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21.
C. H. Yeo M. J. Hardiman M. Glickstein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,60(1):114-126
Summary We report the connections of cerebellar cortical lobule HVI in the rabbit. We have studied the anterograde and retrograde transport of wheatgerm-agglutinated horseradish peroxidase (WGA-HRP) following its injection into HVI to reveal efferent and afferent connections. All of the cases showed strong anterograde transport to the anterior interpositus nucleus (AIP) — indicating that this is the major efferent target of HVI. Retrogradely labelled cells were found in the inferior olivary, spinal trigeminal, lateral reticular, inferior vestibular and pontine nuclei. Within the olive, the medial part of the rostral dorsal accessory olive (DAO) and the adjacent medial part of the principal olive (PO) were consistently labelled in all cases. This area is known to receive somatosensory information from the face and neck. There was no projection to the hemispheral part of lobule VI from visual parts of the olive within the dorsal cap and medial parts of the medial accessory olive. Likely sources of visual and auditory information to HVI are the dorsolateral basilar pontine nuclei and nucleus reticularis tegmenti pontis, which were densely labelled in all cases. These anatomical findings are consistent whith the suggestion that, during NMR conditioning, information related to the periorbital shock unconditional stimulus (US) may be provided by climbing fibres to HVI and light and white noise conditional stimulus (CS) information may be supplied by pontine mossy fibres. 相似文献
22.
布氏显微镜活血分析: 细胞流变学研究的新方法 总被引:14,自引:0,他引:14
布氏显微镜活血分析:细胞流变学研究的新方法骆秉铨*黄荣国*陈兴新*细胞流变学是研究血细胞流动变形的科学,在方法学上发展了一些比较成熟的方法,但多不能直接动态观察细胞水平的真实改变,有待完善和创新。我们采用布氏多功能显微镜的活血分析法[1],在高放大倍... 相似文献
23.
脑动脉DSA形态分析及其意义 总被引:3,自引:0,他引:3
目的:探讨脑血管造影各主要动脉的投影规律及其分支的显示率,为脑血管疾病的影像诊断和介入治疗提供重要参考。方法:随机抽取140例全脑血管DSA系列图像,选择其中无脑血管疾病的51例进行观察。分别统计颈内动脉和椎动脉造影时正常脑血管各主要分支的显示率;归纳大脑前动脉A1段、大脑中动脉M1段及大脑后动脉P1段在平面上的投影规律并分析总结了脑动脉的正常解剖学特征及其变异。结果:①脑底动脉变异较大;②颈内动脉照影时OA、AChA、ACoA、PCoA、ACA和MCA的显示率分别为96.1%、92.2%、52.9%、69.6%、100%和100%;③椎动脉造影时PICA、AICA、BA、SCA、PCA和PCoA的显示率分别为66.7%、62.7%、100%、70.6%、80.4%和41.2%。结论:①尽管脑底血管实际解剖关系较为复杂,但造影时反映到平面上可简捷的用“水平、上升、下降”等来描述血管的形态和走行;②虽然是平面图像,通过调整投照体位仍可非常逼真的反映血流的动态变化。 相似文献
24.
B E Reese 《The Journal of comparative neurology》1986,250(1):8-32
The topographic organization of the uncrossed retinal projections to the dorsal lateral geniculate nucleus (dLGN) and superior colliculus (SC) was studied in normal adult hooded rats and in rats subjected to unilateral ocular enucleation on the day of birth. Sections were stained for anterograde degeneration products following discrete retinal lesions at various locations. The projection from the temporal crescent to the dLGN in neonatally enucleated rats had an expanded but topographically normal organization, with the nasotemporal and dorsoventral retinal axes displaying polarities identical to those in normal adults. Neonatal enucleation permits the remaining uncrossed retinogeniculate projection to extend primarily along the "lines of projection" into neuropil normally recipient of binocularly conjugate crossed projections. In the SC, the dorsoventral axis of the temporal crescent showed a normal polarity, but the nasotemporal axis failed to display any topographic organization. Retinal loci in the temporal crescent projected throughout the rostrocaudal extent of the ipsilateral SC. Retinal lesions placed outside the temporal crescent failed to produce any substantial degeneration in ipsilateral dLGN or SC. These topographically distinct effects in dLGN and SC following unilateral eye removal on the day of birth are discussed in the context of differing constraints upon axonal ingrowth and connectivity during early development, which may normally bring about the characteristically distinct features of retinogeniculate and retinocollicular organization. 相似文献
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Naturally occurring cell loss in the retinal ganglion cell population of one eye can be interrupted by removal of the other eye in newborn rodents. Many of the rescued retinal ganglion cells which project ipsilaterally reside in the nasal retina, that part of the retina normally giving rise to primarily crossed optic axons. Their naturally occurring elimination has been attributed to their hypothesized late neurogenesis and the consequent delayed time of arrival of their axons in the target visual nuclei, thereby placing them at a competitive disadvantage with other, early arriving, optic axons. By combining the technique of tritiated thymidine autoradiography with the retrograde axonal transport of horseradish peroxidase in rats that had been enucleated on the day of birth, we report here that rescued cells in the nasal retina which project ipsilaterally are generated at the same time as their neighbours in the temporal retina. Time of genesis does not distinguish them; consequently, their axons should not differ in their arrival times within the target visual nuclei. Since their only obvious anomaly is one of pathway choice at the optic chiasm, their place of arrival, rather than their time, may ultimately determine their naturally occurring elimination. 相似文献
28.
