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21.
Neurons in the monkey cerebral cortex containing nicotinamideadenine dinucleotide phosphate-diaphorase (NADPH-d) can he dividedinto two distinct types, both nonpyramidal. Type I neurons havea large soma (diameter 20–50 µm), a dense NADPH-dhistochemical reaction. and are distributed throughout the cortex,but mainly in the subcortical white matter, and are mostly aspiny.Type II cells have a small soma (< 20 µm) with lightNADPH-d reactivity and are distributed primarily in the supragranularlayers, particularly layers II and upper III. The numericaldensity of type II cells is much greater than that of type I.Type I neurons also stain for GABA and a few intracortical typeI cells contain calbindin. All type II cells found here arecolocalized with both GABA and calbindin. Neither type I nortype II cells are stained for parvalbumin. Together with previous observations that almost all corticalNADPH-d cells in various subprimates are like type I cells,we suggest that type II cells may form a group of NADPH-d-richneurons differentiated in higher mammalian cortex from a subpopulationof calbindin-containing GABAergic interneurons, and these nitricoxide-synthesizing cells may play a role in control of intracorticalneuronal activity characteristic of higher cerebral functionsin advanced mammals.  相似文献   
22.
目的 解决南方红豆杉细胞生长缓慢及代谢水平低下的问题。方法 对对数期(20d)和静止期(30d)的红豆杉细胞分别进行继代,在整个生长周期中测定了培养基中的碳源、氮源、磷酸盐的变化并分析了红豆杉细胞生长及紫杉醇的合成情况。结果 对数期继代细胞吸收碳源和硝态氮早于静止期继代的细胞,且前者的比生长速度是后者的1.5倍,紫杉醇含量提高了近4倍。结论 对数期继代有利于生物量的积累及紫杉醇的合成。  相似文献   
23.
The subdivisions of the sacral intermediolateral nucleus (IML) of the cat have been studied by using a double-labeling technique of retrograde Fluoro-gold (FG) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) tracing. The parasympathetic preganglionic neurons (PGNs) that were labeled by the FG injected into the pelvic nerve formed a ‘V’-shaped column known as the sacral parasympathetic nucleus (SPN) in the sacral IML. The neurons that were labeled by the WGA-HRP applied to the lateral parabrachial nucleus (PBL) formed an elongated spindle-shaped column extending throughout the IML of the sacral segments. We designated it by the name of sacral visceral sensory nucleus (SVSN). These findings indicate that the sacral IML of the cat contain two distinct subdivisions, SPN and SVSN.  相似文献   
24.
The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsPs) and inositol 1,4,5-trisphosphate (InsP3) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF4-stimulated formation of [3H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [3H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage.  相似文献   
25.
本文对103名高龄老人进行营养情况调查、心理状况调查和体测量,结果表明:高龄老人体质指数大于26者很少,只要老龄人的各种营养素达到供给量标准,心理状态乐观满意,且不吸烟不酗酒者,则可长命百岁。  相似文献   
26.
We have adapted the simple and sensitive McAb-antigen spot test (AST) for evaluating the efficacy of anti-Leishmania chemotherapy. Serum samples from 37 kala-azar patients were tested by McAb-AST, and all showed definite positive reactions before treatment. After a course of antimony treatment, 20 turned negative, coupled with the disappearance of clinical symptoms; another 12 cases responded with weak positivity accompanied by an improvement of clinical manifestations; and the remaining 5 antimony-resistant patients showed strong positive reactions, with their conditions gradually worsening. Furthermore, all 6 cases in which the diagnosis was missed by the bone marrow smear method turned McAb-AST negative after chemotherapy. These results suggest that McAb-AST can be used to evaluate the efficacy of chemotherapy as well as to avoid missed diagnosis by the bone marrow smear method.  相似文献   
27.
经蝶垂体腺瘤手术后残留原因分析   总被引:1,自引:0,他引:1  
目的:探讨经蝶切除垂体腺瘤手术后残留的原因,提高治疗效果;方法:回顾性分析自1992年10月至2003年1月,在我院及外院经蝶手术治疗后,MRI检查证实仍有残留的118例垂体腺瘤。结果:肿瘤主体残留在海绵窦占46.6%,鞍内37.3%,鞍上5.1%,混合9.3%,颅外1.7%;影响肿瘤根除的主要因素,肿瘤侵袭海绵窦46.6%,术者经验不足36.4%,肿瘤侵润生长9.3%,肿瘤体积巨大3.4%,出血多4.2%。针对残余瘤组织再手术者为10.1%,普通放射治疗39.0%,r刀治疗38.2%,药物治疗11.0%。结论:经蝶手术残瘤的主要原因是肿瘤侵袭海绵窦,这些病例不能或很难单纯手术根除;其次是术者经验不足和技术问题而造成。在有残瘤的病例中,有半数以上病例可以通过提高技术水平达到肿瘤的全切或次全切除。  相似文献   
28.
缺血性脑血管病患者的血脂水平   总被引:4,自引:0,他引:4  
目的分析缺血性脑血管病(ICVD)患者的血脂水平,为今后预防保健及康复干预决策的制定提供依据。方法在佛山市第一人民医院病案数据库中检索1991-2004年诊断为ICVD的病例共2886例,其中2000-2004年ICVD患者共1430例为一亚组,以我院同时期保健科随机选取的400名健康体检人群为对照组,记录血脂情况,进行对照分析。结果血TC、TG和LDL—C水平ICVD患者组明显高于健康体检人群,差异有统计学意义。男女两性血脂水平均随年龄增加而逐渐增高,50岁以上女性血脂水平明显高于同龄组男性。血脂代谢异常患病率随着年代的推移呈逐步上升趋势,总胆固醇从1991—1994年的24.5%到2001-2004年的38.1%(男性)和22.3%到38.5%(女性),且明显高于国内2000-2001年普查人群高脂血症的患病率。结论佛山地区血脂异常是ICVD的重要原因之一。  相似文献   
29.
Senile macular degeneration   总被引:1,自引:0,他引:1  
M Yan 《中华眼科杂志》1987,23(6):313-6, 21
  相似文献   
30.
In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined.Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionaaly,morphologically and immunohistologically,at serial intervals up to 52 weeks after transplantation.Allograft recipients developed progressive proteinuria after 12 weeks,with gradual renal failure ultimately leading to death.At the same time,morphological changes,including progressive arteriosclerosis and glomerulosclerosis ,tubular atrophy and interstitial fibrosis,developed.Immunohistologically,macrophages infiltrated glomeruli during this period and cytokines became unregulated.Our results showed that antigen-independent functional and morphological changes occurred in long-tern kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes.  相似文献   
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