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991.
上肢骨干天鹅型记忆接骨器的设计与临床应用 总被引:85,自引:10,他引:75
目的:研究应用于上肢骨干骨折与骨不连内固定的新型记忆合金接骨器。方法:利用镍钛合金与上肢骨干解剖生理的特性和特征,采用光弹,电测及三维有限元法研制天鹅型记忆接骨器(SMC),临床应用于锁骨、肱骨、尺桡骨干骨折与骨不连188例243根,平均随访2.25年。结果:SMC在轴向多点位抗剪、折、旋、持骨力98.40-125.05N;在纵向,将152-196N的记忆应力作用于骨断端。骨不连92例106例,平均术后3.8个月,不连处为类骨板样骨替代,骨折93例134根,平均术后2.6个月骨折处为骨板样愈合,全部病例无感染,无取出本器后再骨折和因本器所致的关节功能障碍,优良率98.76%,结论:SMC多点位轴向持骨,纵向加压、是治疗上肢骨干骨折与骨不连新而有效的技术与方法。 相似文献
992.
瘤体注射IL-2重组腺病毒基因治疗小鼠胶质母细胞瘤及其免疫机制的初步探讨 总被引:1,自引:0,他引:1
目的:观察瘤体直接注射IL-2重组腺病毒对G422皮下荷瘤的治疗作用,对体内基因转染效率及治疗的免疫机制进行初步分析。方法:将LacZ,IL-2重组腺病毒直接注射到皮下接种的G422胶质母细胞瘤瘤体,X-gal染色检测基因转染的效率,观察肿瘤的大小和荷瘤小鼠的存活期,采用4h^51Cr释放法检测荷瘤小鼠脾细胞诱导的NK、LAK、CTL的杀伤活性,对治疗后的肿瘤进行常规病理分析。结果:采用瘤体注射腺病毒具有较高的体内基因转染效率,瘤体注射IL-2重组腺病毒对皮下建立的胶质母细胞瘤有一定的治疗作用,肿瘤的生长受抑制,荷瘤小鼠的存活期显延长,但没有长期存活小鼠。IL-2基因治疗组小鼠脾细胞的LAK、CTL杀伤活性显增强,肿瘤局部出现更多的坏死和炎性浸润细胞。结论:采用瘤体直接注射IL-2重组腺病毒对胶质母细胞瘤皮下荷瘤有治疗,其机制可能是增强了宿主的局部和全身抗肿瘤免疫反应。 相似文献
993.
Association of angiotensin Ⅱ type 1 receptor gene polymorphism with essential hypertension 总被引:5,自引:1,他引:4
Objective To determine whether the polymorphism A1166C in the angiotensin Ⅱ type 1 receptor (AT1R) gene is associated with essential hypertension.Methods A case-control study was carried out using 125 hypertensive and 103 normotensive subjects. The A→C variant at position 1166 (A1166C) of t he AT1R gene was identified by polymerase chain reaction (PCR) and PCR/ restriction fragment length polymorphism (PCR/RFLP) analysis. The digestion products were separated on 2% agarose gels and visualized with ethid ium bromide under ultraviolet ray.Results The differences in C1166 allele frequency and in the AC genotype dist ribution of the AT1R gene between the hypertensive and normotensive groups were statistically significant (C allele: 0.092 vs 0.034, χ(2) =6.1 86, P<0.05; AC genotype: 0.184 vs 0.068, χ(2) =6.654, P<0.05).Conclusion The AC genotype is associated with essential hypertension, and the C a llele may be a marker for predisposition to hypertension in Chinese H an population. 相似文献
994.
听骨链CT仿真内窥镜的临床应用 总被引:3,自引:0,他引:3
目的 探讨听骨链CT仿真内窥镜 (CTVE)的临床应用价值及其限度。方法 使用准直 1 0mm、螺距 1 0扫描 ,骨算法、视野 9 6cm、间隔 0 1- 0 2mm重建对 4 0例临床怀疑中耳病变(30例手术 )的患者进行CTVE成像 ,并与轴位高分辨率CT(HRCT)、多平面重组 (MPR)图像及手术结果进行对照分析。结果 CTVE诊断听小骨破坏的准确性为 92 6% ,明显高于轴位HRCT(84 % )和MPR(77% )图像。CTVE也能清楚地显示听骨链发育异常和术后的状况。结论 CTVE能显示听骨链的立体影像 ,有利于听骨链病变的显示和诊断。但CTVE不能清楚地显示鼓室腔内异常软组织、鼓膜和鼓室骨壁的异常改变 ,且结果易受人为因素影响。 相似文献
995.
