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171.
172.
Interest in the production of lactic acid (LA) is increasing inrelation to its applications in the synthesis of biodegradablepolymer materials. Before kitchen waste is used as substrates inLA fermentation, it must be stored for some days in the wastecollection system. This study examined the effects of pHadjustment including initial pH before the storage in terms of thekind and the amount of added acid on preservation of the waste. The optical purity of LA generated during the storage was alsoanalyzed. It was found that antibacterial activity andsuppression ability to D-lactic acid (D-LA) were stronger in theorder: acetic acid > L-lactic acid (L-LA) > hydrochloric acid ≈ nitric acid. The optimum condition of waste storage was found to be adjusting initial pH to 3.4 by adding acetic acid. It can be expected that preservation of kitchen waste can be realized by inhibiting the growth of putrefactive bacteria, and higher optical purity of L-LA was obtained by adding weak acid to the waste.  相似文献   
173.
Lignin extracted with acidic dioxane was investigated as a possible standard for quantitatively determining lignin content in plant samples using the spectrophotometric method employing acetyl bromide. Acidic dioxane lignins were analyzed for carbohydrate, total protein, nitrobenzene oxidation products, and UV spectral characteristics. Total carbohydrate content of isolated lignins ranged from 2.21 to 5.70%, while protein ranged from 0.95 to 6.06% depending upon the plant source of the original cell wall sample. Nitrobenzene analysis indicated differences in the amount of guaiacyl and syringyl units making up the lignins, but this did not alter the UV spectrum of lignin solubilized in acetyl bromide. Regression equations developed for the acetyl bromide method using the isolated lignins for all the plant samples were similar to each other. Lignin values obtained by the acetyl bromide method were similar to the lignin values obtained as acid insoluble residues following a Klason lignin procedure.  相似文献   
174.
The residual amount of nonionized pesticides incorporated to foliage and stem (foliage) and seed (fruit) of crops via root hairs from the water phase was estimated using the uptake models newly including metabolic parameters by which the amount of intact pesticide remaining in crops was considered with its proportion in a transpiration stream. A new parameter was also introduced for the seed model that accounts for the pesticide loss by adsorption to the inner surface of xylem tissue. Validation of the model was conducted using six pesticides with soybean and spinach plants. The ratio of the predicted concentration of pesticide to the measured one was 0.44-1.49 and 0.57-2.93 with foliage and seed models, respectively, showing that these improved models would be effective as a prediction tool.  相似文献   
175.
After a cell wall protein fraction (CWP) of Pythium oligandrum was sprayed on sugar beet leaves, we screened leaves for induced expression of defence-related genes and for resistance against Cercospora leaf spot. In a western blot analysis, the CWP was primarily retained on the surface of leaves without degradation for at least 48 h after spraying. In northern blot analyses, four defence-related genes (β-1, 3-glucanase, acidic class III chitinase, 5-enol-pyruvylshikimate-phosphate synthase and oxalate oxidase-like germin) were expressed more rapidly in CWP-treated leaves compared to control leaves treated with distilled water (DW). When CWP was applied to a suspension of cultured cells of sugar beet, an oxidative burst was observed that did not occur after the DW treatment. In growth chamber trials after inoculation with Cercospora beticola, the severity of Cercospora leaf spot was significantly reduced in CWP-treated plants compared to the DW-treated controls. In a field experiment, CWP treatment was also effective against the disease. CWP did not reduce growth rate of the pathogen in plate tests. The results together suggest that the CWP from P. oligandrum can be retained on the leaf surface and induce expression of disease resistance genes, thereby reducing Cercospora leaf spot on sugar beet.  相似文献   
176.
