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61.
环磷酰胺对家兔血液流变性的影响 总被引:3,自引:0,他引:3
观察抗肿瘤药物环磷酰胺(CTX)对家兔血液流变性的影响。结果显示:CTX给药组(10只)多项血液流变学指标明显异常,与正常对照组(8只)比较具有显著性差异(P<0.05~0.001),标志着CTX有引起高粘滞血症的作用。提示:恶性肿瘤病人应用CTX后,可加重原有的高粘滞血症。这一结果可作为肿瘤化疗并用活血化瘀及抗凝治疗的依据 相似文献
62.
油酸型呼吸窘迫综合征家兔的血液流变性改变及山莨菪碱的作用 总被引:4,自引:0,他引:4
对家兔油酸型呼吸窘迫综合征(RDS)组、油酸型RDS654-2治疗组和生理盐水治疗组的血液流变性进行了研究。结果表明油酸型RDS和生理盐水治疗组ηa、RI、TK均明显增高,OD、HCT显著降低;而654-2治疗组ηa、RI和ηp等均无明显变化。提示油酸型RDS存在高全血粘度血症。654-2可能通过抑制红细胞、血小板聚集等而降低全血粘度、减轻肺损伤 相似文献
63.
S. P. Perrett 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(2):115-124
Little is known about mechanisms used by the nervous system to encode time. In light of recent evidence, cerebellar cortex
involvement in the learned timing of conditioned eyelid responses shows promise as an area of investigation into neural timing
mechanisms. Lesion studies indicate that the cerebellar cortex is necessary for response timing, but do not rule out the possibility
that response timing is encoded afferent to the cerebellum. To differentiate between precerebellar and cerebellar cortical
timing mechanisms, rabbits were trained by pairing direct stimulation of mossy fibers in the cerebellum as the conditioned
stimulus (CS) with an eyeshock unconditioned stimulus (US). We find that individual animals can produce diffently timed conditioned
responses when trained with a mossy fiber CS that has been paired with the US at various interstimulus intervals. The fact
that differently timed responses can be conditioned using constant-frequency stimulation of an invariant subset of mossy fibers
as the CS suggests that timing information in the afferent input to the cerebellum is not essential. Two rabbits trained with
single-pulse stimulation in the cerebellum as the CS also learned differently timed conditioned responses; suggesting that
fiber recruitment during a stimulus train does not convey the necessary temporal coding to the cerebellar cortex. Together
with the lesion data, these findings suggest that the learned timing of conditioned eyelid responses occurs in the cerebellar
cortex.
Received: 25 August 1997 / Accepted: 12 January 1998 相似文献
64.
65.
Summary The cytoarchitectonic parcellation of the rabbit's neocortex has been investigated in 6 hemispheres which had been fixed by perfusion, embedded in paraffin and sectioned at either 9 m or 20 m in various planes. In addition to the classical method of microscopic observation, and automatic scanning procedure using an image analyser for measuring grey level indices was employed. By printing computer plots of various ranges of grey level indices, this method permits visualization of structural differences between various cytoarchitectonic fields. By evaluating the plots, cytoarchitectonic maps can be constructed which are based on objective data and therefore less influenced by subjective judgment than the maps obtained with the classical method. — In some regions the results based on the quantitative method are in agreement with the commonly used maps of Rose (1931), and in other regions widely at variance. It is shown, for instance, that the area striata as defined by Rose (1931) is composed of two distinct fields, viz. areas Oc 1 and 2, which are separated from each other in the rostro-caudal direction. These and other findings are described in detail, compared with the observations of Rose (1931), and related to the literature on functional localization in the rabbit's neocortex. Attention is drawn to the fact that the results obtained in 6 hemispheres leave no doubt that individual variations in size and shape of the entire hemisphere as well as of the various cytoarchitectonic fields do occur, and will have to be taken into account if cytoarchitectonic maps such as those published in the present paper are to be used in the context of experimental work. 相似文献
66.
Rubem Carlos Araujo Guedes Romualdo José do Carmo 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(3):341-349
Summary The ionic composition of the internal environment was altered in rabbits by means of gastric washing, combined with intramuscular administration of 3-Beta-aminoethylpyrazole. The effects of this treatment on cortical spreading depression (SD) were studied. C1- and Na+ concentrations decreased significantly in serum and in cerebrospinal fluid after the treatment. This made the animals much more susceptible to SD, as established by the high incidence of spontaneous SD, increased SD velocity of propagation and facilitated its interhemispheric transfer. An intensification of the epileptiform activity associated with SD was also observed. Intravenous replacement of NaCl abolished the above effects on SD. When the intravenous replacement was done with Na-Isethionate, those effects were enhanced. It is concluded that chloride deficiency was the main factor responsible for the observed facilitating effects.This work was supported by grants from the BNDE (FUNTEC-74 e 143), CNPq and CAPES 相似文献
67.
