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1.
Factors associated with the basal level of serum thyrotropin (TSH) were analyzed over a wide range of pathophysiological conditions by means of a large laboratory database on thyroid function. When data were analyzed two-dimensionally, serum TSH showed significant inverse correlations with total triiodothyronine (T3), free T3 index (FT3I), total thyroxin (TT4) and free T4 index (FT4I) in the order of increasing intensity. The three-dimensional analysis, however, revealed that 1) total hormone levels were actually unrelated to serum TSH when the levels of free hormone indices were held constant, 2) the relation between FT3I and TSH became obscure when the influence of FT4I was similarly removed. On the other hand, 3) the relation of FT4I with TSH was unaffected by the level of FT3I. These results suggest that free T4 is the main determinant of the serum TSH level. This study also implies that it is possible to use large amounts of laboratory data to elucidate the overall profile of a given patho-physiological system, whose structure is only partially revealed by conventional clinical or animal studies. 相似文献
2.
3.
Prof. Katsuko Kataoka Junko Miura Yasuko Takeoka Yoshisuke Kusumoto Noboru Yanaihara 《Cell and tissue research》1985,239(3):531-535
Summary Ontogenesis of gastrin cells was studied in the pyloroduodenal mucosa of the mouse using anti-human G17 serum, R-1301, and anti-human G34(1–15) serum, R-2703. R-1301-immunostained cells first appeared in the pyloric mucosa of 14-day-old fetuses. Cells stained with both R-1301 and R-2703 appeared immediately after birth, and gradually increased in number to the adult level. Most R-1301-reactive cells were also reactive to R-2703, whereas some cells that reacted with R-1301 exhibited very weak or no reaction with R-2703. The discrepancy between these two immunoreactivities is discussed.In the duodenum, a considerable number of R-1301-reactive cells were present from the perinatal stage and through out adult development. A few R-2703-reactive cells were seen in the duodenum of young mice but not of the adult. 相似文献
4.
Hidetaka Kosako Yukiko Gotoh Eisuke Nishida 《Development, growth & differentiation》1996,38(6):577-582
Mitogen-activated protein kinase (MAPK) was originally identified as a serine/threonine protein kinase that is rapidly activated in response to various growth factors and tumor promoters in mammalian cultured cells. The kinase cascade including MAPK and its direct activator, MAPK kinase (MAPKK), is now believed to transmit various extracellular signals into their intracellular targets in eukaryotic cells. It has been reported that activation of MAPKK and MAPK occurs during the meiotic maturation of oocytes in several species, including Xenopus laevis . Studies with neutralizing antibodies against MAPKK, MAPK phosphatases and constitutively active MAPKK or MAPK have revealed a crucial role of the MAPKK/MAPK cascade in a number of developmental processes in Xenopus oocytes and embryos. 相似文献
5.
In the present study, anti-metastatic effect of Z-100 on the spontaneous pulmonary metastases of Lewis lung carcinoma (3LL)
was examined in an attempt to regulate suppressor T cells. When Z-100 (10 mg/kg) was daily injected i.p. after 3LL inoculation,
survival rate of these mice was increased significantly (p<0.05). In addition, the number of pulmonary metastatic colonies of 3LL in Z-100-treated mice were significantly decreased
by 38% at 21 days, as compared with that of control mice (p<0.05). Along with the decrease of pulmonary metastases, suppressor cell activity was also gradually reduced in these mice,
as compared with that of control mice. When splenic suppressor cells (5×107 cells) from 3LL-bearing mice were adoptively transferred into normal mice (recipients) just before inoculation of 3LL, the
development of pulmonary metastases in recipients was significantly accelerated. However, splenocytes from 3LL-bearing mice
treated with Z-100 did not affect the development of pulmonary metastasis. The potential to accelerate the metastasis of splenic
mononuclear cells from 3LL-bearing mice was decreased significantly by the treatment with anti-Thy 1.2 monoclonal antibody
(mAb), anti-Lyt 2.2 mAb or anti-CD11b mAb followed by complement. IL-4 activity in the sera of 3LL-bearing mice was detected
15 days after tumor inoculation (13 pg/ml) and gradually increased (18 pg/ml) 20 days after tumor inoculation. However, when
Z-100 (10 mg/kg) was daily injected i.p., IL-4 activity in sera was decreased significantly, and the IL-4 activity was not
detected in these mice on day 20. These results suggest that Z-100 could inhibit the pulmonary metastases in 3LL-bearing mice
through the inhibition of suppressor T cell activity and a possible candidate of its effector molecule, IL-4. 相似文献
6.