The present paper is the long-term conclusion of our preliminary presentation at the 1992 ISAPS Congress (Guadalajara, Mexico).
This is the result of 29 cadaver dissections of different ages and both sexes. We have observed that length, thickness, and
resistance correlate with the possibility to project the nasal tip with the mere structure of the alar cartilage and its medial
crurae. We also demonstrated the existence and antagonistic action of Pitanguy's ligament as well as the depressing ligament
to project the nasal tip. In this study, besides focusing on classifying the medial crus according to its thickness, length,
and resistance, which is already different from any previous classification, we also focused on its surgical utility, and
its interaction with other anatomic elements, to achieve the desired projection. Clinically, we present a 12-year experience
with 1653 cases operated under this premise. 相似文献
29.
Conzelmann S Levai O Bode B Eisel U Raming K Breer H Strotmann J 《The European journal of neuroscience》2000,12(11):3926-3934
Three novel G-protein-coupled receptor genes related to the previously described RA1c gene have been isolated from the mouse genome. Expression of these genes has been detected in distinct areas of the brain and also in the olfactory epithelium of the nose. Developmental studies revealed a differential onset of expression: in the brain at embryonic stage 17, in the olfactory system at stage E12. In order to determine which cell type in the olfactory epithelium expresses this unique receptor type, a transgenic approach was employed which allowed a coexpression of histological markers together with the receptor and thus visualization of the appropriate cell population. It was found that the receptor-expressing cells were located very close to the basal membrane of the epithelium; however, the cells extended a dendritic process to the epithelial surface and their axons projected into the main olfactory bulb where they converged onto two or three glomeruli in the dorsal and posterior region of the bulb. Thus, these data provide evidence that this unique type of receptor is expressed in mature olfactory neurons and suggests that it may be involved in the detection of special odour molecules. 相似文献
30.
Chuluunbaatar Otgonbaatar Jae-Kyun Ryu Jaemin Shin Ji Young Woo Jung Wook Seo Hackjoon Shim Dae Hyun Hwang 《Korean journal of radiology》2022,23(11):1044
ObjectiveThis study aimed to investigate whether a deep learning reconstruction (DLR) method improves the image quality, stent evaluation, and visibility of the valve apparatus in coronary computed tomography angiography (CCTA) when compared with filtered back projection (FBP) and hybrid iterative reconstruction (IR) methods.Materials and MethodsCCTA images of 51 patients (mean age ± standard deviation [SD], 63.9 ± 9.8 years, 36 male) who underwent examination at a single institution were reconstructed using DLR, FBP, and hybrid IR methods and reviewed. CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and stent evaluation, including 10%–90% edge rise slope (ERS) and 10%–90% edge rise distance (ERD), were measured. Quantitative data are summarized as the mean ± SD. The subjective visual scores (1 for worst -5 for best) of the images were obtained for the following: overall image quality, image noise, and appearance of stent, vessel, and aortic and tricuspid valve apparatus (annulus, leaflets, papillary muscles, and chordae tendineae). These parameters were compared between the DLR, FBP, and hybrid IR methods.ResultsDLR provided higher Hounsfield unit (HU) values in the aorta and similar attenuation in the fat and muscle compared with FBP and hybrid IR. The image noise in HU was significantly lower in DLR (12.6 ± 2.2) than in hybrid IR (24.2 ± 3.0) and FBP (54.2 ± 9.5) (p < 0.001). The SNR and CNR were significantly higher in the DLR group than in the FBP and hybrid IR groups (p < 0.001). In the coronary stent, the mean value of ERS was significantly higher in DLR (1260.4 ± 242.5 HU/mm) than that of FBP (801.9 ± 170.7 HU/mm) and hybrid IR (641.9 ± 112.0 HU/mm). The mean value of ERD was measured as 0.8 ± 0.1 mm for DLR while it was 1.1 ± 0.2 mm for FBP and 1.1 ± 0.2 mm for hybrid IR. The subjective visual scores were higher in the DLR than in the images reconstructed with FBP and hybrid IR.ConclusionDLR reconstruction provided better images than FBP and hybrid IR reconstruction. 相似文献