Gregory K. M. Giolli R. A. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,60(3):501-508
Summary The neurons of the medial terminal nucleus (MTN) of the accessory optic system (AOS) have been studied in the rat, rabbit and cat in Golgi-Cox and Golgi-Kopsch impregnated brain sections. The present anatomical findings permit a division of the MTN of these species into dorsal and ventral components (MTNd, MTNv), in agreement with other investigations. The MTNd contains predominantly linear-bipolar and linear-multipolar shaped neurons with cell bodies that measure in the range of 25–50 m. These neurons have 2 to 4 primary dendrites which, along with their smaller dendritic branches, are oriented in the plane of the long axis of the MTN (i.e. from ventromedial to dorsolateral). These linear-bipolar and linear-multipolar cells represent 70–80% of the neurons of the MTNd as seen in the Golgi impregnated sections. The remaining 20–30% of the MTNd neurons are nearly all multipolar in shape with somata measuring in the range of 15–25 m. An occasional multipolar neuron is larger, has a soma that measures around 30–60 m and has dendrites which extend outward from the cell body to cover large areas of the MTNd. There was considerable extension of the dendrites of MTNd neurons into the MTNv; however, the dendrites of MTNd neurons were not observed extending into the adjacent substantia nigra (SN) or ventral tegmental area (VTA) of Tsai (1925). Conversely, the dendrites of neurons in the neighboring SN and VTA course along the borders of the MTN but only occasionally extend into the MTN. The neuron population of the MTNv consists almost entirely of small-multipolar shaped cells with somata measuring from 15–25 m and dendritic trees resembling those described for multipolar cells of the MTNd. A small number of neurons of the ventral division are medium-multipolar in shape with cell bodies that measure approximately 30–60 m. Typically, these cells have several dendrites which extend ventrally within the MTNv and one or more dendrites that extend either across the MTNv or dorsally into the MTNd. Only a few linear-bipolar and linear-multipolar neurons were observed in the MTNv. The present findings are discussed in relation to anatomical, physiological, and histochemical studies on the MTN.Abbreviations to Figures CP
Cerebral Peduncle
- DTN
Dorsal Terminal Nucleus
- LG
Lateral Geniculate Nucleus
- LP
Lateral Posterior Nucleus
- MG
Medial Geniculate Nucleus
- ML
Medial Lemniscus
- MTNd
Medial Terminal Nucleus, dorsal division
- MTNv
Medial Terminal Nucleus, ventral division
- NTO
Nucleus of the Optic Tract
- PA
Anterior Pretectal Nucleus
- pn
Nucleus Paranigralis
- PP
Posterior Pretectal Nucleus
- Pul
Pulvinar
- PO
Olivary Pretectal Nucleus
- RN
Red Nucleus
- SGS
Stratum Griseum Superficiale, Superior Colliculus
- SN
Substantia Nigra
Supported by USPHS research grant EYO3642 from the National Eye Institute 相似文献
68.
69.
骨髓间充质干细胞复合羟基磷灰石/磷酸三钙植骨材料的体外研究 总被引:1,自引:1,他引:1
目的研究兔骨髓间充质干细胞(BMSCs)在羟基磷灰石/磷酸三钙(HA/TCP)植骨材料上的黏附增殖情况。方法抽取兔股骨骨髓,进行贴壁培养BMSCs。在成骨诱导液中诱导BMSCs,于7d用钙钴法检测碱性磷酸酶活性,10d进行茜素红矿化结节染色;在成脂诱导液中诱导BMSCs,于21d进行油红O染色。将BMSCs接种到HA/TCP植骨材料上,加入成骨诱导液,采用倒置显微镜、荧光显微镜及扫描电镜检测,并采用四氮唑蓝(MTT)比色法测定HA/TCP植骨材料上BMSCs的增殖情况。结果BMSCs在成骨诱导液中7d碱性磷酸酶呈强阳性,10d矿化结节染色呈橘红色;在成脂诱导液中,21d油红O染色呈阳性。BMSCs在HA/TCP植骨材料上孔隙周围及孔隙内生长良好并大量增殖。MTT分析结果显示,HA/TCP对BMSCs的体外增殖无抑制作用。结论BMSCs与HA/TCP植骨材料有良好的生物相容性。 相似文献
70.
Robert J. Clarke Beth W. Datskovsky Antony M. Grigonis E. Hazel Murphy 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,91(2):296-302
Summary In visual cortex of normal adult rabbits, callosal projections are restricted to a 2 mm wide band at the area 17/18 border. In adult rabbits which are monocularly enucleated (ME) on the day of birth, the callosal zone extends 4 mm into the medial region of area 17 in the cortex ipsilateral to the remaining eye. In this study, the function of these anomalous callosal projections in ME rabbits was investigated using electrophysiological techniques. A microelectrode was placed in the visual cortex ipsilateral to the enucleated eye at the 17/18 border, bipolar stimulating electrodes were placed in a homotopic location in the contralateral cortex, and averaged evoked responses (AERs) to stimulation were recorded. The stimulating electrodes were then moved mediolaterally in 1 mm steps, and the AERs were recorded for each location of the stimulating electrodes. In the normal rabbit, a maximal short latency evoked response was recorded when the stimulating electrodes were at a location homotopic to the recording electrode. When the stimulating electrodes were moved a distance of 1 mm or more from this optimal position, this short latency response was either absent or dramatically decreased in amplitude, reflecting the precise topographic pattern of the normal callosal projection. In contrast, in ME rabbits, a consistent response was evoked at the 17/18 border when the stimulating electrodes were moved as much as 3 mm medial to the homotopic position. Since antidromically activated responses and both pre- and post-synaptic orthodromically activated responses contribute to the AER, recordings were also made from single cells in some animals. Orthodromically activated single cell responses were evoked by electrical stimulation in the abnormal medial callosal zone of ME rabbits. The data indicate that abnormal callosal projections in ME rabbits can mediate functional interactions between nonhomotopic areas of the primary visual cortices. 相似文献