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131.
Rigano D Grassia A Bruno M Rosselli S Piozzi F Formisano C Arnold NA Senatore F 《Journal of natural products》2006,69(5):836-838
From the aerial parts of Marrubium globosum ssp. libanoticum, seven labdane diterpenoids were isolated. Three of them are new natural products [(13R)-9alpha,13alpha-epoxylabda-6beta(19),16(15)-diol dilactone (2), deacetylvitexilactone (7), marrulanic acid (8)], whereas the other four, namely, (13S)-9alpha,13alpha-epoxylabda-6beta(19),16(15)-diol dilactone (1), cyllenin A (3), 15-epi-cyllenin A (4), and marrulibanoside, are previously known compounds. The structures of 2, 7, and 8 were determined by spectroscopic and chemical methods. 相似文献
132.
Twenty-four patients with inflammatory lesions of the abdominal wall were examined by ultrasonography. Nine of these patients underwent computed tomographic (CT) scanning as well. Both ultrasonography and CT clearly delineated the exact location and extent of abdominal wall abscesses. Abscesses were easily differentiated from cellulitis or phlegmon with ultrasound. The peritoneal line was more clearly delineated on ultrasonograms than on CT scans; abscesses were also more distinct on the ultrasonograms because of their low echogenicity compared with the surrounding structures. Gas bubbles, fat density with specific low attenuation values, and underlying inflamed bowel loops in obese patients with Crohn's disease were better delineated by CT. 相似文献
133.
134.
J I Hirsch J L Tatum M J Fratkin D L Apostolides R I Quint 《Journal of nuclear medicine》1989,30(7):1257-1263
Stannous fluoride colloid (SFC) kits for instant radiolabeling with 99mTc were prepared and evaluated for suitability as a leukocyte radiolabeling agent. Technetium-99m labeling for kits stored at -15 degrees C for up to 3 mo was greater than 95% as determined by instant thin layer chromatography while colloid particles of 1-3 microns were measured by electron microscope for these preparations. Canine leukocyte preparations labeled with [99mTc]SFC and characterized by triple density gradients of metrizamide in plasma demonstrated an 83% leukocyte association. Analysis of labeled cell preparation for up to 3 hr demonstrated label stability. Labeled leukocytes, when readministered in normal dogs, demonstrated bi-exponential blood clearance with uptake and subsequent clearance from lung. There was increasing uptake of labeled leukocytes by the liver until steady state was achieved. Furthermore, when whole blood samples were analyzed by the triple density gradient method, an increasing monocyte-to-granulocyte ratio was observed to occur with time. By 3 hr 95% of the whole blood activity was associated with the leukocyte fraction. Dogs in which a 24-hr sterile abscess was created demonstrated elevated blood-pool activity as compared to control with localization of the labeled cells at inflammatory sites within 3 hr following cell readministration. 相似文献
135.
136.
A Hirsch F Windhausen JG Tijssen AJ Oude Ophuis WJ van der Giessen PM van der Zee JH Cornel FW Verheugt RJ de Winter 《European heart journal》2009,30(6):645-654
AIMS: In several observational studies, revascularization is associated with substantial reduction in mortality in patients with non-ST-segment elevation acute coronary syndrome (nSTE-ACS). This has strengthened the belief that routine early angiography would lead to a reduction in mortality. We investigated the association between actual in-hospital revascularization and long-term outcome in patients with nSTE-ACS included in the ICTUS trial. METHODS AND RESULTS: The study population of the present analysis consists of ICTUS participants who were discharged alive after initial hospitalization. The ICTUS trial was a randomized, controlled trial in which 1200 patients were randomized to an early invasive or selective invasive strategy. The endpoints were death from hospital discharge until 4 year follow-up and death or spontaneous myocardial infarction (MI) until 3 years. Among 1189 patients discharged alive, 691 (58%) underwent revascularization during initial hospitalization. In multivariable Cox regression analyses, in-hospital revascularization was independently associated with a reduction in 4 year mortality and 3 year event rate of death or spontaneous MI: hazard ratio (HR) 0.59 [95% confidence interval (CI) 0.37-0.96] and 0.46 (95% CI 0.31-0.68). However, when intention-to-treat analysis was performed, no differences in cumulative event rates were observed between the early invasive and selective invasive strategies: HR 1.10 (95% CI 0.70-1.74) for death and 1.27 (95% CI 0.88-1.85) for death or spontaneous MI. CONCLUSION: The ICTUS trial did not show that an early invasive strategy resulted in a better outcome than a selective invasive strategy in patients with nSTE-ACS. However, similar to retrospective analyses from observational studies, actual revascularization was associated with lower mortality and fewer MI. Whether an early invasive strategy leads to a better outcome than a selective invasive strategy cannot be inferred from the observation that revascularized patients have a better prognosis in non-randomized studies. 相似文献
137.
