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41.
以骨间背侧动脉为蒂逆行岛状皮瓣的应用解剖学 总被引:10,自引:2,他引:10
在60侧灌注血管染料的新鲜成人上肢标本上,观察了骨间背侧血管在前臂背侧的起点、走行和分支,发现该动脉终末支在腕上2.5cm 水平,与骨间掌侧动脉背侧支之间有恒定的吻合支相连,并以此吻合支为蒂,设计了前臂骨间背侧血管逆行岛状皮瓣。 相似文献
42.
目的探讨囊肿切除、胆道重建治疗婴儿胆总管囊肿的疗效.方法1984年6月~1999年6月共有15例婴儿先天性胆总管囊肿患儿在我科接受了囊肿切除、胆道重建手术治疗,并对这些患儿进行了随访,随访资料包括症状、体征、B超.钡餐及肝功能检查.结果随访资料完整者12例,除1例术后3个月死于肝功能衰竭外,其余11例成活的患儿生长发育均正常;2例未行套叠瓣的患儿偶有上腹疼痛,但腹痛可自行缓解,钡餐检查见钡剂返流;全组病例肝功均正常,未见胆道结石、消化道溃疡、食道下端静脉曲张.结论囊肿切除、胆道重建治疗婴儿先天性胆总管囊肿可取得满意的疗效. 相似文献
43.
目的:探讨先天性胆管囊肿的病因、分型、诊断和治疗方法。方法:回顾1986至1996年10年间收治的先天性胆管囊肿28例进行分析。结果:28例中Ⅰ型19例(6785%),IVA型8例(286%),IVB型1例(36%)。B超检查26例,24例手术证实;CT9例7例手术证实。手术治疗为最佳手段,以囊肿切除为首选。本组25例手术治疗,囊肿切除13例(占52%)。结论:B超为主要诊断手段。先天性胆管囊肿癌变率随病程延长而逐渐上升,故切除囊肿为首选治疗手段 相似文献
44.
The possibility of a direct projection from the perirhinal cortex (PER) to areas CA1 and subiculum (SUB) in the hippocampus has been suggested on the basis of tracer studies, but this projection has not unequivocally been supported by physiological studies. The demonstration of such a functional pathway might be important to understand the functioning of the hippocampal memory system. Here we present physiological and further anatomical evidence for such a connection between PER and the hippocampus. Electrical stimulation of PER in vivo evoked field potentials (EFPs) at the border area of CA1/SUB, consisting of a short latency and a longer latency component. Current source density analysis revealed that the sink of the short latency component was situated in the molecular layer of area CA1/SUB, while the longer latency component had its sink in the outer molecular layer of the dentate gyrus (DG). Anterograde tracer injections in PER showed labelled fibres in the border area of CA1/SUB, but anatomical evidence for a projection of PER to DG was not found. When synaptic transmission in the entorhinal cortex was partly blocked, the amplitude of the longer latency component of the recorded EFPs in the hippocampus was decreased while the short latency component was not affected, which suggests that the indirect pathway originating in PER is mediated through a synaptic relay in the entorhinal cortex. From the present results we conclude that information originating in PER reaches area CA1/SUB by parallel, direct and indirect, routes. The existence of this parallel organization appears to form an essential feature for the proper function of the medial temporal lobe memory system. 相似文献
45.
The consequence of neonatal eye removal on the adult organization of the geniculo-cortical pathway was studied anatomically in hamsters. Separate discrete injections of rhodamine- and green-fluorescent latex microspheres were made into the primary visual cortex of adult hamsters. The distribution of labelling in the dorsal lateral geniculate nucleus (dLGN) of normal animals was compared with that seen in animals monocularly enucleated at birth. In the normal animals, as expected, the projection has a precise topographic order. This is also true of the projection contralateral to the remaining eye in the enucleated animals. However, on the side ipsilateral to the remaining eye, the visual cortex appears to receive two convergent projections from the deafferented dLGN, one mirroring the other. A single injection made in very lateral cortex labels cells in two discrete regions of the dLGN. As the injection is made progressively more medial, the two patches of labelled cells converge. Eventually, the two patches are no longer discrete so that injections into central area 17 produce just one, extended patch of labelling. These results suggest that the altered retinal input to the dLGN may affect the subsequent development of ordered geniculo-cortical projections. 相似文献
46.
