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51.
Background
Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey.Methods
Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices). Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire.Results
5,209 individuals responded with identical rates in both groups (62.1%). Practice, patient age, sex and Townsend score (a postcode based deprivation measure) were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived).Conclusion
This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire. 相似文献52.
Vengerovskiĭ AI Ogorodova LM Perevozchikova TV 《Eksperimental'naia i klinicheskaia farmakologiia》2004,67(4):50-53
The experiments on rats with a model toxic hepatitis induced by tetrachloromethane showed that hepatoprotectors containing phospholipids (eplir and essentiale) introduced in combination with prednisolone decrease the immunodepressant effect of this glucocorticoid, as manifested by a decrease in the atrophy of thymus and an increase in the amount of blood lymphocytes, the number of splenic blasts, and the functional activity of mononuclear cells in C3b and Fc(gamma) receptors in peritoneal exudate. 相似文献
53.
Understanding diet and energy balance as risk factors for breast, colon,
and other cancers requires information on the contribution of each factor
and of interactions among factors to cancer risk. Rodent models for breast
cancer provide extensive data on effects of dietary fat and calories,
energy balance, body weight gain, and physical activity on tumor
development. Analyses of the combined data from many studies have shown
clearly that quality and quantity of dietary fat and energy balance
contribute independently to increased mammary gland tumorigenesis. These
findings were seen in female rats fed diets high in fat (35-40% of
calories) compared to rats fed control diets, with approximately 10% of
calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46,
215-223). The methods used permit comparison of experimental and
epidemiological data, and they may be useful in extrapolating between
species and developing public health recommendations. In addition to the
contributions of lifetime-diet composition, intake, energy balance, and
physical activity to cancer risk, there are questions about the timing and
duration of alterations in these factors and about the "dose-response"
characteristics of cancer risk to the factors. Endocrine mechanisms may be
significant in mammary gland tumor risk, but experimental and
epidemiological data indicate that cancers at other sites, such as colon
and liver, also are influenced by the factors listed. Other diet and
lifestyle factors that influence energy, or specifically fat, metabolism
may also affect risk for cancers that are promoted by increased intake of
fat and calories. Studies of separate and interactive effects of dietary
fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et
al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using
adjustment of carcinogenesis endpoints for body weight, tumor burden, and
latency, they were found to be related to weight gain within treatment
groups in 2 of 3 experiments.
相似文献
54.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
55.
56.
Daniel TP Fong Mak-Ham Lam Miko LM Lao Chad WN Chan Patrick SH Yung Kwai-Yau Fung Pauline PY Lui Kai-Ming Chan 《Journal of orthopaedic surgery and research》2008,3(1):7
Background
Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running. 相似文献57.
Migraine-associated vertigo 总被引:2,自引:0,他引:2
PA Savundra JD Carroll RA Davies LM Luxon 《Cephalalgia : an international journal of headache》1997,17(4):505-510
A retrospective analysis was performed on consecutive series of 363 patients presenting with vertigo; 32% had migraine. Of the 224 patients with no pathology other than migraine or vestibular dysfunction, migraineurs had a significantly higher prevalence of normal, central, and combined central and peripheral vestibular dysfunction compared to non-migraineurs. The combination of central and peripheral vestibular signs was a feature of migraine with aura. The results support the hypothesis that migraine-associated vertigo is a diagnostic entity. 相似文献
58.
A highly sensitive and specific chemiluminescent enzyme-linked immunosorbent assay for diagnosis of active Trypanosoma cruzi infection 总被引:1,自引:0,他引:1
BACKGROUND: Chagas' disease is transmitted to man either by the bite of insects harboring Trypanosoma cruzi or by the transfusion of blood from infected donors. The conventional serologic testing as presently used in blood banks in South America is unsatisfactory, because of a high number of inconclusive and false-positive results. Other methods such as polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) with recombinant antigens have been proposed, but inherent difficulties have so far precluded their adoption in the large-scale screening required by blood banks. STUDY DESIGN AND METHODS: A highly sensitive and specific chemiluminescent ELISA using a purified trypomastigote glycoconjugate antigen and a complex epimastigote antigen was devised for the diagnosis of active T. cruzi infection. RESULTS: Chemiluminescent ELISA was 100-percent sensitive in the diagnosis of 100 cases of confirmed Chagas' disease. Inconclusive results and false-positive reactions were eliminated in a panel of 115 sera.The specificity of the chemiluminescent ELISA was 100 percent with a purified trypomastigote glycoconjugate antigen and 99.7 percent with a complex epimastigote antigen when applied to 1000 normal human sera and 288 heterologous sera from patients with other infections, including leishmaniasis, and vaccinated individuals. CONCLUSION: The chemiluminescent ELISAs provide a test that is highly sensitive (purified trypomastigote glycoconjugate and complex epimastigote antigens) and specific (purified trypomastigote glycoconjugate antigen) for Chagas' disease diagnosis. It can be used in blood bank screening and to monitor the treatment of patients undergoing chemotherapy. 相似文献
59.
