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排序方式: 共有593条查询结果,搜索用时 15 毫秒
41.
The J-curve phenomenon and the treatment of hypertension. Is there a point beyond which pressure reduction is dangerous? 总被引:5,自引:0,他引:5
We critically appraised the medical literature to evaluate whether there is a point beyond which blood pressure reduction in hypertensive subjects is no longer beneficial and possibly even deleterious. Thirteen studies that stratified cardiovascular outcomes by level of achieved blood pressure in treated hypertensive subjects who had been followed up for at least 1 year were critiqued by four independent reviewers. Data addressing population, protocol, and methodological characteristics were evaluated. Studies did not show a consistent J-shaped relationship between treated blood pressure and stroke, but they did demonstrate a consistent J-shaped relationship for cardiac events and diastolic blood pressure. The beneficial therapeutic threshold point was 85 mm Hg. We conclude that low treated diastolic blood pressure levels, ie, below 85 mm Hg, are associated with increased risk of cardiac events. 相似文献
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耐力训练过程中大鼠体内糖储备及胰岛激素变化与黄芪、生脉穴位注射的干预效应 总被引:3,自引:0,他引:3
目的:穴位注射疗法在临床应用较多,但在运动医学领域研究不多。观察穴位注射黄芪、生脉对耐力训练大鼠糖储备和运动能力的影响。方法:实验于2004-07在陕西师范大学完成。①实验分组:健康雄性SD大鼠32只,体质量180~220g,随机抽签法分为安静对照组、训练对照组、生理盐水组、药物注射组,每组8只。②实验方法:建立穴位注射黄芪、生脉大鼠的耐力跑台训练实验模型,安静对照组安静笼饲养。训练对照组、生理盐水组、药物注射组先于动物跑台上进行5周适应性训练,之后跑速每周递增,5d/周,共5周;然后进行2周的大强度耐力训练,30min/d,7d/周,共2周。训练对照组、生理盐水组、药物注射组第8周第1天以速度为35m/min运动至力竭。③实验评估:7周后取材测定肝糖原、肌糖原、血清胰岛素、胰高血糖素的变化。实验中对动物处置符合动物伦理学标准。结果:纳入大鼠32只,均进入结果分析。①通过大强度耐力训练,药物注射组与其他3组相比,肝糖原含量均升高(P<0.05);训练对照组肌糖原比安静对照组降低(P<0.05),生理盐水组与训练对照组相比则显著性升高(P<0.01)。②训练对照组胰岛素比安静对照组明显降低(P<0.01);生理盐水组及药物注射组都能抑制这种降低的趋势(P<0.01);药物注射组胰高血糖素较安静对照组、训练对照组要高,且有显著性差异(P<0.01)。结论:穴位注射黄芪、生脉使大强度耐力训练大鼠体内糖储备显著增加,同时可以提高胰岛激素水平,从而提高了大鼠的运动能力。 相似文献
45.
Sonography was used to investigate left-right asymmetries of the brain in 66 human neonates with gestational ages of 28-44 wk. The body of the left lateral ventricle was larger than the right in 21 infants (31.8%), whereas the right was larger than the left in only four infants (6.1%)(p less than 0.001). Asymmetry of the lateral ventricles can be detected in the normal neonatal brain using sonography. 相似文献
46.
Karasu Z Akyildiz M Kilic M Zeytunlu M Aydin U Tekin F Yilmaz F Ozacar T Akarca U Ersoz G Gunsar F Ilter T Lucey MR 《Journal of gastroenterology and hepatology》2007,22(12):2124-2129
BACKGROUND AND AIM: Living donor liver transplantation (LDLT) has particular advantages for Turkey where hepatitis B virus (HBV) infection is the most common cause of cirrhosis, both because LDLT circumvents the difficulties encountered in the emerging world in providing deceased donor organs, and because it allows preemptive antiviral therapy. The aim of this study was to review one institution's experience with LDLT in patients with chronic HBV infection. METHODS: A total of 109 patients with chronic HBV infection underwent LDLT between September 1999 and June 2005, of whom 40 were coinfected with hepatitis D virus and 23 had hepatocellular carcinoma. Antiviral prophylaxis was attempted in all, beginning prior to transplantation with lamivudine or adefovir, and continuing after transplantation with low dose intramuscular hyperimmune B immunoglobulin (HBIg) plus lamivudine or adefovir. RESULTS: In a median follow up of 20 months (range 1-66 months), there was no donor mortality. One-year recipient survival was 90%, and in total 16 recipients died. None of the deaths was related to HBV. Recurrence of HBV infection was detected by reappearance of serum hepatitis B surface antigen in six patients (5.5%) at 5, 8, 12, 17, 34 and 46 months after transplantation, respectively. There was no influence of donor hepatitis B core antibody status on the likelihood of recurrence of HBV in the allograft. CONCLUSION: The results indicate that LDLT with antiviral treatment and low dose HBIg provides excellent results for donors and recipients. 相似文献
47.
