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61.
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63.
K. D. Kniffki S. Mense R. F. Schmidt 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1978,31(4):511-522
Summary In an attempt to differentiate between nociceptive group IV muscle receptors and ergoceptive ones, the discharges of single group IV fibres from skeletal muscle in response to local pressure, sustained stretch, repetitive contraction and intra-arterial injections of bradykinin, 5-hydroxytryptamine (5-HT), potassium, phosphate, and lactate were studied in anaesthetized cats.Of the 75 fibres of the study, 5 units were activated by sustained stretch, the responses occurring with a delay. These stretch-sensitive units could not be activated by local pressure or muscular contraction. Thirteen group IV afferents raised their discharge frequency during repetitive contractions. Some of the units responded immediately with the onset of the contractions, whereas the others showed a pronounced delay.Forty-six units were tested with all or most of the above mechanical and chemical stimuli. In 32 afferents a response to at least one of the stimuli was present. Taking only these units into account, several groups of receptors could be distinguished by their different response combinations. One group was activated by pain-producing substances, but not by muscular activity and thus showed nociceptive properties. Another group showed a raised activity during muscular contractions but did not respond to the algesic agents bradykinin and 5-HT. Units belonging to this group might serve as ergoceptors. The borderline between the two groups was not sharp, a considerable number of group IV afferents was found which had both nociceptive and ergoceptive properties. 相似文献
64.
Dr. S. M. Highstein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1973,17(3):285-300
Summary Intracellular and extracellular responses were recorded with glass micro-electrodes from motoneurons in the IIIrd and IVth cranial nuclei of anesthesized rabbits. Five subgroups of neurons innervating the superior rectus (SR), inferior oblique (IO), inferior rectus (IR), medial rectus (MR), and superior oblique (IVth) extraocular muscles were identified by their antidromic activation from the branches of the IIIrd and IVth cranial nerves. The relative positions of the subgroups thus determined were consistent with the histological data on the rabbit. In the SR, IO, IR, and IVth subgroups the effects of ipsilateral VIIIth nerve stimulation were inhibitory, producing disynaptic IPSPs, while the effects of contralateral VIIIth nerve stimulation were excitatory, producing disynaptic EPSPs. In the MR subgroup, however, a mixture of EPSPs and IPSPs was produced by VIIIth nerve stimulation: this was particularly clear on the ipsilateral side. Sites relaying these VIIIth nerve effects to each of the five subgroups were explored by direct stimulation of various brain stem sites. Stimulation of the superior vestibular nucleus (SV) produced IPSPs monosynaptically in all five subgroups on the ipsilateral side as well as in the contralateral MR subgroup. Stimulation of the medial vestibular nucleus (MV) produced EPSPs monosynaptically in all of the five subgroups on the contralateral side as well as in the ipsilateral MR subgroup. Stimulation of the brachium conjunctivum (BC) also produced EPSPs monosynaptically in the contralateral SR, IO, and IR subgroups. Further, while the recording electrode was placed within each of the five subgroups to observe the extracellular potentials corresponding to the intracellularly recorded IPSPs and EPSPs, the medulla and cerebellum were systematically tracked with a monopolar stimulating electrode. It was thus confirmed that the SV is the sole inhibitory relay site, while excitation is relayed by both the MV and the BC. The origin of the BC pathway was traced to the Y-Group for the IO, to the lateral nucleus of the cerebellum (LN) for the IR, and to both the Y-Group and the LN for the SR subgroup. 相似文献
65.
Polymorphism of human leukocyte antigen-DRB1, -DQB1, and -DPB1 genes of Shandong Han population in China 总被引:6,自引:0,他引:6
In the present study, polymerase chain reaction-sequence-based typing (PCR-SBT) was used to analyze human leukocyte antigen (HLA)-DRB1, -DQB1, and -DPB1 alleles of 98 unrelated healthy Shandong Han individuals. A total of 60 alleles, in which 28 in DRB1, 15 in DQB1 and 17 in DPB1 were found. Among the 28 detected DRB1 alleles, DRB1*150101, DRB1*070101, DRB1*090102, DRB1*120201, and DRB1*080302 were commonly observed, with frequencies of 16.3%, 11.2%, 10.2%, 8.2%, and 5.6%, respectively. The most predominant DQB1 allele was DQB1*030101/0309 with the frequency of 20.4%, followed by DQB1*0201/0202 (14.8%), DQB1*0602 (14.3%), DQB1*030302 (12.2%), and DQB1*060101/060103 (10.7%). Of the 17 detected DPB1 alleles, DPB1*0501 was the most frequent allele with the frequency of 37.2%. DPB1*020102 (18.4%), DPB1*040101 (11.2%), DPB1*0402 (7.1%), and DPB1*1701 (6.6%) were also very frequent alleles. A total of 53 estimated DRB1-DQB1 two-locus haplotypes were observed in Shandong Han population, of which DRB1*150101-DQB1*0602 was the most predominant, followed by DRB1*090102-DQB1*030302, DRB1*070101-DQB1*0201/0202 DRB1*120201-DQB1*030101/0309, and DRB1*080302- DQB1*060101/060103. The distribution of the HLA class II alleles and haplotypes frequencies as well as the dendrogram showed that the Shandong Han population belongs to the northern group of Chinese. The data have implications for anthropological studies and disease associations. 相似文献
66.
