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941.
942.
A reinjection experiment has been conducted in an attempt to sustain reservoir pressure and steam production and to extract remaining heat energy in the superheated reservoir in the Matsukawa vapor-dominated geothermal field. This experiment was undertaken because the increase in superheat of produced steam and the decline of steam production are the current major issues for stable operation of the power plant. Almost all the reinjected fluid into well MR 1 was recovered from well M5, and the steam production of well M5 has increased by approximately 67%. 相似文献
943.
Safety assessment of paper and board food packaging: Chemical analysis and genotoxicity of possible contaminants in packaging 总被引:4,自引:0,他引:4
Asako Ozaki Yukihiko Yamaguchi Tadao Fujita Koichi Kuroda Ginji Endo 《Food Additives & Contaminants》2005,22(10):1053-1060
In order to identify potential genotoxicant(s) in recycled paperboard, samples were fractionated using multiple liquid/liquid extraction, and gel permeation chromatography, and analysed by gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. The rec-assay was used as an indicator of genotoxicity. Genotoxicants in the recycled paperboard were identified as dehydroabietic acid (DHA) and abietic acid (AA). DHA and AA were detected in two out of five virgin products, and in all seven recycled products for food-contact use. Total amounts of DHA and AA were 240 and 990 µg/g in the virgin products and 200-990 µg/g in the recycled products. A good correlation was observed in the total amount of DHA and AA content determined in paper products and DNA-damaging activity. Moreover, genotoxic effects in paper products showed a good match with standard compounds, indicating that the genotoxic effects of these paper products was mostly attributable to DHA and AA. 相似文献
944.
We used culture- and molecular-biology-based methods to investigate the diversity of lactic acid bacteria (LAB) in the ethnic chevon (goat) meat products chartayshya, jamma and arjia of the Western Himalayas. In six chartayshya, six jamma and four arjia samples, LAB were the predominant microbial component involved in the fermentation of these samples, and the total LAB population in arjia (7.8 ± 0.1 log cfu g−1; mean ± SD) was significantly higher (P < 0.05) than in chartayshya (6.9 ± 0.1 log cfu g−1) and jamma (7.5 ± 0.1 log cfu g−1). We identified 53 LAB samples by 16S rRNA and phenylalanyl-tRNA synthase (pheS) genes sequencing. The LAB isolates were identified as Enterococcus durans, Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Leuconostoc citreum, Leuconostoc mesenteroides, Pediococcus pentosaceus, and Weissella cibaria. These results revealed that there is a high level of diversity of LAB in the Himalayan ethnic preserved meat products. 相似文献
945.
Nakazawa N Okawa K Sato T Enei H Harashima S 《Journal of Bioscience and Bioengineering》1999,88(5):468-471
We have developed a mass mating method using the spore suspensions of homothallic yeasts of Saccharomyces cerevisiae in combination with dominant selective drug resistance markers, Tn601(903) against geneticin and AUR1-C against aureobasidin A for the selection of the hybrids. To examine the effectiveness of these markers in the mass mating method, each marker was introduced into a homothallic wine yeast. Using a mixed culture of spore suspensions from the resultant transformants, many hybrids were screened by the drug resistance markers. This method is more practical than the spore-to-spore mating method because it does not require the use of a micromanipulator and many hybrids are obtained at one time. The resultant hybrids could be utilized for industrial brewing because plasmids, which are used to confer resistance markers, are easily eliminated from the hybrids by cultivation in a medium without drugs. We propose that the mass mating method using spore suspensions in combination with dominant selective geneticin- and aureobasidin A-resistance markers is useful for the selection of hybrids from industrial homothallic yeasts. 相似文献
946.
BACKGROUND AND PURPOSE: Little is known about bone changes in hemiplegic stroke patients. We evaluated the vitamin D status and bone changes on the hemiplegic and intact sides of stroke patients. METHODS: Sera were collected from 87 hemiplegic stroke patients (42 outpatients and 45 inpatients) and from 28 control subjects. The sera were assayed for 25-hydroxyvitamin D (25-OHD). Bone density was measured bilaterally from radiographs of the hands. Diet and sunlight exposure were assessed for all subjects. RESULTS: Serum 25-OHD concentrations were lower in patients (9.1 +/- 4.9 ng/mL for outpatients, 5.9 +/- 4.1 ng/mL for inpatients) than in control subjects (21.6 +/- 3.1 ng/mL). The difference in serum 25-OHD between the two patient groups also was statistically significant. The patients' microdensitometric scores for osteopenia were higher on the hemiplegic side than on the non-hemiplegic side. The microdensitometric scores and their side-to-side differences in patients correlated negatively with the serum 25-OHD concentration and positively with the degree of paralysis. Dietary intake of vitamin D was below the recommended level in 72% of the patients, and 89% of the patients were considered sunlight-deprived. CONCLUSIONS: Bone mass was reduced significantly on the hemiplegic side in the stroke patients, which might increase the risk of hip fracture. Vitamin D deficiency and disuse are the probable causes of osteopenia in this population. The hypovitaminosis D might be corrected readily by routine use of vitamin D supplements. 相似文献
947.
