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Summary The variation of X-ray sensitivity was investigated during the cell cycle. The cells were most sensitive during the S phase and less sensitive during the G2- and G1 phase. Furthermore, the repair of X-ray damage was investigated in stationary (plateau phase) cells. The cells of both lines were able to repair damage to nearly the same extent.
Supported (I-IV) by the Deutsche Forschungsgemeinschaft (Mi/100, 1-7). 相似文献
Zusammenfassung Die Variation der Strahlensensibilität während des Zellcyclus wurde untersucht. Die Zellen reagierten am sensibelsten in der S-Phase, weniger sensibel in der G2-und G1-Phase. Weiterhin wurde die Reparation von Strahlenschäden bei stationären (Plateauphase-)Zellen untersucht. Die Zellen beider Linien sind in etwa gleichem Maße reparationsfähig.
Supported (I-IV) by the Deutsche Forschungsgemeinschaft (Mi/100, 1-7). 相似文献
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Two truncated Bacillus thuringiensis crystal protein genes, belonging to the classes cryIA(b) and cryIC and both coding for insecticidal N-terminal fragments of the corresponding crystal proteins, were translationally fused. Expression of the gene fusion in Escherichia coli showed a biologically active protein with a toxicity spectrum that overlapped those of both contributing crystal proteins. 相似文献
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A study was made of the changes in the content of essential oil and its components (farnesene, (-)-α-bisabolol, (-)-α-bisabololoxide
A, (-)-α-bisabololoxide B and spathulenol, α-bisabolonoxide A, chamazulene, cis en-in-dicycloether) and of the number of secretory
canals in the receptacles during the beginning of flowering, full flowering and the termination of flowering of camomile anthodia.
The total content of the essential oil was highest during the beginning of flowering and lowest during its termination. The
proportion of the individual sesquiterpenes in the essential oil underwent changes mostly during the beginning and termination
of flowering. The number of secretory canals in the basal and middle anthodial parts increased during the beginning of flowering
and the full flowering. 相似文献
7.
Mag. rer. nat. Alois Lametschwandtner Peter Simonsberger Hans Adam 《Cell and tissue research》1977,180(4):433-442
The angioarchitecture of the neural stalk and the encephaloposthypophysial portal system of the hypophysis of the toad, Bufo bufo (L.), was studied using three different methods. The neural stalk is mainly supplied by branches of the arteria infundibularis superficialis which form a widemeshed vascular network. Dorsally this network continues into the plexus of the pars nervosa. The vascularization of the pars nervosa is made up of the encephalo-posthypophysial portal system. This portal system consists of a hypothalamic branch (=portion), a mesencephalic and a mesencephalicbulbar branch (=portion). The hypothalamic branch was found to drain the pars ventralis of the tuber cinereum as well as more dorsal regions of the diencephalon. The mesencephalic-bulbar trunk enters the hypothalamic branch. The resulting common stem of the encephalo-posthypophysial portal vein the curves around the retroinfundibular communicating artery, crosses its ventral side and runs caudally. The secondary capillary plexus of the pars nervosa is characterized by well defined capillary plexus of the pars nervosa is characterized by well defined capillary networks which are located at the periphery of the parenchyma of the pars nervosa, thus forming a rostral, dorsal and ventro-caudal net. The central region of the parenchyma of the pars nervosa is supplied only by main branches of the encephalo-postpophysial portal vein. The venous drainage of the pars nervosa is via the vena hypophysea transversa. 相似文献
8.
Antifreeze protein produced endogenously in winter rye leaves 总被引:30,自引:0,他引:30
After cold acclimation, winter rye (Secale cereale L.) is able to withstand the formation of extracellular ice at freezing temperatures. We now show, for the first time, that cold-acclimated winter rye plants contain endogenously produced antifreeze protein. The protein was extracted from the apoplast of winter rye leaves, where ice forms during freezing. After partial purification, the protein was identified as antifreeze protein because it modified the normal growth pattern of ice crystals and depressed the freezing temperature of water noncolligatively. 相似文献
9.
Michael C. Iannuzzi Robert C. Stern Francis S. Collins Catherine Tom Hon Noriko Hidaka Theresa Strong Lisa Becker Mitchell L. Drumm Marga B. White Bernard Gerrard Michael Dean 《American journal of human genetics》1991,48(2):227-231
Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. We have identified in exon 7 two frameshift mutations, one caused by a two-nucleotide insertion and the other caused by a one-nucleotide deletion; these mutations--CF1154insTC and CF1213delT, respectively, are predicted to shift the reading frame of the protein and to introduce UAA(ochre) termination codons at residues 369 and 368. 相似文献
10.
Summary
sev
LY3,the only existing allele at thesev locus (1–33,2±0,2), behaves as strongly hypomorph or even as amorph. Ommatidia in asev compound eye have only seven receptor cells, the position of the R7 pattern element being vacant. Various criteria showing that the missing cell is R7 have been verified. These include (i) anatomical characteristics ofsev ommatidia; (ii) behaviour of central R cells insev rdgB double mutants; (iii) medullary projection of central R cell axons; and (iv) mitotic pattern ofsev imaginal discs. The analysis of morphogeneticsev-sev
+ mosaics has shown thatsev is expressed autonomously by R7 cells, indicating that thesev phenotype is not due to asev genotype of ommatidial pattern elements other than R7. The study of third instarsev imaginal discs has not brought any direct evidence for death of clustered presumptive R7 cells; however, clonal analysis of the developingsev compound eye has given evidence of developmental parameters comparable to those ofsev
+, therefore favouring the hypothesis that R7 cells die insev mutants. On the other hand,sev
+ seems to be required for the determination of the R7 cells, since thesev phenotype cannot be uncovered during the last mitoses of heterozygous mutant cells. 相似文献