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111.
BACKGROUND: To develop a supplementary diagnostic method for endometrial cancer by measuring the reactivity of various endometrial lesions with two monoclonal antibodies. METHODS: We investigated the reactivity of various endometrial lesions with two monoclonal antibodies (MSN-1 and MSN-3) by flow cytometry (one-color and two-color methods). RESULTS: The two-color method appeared to be suitable for use in place of simultaneous performance of the one-color methods with MSN-1 and MSN-3. The positivity rate for normal endometrium was 16.0% with the two-color method, which was lower than the rate of 30.0% obtained with concomitant used of the one-color methods. The positivity rate for endometrial cancer was high, 84.0%, with the two-color method. The positivity rate was 85.7% for well-differentiated endometrial cancer, 71.4% for moderately differentiated cancer, and 100.0% for poorly differentiated cancer; thus, the rate was high irrespective of the cellular differentiation. CONCLUSIONS: The two-color method is more useful than the one-color method as a supplementary diagnostic procedure for endometrial cancer.  相似文献   
112.
2-Iodonoraristeromycin, 2-iodoaristeromycin and related analogs were synthesized to investigate their inhibitory activities against human and Plasmodium falciparum S-adenosyl-L-homocysteine hydrolases.  相似文献   
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114.
A simple major protease, secreted into the medium during growth of Tetrahymena pyriformis strain W, has been purified about 4000-fold by (NH4)2SO4 precipitation, ion-exchange chromatography, gel filtration and affinity chromatography on organomercurial-Sepharose. The purified protease was homogeneous as judged by polyacrylamide gel electrophoresis and was a monomeric protein with a molecular weight of 22 000-23 000. Amino acid analysis showed that the enzyme was rich in acidic amino acids. In addition, the purified Tetrahymena protease consists of multiple forms with isoelectric point between pH 5.3 and 6.3. Optimum activity of the purified enzyme was in the pH range 6.5-8.0 with alpha-N-benzoyl-DL-arginine-p-nitroanilide and with azocasein, while it was in the lower pH range (4.5-5.5) for denatured hemoglobins. The purified enzyme was inhibited by compounds effective against thiol proteases. Leupeptin and chymostatin were potent inhibitors but pepstatin was without effect. This enzyme is similar to cathepsin B and appears to be a major proteolytic enzyme in Tetrahymena.  相似文献   
115.
Oxygen consumption rates during embryonic and the first 38 days of larval development of the striped mullet were measured at 24° C by differential respirometry. Measurements were obtained at the blastula, gastrula and four embryonic stages, and at the yolk-sac, preflexion, flexion and post-flexion larval stages.
Oxygen uptake rates of eggs increased linearly from 0.024 μl O2 per egg h-1 (0·323 μl O2 mg-1 dry wt h-1) by blastulae to 0·177 μlO2 per egg h-1 (2·516 μlO2mg 1dry wth-1) by embryos prior to hatching. Respiration rates did not vary significantly among four salinities (20,25, 30, 35%0).
Larval oxygen consumption increased in a curvilinear manner from 0·243 μl O2 per larva h-1 shortly after hatching to 18·880 μl O2 per larva h-1 on day 38. Oxygen consumption varied in direct proportion to dry weight. Mass-specific oxygen consumption rates of preflexion, flexion, and postflexion larvae did not change with age (10·838 μl O2 mg 1dry wt h-1).
Larval oxygen consumption rates did not vary significantly among salinities 10–35%. Acute temperature increases elicited significant increases in oxygen consumption, these being relatively greater in yolk-sac larvae ( Q10 = 2·75) than in postflexion larvae ( Q10 = 1·40).  相似文献   
116.
1. A serine protease of hepatoma 8999, isolated in the mitochondrial fraction, was purified and crystallized. The purified enzyme was apparently homogeneous on ultracentrifugal analysis and polyacrylamide disc gel electrophoresis. The ratio of absorbance at 280 nm and 260 nm, A280/A260, was 1.90 and its absorption coefficient, A280 1% was 10.5 cm-1 estimated from dry weight measurements. Its S20, w value was 2.23 S and its molecular weight was estimated to be 24000 +/- 1000. The enzyme contained twice as much lysine, arginine and histidine as chymotrypsinogen did, but had a very similar amino acid composition to serine protease from skeletal muscle. Its isoelectric point was pH 10.6. 2. The substrate specificity of the enzyme was the same as that of chymotrypsin A. Its Km and kcat values for N-acetyl-L-tyrosine ethyl ester, N-acetyl-L-phenylalanine ethyl ester and N-acetyl-L-tryptophan ethyl ester were 0.35 mM and 10.69 s-1, 0.38 mM and 10.7 s-1, and 0.11 mM and 11.8 s-1, respectively. Its activity was completely inhibited by phenylmethylsulfonyl fluoride and partially inhibited with tosylphenylalanine chloromethyl ketone. 3. The enzyme was shown to be located in different granules from the intracellular particules (light and heavy mitochondrial fraction) by sucrose density gradient centrifugation, and it was stained in mast cells of the hepatoma 8999 by the immunofluorescent technique. 4. Serine protease is present in different amounts in various organs of rat and the enzyme from hepatoma 8999 gave a single band that fused completely with those of the enzymes from skeletal muscle, heart, liver and kidney, respectively, on Ouchterlony double-diffusion analysis using antiserum to the crystalline enzyme of hepatoma 8999, but the enzyme from small intestine did not react with the antiserum.  相似文献   
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118.