Immunoadsorption for coagulation factor inhibitors 总被引:1,自引:0,他引:1
J Uehlinger ; GR Button ; J McCarthy ; A Forster ; R Watt ; LM Aledort 《Transfusion》1991,31(3):265-269
Inhibitors to coagulation factors are among the most difficult problems in the management of coagulation disorders. Most presently available therapy does not assure hemostasis. An extracorporeal immunoadsorption system, which selectively binds IgG, was used to lower inhibitor levels in eight patients on 10 occasions. In this system, separated plasma is delivered to two staphylococcal protein A-Sepharose columns, which are coupled to an elution monitor. Columns are eluted sequentially and regenerated to maximize IgG removal. Successful removal of the inhibitor was accomplished in all six hemophiliacs on seven occasions, as well as in a patient with acquired von Willebrand disease. All patients whose inhibitors were lowered to less than 10 Bethesda units achieved measurable factor levels when factor concentrate replacement was given. Immunoadsorption facilitates efficient removal of inhibitors, which allows factor replacement therapy. 相似文献
60.
多孔髓芯减压联合干细胞移植治疗股骨头坏死的早期随访结果 总被引:9,自引:0,他引:9
目的:探讨多孔髓芯减压联合自体骨髓干细胞移植治疗股骨头坏死的疗效及临床分析。方法:选择2003-02/2006-12在南京医科大学附属南京第一医院骨关节中心采用多孔髓芯减压联合干细胞移植治疗的股骨头坏死患者22例,共28髋,年龄17~48岁,根据世界骨循环研究学会(ARCO)的国际骨坏死分期标准:Ⅰ期13髋,Ⅱ期11髋,Ⅲ期4髋。长期使用激素史9例,长期酗酒史6例,外伤史5例,原因不明者2例。纳入标准:有髋关节疼痛,功能受限;经髋关节X射线片及MRI检查确诊;ARCO分期Ⅰ~Ⅲ期;患者知情同意并签署知情同意书。排除标准:其他髋关节疾病。自患者髂前上棘处行骨髓穿刺分离与培养骨髓间充质干细胞。取患肢大粗隆下大腿外侧纵向直切口约3.0cm,钝性分离至股骨,在C形臂机引导下自股骨头中心钻入3枚直径4.0mm斯氏针,选位置较好的斯氏针,将直径约8.0mm特制套管在斯氏针的引导下钻至股骨头关节软骨面下1.0~2.0mm,不穿破关节面。将一长注射器针头置入股骨头坏死中心,立即行X射线正侧位摄片,确保针头位于股骨头内,从针头向股骨头内加压注入自体骨髓间充质干细胞悬液1.5~2.0mL。术后12个月随访,每3个月1次,随访时门诊复查,拍正、侧位和蛙式位X射线片,行MRI检查,观察病情变化。使用髋关节Harris评分进行疗效评价,>90分为优,75~90分为良,60~74分为可,<60分评定为差。若Harris评分提高,X射线骨形态变化改善及MRI股骨头坏死区体积变小可认为联合治疗有效。结果:①22例患者均完成随访,进入结果分析。②随访3个月时X射线及MRI检查:2例(2髋)激素引起的Ⅲ期患者股骨头发生进一步变形及塌陷,其余患者在随访期间未出现严重并发症,不良反应及病情恶化。股骨头坏死体积由术前31.07%减小到17.46%。激素组治疗前后股骨头坏死体积差值小于外伤、酗酒组,就本随访资料而言激素组疗效不如外伤及酗酒组。③随访12个月Harris评分:由术前54.3上升到84.6,有较明显提高,其中优7髋(25.0%),良15髋(53.6%),可4髋(14.3%),差2髋(0.07%)。结论:多孔髓芯减压联合干细胞移植是治疗股骨头坏死的一种新手段,尤其适合于年青、ARCO-Ⅰ或Ⅱ期、非激素导致的股骨头坏死治疗。 相似文献