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2.
Summary The devastating neuropathological changes wrought by the intrathecal administration of vincristine are reported, with a detailed account of the widespread lesions in the brain and spinal cord, found in post-mortem light- and electron-microscope studies.  相似文献   
3.
Summary Goal of Surgery Stable internal fixation of extraarticular proximal humeral fractures. Indications Extraarticular fractures angulated more than 30° which can be reduced closely or through a small incision. Epiphysiolysis. Fracture-dislocation of the humeral head. Contraindications Pathological fractures. Four part fractures. Segmental fractures of the humerus. Positioning and Anaesthesia Supine; the affected shoulder overhanging the edge of the table and supported by a radiolucent board. General or regional anaesthesia. Surgical Technique Closed pinning of two part and certain three part fractures of the proximal humerus being displaced, unstable, and mainly at the metaphyseal level. Introduction of Kirschner wires through a diaphyseal window and advancement into the proximal fragments after reduction which is controlled by image intensification. Postoperative Management Temporary immobilization in a sling. Passive and active assisted movements after a few days. Active movements after 2 weeks. Removal of wires after 3 months. Possible Complications Fracture of the humerus at the site of the cortical window. Injury to the radial nerve. Results 32 patients, mean age 49 years, 30 two part fractures and 2 three part fractures. Number of Kirschner wires used: 3 to 6, mean 4. Two out of 3 patients complained of pain at the site of wire insertion. All fractures consolidated. No avascular necrosis nor infection. Complications: Partial loss of internal fixation in 3 patients. One fracture of the humeral shaft. Sympathetic reflex dystrophy in 3 patients. Half of the patients had a normal range of motion. Time of follow-up: 6 to 24 (mean 10) months. Division of Orthopaedics and Traumatology, Purpan Hospital, Toulouse, France.  相似文献   
4.
Summary Earlier studies using hot-film anemometry in pigs have revealed skewed tangentially rotating velocity profiles in the ascending aorta during systole. The reason for this phenomenon has been postulated to be caused by the left ventricular contraction pattern. Therefore, the aim of this study was to investigate the influence of the left ventricular contraction pattern on the velocity fields in the ascending aorta of pigs. We used a 10 MHz perivascular pulsed Doppler ultrasound system to measure point blood velocities at two axial locations over the entire cross sectional area in the ascending aorta of 90 kg pigs. The axial component of the velocity profiles was visualized dynamically by computerized 3-dimensional animation techniques. Changing left ventricular contraction patterns were accomplished by reversible occlusion of either the left anterior descending or right posterior descending coronary artery. The axial development of the systolic rotating and skewed velocity profiles in the ascending aorta was described. The appearance of the systolic velocity profiles were virtually unaffected by changes in left ventricular contraction pattern.This study was kindly supported by The Danish Heart Foundation, Civilingeniør Frode Nyegaard og Hustru's Fond and NOVO's Forskningsfond  相似文献   
5.
Summary The ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.Abbreviations used in Figures and Tables a nucleus accumbens - abl nucleus amygdaloideus basalis, pars lateralis - abm nucleus amygdaloideus basalis, pars medialis - ac nucleus amygdaloideus centralis - AC anterior cingulate area - al nucleus amygdaloideus lateralis - am nucleus amygdaloideus medialis - ar nucleus arcuatus - CC tractus corporis callosi - CSDV commissura supraoptica dorsalis, pars ventralis - DB diagonal band - DM nucleus dorsomedialis hypothalami - EP nucleus entopeduncularis - ha nucleus anterior hypothalami - hl nucleus lateralis hypothalami - hp nucleus posterior hypothalami - IL infralimbic area of frontal cortex - lh nucleus habenulae lateralis - LH1 medial forebrain bundle (MFB) at the level of commissura anterior - LH2 lateral preoptic area - LH3 MFB at the level of the nucleus anterior hypothalami - LH4 MFB at the level of the nucleus ventromedialis hypothalami - LH5 MFB at the level of the nucleus posterior hypothalami - MFB medial forebrain bundle - pf nucleus parafascicularis - PL prelimbic area of frontal cortex - pol nucleus preopticus lateralis - pom nucleus preopticus medialis - posc nucleus preopticus, pars suprachiasmatica - pt nucleus parataenialis - pv nucleus premamillaris ventralis - PV nucleus paraventricularis - pvs nucleus periventricularis stellatocellularis - pvr nucleus periventricularis rotundocellularis - SC sulcal cortex - SGPV substantia grisea periventricularis - SI substantia innominata - SL lateral septal nucleus - ST bed nucleus of stria terminalis - sum nucleus supramamillaris - TO tractus opticus - tmm nucleus medialis thalami, pars medialis - VM nucleus ventromedialis hypothalami The nomenclature used in this paper is according to König and Klippel's Stereotaxic Atlas (1967).  相似文献   
6.
