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31.
32.
The proximal portions of axons of large anterior-horn cells were investigated in the lumbar cords of 10 normal human autopsy cases. Light-microscopically, 81 myelinated axons were observed to be connected with the cell body. Of the 81 axons, 78 emanated from the cell body and 3 others originated in the proximal part of primary dendrites. As for normal-looking neurons (n = 77), the length of the axon hillock plus initial segment was 64.0 +/- 12.3 microns (average +/- SEM), ranging from 47.5 to 110.0 microns, while the diameter of the thinnest portion of the initial segment was 2.40 +/- 0.30 microns (average +/- SEM), ranging from 1.32 to 3.92 microns. Electron-microscopically, the predominant organelles of the axon hillock were mitochondria, neurofilaments which merged into the axon and occasional granular endoplasmic reticulum. A few synaptic boutons were found on the surface of the axon hillock. The cell membrane of the initial segment consisted of a layer of electron-dense material (undercoating). The cytoplasm contained many neurofilaments, running parallel to the longitudinal axis of the initial segment. Among the neurofilaments, lysosomes, smooth endoplasmic reticulum, dense bodies and vesicular profiles as well as mitochondria were seen. At the beginning of the myelin sheath, the axoplasm contained mitochondria, many neurofilaments and occasional lysosomes. 相似文献
33.
Kunihiko Kimura Yutaka Takahashi Masayoshi Konishi Sotaro Iwamoto 《Primates; journal of primatology》1981,22(1):119-130
On the basis of 44 hindlimbs of 14 male and 14 female crab-eating monkeys (Macaca fascicularis), the morphology of the adductor muscles of the thigh was described and some functional indices were calculated. The results
obtained from this study agreed generally with those of otherMacaca species reported by various authors. For the classification and nomenclature of the adductors, the criteria proposed byUhlmann (1967, 1968) was well adapted to the crab-eating monkey. The adductors comprise the m. gracilis, m. pectineus, m. adductor
longus, pars longa and pars brevis of m. adductor brevis, pars lata and pars minima of m. adductor magnus and m. obturatorius
externus. In males, the adductors are generally inserted further down the femur, and the insertions of pars brevis of the
m. adductor brevis and pars minima of the m. adductor magnus have longer attachments to the femur than in females. The arrangement
of each adductor muscle and of each fasciculus of a thigh muscle may invoke a principle of organization. 相似文献
34.
The concept of mass balance was used to analyze the metabolic pathways of citrate production by Candida lipolytica from glucose. Specific rates of glucose consumption, citrate and isocitrate productions, carbon dioxide evolution, and cellular syntheses of protein and carbohydrate were observed in an NH4+-limited chemostat culture. These data permitted one to assess the carbon flux in vivo by solving simultaneous carbon balance equations with respect to intermediary metabolite pools in the steady State. Among the three models considered here, model I (which coordinates the pyruvate carboxylation with the tricarboxylic acid cycle, but disregards the glyoxylate cycle) was considered plausible because the carbon flux calculated so far was acceptable. On the other hand, models II and III (which overlook the pyruvate carboxylation and the 2-oxoglutarate dehydrogenation, respectively) were found to be most unlikely because of the unusual flux assessed from these models. 相似文献
35.
36.