Menétrey D De Pommery J Thomasset M Baimbridge KG 《The European journal of neuroscience》1992,4(1):70-76
This study concerns the involvement of calbindin-D28K (CaBP28k)-containing neurons in ascending spinal projections to the brainstem (nucleus of the solitary tract, lateral reticular nucleus area), pontine (parabrachial area) and mesencephalic (periaqueductal grey) structures. All these central structures are important in the processing of visceroception and visceronociception and all are targets for spinal efferents from similar areas. CaBP28k controls the excitability of cells by acting on intrinsic calcium metabolism. Results refer to the caudal spinal areas where the visceroceptive regions are concentrated. Experiments were performed through a double labelling approach that combined the retrograde transport of a protein - gold complex to identify the projection cells and immunohistochemistry to identify the CaBP28k-positive cells. The caudal spinal cord is rich in both CaBP28k-containing and projection cells. Cells colocalizing the protein and the retrograde tracer were quite numerous, with a particularly high concentration in the superficial layers of the dorsal horn (laminae I and outer II) and the lateral spinal nucleus. The other spinal areas containing immunoreactive projection cells were the reticular part of the neck of the dorsal horn, the medial laminae VII and VIII, lamina X and the sacral parasympathetic nucleus. The superficial layers and the neck of the dorsal horn are targets for nociceptive, visceroceptive and thermal inputs; the sacral parasympathetic column and lamina X are involved in visceroceptive integration. A functional role for the lateral spinal nucleus has not yet been established. Quite similar results were obtained for each of the ascending pathways under study. The high incidence of CaBP28k in spinal pathways suggests that calbindin has a major role in controlling the excitability of spinal cells subserving the processing of visceroception and/or visceronociception information to supraspinal levels. The participation of CaBP28k-immunoreactive cells in spinal ascending tract cells largely outnumbers those previously reported for various neuropeptides (Leah et al., Neuroscience, 24, 195 - 207, 1988) 相似文献
47.
Stephen C. Nicholls MD Theodore C. Koutlas MD D. Eugene Strandness MD 《Annals of vascular surgery》1991,5(4):331-336
Although retrograde vertebral artery flow was described over 100 years ago, its relationship to symptoms remains unclear. We documented 43 patients who were found by duplex scanning to have reverse flow in the vertebral artery. Of this group, seven patients (16%) were found to have symptoms described as typical for the subclavian steal syndrome. Nearly one-third were asymptomatic. Of the remaining patients, 13 (30%) presented with nonhemispheric symptoms while nine (21%) had hemispheric symptoms. Nine patients had to and fro flow in the vertebral artery. This variant was not found in subclavian steal patients but correlated with nonhemispheric symptoms. During follow-up (mean: 19 months) none of the asymptomatic patients became symptomatic, and there were no strokes or stroke-related deaths. Surgical procedures which restored antegrade vertebral artery flow did not necessarily improve symptoms of posterior circulation ischemia. In some patients improvement in posterior circulation symptoms was noted following carotid endarterectomy. It is concluded that retrograde flow in the vertebral artery is, per se, a benign entity. Accurate selection of surgical candidates remains imprecise. It will require not only identification of vertebrobasilar disease but as yet undefined tests to assure symptoms are due to these stenoses. 相似文献
48.
49.
Using classical neuroanatomical retrograde tracing methods we investigated the retinal ganglion cells projecting to the nucleus of the optic tract and dorsal terminal nucleus of the accessory optic system (NOT-DTN) in macaque monkeys. Our main aim was to quantify the strength of the projection from the ipsilateral retina to the NOT-DTN. We therefore examined the number, distribution, and soma size of retinal ganglion cells involved in this projection. Electrophysiologically controlled small injections into the NOT-DTN revealed a clearly bilateral retinal projection originating mainly from the central retina but also involving peripheral retinal regions. Labelled cells were found nasally in the contralateral retina and temporally in the ipsilateral retina with some overlap in the fovea. The projection from the ipsilateral retina was 36-43% of that from the contralateral retina. On average, only 1-6% of the local population of ganglion cells projected to the NOT-DTN. Small soma size and large dendritic fields imply that in monkey rarely encountered, 'specialized' ganglion cells provide the direct retinal input to the accessory optic system (AOS). These results are discussed with respect to the symmetry of monocular horizontal optokinetic nystagmus (OKN) in primates. 相似文献
50.
First experience with gamma probe guided sentinel lymph node surgery in penile cancer 总被引:3,自引:0,他引:3
Wawroschek F Vogt H Bachter D Weckermann D Hamm M Harzmann R 《Urological research》2000,28(4):246-249
Because of the curative approach, the detection of lymph node metastases in squamous cell carcinoma (SCC) of the penis is
of significant clinical relevance. Sentinel lymph node (SLN) identification by means of lymphangiography has been proven to
be insufficiently safe. However, the high morbidity of inguinal lymphadenectomy and the considerable individual variability
regarding the location of lymph node metastases justify the necessity of a technique that enables the identification of SLNs.
Since 1998, SLNs have been intraoperatively identified and selectively dissected, after peritumoral injection of technetium-99m
nanocolloid and using lymphoscintigraphy, in three patients (one with malignant melanoma and two with SCC). At least one SLN
could be detected in each patient. The maximum surgical time was 30 min. There were no severe complications. Lymph node metastases
did not occur in any patient. Upon a mean follow-up of 10 months, all patients are currently free of tumor. Owing to the long-term
results of sentinel lymphadenectomy in malignant melanoma of other locations and our preliminary results with respect to penile
carcinoma, we consider the current method appropriate as the only primary operation for lymph node staging in early stages
and, in combination with modified inguinal lymphadenectomy, in locally advanced stages.
Received: 24 November 1999 / Accepted: 21 April 2000 相似文献