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941.
Rat lens beta-crystallins are internally duplicated and homologous to gamma-crystallins 总被引:1,自引:0,他引:1
The nucleotide sequence of two cloned rat lens beta-crystallin cDNAs pRL beta B3-2 and pRL beta B1-3 has been determined. pRL beta B3-2 contains the complete coding information for a beta-crystallin, designated beta B3, of 210 amino acid residues. pRL beta B1-3 is incomplete at its 5' end; the 5' codogenic information which is not present in this cDNA clone was deduced from the cloned gene. pRL beta B1-3 codes for a beta-crystallin polypeptide, designated beta B1, whose full length is 247 amino acid residues. Considerable sequence homology is noted between the amino- and carboxy-terminal halves of each protein. The two rat beta-crystallins show a substantial sequence homology with each other (60%) as well as with the published sequences of rat gamma-crystallin (37%) and bovine and murine beta-crystallins (55 and 45%). All these proteins have a two-domain structure which, like the bovine gamma II-crystallin, might be folded into four remarkably similar protein motifs. Our data further indicate that the beta-crystallins can be subdivided into two groups which are evolutionarily related. Both groups are, although more distantly, also related to the gamma-crystallins. 相似文献
942.
G T Sukhikh I V Bogdashin L V Van'ko 《Biulleten' eksperimental'no? biologii i meditsiny》1985,99(4):399-401
It has been shown that at late periods after immobilization stress there is an essential reduction in the cytostatic activity of CBA mice splenocytes detected by inhibition of mastocytoma P 815 cell proliferation in the test with 3H-uridine incorporation. The cytostatic activity returns to normal 5 to 14 days after stress. The changes in the cytolytic and cytostatic activity of mouse splenocytes following stress are correlated and a possible biological value of changes in the immunoassays for the host are discussed. 相似文献
943.
Methods for production of containerized seedlings ofAlnus species were developed which permit nitrogen-fixing nodules to form on the root systems prior to outplanting, in order to provide an early nitrogen input during seedling establishment. The methods are based on procedures for inoculating root systems with suspensions ofFrankia (Actinomycetales), applied either directly in the container cell as a soil drench at the time of seeding, or as a root dip for seedlings transplanted into the containers. Germination of dried, stored seed was enhanced by light and by presoaking for 16 h in water. Pretreatments to overcome seed dormancy or to eliminate fungal pathogens did not further enhance germination. Some loss of seedlings was recorded in the early stages of growth shortly after germination, which is a factor in calculating projected seedling yield. Nodulation and seedling growth were evaluated in terms of growth media characteristics. Seedlings performed well in peat-vermiculite, at soil pH between 5.5 and 8.0. 相似文献
944.
A striking difference in radiosensitivity was noted between C3H/He (H-2k) and C57BL/6J (H-2b) strain mice when assessed by primary anti-SRBC PFC response of intact animals and primary cell-mediated lympholysis (CML) response of spleen cells to allogeneic cells in vitro, the C3H strain being more radioresistant. On the other hand, when C3H and B6 mice were exposed to 6.62 to 10.40 grays (Gy) of x-rays and then were transplanted with 2 X 10(6) bone marrow cells from B6C3F1 (H-2b/k) donor mice within 3 hr or at 24 hr after radiation exposure, the early mortality caused by residual host-vs-graft (HVG) reaction was much higher when C3H mice were used as recipients. Furthermore, the proportion of surviving animals manifesting host-type lymphohemopoiesis, i.e., host-type revertants, was much higher in B6C3F1 to C3H than in B6C3F1 to B6 combination. Spleen cells from such host-type revertants manifested strong anti-donor reactivity when assessed by mixed lymphocyte reaction (MLR) and/or CML in vitro. Increase of radiation doses to the recipients to 10.40 Gy resulted in 100% survival and 100% donor-type lymphohemopoiesis in both groups of chimeras. These results indicate strongly that a genetic difference in radiosensitivity of immune system of the recipients can greatly influence the magnitude of residual HVG reactions observed in hybrid to parental strain bone marrow transplantation in mice. 相似文献
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Rainbow trout, Salmo gairdneri , were experimentally infected with Cryptobia salmositica . The parasitaemia was associated with increases in the size of the spleen, liver and heart (% body weight). The splenomegaly was pronounced and was often 600-fold larger. The amounts of blood lactic acid and lactic dehydrogenase in the infected and control fish were similar. However, glycogen levels of the liver, heart and epaxial muscle declined. Liver glycogen levels were most affected and decreased to values which represented 20% of the control values. The pattern of the glycogen levels of the liver, heart and epaxial muscle declined to rise to normal values by day 56 post-inoculation. Thus, the glycogen levels both paralleled the acute parasitaemia and the subsequent partial recovery of the infected fish as they tolerated a low chronic parasitaemia. 相似文献