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31.
Kappa opioid receptors stimulation with U50,488 is known to modulate behaviors during the early postnatal period, but the specific neuroanatomical locus of many of these effects is unexplored. In the present study, we infused U50,488 into the midbrain periaqueductal gray (PAG) and investigated the effects of this drug on behavior and heart rate of 1-, 2-, and 3-week-old rats. U50,488 increased activity most potently in 1- and 2-week-old subjects. Ultrasonic vocalization (USV) production was increased in 1-week-old subjects, but not in 2- or 3-week-old pups. Heart rate changes were similarly seen in younger aged subjects. At 1 week, U50,488 decreased heart rate, but at 2 weeks it increased heart rate. There was no effect of this drug on heart rate at 3 weeks. At 1 week, USVs were more potently elicited from dorsal than lateral PAG infusion sites. No other site-specific effects within the PAG were seen. The age-related decline in behavioral effects elicited by U50,488 is consistent with other published reports, and to the extent that kappa receptor activity mediates infant separation responses, implicates the PAG as a modulator of those responses. 相似文献
32.
目的:探讨PSA、fPSA与前列腺癌骨转移的关系.方法:以核素全身骨扫描为金标准,回顾性分析了化学发光法测定的128例前列腺癌患者血清PSA、fPSA水平与骨转移的关系.结果:骨转移患者PSA明显高于非转移患者,fPSA明显低于非转移患者;PSA>20μg/L,特别是同时伴有fPSA/PSA<0.18者骨转移的阳性率极高.结论:对于前列腺癌患者PSA<20μg/L者密切随访PSA;PSA>20μg/L者骨转移可能性极大,应行骨扫描确诊;PSA、fPSA联检对诊断前列腺癌骨转移具有重要意义. 相似文献
33.
Renske Oegema George McGillivray Richard Leventer Anne‐Gaëlle Le Moing Nadia Bahi‐Buisson Angela Barnicoat Simone Mandelstam David Francis Fiona Francis Grazia M. S. Mancini Sanne Savelberg Gijs van Haaften Kshitij Mankad Maarten H. Lequin 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(4):627-637
34.
Yuan B. Peng Qing Lin W. D. Willis 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,114(3):561-570
The effects of a protein kinase C (PKC) activator, 12-O-tetradecanoylphorbol-13-acetate (TPA), on the activity and periaqueductal gray (PAG)-induced inhibition of rat dorsal horn
neurons of the lumbar spinal cord were tested. A microdialysis fiber was placed through the dorsal horn for the purpose of
local application of pharmacological agents. Extracellular single-unit recordings from dorsal horn neurons were made near
the microdialysis fiber. TPA was tested on nociceptive dorsal horn cells. There was a significant increase in the background
activity and responses to ”brush”, with no changes in responses to pressure and pinch stimuli. TPA also significantly blocked
the PAG-induced inhibition of responses to brush, press, and pinch. These effects were eliminated by coadministration of the
PKC inhibitor NPC-15437. The solvent, which contained dimethyl sulfoxide, was also tested for its effect on the responses
to peripheral mechanical stimuli and PAG-induced inhibition of the dorsal horn neurons. There were no significant changes.
This experiment suggests that activation of the PKC second messenger system might increase the activity of dorsal horn neurons
and their responses to peripheral stimuli; in addition, the phorbol ester attenuated the PAG-induced descending inhibition
of the dorsal horn neuron activity.
Received: 15 May 1996 / Accepted: 14 November 1996 相似文献
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Thierry Janssen MD Michel Petein MD Roland van Velthoven MD Patrick van Leer MD Marc Fourmarier MD Juan-Pablo Vanegas MD Andre Danguy PhD Claude Schulman MD Jean-Lambert Pasteels MD Robert Kiss PhD 《Human pathology》1996,27(12):1341-1347
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors. 相似文献
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本文用PAP和ABC法对3例生后1—2天新生儿中脑导水管周围灰质(PAG)内P物质、亮氨酸脑啡肽、5-羟色胺样成分的分布进行了观察。发现P物质样阳性胞体主要位于PAG的中、尾段,分为位于腹外侧区的腹侧群和位于腹外侧区与背外侧区交界处的外侧群等两群。其阳性纤维和终末以背侧区为最密。亮氨酸脑啡肽样阳性胞体也出现于PAG中、尾段的各个区内,以腹外侧区数量为多,其阳性纤维及终末也以腹外侧区最密集。5-羟色胺样阳性胞体集中在PAG中、尾段的腹外侧区,其阳性纤维及终末主要分布于PAG的内侧区。本文还对此三种物质与镇痛机制的关系进行了讨论。 相似文献
40.
Neural transection of the dorsal extrahypothalamic descending afferents by means of an L-shaped Halász knife at the anterior commissure (anterior roof deafferentation. ARD) markedly potentiated the display of lordosis and soliciting behaviors. Bilateral lesions of the ventromedial hypothalamus (VMH) attenuated lordotic activity in the ARD sham females but not in the ARD females. In contrast, the lesions in the pontine central gray concurrently with ARD effectively inhibited the display of lordosis but not soliciting behaviors. These results suggest that the VMH may not be a primary focus of the dorsal extrahypothalamic inhibitory influence on lordosis. The influence of this inhibitory system seems to be dominant in regulating the expression of lordosis behavior, compared to that of the hypothalamic lordosis facilitating system. Furthermore, the dorsal extrahypothalamic inhibitors influence which could be removed by ARD must be modified by the neural mechanism in the lower brain stem in which the pontine central gray may be actively involved. 相似文献