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71.
The effect of various immunomodulators on the induction of experimental autoimmune encephalomyelitis (EAE) is evaluated in the Lewis rat. Bordetella pertussis (BP) is the optimal inductor of EAE in this rat strain. Treatment of the animals with BP either before or after or simultaneously with guinea-pig spinal cord preparation (GpSC) resulted in an EAE about two weeks thereafter. Additional injection of living BCG, of CFA, IFA (incomplete Freund's adjuvant) or Vibrio cholerae neuraminidase (VCN) did not augment or mitigate the effect induced by BP or GpSC. Living BCG, IFA, VCN or Corynebacterium parvum (CP) did not induce EAE when given in combination with GpSC but without BP. CFA combined with GpSC only occasionally induced EAE. However, EAE could be induced by the combination of CFA and GpSC or IFA and GpSC in a part of the animals tested if they had been pretreated or simultaneously been injected with living BCG by intravenous route. EAE could not be enhanced by the additional injection of VCN. Surprisingly, most of the animals peracutely died after injection of CFA and BP in combination with GpSC when they had been pretreated with CP. This effect was most pronounced when pretreatment was done on day -4. No acute effect could be seen when CP was given simultaneously to CFA, BP and GpSC. Animals which did not peracutely succumb developed EAE similarly as those in the positive control groups. CP treatment simultaneously with BP but without CFA resulted in a reduction of the EAE specific mortality. This reduction could not be seen if treatment with CP was done after injection of GpSC and BP.  相似文献   
72.
We describe clinical and genetic data from the study of two families with 80 members affected with the autosomal dominant, slowly progressive spinal muscular atrophy of late onset (average 48.8 years), first described by Finkel in 1962. Electromyography and muscle biopsy of a number of patients confirmed the neurogenic nature of the condition. Unusual findings in this disorder were cramps, spontaneous fits of suffocation, and symptomatic myotonia. Other manifestations are slow loss of muscle strength and progressive proximal atrophy, which starts in the lower limbs and progresses to the upper limbs; hypoactive or absent tendinous reflexes; and generalized fasciculations. Sensory and cranial nerve function is unimpaired. Probabilities for genetic counseling are evaluated by means of a method adequate to the late-onset nature of the condition.  相似文献   
73.
采用HRP追踪法,对成年大鼠膈神经运动纤维的起源和初级传入神经元胞体的位置及在其中枢突脊髓的投射进行了观察。结果表明,膈神经运动纤维在脊髓标记(膈核)主要分布在注射侧C_3-C_5脊髓节段的前角。隔神经感觉纤维初级传入标记的神经元见于注射侧C_3-C_6后根节,其中C_4标记的细胞数最多。  相似文献   
74.
Summary Two cases of quadriceps amyotrophy, probably of chronic neurogenic origin are reported. Only the knee jerks were diminished, the calves hypertrophic, and the serum creatine kinase level very high in one case, and there were neurogenic electromyographic abnormalities in the quadriceps. In the first case, biopsy of the quadriceps muscle revealed a neurogenic origin with hyalinized hypertrophic fibres. CT scan showed abnormalities not only in the quadriceps but also in the sartorius, gracilis and gastrocnemius muscles. A second biopsy specimen from the gastrocnemius muscle showed histological findings similar to those of the quadriceps. In the second case, the EMG and biopsy findings suggested a myogenic origin, but 6 years later they were compatible with neurogenic atrophy. Differentiation from Becker dystrophy is very difficult in the first case and the second case is more a focal spinal amyotrophy. Further, in spite of their localization, the extension of the affected muscles changes the diagnosis. The same applies to chronic quadriceps amyotrophy in general, which cannot be regarded as an entity, but which suggests muscular dystrophy, spinal atrophy, polymyositis or a metabolic disorder. These cases can be compared with the four cases reported in the literature, which were regarded as a forme fruste of chronic spinal amyotrophy.  相似文献   
75.
Summary Groups of male rats were treated for a period of 14 days with imipramine (10mol/kg) given twice daily. Separate groups of rats received a single dose treatment using the same dose and experimental design as for the repeated treatment. Employing the avidin-biotin immunoperoxidase technique for immunohistochemistry 5-hydroxytryptamine (5-HT)-, substance P (SP)- and thyrotropin releasing hormone (TRH)-like immunoreactivities (IRs) were visualized in consecutive coronal sections of the brain stem and of the spinal cord. The IRs were studied by means of morphometric and microdensitometric procedures using automatic image analysis on profiles representing nerve terminal networks of the ventral horn of the cervical and lumbar enlargements of the spinal cord as well as their coexistence (5-HT/SP and 5-HT/TRH). With the same technique 5-HT IR was measured in the 5-HT nerve cell groups of the medulla oblongata (B 1, B 2, B 3) and of the nucleus raphe dorsalis (B 7) of the midbrain. In addition 5-HT and 5-hydroxyindolacetic acid (5-HIAA) levels were measured in the ventral and dorsal horns of the cervical and lumbar enlargements of the spinal cord using high performance liquid chromatography (HPLC). In the same parts of the spinal cord SP IR was studied by means of radioimmunoassay (RIA).The microdensitometric studies showed that chronic, but not acute, imipramine treatment selectively increased SP IR in the 5-HT/SP/TRH costoring nerve terminals of the medial part of the ventral horn in both the cervical and the lumbar enlargements. Furthermore, quantitative analysis of the entity of coexistence in the 5-HT nerve terminal