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81.
82.
83.
A wild bean weevil,Kytorhinus sharpianus Bridwell (Coleoptera: Bruchidae), has a multivoltine life cycle and enters a hibernal larval diapause at the fourth instar
under a short daylength (Shimada & Ishihara, 1991). Here, we investigated their diapause incidence under different photoperiods
at 24°C and 27°C. The critical photoperiods for diapause induction were 14.5 h at 24°C and 14 h at 27°C. The stages susceptible
to diapause-inducing stimuli were estimated by transferring larvae of various instars from long days to short days and vice
versa. Then we investigated the incidence of larval diapause. The sensitive stage was estimated to be from the third to early
fourth instar. Though larval diapause, which was induced under a short daylength, was terminated only by increasing the daylength,
the termination was more synchronized by an exposure to a low temperature followed by increasing temperature, irrespective
of photoperiod. 相似文献
84.
Hepatic dysfunction in primary hypothyroidism 总被引:1,自引:0,他引:1
Twenty-seven patients with primary hypothyroidism were studied to evaluate the relationship between hepatic function and thyroid hormone deficiency in this disorder. In hypothyroidism, hypergammaglobulinemia was found in 71%, elevated glutamic oxaloacetic transaminase (GOT) in 48%, high lactic dehydrogenase (LDH) in 58%, hypercholesteremia in 52% and low elimination rate constant of indocyanin green (KICG) in 44%. In each criterion of liver function, these patients were divided into two groups, normal level and abnormal level group, respectively. T3 and T4 in patients with abnormal levels of GOT, glutamic pyruvic transaminase (GPT), gamma-glutamyl transpeptidase (gamma-GTP), leucine aminopeptidase (LAP), alkaline phosphatase (ALP) and 45 minutes retention rate of bromsulphalein (BSP) were not different from those in the normal level group. However, T3 and T4 in patients with abnormal levels of LDH, cholesterol, cholinesterase (ChE) and KICG were lower than those in the normal level group. The abnormal KICG group had a statistically higher cardio-thoracic ratio (CTR) than the normal group (65.7 +/- 18.8% vs 50.4 +/- 8.3%, p less than 0.05). In patients with pericardial effusion, CTR was 65.9 +/- 14.6%, while that in patients without pericardial effusion was 49.9 +/- 7.5% (p less than 0.05). These abnormalities of liver function were normalized in all cases after hormone replacement therapy. Liver biopsy in three cases disclosed normal liver in two cases and mild infiltration of monocyte into Glisson's capsule in one case.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
85.
Yoshizawa Itsuo Nagata Kyoko Ohuchi Ryoko Itoh Shinji Kanaiwa Yoshio Amiya Takashi 《Steroids》1980,36(1):87-96
Two D-homosteroids were isolated from the hydrolyzate of 5β-pregnane -3α,20α-diol disulfate (II) when it was refluxed in 3N hydrochloric acid. The structures of these steroids have been elucidated as 17α-methyl-D-homo-5β-androstane-3α, 17aβ-diol (VI) and 17α-methyl-17aγb-chloro-D-homo-5β-androstan-3α-ol (VIII) by instrumental analyses. The former was identical with a synthetic specimen derived from 5β-pregnane-3α,20β-diol di-sulfate (IV) by uranediol rearrangement. The main hydrolyzates obtained were 17α-ethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol (V) and 5β-pregnane-3α, 20α-diol (III). 相似文献
86.
Bacterial dihydropyrimidinase was shown to catalyze the hydrolytic cleavage of various 5-substituted hydantoins to the corresponding N-carbamyl-D-amino acids under alkaline conditions. Therefore, an enzymatic method for preparing the D-forms of phenylglycine-related amino acids was developed using immobilized bacterial cells with high enzyme activity. Alkalophilic bacteria were a good enzyme source for this process. The process is simple and economical for use in the production of various amino acids with the D-configuration. 相似文献
87.
Troponin in embryonic chick skeletal muscle cells in vitro. An immunoelectron microscope study 下载免费PDF全文
The fine structurel distribution of troponin on thin filaments in developing myofibrils was investigated by the use of immunoelectron microscopy. Embryonic chick skeletal muscle cells grown in vitro were treated with antibodies against each of the troponin components (troponin T, I, and C) from adult chicken muscles. Each antibody was distributed along the thin filaments with a period of 38 nm. It is concluded that these newly synthesized regulatory proteins are assembled at their characteristic position from the initial phases of myofibrillogenesis. 相似文献
88.
Masahisa Shimada 《Neurochemical research》1981,6(9):993-1003
Glucose uptake of individual structures within the brain was studied by dry-autoradiography with 2-deoxy-D-[14C(U)]glucose under mild hypoxic hypoxia (12% O288% N2 or 9% O291% N2 for 1 hr). Glucose consumption in the whole brain was estimated by combined gas chromatography-mass spectrometry (GC-MS). Mild hypoxia increased the optical density of the autoradiograph in all regions. The deuterated G-6-P (Glucose-6-phosphate) synthesized from deuterated glucose decreased significantly with 9% O2 hypoxia (P<0.05). The ratio of the deuterated G-6-P to deuterated glucose, a more appropriate indicator of glucose utilization than the concentration of deuterated G-6-P, decreased significantly with 12% O2 hypoxia (P<0.01). The hippocampus, white matter, colliculus superior, and corpus geniculatum laterale appeared to be particulary sensitive to hypoxia. 相似文献
89.
Isolation and characterization of a plaque-forming lambda bacteriophage carrying a ColE1 plasmid 总被引:3,自引:2,他引:1 下载免费PDF全文
A plaque-forming lambdaimm434 bacteriophage carrying the entire genome of colicinogenic factor E1 has been isolated and characterized. This phage, lambdaimm434ColE1, can lysogenize as a stable plasmid within a recombination-deficient Escherichia coli cell that lacks the normal attachment site for lambda phage. Furthermore, it has been found that lambdaimm434ColE1 phage carrying amber mutations in the O and P genes of the lambda genome, i.e., lambdaimm434OamPamColE1, behaves as a plaque-forming phage, and this finding suggests that the ColE1 factor DNA permits replication of the DNA of the plaque-forming phage. 相似文献
90.
Ryoko Imaichi 《Journal of plant research》1983,96(3):159-170
The third petiolar bud ofHypolepis punctata appears on the basiscopic lateral side of the petiole above the fairly developed first petiolar bud. This investigation clarified
the fact that the third bud is formed neither by the activity of the meristem of the first bud nor by the meristem directly
detached from the shoot apical meristem, but is initiated in the cells involved in the abaxial basal part of the elevated
portion of the leaf primordium. Thus the third bud is of phyllogenous origin. This investigation further revealed that the
cells to initiate the third bud are originally located in the abaxial side of the leaf apical cell complex like the cells
to initiate the first bud, but are not incorporated into the meristem of the first.
After the first, second and third petiolar buds have been initiated, they are carried up into fairly high regions on the petiolar
base by the intercalary growth which occurs in the leaf base below the insertion level of the first and the second buds. 相似文献