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1.
Restriction endonuclease fragment length polymorphisms (RFLPs) were found using the cDNA probe Hox-2.1 for the homeo box-2.1 gene in the mouse. Polymorphism was detected in restriction patterns generated by fragments fromHindIII digestion. The great majority of laboratory strains of mice carries theHox-2.1 a allele. Only two laboratory strains carry theHox-2.1 b allele. Among strains of wild origin, the European subspecies (Mus m. domesticus, M. m. brevirostris, andM. m. musculus) and some Asian subspecies (M. m. castaneus) carry theHox-2.1 a allele. The subspecies from Far Eastern countries (M. m. molossinus, Chinese mice of wild origin, andM. m. yamashinai) carry theHox-2.1 ballele. Using the RFLP, theHox-2.1 gene was mapped on chromosome 11. Three-point cross test data showed that the recombination frequency is 29.6% between theHba and theHox-2.1 genes and 23.5% between theHox-2.1 and theEs-3 genes. The gene order ofHba-Hox-2.1-Es-3 has been confirmed.  相似文献   

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13 taxa belonging to 4 “species groups” ofGalium L. sect.Aparinoides (Jord.)Gren. produce 15 leaf flavonoids: Apigenin-7-diglucoside, Luteolin-7-monoglucoside and 7-diglucoside, Diosmetin, Diosmetin-7-monoglucoside and 7-diglucoside; Kaempferol-3-rutinoside, Kaempferol-3,7-diglucoside, Quercetin, two Quercetin-3-monoglycosides, Rutin, Quercetin-3-rutinoside-7-glucoside, Quercetin-7-glycoside and an unidentified aglycone. TheG. trifidum, G. obtusum andG. palustre groups (with the exception of theG. tinctorium subspecies andG. elongatum) have similar flavone-flavonole patterns, while theG. antarcticum group produces a specific pattern. Leaf flavonoids of theG. trifidum andG. antarcticum group are inhomogenous, becauseG. tinctorium subsp.tinctorium andG. antarcticum lack flavones. For all taxa (with the exception of those of theG. antarcticum group) intraspecific variation is demonstrated, and 4 populations ofG. trifidum subsp.trifidum, G. tinctorium subsp.tinctorium,G. obtusum subsp.obtusum andG. labradoricum even exhibit intrapopulation variation. The implications of flavonoid data on the systematics and the astonishing intrapopulation and intraspecific variation are discussed.  相似文献   

3.
Ricinodendron rautanenii provides an easily stored sweet-tasting fruit containing a nut whose seed is rich in fat, protein, and minerals. Its distribution is largely confined to the Zambezian phytogeographical region of Africa, centered on the nutrient- poor Kalahari sands of southeastern Angola and northeastern Namibia. There the estimates of annual nut production range from ca. 250 kg/ha to 800 kg/ ha. In this subhumid summer-rain climate this tree flowers in late spring and the fruits fall in autumn. A significant proportion of the nuts are still edible after having lain on the ground for a year. The nuts were traditionally a staple food for the subregion’s rural populations.  相似文献   

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The primary immune response to the Thy-1.1 antigen was measured by a plaque assay that detected cells producing antibodies lytic for AKR thymocytes. B10.129(6M) mice carrying theH-2 complex of an intermediate responder (129) on a low-responder (B10) background, were low responders. Studies employing different F1 hybrids and segregating generations of 129/J and 6M mice indicated that differences in responsiveness of those two strains depend on alleles at a single locus, loosely linked to theH-2 complex. These results lend further support to the previously advanced concept that the expression of theIr-Thy-1 allcles controlling the response to the Thy-1.1 antigen is influenced by the alleles at theIr-5 locus. In addition, studies employing F1 hybrids produced through matings of 129/J, 6M, C3H.B10 and C57BL/6J mice to a panel of inbred strains suggested that in regard to the responsiveness to the Thy-1.1 antigen, 129/J and 6M mice are phenotypically, and presumably genotypically, similar to C3H.B10 and C57BL/6J mice, respectively.  相似文献   