networks of these areas showed that all the 5-HT nerve terminals contained SP and TRH IRs and that this phenomenon remained after acute and chronic imipramine treatment. The microdensitometric studies on the 5-HT nerve cell groups of the medulla oblongata and of the nucleus raphe dorsalis demonstrated that chronic, but not acute, imipramine treatment selectively increased 5-HT IR in the nerve cell bodies of the lateral part of group B 3 as evaluated from the median grey values. Acute, but not chronic, imipramine treatment significantly increased the field area of 5-HT IR of nerve cell bodies in group B 7, reflecting an increase in the mean profile area of the 5-HT IR nerve cell body profiles. Instead, the mean profile area of 5-HT IR cell bodies of group B 1 was acutely reduced by imipramine.The biochemical studies demonstrated that chronic imipramine treatment selectively reduced 5-HT utilization in the ventral horn of the spinal cord and selectively increased SP IR in the dorsal horn of the lumbar enlargement.In view of these observations it is suggested that chronic imipramine treatment specifically increases SP IR in the 5-HT/SP/TRH costoring nerve terminals of the ventral horn probably related to reduced SP release and reduced 5-HT utilization in these terminals. The results obtained in group B 7 may be explained by a regulation by the3H-imipramine raphe binding sites of fast axonal transport, an influence which may have therapeutic consequences. This mechanism may also be responsible for the increase in 5-HT IR seen upon chronic imipramine treatment in the lateral part of the 5-HT nerve cell body group B 3. Such an effect may lead to a metabolic down-regulation of group B 7, having a possible role for the antidepressant activity of imipramine. The reduction of the mean profile area of 5-HT IR cell bodies of group B 1 seen in the acute treatment can possibly be caused by, noradrenaline (NA) uptake inhibition in inhibitory NA terminals innervating the B 1 group. These results also illustrate the heterogeneities in the responses of the 5-HT nerve cell groups to antidepressant treatment. The ability of chronic imipramine treatment to increase SP IR in the dorsal horn of the lumbar enlargement may reflect the existence of a monoamine-SP interaction in the substantia gelatinosa due to the NA and/or 5-HT uptake blocking activity of imipramine. The existence of such an interaction may help to explain the antinociceptive effect of chronic imipramine treatment.Part of the paper was presented at the 17th International Congress of the International Society of Psychoneuroendocrinology, Bergen, June 29–July 4, 1986.  相似文献   
76.
Human fetal spinal cord poly A (+) mRNA was found to direct the synthesis of three major myelin basic protein (MBP) variants with molecular weights of 17K, 18.5K, and 21.5K when translated in reticulocyte lysates. In order to investigate the structural relationships between these MBP variants and their corresponding mouse variants, human fetal spinal cord and mouse brain cDNA libraries were constructed and screened for MBP cDNAs. A number of MBP cDNA clones were isolated and characterized. One of these, PP535 contained the entire coding region of the mouse 14K MBP; and another mouse cDNA clone, PP1.85, was almost full-length and coded for either the 21.5K MBP or the 18.5K MBP. A human clone (KK36), 1,173 nucleotides in length, contained the entire coding region of an MBP variant with a molecular weight of 17,342. The structure of this clone within its coding region is significantly different from the corresponding mouse 17K MBP cDNA. It is missing two sequences found in the mouse 17K MBP cDNA (exons 2 and 5); and it contains a sequence (exon 6) that is missing from the mouse 17K MBP cDNA. Thus, this human 17.3K cDNA codes for a "17K" human MBP variant that is quite different from the corresponding mouse variant and is identical to the human 18.5K MBP except for a deletion of a peptide consisting of 11 amino acids that includes the single tryptophan residue of the 18.5K MBP. An analysis of the structure of this 17.3K human MBP cDNA suggests that the major pathway for splicing the primary human MBP gene product may be different from that in the mouse.  相似文献   
77.
目的为探讨咽旁间隙肿瘤的诊断与治疗.方法报告28例咽旁间隙肿瘤的临床资料.结果良性肿瘤24例,其中神经源性肿瘤10例,涎腺混合瘤9例,其它5例;恶性肿瘤4例.全部病例均行手术治疗.结论颈侧切开为一较好的手术径路.  相似文献   
78.
正多数下肢动脉栓塞病人在急性期内(发病6~8 h以内)行手术治疗可取得较好的治疗效果,但部分病人可能因医疗条件或个人原因而选择保守治疗(如仅使用抗凝药物等),下肢动脉部分开放或仅侧支开放,将疾病由急性期拖入了亚急性期,此时的血栓机化,并且与血管内膜粘连紧密不易分开。笔者团队自制可调节式内膜剥离器用于取出亚急性下肢动脉栓塞病人的陈旧性机化血栓。现报告如下。  相似文献   
79.
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   
80.
Summary The effects of morphine-HCl (MOR), methionine-enkephalin (ME) and dynorphin1–13 (DYN) on spinal and spino-bulbo-spinal (SBS) reflexes were studied. Although spinal intrathecal administration of MOR (15g) did not produce any apparent effect on these reflexes, systemically administered MOR (3mg/kg i.v.) reduced the electrical toe stimulation-induced SBS reflex. Furthermore, MOR (3mg/kg i.v.) increased the polysynaptic reflex induced by electrical stimulation of low-threshold dorsal root afferents in intact (non-spinal) rats, but not in spinal rats. Intrathecally administred DYN (0.5 and 5 g) reduced both the electrical toe stimulation-induced spinal and SBS reflexes, while ME (15g) only reduced the SBS reflex. These results indicate the physiological multiplicity of spinal opioid receptors. MOR may affect supraspinal nuclei but not the spinal pathway which possesses MOR-sensitive opioid receptors, whereas ME and DYN affect spinal opioid peptide receptors and modulate the reflex activities in which they participate.  相似文献   
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