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1.
目的观察神经干细胞经脑室注射后在损伤脊髓的早期动态变化。方法取转录有绿色荧光蛋白(GFP)基因的孕16天SD鼠胚脑海马组织,培养成神经干细胞球,注射到损伤脊髓鼠第四脑室(实验组),观察其在脊髓的存活、分化状况。结果移植细胞在脊髓表面形成细胞团。分布于损伤区头侧。细胞团的面积背侧小于腹侧;数目背侧多于腹侧。这种分布和增殖形式见于损伤脊髓正常部分和无损伤脊髓(对照组)。1周时细胞侵入损伤区,GFAP表达呈阳性。2~3周时与宿主细胞良好整合。结论移植细胞通过脑脊液能广泛分布于脊髓表面。保持黏附、增殖和分化能力。并可迁移、整合到损伤脊髓组织中。  相似文献   
2.
这种形态的文学其最为显著的标志是内倾化即自剖,暴露作家的思想观念,心灵情绪直到作家的私生活,包括作家的性心理与性行为等在一般社会眼中视为卑微的东西。作家们弘扬个人的心灵欲望,宣泄“食与色”的双重焦虑与痛苦,其思想内涵无疑带有强烈的反封建色彩。其批判的向度指向内外两个方面,既有对自我心灵严酷的审视,又有对于社会与国家的无情拷问。  相似文献   
3.
Cannabinoids have been shown to influence food intake, and until recently, the neural pathways mediating these effects have remained obscure. It has been previously shown that intracerebroventricular injection of delta-9-tetrahydrocannabinol (Δ9-THC) causes increased consumption of palatable foods in rats, and we postulated the involvement of the hindbrain in this cannabinoid-induced food intake. Cannulated rats (both female and male groups) trained to consume sweetened condensed milk received either lateral or fourth ventricle injections of CP 55,940 and were presented with sweetened condensed milk 15 min after injection. Rats were injected over a range of doses between 100 pg and 10 μg per rat. Milk intake was recorded for a total of 3 h. Lateral ventricle injection of CP 55,940 increased milk intake at doses in the microgram range. However, CP 55,940 was effective in increasing food intake at nanogram doses when injected into the fourth ventricle. Finally, male rats appeared to be more sensitive to CP 55,940 than female rats inasmuch as milk consumption was increased at the 1 ng dose in male rats, whereas only the 10 ng dose was effective in females. These results indicate that CP 55,940 may act in the hindbrain to influence feeding behavior in rats.  相似文献   
4.
Twenty-four adult cadavers (48 sides) were used to investigate the incidence of a branch arising from the ventral ramus of the fourth cervical nerve (C4) with the phrenic nerve and subsequently joining the brachial plexus. Six brachial plexuses with spinal cords and phrenic nerves were dissected under a surgical microscope to investigate localization of fibers contained in the C4 branch to the brachial plexus. The incidence of the C4 branch was 23% (11/48 sides). Branches from C4 to the brachial plexus divided into anterior and posterior divisions on four sides (4/6 sides). On two sides, the branch did not divide but consisted entirely of an anterior division (2/6 sides). In the brachial plexus, anterior division fibers of the C4 branch were intertwined with fibers from the anterior divisions of the ventral rami of the fifth and sixth cervical nerves. They then passed to the suprascapular nerve and the anterior division of the superior trunk (6/6 sides). On the other hand, posterior division fibers of the C4 branch were intertwined with fibers from the posterior divisions of the ventral rami of the fifth and sixth cervical nerves. They then passed to the suprascapular nerve (2/6 sides) and the posterior division of the superior trunk (4/6 sides). The anterior division of the C4 branch received fibers from the ventral rootlets of the entire fourth cervical segment, whereas the posterior division received fibers from the ventral rootlets of the caudal half of the fourth cervical segment only. The fact that the suprascapular nerve received fibers from both the anterior and posterior divisions of the C4 branch was considered to support our claim that the human suprascapular nerve belongs to both the anterior and posterior divisions of the brachial plexus.  相似文献   
5.
持续性正加速度致意识丧失的机理及其监测   总被引:5,自引:0,他引:5  
正在加速度引起的意识丧失(G-LOC)是当胶威胁飞行安全的主要因素。综述了G_LOC的机理及其生理监测,慢增长率正加速度导致的意识丧失的机理主要大脑缺血/缺氧;快增长率正加速度导致物意识丧失可能与颅内高应力有关,但缺直接的实验证据。用于G-LOC监测的生理指标中,眼水平动脉血压、脑氧饱和度等可能具有重要作用。  相似文献   
6.
Benzodiazepines have been reported to induce eating when administered into the brainstem of rats (either the fourth ventricle or the parabrachial nucleus). Benzodiazepines in the brainstem also have been reported to enhance the hedonic impact of taste, as measured by hedonic/aversive taste reactivity patterns, when administered to the fourth ventricle. The present study examined whether the parabrachial nucleus in particular is a brainstem site of the benzodiazepine-produced enhancement of eating and palatability. Food intake (cereal mash) was measured after brainstem microinjections of midazolam or vehicle (0.0, 7.5, and 15.0 microg) into the parabrachial nucleus, the nucleus of the solitary tract, the pedunculopontine tegmental nucleus, or the fourth ventricle (60 microg). We used the taste reactivity paradigm to measure hedonic/aversive affective reactions elicited from rats by oral infusions of a bittersweet solution (7% sucrose-0.01% quinine). Positive hedonic reactions and negative aversive reactions to sucrose-quinine were also measured after microinjections of midazolam (0.0, 7.5, and 15 microg) into the parabrachial nucleus. Midazolam increased food intake and selectively enhanced positive hedonic taste reactivity patterns to the bittersweet solution when microinjections were delivered to the parabrachial nucleus. When administered to the other brainstem sites at the same doses, however, midazolam had no effect. We therefore conclude that the parabrachial nucleus can mediate the benzodiazepine-induced enhancement of the hedonic impact of taste as well as mediating the enhancement of eating behavior.  相似文献   
7.
The pace of publication in consumer health continues unabated. EBSCO’s Health Source – Consumer Edition provides one of the few indexing and abstracting services to assist users looking to these types of publications for help with their health questions. This column provides a guide to some of the database features and resources. While the reading level for some of its indexed sources is relatively high, and the collection of books is dated at present. Health Source – Consumer Edition remains a valuable tool in the consumer health librarian’s toolkit.  相似文献   
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