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151.
We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/ fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p<0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.Abbreviations RLN regional lymph node(s) - OK-432/fbg OK-432/fibrinogen solution - PHA phytohemagglutinin - NK natural killer - LAK lymphocyte activated killer  相似文献   
152.
153.
Summary An integrated system has been constructed to instantly identify and efficiently sort the heterokaryons formed by plant protoplast fusion. The system is composed of the following functions: a) a transport system, b) an electro-manipulator, c) a cell harvester, d) a flow cytometer/cell sorter, and e) a control device. The conditions for an efficient and reproducible enrichment of the heterokaryons have been investigated by this system using the fluorescein isothiocyanate stained protoplasts preparing from Glycyrrhiza glabra cell cultures and unstained protoplasts of Abrus precatorius cell cultures which contain a large quantity of chlorophyll.Abbreviations MS Murashige and Skoog (1962) - 2,4-D 2, 4-dichlorophenoxyacetic acid - NAA 1-naphthaleneacetic acid - BAP 6-benzylaminopurine - ABA abscissic acid - FITC fluorescein isothiocyanate This paper is part 96 in the series Studies on Plant Tissue Cultures. For part 95 see Orinara Y., Noguchi T. and Furuya T. (1993) submitted for publication.  相似文献   
154.
We have shown that heat shock does not induce the synthesis of hsp70 in FM3A cells maintained at a low culture temperature of 33 degrees C although it does so in cells maintained at 37 degrees C [T. Hatayama et al. (1991) Biochem. Int. 24, 467-474]. In this paper, we show that FM3A cells maintained at 37 degrees C produced hsp70 mRNA during continuous heating at 42 degrees C or during postincubation at either 37 or 33 degrees C after being heated at 45 degrees C for 15 min, whereas cells maintained at 33 degrees C did not produce hsp70 mRNA during continuous heating at 37, 39, 42, or 45 degrees C, or during postincubation after being heated at any temperature. Thus the lack of hsp70 synthesis in cells maintained at 33 degrees C seemed to be due to the absence of hsp70 mRNA induction. Also, hsp70 was accumulated in cells maintained at 37 degrees C during continuous heating at 42 degrees C and during postincubation at 37 degrees C after heat shock at 45 degrees C, but not during postincubation at 33 degrees C. The cellular level of the constitutive hsp73 as well as the mRNA level were both similar in cells maintained at 33 and 37 degrees C. On the other hand, the cellular level of the constitutive hsp105 in cells maintained at 33 degrees C was only half of that in cells maintained at 37 degrees C. These hsp105 levels increased significantly in both types of cells after continuous heating at 39 degrees C. These findings indicate that the culture temperature affects not only the induction of hsp70 mRNA but also the accumulation of hsp70 and hsp105 in the cells.  相似文献   
155.
Rice (Oryza sativa L. cv. Yamabiko) seedlings germinated underwater for 5 days contained small amounts of heme a and protohemebut no protochlorophyll(ide) [Pchl(ide)]. Levels of hemes andPchl(ide) increased rapidly upon transfer to air. When expressedin terms of fresh weight of tissue, hemes reached the levelsin aerobic controls after 24 h of contact with air, but Pchl(ide)did not. A comparison of the increases during 24-h adaptationto air in levels of heme a and Pchl(ide), which are specificto mitochondria and plastids, respectively, suggested that thedevelopment of mitochondria preceded that of plastids. The rateof synthesis of 5-aminolevulinic acid (ALA) was low in submergedseedlings, as compared to the rate in aerobic controls, butit increased during air adaptation. The sum of the amounts ofheme a, protoheme and Pchl(ide) increased in parallel with theamount of porphyrins, equivalent to the amount of ALA synthesizedduring the experimental period. When submerged seedlings thathad been pretreated with levulinic acid were exposed to air,no Pchl(ide) was formed. In contrast, Pchl(ide) accumulatedunder water when submerged seedlings were fed with ALA. Theseresults indicate that the synthesis of ALA, the limiting stepin the synthesis of Pchl(ide), is repressed under hypoxic conditions. 1 Present address: KRI International, Inc., Kyoto Research Park17, Chudoji Minami-machi, Shimogyo-ku, Kyoto, 600 Japan. 2 Present address: Research Institute for Bioresources, OkayamaUniversity, Kurashiki, 710 Japan.  相似文献   
156.
A 562 base pair fragment of DNA from a serotype A strain of Vibrio anguillarum was cloned into pUC9 and used as a hybridization probe for the rapid identification of Vibrio anguillarum by colony hybridization. The probe was tested on nine different fish pathogens, 15 Vibrio isolates, 2 organisms closely related to Vibrio, and 9 serotypes of V. anguillarum. The probe hybridized only with the DNA of V. anguillarum serotypes A and H. The sequence of the 562 nucleotides have been determined. This probe allows rapid, reliable, and specific detection of V. anguillarum in freshwater ayu, Plecoglossus altivelis.  相似文献   
157.
158.
Chlorophyll (Chl) a', the C132-epimer of Chl a, is a constituent of the primary electron donor (P700) of Photosystem (PS) I of a thermophilic cyanobacterium Synechococcus (Thermosynechococcus) elongatus, as was recently demonstrated by X-ray crystallography. To determine whether PS I of oxygenic photosynthetic organisms universally contains one molecule of Chl a', pigment compositions of thylakoid membranes and PS I complexes isolated from the cyanobacteria T. elongatus and Synechocystis sp. PCC 6803, the green alga Chlamydomonas reinhardtii, and the green plant spinach, were examined by simultaneous detection of phylloquinone (the secondary electron acceptor of PS I) and Chl a' by reversed-phase HPLC. The results were compared with the Chl a/P700 ratio determined spectrophotometrically. The Chl a'/PS I ratios of thylakoid membranes and PS I were about 1 for all the organisms examined, and one Chl a' molecule was found in PS I even after most of the peripheral subunits were removed. Chl a' showed a characteristic extraction behaviour significantly different from the bulk Chl a in acetone/methanol extraction upon varying the mixing ratio. These findings confirm that a single Chl a' molecule in P700 is the universal feature of PS I of the Chl a-based oxygenic photosynthetic organisms.  相似文献   
159.
A simple and rapid quantitative method for 13C-labelled urea ([13C]urea) in human serum was developed by using high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (HPLC-APCI-MS). This method is used to establish and normalize the [13C]urea breath test, which is considered as an effective diagnostic method for Helicobacter pylori infection. HPLC-APCI-MS, involving a simple pretreatment process such as diluting serum with water, was shown to be able to discriminate the extrinsic [13C]urea from intrinsic urea present at high concentration in serum. In addition, a 13C nuclear magnetic resonance spectroscopic quantitative method for [13C]urea in human urine is also described. The precision and accuracy of measured concentrations in these two methods were found to be within the acceptable limit. An application of these methods to investigate the pharmacokinetic profile of orally administered [13C]urea in human serum and urine is also presented.  相似文献   
160.
To develop a dominant genetic marker inPleurotus ostreatus, mutant strains resistant to a carboxin-derived fungicide, flutolanil, were isolated. These mutants included strains which showed resistance to 50-fold higher concentration of fluotolanil than the wild-type strain, even after successive cultivations in the absence of the drug. Dominance of the phenotype was confirmed by back-crossing between the resistant and wild-type monokaryons. The flutolanilresistance was also shown to be stably inherited by the basidiospore-derived progenies of the mutant strains.  相似文献   
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