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121.
122.
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
123.
124.
本研究以豚鼠皮层听觉诱发电位反应阈为指标,采用自体或群体对照方法,观察0.1Hz极低频磁场对豚鼠听力的影响。结果表明,豚鼠经50mT(毫特)、4h,100mT、48h及10mT、4周暴露后,听阈降低;50mT、48h,20mT、4周暴露后听阈无明显变化。提示0.1Hz极低频磁场对豚鼠听敏度无不利的影响,在某些暴露条件下,听敏度尚有改善。 相似文献
125.
E. García-Ojeda J.R. Alonso R. Arvalo J.G. Brin J. Lara J. Aijon 《Brain research bulletin》1992,29(6):783-793
The distributions of calbindin D-28K (CaBP) and parvalbumin (PV) in the rat nucleus olfactorius anterior (NOA) were described using monoclonal antibodies and the avidin-biotin-peroxidase method. The NOA showed a high immunoreactivity for CaBP, with a rostrocaudal increase in the positive neurons and fibres. Pars externa (NOAe) was the only subdivision which showed a low CaBP immunostaining. PV-positive elements were less abundant than those CaBP immunostained. The main difference in the distributions for both proteins was observed in the pars medialis which was practically PV negative. PV- and CaBP-stained neurons showed similar morphologies in the subdivisions where they were present. In NOAe, we observed a characteristic PV- and CaBP-positive neuronal type, with an oriented dendritic pattern. Transition areas were clearly observable in both CaBP- and PV-labelled sections. 相似文献
126.
目的研究不同月龄的雄性大鼠成骨细胞内钙浓度及钙通道电流是否存在差异.方法采用二次酶消化法分离不同月龄(分别为1、2、3、5、7、9、11、13、15)雄性大鼠的原代成骨细胞,通过激光扫描共聚焦技术测定细胞内游离钙浓度([Ca2+]i)(以平均荧光强度表示),同时应用全细胞膜片钳技术记录成骨细胞膜钙电流(ICa)的变化.结果共聚焦结果显示随月龄增加,成骨细胞内[Ca2+]i逐渐降低,但相邻2月龄组之间细胞内[Ca2+]i无显著性差异(P>0.05);1、2、3月龄组与11、13、15月龄组成骨细胞内[Ca2+]i有显著性差异(P<0.05),5、7、9月龄组与各组相比均无差异(P>0.05).应用全细胞膜片钳技术发现刺激电压为+10 mV时,2、7、13月龄组鼠ICa分别为(-392.77±97.07)pA、(-330.33±33.86)pA和(-287.68±71.01)pA,13月龄组鼠与2月龄组鼠相比,ICa明显降低(P<0.05),而7月龄组鼠与2月龄组鼠和13月龄组鼠相比,ICa均没有明显差异(P>0.05).结论不同月龄大鼠成骨细胞内[Ca2+]i存在差异,其机制可能与细胞膜上钙通道活性改变相关. 相似文献
127.
目的 研究联合补充大豆异黄酮和钙对去卵巢大鼠骨质疏松的预防作用。方法 将50只3月龄SD雌性大鼠摘除卵巢后按体重随机分成5组:假手术对照组、手术对照组、大豆异黄酮组(40mg/kgBW)、钙组(100mg/kgBW)、钙+大豆异黄酮组(Ca100mg/kgBW+SI40mg/kgBW)。连续灌胃饲养3个月后测定大鼠血清骨钙素,左侧股骨测定骨密度和骨钙含量、右侧股骨进行骨组织形态学计量分析。结果 Ca+SI组血清BGP水平和股骨骨密度均高于其他去卵巢各组(P〈0.05),但低于Sham组(P〈0.05);Ca+SI组大鼠股骨的骨钙含量与Ca组、Sham组差异均无统计学意义;在去卵巢各组大鼠中手术对照组、大豆异黄酮组和钙组大鼠的骨小梁数目和骨小梁厚度显著减少,骨小梁间距明显增宽,与钙+大豆异黄酮组相比有显著差异(P〈0.05)。结论 与单独补充大豆异黄酮或钙相比,大豆异黄酮与钙的联合应用能够更有效地预防去卵巢大鼠骨质疏松的发生。 相似文献
128.
