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41.
Telokin, an acidic protein related to the C-terminal portion of smooth muscle myosin light chain kinase from turkey gizzard has been crystallized in a form suitable for a high-resolution diffraction analysis. The crystals were grown from solutions of polyethylene glycol 8000 using the hanging-drop vapor diffusion method. They belong to the trigonal space group P3(1)21 or P3(2)21 with cell parameters a = 64.0 A, c = 59.4 A and diffract to at least 2.7 A resolution.  相似文献   
42.
Senescence-accelerated mice (SAM) are one of the animal models used for studying senescence, which consist of several substrains such as SAM-R/1, R/2, P/1, P/2. SAM-R/1/Eis maintained in Eisai Tsukuba Research Laboratories, Ibaraki, Japan, was originally introduced as a substrain of a normal control SAM-R/1 from Kyoto University, Japan. We have noted signs of convulsions in SAM-R/1/Eis mice during routine animal care, particularly while changing cages. We identified the clinical signs and determined the concentrations of glucose and immunoreactive insulin in plasma of SAM-R/1/Eis mice. There were no differences in the male:female ratios of mice showing prodrome only, grand mal, or no-signs. The ages at which prodrome and grand mal were first noted peaked between 20 and 25 weeks. Concentrations of glucose and immunoreactive insulin in plasma did not indicate the mice were in insulin hypoglycemia, which is one cause of convulsions. AKR strain mice, some of which originated with the SAM strain are known to become convulsive by repeated "throwing" stimulations. Conversely, in SAM-R/1/Eis, throwing stimuli are not needed to cause convulsive signs. Thus it is likely that in SAM-R/1/Eis mice the signs are triggered by repeating mild environmental changes, such as changing cages. The results of this study show that SAM-R/1/Eis is neither a normal control strain, nor an original SAM-R/1 strain. But it is possible that SAM-R/1/Eis is another useful animal model for studying spontaneous convulsion.  相似文献   
43.
Summary Lipase was modified with several hydrophilic and hydrophobic synthetic polymers. The modified lipase was solubilized into chloroform by. The catalytic esterification activity of modified lipase increased linearly with the increase of its solubility in chloroform.  相似文献   
44.
Angeloylcumambrin-B, a new antimicrobial guaianolide sesquiterpene lactone, was isolated from Chrysanthemum ornatum and the structure was determined by a combination of chemical and physical methods.  相似文献   
45.
Four known sesquiterpene lactones, tomentosin, ivalin, 4-epi-isoinuviscolide and gaillardin, together with three new lactones, inuchinenolides A, B and C, were identified in the whole plant of Inula britannica var. chinensis.  相似文献   
46.
Peyer's patches in normal adult mice, neonatally thymectomized mice and mice injected with hydrocortisone were studied qualitatively and quantitatively by light microscopy. The patch was divided into germinal center, follicular area, parafollicular area and dome area. In normal mice, the volumetric ratio of the germinal center to the entire patch was 30.9%; that of the follicular area, 33.3%; that of the parafollicular area, 27.7%; and that of the dome area, 8.2%. Thymus-dependent small lymphocytes were 40% of small lymphocytes in the patch. Out of the total thymus-dependent small lymphocytes in the patch, 13% were included in the germinal center; 19%, in the follicular area; 62%, in the parafollicular area; and 6%, in the dome area. Hydrocortisone-sensitive small lymphocytes were 65% of the total small lymphocytes in the patch, the germinal center contained 9%; the follicular area, 84%; the parafollicular area, 2%; and the dome area, 5%. The epithelium over the dome area was invaded by numerous small lymphocytes. Forty-eight percent of lymphocytes within the epithelium over the dome were thymus-dependent and 67% were hydrocortisone-sensitive. It is concluded that Peyer's patch may be considered as a peripheral lymphatic tissue, functionally as well as morphologically.  相似文献   
47.
