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31.
32.
为探讨脂质过氧化损伤及自由基在新生儿硬肿症发病机理中的作用,将观察对象分为疾病组和对照组,疾病组于入院时,对照组于出生后1周内取静脉血检测血浆脂质过氧化物及红细胞超氧化物歧化酶含量。 相似文献
33.
本文报告113例脑前循环系统动脉管其中包括颈内动脉后交通动脉瘤75例.前交通动脉瘤17例,大脑中动脉瘤10例,人脑前动脉-胼周动脉瘤3例,颈内动脉-眼动脉瘤2例,颈内动脉海绵窦段动脉瘤1例.多发动脉瘤5例.共118个动脉瘤在显微镜下直视手术,动脉瘤直接夹闭术108例.孤立或包裹术5例:5例多发动脉瘤行同期手术3例,分期手术2例.术中发生动脉瘤破裂18次.Hunt和HessⅠ~Ⅱ级病人中有例行早期手术.全组术后死亡率为7.9%.着重讨论手术时机.术中动脉瘤破裂处理及多发动脉瘤的治疗. 相似文献
34.
Chronicsofttissuelesionisaspeciallymedicalterm,andanimportantpathologicalchangesofdiseases,suchaschronicoveruseinjuriesandconversionofacuteinjuriesinlowbackorfrominter-vertebraldiscprotrusion,anddislocationofintervertebraljointsaswell,whichmainlycauseseverepaininlowback犤1犦.Manypresentmethods(oralmedicine,massage,anestheticblock,physicalthera-piesetc.)havebeenusedforrelievingthepain,whichdemandsagreatfiscalsupportannually.Unfortunately,thereportsonthemechanismsandeffectofthem… 相似文献
35.
目的 通过测定生长激素缺乏症 (GHD)患儿用国产重组人生长激素 (recom bined hum angrowth horm one,rh GH)治疗时血清生长激素抗体 (GH- Ab)水平及其结合特性 ,探讨 rh GH的免疫原性及其对疗效的影响。方法 对 6 1例 (男 49例 ,女 12例 ) GHD患儿用国产 rh GH治疗 ,每晚睡前皮下注射 rh GH 0 .1IU /kg共6个月 ;用放射免疫法测定治疗期间患儿血清 GH- Ab水平和滴度 ,并计算抗体结合容量、亲和常数 (Ka)。结果 48%患儿 (2 9/6 1)用药后 3个月血清 GH - Ab呈阳性至试验结束时仍未消失 ,其中 2 0例抗体为弱阳性 (结合率 <10 % ) ,9例呈强阳性 (结合率 >15 % ) ;5 2 %患儿 (32 /6 1)治疗期间抗体为阴性 ;血清 GH- Ab的结合容量、Ka及滴度均为低水平 ,分别为 (0 .1~ 4.8) pmol/L、(1.7× 10 7~ 6 .5× 10 8) L /mol和 1∶ 4~ 1∶ 8。GH- Ab阳性患儿治疗后的身高、身高增长速率及身高落后于正常 SD值的变化与同期阴性者比较无统计学差异 (P>0 .0 5 )。结论 本试验所用国产 rh GH对 GHD患儿身高增长具有确切的促进作用 ,其免疫原性所导致产生的 GH - Ab未对患儿体格线性增长产生负性影响 相似文献
36.
Electrical coupling is widespread in developing nervous systems and plays a major role in circuit formation and patterning of activity. In most reported cases, such coupling between rhythmogenic neurons tends to synchronize and enhance their oscillatory behavior, thereby producing monophasic rhythmic output. However, in many adult networks, such as those responsible for rhythmic motor behavior, oscillatory neurons are linked by synaptic inhibition to produce rhythmic output with multiple phases. The question then arises whether such networks are still able to generate multiphasic output in the early stage of development when electrical coupling is abundant. A suitable model for addressing this issue is the lobster stomatogastric nervous system (STNS). In the adult animal, the STNS consists of three discrete neural networks that are comprised of oscillatory neurons interconnected by reciprocal inhibition. These networks generate three distinct rhythmic motor patterns with large amplitude neuronal oscillations. By contrast, in the embryo the same neuronal population expresses a single multiphasic rhythm with small-amplitude oscillations. Recent findings have revealed that adult-like network properties are already present early in the embryonic system but are masked by an as yet unknown mechanism. Here we use computer simulation to test whether extensive electrical coupling may be involved in masking adult-like properties in the embryonic STNS. Our basic model consists of three different adult-like STNS networks that are built of relaxation oscillators interconnected by reciprocal synaptic inhibition. Individual model cells generate slow membrane potential oscillations without action potentials. The introduction of widespread electrical coupling between members of these networks dampens oscillation amplitudes and, at moderate coupling strengths, may coordinate neuronal activity into a single rhythm with different phases, which is strongly reminiscent of embryonic STNS output. With a further increase in coupling strength, the system reaches one of two final states depending on the relative contribution of inhibition and inherent oscillatory properties within the networks: either fully synchronized and dampened oscillations, or a complete collapse of activity. Our simulations indicate that, beginning from either of these two states, the emergence of distinct adult networks during maturation may arise from a developmental decrease in electrical coupling that unmasks preexisting adult-like network properties. 相似文献
37.
