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41.
The neuropeptides Substance P, beta-Endorphin, Prolactin, Cholecystokinin, and Glucagon were investigated by means of Sternbergers PAP technique in the neuroepithelium of the Maculae utriculi and sacculi of the labyrinth of newborn guinea pigs. This brief report will show the localization of some neuropeptides in the neuroepithelium of the Maculae utriculi and sacculi. We could not find information about similar studies on this topic in the literature. In connection with investigations of the sensory apparatus of the inner ear we have recently presented neuropeptides evidence for the presence of certain peptides in the Ggl. spirale and the hair cells of the organ of Corti. With this paper we continue to report on neuropeptides in the labyrinth of the juvenile guinea pig as revealed by immunohistochemistry (Nowak et al., in press). 相似文献
42.
Barchet W Oehen S Klenerman P Wodarz D Bocharov G Lloyd AL Nowak MA Hengartner H Zinkernagel RM Ehl S 《European journal of immunology》2000,30(5):1356-1363
Lysis of infected cells by CD8(+) T cells is an important mechanism for the control of virus infections, but remains difficult to quantify in vivo. Here, we study the elimination kinetics of viral antigen-positive lymphocytes by antiviral CD8(+) T cells using flow cytometry and mathematical analysis. In mice acutely infected with lymphocytic choriomeningitis virus, more than 99.99 % of target cells were eliminated each day, corresponding to a half-life of 1.4 h. Even in mice exposed to virus 300 days previously, and with no ex vivo killing activity, 84 % of the target cells were eliminated per day. Unexpectedly, the elimination kinetics of antigen-positive lymphocytes was not significantly impaired in mice deficient in either perforin-, CD95 ligand- or TNF-mediated cytotoxicity. For viruses with a particular tropism for lymphocytes, such as Epstein-Barr virus or HIV, our results illustrate how effectively CD8(+) T cell-mediated elimination of target cells can potentially contribute to virus control and immunosuppression. 相似文献
43.
Depolarization thresholds for hippocampal damage, ischemic preconditioning, and changes in gene expression after global ischemia in the rat 总被引:1,自引:0,他引:1
Induced ischemic tolerance in rat hippocampus was investigated in a forebrain ischemia model of repeated 4-vessel occlusion (4-VO). Ischemic insult variability was reduced by the use of dc potential measurements to determine the duration of ischemic depolarization in hippocampus. The results demonstrate a depolarization threshold for ischemic injury to CA1 neurons of 4-6 min and a window for optimal preconditioning of 2.5-3.5 min. Levels of induced mRNAs encoding hsp72 and several immediate-early genes were also shown to vary with depolarization interval. Immediate-early genes were maximally induced after depolarization periods inducing optimal preconditioning, while hsp72 expression increased with insult severity over the range leading to neuron loss. These results are similar to those obtained in gerbil studies indicating that preconditioning does not require large increases in hsp72 expression, and demonstrate the fundamental comparability of rodent global ischemia models when monitored by this approach. 相似文献
44.
Ro 11-2465 (cianopramine, cyan-imipramine) and citalopram (CIT), putative antidepressant drugs, are very potent and selective 5-hydroxytryptamine (5-HT) uptake inhibitors in vitro. This study investigated the effects of these drugs and their desmethyl metabolites, Ro 12-5419 (desmethylcianopramine, cyan-desipramine) and desmethylcitalopram (DCIT), respectively, on the uptake of 5-HT and noradrenaline (NA) in vivo [protection against H 77/77 (4, alpha-dimethyl-metatyramine)-induced displacement of 5-HT and NA] and on related pharmacological activities. All the investigated drugs antagonized H 77/77-induced displacement of 5-HT in the rat brain, though the effects of the metabolites were considerably weaker than those of the parent compounds. The H 77/77-induced displacement of brain NA in rats and mice was antagonized only by Ro 12-5419 and Ro 11-2465. All the drugs potentiated the pressor response to 5-HT in pithed rats; however, Ro 12-5419 and particularly Ro 11-2465 could also block the response when used in higher doses (0.1 mg/kg). Only Ro 12-5419 and Ro 11-2465 were able to potentiate the pressor response to NA. Ro 12-5419 also potentiated thyrotropin releasing hormone (TRH) hyperthermia and antagonized reserpine hypothermia in mice; Ro 11-2465 potentiated the TRH hyperthermia only. CIT and DCIT were inactive in both these tests. Of all the four drugs only CIT and Ro 12-5419 considerably stimulated the hind limb flexor reflex in spinal rats. However, whereas the stimulatory effect of CIT was inhibited by the 5-HT antagonists metergoline and cyproheptadine, that of Ro 12-5419 was counteracted by the NA antagonist phenoxybenzamine only. Ro 11-2465, when used in low doses (ca. 1 mg/kg), slightly potentiated the flexor reflex, whereas in higher doses (4–16 mg/kg) it had no effect itself but antagonized the stimulatory action of the 5-HT agonists fenfluramine, quipazine and LSD. The results obtained indicate that Ro 11-2465 and CIT, as well as their desmethyl metabolites, are also potent 5-HT uptake inhibitors in vivo. However, only CIT and DCIT are concurrently devoid of effect on uptake of NA. In contrast, Ro 11-2465 and particularly Ro 12-5419 appear to also inhibit the uptake of NA. Moreover, Ro 11-2465 appears to block central and peripheral 5-HT receptors.The results were presented at the 14th CINP Congress, Florence, June 19–23, 1984 相似文献
45.
