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排序方式: 共有637条查询结果,搜索用时 156 毫秒
1.
I. Y. Shvera A. M. Cherniavsky W. Yu. Ussov M. P. Plotnikov A. A. Sokolov V. M. Shipulin V. I. Chernov 《European journal of nuclear medicine and molecular imaging》1995,22(2):132-138
In this study we aimed to work out a quantitative prognostic index for preoperative assessment of brain technetium-99m hexamethylpropylene amine oxime (HMPAO) single-photon emission tomography (SPET) in patients referred for urgent carotid endarterectomy due to acute obstructive disease of the internal carotid artery (ICA) and neurological deficit. To this end we compared data from preoperative SPET studies with the postinterventional changes in neurological status in 20 patients (17 males, three females; mean age 53 years, SD 4 years) with acute ischaemic cerebral disorders induced by obstruction of the ICA. Carotid obstruction was diagnosed by ultrasound B-mode study. All patients underwent urgent carotid endarterectomy from the ICA. Patients were divided into two groups in accordance with the results of postoperative follow-up: group A comprised patients with significant (more than 3 points) postoperative improvement in neurological condition as quantified by the Canadian Neurological Scale (11 patients); group B consisted of patients with minimal improvement or deterioration (nine, three of whom died). All patients were studied preoperatively by99mTc-HMPAO SPET. The volume of nonperfused tissue (VS, cm3) was quantified using the Mountz technique. Hypoperfused volume (V
hypoperf, cm3) in the affected hemisphere was calculated as the total volume of voxels with99mTc-HMPAO uptake <90% of the contralateral symmetric voxels. Discriminant prognostic function was calculated by discriminant analysis as:PF = 0.072×VS + 29.46×(VS/V
hypoperf). Patients with preoperativePF values <8.20 demonstrated postoperative improvement in neurological status, while the group withPF>8.90 comprised patients who demonstrated minimal improvement or deterioration. PF values in the range 8.20–8.90 carried an indefinite prognosis. We conclude that the preoperative99mTc-HMPAO SPET can be used for the selection of patients in whom improvement in neurological status may be expected after urgent surgical correction of acute extracranial obstruction of the ICA. 相似文献
2.
目的:对中国药典收载的头孢噻肟钠聚合物测定条件进行改进。 方法 :采用高效液相色谱法 ,以Sephadex G- 10色谱柱 4 2 cm× 1.3cm对 6批样品进行分析 ,分别进样 5 0μl和 2 0 0μl,按外标法计算聚合物的量。结果:头孢噻肟钠在 10~ 6 0 μg/m l范围内线性关系良好 (r=0 .9995 ) ,高中低浓度的加样回收率分别为 10 0 .2 %、10 0 .4 %、99.7% ;RSD分别为 1.7%、1.5 %、1.9% (n =3)。该方法与药典方法比较 ,差异无统计学意义 (P >0 .0 5 )。 结论:本方法简便、快速、可行 ,具有实用价值 相似文献
3.
Kazim M. Yazici Özlem Kapucu Belkis Erbas Erhan Varoglu Cengiz Gülec Coskun F. Bekdik 《European journal of nuclear medicine and molecular imaging》1992,19(12):1038-1043
Regional cerebral blood flow was investigated in 14 patients with major depression diagnosed according to the DSM-III-R criteria (six patients with single and eight patients with recurrent episodes) and in ten healthy volunteers. The mean ages of the patients and the controls were 33.5 ± 2.7 and 31.6 ± 2.6 years, respectively. The severity of the depression was assessed using the 17-item Hamilton Depression Scale (mean: 23.2 ± 1.5). None of the patients was under medication. After administration of 500 MBq technetium-99m hexamethylpropylene amine oxime, a single photon emission tomography study was performed and then transaxial, sagittal and coronal slices were obtained. For the semiquantitative analysis of the data, the ratios of the mean counts/pixel to the whole slice were calculated for 24 regions on three consecutive transaxial slices in the orbitomeatal plane. Additionally, left/right and frontal/occipital ratios were calculated. Both sides of the temporal region had a significantly decreased cerebral blood flow (CBF) when compared to the controls. The left/right ratio of the prefrontal region was also significantly lower in the patients than in the controls. The Hamilton score had a negative correlation with blood flow in the anterofrontal and left prefrontal regions. According to our results, regional CBF seems to be decreased in the left prefrontal and in both temporal regions in major depression. The severity of depression is correlated with the reduction in CBF in the regions of the anterofrontal and left prefrontal cortex. 相似文献
4.
