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991.
AIM: To investigate the prevalence, risk factors, and selection of the study population for cholecystolithiasis in an urban population in Germany, in relation to our own findings and to the results in the international literature. METHODS: A total of 2 147 persons (1 111 females, age 42.8±12.7 years; 1 036 males, age 42.3±13.1 years) participating in an investigation on the prevalence of Echinococcus multilocularis were studied for risk factors and prevalence of gallbladder stone disease. Risk factors were assessed by means of a standardized interview and calculation of body mass index (BMI). A diagnostic ultrasound examination of the gallbladder was performed. Data were analyzed by multiple logistic regression, using the SAS statistical software package. RESULTS: Gallbladder stones were detected in 171 study participants (8.0%, n = 2 147). Risk factors for the development of gallbladder stone disease included age, sex, BMI, and positive family history. In a separate analysis of female study participants, pregnancy (yes/no) and number of pregnancies did not exert any influence. CONCLUSION: Findings of the present study confirm that age, female sex, BMI, and positive family history are risk factors for the development of gallbladder stone disease. Pregnancy and the number of pregnancies, however, could not be shown to be risk factors. There seem to be no differences in the respective prevalence for gallbladder stone disease in urban and rural populations.  相似文献   
992.
A set of problem solving strategies integrated into nursing process in nursing core courses (PSNP) was developed for students enrolled in a post-RN baccalaureate nursing program (RN-BSN) in a university in Taiwan. The purpose of this study, therefore, was to evaluate the effectiveness of PSNP on students' clinical problem solving abilities. The one-group post-test design with repeated measures was used. In total 114 nursing students with 47 full-time students and 67 part-time students participated in this study. The nursing core courses were undertaken separately in three semesters. After each semester's learning, students would start their clinical practice, and were asked to submit three written nursing process recordings during each clinic. Assignments from the three practices were named post-test I, II, and III sequentially, and provided the data for this study. The overall score of problem solving indicated that score on the post-test III was significantly better than that on post-test I and II, meaning both full-time and part-time students' clinical problem solving abilities improved at the last semester. In conclusion, problem-solving strategies integrated into nursing process designed for future RN-BSN students are recommendable.  相似文献   
993.
The objective of the study was to test the hypothesis that serum levels of cartilage oligomeric matrix protein (COMP) would decrease and serum levels of tumor‐necrosis factor alpha (TNF‐α) and selected matrix metalloproteinases (MMPs) would increase in response to bed rest (BR) and that these changes are unaffected by the intake of potassium bicarbonate or whey protein. Seven and nine healthy male subjects participated in two 21‐day 6° head down tilt crossover BR‐studies with nutrition interventions. Serum samples were taken before, during, and after BR and biomarker concentrations were measured using commercial enzyme‐linked immunosorbent assays. MMP‐3 during BR was significantly lower than at baseline (reduction greater 20%; p < 0.001). MMP‐3 increased significantly from 14 to 21 days of BR (+7%; p = 0.049). COMP during BR was significantly lower than at baseline (reduction greater 20%; p < 0.001). MMP‐3 and COMP returned to baseline within 1 day after BR. MMP‐9 on day 3 of BR was significantly lower than at baseline (?31%; p < 0.033) and on days 3, 5, and 14 of BR significantly lower than at the end of and after BR (reduction greater 35%; p < 0.030). The nutritional countermeasures did not affect these results. The observed changes in cartilage biomarkers may be caused by altered cartilage metabolism in response to the lack of mechanical stimulus during BR and inflammatory biomarkers may play a role in changes in biomarker levels. Clinical relevance: Immobilization independently from injury can cause altered cartilage biomarker concentration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1465–1471, 2018.
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994.
