) and lower concern about harms of SCT (OR = 0.31, = 0.03). Qualitative analysis revealed a perceived lack of choice among respondents regarding the use of SCT, which was related to physician influence and respondent concerns about patients' quality of life.

Conclusions

Overall, study results emphasize the importance of the delicate interplay between provider recommendation of a medical procedure and patient/parental perceptions and decision making. Findings can help providers understand the need to acknowledge family members' perceptions of SCT decision making and offer a comprehensive discussion of the necessity, risks, benefits and potential outcomes.  相似文献   
652.
BACKGROUND: Allergen challenge in allergic rhinitis patients leads to local eosinophilia and Th2-type cytokine expression. Natural exposure to grass pollen is additionally characterized by epithelial mast-cell infiltration. We hypothesized that perennial allergic rhinitis is also associated with T-cell and eosinophil infiltration of the nasal mucosa, local Th2-type cytokine expression, and increased numbers of nasal epithelial mast cells. METHODS: Nasal biopsies from perennial allergic rhinitis patients and controls were analysed by immunocytochemistry for different cell populations and in situ hybridization for cytokine mRNA-expressing cells. RESULTS: Perennial allergic rhinitis was associated with increased numbers of submucosal CD3+ T cells (P=0.05), EG2+ activated eosinophils (P=0.01), and CD68+ macrophages (P=0.01) compared to controls. Epithelial, but not submucosal, tryptase-positive mast cells were also elevated in rhinitics compared to controls (P=0.01). The numbers of cells expressing interleukin (IL)-5 were higher (P=0.01) and the numbers of cells expressing IL-2 were lower (P=0.04) in rhinitic patients than controls. There were no significant differences for either IL-4 or interferon-gamma between the groups. CONCLUSIONS: Perennial allergic rhinitis is characterized by mast-cell migration into the epithelium; submucosal infiltration by T cells, eosinophils, and macrophages; and an imbalance in local T-cell cytokine production in favour of enhanced IL-5 and reduced IL-2 expression.  相似文献   
653.
用实验性胃溃疡模型研究了PG6E的抗溃疡作用,结果表明PG6E有抗胃酸分泌作用,而对胃肠运动无明显影响;PG6E在剂量为10~80μg·kg-1时,对无水乙醇型、盐酸型、消炎痛型、慢性醋酸型和幽门结扎型胃溃疡有明显保护作用,并能显著减少幽门结扎大鼠的胃液体积、胃酸分泌、胃蛋白酶活性和DNA含量。小鼠poPG6E30~60μg·kg-1,3d后粘膜氨基己糖含量显著增加。研究结果提示PG6E能抑制对胃粘膜的攻击性因素,增加保护性因素的作用,可望成为一种新型抗胃溃疡药。  相似文献   
654.
Hanson  SR; Slichter  SJ 《Blood》1985,66(5):1105-1109
We have studied 16 normal subjects and 27 patients with stable, untreated thrombocytopenia secondary to bone marrow failure and platelet counts ranging from 12,000 to 70,000/microL. Autologous platelets were labeled with 51Cr for measurement of mean platelet life span in the normal subjects and in 20 patients. Labeled donor cells were used in the remaining subjects. Platelet survival, as determined with both autologous and homologous platelets, correlated directly with platelet count in the thrombocytopenic patients. Platelet life span was only modestly reduced in patients having counts in the range of 50,000 to 100,000/microL (7.0 +/- 1.5 days v 9.6 +/- 0.6; P less than .01) but was markedly reduced when the count fell below 50,000/microL (5.1 +/- 1.9 days, P less than .001). The recovery of donor platelets in severely thrombocytopenic recipients (60% +/- 15%) was equivalent to control values (66% +/- 8%; P greater than .2). The recovery of autologous platelets was normal when the platelet count exceeded 50,000/microL (74% +/- 15%) but was reduced in patients with lower counts (50% +/- 22%; P less than .01). All patient and normal data were well correlated by a model predicting a maximum platelet life span of 10 1/2 days and a fixed requirement for 7,100 platelets per microliter of blood per day, or about 18% of the normal rate of platelet turnover, which averaged 41,200 platelets per microliter per day. We conclude that although relatively few platelets are used to support vascular integrity, this requirement is reflected by a reduced platelet life span in marrow hypoplasia and may contribute to the shortening of platelet survival observed in other thrombocytopenias.  相似文献   
655.
Iron oxide/biochar (Fe2O3/biochar) was prepared by green synthesis via a microwave to evaluate ultrasound-assisted adsorption capacity of Nonsteroidal Anti-inflammatory Drugs (NSAIDs) (salicylic acid, naproxen, and ketoprofen) from the water. Several techniques of characterization, including, Fourier transform infrared spectrometry, scanning electron microscopy, EDS analysis, N2 adsorption–desorption, X-ray diffraction, and Raman spectrometry were applied. The adsorption of NSAIDs onto Fe2O3/biochar was performed using an ultrasonic bath. The effects of batch adsorption under various experimental parameters such as contact time (0–120 min), initial concentration (10–500 mg L−1) and pH (2–12) were tested. The obtained Fe2O3/biochar specific surface area, mesopore volume/micropore volume, and pores size were equal to 786 m2 g−1, 0.409 cm3 g−1, and 1.534 cm3 g−1, respectively. The pseudo-second-order model could describe better all NSAID adsorptions onto Fe2O3/biochar. The Langmuir model agreed well with the NSAID adsorptions and the maximum adsorption capacities reached 683 mg g−1, 533 mg g−1 and 444 mg g−1 for salicylic acid, naproxen, and ketoprofen, respectively. Fe2O3/biochar can be used as an excellent adsorbent for the treatment of NSAIDs in water.

Here, we have developed a simple and green microwave synthesis of iron oxide/biochar for the removal of new emergent pharmaceutical pollutants.  相似文献   
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