The silkworm Bombyx mori 30-kDa lipoproteins (6G1 and 19G1), major components of the hemolymph, were shown to bind to glucans. 6G1 apolipoprotein was expressed as a fusion protein with glutathione S-transferase in Escherichia coli and assayed for its binding activity. The purified recombinant 6G1 apolipoprotein specifically bound to beta-glucan, but not to chitin, mannan, peptidoglycan, or oligosaccharide chains on glycoproteins. The beta-glucan binding of the recombinant 6G1 was inhibited by laminaribiose and laminarin, a soluble glucan, but not by lipopolysaccharide or insect blood sugar, trehalose at physiological concentration. Furthermore, the recombinant 6G1 was shown to participate in the activation of prophenoloxidase cascade and to interfere with hyphal growth of the entomopathogenic fungus Paecilomyces tenuipes, injected into pupae of B. mori. These results suggest that 6G1 lipoprotein plays a role in the protection of B. mori against invading fungi.  相似文献   
119.
Clusterin has been implicated in lipid metabolism and atherogenesis, however, the influence of genetic variation has not been examined in Japanese. In this study, we identified 11 single nucleotide polymorphisms (SNPs) of clusterin gene by direct sequencing. Among them, one promoter SNP (-4453T>G), one missense SNP (4183G>A), and 2 common SNPs (5608T>C and 6316delT) were genotyped in 525 asymptomatic hypertensives not treated with lipid lowering agents. -4453T>G, 4183G>A, and 5608T>C showed no correlation with the clinical characteristics, however, in the 6316delT, an insertion (I)/deletion (D) polymorphism, D/D subjects had significantly higher levels of total cholesterol and low-density lipoprotein (LDL)-cholesterol than I/I subjects in females but not in males. Female subjects with the D allele (D/D+I/D) had greater intima-media thickness of the carotid artery than I/I subjects. In a multiple logistic regression analysis, the D allele of 6316delT was detected as an independent predictor for the plaque prevalence. In conclusion, the clusterin gene polymorphism may contribute to the serum lipid levels and the progression of carotid atherosclerosis in hypertensive Japanese females.  相似文献   
120.
Identification of tumor necrosis factor alpha (TNF alpha) as the key agent in inflammatory disorders led to new therapies specifically targeting TNF alpha and avoiding many side effects of earlier anti-inflammatory drugs. However, because of the wide spectrum of systems affected by TNF alpha, drugs targeting TNF alpha have a potential risk of delaying wound healing, secondary infections, and cancer. Indeed, increased risks of tuberculosis and carcinogenesis have been reported as side effects after anti-TNF alpha therapy. TNF alpha regulates many processes (e.g. immune response, cell cycle, and apoptosis) through several signal transduction pathways that convey the TNF alpha signals to the nucleus. Hypothesizing that specific TNF alpha-dependent pathways control specific processes and that inhibition of a specific pathway may yield even more precisely targeted therapies, we used oligonucleotide microarrays and parthenolide, an NF-kappa B-specific inhibitor, to identify the NF-kappa B-dependent set of the TNF alpha-regulated genes in human epidermal keratinocytes. Expression of approximately 40% of all TNF alpha-regulated genes depends on NF-kappa B; 17% are regulated early (1-4 h post-treatment), and 23% are regulated late (24-48 h). Cytokines and apoptosis-related and cornification proteins belong to the "early" NF-kappa B-dependent group, and antigen presentation proteins belong to the "late" group, whereas most cell cycle, RNA-processing, and metabolic enzymes are not NF-kappa B-dependent. Therefore, inflammation, immunomodulation, apoptosis, and differentiation are on the NF-kappa B pathway, and cell cycle, metabolism, and RNA processing are not. Most early genes contain consensus NF-kappaB binding sites in their promoter DNA and are, presumably, directly regulated by NF-kappa B, except, curiously, the cornification markers. Using siRNA silencing, we identified cFLIP/CFLAR as an essential NF-kappa B-dependent antiapoptotic gene. The results confirm our hypothesis, suggesting that inhibiting a specific TNF alpha-dependent signaling pathway may inhibit a specific TNF alpha-regulated process, leaving others unaffected. This could lead to more specific anti-inflammatory agents that are both more effective and safer.  相似文献   
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