骨骼肌卫星细胞纯化及培养的实验研究

目的:建立一种骨骼肌卫星细胞纯化及培养方法。方法:取成年雌性SD大鼠前肢肱三头肌,用胶原酶和Dispase进行消化,采用差速贴壁的方法纯化骨骼肌卫星细胞,用含20%胎牛血清的Hams-F10培养基进行培养,α-骨骼肌肌动蛋白(α-sarcometricactin)免疫细胞化学染色进行细胞鉴定。结果:成功地分离培养了成年大白鼠的骨骼肌卫星细胞。结论:采用差速贴壁的方法可以成功纯化骨骼肌卫星细胞,为将来自体肌卫星细胞移植治疗压力性尿失禁打下了基础。     

大鼠肌源性干细胞的分离、纯化和培养

背景:要获得满足临床需要的肌源性干细胞,体外筛选和扩增已成为关键环节.目的:拟建立稳定高效的成年大鼠肌源性干细胞的分离培养、纯化方法.方法:成年SD大鼠麻醉后,无菌条件下取骨骼肌,采用Ⅺ型胶原酶、Dispase和胰酶消化法获得肌源性干细胞,以密度梯度离心法和差速贴壁法进行纯化.记录细胞生长曲线,MTT比色法观察不同接种密度对细胞生长的影响,采用免疫细胞化学染色对细胞进行鉴定.结果与结论:原代肌源性干细胞体积较小,贴壁缓慢,折光性较好,多呈球形、梭形或纺锤形,增殖缓慢.传代培养后,加入含体积分数为20%血清浓度的完全培养基,以1×109L-1密度接种时活细胞数量最多,为适宜接种密度,传1～4代细胞生长状态良好.免疫细胞化学染色结果为desmin(+),CD34(+),CD45(-),Sea-1(+),证实通过体外原代培养获得了高纯度的肌源性干细胞,并成功扩增.     

差速贴壁法体外培养失神经骨骼肌肌源性干细胞的生物学特性

目的:探讨失神经过程中的肌源性干细胞的生物学特性,掌握其分离、培养及鉴定方法,了解其生长规律并进行体内定位。方法:实验于2004-01/2005-10华中科技大学同济医学院附属协和医院手外科完成。选取清洁级3周龄昆明种小鼠5只,切断小鼠双侧坐骨神经,造成失神经损伤模型。采用XI型胶原酶和胰蛋白酶消化法及差速贴壁法分离细胞获取小鼠肌源性干细胞,进行体外原代和传代培养。观察细胞的形态,通过生长曲线分析肌源性干细胞的增殖能力,利用免疫细胞化学染色对所获得的细胞进行鉴定。结果:①失神经骨骼肌内肌源性干细胞生长特性:失神经骨骼肌肌源性干细胞原代培养时细胞贴壁及生长较慢,1个月后才进行传代。传代培养3d后部分细胞呈梭形,成簇状生长。7～10d后大部分为梭形和多形状,细胞间相互出现成片融合,此后细胞生长速度放慢。②失神经骨骼肌肌源性干细胞生长曲线的绘制:细胞培养前3d细胞生长慢,3d后生长明显加快,7d后生长明显放慢,进入平台期。③失神经骨骼肌内肌源性干细胞的表型鉴定:细胞质CD34和Sca-1染色均呈阳性,细胞核大。④失神经骨骼肌内肌源性干细胞的体内定位:CD34和Sca-1阳性细胞位于肌细胞和基底膜之间,细胞小,细胞数量较少。结论:采用差速贴壁法可从失神经骨骼肌内分离出肌源性干细胞,体外培养的肌源性干细胞具有良好的增殖能力,适用于组织工程和基因治疗。     

差速贴壁法体外培养失神经骨骼肌肌源性干细胞的生物学特性

目的：探讨失神经过程中的肌源性干细胞的生物学特性，掌握其分离、培养及鉴定方法，了解其生长规律并进行体内定位。 方法：实验于2004-01／2005—10华中科技大学同济医学院附属协和医院手外科完成。选取清洁级3周龄昆明种小鼠5只，切断小鼠双侧坐骨神经．造成失神经损伤模型。采用Ⅺ型胶原酶和胰蛋白酶消化法及差速贴壁法分离细胞获取小鼠肌源性干细胞，进行体外原代和传代培养。观察细胞的形态，通过生长曲线分析肌源性干细胞的增殖能力，利用免疫细胞化学染色对所获得的细胞进行鉴定。 结果：①失神经骨骼肌内肌源性干细胞生长特性：失神经骨骼肌肌源性干细胞原代培养时细胞贴壁及生长较慢，1个月后才进行传代。传代培养3d后部分细胞呈梭形，成簇状生长。7-10d后大部分为梭形和多形状，细胞间相互出现成片融合，此后细胞生长速度放慢。②失神经骨骼肌肌源性干细胞生长曲线的绘制：细胞培养前3d细胞生长慢，3d后生长明显加快．7d后生长明显放慢，进入平台期。③失神经骨骼肌内肌源性干细胞的表型鉴定：细胞质CD34和Sca-1染色均呈阳性，细胞核大。④失神经骨骼肌内肌源性干细胞的体内定位：CD34和Sea-1阳性细胞位于肌细胞和基底膜之间，细胞小，细胞数量较少。 结论：采用差速贴壁法可从失神经骨骼肌内分离出肌源性干细胞，体外培养的肌源性干细胞具有良好的增殖能力，适用于组织工程和基因治疗。     

