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41.
42.
An improved system is described to recover non-transmissible Sendai virus that lack the envelope fusion (F) gene from cloned cDNA. The system (1) used plasmids that expressed the F and the HN viral envelope proteins, as well as the plasmids that expressed the viral NP, P, and L proteins as helper plasmids for recovery, and (2) overlaid packaging cells that expressed the F protein. With this improved system, we have succeeded in recovery of F-defective Sendai virus expressing two foreign proteins, and expression vectors that do not contain the EGFP reporter gene. This system may provide the basis for constructing recombinant F-defective Sendai virus for preventing and treating human diseases in the form of vaccines and vectors for gene therapy.  相似文献   
43.
OBJECTIVES: We investigated the relationship between P16-immunostaining patterns and clinicopathological factors in early uterine cervix cancers and assessed whether P16-immunostaining patterns predict the prognosis of the patients with early uterine cervix cancers. METHODS: Twenty-nine early squamous cell carcinoma (SCC) specimens of the uterus were examined using immunohistochemistry for P16 expression. The P16-immunostaining pattern was classified into two groups: the homogeneous type and the heterogeneous type. P16-immunostaining patterns were evaluated in different parts of the carcinoma in situ (CIS): the center of the tumor and the front interface of the infiltrating tumor. RESULTS: All specimens were of the homogeneous type in CIS. The P16-immunostaining pattern was significantly of the heterogeneous type in the front interface of the infiltrating tumor with lymphatic invasion, vascular invasion, lymph node metastasis, and recurrence. Regarding the P16-immunostaining patterns in the front interface of the infiltrating tumor, the patients with the heterogeneous type showed a significantly worse prognosis than the patients with the homogeneous type. CONCLUSIONS: The prognosis of patients with early uterine cervical SCC may be predicted by evaluating the P16-immunostaining pattern in the front interface of the infiltrating tumor.  相似文献   
44.
A "floral" variant of nodal marginal zone lymphoma   总被引:1,自引:0,他引:1  
We describe 6 cases of a specific variant of nodal marginal zone lymphoma with "floral" lymph follicles in patients ranging in age from 18 to 66 years. All 6 patients had lymphadenopathy, either local (n = 5) or systemic (n = 1), and good performance status (0), and none had fever, weight loss, or night sweating. They all underwent excisional biopsy. Histologically, all lesions had a distinctive morphology, with proliferation of medium-sized atypical lymphoid cells in the marginal zone, hyperplastic lymph follicles with enlarged germinal centers, and a thickened mantle zone. In places, folliculolysis was observed. On immunohistochemical staining, the atypical lymphoid cells showed a B-cell phenotype (CD20 +), IgM positivity in 2 of 5 cases, and negativity for CD5, CD10, CD23, CD43, bcl-6, and IgD. Polymerase chain reaction examination for immunoglobulin heavy chain in 5 cases showed monoclonality in all. Five patients did not receive adjuvant chemotherapy and had no recurrences. The patient with systemic lymphadenopathy received chemotherapy and had a complete response without relapse. This variant should be differentiated from the usual nodal marginal zone lymphoma because of its specific clinical and pathological features.  相似文献   
45.
Immediate hemolytic transfusion reactions (IHTR) occurred in the course of delayed hemolytic transfusion reactions (DHTR). An 84-year-old man had received a blood transfusion 20 years ago. Progressive anemia developed, because of continuous bleeding from a bladder tumor. He was transfused with concentrated red blood cells (CRC) which were Rh-E antigen negative, because he had anti-E antibodies (day 0). He received CRC on day 3, and underwent resection of bladder tumor on day 6. Although crossmatch-compatible CRCs were prepared for the operation, those were not required and were kept in a refrigerator in the ward. On day 9, when a CRC kept in the ward was transfused, he suddenly had a IHTR. In order to analyze a mechanism of IHTR, the anti-Jk(b) and anti-Di(b) antibodies, anti-HLA antibodies and the concentrations of inflammatory cytokines were measured in serum samples. The anti-Jk(b) and anti-Di(b) antibodies increased prior to IHTR experienced on day 9. The concentrations of IL-6 and IL-1beta increased from day 2, while the concentration of IL-8 increased from day 7. The anti-HLA class I antibody could be detected 2 days before IHTR. Thus, the anti-Jk(b) and anti-Di(b) antibodies induced the production of inflammatory cytokines and symptoms of DHTR and IHTR. The anti-HLA class I antibody could be produced in spite of using the filer for removing leukocytes, and may take part in the induction of IHTR. Further, blood products should be transfused soon after completing a crossmatch test in patients with anti-RBC alloantibodies.  相似文献   
46.