A vacuolar type H(+)-ATPase inhibitor, concanamycin A (CMA), raised the pH and induced morphologic changes such as vacuolation in lytic granules in the CD8+ cytotoxic T lymphocyte clone OE4. Here we measured the pH in lytic granules present in OE4 by immunoelectron microscopic observation using (3-(2,4-dinitroanilino)-3'-amino-N-methyldipropylamine (DAMP) as a pH probe. In control OE4, only the peripheral region, but not cores, were heavily stained with DAMP. Exposure to 100 nM CMA for 60 min raised the pH in the lytic granules from 5.7 +/- 0.2 to 6.8 +/- 0.2. Furthermore, the number of lytic granules in OE4 was estimated under phase contrast microscopy after Wright staining. About 20 lytic granules in average were detected in control cells, while CMA induced vacuolation and decreased their number by 20 to 30%. 相似文献
948.
T Chiba T Shitomi O Nakano H Shimotono H Yamada E Fujimaki S Orii K Sato S Sato 《Canadian Metallurgical Quarterly》1996,91(4):802-804
A 79-year-old woman was admitted to our hospital with complaints of dysphagia and multiple verrucous papules that had developed over the previous year. The diagnosis of esophageal carcinoma was based on upper gastrointestinal radiography and endoscopic examination with biopsy. The clinical syndrome was consistent with the sign of Leser-Trelat associated with esophageal carcinoma. Although radiation therapy and chemotherapy were undertaken, the patient died 8 months later because of the sign of Leser-Trelat in association with squamous cell esophageal carcinoma. 相似文献
949.
Y Sugawara T Konishi M Hiraishi A Sato H Natomi T Aoki M Makuuchi 《Canadian Metallurgical Quarterly》1996,43(10):995-999
A patient with primary gastric carcinoma showing a high level of serum a-fetoprotein (AFP) (368 ng/ml) is described. Subtotal gastrectomy was performed, and a month after surgery the level of serum AFP fell rapidly to within normal limits. Histologically, two types of cells coexisted in the tumor: medullary-type cells resembling trabecular-type hepatocellular carcinoma, and moderately differentiated adenocarcinoma cells. The cells of the former type were arranged mostly in a trabecular pattern with bile granules, but also showed a scirrhous pattern in a restricted area. Immunohistochemistry demonstrated that both types of tumor cells stained positively for AFP. This tumor, which should be classified as a hepatoid adenocarcinoma of the stomach, is of interest because of its rarity, bile secretion (indicating marked differentiation toward a hepatocyte form), and two cellular arrangements-trabecular and scirrhous. 相似文献
950.
H Akita Y Sato Y Kusumoto S Iwata Y Takeuchi T Aoyama T Yokota K Sunakawa 《Canadian Metallurgical Quarterly》1996,49(10):899-916
Azithromycin (AZM), a new macrolide antibiotic, in fine granules and in capsules was studied for pharmacokinetic and clinical evaluation in the pediatric patients. Antibacterial activity of AZM against 43 clinical isolates: AZM exhibited slightly lower activity against Gram-positive bacteria and 2-8-fold higher activity against Gram-negative bacteria than erythromycin or clarithromycin. Plasma or urine samples were collected from eight patients receiving the drug in fine granular form, and two patients receiving it in capsules for the determination of drug levels. The elimination half-lives of AZM after administration at dose of 10 mg/kg/day for 3 days were 50.0 and 51.2 hours for fine granules, and 41.5 hours for capsules. AUC0-infinity was 11.7 and 24.3 micrograms.hr/ml for fine granules, and 8.3 micrograms.hr/ml for capsules. The cumulative excretion rates up to 120 hours after the start of treatment were 8.24 and 13.84% for fine granules, and 3.83% for capsules. AZM was administered to 123 patients once daily at 3.7-20.0 mg/kg body weight over 3 to 5 days with reference to the standard dose of 10 mg/kg. The drug was used to treat patients with pharyngitis, tonsillitis, scarlet fever, pneumonia, mycoplasmal pneumonia, chlamydial pneumonia, otitis media, pertussis, intestinal infection, and SSTI. The effectiveness of AZM was evaluated in 109 cases. The drug was rated "excellent" in 65.1% of the patients and "good" in 29.4%, resulting in an efficacy rate of 94.5%. Furthermore, AZM eradicated 43 of 46 (93.5%) bacteria that had been identified before the treatment. Three patients complained of side effects of urticaria (1 case) and diarrhea (2 cases). Abnormal laboratory changes were reported as follows: decreased leukocyte (3 cases), increased eosinophil (5), increased platelet (2), increased eosinophil and platelet, elevated GPT (1), and elevated GOT and GPT (1). The abnormalities, however, were mild enough to raise no clinically significant problems. In conclusion, AZM in once daily regimen was effective and safe in treatment of pediatric infections. 相似文献