K. Terasawa A. Sakai Y. Yanagidaira M. Takeoka K. Asano T. Fujiwara K. Yanagisawa O. Kashimura G. Ueda 《International journal of biometeorology》1995,38(3):126-130
To examine cardiopulmonary function during exercise in a mountainous region at moderate altitude, we measured cardiac frequency, oxygen consumption
, and percentage arterial hemoglobin oxygen saturation (%SaO2) before and after a bicycle race with a starting point at 638 m and finishing point at 1980 m. The time required to ascend an elevation of 10 m was prolonged with increasing altitude, and heart rate also increased with altitude. The %SaO2 at the starting point and at the finishing point differed significantly (P<0.01). Faster cyclists exhibited higher %SaO2 and lower
, while slower cyclists exhibited a reduction in %SaO2 and an increase in
immediately after the race. The %SaO2 recovery time was significantly correlated with the racing time (r=0.54,P<0.001). Therefore, the faster cyclists' oxygen debt upon completion of the race may be small and recovery of cardiopulmonary function may be fast, while the slower cyclists' oxygen debt may be large and recovery of cardiopulmonary function may be slow. 相似文献
7.
Two soluble glycoproteins containing hydroxyproline were extractedfrom cultured tobacco cells (cell line XD-6S) and purified byion-exchange and gel-filtration chromatography. On DEAR-cellulosecolumn chromatography in the final step of the purification,one was eluted at 90 mM NaCl and the other at 120 mM as singlepeak. Both purified glycoproteins were also sedimented as singlepeak with an ultracentrifugation. The S20,w values were 6.1for the former and 7.0 for the latter. These glycoproteins were composed of 94% polysaccharide and6% protein in the former, and 87% polysaccharide and 13% proteinin the latter. The sugar moiety consisted of galactose, arabinose,rhamnose, and uronic acid in both. Hydroxyproline accountedfor 12% in the former and 20% in the latter amino acid composition.A high content of alanine in both (14 and 15%) was one of thedistinctive characteristics of these soluble glycoproteins. These intracellular soluble hydroxyproline-containing glycoproteinswere not labelled within 30 min of incubation with 3H-proline,although the radioactivity was rapidly incorporated (within15 min) into the intracellular macromolecules. (Received February 21, 1978; ) 相似文献
8.
Annual production rates of reproductive organs inFagus crenata forests in the lower area of the species' range were studied using 10 litter traps in 1980–1986. The production rates of
dispersed pollen were estimated by multiplying the number of fallen male inflorescences per ha per year by the mean amount
of pollen per inflorescence before anthesis. Large annual fluctuations in the production rates of male and female inflorescences
were recognized, whereas their annual trends were synchronized with each other. Pollen production rates were within the range
1.0–6900 (mean: 1630)×109ha−1 yr−1, the maximum/minimum ratio attaining 7000.F. crenata was the lowest producer of pollen among seven tree species studied: the number of pollen grains equivalent to a single ovule
was in the range 6.0–14×104. Furthermore, the mean dry weight of a single pollen grain (3.77×10−5mg) was higher than for wind-pollinated species. Three factors seemed to cause the low seed fertility ofF. crenata. The dry-matter production rate in the best seed year reached 3252 kg ha−1 yr−1, of which pollen accounted for 259 kg ha−1 yr−1. Unproductive years with less than 10% of the maximum production occurred four times in a 7-yr period. In such years there
were fewer male and female inflorescences, and more fruit dropped as a result of insect damage. Lower nut dissemination would
play an important role in suppressing any increase in nut predators, and fewer flowers would be produced to avoid wastage
of photosynthates in a cool-temperate climate. 相似文献
9.
Solvent polarity effects on supramolecular chirality of a polyfluorene‐thiophene copolymer 下载免费PDF全文
Takashi Hirahara Masahiro Yoshizawa‐Fujita Yuko Takeoka Masahiro Rikukawa 《Chirality》2018,30(6):699-707
This study demonstrates the supramolecular chirality control of a conjugated polymer via solvent polarity. We designed and synthesized a chiral polyfluorene‐thiophene copolymer having two different chiral side chains at the 9‐position of the fluorene unit. Chiral cyclic and alkyl ethers with different polarities were selected as the chiral side chains. The sign of the circular dichroism spectra in the visible wavelength region was affected by the solvent system, resulting from the change of supramolecular structure. The estimation of the solubility parameter revealed that the solubility difference of the side chains contributed to the change of the circular dichroism sign, which was also observed in spin‐coated films prepared from good solvents having different polarities. 相似文献
10.
Seno T Hamaguchi M Ashihara E Kohno M Ishino H Yamamoto A Kadoya M Nakamura K Murakami K Matoba S Maekawa T Kawahito Y 《PloS one》2011,6(10):e25541