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31.
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
32.
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
33.
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
34.
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
35.
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
36.
37.
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
38.
逆行肝切除治疗难切性肝癌244例报道 总被引:3,自引:0,他引:3
目的 逆行肝切除是治疗难切性肝癌的有效方法 ,本文报道了 2 44例临床经验。方法 常规肝切除方法切除困难的 2 44例巨大、显露困难或下腔静脉受累的肝癌采用逆行切肝法结合血管外科技术予以切除 (A组 ) ,同期临床特征类似的 31例肝癌采用常规切肝法切除 ,作为对照 (B组 )。结果 两组均无手术死亡 ,A组与B组相比 ,术中出血量较少 ( 12 90± 998ml比 2 2 86± 136 3ml)、术后胸水发生率 ( 2 6 /2 44比 10 /31)、腹水发生率 ( 72 /2 44比 19/31)、中度到重度黄疸率 ( 14 /2 44比 5 /31)、手术区积液率 ( 17/2 44比 7/31)、膈下感染率 ( 3/2 44比 1/31)、胆漏发生率 ( 2 /2 44比 1/31)、切口感染率 ( 3/2 44比 1/31)以及ALT恢复时间 ( 13.8± 5 .1天比 18.9± 8.9天 )均较低 ,差别具有统计学意义 (P <0 .0 1)。结论 对于难切性肝癌而言 ,逆行肝切除是安全有效的手术方法。 相似文献
39.
Frequency of pancreatitis after endoscopic retrograde cholangiopancreatography with iopromid or iotrolan: a randomized trial 总被引:1,自引:0,他引:1
Blood isotone contrast media is considered to be less toxic to vascular and pancreatic duct endothelium than high-osmolar
contrast media. In this study we assessed the impact of a low-osmolar contrast agent compared with a blood isotone product
on pancreatic damage induced by endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic retrograde sphincterotomy
(EST). In a prospective trial 42 consecutive ERCP/EST patients were randomized to receive either iopromid, a low-osmolar non-ionic
contrast agent (770 mosmol/kg H2O), or iotrolan, a blood-isotone non-ionic product (320 mosmol/kg H2O). The endoscopies were performed by two experienced endoscopists. Forty patients were included in the study. Blood samples
were collected before and 40 min, 2, 4, 6 and 24 h after the endoscopic procedure. Samples were analysed for pancreatic serum
enzymes, acute-phase proteins and blood counts. A clinical pain score was investigated. Post-ERCP pancreatitis was diagnosed
in 2 patients in the iopromid group and in 5 patients in the iotrolan group. There was no significant difference between groups
in the time course of pancreatic serum enzymes, acute-phase proteins or in the pain score. Due to the small number of patients
in this study, only stronger differences caused by the two contrast media could have led to statistically significant results.
We did not observe statistically significant differences in comparing iotrolan and iopromid concerning ERCP/EST-induced pancreatic
damage.
Received: 26 February 1999; Revised: 14 May 1999; Accepted: 9 June 1999 相似文献
40.
Grisi G Stacul F Cuttin R Rimondini A Meduri S Dalla Palma L 《European radiology》2000,10(10):1620-1627
The aim of this study was to analyse the costs of different diagnostic approaches to patients with acute flank pain. Four
different diagnostic approaches were considered: (a) spiral CT without contrast medium (CM); (b) plain film, ultrasonography
(US) and intravenous urography (IVU) – the latter procedure is used in our department in cases still unsolved following the
former investigations (28 % in our experience); (c) plain film, US and spiral CT without CM (as an alternative to IVU in 28
% of cases); and (d) IVU. The cost of each procedure in a university hospital was calculated, following analysis of the differential
costs of each investigation (equipment, depreciation and maintenance costs, related materials and services, radiologists,
radiographers, nurses) and their common costs (auxiliary personnel and indirect internal costs). Finally, we calculated the
full cost of each procedure and applied it to the different diagnostic approaches. The full cost of each approach was: (a)
spiral CT without CM = 74 Euro; (b) plain film, US and IVU (28 %) = 66.89 Euro; (c) plain film, US and spiral CT without CM
(28 %) = 64.93 Euro; (d) IVU = 80.90 Euro. Intravenous urography alone or in unsolved cases is not to be considered because
it provides higher costs and worse diagnostic results, whereas X-ray dose to patient is almost equal between IVU and spiral
CT. Spiral CT integrated to plain film and US in unsolved cases could be preferred because of lower cost and dose to patient,
though reaching a diagnostic conclusion may take longer than an immediate spiral CT.
Received: 29 February 2000; Revised: 22 May 2000; Accepted: 23 May 2000 相似文献