K Wisdom R M Nowak H H Richardson G B Martin F N Obeid M C Tomlanovich 《Annals of emergency medicine》1986,15(4):428-432
Traumatic pneumothorax is a common complication of the IV drug abusers in Detroit who utilize the "pocket shot" (the central approach to the internal jugular vein). Fourteen patients who sustained a total of 16 pneumothoraces (two with bilateral collapse) and who underwent catheter aspiration of a simple pneumothorax (CASP) were studied prospectively. The sizes ranged from less than 10% to 100%. In addition, there was one tension pneumothorax and one pneumomediastinum. The 16 CASP procedures produced 13 successful lung expansions (82%). The remaining three were treated with tube thoracostomy and admission. Twelve of the 13 patients in whom the procedure was successful returned for followup, and all of these had 100% continued full expansion. CASP appears to be a safe, efficacious, and cost-effective treatment for the drug abuser with simple traumatic pneumothorax. With the current pressures of cost containment, this less-invasive approach with outpatient management should be studied as initial potential treatment for any simple pneumothorax. 相似文献
46.
J. Z. Nowak A. Bogucki P. Liberski 《Journal of neural transmission (Vienna, Austria : 1996)》1986,65(3-4):187-192
Summary The histamine (Hi) content and the activity of L-histidine decarboxylase (HD) in brains of scrapie infected hamsters were measured. No significant changes in Hi levels in particular brain areas were found when compared to controls. Decreased activity of HD was found in hypothalamus (p<0.02). Increased activity of the enzyme was observed in rest of brain, which consisted mainly of thalamus and striatum (p<0.05). 相似文献
47.
48.
Botanicals in Postmenopausal Osteoporosis 总被引:1,自引:0,他引:1
Osteoporosis is a systemic bone disease characterized by reduced bone mass and the deterioration of bone microarchitecture leading to bone fragility and an increased risk of fractures. Conventional anti-osteoporotic pharmaceutics are effective in the treatment and prophylaxis of osteoporosis, however they are associated with various side effects that push many women into seeking botanicals as an alternative therapy. Traditional folk medicine is a rich source of bioactive compounds waiting for discovery and investigation that might be used in those patients, and therefore botanicals have recently received increasing attention. The aim of this review of literature is to present the comprehensive information about plant-derived compounds that might be used to maintain bone health in perimenopausal and postmenopausal females. 相似文献
49.
Curcumin is one of the most frequently researched herbal substances; however, it has been reported to have a poor bioavailability and fast metabolism, which has led to doubts about its effectiveness. Curcumin has antioxidant and anti-inflammatory effects, and has demonstrated favorable health effects. Nevertheless, well-reported in vivo pharmacological activities of curcumin are limited by its poor solubility, bioavailability, and pharmacokinetic profile. The bidirectional interactions between curcumin and gut microbiota play key roles in understanding the ambiguity between the bioavailability and biological activity of curcumin, including its wider health impact. 相似文献
50.
应用四唑盐比色法对5种骨水泥的细胞毒性的测试 总被引:4,自引:1,他引:3
0 引言 应用细胞培养法对牙科材料的生物相容性进行评价是一种简便、有效、经济的方法 .近年来 ,国内外有许多学者报道用 MTT检测细胞活性 ,并认为用 MTT法可以代替活细胞计数、同位素标记进行细胞毒性试验 .我们应用 MTT法对 5种骨水泥的细胞毒性进行了评价 ,并对有关问题进行了讨论 .1 材料和方法1.1 测试材料 1号 :生物水泥 ,2号 :羟基磷灰石人工骨 ,3号 :氰基丙烯酸酯骨水泥 1号 (自制 ) ,4号 :氰基丙烯酸酯骨水泥 2号 (自制 ) ,5号 :氰基丙烯酸酯骨水泥 3号 (自制 ) .阴性对照采用珊瑚 ,阳性对照采用聚氯乙烯 .1.2 实验步骤… 相似文献