6.
Two ruderal seam communities, theLactuco-Anthriscetum caucalidis andAhthrisco-Asperugetum procumbentis, are described in Slovakia. Both communities occur on loess in regions of warm and dry climate. Besides the species of theGalio-Alliarietalia, those of theSisymbrietalia andArtemisietalia design the floristical composition of the communities. Numerical classification and ordination techniques were adopted to clarify systematic relations of the communities and show the structure of the revealed clusters. A comparison of the results of the numerical methods and the syntaxonomical table synthesis has been performed and briefly discussed.  相似文献   

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Antisera (B10.129×A)F1 anti-P and (B10×A)F1 anti-B10.P contain antibodies that define, in the PVP hemagglutination test, an antigen originally described as G or H-2.7. Of the independentH-2 haplotypes, the H-2.7 antigen is present inf, j, k, p, ands. In addition, the antisera also contain a weak cytotoxic antibody, distinct from anti-H-2.7. The cytotoxic antibody reacts with antigens controlled by theK orI regions. The hemagglutinating H-2.7 antibody does not have cytotoxic activity. The genetic determinant coding for antigen H-2.7 can be mapped into the chromosomal segment between theS andD regions. The H-2.7 antigen thus serves as a marker for a new region of theH-2 complex. The locus coding for antigen H-2.7 is designatedH-2 G and the correspondingH-2 regionG. The H-2.7 antigen has a tissue distribution distinct from that of the H-2 antigens controlled by theK orD regions. So far it could be detected primarily on erythrocytes.  相似文献   

10.
A new classification is presented of plant communities with predominantPotentilla reptans, in anthropogenic habitats of villages in Western Slovakia, earlier described as thePotentilletum reptantis Eliá? 1974. Species poor communities in drier soils of the roadside and embankments are retained in the associationPotentilletum reptantis Eliá? 1974 emend. Species richer communities in relatively moist ruderal habitats are separated as a new association, thePrunello-Potentilletum reptantis Eliá? 1978.  相似文献   

11.
Maranthes, previously known in the Neotropics only from Panama, has recently been collected in Nicaragua and Costa Rica. Prior to publication of the Chrysobalanaceae of theFlora de Nicaragua, the new combinationMaranthes panamensis (Standl.) Prance & F. White is made and based onCouepia panamensis, previously considered conspecific with the AsiaticM. corymbosa Blume.  相似文献   

12.
Seventeen families with one or two children suffering from congenital adrenal hyperplasia (CAH) were not only typed for their HLA-A,B, and D antigens but also tested biochemically forCAH heterozygosity after ACTH stimulation. The lod score analysis showed a close genetic linkage betweenCAH andHLA, indicating that theC-21-hydroxylase deficiency gene(s) causing CAH in the homozygous deficient state are-located in close proximity to theHLA complex on chromosome 6 with an estimated recombination fraction of 0 to 5%. HLA typing in 21 unrelated CAH patients revealed a statistically significant association to the HLA-B5 antigen with a relative risk value of 5.8. There was a significant correlation (P=0.0025) between theHLA segregation data and theCAH heterozygosity test results in relatives of CAH patients although a few ‘false negative’ results in theCAH heterozygosity test were observed. Thus, the combination of HLA typing and this biochemical test at present provides the most precise approach for detecting CAH carriers in families of CAH patients.  相似文献   

13.
Twenty-five new congenic lines with distinctive BALB/cBy-strain histocompatibility alleles introduced onto the C57BL/6By-strain background by a regimen of backcrossing and tailskin grafting have been established. Twenty-one of the histocompatibility loci represented by these lines are new, while four duplicate theH-1, H-2, H-7, andH-8 loci identified by Snell.  相似文献   

14.
A 3-year study was conducted to determine the effects of mepiquat chloride and N levels on yield and quality of cotton (Gossypium hirsutum L.). Mepiquat chloride (MC) treatments did not significantlyaffect yields; however, cotton lint yields (1980) were 688, 949, 1,011, and 1,045 kg/ha for N rates of 0, 45, 90, and 135 kg/ha, respectively. Nitrogen by MC interactions on yield were not significant for any of the 3 years. MC treatments reduced plant height for all N levels. Plant height averages over all N levels were reduced 15–33% by the addition of MC. The MC treatments significantly increased the percent of Ca and Mg in the cotton leaves on a dry-weight basis. Nitrogen concentrations of the leaves were not affected by MC treatments. Leaf N levels were not significantly affected by N fertilization in 1979, but leaf N levels in 1980 were significantly increased at the 90 kg N/ha rate when compared with the check treatment.  相似文献   

