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Shigeki Nagao Yoshihiro Kawabata Takashige Nishikawa Haruhiko Takada 《Microbiology and immunology》1995,39(12):1011-1014
Guinea pigs immunized with Freund's complete adjuvant received challenge injection of the purified protein derivative of Mycobacterium tuberculosis in the flanks and the corneas to prepare delayed-type hypersensitivity (DTH) reactions. The animals were injected subcutaneously with lipopolysaccharide (LPS) or a synthetic lipid A (LA-15-PP). At the skin site primed with DTH reaction, increased swelling and hemorrhagic reaction followed by a definite necrotic reaction occurred. Severe corneal reactions were also observed in the animals. These findings indicate that bacterial endotoxin modulates DTH reactions and induces severe inflammatory reactions. 相似文献
74.
Thirty-eight strains of 12Microsporum and 10Arthroderma (Nannizzia) species were investigated by analysis of mitochondrial DNA with 6 restriction enzymes, and classified into 13 genetic groups. The phylogenetic tree of the 13 groups thus established was constructed. On the tree,M. audouinii, M. langeronii, M. rivalieri, M. distortum, M. equinum, M. ferrugineum andA. otae comprise one genetic group and are suggested to be the same species.A. gypseum, A. fulvum, M. duboisii, M. ripariae, A. incurvatum, A. persicolor andA. obtusum are clustered on one of five boughs of the tree indicating their close relation.A. racemosum andA. cajetani are also closely related. 相似文献
75.
To determine whether the acid phosphatase in Micrococcus denitrificans participates in hydrolysis of thiamine phosphate in the synthesis of thiamine pyrophosphate, acid phosphatase was purified 280-fold by conventional procedures, which removed thiamine phosphate phosphatase completely. Studies showed that this acid phosphatase is a different protein from thiamine phosphate phosphatase and that it has no binding site for thiamine phosphate on its active site. 相似文献
76.
Intraventricular administration of muscimol (25–100 ng) and intravenously applied aminooxyacetic acid (2.5–10 mg/kg) depressed the crossed extensor reflex response in a dose-dependent manner. The inhibitory effects of both drugs were clearly antagonized by a subconvulsive dose of bicuculline. A very small dose of bicuculline (10–40 μg/kg, i.v.) produced a dose-related enhancement of the crossed extensor reflex response without any sign of convulsion. These results suggest that the crossed extensor reflex response is very sensitive to GABAergic drugs and central GABAergic mechanisms play a role in the modulation of the crossed extensor reflex response. 相似文献
77.
Junichi Kitajima Tetsuya Komori Toshio Kawasaki Hans-rolf Schulten 《Phytochemistry》1982,21(1):187-192
From the aerial parts of Fritillaria thunbergii, three glycosidal Solanum alkaloids (basic steroid saponins) were isolated together with minor 相似文献
78.
A new germacranolide isolated from M. sieboldii was shown to be 15-acetoxycostunolide by spectroscopic and chemical methods. 1H NMR spin decoupling and NOE experiments in the presence of a lanthanide shift reagent were used for structure elucidation. 相似文献
79.
Kozo Hayashi Kazuo Yamada Keiji Ohe Akima Miyoshi Takashi Kawasaki 《生物化学与生物物理学报:生物膜》1980,596(3):414-419
The effect of amytal on energy metabolism and acid secretion in an isolated gastric mucosa of the guinea-pig were studied. Determination of adenine nucleotides, creatine phosphate, pyruvate and lactate in the gastric mucosa showed that amytal depressed the levels of ATP, creatine phosphate and energy charge with elevation of the AMP and pyruvate levels. This treatment inhibited concomitantly acid secretion and active chloride transport detected by short circuit current. The addition of menadione with ascorbate to the medium in the presence of amytal partially restored ATP and energy charge levels and also induced a partial recovery of acid secretion and active chloride transport. These results suggest that ATP is a direct energy donor for acid secretion in the gastric mucosa of the guinea-pig. 相似文献
80.
The amounts of d-alanine derivatives, γ-l-glutamyl-d-alanine and N-malonyl-d-alanine, increase rapidly during the early growth of pea seeds. Pyruvate-[1?14C], l-alanine-[U?14C], d-alanine-[U?14C], l-alanine-[15N] and 15NH4Cl were therefore fed to the seedlings and the incorporation investigated. Labelling results revealed that pea seedlings can utilize these erogenous compounds to form d-alanine and that labelled l-alanine is effectively converted to the d-enantiomer with retention of 14C and, largely, 15N label. Enzyme analyses in vitro provided additional evidence that the extract of pea seedlings catalyzes the direct conversion of l-alanine to d-alanine. The data suggest that the de novo synthesis of d-alanine in pea seedlings occurs by a racemase reaction. 相似文献