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21.
The position of the motornuclei projecting through the median (Mn) and ulnar (Ul) nerves to the cat distal forelimb has been investigated. Horseradish peroxidase (HRP) and fluorescent (Fl) compounds have been used as retrograde tracers. They were either injected into forelimb muscles or applied to the proximal end of transected forelimb nerves. Limb muscles that were not investigated were carefully denervated. The position and the architecture of the individual motornuclei were traced with HRP. The topographical relations between the nuclei were established with application of up to three different Fl compounds in the same animal. The Mn motoneurones had a bimodal distribution in the brachial spinal cord. The motoneurones to the pronator teres and flexor carpi radialis muscles were located in C7 and the other Mn motoneurones were located in C8 and Th1. In C7 the Mn motoneurones occupied a single representation area, which is located some distance medially of the lateral funiculus. In C8 and Th1 two Mn representation areas were found: A dorsal one that contacts the lateral funiculus and is located at the level of the central canal; a ventral one that is located ventrally in the ventral horn. The dorsal area is occupied by the motornuclei projecting to the intrinsic hand muscles and the ventral one by the nuclei projecting to the limb. The Ul motoneurones extend with an unimodal distribution from the caudal C7 to the caudal Th1 segments. They occupy a single, broad representation area. The dorsal part, which contacts the lateral funiculus, is located at the level of the central canal and harbours the nuclei to the intrinsic hand muscles. The other Ul nuclei are located ventromedially deep in the ventral horn. These results, together with those from the companion paper on the location of the deep radial motornuclei, provide important anatomical information for the investigation of the cat brachial enlargement. 相似文献
22.
硒对二乙基亚硝胺诱发大鼠肝癌生长的抑制作用的观察 总被引:3,自引:0,他引:3
观察硒对二乙基亚硝胺诱发大鼠肝癌的影响。方法;在诱癌过程中,大鼠分别投予含0.2,1.0,3.0×10^-6硒的饲料,检测血,肝组织LPO,GSH-PX活性,观察诱癌率及癌结节面积。结果:补Se后对诱癌率无显著影响,但补充3.0×1-0^-6Se可使癌结节面积显著减少。补Se可显著地减轻诱癌早期血和肝组织中LPO的形成及诱癌过程中血和肝组织中GSH-PX活性的降低。 相似文献
23.
雄性大白鼠球海绵体肌和坐骨海绵体肌的运动神经元—HRP法研究 总被引:1,自引:0,他引:1
本实验用HRP注射于大白鼠的一侧球海绵体肌和坐骨海绵体肌后,在脊髓腰骶段的不同平面可观察到支配该两肌的运动神经元胞体出现标记并具有一定的局部定位关系。支配球海绵体肌的运动神经元主要位于L_5~S_1的背内侧群,而支配坐骨海绵体肌的运动神经元主要位于背外侧群和腹侧群。本文认为大白鼠腰骶段前角背内侧群和背外侧群同腹外侧群细胞一样,同属于Onuf's核的同源神经细胞。本文还观察了大白鼠腰骶段脊髓前柱细胞的配布。 相似文献
24.
