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991.
992.
T Hayashi S Asano M Mizutani N Takeguchi T Kojima K Okamura N Morita 《Journal of natural products》1991,54(3):802-809
A new tetracyclic diterpenoid, scopadulciol [3], together with 6-methoxybenzoxazolinone, glutinol, and acacetin, was isolated from the 70% EtOH extract of Scoparia dulcis collected in Taiwan. Its structure was elucidated to be 6 beta-benzoyl-12-methyl-13-oxo-9(12)a,9(12)b-dihomo-18-podocarpanol on the basis of spectral data. It mildly inhibited hog gastric H+, K(+)-ATPase. Examination of the inhibitory activities of derivatives of scopadulcic acid B [2], including 3, revealed that methylation of the carboxyl group and introduction of an acetyl group or oxime at C-13 or C-18 markedly enhanced the inhibitory activity, while debenzoylation reduced the activity. Among the 30 compounds tested, compound 12, a methyl ester of scopadulcic acid B [2], showed the most potent activity. 相似文献
993.
Satoru Hosoda Keitaro Kojima Motonobu Furuta 《Macromolecular chemistry and physics.》1986,187(6):1501-1514
The morphology of the lamellae in non-isothermally crystallized linear low-density polyethylene (LLDPE), conventional high-pressure low-density polyethylene (HP-LDPE), and a high-density polyethylene (HDPE) sample was investigated by transmission electron microscopy (TEM). LLDPE exhibits clearly two different types of lamellae, i.e., thick, long, and straight lamellae like those of HDPE, and thin, short, and curved lamellae which grow among the former ones. Also LLDPE shows the broadest distribution of the values for the lamella thickness among the three types of polyethylenes mentioned. The average lamella thickness decreases in the order HDPE > LLDPE > HP-LDPE. Fractions were used to study the effects of the kind and the degree of short chain branching (SCB) and of the molecular weight in the range from 4100 to 3,1·105. SCB has a predominant influence on the lamella thickness as well as on the shape, while the molecular weight does not largely affect lamella thickness but affects the shape of the lamellae. Further it was revealed from TEM observation that the isobutyl branch decreases lamella thickness more effectively than does the ethyl branch. This is in accordance with results from small-angle X-ray and differential scanning calorimetry measurements. 相似文献
994.
Slow reacting substance of anaphylaxis (SRS-A) has been shown to be one of the major mediators in hypersensitive reactions and to be composed of leukotriene (LT) C4, LTD4 and LTE4. In the present study, we examined the properties of SRS-A released from sensitized guinea pig lungs by antigen and SRS released from rat peritoneal exudate cells and from human leucocytes by ionophore A23187 (0.5 and 0.2 microgram/ml, respectively). By the incubation with SRS-A, SRS and LTs with arylsulfatase (type V) in pH 5.7 buffered solution at 37 degrees C for 30 min, SRS-A and LTD4 were greatly inactivated and rat SRS was slightly inactivated, but human SRS and LTC4 were not inactivated at all. The same results were obtained when aminopeptidase was used in place of arylsulfatase. Moreover, when SRS-A, LTC4 and LTD4 were incubated with 0.02 mg/ml of gamma-glutamyltranspeptidase (gamma-GTP) pH 8.0 buffered solution at 37 degrees C for 30 min, the activities of SRS-A and LTD4 were slightly decreased, but those of SRS and LTC4 were obviously potentiated. On the other hand, incubation with a large amount of gamma-GTP (0.2 mg/ml) a dose at which this enzyme preparation showed clear aminopeptidase activity, SRS-A, SRS, LTC4 and LTD4 were obviously inactivated. In addition, we found a peak of LTD4 in guinea pig SRS-A, that of LTC4 in human SRS, and that of LTC4 in rat SRS on high performance liquid chromatograms. From these results, we demonstrated that guinea pig lung SRS-A is mainly composed of LTD4, human leukocyte SRS is mainly LTC4, and rat peritoneal SRS is composed of both LTC4 and LTD4. The inactivation of LTD4 and SRS-A by arylsulfatase may be due to aminopeptidase contamination in the enzyme preparation. 相似文献
995.
Improved recombinant LC16m0 or LC16m8 vaccinia virus successfully expressing hepatitis B surface antigen 总被引:1,自引:0,他引:1
K Watanabe H Kobayashi K Kajiyama M Morita A Yasuda H Gotoh S Saeki M Sugimoto H Saito A Kojima 《Vaccine》1989,7(1):53-59
An attempt was made to develop a safe, efficacious live recombinant vaccine using low neurovirulent strains of vaccinia virus: LC16m0 (m0) or LC16m8 (m8). Recombinant vaccinia virus (RVV) was constructed by inserting the hepatitis B surface antigen (HBsAg) gene fused to a 7.5 kDa protein promoter (7.5 kDa promoter) within the vaccinia virus thymidine kinase (TK) gene using the m0 or m8 strain as vectors. These RVVs expressed significant amounts of HBsAg (1.1 microgram/2 X 10(5) cells) consisting of 24.5 and 28 kDa (glycosylated) proteins. HBsAg produced by RVV (vaccinia HBsAg) had physical properties very similar to plasma-derived HBsAg. Considering the safety of RVVs from m0 or m8 that have been constructed with HBsAg without the addition of a promoter and the high induction of anti-HBs antibody with RVV from m0 strain in rabbits, the RVVs constructed in the present study are likely to form the basis of a safe live RVV vaccine for hepatitis B virus (HBV). 相似文献
996.
T Kojima 《Seishin shinkeigaku zasshi》2001,103(9):688-692
997.
A 68-year-old male presented with neurological deterioration after a lucid interval following head trauma. Computed tomographic (CT) scans on admission demonstrated a subdural hematoma in the right frontotemporal region accompanied by subarachnoid hemorrhage in the right Sylvian and interhemispheric fissures. The subdural hematoma was removed via a right frontotemporoparietal craniectomy. However, immediate postoperative CT scans revealed hemorrhage in the third and both lateral ventricles, apparently separate from the primary hemorrhages. Decompressive rupture of damaged subependymal veins is suggested as the cause of the delayed traumatic intraventricular hemorrhage. 相似文献
998.
999.
A 37-year-old woman was admitted to the hospital with the complaint of progressive horizontal diplopia of six years' duration when viewing distant objects. On admission she had a slight left convergent strabismus. Homonymous diplopia was present beyond 50 cm and increased on distance fixation. Both eyes were fully mobile in the horizontal plane with a mild decrease in the velocity of horizontal eye movement to the left, and slight impairment of upward eye movement. The left eye did not fully adduct during convergence. The right pupil was slightly larger than the left. Prism cover test showed 6 delta esophoria at 30 cm and 14 delta esophoria at 5 m. The Hess chart showed a convergent deviation. MRI revealed a small right-side paramedian lesion of the midbrain tegmentum lying ventral to the aqueduct of Sylvius, at the level between the superior colliculi and the intercollicular area. A venous angioma with arteriovenous shunts in the right midbrain was diagnosed by angiography. We suggest that lesions that damage the divergence neurons in the tegmentum of the midbrain and also interrupt the supranuclear fibers having an inhibitory effect on the convergence neurons may produce homonymous diplopia on distant fixation combined with the esotropia. 相似文献
1000.