作者用自制的[~(125)I]标记激素,参考国外经验,建立了人血清胰岛素抗体、猪胰岛素原抗体和胰多肽抗体等三种放射免疫检测法,并对方法的主要实验条件进行了优选,对方法的质量控制参数作了验证。结果发现:在使用国产胰岛素的糖尿病人血清中,三种抗体的检出率分别为90.8%、48.3%和36.5%;抗体特异性结合值分别为21.2±17.4%、41.8±27.4%和25.6±28.4;而正常人和糖尿病人未用胰岛素者全部为阴性,显示国产胰岛素具有明显的免疫原性。 相似文献
38.
Peter D. Le Roux David S. Jardine Paul M. Kanev John D. Loeser 《Child's nervous system》1991,7(1):34-39
We reviewed the results of all pediatric patients undergoing intracranial pressure (ICP) monitoring in a 2-year period at our institution. The outcome of patients suffering hypoxia or ischemic injuries (HII) is compared to those suffering non-hypoxic or non-ischemic injuries (NHII). Thirty-four patients had ICP monitors placed during the study period. Inconplete patient information led to the exclusion of 5 patients. An additional 5 patients were excluded because no measures to control ICP were taken after the monitor was placed. Twenty-four patients required treatment for raised ICP (hyperventilation, 24; mannitol, 19; barbiturate coma, 6). Admission Glasgow Coma Score in patients suffering HII (median score 5) and NHII (median score 6) were not significantly different (Mann-Whitney U Test). Only 2 of 8 patients with HII were near-drowning vietims. The remaining 6 had HII from other causes (5 survivors of various forms of asphyxia and 1 of cardiac arrest). All 8 patients had poor outcomes (1 severely disabled; 7 died). The 16 patients with NHII had a variety of diagnoses (6 trauma, 5 encephalitis, 4 bacterial meningitis, 1 diabetic ketoacidosis). Among these, 6 had good outcomes and 10 poor outcomes (2 severely disabled, 2 vegetative, and 6 died). The difference in outcome between patients with NHII and HII is significant at P=0.059 (Fischer Exact test). Patients with NHII may benefit from ICP monitoring. Patients with HII from near-drowning and other causes did not appear to benefit from ICP monitoring and interventions directed at controlling ICP. 相似文献
39.
D Mabin J P Borsotti S Tea J C Le Mevel J Clavier 《Revue d'électroencéphalographie et de neurophysiologie clinique》1986,15(4):341-348
Eleven patients with bronchial epidermoid carcinoma and undergoing treatment with cis-D.D.P. (II) were kept under electrophysiological and clinical surveillance. No other neurotoxic medication was added. The total dose of cis-D.D.P. was 300 mg/m2 over a period of three months: namely, three courses of 100 mg/m2 distributed over 5 days. Following the pretreatment check-up, the patients were divided into two groups: those without any electrophysiological abnormality (group A), and those without clinical abnormality but with a delayed latency H of the Hoffmann Reflex (group B). Patients in group A showed a slowing down of the motor nerve conduction velocity of the Median and Peroneal Nerves after a course of 100 mg, without accompanying worsening of the conduction velocity after 300 mg/m2, and prolongation of the distal latency of the sensory Median Nerve after 300 mg/m2; in group B, no significant change of electrophysiological clinical features were noted. In the two groups a non-significant reduction in amplitude of evoked responses were noted. These findings are more consistent with an axonal injury than with functional myelin injury. The authors review the existing literature and discuss the physiopathologic mechanisms of cis-D.D.P. peripheral neuropathies. 相似文献
40.
目的:探讨EB病毒感染与人大肠癌发生的关系。方法:用原位分子杂交法对130例人大肠癌标本中EB病毒小分子RNA片段进行检测。结果:130例标本中有6例(4.48%)癌组织呈阳性反应,其中4例为男性,4例有明显淋巴细胞浸润。结论:EB病毒感染可能与我国部分大肠腺癌的发生有关,肿瘤细胞间质中大量淋巴细胞浸润可能是EB病毒感染的重要病理学特征。 相似文献