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121.
Our previous study showed that relatively low-intensity (approximately 50% one-repetition maximum [1RM]) resistance training (knee extension) with slow movement and tonic force generation (LST) caused as significant an increase in muscular size and strength as high-intensity (approximately 80% 1RM) resistance training with normal speed (HN). However, that study examined only local effects of one type of exercise (knee extension) on knee extensor muscles. The present study was performed to examine whether a whole-body LST resistance training regimen is as effective on muscular hypertrophy and strength gain as HN resistance training. Thirty-six healthy young men without experience of regular resistance training were assigned into three groups (each n = 12) and performed whole-body resistance training regimens comprising five types of exercise (vertical squat, chest press, latissimus dorsi pull-down, abdominal bend, and back extension: three sets each) with LST (approximately 55-60% 1RM, 3 seconds for eccentric and concentric actions, and no relaxing phase); HN (approximately 80-90% 1RM, 1 second for concentric and eccentric actions, 1 second for relaxing); and a sedentary control group (CON). The mean repetition maximum was eight-repetition maximum in LST and HN. The training session was performed twice a week for 13 weeks. The LST training caused significant (p < 0.05) increases in whole-body muscle thickness (6.8 +/- 3.4% in a sum of six sites) and 1RM strength (33.0 +/- 8.8% in a sum of five exercises) comparable with those induced by HN training (9.1 +/- 4.2%, 41.2 +/- 7.6% in each measurement item). There were no such changes in the CON group. The results suggest that a whole-body LST resistance training regimen is as effective for muscular hypertrophy and strength gain as HN resistance training.  相似文献   
122.
A vertical flat-plate photobioreactor was developed for the outdoor culture of microalgae using sunlight as the light source. The ability for biomass production and CO2 fixation was evaluated by using a cyanobacterium, Synechocystis aquatilis SI-2. The average areal productivity was 31 g biomass m–2 d–1, which corresponded to a CO2 fixation rate of 51 g CO2 m–2 d–1, sustainable in the northern region of Japan during the winter time (January and February). The relationships between the efficiency of solar energy utilization of the reactor and its effect factors (cell concentration and irradiation) were investigated.  相似文献   
123.
The 13C NMR spectra of the pheophorbide of bacteriochlorophyll c, formed in the presence of L-[1-13C]glutamate and [2-13C]glycine and [13C]bicarbonate in Prosthecochloris aestaurii, were analysed. The isotope in the glutamate was specifically incorporated into the eight carbon atoms in the tetrapyrrole macrocycle derived from the C-5 of 5-aminolevulinic acid, while no specific enrichment of these eight carbon atoms was observed in the spectrum of the pigment formed in the presence of [2-13C]glycine. These labelling patterns provide evidence for the operation of the C5 pathway of 5-aminolevulinic acid synthesis for bacteriochlorophyll c formation in the bacterium. The labelling of bacteriochlorophyll c by [13C]bicarbonate is consistent with its formation from 5-[1,4,5-13C]aminolevulinic acid formed by the C5 pathway from [1,2,5-13C]glutamic acid. It is proposed that this glutamate is the transamination product of 2-[1,2,5-13C]oxoglutaric acid, arising by carboxylation of [1,4-13C]succinyl-CoA with 13CO2 catalysed by 2-oxoglutaric acid synthase activity, and that the labelled succinyl-CoA is, in turn, derived by the fixation of 13CO2 by the reductive tricarboxylic acid cycle. The 13C chemical shifts of two sp2 quaternary carbons of bacteriopheophorbide c methyl ester (C-2 and C-4) were reassigned.  相似文献   
124.
125.
We present a practical synthesis of both enantiomers of 1,2,3,4-tetrahydroisoquinoline derivative IPPAM-1 (1), which is a positive allosteric modulator (PAM) of prostacyclin receptor (IP) and a candidate for treatment of pulmonary arterial hypertension without the side effects caused by IP agonists. Assay of cAMP production by CHO-K1 cells stably expressing human IP clearly demonstrated that the IPPAM activity resides exclusively on the R-form of 1.  相似文献   
126.
Long-term supplementation with branched-chain amino acids (BCAA) is associated with prolonged survival and decreased frequency of development of hepatocellular carcinoma (HCC) in patients with liver cirrhosis. However, the pharmaceutical mechanism underlying this association is still unclear. We investigated whether continuous BCAA supplementation increases survival rate of rats exposed to a fibrogenic agent and influences the iron accumulation, oxidative stress, fibrosis, and gluconeogenesis in the liver. Further, the effects of BCAA on gluconeogenesis in cultured cells were also investigated. A significant improvement in cumulative survival was observed in BCAA-supplemented rats with advanced cirrhosis compared to untreated rats with cirrhosis (P<0.05). The prolonged survival due to BCAA supplementation was associated with reduction of iron contents, reactive oxygen species production and attenuated fibrosis in the liver. In addition, BCAA ameliorated glucose metabolism by forkhead box protein O1 pathway in the liver. BCAA prolongs survival in cirrhotic rats and this was likely the consequences of reduced iron accumulation, oxidative stress and fibrosis and improved glucose metabolism in the liver.  相似文献   
127.
