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21.
Calcified tissue is a common component of atherosclerotic plaques, and occurs most often in mature plaques. The process of calcification is a poorly understood risk factor that may contribute to a plaque's vulnerability to sudden rupture. In this study a solid-state imaging sequence, termed single-point imaging (SPI), was used to observe calcification directly in ex vivo atherosclerotic plaques. Standards were used to validate the ability of (31)P SPI to detect and differentiate calcification from crystalline cholesterol, phospholipids, and other plaque components. After suitable experimental parameters were found, human carotid specimens obtained by endarterectomy were imaged ex vivo by (31)P solid-state imaging and standard (1)H methods. In contrast to (1)H imaging methods, (31)P imaging detected only the calcification in the plaque. 相似文献
22.
高压氧综合治疗持续植物状态30例疗效分析 总被引:14,自引:0,他引:14
目的评估高压氧综合治疗持续植物状态的疗效和探讨最佳治疗方案。方法回顾性分析了1999年—2005年应用高压氧治疗的30例持续植物状态病例,主要分析了原发病因、高压氧治疗次数以及高压氧治疗时机与疗效的关系。结果脑外伤组显效率和好转率明显高于非脑外伤组(P<0.05),开始治疗时间≤30d组及31~60d组好转率明显高于≥61d组(P<0.05)。结论高压氧综合治疗对脑外伤所致持续植物状态患者60d以内开始行高压氧治疗的患者疗效较好。 相似文献
23.
慢性肺心病哮喘持续状态218例临床分析 总被引:1,自引:0,他引:1
目的探索治疗慢性肺心病哮喘持续状态的方法。方法回顾性分析1983年10月~2005年3月收治的218例慢性肺心病哮喘持续状态患者的临床资料。结果哮喘持续状态在48h以内被控制的62例(28.4%);在72h以内控制的56例(25.7%);在120h以内控制的25例(11.5%);在168h以内控制的34例(15.6%);痊愈出院177例(81.2%);死亡41例(18.8%)。结论(1)治疗慢性肺心病哮喘持续状态.根据患者的病理变化.综合治疗.效果显著。(2)在治疗过程中.要恰当选择抗生素和平喘药;对那些血液黏滞度增高的患者.要加用血液稀释疗法。(3)测定血液黏滞度和氧饱和度.可以指导治疗、估计预后.应当列为常规检查。 相似文献
24.
T. Akatsu T. Murakami K. Ono M. Nishikawa E. Tsuda S.-I. Mochizuki N. Fujise K. Higashio K. Motoyoshi M. Yamamoto N. Nagata 《BONE》1998,23(6):495-498
Osteoclastogenesis inhibitory factor (OCIF) is a novel secreted protein that inhibits osteoclastogenesis both in vitro and in vivo. In this study, we examined the effects of OCIF on serum calcium (Ca) concentrations in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy. In normal mice, a single intraperitoneal injection of OCIF reduced serum Ca levels in a dose-dependent manner. Significant decrease in serum Ca (by 1.6 ± 0.3 mg/dL, n = 5) was observed 2 h after the injection of OCIF at 20 mg/kg and the hypocalcemic effect continued for up to 12 h. Serum phosphate (Pi) concentrations also decreased in response to OCIF. Urinary excretion of Ca, Pi, and creatinine did not change significantly after injection of OCIF or vehicle. In hypercalcemic, tumor-bearing nude mice, a single intraperitoneal injection of OCIF at 20 mg/kg resulted in a dramatic decrease in serum Ca (maximal decrease 2.8 ± 0.37 mg/dL, n = 11), which continued for up to 24 h. The results suggest that OCIF decreased serum Ca through its inhibitory effect on bone resorption. Furthermore, it is suggested that OCIF has therapeutic potential for the treatment of hypercalcemic conditions such as malignancy-associated hypercalcemia. 相似文献
25.
目的:为设计维甲酸治疗神经母细胞瘤可能的有效方案,本文对9-顺式维甲酸(9-cis retinoic acid,9-cisRA)体外诱导分化神经母细胞瘤细胞(SK-N-SH)作用进行了研究。方法:SK-N-SH细胞经9-cisRA处理后,采用相差显微镜,神经纤维银染法,透射电镜观察等手段。观察9-cisRA对细胞生长的影响。结果:9-cisRA作用SK-N-SH细胞7d后,细胞形态发生变化;12d时出现神经原性表型,多个细胞形成“神经节”,节间形成粗而长的类神经纤维;尼氏小体和银染法亦证明细胞产生显著分化,透射电镜观察结果表明,9-cisRA对该细胞有分化作用。却无明显凋亡诱导作用。结论:9-cisRA对神经母细胞瘤细胞体外能产生明显诱导分化作用。 相似文献
26.
A case of an uncommon congenital primitive neuroectodermal cerebellar tumor (PNET) in a 5-month-old child is reported. After subtotal surgical resection, the residual tumor did not respond to radiation and chemotherapy. Histologically, the tumor was composed of small, round, undifferentiated cells and several other patterns like astrocytomatous, oligodendrogliomatous, and ependymomatous structures. Immunostaining was positive for most of the cells for vimentin and S 100, fewer were positive for glial fibrillary acid protein (GFAP) and neuron-specific enolase, and only a few for synaptophysin. Surprisingly, the tumor showed strong expression of several monoclonal cytokeratins (CK) with different molecular weights, together with epithelial membrane antigen. Furthermore, we found a coexpression of the tumor cells for CK and vimentin, while CK-GFAP and CK-S 100 were negative. Ultrastructurally, intracyto-plasmic intermediate filaments could be observed corresponding to immunohistochemical CK expression. The very strong CK and vimentin expression in this case was interpreted as a sign of the embryonic nature of the tumor. 相似文献
27.
Balanced steady-state free precession (bSSFP) has become increasingly important in clinical applications. Its signal properties have been investigated over several years by many groups, and various critical factors for bSSFP signal intensity and stability, such as off-resonances, flow, and eddy currents, have been identified. It is generally accepted that bSSFP signal intensity is a function of relaxation times, excitation angles, and spin densities only. While this is true for simple phantoms, it appears that signals from tissues are significantly less intense than predicted by theory. This work demonstrates that the molecular origin of this apparent signal reduction is due to on-resonance magnetization transfer (MT). High flip angles in combination with very short repetition times (TRs), as commonly used for bSSFP, lead to a considerable saturation in the fraction of macromolecular (MM) pool protons. As a result, bSSFP signal is strongly attenuated by up to a factor of 2 in the human brain compared to the signal expected from theory. 相似文献
28.
A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images. 相似文献
29.
100例性病患者心理健康状况调查分析 总被引:3,自引:1,他引:2
目的:探讨性病患者的心理健康状况,为临床治疗和护理提供依据。方法:采用症状自评量表(SCL-90)对100例性病患者的心理健康状况进行测验。结果:100例性病患者SCL-90检测的阳性率为51%,阳性样本因子分居前的是敌对、强迫症状、抑郁、人际敏感。结论:性病患者广泛存在的心理问题,在药用治疗的同时应注意心理方面的治疗和疏导。 相似文献
30.
李松林副主任医师将肾小球肾炎的病机概括为湿、热、毒、瘀、虚等方面,在中医辨证的基础上,结合现代医学对其病因和发病机理的认识及中草药药理作用,针对不同的病理机制和临床表现,提出清热解毒法,活血化瘀法,调补脾肾法,扶正固本法,并视症有机结合,恰当治疗,疗效显著。 相似文献