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71.
咬肌与颅面形态的关系 总被引:3,自引:0,他引:3
目的探讨咬肌与颅面形态之间的关系,了解咬肌体积与邻近骨骼结构的大小及形态的相关性。方法对40例要求改变脸型者进行磁共振成像(MRI)测量,人体测量,头部正位、侧位和下颌骨曲面断层X线检查,测量并计算咬肌体积(MsV),测量头长(HL)、头宽(HB)、面长(FL)、面宽(FB)、下颌角间宽(IB)、下颌骨体长(CL)、下颌角切线长(MAL)、下颌角角度(JA),计算颜面形态指数FI(FL/FB)、头颅指数C(IHB/HL)。用SPSS11.5软件统计分析MsV与HI。HB、FL、FB、IB、CL、MAL、JA、FI、CI之间的相关性。结果MsV与JA呈明显负相关,与CL、MAL、IB、FB、HL呈明显正相关,与CL、FI、HB无明显相关性。结论咬肌肥大可能是方脸面型的成因之一,是影响面型的重要因素。 相似文献
72.
当归对衰老小鼠脑组织细胞凋亡及胸腺指数的影响 总被引:2,自引:0,他引:2
目的:研究当归的抗衰老作用及作用机制。方法:用D—半乳糖诱导小鼠制成衰老模型,同时给予不同剂量的当归水煎剂,观察当归对脑组织细胞凋亡及胸腺指数的影响。结果:当归能明显抑制小鼠脑组织细胞凋亡,提高胸腺指数。结论:当归具有抗衰老作用。 相似文献
73.
目的:研究特发性脊柱侧凸(IS)患者椎旁肌组织中神经营养素3(Neurotrophin-3,NT-3)在核酸水平(mRNA)的表达情况。方法:随机选择19例IS患者,年龄12~19岁,平均14.3岁,Cobb角42°~80°(平均54°)。手术中取顶椎(T7~T10)凸侧、凹侧椎旁肌肉组织,采用半定量RT-PCR法检测NT-3 mRNA表达水平。取4例相同年龄段的椎间盘突出患者手术切口头端非病变部位椎旁肌肉组织作为对照。结果:对照组椎旁肌中NT-3的mRNA表达阳性率50%,相对表达量为0.0237±0.0158,IS组患者椎旁肌中表达阳性率63.16%,相对表达量为0.1213±0.0939,较对照组表达量增加(P=0.051)。9例Cobb角>50°的IS患者表达阳性率为44.44%,相对表达量0.0431±0.0359,和对照组无明显差异;10例Cobb角≤50°的IS患者中表达阳性率为80%,相对表达量为0.1604±0.0895,与对照组和Cobb角>50°的IS患者比较有明显增加(P<0.01)。结论:正常椎旁肌组织中NT-3在核酸水平微量表达,特发性脊柱侧凸患者椎旁肌组织中NT-3 mRNA表达增加,尤其在小角度IS患者中增加明显,提示IS患者中存在神经营养因子表达异常。 相似文献
74.
目的:观察体外联合培养的成纤维细胞对平滑肌细胞形态和增殖的影响,为研究成纤维细胞和平滑肌细胞生物学特性和相互关系以及体外构建含此两种细胞的组织工程皮肤提供理论和实践基础。方法:在体外分别分离培养成纤维细胞和平滑肌细胞并常规传代培养。模拟组织工程皮肤的结构及成纤维细胞和平滑肌细胞间的相互影响途径,按照不同比例(平滑肌细胞:成纤维细胞=1:1,1:2,1:3)建立以胶原凝胶为基质的成纤维细胞与平滑肌细胞联合培养模型。应用荧光标记、组织学观察和MTT法对平滑肌细胞的形态和代谢进行研究。结果:联合培养模型法可以有效地建立起成纤维细胞和平滑肌细胞的相互影响模式。1:1组的成纤维细胞对联合培养的平滑肌细胞增殖有促进作用,1:3组的促增殖作用则不明显。结论:1:1联合培养的成纤维细胞对平滑肌细胞增殖有促进作用,对它们体外培养和扩增以及相互关系的研究对阐明这两种细胞组合作为真皮替代物种子细胞具有重要的意义。 相似文献
75.