大鼠肌源性干细胞的培养与鉴定

背景:肌源性干细胞是一种成体多能干细胞,已成为基因治疗和细胞介导的组织工程领域内的研究热点,临床应用自体肌源性干细胞注射治疗压力性尿失禁具有广泛前景。目的:探讨大鼠肌源性干细胞体外原代培养的方法,为临床应用自体肌源性干细胞注射治疗压力性尿失禁提供实验依据。设计:重复观察测量。单位:武汉大学人民医院生殖中心与泌尿外科。材料:实验于2003-12/2004-05在武汉大学人民医院泌尿外科实验室完成。选取4～6周龄雌性SD大鼠20只,XI型胶原酶、胰酶、多聚赖氨酸(Sigma公司),dispase酶(Gibco公司),鸡胚提取液(自制)。方法:①将大鼠以质量浓度为10g/L的戊巴比妥钠30g/kg腹腔麻醉后,无菌条件下取腓肠肌,置入冷DMEM培养基中,D-Hank’s液洗涤组织块,除去筋膜、肌腱、神经和血管,剪成1.0～3.0mm3小块,移入离心管。向组织中加入0.2%XI型胶原酶及0.1%的胰酶,采用胶原酶分离大鼠骨骼肌细胞。②应用差速贴壁法大鼠骨骼肌细胞进行纯化。细胞筛网过滤后接种至多聚赖氨酸包被的培养瓶中,37℃、体积分数为0.05的CO2培养箱中孵育1h,未贴壁细胞移入新的培养瓶中,加入新的培养基37℃培养1h后,未贴壁细胞再次转瓶换液,37℃培养过夜,如此反复,每次间隔24h转瓶换液,培养第5～6天贴壁的细胞即肌源性干细胞。③细胞生长到70%融合后,胰蛋白酶消化,以1∶2的比例进行传代。传代细胞消化后接种于放有盖玻片的6孔培养板中,加入生长培养基,24h后制备细胞爬片,采用免疫组织化学方法鉴定所培养细胞上特异性结蛋白抗原和干细胞抗原-1的表达。主要观察指标:肌源性干细胞的形态及其鉴定结果。结果:①肌源性干细胞的形态观察:从骨骼肌组织中分离出来的肌源性干细胞呈球形,折光性强。培养12h后开始贴壁仍为圆形,48h后贴壁完全并开始增生,细胞逐渐延展成梭形或纺锤形,有两极,体积小。随培养时间的延长,细胞相互融合形成成熟的多核肌管。②肌源性干细胞的鉴定结果:细胞特异性结蛋白抗原和干细胞抗原-1染色呈阳性,荧光显微镜可见细胞浆发出红色荧光,阳性率达90%。结论:肌原性干细胞属于成体干细胞,具有取材方便、免疫原性低、移植后存活时间长等优点。高纯度的肌原性干细胞可通过体外原代培养获取,免疫组化技术可鉴定其肌源性和干细胞特性,在组织工程和基因治疗中具有广泛的应用前景。     

以差速贴壁与化学药物并胰酶限时消化法纯化新生大鼠嗅鞘细胞:优于单一差速贴壁和化学药物法吗?