We investigated whether CIDR-based ovulation-synchronization protocols inhibit secretion of prostaglandin (PG) F2alpha from the uterus in the following luteal phase in non-cycling beef cows. Ten early (a month) postpartum non-cycling Japanese Black beef cows were treated with (1) Ovsynch (GnRH analogue on Day 0, PGF2alpha analogue on Day 7, and GnRH analogue on Day 9; n=3), (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from Day 0; n=4), or (3) estradiol benzoate (EB) Ovsynch+CIDR (EB on Day 0 in lieu of the first GnRH treatment followed by the Ovsynch+CIDR protocol; n=3). An oxytocin challenge was administered on Day 24 to examine uterine PGF2alpha secretion. Plasma concentrations of 13,14-dihydro-15-keto- PGF2alpha were lower at 30-120 min after oxytocin administration in the Ovsynch+CIDR group and 75 min after administration in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). Plasma progesterone concentrations were higher from Days 1 to 7 in the Ovsynch+CIDR group and from Days 1 to 5 in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). The progesterone concentrations were higher on Days 27 and 29 in both CIDR-treated groups than in the Ovsynch group (P<0.05). In conclusion, in non-cycling beef cows, CIDR-based ovulation-synchronization protocols inhibit uterine PGF2alpha secretion in the following luteal phase and prevent premature luteolysis as is seen with the Ovsynch protocol.  相似文献   
177.
A novel thrombin inhibitory protein coding gene was identified from a cDNA library derived from salivary gland of partially-fed Haemaphysalis longicornis (hard tick). The gene encoded a 93-amino acid protein, designated chimadanin, which had a signal peptide sequence and was predicted to be a secretory protein. It showed no similarity to any other previously identified proteins or conserved domain sequences. The gene was expressed during blood feeding and suggested to be expressed mainly in the salivary gland. The predicted mature region of chimadanin was expressed in Escherichia coli and characteristics of the recombinant chimadanin were determined. The activated partial thromboplastin time and the prothrombin time in sheep plasma were significantly prolonged by chimadanin in a dose dependent manner. Amidolytic activity of thrombin was also inhibited by chimadanin in a dose dependent manner and it suggested that chimadanin was an anticoagulant with thrombin inhibitory activity. This newly identified thrombin inhibitor may play an important role in tick blood feeding.  相似文献   
178.
Molecular cloning of feline lung resistance-related protein (LRP) was performed to evaluate the relationship between its expression level and drug resistance against chemotherapeutics. The nucleotide sequence of the coding region of feline LRP cDNA was found to be 2670-bp long and to show 84.2-92.6% homology to its human, mouse, and rat counterparts. The expression level of feline LRP mRNA was relatively high in lung, jejunum, and colon. An adriamycin (ADM)-resistant feline lymphoma subline, FT-1/ADM, showed a high level of MDR1 mRNA expression compared with parental FT-1 cells. However, no relationship was observed between the drug-resistant phenotype and the LRP mRNA expression level. Although no direct contribution of LRP to the development of the drug-resistant phenotype was observed, further investigation is advisable.  相似文献   
179.
180.
To evaluate pulmonary toxicity of multi-walled carbon nanotubes (MWCNTs), F344 rats of both sexes were exposed by inhalation to 0.2, 1 or 5 mg/m3 MWCNT aerosol for 6 h/day, 5 days/week for 2 weeks using a whole-body exposure system. At the end of the 2-week exposure period, one-half of the rats were necropsied, and at the end of an additional 4-week postexposure period, the remaining rats were necropsied. MWCNTs were deposited in the lungs of all MWCNT-exposed groups and mostly remained in the lungs throughout the 4-week postexposure period. Granulomatous changes in the lung were found in the rats exposed to 5 mg/m3 MWCNTs, and these changes were slightly aggravated at the end of the 4-week postexposure period. In the bronchoalveolar lavage fluid (BALF), the numbers of neutrophils, percentages of bi- and multinucleated alveolar macrophages, levels of ALP activity and concentrations of total protein and albumin were elevated in the rats exposed to 1 and 5 mg/m3 MWCNTs. At the end of the 4-week postexposure period, the values of the BALF parameters tended to remain elevated. In addition, goblet cell hyperplasias in the nasal cavity and nasopharynx were observed in the rats exposed to 1 and 5 mg/m3 MWCNTs, but these lesions had largely regressed by the end of the postexposure period. Based on the histopathological and inflammatory changes, the no-observed-adverse-effect level (NOAEL) for inhalation of MWCNTs for 2 weeks was 0.2 mg/m3.  相似文献   
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