Summary Branching neurons giving rise to ascending and descending collaterals were studied in the cervical spinal cord of the rat. After unilateral injection of two retrograde fluorescent tracers, i.e. DY.2HCl at T2 or more caudal levels and TB at C1 or more rostral levels, many DY-TB double-labeled neurons were found in C3 to C8. These neurons were located bilaterally throughout the spinal grey matter, as well as in the lateral spinal nucleus (LSN). However, no double-labeled neurons could be detected in the laminae I and II on either side. The double-labeled neurons must represent branching neurons giving rise to a collateral ascending to the rostral injection-site or above, and another collateral descending to the caudal injection-site or below. The descending collaterals were found to extend to various spinal levels, including the lumbosacral cord. However, most of them terminated at shorter distances from their parent cell bodies; thus 20% of the C3–C8 neurons projecting to C1 or above had a descending collateral reaching T2, 8% had a collateral reaching T9, and 3% a collateral reaching L2/L3. The ascending collaterals of the majority of the branching neurons passed into the most caudal part of the medulla oblongata, and about half of these collaterals reached the level of the rostral part of the inferior olive. In regard to the neurons located in the segments C5–C8, about 13% of those projecting to T2 or below distribute an ascending collateral restricted to C2–C4, while 29% of those had an ascending collateral to C1 or above.  相似文献   
7.
目的 :探讨带旋股外侧动脉升支阔筋膜张肌支髂骨瓣的解剖及应用要点。方法 :在 2 5侧经动脉灌注红色乳胶的成人下肢标本上 ,重点观测旋股外侧动脉升支阔筋膜张肌支的走行、分支、发出点和外径等。结果 :旋股外侧动脉升支的阔筋膜张肌支上行支发出点距髂前上棘平面 7.1± 2 .3cm ,外径 1.2± 0 .8mm ,该支又分出 2~ 3支外径在 0 .3mm~ 0 .5mm的小分支从阔筋膜张肌后份进入肌质 ,上行至肌起始处达髂骨 ;其下行支发出点距髂前上棘平面 7.9± 1.8cm ,外径 1.3± 0 .8mm。结论 :旋股外侧动脉升支阔筋膜张肌支髂骨瓣具有手术可行性和实际应用价值  相似文献   
8.
李想  柏树令  范军  王军  佟浩 《解剖学报》2008,39(6):941-943
目的 探讨明胶酶在升主动脉瘤形成过程中的活性变化及意义. 方法 将35只Wistar大鼠随机分为对照组和实验组.采用升主动脉缩窄鼠制备升主动脉瘤模型.于术后3~5个月取升主动脉,应用明胶酶谱分析及薄膜原位酶谱法检测动脉瘤明胶酶的活性改变. 结果 正常动脉壁外膜无或极少有明胶酶活性;动脉瘤壁的中膜与外膜明胶酶活性明显增强. 结论 明胶酶活性升高可能在升主动脉瘤形成过程中起重要作用.  相似文献   
9.