Atsuo Tanaka Takeshige Hagihara Yoshiki Nishikawa Masayoshi Mishina Saburo Fukui 《Applied microbiology and biotechnology》1976,3(2):115-124
Summary The effects of cerulenin, an anti-lipogenic antibiotic, on the growth and cellular fatty acid composition ofCandida lipolytica were investigated by changing the chain length of n-alkane, the growth substrate. The antibiotic inhibited almost completely the growth of the yeast on glucose, n-undecane and n-dodecane, but partly that on n-tridecane. The yeast growth on longer alkanes, e.g., from n-tetradecane to n-octadecane, was not affected by this antibiotic, indicating that a chain elongation system and/or intact incorporation system predominantly operate in the formation of cellular fatty acids from such longer chain n-alkanes. Comparison of the fatty acid profiles between the cells grown on n-alkanes of different chain lengths, especially on n-pentadecane, in the presence and absence of cerulenin, supported the supposition that only the de novo synthesis system of the yeast would be affected by the antibiotic, whereas the chain elongation system would not. 相似文献
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Yuya Nitta Yoshihiro Ueda Seiya Murata Masaru Isono Shingo Ohira Akira Masaoka Shoki Inui Hayate Washio Reimi Yoshinaka Tomohiro Sagawa Masayoshi Miyazaki Teruki Teshima 《Reports of Practical Oncology and Radiotherapy》2022,27(5):809
BackgroundWe evaluated the setup error and dose absorption of an immobilization system with a shell and wooden baseplate (SW) for lung stereotactic body radiotherapy (SBRT).Materials and methodsSetup errors in 109 patients immobilized with an SW or BodyFix system (BF) were compared. Dose attenuation rates of materials for baseplates were measured with an ion-chamber. Ionization measurements were performed from 90° to 180° gantry angle in 10° increments, with the ball water equivalent phantom placed at the center of the wood and carbon baseplates whose effects on dose distribution were compared using an electron portal imaging device.ResultsThe ratio for the anterior-posterior, cranial-caudal, and right-left of the cases within 3-mm registered shifts in interfractional setup error were 90.9%, 89.2%, and 97.4% for the SW, and 93.2%, 91.6%, and 98.0% for the BF, respectively. For intrafractional setup error, 98.3%, 97.4%, and 99.1% for the SW and 96.6%, 95.8%, and 98.7% for the BF were within 3-mm registered shifts, respectively. In the center position, the average (minimum/maximum) dose attenuation rates from 90° to 180° for the wooden and carbon baseplates were 0.5 (0.1/2.8)% and 1.0 (–0.1/10.1)% with 6 MV, respectively. The gamma passing rates of 2%/2 mm for the wooden and carbon baseplates were 99.7% and 98.3% (p < 0.01).ConclusionsThe immobilization system with an SW is effective for lung SBRT since it is comparable to the BF in setup accuracy. Moreover, the wooden baseplate had lower radiation attenuation rates and affected the dose distribution less than the carbon baseplate. 相似文献
39.
Lan Phi NT Nishiyama C Choi HS Sawamura M 《Bioscience, biotechnology, and biochemistry》2006,70(8):1832-1838
The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by gamma-terpinene (5.30%), myrcene (2.25%) and alpha-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, alpha-pinene, beta-pinene, limonene, nonanal, gamma-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 3(6)), whereas beta-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil. 相似文献
40.
Satoshi Oguchi Hiroyuki Saito Masayoshi Tsukahara Haruhiko Tsumura 《Cytotechnology》2006,52(3):199-207
Controlling cell proliferation during cell culturing is an effective way to improve the production yield in mammalian cell
culture. We examined the effect of temperature shifts (TS) under pH control conditions in Chinese hamster ovary cells. When
we shifted the culture temperature from 37 °C to 31 °C before a stationary phase at pH 6.8 (TS/pH 6.8), cell viability remained
high, and the final human monoclonal antibody (hMab) concentration increased to 2.3 times that in the culture remaining at
37 °C. However, there were no significant effects on the cell viability or production yield with the same TS at pH 7.0 (TS/pH
7.0). The average specific hMab productivity and mRNA level of TS/pH 7.0 were the same as that of TS/pH 6.8. The control of
cell growth by the TS or the addition of rapamycin was effective in the maintenance of cell viability, but there was no significant
increase of the average specific hMab productivity in the culture where cell proliferation was controlled with rapamycin.
The hMab mRNA concentration decreased to 55%–65% at a 37 °C culture with the addition of actinomycin D. In contrast, actinomycin
D did not affect the mRNA level in the TS culture. This result suggested that the increase in the mRNA level in the TS condition
was caused by an increase in mRNA stability. In this study, we show that TS can produce two unrelated effects: a prolongation
of cell longevity and an improvement in mRNA stability. 相似文献