Jean-Fran ois Marini Fran oise Pons Jocelyne Leger Nathalie Loffreda Monique Anoal Martine Chevallay Michel Fardeau Jean J. Leger 《Neuromuscular disorders : NMD》1991,1(6):397-409
The expression of MHC isoforms in the skeletal muscles of nine patients with Duchenne muscular dystrophy (DMD) (from 2.5 to 15 yr of age) and three DMD carriers was studied using different specific anti-MHC MAbs. We also analyzed muscle fiber size and fiber reactivity with acridine orange and/or with a surface antigen marker. One-quarter of all fibers of DMD patients, or less with age, were of normal size and contained only adult slow MHC. Half of the muscle fibers contained adult and developmental MHCs. Only half of these fibers were representative of an active regenerative process. MHC co-expression also altered the proportion of normal fast or slow fibers. Adult fast MHCs were expressed as unique MHC only in small and very small fibers in the oldest DMD patients. In DMD carrier muscles, the greatest alterations in MHC expression were observed in patients with the most reduced dystrophin expression. However, MHC changes in dystrophin-positive fibers were similar to those observed in dystrophin-free fibers. In conclusion, disruptions or delays in the switching of all genes coding for adult fast and slow MHC and developmental MHC coincided with dystrophin deletion and with perturbations in its expression. 相似文献
76.
自1999年1月-2005年3月,应用胫前肌瓣修复胫骨骨髓炎合并软组织缺损13例,同时辅以中药治疗,获得较满意的效果,现报告如下。1临床资料本组13例,男9例,女4例;年龄1867岁,平均32岁。致伤原因:车祸伤6例,挤压伤4例,烧伤1例,坠落伤2例。胫骨上1/3段1例,中1/3段2例,下1/3段5例,中下2/3段5例。病程12d30个月,外露骨有干燥、硬化、发白、变黑,周围有肉芽、瘢痕组织、脓性分泌物等。外露骨纵形长0·68·0cm,皮肤缺损面积最大为4cm×10cm。2治疗方法2·1手术方法在硬膜外麻醉下,股部上止血带,术区常规消毒。首先切除溃疡及外露胫骨周围瘢痕,清除髓腔内分泌物及 相似文献
77.
Facial muscle spasms, which are rare in adults, present a particularly difficult entity for the optometrist to recognise. The condition may not even manifest itself at an eye examination and the optometrist may have to rely on subjective symptoms to assist in the recognition of the condition. It is important to diagnose the condition correctly as specific and effective treatment is available. 相似文献
78.
HATIM A. OMAR M.D. LARRY A. RHODES M.D. ROLANDO RAMIREZ JELICA ARSICH M.D. STANLEY EINZIG M.D. Ph .D. 《Journal of cardiovascular electrophysiology》1996,7(12):1197-1203
Antiarrhythmic and Placental Vessels. Introduction : Antiarrhythmic medications are commonly used during pregnancy for treatment of maternal or fetal arrhythmias, but little is known about their effect on human placental vascular tone and, consequently, placental blood flow. The objective of this study was to evaluate the tone responses caused by antiarrhythmic medications in human placental vessels from normal term pregnancies in vitro.
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO2 35 to 38 torr) were exposed to cumulative doses of quinidine, procainamide, lidocaine, flecainide, propranolol, amiodarone, verapamil, digoxin, and adenosine after submaximal contraction with 5-hydroxytryptamine. The study was conducted both in the presence and absence of endothelium. The addition of the tested medications caused a significant, dose-dependent relaxation of human placental arteries and veins except for adenosine, which induced a sustained, dose-dependent contraction of human placental vessels regardless of the presence or absence of tone. Removal of the endothelium did not alter these responses.