BackgroundGenetic markers of muscle inflammation (eg, tumour necrosis factor α [TNFα] and interleukin [IL] 6 are downregulated following repeated transient increases after bouts of exercise. Total hip replacement (THR) typically resolves preoperative pain, although strength deficits of 10–21% persist in the affected hip at 1 year postoperatively. This study assessed whether mRNA expression of TNFα and IL6 in the vastus lateralis (VL) of the operated leg was related to changes in the strength of the operated leg quadriceps in patients following THR.MethodsTen patients were recruited prospectively after ethical approval. Distal VL (5 cm proximal to lateral suprapatellar pouch) biopsy samples were obtained intraoperatively and at 6 weeks postoperatively, with maximal voluntary contraction of the operated leg quadriceps (MVCOLQ) in Newtons (N), assessed preoperatively and at 6 weeks postoperatively. RT-PCR was used to assess mRNA expression in the biopsy samples and associations evaluated with Spearman's correlation coefficient.FindingsMean mRNA relative quotient (RQ) for comparison of 6 week intraoperative VL samples was 6·23 [SD 12·85] for TNFα and 17·10 [47·46] for IL6. Preoperatively, mean MVCOLQ was 188·90 N [76·84] and at 6 weeks it was 217·00 N [53·91]. There was no significant relation between TNFα or IL-6 RQ and absolute MVCOLQ at 6 weeks (r=0·115 [p=0·376] and ?0·491 [p=0·075], respectively). No statistically significant relation existed between TNFα mRNA RQ and the improvement in MVCOLQ at 6 weeks (r=–0·498, p=0·071) nor with IL6 and the same measure (r=0·091, p=0·401).InterpretationThere is a trend to correlation that exists for improvement in MVCOLQ with a reduction in TNFα mRNA expression, as well as between absolute MVCOLQ and reduction in IL-6 mRNA expression at 6 weeks postoperatively. Improvement in muscle strength may be mediated by reduced muscle inflammation and the associated reduction in pain in patients with severe osteoarthritis.FundingWales Deanery and Betsi Cadwaladr University Health Board Small Grants Scheme. 相似文献
138.
Savelberg HH Vorstenbosch MA Kamman EH van de Weijer JG Schambardt HC 《Gait & posture》1998,7(1):26-34
For overground and treadmill locomotion to be mechanically similar, it is required that the belt speed of the treadmill is constant and the same to that of overground locomotion. Variation of the belt speed during a stride causes exchange of energy between the subject and the treadmill. This might be the cause of different kinematic patterns between overground and treadmill locomotion, which have been reported in literature. The aim of this study was to investigate whether the intra-stride belt-speed is variable, and whether differences in kinematic patterns can be attributed to these variations. Nine subjects walked and ran overground and on two treadmills that were differently susceptible to subjects' braking and accelerating forces. It was found that the speed variations during treadmill locomotion affect the kinematic parameters significantly. The amount of intra-stride belt-speed variation was found to depend on the power of the treadmill and the mass of the subject. Copyright 1998 Elsevier Science B.V. 相似文献
139.
DD McMillan SK Lee M Serediak JG Finn S Saigal CR Walker 《Paediatrics & child health》1999,4(1):51-56
There have been publically expressed concerns about the costs and allocation of neonatal and perinatal health care resources in Canada and elsewhere for the past 15 years. This paper reports information from a symposium held during the 1996 Canadian Paediatric Society (CPS) annual meeting sponsored by the CPS Section on Perinatal Medicine. Experts in perinatal epidemiology, health care economics, public policy and finance, and consumer perspectives on the outcomes of neonatal and perinatal intensive care explored the following questions: How should the need for health care resources in the neonatal and perinatal area be objectively determined? When there are competing needs between the maternal-newborn area and other areas, how should these be rationalized? What evidence should be used (or should be available) to support the present use of resources? What evidence should be available (or is needed) to change or introduce new uses of resources? The conclusions indicated that there are no generally accepted methods to determine the allocation of health care resources but that considerations need to include population characteristics, desired outcomes, achievable results, values, ethics, legalities, cost-benefit analyses and political objectives. Information from families and adolescents who required the use of high technology and/or high cost programs will contribute individual, family and societal values that complement cost-efficacy analyses. 相似文献
140.
银杏叶醇提取物对异烟肼和利福平肝毒性保护作用的实验研究 总被引:5,自引:1,他引:4
目的 :观察银杏叶醇提取物对异烟肼和利福平肝毒性的保护作用及其机制探讨。方法 :分别测定肝损害组和银杏叶醇提取物大、小剂量组小鼠的血清谷丙转胺酶 (SGPT)、肝指数、肝匀浆丙二醛 (MDA)含量、肝微粒体P4 50和线粒体Ca2 ATP酶活性 ,以及肝病理检查 ,并与对照组比较。结果 :银杏叶醇提取物大、小剂量均可对抗异烟肼和利福平引起的MDA、SGPT、肝微粒体P4 50 的增高 (P <0 .0 5) ,以及对抗其引起的形态学改变 ;银杏叶醇提取物大剂量对抗其线粒体Ca2 ATP酶活性的降低。结论 :银杏叶醇提取物可对抗异烟肼和利福平所致肝毒性。 相似文献