Percutaneous balloon angioplasty of coarctation of the aorta in children: 12 -year follow-up results 总被引:5,自引:0,他引:5
Objective To evaluate the efficiency of percutaneous balloon angioplasty of coarctation o f the aorta in children and discuss its risk factors that can lead to poor long -term results.Methods From September 1987 to August 1999, 24 patients underwent 27 balloon angioplasty procedures for native or recurrent coarctation of the aorta at our institution . There were 19 patients with discrete (membranous) coarctation, 4 patients wit h long-segment and aortic arch hypoplasia, and 1 patient with postoperative recu rr ence. The balloon diameter was chosen not to exceed the diameter of the aorta p roximal to the stenotic site (11.06±2.80 mm vs 11.78±3.18 mm), with th e chosen diameter two to four times that of the stenotic segment (2.57±0.68 t imes). The patients have been followed up for half to twelve years (mean 6.2 ±2.8 years). Satisfactory result was defined as a reduction in the pressure g radient across the site of coarctation to ≤20 mm Hg. Results The systolic pressure gradient across the coarctation site decreased from 48. 17±14.68 mm Hg to 14.96±13.12 mm Hg (P<0.01) and the diameter of the coarctation site increased from 4.66±2.43 mm to 8.80±3.32 mm (P<0. 01). Immediate satisfactory results were obtained in 19 patients (79%). Of the 5 patients with unsatisfactory results, 4 had aortic arch hypoplasia and 1 had membranous coarctation. Of the 19 patients with satisfactory results, 18 patie nts had membranous coarctation and 1 patient had recurrent postoperative coarcta tion. No aneurysm and other complications had occurred in any patients at the follow-ups. Conclusion Percutaneous balloon angioplasty is an effective treatment alternative to surger y in most patients with recurrent postoperative or native membranous coarctation of the aorta. It should not be recommended for the coarctation of aortic arch hypoplasia. 相似文献
996.
The role of sexual related Y gene detection in the diagnosis of patients with gonadal dysgenesis 总被引:5,自引:0,他引:5
Objective To clarify the role of sexual related Y (SRY) gene detection in the diagnosis of gonadal dysgenesis.Methods Sixteen cases of gonadal dysgenesis were included in this study: 5 with androgen insensitivity syndrome, 1 with 17-α-hydroxylase deficiency, 4 with true herm aphrodite, 2 with 45,X/46,XY gonadal dysgenesis, 1 with 45,X gonadal dysgenesis, 1 with XY pure gonadal dysgenesis, 1 with testicular regression, and 1 XY fema le who gave birth to a normal baby. SRY gene was detected by using polymerase c hain reaction (PCR) in blood and gonad samples and by direct sequencing of the S RY motif. Results Among the 16 cases, 15 were blood SRY positive, among which 13 (86.7%) showed t he presence of testicular tissue, and 2 showed ovaries without testicular tissue . One SRY negative case showed the presence of testicular tissue. In 3 cases, SRY detection in gonadal tissue correlated with pathological findings but not wi th blood karyotype. The correlation between peripheral blood SRY and the pathol ogy of the gonads was 81.25% and the correlation between the presence of periph eral blood Y chromosome and pathology of the gonads was 68.75%. Sequencing of the SRY motif in an XY female who gave birth to a normal baby showed no mutatio n.Conclusions SRY detection is more sensitive and specific than blood karyotype in the predic tion of the presence of testicular tissue. Peripheral blood karyotype does not necessarily reflect gonadal type. There may be testicular related factors other than the SRY gene. 相似文献
997.