优立新与头孢噻肟随机对照治疗呼吸道和泌尿道感染40例,临床有效率各为100%和95%(P>0.05),细菌阴转率各为94,1%和100%(P>0.05)。无显著性差异。优立新共治疗30例,临床有效率和细菌阴转率分别为100%和96%。两药副反应均轻微。无因副反应而停药。在优立新治疗病例中,有2例出现皮疹。另2例为肝功能ALT和AST暂时性轻度增高。 相似文献
5.
炔诺酮肟对大鼠抗着床抗早孕作用机理的形态学研究 总被引:1,自引:0,他引:1
大鼠从妊娠第一天开始每日灌服炔诺酮肟4mg/kg,共3天。结果能引起早孕大鼠黄体细胞滑面内质网减少;脂滴大量积贮;抑制卵巢3β-羟基甾体脱氢酶活性,从而使卵巢孕酮生物合成受阻。药物还能引起早孕大鼠子宫蜕膜的病理改变,蜕膜细胞出现变性,坏死,宫腔内大量出血,白细胞浸润,胚胎发育不良,蜕膜细胞内糖原及碱性磷酸酶含量均下降。本文还讨论了药物引起卵巢孕酮生物合成受阻与蜕膜变化的关系。 相似文献
6.
D. S. C. Marshall N. R. Newberry P. J. Ryan 《European journal of nuclear medicine and molecular imaging》1996,23(12):1634-1635
There are no published data for the activity of technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) found 1in breast milk. The amount of radioactivity in breast milk following the administration of 500 MBq99mTc-HMPAO for a brain perfusion study has been measured. The effective dose to the infant was calculated to be 0.26 mSv, so necessitating no interruption of breast feeding. Unbound99mTc is readily secreted into breast milk and the effective dose will remain less than 1 mSv if the99mTc-HMPAO labelling effici ency is 99% for the worse reported case, and could remain <1 mSv for the mean reported case for99mTc-HMPAO labelling efficiencies down to 94%. 相似文献
7.
红霉素A肟的新合成方法 总被引:9,自引:6,他引:9
目的 用一种全新的方法合成红霉素A肟(1)。方法 在酸碱缓冲溶液中由红霉素A(3)与盐酸羟胺缩合生成1。系统研究了反应体系的pH值、反应温度以及盐酸羟胺的加入量对反应结果的影响。同时对红霉素A肟化反应机理进行了推导。结果 红霉素A9—肟的收率达95%以上,产品纯度达92%。化合物1经红外、氢谱、碳谱、质谱鉴定,与文献报道相一致。结论 该方法有效地抑制了红霉素A的酸性分解,与文献方法相比,大幅度提高了反应的收率和产品的纯度。 相似文献
8.
阿奇霉素治疗细菌性感染的临床疗效 总被引:2,自引:0,他引:2
目的:评价注射用阿奇霉素治疗细菌性感染的有效性及安全性。方法:60例呼吸系统和泌尿系统细菌感染性疾病患者随机分为治疗组和对照组,每组30例,治疗组静滴阿奇霉素250 mg,qd,疗程5 d。对照组静滴头孢噻肟钠2 g,qd,疗程7d。结果:治疗组与对照组治疗细菌感染性疾病的有效率分别为90.0%与80.0%,两组比较无统计学差异(P>0.05);细菌清除率分别为89.3%与62.1%,两组比较有统计学差异(P<0.05);不良反应发生率均为6.7%。结论:注射用阿奇霉素治疗细菌性感染疗效高、安全性好。 相似文献
9.
羧甲基壳聚糖银、锌、铈的合成及抑菌实验的研究 总被引:3,自引:0,他引:3
报道了羧甲基壳聚糖银、锌、铈的合成及其混合物对金黄色葡萄球菌、铜绿假单孢菌、大肠埃希氏菌、肺炎克雷伯氏菌和变形杆菌的抑菌作用 ,并与磺胺嘧啶银进行比较 ,结果发现 ,羧甲基壳聚糖银、锌、铈水溶液 (含量为 0 .6 95mg/ml,Ag、Zn、Ce含量分别为 0 .2 5 2× 10 6、5 .2 8× 10 6、2 .15 4× 10 6)对上述 5种细菌 (含量为10 4CFU/ml)杀菌率为 96 %以上 ,与 1.0mg/ml磺胺嘧啶银作用相当 相似文献
10.