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91.
三袖套管法大鼠肺移植 总被引:12,自引:2,他引:10
我们将血管套接技术用于大鼠肺移植中。在肉眼下,完成肺动静脉及支气管的吻合。在连续6例手术中,手术平均时间61±4分钟,移植物总缺血时间17±3分钟,手术时间缩短至国外同类手术的1/4,缺血时间缩短至同类手术的1/3。同时手术成功率达到75%(6/8),手术后生存率100%。行对侧肺切除术后,血气分析正常,显示了移植肺良好的气体交换功能 相似文献
92.
本文采用酸性洒料比色法测定甲氧异腈冻干品的含量。结果表明,使用溴甲酚紫1.5ml,PH值为6.0的磷酸盐缓冲液5ml,氯仿5ml提取,经振摇2min,静置15min为较理想比色条件,显色液稳定,甲氧异腈浓度在4-20μg/ml范围内与吸收度呈良好线性关系。 相似文献
93.
94.
单用全反式维甲酸(RA)诱导治疗急性早幼粒细胞白血病(APL)20例,完全缓解率达90%,诱导天数短(中位数为32d)。治疗过程中未发生DIC,亦无因强烈化疗引起骨髓抑制后造成的感染和出血的危险。该药的副反应轻,患者均能耐受。该组的中位生存期已达630d,可望长期存活。 相似文献
95.
96.
Pan X 《Medical physics》2000,27(9):2031-2036
The hybrid algorithms developed recently for the reconstruction of fan-beam images possess computational and noise properties superior to those of the fan-beam filtered backprojection (FFBP) algorithm. However, the hybrid algorithms cannot be applied directly to a halfscan fan-beam sinogram because they require knowledge of a fullscan fan-beam sinogram. In this work, we developed halfscan-hybrid algorithms for image reconstruction in halfscan computed tomography (CT). Numerical evaluation indicates that the proposed halfscan-hybrid algorithms are computationally more efficient than are the widely used halfscan-FFBP algorithms. Also, the results of quantitative studies demonstrated clearly that the noise levels in images reconstructed by use of the halfscan-hybrid algorithm are generally lower and spatially more uniform than are those in images reconstructed by use of the halfscan-FFBP algorithm. Such reduced and uniform image noise levels may be translated into improvement of the accuracy and precision of lesion detection and parameter estimation in noisy CT images without increasing the radiation dose to the patient. Therefore, the halfscan-hybrid algorithms may have significant implication for image reconstruction in conventional and helical CT. 相似文献
97.
Anaplastic carcinomas in nude mice and in original donor strain rats inoculated with cultured oval cells. 总被引:1,自引:5,他引:1 下载免费PDF全文
H. Yoshimura R. Harris S. Yokoyama S. Takahashi M. A. Sells S. F. Pan B. Lombardi 《The American journal of pathology》1983,110(3):322-332
Male Sprague-Dawley rats were fed for 4-5 weeks a choline-devoid diet containing 0.1% DL-ethionine. Preparations of nonparenchymal epithelial cells, enriched in oval cells, were isolated from the livers of these animals and were placed in culture. Six lines of hepatic epithelial cells were thus established. The lines underwent transformation after several passages, became tumorigenic in nude mice and 3 lines also in rats of the same strain of origin of the isolated cells. The tumors were uniformly highly anaplastic carcinomas. Preliminary morphologic, cytologic, and cytochemical results were consistent with the tumoral cells being hepatocytelike cells. These findings are viewed and discussed in terms of the cellular source, in vivo, of longterm cultures of rat liver epithelial cells, and in relation to a possible role of hepatic nonparenchymal epithelial cells in the process of hepatocellular tumor induction by chemical carcinogens. 相似文献
98.
乙醇对人绒毛孕酮分泌的影响 总被引:1,自引:0,他引:1
本工作利用灌流技术观察了四种不同浓度的乙醇(0.5%、1%、2.5%、5%)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。 相似文献
99.
Conversion of myoblasts to physiologically active neuronal phenotype 总被引:13,自引:0,他引:13
Watanabe Y Kameoka S Gopalakrishnan V Aldape KD Pan ZZ Lang FF Majumder S 《Genes & development》2004,18(8):889-900
100.
GABA- and glutamate-mediated synaptic potentials in rat dorsal raphe neurons in vitro 总被引:1,自引:0,他引:1
1. Synaptic potentials were recorded with intracellular electrodes from rat dorsal raphe neurons in a slice preparation. 2. Synaptic potentials were evoked by applying electrical pulses to bipolar stimulating electrodes positioned immediately dorsal to the raphe nucleus; these arose after a latency of 0.5-5 ms and had a duration of 20-200 ms. 3. The synaptic potential was biphasic (at the resting potential) when the recording electrodes contained potassium citrate; a depolarization was followed by a hyperpolarization. The hyperpolarization reversed in polarity at -70 mV and was blocked by bicuculline. 4. The depolarizing synaptic potential was reduced to 50-90% of control by kynurenate (1-2 mM) or 6-cyano-2,3-dihydroxy-7-nitro-quinoxaline (CNQX) (10 microM) and increased in amplitude and duration by magnesium-free solution. 5. In magnesium-free solutions (with CNQX), the depolarizing synaptic potential was blocked by DL-2-amino-5-phosphonovaleric acid (APV, 50 microM). APV also blocked depolarization caused by adding N-methyl-D-aspartate (NMDA) to the superfusion solution. 6. The results indicate that raphe neurons display two synaptic potentials having a duration of 150-200 ms: one that is mediated by GABA and a second that is due to an excitatory amino acid. The component mediated by an excitatory amino acid involves, in part, a receptor of the NMDA type. 相似文献