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981.
磷酸钙骨水泥修复良性骨肿瘤骨缺损   总被引:1,自引:0,他引:1  
目的:研究磷酸钙骨水泥(CPC)修复良性骨肿瘤刮除术后遗留的骨缺损的临床应用。方法:应用CPC修复33例患者良性骨肿瘤刮除术后遗留的骨缺损。患者平均年龄38岁,肿瘤类型依次为骨纤维结构不良、骨巨细胞瘤、骨囊肿、动脉瘤样骨囊肿、软骨粘液样纤维瘤、非骨化性纤维瘤、骨母细胞瘤,观察患者术中CPC固化时间,术后全身及切口局部反应,血钙、磷值变化,X线片和CT扫描,平均随访时间19个月。结果:全部患者未见明显不良反应,血钙、磷值未见升高,X线片显示骨缺损处均填充良好,随访见所有患者均有CPC降解和骨替代现象发生。结论:良性骨肿瘤刮除后利用CPC填充修复骨缺损,可充分填充骨肿瘤刮除后不规则瘤腔,即刻恢复骨的强度.经骨替代后可真正完成骨修复。术式简单.并发症少。  相似文献   
982.
目的:探讨胃复春片治疗慢性胃病患者前后生长抑素内分泌细胞(D细胞)数量变化。方法:用免疫组化酶链亲合素过氧化酶复合技术(SABC)对患者治疗前后胃粘膜组织的D细胞染色,观察治疗前后D细胞的形态和数量变化。结果:经胃复春片治疗后,患者胃窦粘膜D细胞阳性数及强阳性率均明显下降,有显著意义。结论:胃复春片对慢性胃病患者生长抑素D细胞有调整作用。  相似文献   
983.
本文报告—缺指(趾)综合征之家族。在4代62人中手足畸形者20人,对3代7人拍照了双手足正位X线片,发现足部2-4跖趾均缺如,1、5跖趾呈现跖外翻,趾内曲。外形酷似龙虾爪样。手部1-3指大多数病人缺如。也有2、3指并指畸形或指骨分叉畸形。全身其他骨关节正常,智力发育良好。本文讨论了该病的命名、分类和有关鉴别诊断。  相似文献   
984.
The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y1-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y1-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y1receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y1receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y1-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y1-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals.  相似文献   
985.
将胚鼠中脑腹侧组织制成细胞悬液移植于帕金森病(PD)模型鼠侧脑室,动态观察受体鼠在移植前后的行为变化。移植后16周应用诱发荧光及免疫细胞化学等方法,对移植物在受体鼠脑内的存活及生长情况进行了研究。结果,受体鼠旋转行为明显改善,侧脑室内可见黄绿色荧光细胞及酪氨酸羟化酶(TH)免疫反应阳性细胞,有的发出突起伸向室管膜及迁于尾核区.提示:移植的胚鼠黑质细胞生长良好,似作为触液神经元发挥其作用。  相似文献   
986.
阿魏酸在血瘀证兔体内的药代动力学   总被引:2,自引:0,他引:2  
为验证及研究症治药动学假说(syndromeandTreatmentPharmacokinetics,S&TPK)的客观性和基本规律,本文以RP-HPLC法同时测定了活血祛瘀药物阿魏酸在正常及高分子右旋糖酐所制血瘀症(微循环障碍)兔体内经时浓度,以MCPKP药动学程序在COMPAQ80386机上自动拟合了药动学参数。统计结果表明,与正常组相比,阿魏酸在血瘀症兔体内的分布容积(V_1和V_B)及消除速率(CLB)显著减小(P<0.05),半衰期(t_(1/2β)及相同时间段曲线下面积(AUQ)非常显著增加(P<0.01)。结论:实验结果基本符合S&TPK的观点:即同一药物在不同证兔体内的药代动力学参数经统计学处理有显著差异。  相似文献   
987.
We report the case of a patient with delayed methotrexate (MTX)-induced leukoencephalopathy who showed a marked improvement both in clinical and neuroimaging findings after a high-dose of the active form of folinic acid (leucovorin) treatment. The patient developed progressive affective impairment accompanied by headache, nausea and vomiting after treatment with MTX during the chemotherapy for acute lymphoblastic leukemia, and diagnosed as delayed type MTX-induced leukoencephalopathy. After an intravenous injection of high-dose folinic acid (total 1920 mg), neurological deficits and white matter changes dramatically improved in a few weeks. Although delayed MTX-induced leukoencephalopathy may cause irreversible brain damage, an early treatment with high dose leucovorin may thus facilitate the marked improvement of clinical findings and white matter abnormalities.  相似文献   
988.
林树新  李剑 《医学争鸣》1998,19(6):661-664
观察亮氨酸脑啡肽和脂多糖对血平滑肌细胞增殖的影响,并观察两者之间的相互作用及阿片受体阻滞剂纳洛酮的影响,方法:实验以离体培养的SD大鼠胸主动脉VSMC为模型。  相似文献   
989.
The effects of 10% dietary xylitol supplementation in ovariectomized rats were studied on the degradation of bone organic and inorganic structures. The osseal concentrations of hydroxyproline, pyridinoline, and deoxypyridinoline were analyzed by high-performance liquid chromatography. Bone resorption was measured in [3H]tetracycline-prelabeled rats by urinary excretion of 3H, and by the amount of 3H preserved in bone. Bone trabeculation was measured by a computer image analyzer from sections stained by the method of von Kossa. The amount of collagen in bone organic fraction was lower in ovariectomized rats as compared with the sham-operated controls. This most likely is partly a consequence of an increased resorption, and partly a consequence of a higher proportion of immature periosteal bone in the ovariectomized animals, leading to a higher ratio of noncollagenous protein to collagen. The number of pyridinium crosslinks was lower in proportion, indicating no selective changes in the structure of collagen. Dietary xylitol significantly retarded the ovariectomy-associated decrease in the relative amount of collagen and the number of its mature crosslinks. Ovariectomy doubled the excretion of 3H and caused a significant decrease in the amount of 3H preserved in bone; both these changes were significantly retarded by the 10% dietary xylitol supplementation. Ovariectomy significantly decreased the volume of bone trabeculae, but this effect was also significantly inhibited by the xylitol supplementation in the diet. In conclusion, these findings suggest a dietary xylitol-induced normalizing effect on the rate of bone turnover in ovariectomized rats. Received: 12 February 1996 / Accepted: 20 August 1996  相似文献   
990.
Gradient acoustic noise has been measured and characterized for an epoxy-potted, shielded gradient assembly in a 1.5 T MRI system. Noise levels vary by 10 dB or more as a function of longitudinal position in the scanner and reflect the pattern of forces applied to the gradient assembly. The noise level increases slightly (1–3 dB) with a patient in the scanner. The spectrum of the noise is similar (but not identical) to the spectrum of the input signal. A gradient-pulse-to-acoustic-noise transfer function was obtained by using a white noise voltage input to the gradient system. The transfer function enabled us to accurately predict acoustic noise output for a pulse sequence consisting of a series of trapezoidal pulses on a single axis and for a clinical fast spin echo sequence with gradients present on all three axes.  相似文献   
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