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11.
Phillip Cribb 《Curtis's Botanical Magazine》2005,22(1):22-24
Summary. The golden‐flowered Masdevallia niesseniae Luer from Colombia is described and illustrated from the type collection. 相似文献
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B R Hsu E A Kato W J Raymoure R W Kuhn 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1987,185(3):243-249
A rapid, specific, and sensitive (requiring only 20 fmole of antigen equivalent to 0.007 microliter of serum) radioimmunoassay (RIA) was developed for the measurement of guinea pig corticosteroid-binding globulin (CBG). CBG was purified to homogeneity from guinea pig serum by affinity chromatography and used for immunization, as the standard and as the radiolabeled trace in the RIA. The antiserum to CBG was raised in rabbits. It was judged specific by immunoelectrophoresis and by comparison of RIA values with steroid-binding assay profiles obtained on serum separated on the basis of size and ion-exchange properties. The results of the radioimmunoassays agree with those of a steroid-binding assay run on identical samples. The sensitivity of the assay allows detection of CBG in serial serum samples, other biologic fluids such as milk, and cell culture supernatants. 相似文献
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Two litters of rattlesnakes (Crotalus enyo; n = 6 per litter) were raised in large cages and small plastic boxes, respectively. No significant differences in exploration of a novel environment were observed between the litters, or between either of them and a group of wild-caught C. enyo, suggesting that the common practice of rearing baby snakes in small cages has no debilitating consequences on these measures. In the absence of differences between the litters, the two samples were pooled and additional analyses revealed the existence of reliable individual variation. Experiment 2 compared the two litters and the wild-caught snakes on measures of prey-directed behavior. The two captive-reared litters did not differ, but both exhibited lower levels of strike-induced chemosensory searching than did wild-caught snakes. 相似文献
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All Basidiomycotina screened were sensitive to validamycin A, whereas most Ascomycotina and all Mucorales and Oomycetes were insensitive. Studies with Rhizoctonia cerealis and Fusarium culmorum showed that, in semi-solid culture, the antibiotic caused a decrease in colony radial growth rate and that this was associated with a decrease in mean hyphal extension rate and an increase in hyphal branching. However, the antibiotic did not alter the morphology of R. cerealis grown in liquid culture (shaken or stationary). Validamycin A caused a reduction in the number and viability of conidia produced by F. culmorum. 相似文献
15.
Paternal Imprinting of Inversion Uab(1) Causes Homeotic Transformations in Drosophila 总被引:1,自引:0,他引:1 下载免费PDF全文
Paternal transmission of the bithorax-complex (BX-C) rearrangement, inversion Uab(1), causes a specific dominant gain of function phenotype in most abdominal segments. This represents a case of paternal imprinting since the mutant phenotype will occur only if inversion Uab(1) is paternally transmitted. The transformations in males are toward genital arch tissue. For females the transformations are to tissue found on abdominal segment 7 (Ab7) and to structures normally restricted to the genital disc. Ninety-six percent of transformed areas appear on Ab5 and Ab6 in both sexes and on Ab7 in females, coinciding with the Abd-B domain. Four percent of the transformations occurred on Ab1 through Ab4, coinciding with the abd-A domain. The mutant phenotype can be dramatically enhanced by modifying genes such as the posterior BX-C mutant tuh-3. Expressivity is modulated by maternal effect alleles interacting with tuh-3. A region of function within inversion Uab(1) appears to be programmed during spermatogenesis to function in a legacy dependent manner during embryogenesis. 相似文献
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Seed morphology was studied in 15 species of four subgenera ofJuncus occurring in Kansas, to determine if seeds provide traits useful in assessing systematic relations within the genus. In this study seed size and shape were of limited value, while surface ornamentation of the hard inner seed coat provided encouraging results. SubgenusPoiophylli showed little variation in surface ornamentation among taxa; similar ornamentation was observed in subgenusGenuini. SubgeneraGraminifolii andSeptati were separately distinct with the taxa in theSeptati forming a continuum of variation. 相似文献
18.
Z Hubálek V Cerny T Mittermayer J Kilík J Halouzka Z Juricová I Kuhn V Bárdos 《Journal of hygiene, epidemiology, microbiology, and immunology》1986,30(1):87-98
The serosurveys conducted in the Silica plateau area of the Slovak karst region revealed the presence of specific neutralizing antibody against tick-borne encephalitis (TBE) virus in 18% of local inhabitants (33 examined, mostly goats and sheep farmers), 54% of goats (26 examined), 18% of sheep (120 examined) and 13% of cattle (60 examined), against Lipovník (LIP) virus in 30% of inhabitants, 88% of goats, 55% of sheep and 45% of cattle, and against Bhanja (BHA) virus in 27% of inhabitants, 46% of goats, 29% of sheep and 23% of cattle. The results of hemagglutination-inhibition tests with TBE and BHA antigens were analogous. A detailed analysis of these serologic data points to a recent enhancement of the circulation of LIP and BHA viruses and to a very low TBE virus activity in this natural focus of arboviral infections. The immunological surveys of the 32 former "Roznava disease" patients, conducted 25 years after an extensive epidemic of a TBE virus infection that originated in Roznava in 1951, revealed the presence of neutralizing (and also hemagglutination-inhibiting) antibodies against TBE virus in as many as 78% of cases. Antibodies against LIP and BHA viruses were also detectable in the sera of 16% and 9%, respectively, of these individuals. Populations of the ectoparasites examined for the presence of arbovirus comprised 231 Ixodes ricinus, 806 Dermacentor marginatus and 204 Haemaphysalis punctata ticks and 117 specimens of the louse-flies Melophagus ovinus. Two strains of arbivirus that were antigenically related to Lipovník and Tribec viruses belonging to a group of Kemerovo viruses were isolated from male and female I. ricinus ticks collected from cattle. 相似文献
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