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11.
培养Wistar大鼠乳鼠的心室肌细胞,向培养基中分别加入浓度为1.56μg/ml至50μg/ml的大豆皂甙,可使心肌细胞群落的自发性搏动呈剂量依赖性抑制。洗脱大豆皂甙或向培养基中再加入10μg/ml肾上腺素均能使自发性搏动恢复。向培养基中加入大豆皂甙5μg/ml使心肌细胞动作电位的波幅、波宽、超射、最大舒张电位、阈电位、最大除极速度等各电参数立即减小。Ca~(2+)80μg/ml能使动作电位的抑制逆转。上述结果表明大豆皂甙对培养的鼠心肌细胞具有钙通道阻滞用。 相似文献
12.
Neuronal adrenergic and muscular cholinergic contractile hypersensitivity in canine jejunum after extrinsic denervation 总被引:1,自引:1,他引:0
Bruno M. Balsiger M.D. Chong-Liang He M.D. Nicholas J. Zyromski M.D. Michael G. Sarr M.D. 《Journal of gastrointestinal surgery》2003,7(4):572-582
Extrinsic denervation may be responsible for motor dysfunction after small bowel transplantation. The aim of this study was
to examine the role of extrinsic innervation of canine jejunum on contractile activity. An in vitro dose response of cholinergic
and adrenergic agonists was evaluated in canine jejunal strips of circular muscle at 0, 2, and 8 weeks in a control group
and after jejunoileal extrinsic denervation (EX DEN). Neurons in circular muscle were quantitated by means of immunohistochemical
techniques. Adrenergic and cholinergic responses did not differ at any time in the control group. However, at 2 and 8 weeks,
extrinsic denervation caused an increased sensitivity to the procontractile effects of the cholinergic agonist bethanechol
at the level of the smooth muscle cells, and increased sensitivity to the inhibitory effects of the adrenergic agent norepinephrine
mediated at the level of the enteric nervous system. Immunohistochemical analysis showed a reduction in all neurons and a
complete lack of adrenergic fibers in the EX DEN group after 2 and 8 weeks. Extrinsic denervation induces enteric neuronal
cholinergic and adrenergic smooth muscle hypersensitivity in canine jejunal circular muscle.
Presented in part at the annual meeting of the American Gastroenterological Association, Orlando, Florida, May 18, 1999 (poster
presentation), and published as an abstract in Gastroenterology 116:A1075, 1999.
Supported by United States Public Health Service grant DK39337 from the National Institutes of Health (M.G.S.); the Swiss
National Science Foundation; the Swiss Society of Gastroenterology and Hepatology; the Swiss Foundation for Medical and Biological
Science; the Novartis Foundation; Astra Zeneca Pharmaceuticals, Switzerland; and the Department of Visceral and Transplantation
Surgery, University of Bern, Switzerland. 相似文献
13.
子宫角妊娠13例临床分析 总被引:4,自引:3,他引:1
目的:探讨子宫角妊娠的早期诊断,以提高对该病的认识和警惕,减少临床误诊率。方法:回顾性分析我院10年间收治的13例子宫角妊娠,总结其临床表现、诊断、处理。结果:子宫角妊娠占同期异位妊娠的1.35%,术前确诊率约30.7%,易误诊为宫内妊娠、输卵管妊娠。结论:认为血β-HCG、B超、腹腔镜检查对本病的早期诊断有重要意义,避免了如子宫破裂、大出血、胎盘滞留等严重并发症。 相似文献
14.
经阴道与经腹子宫肌瘤剔除术的比较 总被引:11,自引:3,他引:8
目的探讨经阴道子宫肌瘤剔除术的可行性、安全性及临床疗效.方法对92例子宫肌瘤分别施行经阴道肌瘤剔除术(研究组,n=46)及开腹肌瘤剔除术(对照组,n=46),并对两种术式的临床疗效进行比较.结果经阴道与经腹肌瘤剔除术均获成功.手术时间研究组与对照组比较差异无显著性(t=-0.734, P=0.465);平均术中出血量、术后肛门排气时间、术后疼痛、术后病率、住院日期研究组与对照组比较差异均有显著性.结论经阴道子宫肌瘤剔除术具有创伤小、术中出血少、术后肛门排气早、疼痛轻、术后病率低及住院时间短的优点,是一种安全可行的微创手术方式.但须正确掌握适应证. 相似文献
15.