Copolymerization of N-carboxy-γ-benzyl-L -glutamate anhydride and ethylene oxide or DL-propylene oxide was carried out in the presence of triethylaluminum or diethylzine as catalyst with (or without) dioxane as solvent. From the data obtained by nuclear magnetic resonance spectroscopy, optical rotatory dispersion measurements, infrared absorption spectroscopy and turbidimetry, it was concluded that the copolymer obtained by the triethylaluminum catalyst consisted of two parts, peptide-block part and random or alternate part, while diethylzinc catalyst resulted in the formation of a less random copolymer only. In dioxane, formation of peptide-block part by triethylaluminum was suppressed to some extent.  相似文献   
47.
Summary Biological and biochemical characters of seven enterovirus 71 (E71) isolates were compared. Four isolates (two from patients with hand, foot and mouth disease [HFMD] and two from patients with encephalitis) grew in cynomolgus monkey kidney cells both at 39.5 and 35° C. However, the remaining three strains (from patients with HFMD) grew at 35° C, but not at 39.5° C. Three temperature-resistant and two temperature-sensitive strains were tested for neurovirulence in monkeys. Temperature-resistant strains were shown to be neurovirulent, whereas temperature-sensitive strains were less neurovirulent. The results suggest correlation between temperature-sensitive growth and neurovirulence in monkeys of E71. Variation in the electrophoretic mobility of the viral polypeptides was detected in three out of seven strains. The fingerprinting of oligonucleotides generated from the viral genome showed similar patterns in two isolates from patients with HFMD and one from patient with encephalitis and variable patterns in each genomic map of remaining four strains. These variations of polypeptide patterns and of oligonucleotide maps could not be correlated with pathogenicity (encephalitis or HFMD), temperature-sensitive growth and neurovirulence in monkeys.With 4 Figures  相似文献   
48.
BACKGROUND: Many genes are meiosis and/or sporulation-specifically transcribed during this process. Isolation and analysis of these genes might help us to understand how meiosis and sporulation are regulated. For this purpose, we have isolated a large number of cDNA clones from Schizosaccharomyces pombe whose expression is up-regulated during meiosis. RESULTS: We have isolated meu10+ gene, which encodes 416 amino acids and bears homology to SPS2 of Saccharomyces cerevisiae. A strain whose meu10+ gene has been deleted forms no viable spores. Thin-section electron micrographs showed that the meu10Delta strain has abnormally formed spore walls, and then they disrupt, allowing cytoplasmic material to escape. The Meu10-GFP fusion protein is localized to the spore periphery, thereafter returned to the cytoplasm after sporulation. Meu10-GFP localization to the spore wall was almost normal in the bgs2Delta or chs1Delta mutants that lack 1,3-beta-glucan or chitin, respectively. In contrast, 1,3-beta-glucan is abnormally localized in meu10Delta cells. Meu10 has an N-terminal domain with homology to the mammalian insulin receptor and a C-terminal domain with a transmembrane motif. Mutants whose N-terminal or C-terminal domain was truncated were severely defective for sporulation. CONCLUSIONS: Meu10 is a spore wall component and plays a pivotal role in the formation of the mature spore wall structure.  相似文献   
49.
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls  相似文献   
50.
It was found that methacholine and carbamylcholine, in addition to their known inhibitory effect, augmented the effect of isoproterenol on tissue cyclic AMP accumulation. The effect of methacholine was dose dependent, and significant augmentation was obtained at 0.1 microM with the maximum being attained at about 0.5 microM, whereas more than 10 microM were required to obtain the inhibitory effect. Atropine completely blocked the effect of methacholine. Similar augmentation of isoproterenol effect was obtained by oxotremorine and pilocarpine. Oxotremorine, however, did not inhibit the effect of isoproterenol. Difference in the effect between methacholine or carbamylcholine and oxotremorine was observed in their binding property to cholinergic receptors. A23187 augmented the effect of isoproterenol in a dose-dependent manner. Oxotremorine and A23187 augmented the effect of isoproterenol in the presence of isobutylmethylxanthine, but they did not augment the effect of forskolin and isobutylmethylxanthine on tissue cyclic AMP accumulation. Cholinergic agonist- and A23187-induced augmentation was abolished by omission of calcium in the medium. These results suggest that the augmentation is due to activation of adenylate cyclase, which is mediated by an increase in concentration of intracellular calcium.  相似文献   
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