Das RR Lucey BP Chou SH Espinosa PS Zamani AA Dworetzky BA Bromfield EB Lee JW 《Neurocritical care》2009,10(3):368-372
We investigated the feasibility and utilization of conductive plastic electrodes (CPEs) in patients undergoing continuous
video-electroencephalographic (EEG) monitoring in the intensive care unit (ICU), and assessed the quality of brain magnetic
resonance imaging (MRI) and computed tomography (CT) images obtained during this period. A total of 54 patients were monitored.
Seizures were recorded in 16 patients. Twenty-five patients had neuroimaging performed with electrodes in place; 15 MRI and
23 CT scans were performed. All patients had excellent quality anatomical images without clinically significant artifacts,
and without any signs or symptoms that raised safety concerns. Recording quality of the EEG was indistinguishable to that
achieved with standard gold electrodes. The use of CPEs allowed for uninterrupted EEG recording of patients who required urgent
neuroimaging, and decreased the amount of time spent by the technologists required to remove and reattach leads. 相似文献
48.
D Altavilla F Squadrito A Bitto F Polito BP Burnett V Di Stefano L Minutoli 《British journal of pharmacology》2009,157(8):1410-1418
Background and purpose:
The flavonoids, baicalin and catechin, from Scutellaria baicalensis and Acacia catechu, respectively, have been used for various clinical applications. Flavocoxid is a mixed extract containing baicalin and catechin, and acts as a dual inhibitor of cyclooxygenase (COX) and 5-lipoxygenase (LOX) enzymes. The anti-inflammatory activity, measured by protein and gene expression of inflammatory markers, of flavocoxid in rat peritoneal macrophages stimulated with Salmonella enteritidis lipopolysaccharide (LPS) was investigated.Experimental approach:
LPS-stimulated (1 µg·mL−1) peritoneal rat macrophages were co-incubated with different concentrations of flavocoxid (32–128 µg·mL−1) or RPMI medium for different incubation times. Inducible COX-2, 5-LOX, inducible nitric oxide synthase (iNOS) and inhibitory protein κB-α (IκB-α) levels were evaluated by Western blot analysis. Nuclear factor κB (NF-κB) binding activity was investigated by electrophoretic mobility shift assay. Tumour necrosis factor-α (TNF-α) gene and protein expression were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively. Finally, malondialdehyde (MDA) and nitrite levels in macrophage supernatants were evaluated.Key results:
LPS stimulation induced a pro-inflammatory phenotype in rat peritoneal macrophages. Flavocoxid (128 µg·mL−1) significantly inhibited COX-2 (LPS = 18 ± 2.1; flavocoxid = 3.8 ± 0.9 integrated intensity), 5-LOX (LPS = 20 ± 3.8; flavocoxid = 3.1 ± 0.8 integrated intensity) and iNOS expression (LPS = 15 ± 1.1; flavocoxid = 4.1 ± 0.4 integrated intensity), but did not modify COX-1 expression. PGE2 and LTB4 levels in culture supernatants were consequently decreased. Flavocoxid also prevented the loss of IκB-α protein (LPS = 1.9 ± 0.2; flavocoxid = 7.2 ± 1.6 integrated intensity), blunted increased NF-κB binding activity (LPS = 9.2 ± 2; flavocoxid = 2.4 ± 0.7 integrated intensity) and the enhanced TNF-α mRNA levels (LPS = 8 ± 0.9; flavocoxid = 1.9 ± 0.8 n-fold/β-actin) induced by LPS. Finally, flavocoxid decreased MDA, TNF and nitrite levels from LPS-stimulated macrophages.Conclusion and implications:
Flavocoxid might be useful as a potential anti-inflammatory agent, acting at the level of gene and protein expression. 相似文献49.