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921.
The influence of ATP and AMP injected into the lateral cerebral ventricle in doses of 50, 100 and 200 mug on behavior in rats was studied. ATP in the doses administered had no effect on behavior of rats. AMP in these doses enhanced motor activity of the rats. Chemical sympathectomy by intracerebral injection of 6-hydroxy-dopamine did not affect the action of either of the compounds on behavior of rats. AMP potentiated the action of intracerbrally administered noradrenaline on behavior of the animals. 相似文献
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Histone neighbors in compact and extended chromatin have been investigated by cross-linking histones in nuclei and in nucleohistone extended with 6 M urea, using the bifunctional reversible reagent methyl-4-mercaptobutyrimidate (MMB). Similar histone dimers are found in both conformational states of chromatin. The dimers most frequently found are H2b-H2a, H2b-H3 and H3-H2a; dimers found less frequently are H3-H4, H3-H3 and H2b-H4. More H3-H3 is found in nuclei than in extended chromatin. H1 is found predominantly as poly-H1, although it can be cross-linked to H2b or H3. After reaction with MMB, native compact chromatin is no longer extendable in 6 M urea, which shows that the reagent is capable of linking together histones holding the chromatin in a compact conformation. Thus the histone propinquity in extended chromatin mimics and intimate histone associations in compact chromatin. 相似文献
924.
GH Roberson AK Patterson ME Deeb RH Maisel RC Bone 《Canadian Metallurgical Quarterly》1976,127(4):595-599
Fourteen cases of mucocele of the sphenoid sinus are reviewed to assess differentiating radiographic features. Recognition is usually possible using detailed tomography in the frontal, lateral, and submentovertex projections. Two constant findings were opacification of the sinus (usually bilateral) and expansion and thinning of the sinus walls. Contiguous opacification of the ethmoid sinuses was present in most cases, and pansinusitis was frequent. Distinction from intrasellar lesions is based on the absence of sellar enlargement. Early and correct diagnosis is important to prevent permanent visual loss and to assure appropriate surgical approach. 相似文献
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928.
Leiomyosarcoma of vascular origin are rare tumors arising most frequently from the inferior vena cava (IVC). We report on three patients one of whom underwent definitive resection. These tumors most commonly involve the upper segment of the IVC, and appear with manifestations of the Budd-Chiari syndrome. Lesions at this level are not amenable to surgical therapy. Tumors of the middle and lower segments of the IVC usually cause right-sided pain. Diagnosis is difficult, but is best approached preoperatively by angiography and vena cavography. Optimal therapy of lesions at these levels is surgical resection. Resection of the IVC below the hepatic veins is possible with renal function preserved by collateral drainage of the left renal vein. 相似文献
929.
Dheeraj Ahluwalia Michael J. Borrelli Kaleb Smithson Kamlakar P. Rajurkar Ajay P. Malshe 《CIRP Annals》2014,63(1):217-220
Thrombi, e.g. blood clots, in circulatory system pose acute health risk, globally. This research investigated roles of biodegradable starch slurry in advancing biomass machining efficiency. Hard clots (fibrin-rich) prepared from rabbit blood were exposed in vitro concomitantly to ultrasound (1 MHz) and starch slurry. Starch slurry particles (diameter ∼250 nm) yielded a 200% increase in material removal (sonothrombolysis) efficiency. Mechanistic participation of starch, a non-Newtonian material, at the interface of biomass-ultrasonic radiation is discussed. Overall in subtractive biomanufacturing, the role of biodegradable slurry is critical for enhancing material removal efficiency. 相似文献
930.
The work was carried out to investigate the relationship of non-cholinergic late slow excitatory potential (LS-EPSP) with 5-hydroxytryptamine (5-HT) and substance P (SP) in the neurons of the guinea pig celiac ganglion (CG) using intracellular electrodes in vitro. During repetitive stimulation of the splanchnic nerve (SN), LS-EPSP following a series of action potentials could be recorded in 161 out of 206 neurons (78.2%); Application of 5-HT and SP by superfusion or pressure ejection induced 5-HT depolarization in 102 out of 149 neurons (68.5%) and SP depolarization in 98 out of 188 neurons (52.1%), respectively; Most neurons, from which LS-EPSP could be recorded during stimulation of SN, were sensitive to 5-HT (73/88, 83.0%) and SP (68/114, 59.7%). However, only a small number of neurons not showing LS-EPSP during stimulation of SN were sensitive to 5-HT (10/26, 38.5%, P < 0.0001) and SP (11/36, 30.6%, P < 0.01). The results support the viewpoint that both 5-HT and SP are involved in the formation of LS-EPSP as transmitters; In addition, both effects of 5-HT and SP were examined in 133 neurons. There were 66 of these neurons (49.6%) to be sensitive to both 5-HT and SP, suggesting that there may be some functional relations between 5-HT and SP in the neurons of guinea pig CG. 相似文献