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31.
The respiratory region of the nasal mucosa is innervated by the ethmoidal nerve. Chemical nociceptive stimulation of this area leads to upper airway reflexes that prevent access of noxious substances to the respiratory tract and the lungs. In the present study we examined the localization of the cell bodies of the respective primary afferent fibres within the trigeminal ganglion, as well as their central projections. In 25 rats a horseradish peroxidase-wheat germ agglutinin gel was applied to the right nasal cavity. The animals were killed after 48-72 h. For visualization of the tracer the tissue was processed according to the tetramethylbenzidine method. In the trigeminal ganglion almost all labelled cell bodies were localized in a medial band immediately caudal to the entrance of the ophthalmomaxillary branch. Transganglionic projections to the trigeminal brainstem nuclear complex were only localized in the superficial laminae of the subnucleus caudalis and in the subnucleus interpolaris, areas known to be involved in processing of nociceptive information. An additional labelled terminal field was observed in the interstitial subnucleus of the nucleus tractus solitarius, which is involved in respiratory control. These results are in favour of the hypothesis that the ethmoidal nerve in rat constitutes the afferent limb of protective upper airway reflexes since it transmits mainly nociceptive information. 相似文献
32.
Menno van Gameren Maarten Witsenburg Johanna J M Takkenberg Derize Boshoff Luc Mertens Anton M van Oort Dani?l de Wolf Matthias Freund Narayanswani Sreeram Regina B?kenkamp Melle D Talsma Marc Gewillig 《European heart journal》2006,27(22):2709-2715
AIMS: Stenting has become an established interventional cardiology procedure for congenital heart disease. Although most stent procedures are completed successfully, complications may occur. This multicentre study evaluated early complications after stenting in patients with congenital heart disease, including potential risk factors. METHODS AND RESULTS: In this combined Dutch-Belgian retrospective study, 309 consecutive patients had undergone 366 catheterizations and received 464 stents in 13 different anatomical positions (418 sites). Seventy-two stenting-related complications (19%) occurred, of which 24 (5.7%) were major. Seven procedure-related deaths were documented (2.3%). Stent malpositioning and embolization were most common (7.7%). The use of non-premounted stents tended to be associated with higher complication rates. Centre inexperience with stenting and stenting of native vs. post-surgical stenosis tended to be associated with increased major complication rates. CONCLUSION: After stenting, complications are common for congenital heart disease. The vast diversity of stenotic sites combined with relatively small patient populations makes these procedures sensitive to complications. Combining operator experience may reduce the risks of stenting in congenital heart disease. The availability of premounted stents for greater vessel diameters will likely reduce incidences of stent migration and embolization. 相似文献
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The authors present an account on a 12-year-old girl with ectomesodermal dysgenesis of the Rieger type syndrome. The disease was manifested at the age of nine months by transient diffuse corneal opacity, while the intraocular pressure was normal. In addition to typical corneal changes and changes in the angle of the chamber other associated somatic symptoms included megalocornea, high myoptic astigmatism, cleft soft palate, hypoplasia of the upper jaw, partial anodontia, marked thoracic kyphosis, scoliosis, generalized hypermobility and taxicity of the joints and torticollis. Examination revealed an uncommon pathological karyotype 46, XX, t/1,4 (p36, q23). Cytogenetic examination of the parents and siblings of the proband did not disclose any numerical or structural aberrations. The authors reflect on possible causes of the development of the disease and on the differential diagnosis. 相似文献
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An aqueous Beta vulgaris extract was repeatedly administered to mice by intranasal (i.n.) instillation, prior to i.n. inoculation of influenza virus A/PR/8/34 (H1N1). The extract conferred a partial protection against the experimental influenza infection: there was a significant decrease in the hemagglutination titers recorded in mouse lung homogenates, a decrease in mortality rate and an increase in the mean survival time as compared with the untreated, virus-inoculated controls. 相似文献
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George G. J. M. Kuiper Petra E. de Ruiter J. Anton Grootegoed Albert O. Brinkmann 《Molecular and cellular endocrinology》1991,80(1-3):65-73
Androgen receptor synthesis and modification were studied in the human LNCaP cell line. Immunoblotting with a specific polyclonal antibody showed that the androgen receptor migrated as a closely spaced 110–112 kDa doublet on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels. Most of the receptor protein is present in the higher molecular mass form. Pulse labelling experiments with [35S]methionine showed that the androgen receptor is synthesized as a single 110 kDa protein which is rapidly converted to a 112 kDa protein. Alkaline phosphatase treatment of cytosols from [35S]methionine pulse labelled cells caused a gradual elimination of the 112 kDa isoform with a concomitant increase of the 110 kDa isoform. This indicates that the observed 110 to 112 kDa upshift of the newly synthesized androgen receptor reflects receptor phosphorylation. Both isoforms can bind hormone and can undergo a hormone dependent transformation to a tight nuclear binding form, indicating that the 110 to 112 kDa conversion is not an obligatory step for hormone binding or receptor transformation. 相似文献
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The potential role of the heparin-binding growth factor pleiotrophin in breast cancer 总被引:1,自引:0,他引:1
Summary We propose that the secreted protein pleiotrophin (PTN) is a major factor in the malignant progression of breast cancer. This hypothesis is based on the growth-stimulatory effects of PTN on cellsin vitro andin vivo and on its high levels of expression in 60% of tumor samples from breast cancer patients. The stimulation of proliferation and tube formation of endothelial cells by PTN suggests that it can serve as an angiogenesis factor during tumor growth. We hypothesize that PTN has the potential to support growth of breast cancer at its primary site and to enhance the ability of tumor cells to metastasize. Furthermore, we suggest that specific endocrine signals interact to regulate the expression of PTNin vitro andin vivo. Finally, we propose that understanding the functions of PTN and its hormonal regulation can lead to the development of novel therapeutic strategies for breast cancer. 相似文献