全文获取类型
收费全文 | 259篇 |
免费 | 0篇 |
国内免费 | 2篇 |
专业分类
儿科学 | 2篇 |
基础医学 | 64篇 |
临床医学 | 11篇 |
内科学 | 3篇 |
神经病学 | 131篇 |
特种医学 | 2篇 |
外科学 | 3篇 |
综合类 | 33篇 |
药学 | 10篇 |
中国医学 | 2篇 |
出版年
2023年 | 1篇 |
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 4篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 7篇 |
2010年 | 5篇 |
2009年 | 3篇 |
2008年 | 10篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 1篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 10篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 9篇 |
1996年 | 3篇 |
1995年 | 7篇 |
1994年 | 5篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 11篇 |
1986年 | 11篇 |
1985年 | 15篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 10篇 |
1981年 | 14篇 |
1980年 | 8篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有261条查询结果,搜索用时 8 毫秒
21.
Microinjection of neurotensin into the rat rostroventromedial medulla produces dose-dependent inhibition of the tailflick reflex (ED50 of 2.06 nmol/animal (1.33–3.19)). The peak effect occurs 15–20 min following injection and, at the highest dose used, lasts up to 70 min. 相似文献
22.
Electrical stimulation of the nucleus raphe magnus (NRM) inhibits some somatic and visceral input at the spinal level. This study was designed to examine the effects of electrical and chemical stimulation of NRM on neuronal responses to afferent renal nerve (ARN) stimulation. In chloralose-anesthetized rats, electrical stimulation of ARN elicited predominantly excitatory responses in spinal gray neurons. In 10 neurons studied, electrical stimulation of the NRM elicited an inhibition of spontaneous activity of 8 neurons and inhibited evoked responses to ARN stimulation in 6 neurons. Microinjection of glutamate (5-10 nmol in 0.5-1 microliter) into the NRM elicited an inhibition of spontaneous activity in 9 neurons, a facilitation in 6 neurons and no response in 8 neurons receiving ARN input. Responses evoked by ARN stimulation were inhibited in 12 neurons, facilitated in 4 neurons and not affected in 8 neurons. We conclude that renal input can be modulated at the spinal level by activation of the NRM and adjacent tissue. Furthermore, the inhibition of spinal gray neuronal responses elicited by stimulation of the NRM appears to be due, at least in part, to activation of fibers of passage since non-selective electrical stimulation is more efficacious than selective chemical stimulation of neuronal soma and dendrites. 相似文献
23.
24.
The rostral ventromedial medulla (RVM) is involved in facilitation of spinal nociceptive processing and generation of hyperalgesia in inflammatory and neuropathic pain models. We hypothesized that the bilateral hyperalgesia that develops after repeated intramuscular injections of acidic saline is initiated and maintained by activation of descending facilitatory pathways from the RVM. Male Sprague-Dawley rats were implanted with intracerebral guide cannulae into the nucleus raphe magnus (NRM) or the nucleus gigantocellularis (Gi). Two injections of acidic saline into one gastrocnemius muscle 5 days apart lead to robust hyperalgesia after the second injection. Either ropivacaine (local anesthetic) or vehicle (control) was microinjected into the RVM prior to the first intramuscular acid injection, prior to the second injection, or 24h after the second injection. Mechanical withdrawal thresholds of the paw (von Frey filaments) and the muscle (tweezer) were measured before and 24h after induction of hyperalgesia. The withdrawal thresholds for both the paw (cutaneous secondary hyperalgesia) and muscle (primary hyperalgesia) were decreased 24h after the second intramuscular acid injection in the vehicle control groups. Administration of ropivacaine prior to the first intramuscular acid injection had no effect on development of either cutaneous or muscle hyperalgesia that develops after the second injection. However, neither cutaneous nor muscle hyperalgesia developed in the group treated with ropivacaine prior to the second intramuscular injection. Ropivacaine also significantly reversed the hyperalgesia in the group treated 24h after the second intramuscular acid injection. Thus, the RVM is critical for both the development and maintenance of hyperalgesia after muscle insult. 相似文献
25.
Cortico-NRM influences on trigeminal neuronal sensation 总被引:1,自引:0,他引:1
Lambert GA Hoskin KL Zagami AS 《Cephalalgia : an international journal of headache》2008,28(6):640-652
We tested the idea that migraine triggers cause cortical activation, which disinhibits craniovascular sensation through the nucleus raphe magnus (NRM) and thus produces the headache of migraine. Stimulation of the dura mater and facial skin activated neurons in the NRM and the trigeminal nucleus. Stimulation of the NRM caused suppression of responses of trigeminal neurons to electrical and mechanical stimulation of the dura mater, but not of the skin. This suppression was antagonized by the iontophoretic application of the 5-HT1B/1D receptor antagonist GR127935 to trigeminal neurons. Migraine trigger factors were simulated by cortical spreading depression (CSD) and light flash. Activity of neurons in the NRM was inhibited by these stimuli. Multiple waves of CSD antagonized the inhibitory effect of NRM stimulation on responses of trigeminal neurons to dural mechanical stimulation but not to skin mechanical stimulation. The cortico-NRM-trigeminal neuraxis might provide a target for a more universally effective migraine prophylactic treatment. 相似文献
26.
