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排序方式: 共有307条查询结果,搜索用时 15 毫秒
41.
Signe Berit Bentsen RN TN MNSc PhD Doris Gundersen PhD Joerg Assmus PhD Biostatistican Heidi Bringsvor RN CCN MSc Astrid Berland RN AN MNSc 《Nursing & health sciences》2013,15(3):292-299
This paper examines the prevalence of multiple symptoms and the relationships between future expectations and multiple symptoms in a cross‐sectional study of 100 patients with chronic obstructive pulmonary disease. A questionnaire was used to examine the patients’ symptoms of breathlessness, anxiety, depression, sleeplessness, fatigue, and pain, and their outlook for the future. All patients reported breathlessness, 64% anxiety, 69% depression, 28% sleeplessness, 72% fatigue, and 45% pain. Those with anxiety reported significant depression (P < 0.001), and those with fatigue reported significant depression (P = 0.004). Patients who reported pain also reported significant sleeplessness (P = 0.022). A negative outlook for the future was reported by 42% of patients who also reported significantly more anxiety, depression, sleeplessness, fatigue, and pain (P ≤ 0.049). Multiple symptoms are common in chronic obstructive pulmonary disease, and patients with a pessimistic view of the future reported more symptoms. Those with multiple symptoms and a negative outlook toward the future may benefit from interventions to help them achieve a more positive outlook for the future, which may relieve symptom burden. 相似文献
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目的 建立一种快速、灵敏的高效液相色谱-串联质谱(HPLC-MS/MS)方法以测定人血浆中对乙酰氨基酚浓度,并应用于两种对乙酰氨基酚制剂的人体药代动力学和生物等效性研究。方法 以替硝唑为内标,200μL血浆样品经5倍于其体积的乙酸乙酯液液萃取,再经Waters XBridge? C18柱等度洗脱分离后导入串联质谱,以正离子多反应监测模式进行定量分析,对乙酰氨基酚和内标的选择性反应离子对分别是m/z 152→110和248→121。方法经验证后应用于19名健康受试者单剂量空腹口服两种对乙酰氨基酚制剂500mg后药代动力学和生物等效性的研究。结果 血浆中对乙酰氨基酚在0.1~8.0 μg·mL-1范围内线性良好(r2 > 0.99),最低检测限为 0.1 μg·mL-1,提取回收率为91.0%~98.7%,日内和日间准确度分别为98.8%~111.3% (精密度:CV ? 9.03%)和94.9%~102.6% (精密度:CV ? 10.68%)。生物等效性试验中,受试制剂与参比制剂的主要药代动力学参数Cmax、AUC0-t和AUC0-∞ 几何均值比的90%置信区间分别为83.50%~105.79%,94.25%~101.54%和93.24%~101.02%,均落在生物等效可接受标准80.00%~125.00%范围内。结论 所建立测定人血浆中对乙酰氨基酚浓度的HPLC-MS/MS法具有快速灵敏、回收率高、选择性好的特点,适用于对乙酰氨基酚片人体药代动力学和生物等效性研究。受试制剂与参比制剂在人体内吸收速度和程度相似,两种制剂生物等效。 相似文献
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An expandable metal stent was inserted to relieve bronchial obstruction following lobectomy for localised squamous carcinoma which had not been relieved by bronchoplasty with a Goretex flap. This resulted in substantial improvement in lung function and exercise tolerance for nine months, following which severe inflammation around the stents required residual pneumonectomy. 相似文献
46.
Identification and characterization of proteinase K-resistant proteins in members of the class Mollicutes 总被引:2,自引:2,他引:0 下载免费PDF全文
G H Butler H Kotani L Kong M Frick S Evancho E J Stanbridge G J McGarrity 《Infection and immunity》1991,59(3):1037-1042
Proteins resistant to proteinase K are rare because of the potency, wide pH optimum, and low peptide bond specificity of this enzyme. Previously, only the prion proteins associated with transmissible spongiform encephalopathies, possibly related proteins in the mollicute Spiroplasma mirum, and proteinase K itself have been reported. We identified a new proteinase K-resistant protein, p40-pr, in two strains of Mycoplasma hyorhinis and in extracts of these organisms. p40-pr's are similar to prion proteins in their resistance to high doses of proteinase K and in the reversal of this resistance by strong denaturing conditions. However, p40-pr's were distinct immunologically, in relative molecular mass, and in their method of extraction. Two immunologically related forms of p40-pr were identified on sodium dodecyl sulfate (SDS) gels and Western immunoblots, a 40-kDa species in boiled samples and a 120-kDa species dissociable by boiling in SDS. Reduction with 2-mercaptoethanol did not affect the mass of p40-pr's or the 120-kDa forms. The development of proteinase K resistance of p40-pr correlated to age-dependent increases in organism protein-lipid ratios. p40-pr-like proteinase K-resistant proteins of 46 to 50 kDa were identified in four of eight additional species of the class Mollicutes but not in S. mirum. However, these mycoplasmal proteins did not react with antibody to the denatured 40-kDa form of M. hyorhinis p40-pr purified by electroelution. The chromatographically purified 46-kDa proteinase K-resistant protein of Mycoplasma orale was an arginine deiminase. 相似文献
47.
