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991.
We examined the relationships between the relaxation mediated by beta-adrenoceptor and either the associated cyclic AMP production or the activation of cyclic AMP-dependent protein kinase (A-PK) in canine saphenous and portal veins. In the saphenous vein constricted with methoxamine, isoproterenol caused concentration-dependent relaxation (maximum relaxation 92.7%), and concomitant increases in cyclic AMP and A-PK activity ratio (from 52.8 to 73.5%). The portal vein was only slightly relaxed by isoproterenol (14.7% in the longitudinal strips) after constriction with methoxamine, while cyclic AMP and A-PK activation increased significantly. Isoproterenol markedly activated A-PK of the portal vein after KCl constriction (from 52.6 to 74.6%) but the maximum relaxation was only slight (13.3%). The portal vein also showed a smaller relaxation response to either forskolin or dibutyryl cyclic AMP than the saphenous vein. These results indicated that the relationship between the relaxation response to isoproterenol and either cyclic AMP production or A-PK activation was different in the saphenous and portal veins. 相似文献
992.
993.
994.
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996.
本文应用核磁共振法(NMR)测定了几种混合体系的 HLB 值与混合体系中各组分的 HLB 值。实验结果表明,混合体系中各组分在核磁共振图谱中的积分曲线高度也具有加和性。混合体系的 HLB 值是体系中各组分 HLB 值的加权平均值。因此,对混合体系的 HLB 值可以应用 NMR 法直接测定,也可应用 NMR 法测定各组分的 HLB值,通过计算求得,计算值与实测值完全一致。 相似文献
997.
A. Sh. Oganisyan A. S. Noravyan I. A. Dzhagatspanyan I. M. Nazaryan A. G. Akopyan 《Pharmaceutical Chemistry Journal》2007,41(11):588-590
New methods for the synthesis of 4-substituted 6,7-dihydro-7,7-dimethyl-5-oxo-9H-pyrano-[4′,3′: 4,5]-thieno[3,2-e]imidazo[1,2-a]pyrimidines
and their hydrochlorides are developed. The anticonvulsant and tranquilizer properties of newly synthesized compounds have
been studied.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 11, pp. 22–24, November, 2007. 相似文献
998.
Autophagy-mediated chemosensitizing effect of the plant alkaloid voacamine on multidrug resistant cells. 总被引:1,自引:0,他引:1
S Meschini M Condello M Marra G Formisano E Federici G Arancia 《Toxicology in vitro》2007,21(2):197-203
In our previous studies, voacamine, a bisindolic alkaloid extracted from Peschiera fuchsiaefolia, was examined for its possible capability of enhancing the cytotoxic effect of doxorubicin (DOX) on multidrug resistant (MDR) human osteosarcoma cells (U-2 OS-R). Voacamine induced in resistant cells a significant increase of drug retention and intranuclear location which became comparable to those observed in the parental sensitive counterparts (U-2 OS-WT). In the present study, the cell survival analysis and the electron microscopic observations confirmed the evident cytotoxicity of DOX on MDR cells after pre-treatment with the plant extract. Moreover, an increase of the reactivity of P-glycoprotein (P-gp) with the monoclonal antibody UIC2, which recognizes an epitope of the drug transporter in its functional conformation, was revealed, demonstrating that voacamine is a substrate of P-gp, thus acting as a competitive antagonist of the cytotoxic agent. Moreover, to investigate if the enhancement of the cytotoxic effect induced by voacamine could be due to an apoptotic process, we carried out the analysis of cell morphology after Hoechst staining and the quantification of apoptosis by Annexin V-FITC assay. These evaluations showed a very low rate of apoptosis in U-2 OS-R cells treated with voacamine and DOX given in association. In addition, the combined treatment induced ultrastructural modifications suggestive of autophagic cell death. In particular, transmission electron microscopy observations revealed the presence of numerous lysosomes and the formation of a large number of autophagosomes containing residual digested material. In conclusion, these findings seem to indicate that voacamine is capable of enhancing the cytotoxic effect of DOX on MDR cells by favouring a lethal autophagic process. 相似文献
999.
1000.
T. Pinzer M. Reiß H. Bourquain K. G. Krishnan G. Schackert 《Acta neurochirurgica》2006,148(10):1085-1090
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant
forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the
often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological
signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively
or on histological examination.
We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor
of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was
immune competent and had no past history of sinusitis.
The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity
of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype
of invasive fungal sinusitis and the degree of tissue invasion. 相似文献