Unusual base sequence arrangement in phage phi 29 DNA.   总被引:9,自引:0,他引:9  
J Ito  R J Roberts 《Gene》1979,5(1):1-7
Susceptibility of Bacillus subtilis phage phi 29 DNA to 34 different restriction endoculceases was determined. Three enzymes, BglI, XbaI and BstEII, were found to cleave phi 29 DNA only once at specific sites. The sites of these single cleavages have been mapped. Thirteen enzymes did not cut phi 29 DNA. phi 29 HindIII DNA fragments inserted into pBR313 plasmid and propagated in Escherichia coli, were resistant to these restriction endonucleases. This result suggests that the insusceptibility is due to the absence of the nucleotide sequences on phi 29 recognized by the enzymes, and not to the presence of modified nucleotides.  相似文献   
48.
49.
The cancer/testis antigens (CTAs), New York esophageal squamous cell carcinoma-1 (NY-ESO-1) and melanoma antigen gene (MAGE)-A4 are normally restricted to male germ cells but are aberrantly expressed in several cancers. Considering the limited information regarding their significance in osteosarcoma (OS), the purpose of this study was to determine the clinical significance of NY-ESO-1 and MAGE-A4 expression in OS. Nine patients with OS treated at Kindai University Hospital were included in the study. The median age was 27 years, and median follow-up period was 40 months. The specimens obtained at the time of biopsy were used to perform immunostaining for NY-ESO, MAGE-A4, p53, and Ki-67. The positive cell rates and positive case rates of NY-ESO, MAGE-A4, p53, and Ki-67 were calculated. The correlation between the positive cell rate of immunohistochemical markers was also calculated. The correlation between the positive cell rate of NY-ESO-1 or MAGE-A4 and tumor size or maximum standardized uptake (SUV-max) was also determined. The positive cell rates of NY-ESO-1 or MAGE-A4 in continuous disease-free (CDF) cases were also compared with those in alive with disease (AWD) or dead of disease (DOD) cases. The average positive cell rates of NY-ESO, MAGEA4, p53, and Ki-67 were 71.7%, 85.1%, 16.2%, and 14.7%, and their positive case rates were 33.3%, 100%, 44.4%, and 100%, respectively. The positivity rates of NY-ESO-1 and p53 were strongly correlated, whereas those of NY-ESO-1 and Ki-67 were moderately correlated. The MAGE-A4 and p53 positivity rates and the MAGE-A4 and Ki-67 positive cell rates were both strongly correlated. The NY-ESO-1 and MAGE-A4 positivity rates were moderately correlated. The positive correlation between the NY-ESO-1 positive cell rate and tumor size was medium, and that between the MAGE-A4 positivity rate and SUV-max was very strong. There was no significant difference in the positive cell rates of NY-ESO-1 or MAGE-A4 between CDF cases and AWD or DOD cases. Overall, our results suggest that NY-ESO-1 and MAGE-A4 may be involved in the aggressiveness of OS.Key words: New York esophageal squamous cell carcinoma-1 (NY-ESO-1), melanoma antigen gene (MAGE)- A4, osteosarcoma, prognosis, cancer/testis antigen (CTA), immunohistochemistry  相似文献   
50.
Influenza A viruses can be isolated from a variety of animals, but their range of hosts is restricted. For example, human influenza viruses do not replicate in duck intestine, the major replication site of avian viruses in ducks. Although amino acids at positions 226 and 228 of hemagglutinin (HA) of the H3 subtype are known to be important for this host range restriction, the contributions of specific amino acids at these positions to restriction were not known. Here, we address this issue by generating HAs with site-specific mutations of a human virus that contain different amino acid residues at these positions. We also let ducks select replication-competent viruses from a replication-incompetent virus containing a human virus HA by inoculating animals with 1010.5 50% egg infectious dose of the latter virus and identified a mutation in the HA. Our results showed that the Ser-to-Gly mutation at position 228, in addition to the Leu-to-Gln mutation at position 226 of the HA of the H3 subtype, is critical for human virus HA to support virus replication in duck intestine.  相似文献   
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