A large number of neurotransmitters have now been shown to reduce the amplitude and slow the activation kinetics of whole cell HVA ICa in a great diversity of neurons. These transmitters include l-glutamate (AMPA/kainate, metabotropic and NMDA receptors), G AB A (via GABAB receptors, NA (via α2 receptors), 5-HT, N A (via α2 receptors), DA and several peptides. Both whole-cell and single-channel studies have demonstrated that the N-channel is the most common channel type to be blocked by transmitters, although an inhibition of the L-type channel has also occasionally been reported. The suppression of the N-type Ca current was commonly shown to be voltage-dependent, with a relief at large positive voltages. Strong evidence has been put forward showing that the transmitter action is mediated by a G-protein, with GDP-β-S blocking transmitter action, and GTP-γ-S directly inhibiting the Ca channel. Moreover, pertussis toxin blocked the transmitter action in most neurons, and following such block, injection of the G-protein G0 restored transmitter action. A direct link between the G-protein and the Ca channel has been widely theorized to mediate the action of transmitters on certain neurons. There is also some evidence that certain transmitters in specific neurons mediate calcium channel inhibition through a 2nd messenger, perhaps protein kinase C.Transmitters have also been found, although uncommonly, to inhibit HVA L-type and LVA T-type channels. In addition, an enhancement of both HVA and LVA, Ca currents by transmitters has been demonstrated, and substantial evidence exists for mediation of this action by cAMP. 相似文献
129.
选择62例拔除第一双尖牙的样本,分为平弓丝组、带“U”型阻滞曲组、固定舌弓组,采用方丝弓细丝弓技术,以磨牙作支抗拉尖牙向远中移动,对支抗磨牙进行观察。为期4周的观察发现,平弓丝组、带“U”型阻滞曲组的支抗磨牙均有近中舌向扭转,第二双尖牙中央窝间距亦比治疗前减少;而固定舌弓组支抗磨牙未见有近中舌向扭转。作者认为:以磨牙为支抗移动尖牙时,应注意支抗控制。本文对力的使用及支抗失控的预防、处理问题进行了讨论。 相似文献
130.
D. Agnusdei G. Crepaldi G. Isaia G. Mazzuoli S. Ortolani M. Passeri L. Bufalino C. Gennari 《Calcified tissue international》1997,61(2):142-147
One hundred ninety-eight postmenopausal women (aged 50–65 years) with vertebral bone density (VBD) 1 SD below the mean value
for normal, age-matched, postmenopausal subjects were enrolled in six Italian centers and 134 completed 2 years of treatment.
All subjects were randomly allocated to a 2-year treatment with oral ipriflavone (200 mg t.i.d.) or a matching placebo, according
to a double-blind, parallel group design. All patients also received an oral daily calcium supplement of 1 g as calcium carbonate.
VBD and markers of bone turnover were measured at baseline, and every 6 months. A complete routine analysis of liver and kidney
functions along with hematological parameters were measured before and at the end of treatment period. The valid completers
analysis showed a significant increase of VBD in ipriflavone-treated women with average percent changes of +1.4 after 1 year,
and +1% at the end of treatment period (P < 0.05). The placebo group presented a significant decrease of VBD after 2 years of treatment (P < 0.05). The difference between treatments was significant (P < 0.01). The intention to treat analysis confirmed the significant decrease of VBD in the placebo group, with no changes
in ipriflavone-treated women. Skeletal ALP significantly decreased in ipriflavone-treated women (P < 0.05). Serum BGP and urine HOP/Cr showed a significant decrease only in ipriflavone-treated women, suggesting an inhibitory
effect on bone turnover rate. Adverse reactions, mainly gastrointestinal, occurred to a similar extent in the two treatment
groups. The evaluation of patients' compliance, assessed by residual tablets count, revealed a drug intake of more than 80%
after 2 years in 92.5% and 92.8% of patients treated with ipriflavone or placebo, respectively. This study demonstrates that
ipriflavone can prevent bone loss in postmenopausal women with low bone mass.
Received: 1 April 1996 / Accepted: 5 March 1997 相似文献