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11.
This study aimed to examine whether walking in water produces age-related differences in muscle activity, stride frequency (SF), and heart rate (HR) response. Surface electromyography (EMG) was used to evaluate muscle activities in six older and six young subjects while they walked in water immersed to the level of the xiphoid process. The trials in water utilized the Flowmill which consists of a treadmill at the base of a water flume. The measurement of maximal voluntary contraction (MVC) of each muscle was made prior to the gait analysis. The %MVCs, which refer to the surface EMG measures, from the gastrocnemius of the older subjects were significantly lower than those of the young subjects, in every experimental condition (P<0.05). In contrast, the %MVCs from the rectus femoris (P<0.05) and the biceps femoris (P<0.001) of older subjects were significantly greater than those of young subjects in every experimental condition. Moreover, the SFs of older subjects were also significantly greater than those of young subjects (P<0.05), while the HR responses of older and young subjects were similar. In conclusion, the older subjects had increased hip musculature activity and decreased ankle plantar flexor activity while walking in water, compared with the young subjects.  相似文献   
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Summary Streptomyces peucetius cells were immobilized by entrapment in calcium alginate and a photosensitive synthetic polymer, and used for the production of daunorubicin (daunomycin), which is known to be an antitumour reagent. The use of cultivation media removed insoluble components in a natural medium prevented rapid decrease in daunorubicin titer after maximum production. These entrapped cells could be used at least five times for repeated daunorubicin production; the total cultivation period was 45 days.  相似文献   
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Summary We investigated possible association of and linkage between HLA and familial polyposis coli (FPC). In 182 individuals from 66 pedigrees of FPC and 108 individuals from a normal population, HLA-A,-B, and-C antigens were determined. When the frequencies of HLA antigens in 66 unrelated patients and in normal controls were compared, no association of FPC with HLA was observed. For the linkage analysis, HLA haplotypes of 17 affected sib pairs were investigated by the affected sib pair method. The number of pairs which shared two, one, and no haplotypes identical by descent was not significantly different from the number expected with random occurrence (P>0.95). Finally, seven families were analyzed using Morton's sequential test. A maximum lod score of-0.056 at a recombination fraction of 0.4, and a lod of-3.089 at a recombination fraction of 0.05 were obtained. Therefore, there is neither an association of nor linkage between FPC and HLA.  相似文献   
15.
A genomic clone bank of Acetobacter polyoxogenes NBI1028 constructed in Escherichia coli by use of the expression vector pUC18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (ALDH; 75 kilodaltons [kDa]) from A. polyoxogenes NBI1028. A clone that synthesized a 41-kDa protein cross-reactive with anti-ALDH antibody was isolated. For cloning of the full-length ALDH structural gene, a cosmid gene bank was screened by Southern blot hybridization with the cloned DNA as a probe, and subcloning from the positive cosmid clone was performed with shuttle vector pMV24. Plasmid pAL25, containing the full-length ALDH structural gene, was isolated and expressed in both E. coli and Acetobacter aceti to produce a fused protein (78 kDa) with a short NH2-terminal β-galactosidase peptide. pAL25 conferred ALDH production on a mutant of A. aceti lacking the enzyme activity. Transformation of A. aceti subsp. xylinum NBI2099 with pAL25 caused 2- and 1.4-fold increases in the production rate and in the maximum concentration of acetic acid in submerged fermentation, respectively.  相似文献   
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The influence of centrifugal force on the growth of cells was examined by exposing the cells of the mouse-human hybridoma X87 line to centrifugal force (100–500 G) for ten minutes twice a day and comparing the static culture with that of unexposed cells. In this experiment, both cell proliferation and specific antibody productivity were independent of the centrifugal effect, and gave the same results as in the case of no exposure to centrifugal force. High density cultivation of the mouse-human hybridoma X87 line was obtained by a perfusion system where the cells were separated from the culture medium by continuous centrifugation. In the serum-free culture, the maximum viable cell density exceeded 107 cells/ml, and monoclonal antibody was stably produced for 37 days. The results in this culture were equivalent to those obtained by intermittent centrifugal cell separation from the culture medium, and separation by gravitational settlement.  相似文献   
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Summary The three-dimensional structure of endothelial cells in the hepatic sinusoids of the rat was studied by application of light- and electron microscopy on Golgi-impregnated specimens. A number of endothelial cells could thus be individually delineated throughout the hepatic lobules. The cytoplasm, showing heavy silver deposits, consists of two distinct areas, a thick and thin portion. The thick portion, issuing from the region of the perikaryon, branches and tapers toward the cell periphery. The thin portion, occupying the remainder of the cytoplasm, consists largely of highly fenestrated sieve plates. Some intralobular variation can be noted; the thick portion of the endothelial cells is well developed in the periportal zone, while the cells in the centrilobular zone are relatively rich in thin portions. In addition, the area of distribution of an individual endothelial cell is larger in the centrilobular sinusoids than in the periportal zone. Some endothelial cells also possess unique cytoplasmic processes projecting into the intercellular space between hepatocytes and connecting the sinusoidal walls of neighboring sinusoids. These processes may anchor the endothelial cells to the hepatic plates.  相似文献   
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Summary The oxygen-diffusivity (D m ) of 16 different gels formed with synthetic prepolymers (photo-crosslinkable resins, urethane resins and photosensitive resins), and that of calcium alginate (for comparison) was determined, using an oxygen electrode covered by the gel membranes with stepwise enzymatic removal of O2 from the buffer solution. The water content of the gels was found to be decisive for the O2-diffusivity of the gels: gels with the highest water content showed also the highest D m . From these findings, the suitability of different polymeric gels for substrate conversion and biosensor systems could be predicted.Abbreviations A surface area of the cathode - c O2-concentration in the membrane - d m total thickness of the membrane - D m O2-diffusivity in the membrane - ENT, ENTP polymers prepared from hydroxyethylacrylate - ENTA, ENTC isophorone diisocyanate and linear skeleton of different molecular weight of poly(ethylene glycol) (ENT) or poly(propylene glycol) (ENTP), resp. ENTA in addition bears anionic groups, ENTC cationic groups - F Faraday's constant - i s steady-state O2 reduction current - N number of electrons per mole unit of reaction - PU polyurethane polymers with poly(ethylene glycol) and poly(propylene glycol) parts in the diol moiety and isocyanate functional groups at both terminals of the prepolymer - PVA-SbQ polyvinyl alcohol stilbazolium polymer  相似文献   
20.
Summary The specific oxygen uptake rate of hybridoma cells immobilized in calcium alginate gel particles was measured, and the observed data was compared with those of non-immobilized cells. The uptake rate of the immobilized cells coincided with that of the non-immobilized hybridoma cells just after immobilization, but increased with cell growth. On the other hand, the cellular glucose consumption rate decreased slightly during the experiments. The increased oxygen uptake rate by immobilized cells was closely related to the formation of cell colonies in the gel particles.  相似文献   
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