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51.
对伴有相对性瞳孔反射传入障碍(RAPD)的26例非对称性青光眼(17例原发性开角型青光眼和9例青睫综合征)患者,将RAPD定量值与其两眼视野面积差值(VFAD)进行相关分析。结果显示Ⅰ2e、Ⅰ4e和Ⅲ4e等视线VFAD与RAPD值的相关系数分别为0.70、0.81和0.88,各相关系数经统计学检验均有极显著意义(P<0.001)。表明RAPD测量在揭示青光眼不对称性视功能损害方面与视野检查具有一致性。因而RAPD可以作为非对称性青光眼视功能损害的重要体征之一。 相似文献
52.
A monoclonal antibody to the molluscan small cardioactive peptide SCPB and a polyclonal antibody to FMRFamide were used to localize antigens in the stomatogastric nervous system and brain of two species of Cancer. Both antibodies labeled cell bodies, axons, and neuropilar processes in the brain and in the stomatogastric nervous system. All of the SCPB immunoreactive neurons were co-labeled with antibody to FMRFamide. However, antibody to FMRFamide labeled additional neurons of the commissural ganglion and the brain that were not immunoreactive to the monoclonal SCPB antibody. 相似文献
53.
A. C. Metting van Rijn A. Peper C. A. Grimbergen 《Medical & biological engineering & computing》1991,29(4):433-440
A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is
described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications
with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination
of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an
input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel
version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6
mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured
with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels.
The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies
the power supply in stationary measurement systems. 相似文献
54.
目的:探讨小瞳孔状态下应用削梨法超声乳化的手术技巧和注意事项。方法:应用削梨法超声乳化技术对69例(78只眼)小瞳孔白内障行超声乳化。结果:无虹膜后粘连63只眼,术后全部瞳孔恢复原状;15只眼分离粘连机化膜后应用削梨法进行超声乳化,术后13只眼基本恢复圆瞳孔,2只眼瞳孔不规则。术后3个月裸眼视力≥05者43只眼(55.13%).矫正视力≥05者61只眼(78.21%)。结论:削梨法受瞳孔大小的限制较小,大大降低了手术操作的难度,减少了手术的危险性,不失为小瞳孔白内障超声乳化的好办法。 相似文献
55.
56.
目的了解表皮生长因子(epidermalgrowthfactor,EGF)对移植小肠通透性及细菌易位的作用。方法以Wistar大鼠为供体,SD大鼠为受体行异位全小肠移植,并以环孢素A(CsA,6mg.kg-1.d-1,im)抑制排斥反应。表皮生长因子组(EGF组)用微量输液泵持续均匀输入EGF200μg.kg-1.d-1;对照组输入等量生理盐水。第7天以乳果糖及甘露醇行移植肠灌注并收集尿液行高效液相色谱仪分析乳果糖及甘露醇含量,第8天采集移植肠系膜淋巴结及门静脉血行细菌培养。结果对照组尿液中乳果糖含量[(0.093±0.008)vs(0.015±0.002),P=0.0001]及乳果糖/甘露醇比值[(0.132±0.021)vs(0.020±0.005),P=0.0001]明显高于基准,EGF组乳果糖含量[(0.043±0.008)vs(0.015±0.002),P=0.0054]及乳果糖/甘露醇比值[(0.060±0.017)vs(0.020±0.005),P=0.0029]也较基准增加,EGF组乳果糖含量[(0.043±0.008)vs(0.093±0.008),P=0.0067)及乳果糖/甘露醇比值[(0.060±0.017)vs(0.132±0.021),P=0.0116]显著低于对照组。EGF组移植肠系膜淋巴结细菌阳性率为10%,对照组阳性率为60%,明显高于EGF组(P=0.028)。EGF组与对照组门静脉血培养阳性率比较差异无统计学意义(P>0.05)。结论本研究提示EGF能够降低同种移植小肠的通透性及细菌易位率,改善肠黏膜屏障功能。 相似文献
57.
目的构建并筛选大鼠胶质原纤维酸性蛋白(GFAP)表达抑制短发夹样RNA(shRNA)真核表达载体。方法针对GFAP基因全编码序列设计并合成三对9bp茎环结构、19bp干扰序列特异性shRNA模板,体外定向克隆构建特异性重组质粒真核表达载体;通过体外大鼠脊髓源星形胶质细胞GFAP表达抑制模型,脂质体介导RNA干扰分子转染,实时荧光定量RT—PCR及Wesem blot技术观察RNA干扰后原代星形胶质细胞GFAP表达抑制效果.筛选最佳GFAP表达干扰抑制真核表达载体。结果序列测定证实GFAP—shRNA重组质粒真核表达载体构建成功,三对shRNA模板在mRNA及蛋白表达水平抑制靶基因表达效率分别为81%、63%、56%。结论高效率的GFAP—shRNA真核表达载体在大鼠原代星形胶质细胞GFAP表达抑制模型中能高效抑制GFAP基因表达,为后续多靶点RNA干扰技术在脊髓损伤胶质瘢痕抑制基因治疗中的应用奠定了前期基础。 相似文献
58.
Ken Yamaguchi Katsumi Aoyagi Ken-ichi Urakami Toyoharu Fukutani Noboru Maki Shigehiro Yamamoto Kotomi Otsubo Yoshio Miyake Tetsuro Kodama 《Cancer science》1995,86(7):698-705
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients. 相似文献
59.
60.
Exposure of H69 small cell lung carcinoma cells to nicotinic agonists resulted in a significant increase (up to 100%) in cell number after 6 to 12 days. The effect of nicotine (10−8 M to 10−4 M) was both dose and time dependent as was that of another nicotinic agonist cytisine (10−6 M to 10−4 M). Interstingly, both the nicotine and cytisine induced increases in H69 cell number were blocked by α-bungarotoxin, as well as d-tubocurarine a nicotinic blocker which appears to interact with most nicotinic receptors. These results suggest that the nicotine induced increase in cell number is mediated through an interaction at the nicotinic α-bungarotoxin receptor. This idea is further supported by experiments which show (1) that H69 cells possess high affinity α-bungarotoxin sites (Kd = 25 nM, Bmax = 10.4 fmol/106 cells) with the characteristics of a nicotinic α-bungarotoxin receptor and (2) that the potencies of nicotinic receptor ligands in the α-bungarotoxin binding assay were similar to those observed in the functional studies. Northern analysis showed that mRNA for α7, a putative nicotinic α-bungarotoxin binding subunit, and for α5 were present in H69 cells. The present data provide further evidence that nicotine increases cell number in small cell lung carcinoma and are the first to show that this effect is mediated through an interaction at the nicotinic α-bungarotoxin receptor population. These results suggest that the α-bungarotoxin site may be involved in modulating proliferative responses in neuroendocrine derived SCLC cells. 相似文献