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81.
We previously found that the ability of peripheral blood mononuclear cells (PBM) of cancer patients to generate lymphokine-activated killer (LAK) cells became remarkably augmented after mitomycin C administration. On the basis of the clinical finding, we designed a treatment regimen comprised of 12 mg/m2 mitomycin C i. v. on day 1 and 700 U/m2 recombinant interleukin-2 (IL-2) i.v. every 12 h from day 4 through day 8. Of 25 patients with advanced carcinoma, 9 had a partial response and 3 had a minor response. Cytotoxic cell function, including natural killer activity, lymphokine-activated killer (LAK) activity, and the ability to generate LAK cells, and lymphocyte subsets in PBM was measured 1 day before and after either the first or second course of this therapy. The relationship between these parameters and the clinical antitumor response to this treatment was examined. Although the cytotoxic activities were significantly augmented after either the first or second treatment course, no positive correlation was observed between the changes in these cytotoxic activities and the clinical response to this therapy, when patients who either showed a partial response or whose disease remission was partial or minor were defined as responders. Further, phenotypic analysis showed a significant increase in CD2+, CD3+ CD4+ and CD4+Leu8 cells after the firs course, and CD25+ cells after either the first or second course of this treatment. The precentages of CD2+ and CD25+ cells were significantly elevated only in responders but not in nonresponders, suggesting the increase in these subsets was related to clinical response.  相似文献   
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Adeno-associated virus (AAV)-based gene therapy holds promise as a fundamental treatment for genetic disorders. For clinical applications, it is necessary to control AAV release timing to avoid an immune response to AAV. Here we propose an ultrasound (US)-triggered on-demand AAV release system using alginate hydrogel microbeads (AHMs) with a release enhancer. By using a centrifuge-based microdroplet shooting device, the AHMs encapsulating AAV with tungsten microparticles (W-MPs) are fabricated. Since W-MPs work as release enhancers, the AHMs have high sensitivity to the US with localized variation in acoustic impedance for improving the release of AAV. Furthermore, AHMs were coated with poly-l -lysine (PLL) to adjust the release of AAV. By applying US to the AAV encapsulating AHMs with W-MPs, the AAV was released on demand, and gene transfection to cells by AAV was confirmed without loss of AAV activity. This proposed US-triggered AAV release system expands methodological possibilities in gene therapy.  相似文献   
84.
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East...  相似文献   
85.
This paper reports an electron microscope study of typical and atypical spermatogenesis in the pond snail, Cipangopaludina malteata. In the typical spermatid the nucleus undergoes profound changes as development proceeds, affecting both its form and internal fine structure. A large number of roughly parallel, dense filaments, arranged along the long axis of the nucleus, fuse with each other to form in the end the homogeneous helical body characteristic of the head of the adult spermatozoa. The nebenkern is apparently mitochondrial in nature and, in its early development, is similar to that of insects except that it appears as a double structure from the beginning. As differentiation proceeds, the mitochondria lose their membranes, and the residual, now denuded cristae, reorganize to give a parallel radial arrangement. In the last stages of development, the nebenkern derivations become applied to the sheath of the middle piece in a compact helical fashion. In the development of the atypical spermatozoa, the nucleus fails to differentiate and simply shrinks in volume until only a remnant, devoid of DNA, is left. The cytoplasm shows numerous vesicles containing small Feulgen-positive bodies, 80 to 130 mµ in diameter. These vesicles plus contents increase in number as spermatogenesis proceeds. The "head" structure of the atypical spermatozoa consists of a bundle (7 to 17) of tail flagella, each with a centriole at its anterior end. The end-piece of the atypical form appears brush-like and is made up of the free ends of the several flagella.  相似文献   
86.
Catalases purified from endosperm glyoxysomes and non-specializedmicrobodies from hypocotyls of castor bean seedlings differedin their specific activity [90–164 and 0.89–4.9kunits (mg protein)–1, respectively] and in their constituentsubunits [two subunits of 54 and 56 kDa for the endosperm enzymeand only one of 56 kDa for the hypocotyl enzyme]. Immunoblotanalysis also showed that particulate fractions from the endospermsand from etiolated and green cotyledons contained two catalasesubunits of 54 and 56 kDa, whereas such fractions from the hypocotylsand roots contained only the 56-kDa subunit. Leaf peroxisomesfrom green leaves had two catalase subunits of around 55 kDaeach. Results of translation in vitro indicated that the 54-and 56-kDa subunits were translated from distinct mRNAs andlevels of both mRNAs increased in the endosperms during germination,prior to increases in levels of catalase proteins. In the hypocotyls,the 56-kDa subunit seemed to be synthesized constitutively. 1Present addresses: YO, Toyota Central Institute, 31-9 Musashizuka,Nagabuchi, Nagakute, Aichi 480-11, Japan  相似文献   
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Approximately 2,000 embryogenic uninuclear microspores of rapeseed (Brassica napus) cv. Topas were intranuclearly injected with a chimaeric -glucuronidase (Escherichia coli Uid A) gene. Stable integration had not occurred among 55 plants that were regenerated. Coinjection of the dye Lucifer Yellow and detection of injected DNA by the polymerase chain reaction revealed high frequencies of transfer. However, the amount of DNA injected was less than 20 copies, which may have been insufficient for stable transformation of microspores.Abbreviations PCR polymerase chain reaction - GUS -glucuronidase  相似文献   
90.
The Cd(II) complex of a peptide, Z-Cys-Ala-Pro-His-OMe was prepared and characterized by absorption, CD, 1H-, 13C-, and 113Cd-nmr, and nuclear Overhauser effect spectroscopy (NOESY) spectra to show the coordination of cysteine thiolate and histidine imizazole to Cd(II) ion. The NOESY spectra in dimethyl formamide showed that the cysteine residue was in proximity to the histidine residue. These results reveal the dictation of Z-Cys-Ala-Pro-His-OMe to Cd(II) ion in solution. Temperature-dependent dissociation equilibrium of histidine imidazole in solution was observed in this complex. Structural features of the chelating peptide are discussed. © 1995 John Wiley & Sons, Inc.  相似文献   
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