T. Sakumoto M. Tohyama K. Satoh Y. Kimoto T. Kinugasa O. Tanizawa K. Kurachi N. Shimizu 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1978,31(1):81-94
Summary Attempts were made to determine the afferent projections to the anterior hypothalamus including the preoptic area from the lower brain stem by means of the horseradish peroxidase method combined with monoamine oxidase staining to identify noradrenaline (NA) neurons. In addition to this technique, a histofluorescence analysis was performed. NA fibers in the medial part of the anterior hypothalamus were mainly supplied by A1 and A2 NA neuron groups, while the lateral part and periventricular zone received NA terminals from both pontine and medulla oblongata NA neuron groups. Furthermore, the present study indicated that there were direct projections to the anterior hypothalamus from non-noradrenergic neurons in the lower brain stem: nuclei raphe dorsalis, centralis superior, cells in the mesencephalic and pontine central gray matter, nuclei parabrachialis lateralis and medialis, cells around fasciculus longitudinalis medialis.Abbreviations CA
Commissura anterior
- CO
Chiasma opticum
- DP
Decussatio pyramidum
- DPCS
Decussatio pedunculorum cerebellarium superiorum
- F
Columna fornicis
- FLM
Fasciculus longitudinalis medialis
- FMT
Fasciculus mamillothalamicus
- GCM
Griseum centrale mesencephali
- GCP
Griseum centrale pontis
- LL
Lemniscus lateralis
- LM
Lemniscus medialis
- PCM
Pedunculus cerebellaris medius
- PCS
Pedunculus cerebellaris superior
- TO
Tractus opticus
- TS
Tractus solitarius
- TVme
Tractus mesencephalicus nervi trigemini
- V
Ventriculus tertius
- VTS
Tractus spinalis nervi trigemini
- am
nucleus ambiguus
- B
Barrington nucleus
- com
nucleus commissuralis
- cp
nucleus caudatus putamen
- cs
nucleus centralis superior
- ct
nucleus corporis trapezoidei
- cu
nucleus cuneatus
- dX
nucleus dorsalis nervi vagi
- Gd
nucleus tegmentalis dorsalis (von Gudden)
- gr
nucleus gracilis
- Gv
nucleus tegmentalis ventralis (von Gudden)
- ha
nucleus hypothalamicus anterior
- hl
nucleus hypothalamicus lateralis
- hpe
nucleus periventricularis (hypothalami)
- hvm
nucleus ventromedialis hypothalami
- lc
nucleus locus coeruleus
- oi
nucleus olivaris inferior
- p
nucleus pontis
- pa
nucleus paraventricularis
- pbl
nucleus parabrachialis lateralis
- pbm
nucleus parabrachialis medialis
- ph
nucleus praepositus hypoglossi
- pol
nucleus preopticus lateralis
- pom
nucleus preopticus medialis
- pop
nucleus preopticus periventricularis
- rd
nucleus raphe dorsalis
- re
nucleus reuniens
- rl
nucleus reticularis lateralis
- rm
nucleus raphe magnus
- ro
nucleus raphe obscrus
- sc
nucleus suprachiasmaticus
- so
nucleus supraopticus
- st
nucleus interstitialis striae terminalis
- td
nucleus tractus diagonalis (Broca)
- ts
nucleus tractus solitarii
- Vme
nucleus mesencephalicus nervi trigemini
- Vmo
nucleus motorius nervi trigemini
- Vts
nucleus tractus spinalis nervi trigemini
- XII
nucleus nervi hypoglossi 相似文献
25.
Bahram Dalir-Naghadeh Siamak Asri-Rezaei Naser Alidady 《Comparative clinical pathology》2006,15(3):149-153
Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis. 相似文献
26.
Central cholinergic pathways in the rat: An overview based on an alternative nomenclature (Ch1–Ch6) 总被引:12,自引:0,他引:12
Monoclonal antibodies to choline acetyltransferase and a histochemical method for the concurrent demonstration of acetylcholinesterase and horseradish peroxidase were used to investigate the organization of ascending cholinergic pathways in the central nervous system of the rat. The cortical mantle, the amygdaloid complex, the hippocampal formation, the olfactory bulb and the thalamic nuclei receive their cholinergic innervation principally, from cholinergic projection neurons of the basal forebrain and upper brainstem. On the basis of connectivity patterns, we subdivided these cholinergic neurons into six major sectors. The Chl and Ch2 sectors are contained within the medial septal nucleus and the vertical limb nucleus of the diagonal band, respectively. They provide the major cholinergic projections of the hippocampus. The Ch3 sector is contained mostly within the lateral portion of the horizontal limb nucleus of the diagonal band and provides the major cholinergic innervation to the olfactory bulb. The Ch4 sector includes cholinergic neurons in the nucleus basalis, and also within parts of the diagonal band nuclei. Neurons of the Ch4 sector provide the major cholinergic innervation of the cortical mantle and the amygdala. The Ch5–Ch6 sectors are contained mostly within the pedunculopontine nucleus of the pontomesencephalic reticular formation (Ch5) and within the laterodorsal tegmental gray of the periventricular area (Ch6). These sectors provide the major cholinergic innervation of the thalamus. The Ch5–Ch6 neurons also provide a minor component of the corticopetal cholinergic innervation.