Termination patterns of serotoninergic medullary raphespinal fibers in the rat lumbar spinal cord: an anterograde immunohistochemical study 总被引:2,自引:0,他引:2
Electrical and chemical stimulation given in the ventral medullary raphe nuclei inhibits spinal nociceptive reflexes and spinal nociceptive transmission; serotoninergic receptors have been demonstrated to partially mediate that inhibition. In the present study, the termination patterns of raphespinal fibers in the rat lumbar spinal cord demonstrating serotonin-like immunoreactivity were examined by using the anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA-L) in combination with immunohistochemistry. Fibers and terminations from the ventral medullary raphe nuclei (raphe magnus and raphe pallidus) demonstrating both PHA-L- and serotonin-like immunoreactivity were identified in all laminae of the dorsal horn and the ventral horn. Networks of large fibers, characterized by large boutons, and which did not demonstrate serotonin-like immunoreactivity, were identified in deeper laminae of the dorsal horn. The heterogeneous morphology of raphespinal fibers identified in the dorsal horn suggests that these fibers also may be heterogeneous in neurochemistry and function. Medial medullary sites outside the raphe nuclei were found to innervate the ventral horn and all laminae of the dorsal horn, with the exception of lamina I. Descending fibers and terminations also demonstrating serotonin-like immunoreactivity were identified in deep laminae (III, IV, V, VI) of the dorsal horn and in the ventral horn. Similarly, large fiber networks were identified which did not demonstrate serotonin-like immunoreactivity. 相似文献
27.
The aim of the current study was to investigate the role of the rostroventromedial medulla (RVM) in α2-adrenoceptor-mediated antinociception. Medetomidine or clonidine, selective α2-adrenoceptor agonists were microinjected into the RVM in unanesthetized rats with a chronic guide cannula. The antinociceptive effects were evaluated using the tail-flick and hot-plate tests. For comparison, medetomidine was microinjected into the cerebellum or the periaqueductal gray (PAG). To study the role of medullospinal pathways, the tail-flick latencies were also measured in spinalized rats. The reversal of the antinociception induced by intracerebral microinjections of medetomidine was attempted by s.c. atipamezole, a selective α2-adrenoceptor antagonist. The reversal of the antinociception induced by systemic administration of medetomidine was attempted by microinjections of 5% lidocaine or atipamezole into the RVM. When administered into the RVM, medetomidine produced a dose-dependent (1–30 μg) antinociception in the tail-flick and hot-plate tests, which antinociceptive effect was completely reversed by atipamezole (1 mg/kg, s.c.). Also clonidine produced a dose-dependent (3–30 μg) antinociception following microinjection into the RVM. Microinjections of medetomidine into the cerebellum or the PAG produced an identical dose-response curve in the tail-flick test as that obtained following microinjection into the RVM. In spinalized rats the antinociceptive effect (tail-flick test) induced by medetomidine microinjected into the RVM was not less effective than in intact rats. Lidocaine (5%) or atipamezole (5 μg) microinjected into the RVM did not attenuate the antinociception induced by systemically administered medetomidine (100 μg/kg, s.c.). The adapting skin temperature of the tail was increased in a nonmonotonic fashion following medetomidine. The results indicate that the RVM is not a site which is critical for the α2-adrenergic antinociception. The antinociception following intracerebral microinjections of medetomidine into the RVM, PAG or the cerebellum in the current study can be explained by a spread of the α2-adrenoceptor agonist into the spinal level to activate directly spinal α2-adrenoceptors. Also, the antinociception following systemic administration of medetomidine can be explained by spinal α2-adrenergic mechanisms. The medetomidine-induced increase of the adapting skin temperature may have attenuated the medetomidine-induced increases in the response latencies to noxious heat. 相似文献
28.
The rostral ventromedial medulla (RVM) contains two classes of physiologically defined neurons, on-cells and off-cells, that are implicated in nociceptive modulation. In a continuing effort to detail the neural circuitry that underlies the activity of these two distinct neuronal types, the somatodendritic morphology of on- and off-cells was studied in the cat, rat, and ferret. In lightly anesthetized animals, on-cells increased and off-cells decreased their discharge rate during a withdrawal reflex evoked by noxious stimuli. Following their physiological characterization by using intracellular recording, on- and off-cells were injected with either horseradish peroxidase or biocytin and their somatodendritic arborizations were examined. Labeled on- and off-cells included fusiform and stellate cells of all sizes as well as large multipolar neurons. Although the somatic shape of both on- and off-cells in RVM was heterogeneous, off-cells tended to be fusiform neurons whose long axis was oriented mediolaterally. The dendritic domains of both on- and off-cells extended bilaterally past the lateral edge of the trapezoid body or pyramid and ventrally to, and sometimes including, the trapezoid body or pyramid. In contrast to their extensive mediolateral spread, the dendritic domains of both cell types were limited to the ventral half of the reticular formation and were compressed along the rostrocaudal axis. The dendritic arbor of individual on- and off-cells extended well beyond the cytoarchitectonic boundaries of any single nuclear region, within the domain delineated as the RVM. The spatial domains of the dendritic arbors of on- and off-cells are further evidence that the on- and off-cells throughout the RVM constitute an integrated unit in the modulation of nociceptive transmission. 相似文献
29.
30.
楔状核内微量注射谷氨酸对中缝大核痛放电的影响 总被引:4,自引:0,他引:4
用玻璃微电极细胞外记录法,探讨楔状核内注入胞体兴奋剂谷氨酸对中缝大核内痛兴奋性神经元痛放电的影响。结果表明,楔状核内注入谷氨酸可明显抑制中缝大核内痛兴奋性神经元痛放电。示楔状核内神经与抗伤害感受作用有关。 相似文献