腹腔镜用于子宫切除是一种微创手术 ,具有创伤小 ,痛苦轻 ,恢复快等特点。我院 2 0 0 1年开始施行腹腔镜子宫切除术 ,通过对 5 6例标准鞘内 SEMM式子宫切除术病人的护理 ,我们总结出围手术期护理对策。现将做法介绍如下。1 临床资料我院妇科 2 0 0 1至 2 0 0 2年腹腔镜子宫切除术患者 5 6例 ,子宫肌瘤 4 7例 ,功能性子宫出血 9例。年龄 38~ 5 3岁 ,平均年龄 4 4岁。手术方式全部为标准腹腔镜子宫筋膜内 SEMM式子宫切除术 (CISH)。麻醉方式全行吸入全身麻醉。手术时间 90~ 15 0 min。住院天数 9~ 15 d。术后住院天数 6~ 14 d。平均… 相似文献
16.
To determine if and how clonidine and tricyclic antidepressants affect gastric contractility. Guinea pig fundic and antral circular muscle strips were studied in vitro. The effects of clonidine or amitriptyline added in graded concentrations on contractions to electric field stimulation (EFS), acetylcholine (ACh), and SP in the presence of N(epsilon)-nitro-l-arginine methyl ester (l-NAME) were studied. EFS produced frequency dependent contractions of fundic and antral muscle that were abolished by atropine or tetrodotoxin (TTX). ACh contractions were abolished by atropine but not TTX. Clonidine reduced contractile response to EFS but had no effect on ACh contractions. The threshold concentration of clonidine to inhibit EFS contractions was lower in the fundus than in the antrum. Amitriptyline reduced contractions to both EFS and ACh but not to SP. The threshold concentration of amitriptyline to inhibit EFS contractions was lower in the antrum than in the fundus. Both clonidine and amitriptyline affect gastric contractility. At threshold concentrations, clonidine affects fundic contractility whereas amitriptyline affects antral contractility. Clonidine affects gastric contractility in response to EFS but not to ACh, suggesting alpha-2 receptors on cholinergic nerves that reduce ACh release. Amitriptyline inhibits gastric contractility to EFS and ACh suggesting an inhibitory muscle effect. 相似文献
17.
IUD对子宫收缩的影响观察 总被引:6,自引:3,他引:3
本文重点研究妇女正常月经净后七天之内子宫收缩压力和频率,以及频脱器妇女与第一次置器妇女子宫收缩压及其相互间的差别。结果:(1)23例妇女月经净后七天之内子宫收缩压力为2.21~14.14mmHg/次,均值7.66±2.89mmHg/次。10分钟内子宫收缩28~76次,均值4.51±1.14次/分;(2)第一次置器妇女与频脱器妇女其置器前、后子宫收缩压力大小无显著差异(P>0.05)(3)子宫腔内有器子宫收缩压力比子宫腔内无器时大。两组子宫收缩压力t 检验结果(P<0.05)有显著差异:(4)第一次置(取)器前、后当时子宫收缩压力及频率大小皆有显著差异(P<0.05)。置(取)器后子宫收缩压力比置(取)器前大;(5)频脱组在置器前、后当时子宫收缩压力大小有显著差异(P<0.05),与第一次置器组相同;(6)本法测试子宫收缩压力达37~62mmHg/次时,部分受术者即有明显的下腹痛或痛感较强。 相似文献
18.
A single-purpose analogue-computing device is described for the online assessment of the contractile state of the human myocardium from the left ventricular pressure (Plv) data available during routine cardiac catheterisation. Due attention has been paid to the design of the computer circuits so that they will not process pressure phenomena outside the isovolumic contractile period. Either a \(\left( {\frac{1}{{P_{lv} }}\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) or a plain \(\left( {\frac{{dP_{lv} }}{{dt}}} \right)_{max} \) index is presented on a digitalvoltmeter display, thus obviating the need for any graphical extrapolation or additional computation. 相似文献
19.
20.
Optimizing the embryo transfer technique 总被引:7,自引:0,他引:7
The technique of embryo transfer is very crucial and great attention and time should be given to this step. In order to optimize the embryo transfer technique, several precautions should be taken. The first and most important is to avoid the initiation of uterine contractility. This can be achieved by the use of soft catheters, gentle manipulation and by avoiding touching the fundus. Secondly, proper evaluation of the uterine cavity and utero-cervical angulation is very important, and can be achieved by performing dummy embryo transfer and by ultrasound evaluation of the utero-cervical angulation and uterine cavity length. Another important step is the removal of cervical mucus so that it does not stick to the catheter and inadvertently remove the embryo during catheter withdrawal. Finally, one has to be absolutely sure that the embryo transfer catheter has passed the internal cervical os and that the embryos are delivered gently inside the uterine cavity. 相似文献