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101.
Tetraethylammonium (TEA) effects on K currents were examined on either side of the membrane of hippocampal CA1 neurons by means of whole-cell voltage-clamp recording and intracellular perfusion. Recording media contained ion channel blockers to allow the selective activation of voltage-dependent K currents which consisted of a rapidly decaying component (A-current) and a delayed component. Voltage protocols were applied to separate the A-current from the delayed component. Results show that 10 mM extracellular TEA suppressed 50 +/- 11% (S.D., n = 4) of the delayed current at different levels of depolarization but had little effect on the A-current. In contrast 10 mM TEA applied by intracellular perfusion suppressed the A-current by 42 +/- 10% (S.D., n = 4) in addition to inhibiting the delayed currently 55 +/- 15% (S.D., n = 4). Both the intracellular and extracellular actions of TEA on K currents showed no voltage- nor time-dependency. The results suggest that voltage-dependent transient current (A-current) is mediated through a separate group of ionic channels distinct from those that sustained the delayed current. Furthermore, the asymmetrical effects of intracellular and extracellular TEA on the transient current are similar to those described for the A-current in molluscan neurons. This observation supports the notion that the structure of the ion channel mediating the A-current is closely conserved across different species. 相似文献
102.
川芎嗪对脑外伤患者血栓素、前列腺环素及颅内压的影响 总被引:6,自引:0,他引:6
28例重度脑外伤患者分为川药嗪治疗组和一般治疗对照组,两组病人均于用药前和用药后3小时测定血浆和脑室内脑脊液(VCSF)中血栓素代谢产物(TXB_2)前列腺环素代谢产物6—酮—PGF_(la)(6KP)和颅内压。结果表明:两组治疗前血浆、VCSF中TXB_2及T/K均明显高于正常献血员对照组,川芎嗪能降低脑外伤患者血浆、VCSF中TXB_2及T/K值,对颅内压则无明显影响。提示川芎嗪能抑制脑外伤对血小板的激活、纠正循环血中TXA_2—PGI_2平衡失调,从而改善脑微循环。 相似文献
103.
本文通过对38例经手术证实为异位妊娠患者手术前所测血清β-HCG与正常宫内妊娠(早期)血清β-HCG动态变化进行回顾性分析,探讨异位妊娠血清β-HCG动态变化特点,并比较17例异位妊娠的腹腔内出血β-HCG与静脉血的β-HCG之间关系。结果表明异位妊娠血清β-HCG明显低于同期正常宫内妊娠,有极显著性差异(P<0.01);且其动态变化呈单峰曲线而正常同期妊娠仍持续上升。腹腔内出血β-HCG明显高于静脉血;这两种特点对早期诊断异位妊娠有重要临床意义。 相似文献
104.
By a double-labeling method combining the retrograde tracing of horseradish peroxidase and the immunocytochemical technique, serotonin-like immunoreactive neurons in the midbrain periaqueductal gray (PAG) and nucleus raphe dorsalis (DR) of the rat were observed to send projection fibers to the nucleus parafascicularis of the thalamus bilaterally with an ipsilateral dominance. These serotonin-containing projecting neurons were observed mainly at the middle-caudal levels of the ventrolateral subdivision of the PAG and less at the middle-rostral levels of the DR. 相似文献
105.
A case of duodenojejunal intussusception secondary to a large hamartomatous polyp of Brunner's glands was reported in a 15-year-old girl. Despite a great preponderance of ileocolic intussusception in childhood, this is the first reported case of duodenojejunal intussusception occurring in that age group. The diagnosis was not made by clinical examination; complete duodenal obstruction was shown in upper gastrointestinal series and by endoscopy. The intussusception was reduced manually at laparotomy, and the polyp was excised. Pathological examination revealed a preponderance of normal-appearing Brunner's glands in the tumor, consistent with the diagnosis of Brunner's gland hamartoma. 相似文献
106.
We treated 56 consecutive acute segmental femoral shaft fractures with closed static locked nailing. 12 nails were dynamized after 6 (5-10) months due to slow fracture healing and 5 united after another 5 (3-8) months. The other 7 required cancellous bone grafting and all healed uneventfully 6 (5-8) months after grafting. Since dynamization did not promote healing in most of our cases we suggest early cancellous bone grafting in cases of delayed union. 相似文献
107.
永瓣藤化学成分的研究 总被引:2,自引:1,他引:1
永瓣藤化学成分的研究陈玲,谢平,戚薇,曾菊珍(药学系中药化学教研室)关键词永瓣藤,化学成分,三萜,蒜盘子甾酮永瓣藤(MonimopetalnmChinenseRe-hd)系卫矛科永瓣藤属植物[1],为我国特有的珍稀二类保护植物[2],分布于江西东北部... 相似文献
108.
The therapeutic response and toxic effects of chemotherapy using several doses of doxorubicin in conventional solution form or bound to an ion-exchange resin were compared in a rat tumor model, to assess the relationship of drug dose to therapeutic efficacy and associated toxicity. Single bolus injections of 3.0, 4.5, 6.0, 7.5 and 9.0 mg/kg were administered via the abdominal aorta to rats bearing hindlimb tumors. Tumor size was measured serially and the growth rates of treated groups were compared with a control growth curve. In addition, the effect of empty microspheres on tumor growth rate was assessed. The levels of circulating white blood cells were measured and compared to control levels to provide an indication of the severity of bone marrow toxicity experienced by each form of treatment. Finally, any difference in the distribution of doxorubicin to tumor, hindlimb and cardiac tissue following administration of doxorubicin as free drug or on microspheres was ascertained. Empty ion-exchange resin exerted a small although significant detrimental effect on tumor growth which may be explained by the embolization of microspheres in the precapillary blood vessels of the tumor resulting in a transient delay in tumor growth rate. The lowest dose of doxorubicin produced a significantly better therapeutic response when administered in the free drug form, but higher doses elicited an equivalent delay in tumor growth for both drug microsphere and free drug groups in a dose-dependent manner, with the maximum anti-tumor response occurring at the highest dose. Treatment with free doxorubicin at high doses resulted in significant reductions of circulating white blood cells suggesting the occurrence of bone marrow toxicity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
109.
陈富 《中国媒介生物学及控制杂志》1992,3(2):114-116
本文对59名接触实验动物大白鼠引起23例流行性出血热(EHF)的流行病学和临床症状进行了调查,发病率为38.98%。发病的有副教授、讲师、助教、研究生等。发病多在春季,年龄组在21~40岁,男多于女。经间接免疫荧光技术检查,大白鼠肺EHFV抗原阳性率为32.69%。临床分型以中型为多,其次为重型和轻型。临床症状以发热、头痛、腰痛、全身痛、食欲不振、酒醉貌为主,没有死亡病例。血清间接免疫荧光抗体IgG在1:320~1:5 120之间的占91.30%。 相似文献
110.