15.
Fluorescence and circular dichroism were used to follow thepH-dependent conformational changes of granulocyte colony stimulating factor (G-CSF). Tryptophan fluorescence of the spectra monitored at 344 nm, or after deconvolution of the emission spectra, at 345 nm, showed a decrease in intensity on going frompH 7 to 4, with a midtransitionpH of 5.8. On the other hand, tyrosine fluorescence measured either by the ratio of intensity at 308 nm to that at 344 nm, or by the fluorescence intensity at 303 nm after deconvolution of the spectra, increased in intensity as thepH was changed from 6 to 2.5, with a midtransitionpH of 4.5. Near UV circular dichroic spectra also showed changes betweenpH 7.5 and 4.5, which correlated with the transition monitored by the tryptophan fluorescence. The guanidine hydrochloride-induced conformational changes of G-CSF at fivepH values from 2.5 to 7.5 were also studied. Circular dichroic and fluorescence spectra revealed minor conformational changes by the addition of 1 or 2 M guanidine HCl at allpH values examined, while the major conformational transition occurred between 2 and 4 M guanidine hydrochloride. The secondary structure of the protein was most stable betweenpH 3.3 and 4.5. The guanidine HCl-induced denaturation of G-CSF involved more than a two-state transition, with detectable intermediate(s) present, and the structure of the intermediate(s) appeared to depend on thepH used. These results are consistent with thepH dependence of the structure described above, and demonstrate the complex conformational properties of G-CSF.  相似文献   

16.
The endogenous levels of gibberellins (GAs) determined by a combined HPLC-bioassay procedure and the formation ofent-kaurene, an immediate GA precursor, in cell-free extracts were studied in relation to seed development inPharbitis nil Choisy cv. Violet. Three biologically active GA fractions were obtained, tentatively identified as GA3, GA5/ GA20, and a GA fraction, possibly GA19 and/or GA44, which all increased in activity during early seed development and subsequently declined during maturation of the seeds. The total endogenous GA level reached its maximum at 19 days after anthesis, just before the seeds had attained their maximum fresh weight at about 23 days after anthesis. Similarly, theent-kaurene synthesizing capacity showed a rapid increase during the period of rapid growth of the seeds, followed by a decline during maturation. A direct relationship between the endogenous GA levels and theent-kaurene synthesizing capacity of a particular tissue was indicated.  相似文献   

17.
Paul A. Fryxell 《Brittonia》1971,23(3):231-237
Dendrosida, here described as new, comprises three taxa:D. batesii Fryxell,D. sharpiana (Miranda) Fryxell ssp.sharpiana, andD. sharpiana ssp.occidentalis Fryxell. The genus is interpreted as a primitive representative of the tribe Malveae, and its relationship to other genera of theAbutilon alliance is discussed. An analysis of mericarp morphology in relation to seed dissemination mechanisms indicates that theAbutilon alliance may be divided into an Abutiloid and a Sidoid group.Dendrosida is included in the latter.  相似文献   

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Mice of three congenic resistant lines differing from C57BL/10 at theH-3, H-13, H-7, andH-8 minor histocompatibility loci were used to immunize, and were immunized with, C57BL/10. Cytotoxic cells which were capable of causing rapid lysis of cells from the immunizing strain were generated at least one-way in all combinations tested. In order for a target to be susceptible to cytolysis, it had to carry both the sameH-2 b haplotype and the same differential minor histocompatibility alleles as the immunizing strain. That is, B10.C(47N) (H-2 b ,H-7 b ) anti-C57BL/10 (H-2 b ,H-7 a ) cytotoxic cells lysed C57BL/10 targets but not B10.BR (H-2 k ,H-7 a ) targets, nor BALB.B (H-2 b ,H-7 b ) targets. Crossreactions in the cytotoxic assay suggest that theH-3, H-13 congenic pair —B10.LP and C57BL/10 —may differ in at least two more minor histocompatibility loci which have not yet been defined. Although 6 x 1066 C57BL/10 lymphoid cells primed B10.D2(57N) (H-8 b ) mice for a secondary in vitro cytotoxic response, a tenfold higher dose apparently made them tolerant. It is concluded that all minor histocompatibility differences can generate cytotoxic T cells which show specificity both for the minor and major histocompatibility alleles.  相似文献   

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