These central cholinergic pathways have been implicated in a variety of behaviors and especially in memory function. It appears that the age-related changes of memory function as well as some of the behavioral disturbances seen in the dementia of Alzheimer's Disease may be related to pathological alterations along central cholinergic pathways. 相似文献
27.
28.
研究了纳米硒和亚硒酸钠对断奶仔猪肝脏谷胱甘肽过氧化物酶和脱碘酶活性的影响。将纳米硒和亚硒酸钠2种硒源分别以0.1、0.2、0.3、0.4、0.5、1.0 mg/kg 6个硒水平添加到基础日粮中,配制成12种试验日粮,基础日粮作对照,饲养“杜长大”断奶仔猪(8.3 kg左右)。结果表明:以亚硒酸钠形式添加的硒浓度为1.0 mg/kg时,仔猪生长性能和GSH-Px活性显著低于0.2~0.4 mg/kg硒添加水平(P<0.05),纳米硒添加浓度为1.0 mg/kg,仔猪生长性能和GSH-Px活性仍然保持在高峰平台;硒源添加浓度为0.10~0.40 mg/kg时,两种硒源对GSH-Px活性的影响无显著差异(P>0.05);在0.50和1.0 mg/kg硒添加水平上,纳米硒组GSH-Px活性显著高于亚硒酸钠组(P<0.05)。基础日粮组肝脏脱碘酶活性显著低于各硒源的添加水平(P<0.05),硒源和硒添加水平对脱碘酶活性没有显著影响(P>0.05)。上述结果提示:纳米硒的Weinberg剂量-效应的最适剂量范围宽于亚硒酸钠。 相似文献
29.
Anti-human thyroid peroxidase and anti-human thyroglobulin antibodies present no cross-reactivity on recombinant peptides.
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Thyroglobulin (Tg) and thyroid peroxidase (TPO) are two antigens largely recognized by the sera from patients with autoimmune thyroid disease (AITD). Recently, the complete mapping of both antigens was established with rabbit polyclonal antibodies by the use of recombinant proteins expressed in prokaryotic vector. Several investigators have argued for the existence of a cross-reactivity of some hetero- and autologous antibodies versus these two proteins. In the present study, using rabbit polyclonal antibody, mouse polyclonal antibody and autoimmune antibody (aAb), we observed no common epitope on human Tg (hTg) and human TPO (hTPO). 相似文献
30.
A J Beitz 《Neuroscience》1982,7(11):2753-2768
The sites of origin of brain stem enkephalin and substance P projections to the rodent nucleus raphe magnus were studied utilizing the combined horseradish peroxidase retrograde transport-peroxidase-antiperoxidase immunohistochemical technique. Several brain stem areas were found to contain both enkephalin- and substance P-like immunoreactive double labeled neurons following injection of horseradish peroxidase into the raphe magnus. Nuclei providing both enkephalin and substance P inputs to the raphe magnus include the nucleus reticularis paragigantocellularis, the nucleus cuneiformis, the nucleus solitarius and the trigeminal subdivision of the lateral reticular nucleus. Enkephalin projections to the raphe magnus were also found to originate from the dorsal parabrachial nucleus, the nucleus reticularis gigantocellularis pars α and from an area which corresponds to the A5 group of Dahlström &; Fuxe. Additional neurons containing substance P-like immunoreactivity and horseradish peroxidase reaction product were identified in the superior central raphe nucleus and the nucleus pontis oralis. The midbrain periaqueductal gray contributes very few enkephalin and substance P fibers to the raphe magnus.The nucleus raphe magnus is a key structure in the intrinsic analgesia system and it has also been implicated in other diverse and non-nonciceptive functions. The present study identifies several brain stem sites which provide enkephalin and substance P input to this raphe nucleus. Several of these nuclei have been implicated in central analgesic mechanisms or in non-nociceptive autonomic functions. The present investigation raises the possibility that these brain stem regions may modulate neuronal activity in the raphe magnus via enkephalin or substance P projections and thus influence the involvement of the raphe magnus in both opiate related mechanisms of pain control and non-nociceptive functions. 相似文献