A procedure was developed for isolating mesophyll cells frommulberry leaves that have consistently high photosynthetic activity.To obtain photosynthetically active cells from some plants,their petioles, immersed in water, had to be kept in the darkfor 3–4 days prior to cell isolation. (Received May 6, 1983; Accepted August 15, 1983)  相似文献   
128.
During photosynthetic 14CO2-fixation, leaves of plants suchas wheat, the broad bean and spinach, which had been acclimatizedto high temperature (20–25?C), incorporated much moreradioactivity into sucrose, and less into glycine and serinein comparison with similar plants grown in the cold (mean temperature,5–7?C). Radioactivities incorporated into glycine and serine greatlydescreased on the addition of -hydroxyethylsulfonate or on theremoval of oxygen from the atmosphere, indicating that thesecompounds are synthesized through the glycolate pathway. In leaves of wheat grown under low temperatures, relativelyhigh radioactivity was detected in ribulose 1,5-diphosphateamong the photosynthetic 14CO2-fixation products, whereas practicallyno radioactivity was detected in this compound in leaves ofwheat which had been acclimatized to high temperatures. We assumedthat the carboxylation reaction of ribulose 1,5-diphosphateis suppressed in plants acclimatized to low temperatures. It was further inferred that the C-2 and C-2 moiety of ribulose1,5-diphosphate accumulating as a result of suppression of carboxylationis converted to glycine and serine through the glycolate pathway. The possibility was also discussed that during photosyntheticCO2-fixation in wheat leaves at least a part of the C6-compoundformed by the carboxylation of ribulose 1,5-diphosphate is directlyconverted to sugar phosphate. 1Part of this investigation was reported at the 2nd InternationalCongress on Photosynthesis Research at Stresa, Italy, June 1971.This paper is based on a dissertation submitted by S.S. to theFaculty of Science, the University of Tokyo, in partial fulfilmentof the requirements for a Ph.D. degree. 2Present address: Department of Botany, Faculty of Science,University of Tokyo, Tokyo, Japan. (Received July 20, 1973; )  相似文献   
129.
The rate of ferricyanide photoreduction in broken chloroplastsisolated from leaves of wheat acclimatized to a low temperature(mean temperature, 5–7?C) was similar to that in chloroplastsfrom wheat acclimatized to a high temperature (20–25?C). There was no practical difference in glycolate oxidase activityin leaf extracts of wheat plants grown at low and high temperatures.In contrast, the ribulose diphosphate carboxylase activity ofchloroplasts from low temperature sample was less than halfthat for the high temperature sample. Chloroplasts having a high rate of photosynthetic CO2-fixationwere obtained from wheat acclimatized to a low temperature,whereas the CO2-fixation activity in chloroplasts isolated fromhigh temperature-acclimatized wheat was very low. Electron microscopy revealed that chloroplasts in high temperature-acclimatizedwheat were ellipsoidal, electron dense and contained starchgranules. Those in low temperature-acclimatized leaves wereround and did not contain starch granule. 2Present address: Department of Botany, Faculty of Science,University of Tokyo, Tokyo, Japan (Received August 7, 1973; )  相似文献   
130.
Changes in photosynthetic carbon metabolism during the glucosebleaching of Chlorella protothecoides cells were investigatedusing NaH14CO3 as tracer. Several hours after incubating thegreen algal cells in the glucose medium in the dark, the ratesof 14C-incorporation into glucose polymers and sucrose decreasedand the incorporation into the lipid fraction (fatty acids)greatly increased. At this stage, the rate of photosynthetic14CO2 fixation and the chlorophyll content were practicallythe same as in the starting green cells. Afterwards, the photosyntheticcapacity and chlorophyll content continued to decrease throughoutthe experimental period. In contrast, when photosynthetic 14CO2fixation of green cells was carried out in the medium containingglucose, the rate of 14C-incorporation into glucose polymersincreased, though there was no change in the incorporationsinto sucrose and the lipid fraction. 1Part of this investigation was reported at the Conference "ComparativeBiochemistry and Biophysics of Photosynthesis" (Japan-U.S. CooperativeScience Program) held at Hakone, Japan in 1967. 2Present address: Faculty of Agriculture, Tamagawa University,Machida-shi, Tokyo, Japan. (Received June 10, 1974; )  相似文献   
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