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor. 相似文献
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor. 相似文献
79.
钙拮抗剂TMB-8抑制BHQ,NE和KCl引起的培养乳牛基底动脉单个平滑肌细胞内游离钙的升高 总被引:1,自引:0,他引:1
用AR CM MIC阳离子测定系统,测量单个细胞内游离钙浓度([Ca2+]i),研究8-(N,N-二乙胺)-n-辛基 3,4,5-三甲氧基苯甲酸酯(TMB-8)对培养乳牛基底动脉平滑肌[Ca2+]i的作用。在细胞外钙浓度为1.3mmol·L-1时,TMB-8(30μmol·L-1)可明显抑制BHQ,NE及KCl引起[Ca2+]i的升高。在细胞外钙为零+EGTA 0.1mmol·L-1时,TMB-8(10,30及100μmol·L-1)可浓度依赖性地降低静息[Ca2+]i,TMB-8(30μmol·L-1)可几乎完全阻断BHQ及NE引起[Ca2+]i的增加。研究表明TMB-8降低培养乳牛基底动脉平滑肌[Ca2+]i的机制,主要是抑制肌浆网Ca2+的释放,或增加肌浆网对Ca2+的摄入,并由此间接地抑制细胞外钙的内流。 相似文献
80.
Kenichiro Mikawa Hiroaki Kume Kenzo Takagi 《Clinical and experimental pharmacology & physiology》1997,24(2):175-181
1. In order to examine the mechanisms of cGMP-induced relaxation in airway smooth muscle, the effects of atrial natriuretic peptide (ANP) and 8-brom cGMP on muscle tone were studied by measuring isometric tension, while the effects on cytosolic Ca2+ concentrations were studied by measuring the spectra of fura-2 loaded in guinea-pig tracheal strips. 2. Atrial natriuretic peptide and 8-brom cGMP caused a concentration-dependent inhibition of spontaneous tone in the guinea-pig trachea. The relaxant effects of these agents on spontaneous tone were markedly suppressed in the presence of iberiotoxin (IbTX), a selective inhibitor of large-conductance Ca2+-activated K+ (BKca) channels. Iberiotoxin (30 nmol/L) markedly affected the maximal effect induced by ANP and 8-brom cGMP and augmented EC70 values for ANP and EC50values for 8-brom cGMP approximately 27- and 17-fold, respectively. The inhibitory effects of IbTX on relaxation induced by these agents were diminished in the presence of 1 μmol/L nifedipine, an antagonist of voltage-operated Ca2+channels (VOCC). 3. The inhibitory action of ANP and 8-brom cGMP on spontaneous tone was not affected by the presence of 10 μmol/L glibenclamide, an inhibitor of ATP-sensitive K+ channels, and 100 nmol/L apamin, an inhibitor of small-conductance Ca2+-activated K+ channels. When these agents were applied to tissues precontracted by high (40mmol/L) K+, the relaxant effects of these agents markedly diminished. 4. The extracellular Ca2+-dependent contraction was inhibited in the presence of 0.3 μmoI/L ANP or 0.1 mmol/L 8-brom cGMP. Concentration—response curves to extracellular Ca2+ (0.03—2.4 mmol/L) were markedly diminished by exposure to these agents. The maximal effect induced by extracellular Ca2+ was affected by these agents. 5. Atrial natriuretic peptide caused an inhibition of spontaneous tone accompanied by a reduction in the intracellular Ca2+ concentration. In the presence of IbTX, the elimination of both muscle tone and cytosolic Ca2+ by ANP was suppressed. 6. We conclude that ANP and 8-brom cGMP activate BKca channels and that the inhibition of Ca2+ influx through VOCC, mediated by BKca channel activation, may be involved in cGMP-dependent bronchodilation. 相似文献