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71.
Summary. Acute promyelocytic leukaemia (APL) is characterized by t(15;17)(q24;q21). Trisomy 8 is the commonest accompanying karyotypic aberration. We investigated 14 APL patients for trisomy 8 using fluorescence in situ hybridization (FISH). Conventional cytogenetic analysis showed trisomy 8 in two of nine successfully karyotyped cases. With FISH, a possible third case showing a subclone (1-2-5%) with trisomy 8 was found. The trisomy 8 clone size defined by karyotyping and FISH was concordant in one case and discordant in another, in which trisomy 8 was found in 100% of metaphases but only in 48% of leukaemic prbmyelocytes by FISH. Therefore trisomy 8 was mosaic in all the cases, suggesting that it had arisen from clonal evolution. AU-trans-retinoic acid successfully induced morphologic remission in both cases with trisomy 8.  相似文献   
72.
足组织缺损的显微修复   总被引:15,自引:11,他引:4  
1984年~1994年共收治各种足部组织创伤缺损236例,均采用显微外科技术进行组织移植修复,其中单纯皮瓣移植修复187例,复合皮瓣移植修复49例。吻合血管游离移植修复97例,带血管蒂移位修复139例。4例前足缺损者用带肩胛骨的复合皮瓣移植修复,6例足跟严重缺损者用带血管的腓骨复合皮瓣移植修复。经1~10年随访,皮瓣、复合皮瓣、移植或再植的骨骨各全部成活,愈合良好,足功能基本得到恢复,可行走、负重,186例恢复了原工作。认为,恢复足部结构完整与重建足跟、足底的感觉是获得良好功能的关键  相似文献   
73.
Summary Nerve regeneration was studied in a model of centrocentral anastomosis (CCA) performed on the sciatic nerve of the rat. Experimental CCA was made by suturing the proximal end of the peroneal branch on the proximal end of the sural branch, placing between them a peroneal nerve graft (Group I, 20 rats) or a silicone chamber (Group II, 12 rats). Nerve grafts had a length of 5mm and silicone chambers 7 mm. In six silicone chambers an 1 mm nerve graft was placed in the centre of the tube. In group I animals anterograde degeneration was studied by cutting the graft 60 days after surgery. In group II, nerve regeneration was studied 2, 4 and 8 weeks after surgery. Results indicate that in CCA: 1) regenerated axons coming from one nerve end grow into the graft but do not cross the contralateral suture line; 2) regeneration is poorer in silicone chambers than in nerve grafts; and, 3) in silicone chambers regeneration is related to time. The reduction in the regenerative capability in CCA seems to be related to the alteration of nerve sprouts aiming for the peripheral targets.  相似文献   
74.
Using a plasma separator, it is possible to wash large volumes of whole blood free of plasma proteins in short periods. The novelty, however, is that the same apparatus can be used to reversibly hemolyze and reseal the red blood cells (RBCs) using hypotonic and hypertonic dialysates, respectively. This technique was assessed using the fluorescent exogenous agent uranin (fluorescein sodium). Results indicate that the encapsulation of the RBCs can be completed in under 2 h. The encapsulation efficiency of the RBCs was approximately 80% with a RBC recovery rate of 75%.  相似文献   
75.
以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。  相似文献   
76.
Purpose It was the aim of this study to investigate the efficacy, longevity, and safety of a new ab interno intervention for the treatment of primary open-angle glaucoma (POAG). Methods The previously described method of radiofrequency-mediated “sclerothalamotomy ab interno” was applied in 53 eyes of consecutive patients with POAG between April 2002 and July 2002. Average preoperative intraocular pressure (IOP) was 25.6±2.3 mmHg (range 18–48 mmHg). Sclerothalamotomies were carried out with a custom-made high-frequency dissection 19 G probe (tip 0.3×1 mm) applying bipolar current with a frequency of 500 kHz (tip temperature 130°C). Results After a follow-up period of 24 months, the average IOP was 15.0±1.6 mmHg (range 11–20 mmHg) (p<0.005). The average number of topical agents was 2.6±1.0 (range 1–5) preoperatively. Twenty-four months after surgery such agents were used in only five (9.6%) eyes and the average was 0.21±0.53 (range 0–2). Transient IOP elevation was observed in 12 of 53 eyes (22.6%) postoperatively. In all cases elevated IOP could efficiently be controlled with topical medication. In general, IOP dropped continuously over the course of the 6 months following surgery and then remained constant. Conclusions This study indicates that sclerothalamotomy ab interno is a safe and efficient surgical method for the treatment of POAG. Long-term results clearly demonstrate the longevity of IOP reduction.  相似文献   
77.