脂肪乳对内毒素诱导急性肺损伤小鼠的干预作用   总被引:1,自引:1,他引:1  
目的比较以橄榄油为主的脂肪乳Clinoleic20%和豆油为主的脂肪乳Lipoven20%对脂多糖(LPS)诱导急性肺损伤(ALI)小鼠炎症反应的作用。方法雄性Balb/C小鼠按随机数字表法分为生理盐水(NaCl)、Clino和Lipo3组。用微量泵分别向3组小鼠泵入质量分数为0,9%的NaCl、20%Clinoleic和20%Lipoven,并在进行取血和肺泡灌洗前8h和24h向气管内喷洒LPS制备ALI模型。观察3组小鼠LPS诱导8h和24h时的存活率、肺组织湿/干重比、支气管肺泡灌洗液(BALF)中白细胞计数、肿瘤坏死因子-α(TNF—α)、巨噬细胞炎性蛋白-2(MIP-2)、肺组织髓过氧化物酶(MPO)活性及血清花生四烯酸(AA)、油酸、亚油酸含量。结果LPS诱导后可引起BALF中自细胞计数、TNF—α、MIP2,肺组织MPO活性、w/D比例及血清AA水平显著升高。Lipoven显著降低ALI小鼠24h后的存活率(P均<0.01),而Clino组与NaCl组之间差异无显著性;肺组织MPO活性在24h后两个脂肪乳组明显高于NaCl组(P均<0.01),而两个脂肪乳之间差异无显著性。注射ALI 8h后,Lipo组BALF中MIP-2和血清AA均较NaCl组和Clino组升高,24h后BALF中白细胞、TNF—α、AA水平也均显著高于NaCl组和Clino组(P均<0.01);而肺组织水肿程度和油酸、亚油酸含量在3组间比较差异均无显著性。结论Lipoven20%加重ALI小鼠的炎症反应,降低实验动物的存活率,可能与其增加AA产生有关;而Clinoleic20%对炎症反应的影响较轻。  相似文献   
995.
BACKGROUND. In some active multiple sclerosis (MS) lesions, a strong immune reaction at the lesion edge may contain growth and thereby isolate the lesion from the surrounding parenchyma. Our previous studies suggest that this process involves opening of the blood-brain barrier in capillaries at the lesion edge, seen on MRI as centripetal contrast enhancement and a colocalized phase rim. We hypothesized that using these features to characterize early lesion evolution will allow in vivo tracking of tissue degeneration and/or repair, thus improving the evaluation of potential therapies for chronic active lesions.METHODS. Centripetally and centrifugally enhancing lesions were studied in 17 patients with MS using 7-tesla MRI. High-resolution, susceptibility-weighted, T1-weighted (before/after gadolinium), and dynamic contrast–enhanced scans were acquired at baseline and months 1, 3, 6, and 12. For each lesion, time evolution of the phase rim, lesion volume, and T1 hypointensity were assessed. In autopsies of 3 progressive MS cases, the histopathology of the phase rim was determined.RESULTS. In centripetal lesions, a phase rim colocalized with initial contrast enhancement. In 12 of 22, this phase rim persisted after enhancement resolved. Compared with centripetal lesions with transient rim, those with persistent rim had less volume shrinkage and became more T1 hypointense between months 3 and 12. No centrifugal lesions developed phase rims at any time point. Pathologically, persistent rims corresponded to an iron-laden inflammatory myeloid cell population at the edge of chronic demyelinated lesions.CONCLUSION. In early lesion evolution, a persistent phase rim in lesions that shrink least and become more T1 hypointense over time suggests that the rim might mark failure of early lesion repair and/or irreversible tissue damage. In later stages of MS, phase rim lesions continue to smolder, exerting detrimental effects on affected brain tissue.TRIAL REGISTRATION. NCT00001248.FUNDING. The Intramural Research Program of NINDS supported this study.  相似文献   
996.
997.
998.
