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941.
BACKGROUND: The magnitudes of the first (WI1) and the second wave-intensity peak (WI2) during the ejection period can be used as indices of left ventricular (LV) contractility and relaxation, respectively. However, use of WI to characterize LV dp/dt and the end-diastolic volume (V ed) relationship may be more problematic, as WI may be affected by changes in preload. METHODS AND RESULTS: The LV pressure-volume data sets, consisting of 23 recordings obtained by the conductance method from 12 heart disease patients, were studied. End-systolic elastance (E es) and volume-axis-intercept (V0) were calculated with varying preload. Time constant of LV relaxation (tau), V ed, and WI were calculated from steady-state averaged data. The E es showed a weak correlation with WI1 (r = 0.46, p < 0.05) but a better correlation with preload-adjusted WI1 [WI1/V ed; r=0.86, WI1/V(ed)2; r = 0.92, WI1/(V ed - V0)2; r = 0.89, all p < 0.01]. Similarly, tau did not correlate with WI2 but did correlate with preload-adjusted WI2 [WI2/V ed; r = -0.73, WI2/V(ed) 2; r = -0.63, WI2/(V ed - V0)2; r = -0.78, all p < 0.01]. CONCLUSIONS: These data demonstrate the importance of preload-adjustment when using the WI index for simultaneous assessment of LV contractility and relaxation.  相似文献   
942.
蚤莲合剂对DEN所致大鼠肝癌前病变的影响   总被引:2,自引:1,他引:2  
目的:观察蚤莲合剂对诱发大鼠原发性肝癌的抗促癌作用及其机理。方法:以含100ppm的二乙基亚硝胺(DEN)饮水造模,采用蚤莲合剂灌胃给药,观察其对大鼠肝组织病理学、免疫组化、血清和肝组织生物化学指标的影响。结果:蚤莲合剂对大鼠肝组织癌前病变有抑制作用。大鼠肝癌形成率相对减少,血清ALT、ALb、ALP、TNF水平及肝匀浆γ-GT活性明显低于模型组(P<0.01),其免疫组化AFP阳性细胞数也较模型组为少(P<0.05)。结论:蚤莲合剂有明显抑制DEN所致大鼠肝癌前病变的作用,其抑癌作用可能与其护肝、抗炎和控制变异细胞过度合成有关。  相似文献   
943.
944.
Epidemics of enterovirus 71 infections caused the rapid death of many children in Malaysia in 1997 and in Taiwan in 1998. Pulmonary edema occurred in most of the fatal cases and was considered to be neurogenic. The role of the heart was rarely investigated before. Between January 1998-January 2001, 34 consecutive patients who were admitted to the intensive care unit due to enterovirus infection were studied prospectively. Patients were divided into two groups: group I with pulmonary edema, and group II without pulmonary edema. Comparisons were made between the two groups based upon demographic, neurological, and cardiovascular manifestations. Group I consisted of 11 patients (5 boys, 6 girls; mean age, 22.8 months), and group II of 23 patients (12 boys, 11 girls; mean age, 28.8 months). There were no significant differences between the two groups in comparing sex, age, body weight, neurological severity, intracranial pressure, cell count, protein and glucose levels in cerebral spinal fluid, and blood pressure. All group I patients had left ventricular dysfunction, and their ejection fractions were significantly lower than those of patients in group II (37 +/- 11% vs. 75 +/- 6%, P < 0.001). Group I heart rates were higher than those of group II (175 +/- 24 vs. 137 +/- 25, P < 0.001). In group I, 9 patients who received conventional treatment died, and the only two survivors received left ventricular assist devices. In conclusion, the pulmonary edema of fulminant enterovirus 71 infection is associated with left ventricular failure. Left ventricular function is the major determinant of outcome. Early recognition of heart failure and aggressive cardiac intervention are life-saving. Pediatr Pulmonol. 2003; 35:263-268.  相似文献   
945.