背景:目前国内外对嗅鞘细胞培养条件的报道各不相同,个别方法重复性较差,不利于实际应用.目的:观察差速贴壁+化学药物+胰酶限时消化法纯化大鼠嗅鞘细胞的效果,并与化学药物法、差速贴壁法培养结果进行比较.设计、时间及地点:细胞学体外对照观察,于2007-06/2008-06在福建医科大学人体解剖与组织胚胎学系实验室完成.材料:新生2 d的SD大鼠8只,由福建医科大学试验动物中心提供.方法:无菌条件下完整取出大鼠双侧嗅球,剥除嗅球表面的软脑膜及毛细血管网,剪成0.5 mm~3的小块进行胰蛋白酶消化,过筛后按4.0×10~8L~(-1)密度种植于包被多聚左旋赖氨酸的培养瓶中进行原代培养.设立4组:①未经纯化的常规对照组.②化学药物组加入5 μmol/L阿糖胞苷抑制成纤维细胞分裂.③差速贴壁组采用Nash差速贴壁法纯化嗅鞘细胞.④差速贴壁+化学药物+胰酶限时消化组首先采用Nash差速贴壁法去除大部分成纤维细胞,而后对于少量残留的成纤维细胞加入阿糖胞苷处理,培养6 d贴壁细胞大部分融合后,加入1.25 g/L胰蛋白酶消化1 min,显微镜下见突起回缩、细胞变圆、少量细胞浮起时终止消化.主要观察指标:嗅鞘细胞的形态,NGFR p75免疫细胞荧光染色结果.结果:体外培养的新生大鼠嗅球嗅鞘细胞主要为双极或三极细胞,其突起细长;未经纯化的常规对照组培养7 d时视野内成纤维细胞已达60%以上,至14 d成纤维细胞完全长满;经过纯化处理的另外3组始终以嗅鞘细胞居多,嗅鞘细胞的形态与原代基本相同.存活的双极和3极嗅鞘细胞呈NGFRp75阳性反应,但化学药物组、差速贴壁组嗅鞘细胞纯度偏低,仅为75%:差速贴壁+化学药物+胰酶限时消化组嗅鞘细胞纯化效率明显增高,达85%以上.结论:实验结果证实了差速贴壁+化学药物+胰酶限时消化法的三合一操作技术,是一种高效率的纯化培养嗅球嗅鞘细胞的方法.     

单次差速贴壁法纯化培养大鼠嗅神经鞘细胞的实验研究

目的:探讨单次差速贴壁法纯化培养成年大鼠嗅球嗅鞘细胞的可行性.方法:选取8～10周龄的成年SD大鼠,无菌条件下切取嗅球、剪碎,胰酶消化制成细胞悬液后接种,采用18 h单次差速贴壁的方法纯化培养嗅鞘细胞,定期在倒置显微镜下观察嗅鞘细胞的形态学变化及生长情况,并对其行神经生长因子受体p75抗体(NGFR p75)及碘化丙啶的免疫荧光鉴定,同时计算嗅鞘细胞的纯度.结果:通过18 h单次差速贴壁法纯化培养的嗅鞘细胞经NGFR p75免疫荧光鉴定后,纯度可达70%～80%,形态上以双极和三极细胞为主,伴有少许单极及多极细胞.结论:应用18 h单次差速贴壁法纯化培养嗅鞘细胞是一种简便、稳定、经济、快捷的方法.     

改良Nash差速贴壁联合阿糖胞苷法体外分离培养大鼠嗅球及嗅黏膜源性嗅鞘细胞

背景:目前常用的嗅鞘细胞培养方法有差速贴壁法、化学抑制法、抗体亲和吸附法、补体法等,各自均存在优缺点,单一使用某种方法时细胞纯化率较低.目的:拟采用改良Nash差速贴壁+阿糖胞苷法体外分离纯化大鼠嗅球及嗅黏膜来源的嗅鞘细胞.设计、时间及地点:细胞学体外对照观察.于2007-11/2008-05在武汉大学人民医院骨科实验室和消化内科实验室完成.材料:10周龄Sprague-Dauley大鼠10只,由武汉大学人民医院实验动物中心提供,阿糖胞苷由武汉大学人民医院制备.方法:完整取大鼠双侧嗅球及剪取鼻中隔后1/3嗅黏膜,剪碎后胰酶消化,制成单细胞悬液,按1×109L-1密度接种于末包被的25 cm2玻璃培养瓶中,18～20 h后将细胞悬液转移至另一未包被的25 cm2玻璃培养瓶中(第1次差速贴壁),24 h后再将细胞悬液转移至经多聚右旋赖氨酸包被的25 cm2塑料培养瓶或经多聚右旋赖氨酸包被的6孔培养板中(第2次差速贴壁),接种培养48 h后半量换液以去除杂细胞.在差速贴壁培养后二三天,加入3.0～5.0 pmol/L阿糖胞苷去除残余成纤维细胞.主要观察指标:嗅鞘细胞的形态观察、分裂增殖情况、免疫荧光染色鉴定结果及纯度测定.结果:体外培养24 h嗅球源性嗅鞘细胞即可贴壁,而嗅黏膜源性嗅鞘细胞多在培养四五天后贴壁,两种来源的嗅鞘细胞形态相似,以双极或梭形细胞为主,少量为3极及多突起形多级细胞,同时夹杂扁平、煎鸡蛋形细胞.纯化培养10 d的嗅鞘细胞,胶质纤维酸性蛋白、神经生长因子受体p75免疫荧光染色及神经生长因子受体p75+hoechs免疫荧光双染后大部分双极或多极细胞膜、胞体、突起呈阳性,细胞纯度可达90%以上.结论:改良Nash差速贴壁+阿糖胞苷法可在体外成功分离培养出高纯度的嗅球及嗅黏膜源性嗅鞘细胞,嗅球源性嗅鞘细胞贴壁时间及分裂增殖程度优于嗅黏膜源性嗅鞘细胞.     

