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81.
Ognen A. C. Petroff Richard H. Mattson Kevin L. Behar Fahmeed Hyder Douglas L. Rothman 《Annals of neurology》1998,44(6):948-952
Homocarnosine, a dipeptide of γ-aminobutyric acid (GABA) and histidine, is thought to be an inhibitory neuromodulator synthesized in subclasses of GABAergic neurons. Homocarnosine is present in human brain in greater amounts (0.4–1.0 μmol/g) than in other animals. The antiepileptic drug vigabatrin increases human cerebrospinal fluid homocarnosine linearly with daily dose. By using 1H nuclear magnetic resonance spectroscopy, serial occipital lobe GABA and homocarnosine concentrations were measured in 11 patients started on vigabatrin. Daily low-dose (2 g) vigabatrin increased both homocarnosine and GABA. Larger doses of vigabatrin (4 g) further increased homocarnosine but changed GABA levels minimally. Seizure control improved with increasing homocarnosine and GABA concentrations. Patients whose seizure control improved with the addition of vigabatrin had higher mean homocarnosine, but the same mean GABA concentrations, than those whose seizure control did not improve. Increased homocarnosine may contribute to improved seizure control. 相似文献
82.
Doz. Dr. F. Helmer OA Dr. E. Domanig Jr. Dr. W. Weißenhofer Dr. E. Wolner 《European Surgery》1970,2(6):177-179
Zusammenfassung Es wird über 6 Patienten mit totalem Herzblock berichtet, bei welchen nach einer Schrittmacherimplantation ein allgemeinchirurgischer
Eingriff ausgeführt wurde. An Hand der eigenen F?lle wird auf die Problematik solcher Eingriffe eingegangen.
Summary A report is given about 6 patients carrying implanted pacemakers for complete heartblock, who had to undergo different major surgical procedures. The problems involved are discussed.相似文献
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86.
Margaret G. Petroff Antoine Perchellet 《American journal of reproductive immunology (New York, N.Y. : 1989)》2010,63(6):506-519
Citation Petroff MG, Perchellet A. B7 family molecules as regulators of the maternal immune system in pregnancy. Am J Reprod Immunol 2010 Placental and fetal growth and development are associated with chronic exposure of the maternal immune system to fetally derived, paternally inherited antigens. Because maternal lymphocytes are aware of fetal antigens, active tolerance mechanisms are required to ensure unperturbed progression of pregnancy and delivery of a healthy newborn. These mechanisms of tolerance may include deletion, receptor downregulation, and anergy of fetal antigen‐specific cells in lymphoid tissues, as well as regulation at the maternal–fetal interface by a variety of locally expressed immunoregulatory molecules. The B7 family of costimulatory molecules comprises one group of immunoregulatory molecules present in the decidua and placenta. B7 family members mediate both inhibitory and stimulatory effects on T‐cell activation and effector functions and may play a critical role in maintaining tolerance to the fetus. Here, we review the known functions of the B7 family proteins in pregnancy. 相似文献
87.
Swen Hesse Franziska Moeller David Petroff Donald Lobsien Julia Luthardt Ralf Regenthal Georg-Alexander Becker Marianne Patt Eva Thomae Anita Seese Philipp M. Meyer Florian Then Bergh Osama Sabri 《European journal of nuclear medicine and molecular imaging》2014,41(5):827-835
Purpose
Modulation of the immune system by the CNS may involve serotonergic regulation via the brain serotonin transporters (SERT). This regulation may be disturbed in patients with CNS disorders including multiple sclerosis (MS). Central serotonergic mechanisms have not been investigated in MS by in vivo imaging. The objective of the study was to assess the availability of SERT in antidepressant-naive patients with MS by means of PET.Methods
Included in this study were 23 patients with MS and 22 matched healthy volunteers who were investigated with PET and the SERT-selective marker [11C]DASB, and distribution volume ratios were determined. Clinical assessment of the patients included the expanded disability status scale, the MS fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and the Beck Depression Inventory (BDI). The PET data were analysed with both volume-of-interest and voxel-based analyses to determine regional SERT availability.Results
Patients had lower SERT availability in the cingulate cortex, the thalamus and the insula, and increased availability in the orbitofrontal cortex. Patients with relapsing/remitting MS tended to have lower SERT in the hippocampus, whereas patients with primary progressive disease showed increased SERT availability in prefrontal regions. There was a positive correlation between SERT availability in the insula and both depression and fatigue scores (r?=?0.56 vs. BDI, p?=?0.02; r?=?0.49 vs. WEIMuS, p?=?0.05).Conclusion
Serotonergic neurotransmission in MS patients is altered in limbic and paralimbic regions as well as in the frontal cortex that this appears to contribute to psychiatric symptoms of MS. 相似文献88.
SO Oyedemi EA Adewusi OA Aiyegoro DA Akinpelu 《Asian Pacific Journal of Tropical Biomedicine》2011,1(5):353-358
Objective
To investigate the antidiabetic properties of aqueous extract of stem bark of Afzelia africana (A. africana) and its beneficial effect on haematological parameters in streptozotocin induced diabetic rats.Methods
A total of 30 rats including 24 diabetic and 6 normal rats were used for this study. Diabetes was induced in male Wistar rats by intraperitoneal injection of streptozotocin. After being confirmed diabetic, animals were orally treated with distilled water or extracts at 100 or 200 mg/kg body weight daily for 10 days. The haematological parameters including red blood and white blood cells and their functional indices were evaluated in diabetic treated groups compared with the controls.Results
The extract significantly reduced the blood glucose levels while the best result was obtained at 200 mg/kg body weight. The feed and water intake in diabetic rats were significantly reduced while weight loss was minimized at both dosages. Similarly, the levels of red blood, white blood cells and their functional indices were significantly improved after extract administration at both doses.Conclusions
It can be concluded that the aqueous extract of bark of A. africana possesses antihyperglycemic properties. In addition, the extract can prevent various complications of diabetes and improve some haematological parameters. Further experimental investigation is needed to exploit its relevant therapeutic effect to substantiate its ethnomedicinal usage. 相似文献89.
90.
McIntire RH Morales PJ Petroff MG Colonna M Hunt JS 《Journal of leukocyte biology》2004,76(6):1220-1228