蒙古族、回族和汉族的发旋调查 总被引:2,自引:0,他引:2
对蒙古族、回族和汉族共6098例发旋进行了观察,结果:蒙古族单旋出现率高于回族和汉族,而双旋则低于这两个民族,差异极其显著(P<0.01)。三个民族男性双旋均高于本民族女性(P<0.01)。双旋的组合除文献报道的四种类型外,还有四种组合方式。 相似文献
67.
79例广东汉族人群HLA-Cw及其KIR分析 总被引:2,自引:0,他引:2
目的:了解HLA—Cw与相应刺激性KIR(杀伤细胞免疫球蛋白样受体)和抑制性KIR在广东汉族人群中的分布。方法:对79例广东汉族骨髓移植供者,以DNA技术检测HLA-Cw和KIR表型。根据对KIR识别的特异性,将HLA-Cw分为HLA-Cw^lys.HLA-Cw^asn,分析个体HLA-Cw与相应刺激性或抑制性KIR的识别情况。结果:本组人群中,HLA-Cw^lys、HLA-Cw^asn的频率分别为26.6%、97.5%。表达KIR2DL1而无栩应配体者62.0%,表达2DS1而无相应配体者15.1%。27.8%表达HLA-Cw^asn而不表达相应KIR。25.3%、55.6%有抑制性HLA-Cw^lys或HLA-Cw^asn配体受体对,1.3%和14.0%的个体单独表达刺激性HLA-Cw^lys扣或HLA-Cw^asn配体受体对。15.1%的个体表达KIR2DS1而不表达HLA-Cw^lys。结论:在广东汉族人群中,存在KIR表型与自身HIA表型分离现象。抑制性HIA-Cw-KIR配对表达高于刺激性配对,约1/5单独表达刺激性HLA-Cw—KIR配对。 相似文献
68.
维吾尔族、汉族初中毕业生考前心理状态的调查与分析 总被引:5,自引:1,他引:5
青少年期是人生的黄金段 ,是个体从儿童过渡到成年 ,逐步走向成熟的中间阶段。这一阶段的生理及心理变化大 ,容易产生心理问题。特别是在初中毕业前 ,还面临今后的前途问题 ,心理状态更加复杂。本文对本地区人口最多的维吾尔族和汉族初中毕业生考前心理状态进行了调查与分析 ,以了解不同文化背景、不同民族的初中毕业生考前心理状态 ,为青少年心理健康咨询提供指导。1 调查对象与方法1.1 调查对象新疆乌鲁木齐市第五中学 (维吾尔族中学 )。1999年初中毕业生共 170名 ,全部为维吾尔族 ,其中 :男 75名 ,女生 95名 ,年龄 14~ 16岁。新疆乌鲁… 相似文献
69.
Aimonetti JM Vedel JP Schmied A Pagni S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,133(3):391-401
The question of whether Ia reciprocal inhibition might depend on the motor task and on the type of motor unit activated was investigated in the human extensor carpi radialis muscles. Ia reciprocal inhibition induced by stimulating the median nerve (conditioning stimulation) was estimated by measuring the changes in the firing probability of 37 extensor motor units in response to the radial nerve stimulation (100 test stimuli) delivered 1 ms after the conditioning stimulation. Six subjects were asked to perform a task consisting of either selectively contracting their wrist extensor muscles or co-activating their wrist and finger antagonist muscles by clenching their hand around a manipulandum. In the control recordings (test stimulation alone), the mean response probability of the 37 motor units was found to be greater during hand clenching. The motor units were identified on the basis of their force thresholds, their macro-potentials, and their twitch contraction times. The data obtained in the control recordings were consistent with the size principle. In the recordings where the responses were conditioned by applying median nerve stimulation, the response probability of the motor units with low force thresholds, small macro-potential areas, and long twitch contraction times tended to decrease, in line with the presence of Ia reciprocal inhibition, whereas the response probability of the motor units with higher force thresholds, larger macro-potential areas, and shorter twitch contraction times tended to increase. The median nerve stimulation may therefore have altered the efficiency with which the extensor Ia inputs recruited the homonymous motoneurones in the pool. The flexor group I afferents activated while the median nerve was stimulated had inhibitory effects on the slow contracting motor units, and facilitatory effects mainly on the fast contracting motor units. Both of these effects were stronger during hand clenching, in which the numerous cutaneous receptors of the palm and fingertips are liable to be activated. Besides their own effects on the excitability of the various types of motor units, cutaneous inputs are known to potentiate the Ib interneurones. In addition, the effects of the conditioning stimulation were superimposed on the tonic activity of the Ia and Ib afferents from the flexor wrist and finger muscles. This may explain why both the inhibitory and facilitatory effects of the median nerve stimulation were enhanced during hand clenching. 相似文献
70.
The terminal nucleotide sequences of group C Cowden rotavirus gene segments 1-4 were determined. When compared with the published sequences, we found 14 to 29 additional nt at the 5 ends of the four reported gene sequences. For the 3 ends, we observed an additional 16 nt in gene 2 and 14 fewer nt in gene 4. 相似文献