大鼠肌源性干细胞的培养与鉴定

背景：肌源性干细胞是一种成体多能干细胞，已成为基因治疗和细胞介导的组织工程领域内的研究热点，临床应用自体肌源性干细胞注射治疗压力性尿失禁具有广泛前景。目的：探讨大鼠肌源性干细胞体外原代培养的方法，为临床应用自体肌源性干细胞注射治疗压力性尿失禁提供实验依据。设计：重复观察测量。单位：武汉大学人民医院生殖中心与泌尿外科。材料：实验于2003-12／2004-05在武汉大学人民医院泌尿外科实验室完成。选取4～6周龄雌性SD大鼠20只，XI型胶原酶、胰酶、多聚赖氨酸（Sigma公司），dispase酶（Gibco公司），鸡胚提取液（自制）。方法：①将大鼠以质量浓度为10异／L的戊巴比妥钠30s／ks腹腔麻醉后，无菌条件下取腓肠肌，置人冷DMEM培养基中，D—Hank’s液洗涤组织块，除去筋膜、肌腱、神经和血管。剪成1．0-3．0mm^3小块，移入离心管。向组织中加入0．2％XI型胶原酶及0．1％的胰酶。采用胶原酶分离大鼠骨骼肌细胞。②应用差速贴壁法大鼠骨骼肌细胞进行纯化。细胞筛网过滤后接种至多聚赖氨酸包被的培养瓶中，37℃、体积分数为0．05的CO2培养箱中孵育1h，未贴壁细胞移人新的培养瓶中，加入新的培养基37℃培养1h后，未贴壁细胞再次转瓶换液，37℃培养过夜，如此反复，每次间隔24h转瓶换液，培养第5-6天贴壁的细胞即肌源性干细胞。③细胞生长到70％融合后，胰蛋白酶消化，以1：2的比例进行传代。传代细胞消化后接种于放有盖玻片的6孔培养板中，加入生长培养基，24h后制备细胞爬片，采用免疫组织化学方法鉴定所培养细胞上特异性结蛋白抗原和干细胞抗原-1的表达。主要观察指标：肌源性干细胞的形态及其鉴定结果。结果：①肌源性干细胞的形态观察：从骨骼肌组织中分离出来的肌源性干细胞呈球形，折光性强。培养12h后开始贴壁仍为圆形，48h后贴壁完全并开始增生，细胞逐渐延展成梭形或纺锤形，有两极，体积小。随培养时间的延长，细胞相互融合形成成熟的多核肌管。②肌源性干细胞的鉴定结果：细胞特异性结蛋白抗原和干细胞抗原-1染色呈阳性，荧光显微镜可见细胞浆发出红色荧光。阳性率达90％。结论：肌原性干细胞属于成体干细胞，具有取材方便、免疫原性低、移植后存活时间长等优点O高纯度的肌原性干细胞可通过体外原代培养获取．免疫组化技术可鉴定其肌源性和干细胞特性，在组织工程和基因治疗中具有广泛的应用前景。     

原代培养差速贴壁法分离纯化大鼠腰椎间盘髓核细胞

背景：髓核细胞在体外培养过程中存在表型丢失问题,包括Ⅱ型胶原、aggrecan、Sox-9等表达的下降,由类软骨细胞向类纤维样细胞转化。目的：体外原代培养差速贴壁法分离纯化大鼠腰椎间盘髓核细胞。方法：经胰蛋白酶、Ⅱ型胶原酶先后消化Wistar大鼠椎间盘髓核组织,第1,2代细胞传代时采用差速贴壁法分离纯化髓核细胞。结果与结论：分离纯化后的第3代髓核细胞呈圆形或多角形,活力强,苏木精-伊红染色细胞核染成均一蓝黑色,胞浆呈现淡粉色;Ⅱ型胶原免疫组织化学染色阳性细胞比例为97%;aggrecan免疫组织化学染色阳性细胞比例为95%;扫描电镜可见细胞内有高尔基体、粗面内质网和游离核糖体,未见线粒体,可见少量板层小体;CCK-8生长曲线显示细胞经过2d的生长潜伏期,3d的指数生长期,进入生长停滞期。说明原代培养、两次差速贴壁法分离纯化的大鼠髓核细胞代谢旺盛、表型一致。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.