目的观察重组人Ⅱ型肿瘤坏死因子受体.抗体融合蛋白(rhTNFR:Fc,益赛普)联合甲氨蝶呤(methotrexate,MTX)对改善病情抗风湿药(disease—modifying antirheumatic drug,DMARD)无效类风湿关节炎(rheumatoid arthritis,RA)患者的疗效。方法DMARD治疗效果不佳的活动性RA患者64例,根据患者性别、年龄、病程及疾病活动程度将患者随机分为具有可比性的两组。试验组32例,予每周2次皮下注射rhTNFR:Fc 25mg/次.同时口服MTX 15mg/周;对照组32例,13服泼尼松5~10mg/d,同时口服MTX1 5mg/周。疗程12周。疗效评价采用美国风湿病学会(ACR)疗效评定标准。结果治疗第4、8和12周,试验组ACR20有效率(45.2%、54.8%和64.5%)均显著高于对照组(16.1%、19.4%和22.6%)(P〈0.05)。治疗第8和12周试验组ACR50有效率亦显著高于对照组(P〈0.05)。结论相对于应用小剂量激素联合甲氨蝶呤,rhTNFR:Fc联合甲氨蝶呤治疗DMARD无效的RA效果更佳。  相似文献   
946.
对于需要闭塞载瘤动脉的难治性颅内动脉瘤,血管重建技术是解决脑血流代偿不足的良好方法.随着显微手术技术的发展,移植血管通畅率的不断提高,血管重建治疗难治性颅内动脉瘤的疗效也在不断提高.  相似文献   
947.
948.
This study aimed to examine the effects of the recombinant human somatotropin (rhGH) on protecting neuronal function, and improving learning and memory deficits in mice. Mice were intracerebroventricularly (icv) injected with the aggregated amyloid beta-peptide (Abeta) to mimic the Alzheimer's disease (AD). The learning and memory functions in mice were examined by the step through test (an index of long-term memory) and the water maze performance (an index of spatial recognition memory). The results indicated that the mice treated with rhGH showed significant reduction of the error counts and the long memory retentions in the step-through test, and short swimming times in the water maze performance. Toxic effects of free radicals, damages of cholinergic neurons, and increased lipid peroxidation appeared in the cerebra of Abeta-treated mice, manifesting an increase of malondialdehyde (MDA) and decline of glutathione (GSH) level, an increment of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities, and a reduction of the acetylcholine (ACh) level. The gel electrophoresis pattern of the cerebra of mice treated with Abeta showed a typical DNA ladder of apoptosis. The in vivo experiments showed that the rhGH treatment significantly reversed the elevated MDA, ChAT, AChE, and the decreased GSH, ACh levels in the Abeta model mice. The results suggested that there were potential uses of the neuroprotective action of rhGH in the remedy of AD.  相似文献   
949.
Liu JM  Cai XZ  Lin JJ  Fu ZQ  Yang GZ  Shi FH  Cai YM  Shen W  Taylor MG  Wu XF 《Parasite immunology》2004,26(8-9):351-358
A 600 bp DNA fragment was amplified by PCR from an adult Schistosoma japonicum cDNA library. Sequence analysis confirmed that this fragment contained an S. japonicum Chinese mainland strain fatty acid binding protein (Sj14FABP) gene. This gene was subsequently expressed in Escherichia coli (E. coli) and in Baculovirus/silkworm systems. The recombinant protein from E. coli was a 41 kDa GST fusion protein (rSj14/GST), which could be purified by glutathione agarose affinity chromatography, with a yield of 25 mg/L E. coli culture. The recombinant protein from the Baculovirus/silkworm system was an 18 kDa fusion protein (rSj14/His), which could be purified by Ni-NTA resin chromatography column with a yield of 3.5 mg per silkworm larva. Both rSj14/GST and rSj14/His could be recognized by S. japonicum-infected mouse sera and anti-rSj14/GST mouse sera in Western blotting. The purified recombinant protein was immunogenic in mice, rats and sheep, and 34.3%, 31.9% and 59.2% worm reductions, respectively, were obtained in vaccinated Kunming mice, Wistar rats and sheep vaccinated with Sj14/GST, compared to non-vaccinated control groups. Worm reductions of 48.8% and 49.0% were recorded in Balb/c mice immunized with Sj14/His, compared to non-vaccinated and BCG-vaccinated groups, respectively. These results indicate that rSj14FABP is a promising candidate vaccine for schistosomiasis japonica, particularly as in the rat and sheep vaccination experiments, no adjuvant was used.  相似文献   
950.
2019年12月以来,湖北省武汉市陆续发现了多例新型冠状病毒肺炎(COVID-19)患者,随着疫情在全国蔓延,全国各地积极采取疫情防控措施。为保障疫情期间药学工作顺利开展,进一步做好疫情期间“以患者为中心,科学防控”的药学服务,为临床一线医务人员提供有利支持,笔者基于新型冠状病毒的特点和药学日常工作的积累探索建立了药学服务模式策略,旨在为广大一线药学人员防控感染提供参考和帮助。  相似文献   
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