Summary Axons in the medial rectus (MR) subdivisions of the oculomotor nucleus were identified by horizontal rotation and by electrical stimulation of the vestibular nerves and abducens nuclei. Three types of axons (vestibular type I and II and abducens interneurons) were then injected intra-axonally with horseradish peroxidase (HRP). Each injected axon was reconstructed under the microscope in the frontal and horizontal planes and terminal arborization and boutons contacting with MR motoneurons were studied. The MR motoneurons were identified by retrograde uptake of HRP, HRP being injected in the MR muscle prior to the intra-axonal experiment.The main types of horizontal canal-related axons were as follows: (1) ATD-unilateral termination axons: Most type I axons were of this type. Axons ascended in ascending tract of Deiters (ATD) to the oculomotor nucleus and terminated in ipsilateral MR area. (2) ATD-bilateral termination axons: Very few secondary canal responsive axons were in this group. Axons ascended in ATD to the oculomotor nucleus and terminated in MR motoneuron areas bilaterally and in the Edinger-Westphal nucleus. (3) MLF-bilateral termination axons: Most type II neurons were in this group. Axons went up in the contralateral MLF and into both oculomotor nuclei. Their branches distributed to several motoneuron areas but only infrequently to the MR area; and to the Edinger-Westphal nucleus. (4) AB interneuron axons: Axons ascended in the MLF contralateral to cells of origin and terminated in the contralateral MR motoneuron area.Supported by USPHS Grant No. 06658  相似文献   
10.
Summary 1.Responses were recorded from 160 ascending tract cells in segments L4 to L6 of the spinal cord in chloralose anaesthetized, spinalized cats. The tract cells were identified by antidromic activation following stimulation of pathways in the lateral and ventral funiculi at the level of the spinal cord transection at the thoracolumbar junction. Axonal conduction velocities ranged from 9 to 114 m/s. 2. A sample of 152 of the neurones examined could be subdivided according to the distribution of their receptive fields into 49 cells activated just from receptors located in skin (s cells), 17 neurones excited by receptors in deep tissues (d cells), 15 units with a convergent input from receptors in skin and deep tissues (sd cells), and 25 neurones with a convergent input from the knee joint and either skin (sj cells), deep tissues (dj cells) or both (sdj cells). No receptive fields could be demonstrated for the remaining 46 neurones. 3. S and sj cells were found almost exclusively in the dorsal horn, whereas many d, sd, sdj and dj units were in the ventral horn. Almost all of the cells that lacked receptive fields were in the ventral horn or intermediate grey. 4. Ninety-one of 158 cells (56%) demonstrated no background activity. Of these, 43 cells (27%) lacked receptive fields. Many of the silent neurones were in the ventral horn, but some were in the dorsal horn. Of 25 cells having knee joint input, 18 (72%) had background activity. 5. All of the neurones that had a receptive field in the knee joint also had a convergent input from receptors in other tissues. In 3 cases, there was a receptive field in the skin over the foot (sj cells). For 16 cells, receptive fields included not only the knee joint but also skin and deep tissue (sdj cells). Usually, the cutaneous receptive field was near the knee joint, but sometimes it was remote, such as on the foot. The deep receptive fields were chiefly in the muscles of the thigh and/or leg. For 6 dj cells, the receptive fields included not only the knee joint but also deep fields like those of sdj cells. 6. Cutaneous receptive fields were classified as low threshold (cells excited best by innocuous intensities of mechanical stimulation), wide dynamic range (cells activated by weak mechanical stimuli, but the best responses were to noxious stimuli) or high threshold (innocuous stimuli had little effect, but noxious mechanical stimuli produced a vigorous discharge). Similarly, stimulation of the knee joint with weak mechanical stimuli could excite some neurones, while others could be activated by weak or strong articular stimuli but were excited best by noxious stimuli, and still other neurones were activated by knee joint stimuli only if the intensity was noxious. 7. In several instances, contralateral receptive fields were noted. These were generally in deep tissue or in the knee joint. 8. It was concluded that many of the responses to articular stimulation of the spinal cord ascending tract cells examined in this study could have been mediated by the fine afferent fibres that supply the knee joint. Although further work will be required to determine which particular ascending tracts transmit nociceptive information concerning the knee joint, it can be proposed that many of the responses demonstrated here were likely to play a role in either joint pain of in triggering responses associated with joint pain.  相似文献   
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