Objective: To study the rapid effect of glucocorticoids (GCs) on NMDA receptor activity in hippocampal neurons in stress and to elucidate its underlying probable membrane mechanisms. Methods: Whole-cell patch-clamp recording was used to assess the effect of stress concentration corticosterone (B) on the responses of cultured hippocampal neurons to glutamate and NMDA (N-methy-D-asparatic acid). To make clear the target of B, intracellular dialysis of B(10μmol/L)through patch pipette and extracellular application of bovine serum albumin-conjugated corticosterone (B-BSA, 10μmol/L)were carried out to observe their influence on peak amplitude of NMDA-evoked current. Results: B had a rapid, reversible and inhibitory effect on peak amplitude of GLU-or NMDA-evoked current in cultured hippoeampal neurons. Furthermore, B-BSA had the inhibitory effect on INMDA as that of B, but intraeeUularly dialyzed B had no significant effect on INMDA. Conclusion: These results suggest that under the condition of stress, GCs may rapidly, negatively regulate excitatory synaptic receptors-glutamate receptors (GluRs), especially NMDA receptor (NMDAR) in central nervous system, which is mediated by rapid membrane mechanisms, but not by classical, genomic mechanisms.  相似文献   
78.
论现代医院技术创新   总被引:4,自引:0,他引:4  
任真年 《中国医院》2003,7(8):43-45
创新是医院发展主题,本文采用综合分析、收集资料、对比方法,对技术创新内容、技术创新原则、技术创新趋势进行了较详细的分析研究.  相似文献   
79.
Fast T(1) mapping techniques are a valuable means of quantitatively assessing the distribution and dynamics of intravenously or orally applied paramagnetic contrast agents (CAs) by noninvasive imaging. In this study a fast T(1) mapping technique based on the variable flip angle (VFA) approach was optimized for accurate T(1) quantification in abdominal contrast-enhanced (CE) MRI. Optimization methods were developed to maximize the signal-to-noise ratio (SNR) and ensure effective RF and gradient spoiling, as well as a steady state, for a defined T(1) range of 100-800 ms and a limited acquisition time. We corrected B(1) field inhomogeneities by performing an additional measurement using an optimized fast B(1) mapping technique. High-precision in vitro and abdominal in vivo T(1) maps were successfully generated at a voxel size of 2.8 x 2.8 x 15 mm(3) and a temporal resolution of 2.3 s per T(1) map on 1.5T and 3T MRI systems. The application of the proposed fast T(1) mapping technique in abdominal CE-MRI enables noninvasive quantification of abdominal tissue perfusion and vascular permeability, and offers the possibility of quantitatively assessing dilution, distribution, and mixing processes of labeled solutions or drugs in the gastrointestinal tract.  相似文献   
80.
目的运用介入方法建立犬颅内动脉分叉部囊状动脉瘤模型。方法6条犬全麻后,采用血管内介入方法,用冠状动脉球囊导管扩张右颈总动脉近段,再用可脱球囊于扩张段远端将其栓塞,制作成6个分叉部动脉瘤。分别于术后1、2、3d行DSA检查并切除动脉瘤做病理组织学检查。结果6条犬成功获得6个动脉瘤模型。动脉瘤的平均宽度和平均长度在3d内逐渐减少。结论犬动脉瘤模型较好地模拟了人颅内动脉瘤大小、形态及DSA表现,可用于介入治疗新材料、新技术的实验研究。本动脉瘤模型的建立快速、可靠、可重复性强。  相似文献   
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