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排序方式: 共有4354条查询结果,搜索用时 31 毫秒
1.
目的探讨环化酶激活剂(前列腺素E1、腺苷及Zn^2+离子)对周围神经损伤后感觉神经元的保护作用.方法在大鼠坐骨神经夹毁模型术后21 d,取背根节用图像分析法观测前列腺素E1(PGE1)、腺苷(Ade)和高Zn^2+饲料(Zn^2+)对背根节细胞数、核偏心率及核等圆径的影响,并与人胎盘神经生长因子(hNGF)的作用相比较.结果NGF及环化酶激活剂组与夹毁对照组相比都能增进背根节细胞的存活和减轻核偏移(P<0.05);NGF组和高Zn^2+饲料组在背根节细胞存活数、核偏心率及核等圆径方面与假手术组无差别(P>0.05).结论PEG1、Ade及Zn^2+离子等环化酶激活剂对DRG神经元均有保护作用,其中Zn^2+离子的保护效应与NGF无差别. 相似文献
2.
J. Carleson P. Kogner I. Bileviciute E. Theodorsson A. Appelgren B. Appelgren S. Kopp N. Yousef T. Lundeberg 《Archives of oral biology》1997,42(12):869-876
Temporomandibular joint (TMJ) arthritis was induced in female Lewis rats by unilateral injection of a suspension of heat-killed Mycobacterium butyricum in paraffin oil into the TMJ. Control rats received paraffin oil by the same route. Arthritic and control rats were pretreated either with capsaicin or denervation of the mandibular branch of the trigeminal nerve. Tissues were collected for neuropeptide extraction and analysed by radioimmunoassay and reverse-phase high-performance liquid chromatography. In all groups, the levels of substance P- (SP), calcitonin gene-related peptide- (CGRP) and neuropeptide Y- (NPY) like immunoreactivity (LI) were higher in the trigeminal ganglia than in the TMJs. In control rats, capsaicin significantly lowered the levels of SP-LI in the trigeminal ganglia and TMJ, but not CGRP-LI and NPY-LI. In the arthritic rats, capsaicin pretreatment significantly lowered the SP-LI and CGRP-LI in the trigeminal ganglia and TMJ, but not the NPY-LI. In the trigeminal ganglia the unilateral denervation significantly lowered SP-LI in control rats, and in arthritic rats SP-LI and CGRP-LI. On the denervated side of the arthritic TMJ, NPY-LI, SP-LI and CGRP- LI were significantly lowered as compared to the arthritic control rats and to the contralateral side. In this rat model, pretreatment with capsaicin and surgical denervation decreased the neuropeptide content in the trigeminal ganglia and the TMJ. The results clearly demonstrate a close interaction between increased neuropeptide release from sensory and sympathetic neurones after induction of arthritis in the rat. 相似文献
3.
M. D. Taylor M. L. de Ceballos S. Rose P. N. Chong P. Jenner C. D. Marsden 《Journal of neural transmission (Vienna, Austria : 1996)》1991,3(2):99-108
Summary Aged common marmosets were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP; 0.5–2.0 mg/kg/week i.p.) for 16 or 24 weeks, observed for a total of 30 weeks and then killed for measurement of biochemical pramaters in basal ganglia. The MPTP treatment induced a marked depletion in dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid levels in the caudate nucleus and putamen. In contrast, the concentrations of five neuropeptides: [Met5]-enkephalin, [Leu5]-enkephalin, cholecystokinin, substance P and neurotensin as measured by a combined HPLC/RIA method, remained unaltered in all basal ganglia regions examined. Enkephalin precursor levels, as reflected by cryptic [Met5]-enkephalin content, were increased in the putamen, but not in the caudate nucleus, as a consequence of MPTP administration. Cryptic [Leu5]-enkephalin content remained unchanged in the striatum of MPTP treated marmosets. Overall, these results suggest an increase in striatal [Met5]-enkephalin release following chronic MPTP treatment of aged marmosets. However, the chronic treatment of aged marmosets with MPTP does not reproduce the neuropeptide alterations characteristic of Parkinson's disease. 相似文献
4.
SK&F 86466, 6-chloro-3-methyl-2,3,4,5-tetrahydro-1-H-3-benzazepine, is a potent and selective antagonist of the α2-adrenoceptor in vitro. This compound produced a small pressor response accompanied by a marked bradycardia when administered i.v. to the pithed normotensive rat. The pressor response was not affected by reserpine treatment, pretreatment with α- or β-adrenoceptor antagonists, atropine, or hexamethonium. The bradycardia was markedly reduced by bilateral vagotomy and pretreatment with atropine and attenuated by hexamethonium. The negative chronotropic action of SK&F 86466 was abolished by a combination of vagotomy and atropine. Mediation of the bradycardia by a baroreceptor reflex was ruled out by the observations that a lack of change in heart rate was associated with the vasopressor response to phenylephrine in the pithed rat pretreated with propranolol. It is concluded that the negative chronotropic action of SK&F 86466 in the pithed rat is mediated indirectly by activation of the cholinergic innervation of the heart. 相似文献
5.