Suppression of deregulated c-MYC expression in human colon carcinoma cells by chromosome 5 transfer. 总被引:3,自引:1,他引:2 下载免费PDF全文
C Rodriguez-Alfageme E J Stanbridge S M Astrin 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(4):1482-1486
Two-thirds of sporadic colon carcinomas express elevated levels of the c-MYC protooncogene. In addition, most colon carcinoma cell lines show constitutive elevated expression (10- to 40-fold over normal) of MYC RNA and protein that is not modulated in response to a mitogenic stimulus. Indirect immunofluorescence has been used to detect c-MYC protein in such cell lines, in hybrid cells resulting from fusions of such lines with cells that regulate MYC normally, and in carcinoma cells to which a normal copy of chromosome 5 has been transferred by microcell fusion. The deregulated expression of c-MYC is suppressed by fusion with a cell that regulates MYC normally. In addition, transfer of chromosome 5 by microcell fusion results in suppression of deregulated expression. Suppressed cells are no longer tumorigenic in nude mice. Loss of the transferred chromosome results in reexpression of the tumorigenic phenotype and in constitutive elevated expression of MYC. These data indicate that function of a tumor-suppressor gene on chromosome 5 is necessary for the regulated expression of MYC in at least some colon cells. Loss of this suppressor results in deregulated MYC expression and is a necessary, but most likely not sufficient, event for the expression of the tumorigenic phenotype in a subset of colon carcinomas. 相似文献
48.
Igor Kissin Rex Stanbridge Sanford P. Bishop J. G. Reves 《Journal canadien d'anesthésie》1981,28(3):239-243
The effect of halothane on myocardial infarction caused by ligation of the left descending coronary artery was studied in rats. The extent of infarction was quantified 48 hours after ligation of the artery by planimetric measurement of left ventricular slices stained with nitrobluetetrazolium. Animals exposed to halothane one per cent for three hours after the coronary ligation were compared with a control group which received halothane for only 5-7 minutes during surgery. It was found that halothane caused a small increase in infarction size (31.3 ± 1.5 per cent of the left ventricle compared to 25.7 ± 2.3 percent, p < 0.05). This effect was accompanied by a decrease in systolic blood pressure (91 ± 2 mmHg compared to 113 ± 3 mm Hg, p < 0.001). Heart rate did not change significantly. Analysis of our results in comparison to previously reported data on the effect of halothane on myocardial ischaemia in different experimental conditions shows that halothane may produce beneficial as well as detrimental effects on ischaemic injury to the myocardium. The latter can result when the drug causes marked hypotension in the absence of a significant decrease in heart rate. 相似文献
49.
Analysis of malignancy in human cells: malignant and transformed phenotypes are under separate genetic control. 总被引:3,自引:0,他引:3 下载免费PDF全文
E J Stanbridge J Wilkinson 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(3):1466-1469
Human cell hybrids derived from malignant HeLa and normal fibroblast parental cells expressed many of the transformed properties of the HeLa parent but their tumor-producing capability was suppressed. Hybrids derived from HeLa/HeLa fusions retained both their transformed and malignant phenotypes. Thus, an apparent separation of the control of the transformed versus malignant phenotype is indicated. Furthermore, several transformed properties--including lack of density-dependent inhibition of growth, lectin agglutination, lowered requirement for serum growth factors, and anchorage independence--are expressed coordinately in the nontumorigenic hybrids. This finding suggests that none of these properties by themselves, or in concert, endows a cell with tumorigenic potential. 相似文献