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61.
Because some evidence suggests that cocaine and GBR12935 bind to different sites, we utilized photoaffinity probes from both classes of compounds to see if they label the same protein. [125I]RTI-82 a cocaine analog, and [125I]DEEP, a GBR analog, labeled protein(s) showing the same molecular weight, a similar pharmacological profile and a similar sensitivity to neuraminidase.  相似文献   
62.
L Gao  J M Kennedy 《Muscle & nerve》1992,15(3):419-429
Ventricular-like and fast myosin heavy chains (VL-MHC and FMHC) are transiently expressed during slow skeletal muscle development. The influence of innervation on repression of these MHC isoforms is investigated over an 84-day time course in: (1) normal anterior latissimus dorsi (N-ALD) muscles, (2) regenerating ALD (R-ALD) muscles, (3) denervated ALD (D-ALD) muscles, and (4) regenerating and denervated ALD (RD-ALD) muscles. Western blotting demonstrates that the VL-MHC is expressed in R-, D-, and RD-ALD muscles, but not in N-ALD muscles. Expression of the VL-MHC is transient in R-ALD muscles. In contrast, VL-MHC expression persists in RD-ALD muscles, and appears with time in D-ALD muscles. FMHC was not detected in N-ALD muscles by Western blotting. Two FMHCs are seen in R-ALD and RD-ALD muscles, and in 13-day embryonic ALD muscles. The slower migrating FMHC (FMHCA) comigrates with developmentally regulated FMHCs in fast pectoralis muscle, while the faster migrating FMHC (FMHCB) comigrates with the faster migrating FMHC in embryonic ALD muscle (13 days in ovo). FMHCB decreases in amount over the time course in R-ALD muscles, while FMHCA persists. In contrast, substantial levels of both FMHCs persist in RD-ALD muscles, and appear with time in D-ALD muscles. The cellular distribution of MHCs is followed by immunocytochemistry. Regenerating cells expressing VL-MHC and FMHC are replaced by a mature population in R-ALD muscles. Some of the mature myofibers in R-ALD muscles express FMHC, but not VL-MHC. In RD-ALD and D-ALD muscles, both regenerating and mature muscle cells are seen which express VL-MHC and FMHC. Our results indicate that innervation is required for the repression of VL-MHC and FMHCB during regeneration of slow muscle.  相似文献   
63.
64.
Non-digestible oligosaccharides — potential anticancer agents?   总被引:1,自引:0,他引:1  
  相似文献   
65.
Transitional mucosa adjacent to colorectal cancers is essentially characterized by an excess of sialomucins at the expense of the normally predominant sulphomucins in epithelial cells lining the intestinal crypts which presents the early stage of oncogenic transformation of colorectal epithelium. The presence or absence of sialomucins at the resection margins was studied histochemically using the high iron diamine-alcian blue(HID-AB) stain in 64 rectal cancer patients in Dukes' B stage who underwent curative anterior resection. The correlation was revealed between the presence of sialomucins at the resection margins and subsequent development of local tumour recurrence. Fourteen of 27 patients (51.9%) with sialomucins predominant pattern at either resection margin developed local recurrence compared with 4 of 37 patients (10.8%) with sulphomucins predominant pattern (P less than 0.001). It is suggested that determination of the transitional mucosa around anastomosis in patients treated for the rectal carcinoma by anterior resection appears to identify those with a higher risk of local recurrence.  相似文献   
66.
Cardiac ultrasound and upper gastrointestinal endoscopy are relatively old technologies. With the introduction of new ultrasound probes and by incorporating ultrasound technology into conventional endoscopes, ‘new tricks’ in cardiac imaging were discovered. Posterior structures of the heart are now able to be imaged clearly by the ultrasound probe from the oesophagus. Consequently, better resolution of cardiac anatomy allows more accurate diagnosis of cardiac pathologies which is not possible using conventional transthoracic (TT) approach. Over a period of two years, 1200 cases of transoesophageal echocardiography (TOE) were undertaken in our institution. The major indications were diseases of the aorta (10%), source of cardioembolism (28%), assessment of native and prosthetic valve function (20%), suspected endocarditis and its complication (17%), pre and post percutaneous transluminal mitral valvotomy (PTMV [13%], congenital heart disease (2%) and others (10%). The greatest impact with TOE is in the diagnosis of aortic dissection and transection, TOE is superior to conventional TT approach in detecting potential source of embolism, valvular vegetations and its complication, native and prosthetic valve dysfunction and LA thrombus prior to PTMV. Observations by TOE such as spontaneous echo contrast (SEC) in the left atrium open new challenges for further research in its role in the pathogenesis of LA thrombus and its association with cardioembolic event. Other areas of interest include; reclassification of distal aortic dissection and the use of TOE in intra-operative work.  相似文献   
67.
68.
健康和病变人声带振动特性声门图   总被引:1,自引:0,他引:1  
本文用多功能声门图仪测定了健康受试者(男46名,女34名)和不同喉病患者(男134名,女87名)声门图的波形及其特征参数。根据测出的正常声门图及其参数分布研究了恶性喉病变、声带麻痹、喉内关节病变、功能性声门发声障碍、声带息肉、声带小结、喉炎和早期喉病的临床声门图表现及其与声带振动模式变异之间的关系,并探讨了上述病变声门图的鉴别诊断指标和用声门图对喉病手术治疗、药物治疗和功能治疗的疗效进行定性和定量评价。研究结果证实:声门图方法能准确、定量、灵敏地反映声带振动模式及其变异;在喉病诊治中具有重要的应用价值。  相似文献   
69.
70.
本文报导采用现代玻璃体手术结合巩膜扣带、空气或硅油填塞治疗81例伴严重增殖性玻璃体视网膜病变(PVR)视网膜脱离的手术效果.经过6~28个月(平均14个月)的随访,视网膜完全平伏者54例,成功率66.7%,对极严重的PVR D(?)(闭斗状脱离)也取得50%的成功率.硅油填塞初步应用于极严重病例尤其是巨大裂孔的治疗,取得明显的效果.本文病例术后视力提高者50例,不变19例,下降12例,术后视力在0.05以上者共34例.认为玻璃体手术结合其它技术是伴严重PVR手术治疗的有效方法,提出进一步提高PVR治疗成功率的方法:彻底清除增殖膜及寻找一种有效抑制膜增殖而对眼内其它组织无毒性的药物。指出旧的PVR分级法存在的不足,推荐用于硅油研究的PVR新的分级法.  相似文献   
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