Sofia I. Andrikoula Haris S. Vasiliadis Anastasios V. Tokis Paraskevi Kosta Anna Batistatou Anastasios D. Georgoulis 《Arthroscopy》2007
Intra-articular ganglia are rare and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. We present 4 cases of intra-articular ganglion cysts associated with the anterior cruciate ligament (ACL) in 3 patients. The most commonly occurring symptoms were pain aggravated after stressing activities and limited knee range of motion. In 1 patient, ganglion cysts appeared in both knees with a time difference of 1 year. An MRI revealed typical signs of ganglion cysts in the substance of the ACL. Arthroscopy was performed for further evaluation and treatment. Histologic examination of the tissue removed revealed the presence of features consistent with ganglion cysts. Therefore, in the case of chronic knee discomfort with nonspecific clinical signs and symptoms and without a clear cause, an intra-articular ganglion cyst should be considered as causing pathology. An MRI is the most sensitive and specific method for diagnosis. However, the relatively slow progression of symptoms may delay the patient’s decision to seek medical attention. Delayed diagnosis makes arthroscopic total resection of the ganglion technically demanding or not possible at all, and extensive debridement of the ACL may be required. 相似文献
6.
Nelson Wolosker Guilherme Yazbek José Ribas Milanez de Campos Paulo Kauffman Augusto Ishy Pedro Puech-Leão 《Clinical autonomic research》2007,17(3):172-176
Background Sympathectomy is the treatment of choice for primary hyperhidrosis. One curious occurrence that is difficult to explain from
an anatomophysiological point of view in cases of video-assisted thoracoscopic sympathectomy (VATS) for the treatment of palmar
hyperhidrosis (PH) is the observed improvement in plantar hyperhidrosis (PLH). Nevertheless, current reports on VATS rarely
describe the effect on PLH or just give superficial data. The aim of this study was to prospectively investigate, how surgery
affects PLH in patients with PH and PLH over one-year period.
Methods From May 2003 to January 2004, 70 consecutive patients with combined PH and PLH underwent VATS at the T2, T3, or T4 ganglion
level (47 women and 23 men, with mean age of 23 years).
Results Immediately after the operation, all the patients said they were free from PH episodes, except for two patients (2.8%) who
suffered from continued PH. Compensatory hyperhidrosis (CH) of various degrees was observed in 58 (90.6%) patients after one
year. Only 13 (20.3%) suffered from severe CH. There was a great initial improvement in PLH in 50% of the cases, followed
by progressive regression, such that only 23.4% still presented that improvement after one year. The number of cases without
overall improvement increased progressively (from 17.1% to 37.5%) and the numbers with slight improvement remained stable
(32.9–39.1%). Of the 24 patients with no improvement after one year, 6 patients graded plantar sweating worse.
Conclusion Patients with PH and PLH who undergo VATS to treat their PH present a good initial improvement in PLH that reduces to a lower
level of improvement after the one-year period. 相似文献
7.
Summary A review is made of the current management strategies of abscesses in basal ganglia and thalamus, based on a review of the literature and three of our own cases. Clinical picture, aetiology, diagnostic, surgical treatment and outcome are discussed. Stereotactic abscess puncture in combination with temporary drainage and rinsing of the abscess cavity in combination with systemic medication of antibiotics has become the management of choice with satisfactory results. 相似文献
8.
M. Fujioka K. Okuchi S. Miyamoto T. Sakaki K. Hiramatsu M. Tominaga Y. Kamada S. Iwasaki 《Neuroradiology》1994,36(8):605-607
We report specific changes bilaterally in the basal ganglia and thalamus following reperfusion after complete cerebral ischaemia. A 69-year-old man, resuscitated after cardiac arrest, showed symmetrical lowdensity lesions in the head of the caudate nucleus and lentiform nucleus on CT. MRI revealed methaemoglobin derived from minor haemorrhage in the basal ganglia and thalamus, not evident on CT. We suggest that this haemorrhage results from diapedesis of red blood cells through the damaged capillary endothelium following reperfusion. 相似文献
9.
We present two case studies, one of generalized chorea and one of hemichorea, both after severe hypoglycemia episodes. Both cases showed hyperperfusion in their SPECT scans. The MRI and SPECT findings serve as clues regarding the role of basal ganglion dysfunction associated with chorea. 相似文献
10.
M. Wiegand A. A. Möller C. J. Lauer S. Stolz W. Schreiber M. Dose J. C. Krieg 《Journal of neurology》1991,238(4):203-208
Summary Nocturnal sleep was studied in 16 inpatients with Huntington's disease. In comparison with healthy controls, patients exhibited a disturbed sleep pattern with increased sleep onset latency, reduced sleep efficiency, frequent nocturnal awakenings, more time spent awake and less slow wave sleep. These abnormalities correlated in part with duration of illness, severity of clinical symptoms, and degree of atrophy of the caudate nucleus. Patients showed an increased density of sleep spindles. 相似文献