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911.
Oral glucose 75 g was given to 352 patients with chronic glaucoma, acute glaucoma, or ocular hypertension and 73 patients without glaucoma. The proportion of patients with shallow anterior chambers who showed an abnormal response was significantly greater than that in patients with deep anterior chambers and in the control group (p less than 0.005). The probability of developing an abnormal response to oral glucose tests increased as the depth of the anterior chamber decreased; these two variables showed a significant negative linear correlation (r = -0.79, p less than 0.001). The high prevalence of autonomic dysfunction in patients with shallow anterior chambers and glaucoma may explain this association. Because of this, acute glaucoma should be regarded as a symptom of diabetes. 相似文献
912.
S C Lee J Y Shew F H Chang M J Chou C S Yang 《Proceedings of the National Science Council, Republic of China. Part B, Life sciences》1984,8(2):143-147
Protein kinase activity has been found in hepatitis B virions (Dane particles) purified from the plasma of hepatitis B surface antigen carriers [Albin, C., and Robinson, W.S. (1980) J. Virol. 34, 297-302]. Dane particles were purified from the pooled, HBeAg-positive plasma. When this preparation was incubated with [gamma 32P]ATP in the presence of 10mM MnCl2 and 0.5% NP-40 for 15 seconds at 30 degrees C, several phosphorylated polypeptides of 20,000, 42,000, 48,000, 50,000 and 56,000 daltons were detected in sodium dodecyl sulfate-polyacrylamide gels. When the Dane particles were incubated with [gamma 32P]ATP, 10 mM MnCl2, and 0.5% NP-40 in the presence of human hepatoma cell (J-5) particulate fraction at 30 degrees C, 15 seconds, the 42,000, 48,000 and 50,000 daltons phosphorylated polypeptides were not found. When human peripheral blood lymphocytes particulate fraction was incubated with Dane particles under the same conditions, no change of Dane particle phosphorylated polypeptides was detected. Previous publications [Albin, C., and Robinson, W.S. (1980) J. Virol. 34, 297-302; Gerlich, W.H. et al. (1982) J. Virol. 42, 761-766] showed that when hepatitis B core particles purified from hepatoma tissues contained protein kinase activity, only phosphorylated polypeptide was 20,000 daltons. Our data suggested that when Dane particles were put in an environment of hepatoma cells (or tissues), the protein kinase could only phosphorylate selected polypeptides in these particles. 相似文献
913.
A simple enucleation technique that facilitates autoradiographic and electron microscopic examination of cytoplasms is described. Cells were grown on commercially available plastic Leighton coverslips and these were centrifuged in the presence of cytochalasin B. The centrifugation requires no special holders and only a high speed centrifuge. Enucleation frequencies of greater than 90% were obtained for Chinese hamster fibroblasts and mouse B-82 cells. 相似文献
914.
To determine whether histone genes are coordinately regulated, histone mRNA concentrations were measured in exponentially growing L6 myoblasts, S-phase synchronized myoblasts and in differentiating myoblasts. The levels of various histone mRNA subspecies declined rapidly and coordinately once myoblasts were given the signal to differentiate. mRNA levels were reduced on average to 1-5% of the amount observed in exponentially growing cells by 48 h after the signal to differentiate. The reductions occurred in concert with the cessation of DNA synthesis as the cells differentiated. Inhibition of DNA synthesis by treating myoblasts with Ara-C or hydroxyurea resulted in a histone mRNA half-life of 10-13 min for each of the histones examined. One example of non-coordinate regulation was observed however among the H4 mRNA subspecies in S-phase synchronized cells. The levels of two major subspecies of H4 mRNA increased coordinately in S-phase compared to levels observed in cells growing exponentially. A third subspecies of H4 mRNA on the other hand was found to decline by 50%. These studies suggest that the majority of histone mRNA subspecies are under coordinate control, although one exception has been noted among the subspecies of histone H4. 相似文献
915.
R.E. Jonkers B. Oosterhuis R.J.M. Ten Berge C.J. Van Boxtel 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,233(1):249-255
A relatively simple assay with improved reliability and sensitivity for measuring levels of 6-mercaptopurine in human plasma is presented. After extraction of the compound and the added internal standard with phenyl mercury acetate, samples were separated by ion-pair reversed-phase high-performance liquid chromatography. On-line the analytes were oxidized to fluorescent products and detected in a flow-fluorimeter. The within-day coefficient of variation was 3.8% at a concentration of 25 ng/ml. The lower detection limit was 2 ng/ml when 1.0 ml of plasma was used. Mercaptopurine concentration versus time curves of two subjects after a single oral dose of azathioprine are shown. 相似文献
916.
The DNA of fifteen Italian cultivars of durum wheat (Triticum turgidum L. ssp. durum) were analyzed by in fluorescence amplified fragment length polymorphism (fAFLP) in order to obtain the characteristic fingerprintings
of genotypes and assess their genetic relatedness. Among 64 combinations of fluorescence labelled primers, three different
combinations were chosen as producing a total of 6630 AFLP fragments, 2277 (34.3 %) of them being polymorphic. By using this
fAFLP methodology a DNA fingerprinting of each durum wheat cultivar was generated for genotype identification. Analysis of
the genetic relationships show the low variability among durum wheat cultivars. 相似文献
917.
O. S. Mashkina T. M. Tabatskaya A. I. Gorobets K. A. Shestibratov 《Applied Biochemistry and Microbiology》2010,46(8):769-775
Conditions of cultivation and micropropagation of selected biotypes of five willow species (Salyx dasyclados Wimm., S. caspica Pall., S. triandra L., S. purpurea L., and S. viminalis L.) and two hybrids (×S. acuminata S. and ×S. palustris Host.) were optimized. Data on in vitro propagation of S. caspica, S. triandra, S. purpurea together with hybrids S. acuminata and S. palustris were obtained for the first time. It has been demonstrated that the outcome of cultivation and propagation of willows strongly
depends on genotypic peculiarities of initial plants. The optimal terms of isolation and sterilization of single-node segments
for obtaining 50–75% of aseptic viable developing cultures were estimated. The nutritive media were selected providing induction
of stem development (to 67%), their rooting (to 91%), elongation (to 3–6 cm), and multiplication (propagation coefficient
of 4). The designed method (adopted to different genotypes) can be applied for obtaining aseptic in vitro cultures serving
as initial plant material for genetic transformation and mass propagation of plants with new agriculturally valuable characteristics
which are of interest for construction of bioenergetic plantations and for needs of the paper industry. 相似文献
918.
919.
Control of breathing in Sherpas at low and high altitude 总被引:2,自引:0,他引:2
Hackett P. H.; Reeves J. T.; Reeves C. D.; Grover R. F.; Rennie D. 《Journal of applied physiology》1980,49(3):374-379
920.