Malignant gliomas are the most frequent primary brain tumors and have a dismal prognosis due to their infiltrative growth. Gene therapy using viral vectors represents an attractive alternative to conventional cancer therapies. In a previous study, we established lentiviral vectors pseudotyped with lymphocytic choriomeningitis virus (LCMV) glycoproteins (GPs) and demonstrated transduction of human malignant glioma cells in culture. In the current approach, we compared the transduction efficacy of LCMV-GP- and vesicular stomatitis virus glycoprotein (VSV-G)-pseudotyped lentiviral vectors for malignant glioma cells and normal brain cells in vitro and in vivo. LCMV-GP pseudotypes transduced almost exclusively astrocytes, whereas VSV-G pseudotypes infected neurons as well as astrocytes. LCMV-GP pseudotypes showed an efficient transduction of solid glioma parts and specific transduction of infiltrating tumor cells. In contrast, VSV-G-pseudotyped lentiviral vectors transduced only a few tumor cells in solid tumor parts and infected mostly normal brain cells in infiltrating tumor areas. In conclusion, lentiviral vectors pseudotyped with LCMV glycoproteins represent an attractive option for gene therapy of malignant glioma.  相似文献   
999.
BACKGROUND: The accurate and rapid recognition of myocardial injury in patients presenting in the emergency department (ED) with chest pain continues to be a clinical challenge. Heart-type fatty acid-binding protein (H-FABP) appears to be one of the best candidates among the new early cardiac markers studied. METHODS: We evaluated the analytical characteristics of a new quantitative and fully automated H-FABP assay (Randox Laboratories Ltd., Crumlin, UK) and compared its clinical performance with respect to the myoglobin (Myo) assay (Dade Behring, Milan, Italy). A precision study was carried out by testing three levels of quality control (QC) material and two in-house pool (P) samples. To test the accuracy of H-FABP determinations in plasma (lithium-heparin) samples, H-FABP concentrations measured in a set of matched sera and plasma samples were compared. A total of 77 non-consecutive patients (51 males and 26 females; 62+/-16 years) who presented to the ED with chest pain suggesting myocardial ischemia were enrolled. The patients were classified into two groups (acute myocardial infarction, n=22; non-acute myocardial infarction, n=55) on the basis of the discharge diagnosis. RESULTS: The between-day imprecision for three levels of control material and serum pool samples was 6.26%-8.04% (range 2.32-44.03 microg/L) and 9.03%-12.63% (range 11.85-65.13 microg/L), respectively. In the serum vs. plasma study, bias was +0.178 (95% CI -0.033 to +0.389). The best cut-off and the associated diagnostic efficacy were 95 microg/L and 89.47% for Myo and 5.09 microg/L and 98.70% for H-FABP, respectively. CONCLUSIONS: H-FABP determination in patients with ischemic symptoms may be a more reliable early indication of cardiac damage than myoglobin.  相似文献   
1000.
OBJECTIVE: Cilostazol is an antiplatelet agent with vasodilating properties. It has been used to treat patients with peripheral ischemia, such as intermittent claudication. We used a pharmacokinetic-pharmacodynamic model to analyze the relation between the plasma concentration of cilostazol, the inhibitory effect of the drug on platelet aggregation, and the cardiovascular effects of the drug on healthy humans. METHODS: A single oral dose of 100 mg cilostazol was administered to 20 healthy volunteers. Serial blood sampling and pharmacodynamic measurements were performed up to 48 hours thereafter. The effects of cilostazol on platelet aggregation, blood pressure, and heart rate were measured during the same period. The plasma concentration of cilostazol was measured with a validated HPLC method that entailed ultraviolet detection. The time courses of plasma cilostazol concentration, platelet aggregation, and cardiovascular effects were analyzed by means of pharmacokinetic-pharmacodynamic modeling with the program ADAPT II. RESULTS: The plasma concentration-time course followed a 2-compartment model. Mean peak concentration was 775 ng/ml approximately 3.65 hours after administration of cilostazol. The maximal effect on platelet aggregation was a 31.14% reduction 6.05 hours after administration. No significant difference in systolic blood pressure was found. The maximal increase in heart rate was 13.49%, whereas the maximal decrease in diastolic blood pressure was 29.51%. Both peak effects were detected approximately 6 hours after administration of the drug. Platelet aggregation and cardiovascular effects (change in diastolic blood pressure and heart rate) were analyzed with the effect-link sigmoid maximal effect model. CONCLUSION: This pharmacokinetic-pharmacodynamic model successfully described the relation between plasma concentration of cilostazol and the antiplatelet and cardiovascular effects of the drug.  相似文献   
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