Objective To assess the effect of the balloon valvuloplasty for congenital valvular aortic stenosis (AS) in children.Methods A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV).The ratios of balloon/valve were 0.95±0.08 for 19 cases of typical AS and 1.00±0.11 for 8 cases of hyp oplastic AS.The patients were evaluated by the gradients across aotic valves i n pre- and post-PBAV and by echocardiogram during the follow-up period.Results Fifteen of 19 (78.9%)cases of typical AS had a better outcome and the gradien t of the remaining 4 cases (26.7%) had increased after follow-up (ΔP>50 mm Hg).Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose.There was no moderate to s evere aortic insufficiency (AI). Conclusion The balloon aortic valvuloplasty provides safe and significant hemodynamic and c linical improvement in pediatric patients.The outcome of PBAV for typical AS is better than for hypoplastic AS. 相似文献
998.
小儿肝移植无肝期丙泊酚的药代动力学特点 总被引:6,自引:0,他引:6
目的:研究小儿肝移植无肝期丙泊酚的药代动力学特征。方法:5例同种异体原位肝移植患,分别于麻醉诱导及无肝期开始时静脉注射丙泊酚2mg/kg,采用反相高效液相色谱法测定血浆中丙泊酚浓度,对比两之间的药代动力学差异。结果:丙泊酚的药-时曲线符合开放性三室模型,具有分布广,清除率高等特性。结论:无肝期与诱导期丙泊酚代谢无明显差异,推测该药可能存在明显的肝外代谢。 相似文献
999.
目的:通过质子磁共振波谱(^1H MRS)研究外伤性中脑损伤早期异部异常代谢状态及其与预后的关系。方法:在伤后早期,应用^1H MRS技术分别对19例中脑损伤及10例正常对照中脑腹侧区域的代谢变化进行研究,测定胆碱(Cho)、总肌酸(Cr)、N-乙酰天冬氨酸(NAA)、Cho/Cr,Cr/NAA,Cho/NAA等指标,分别分析中脑损伤时谱变化及与Glassgow预后评分(GOS)间的相关关系,同时研究持续昏迷时间不同患间波谱变化的不同。结果:中脑损伤组Cho,Cr,Cho.Cr及Cho/NAA明显下降;NAA,Cr/NAA及Cho/NAA与GOS间存在直线相关关系;昏迷长于30d患局部Cho,Cho/Cr,Cho/NAA值明显低于昏迷短于30d患。结论:损伤局部与Cho,Cr能反映中脑损伤的情况;NAA有助于判断患预后;中脑Cho,Cho/Cr,Cho/NAA下降程度与昏迷时间长短一致。 相似文献
1000.
Arsenic trioxide induces multiple myeloma cell apoptosis viadisruption of mitochondrial transmembrane potentials and activation of caspase-3 总被引:17,自引:1,他引:16
Objective To investigate the response of multiple myeloma (MM) cells to arsenic trioxide (As2O3 ) and their possible mechanisms. Methods Two MM-derived cell lines RPMI8226 and U266 cells were used as in vitro models. Cell apoptosis was assessed by morphology, flow cytometry, and DNA gel electrophoresis. Mitochondrial transmembrane potentials (△Ψm) were evaluated by measuring cellular Rhodamine 123 staining intensity. Protein expression was analyzed using Western blot. Results Zero point one to 0.5μmol/L As2O3 inhibited cell proliferation and 2.0?μmol/L As2O3 induced cell apoptosis, while 1.0μmol/L As2O3 inhibited proliferation with a weak degree of apoptosis induction in RPMI8226 and U266 cell lines. As2O3-induced apoptosis was accompanied by mitochondrial transmembrane potentials (△Ψm) collapse and caspase-3 activation in the presence of intact membrane. Glutathione depleter buthionine sulfoximine enhanced, while disulfide bond-reducing agent dithiothreitol partially antagonized As2O3 -induced △Ψm collapse and apoptosis in MM cells. All-trans retinoic acid (ATRA) could also induce apoptosis in RPMI8226 cells, but it did not show any cooperative effects with As2O3. Conclusion As2O3 exerts apoptosis-inducing and growth-inhibiting effects on MM cells, and mitochondrium is a pivotal and common target of As2O3 for apoptosis induction. 相似文献