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111.
We consider the problem of comparing several nucleic acid sequencesto identify words occurring imperfectly (patterns with no gap)with unusual frequency. Methods for computing, representing,and inspecting interactively the structure of such repeatingmotifs in nucleic acids and more generally any text are described.Multiple sequences are treated as one large concatenate. Ina preprocessing step, a lexical index is created to providerapid string matching for the enumeration of the words matchinga pattern. For given word features (word length, minimal frequency),a sequence profile is displayed. The profile can be inspectedinteractively with on-line algorithms. Applications to the identificationof regulatory elements in DNA regions involved in the controlof gene expression are presented. Our program (‘DNA-Lexemics’)runs on the Macintosh.  相似文献   
112.
Dispersal propensity of green leafhoppers was compared between a tropical species, Nephotettix virescens, and a temperate species, N. cincticeps. The flight ability was measured with tethered flight technique under laboratory conditions (25°C, 16L-8D). The pre-flight period was shorter and the flight duration was longer in N. virescens than in N. cincticeps in both sexes. No significant correlations were found between the flight activity and morphometric characters for either of the two species. The results suggested that dispersal propensity of N. virescens is higher than that of N. cincticeps.  相似文献   
113.
Danforth's short tail (Sd) is a semidominant mutation of the mouse with effects on the skeleton and the urogenital system. In view of its phenotype and its position in the proximal part of Chromosome (Chr) 2, three genes qualified as possible candidates: Pax-8, a paired box-containing gene; Midkine (Mdk), a retinoic acid-responsive gene; and a new locus (Etl-4) identified by enhancer trapping with a lacZ reporter gene which showed expression in the notochord, the mesonephric mesenchyme, and the apical ectodermal ridge. Three different backcrosses involving all three genes in different combinations were set up and analyzed. From our results we conclude that Sd, Etl-4, Pax-8, and Mdk are independent loci, with Etl-4 being the closest genetic marker (1.1±1.4 cM) to the Danforth's short tail (Sd) gene.  相似文献   
114.
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East...  相似文献   
115.
The inhibitory effect of capsaicin on axoplasmic transport in cultured dorsal root ganglion cells was analyzed by video-enhanced contrast microscopy. Capsaicin inhibited particle transports in a dose-dependent manner, irrespective of the diameter of axons. The effect of capsaicin was reversible at low concentrations. Capsaicin affected both the anterograde and retrograde transport. Large organelles were more sensitive to capsaicin than small ones in the retrograde transport. An experiment using calcium-sensitive dye, Fura 2, indicated that capsaicin raised the intraneuronal free calcium concentration preceding the inhibition of the transport. Electron microscopy revealed that microtubules and neurofilaments are disorganized and disoriented by capsaicin. We reached a conclusion that capsaicin inhibits fast axoplasmic transport of both anterograde and retrograde directions in all types of somatosensory neurons in culture by disorganizing intraaxonal cytoskeletal structures, through the elevated intracellular Ca2+ concentration. © 1993 John Wiley & Sons, Inc.  相似文献   
116.
Peptide tag systems are a robust biophysical and biochemical method that is widely used for protein detection and purification. Here, we developed a novel tag system termed “HiP4” (histidine plus four amino acids) whose epitope sequence comprises only seven amino acids (HHHDYDI) that partially overlap with the conventional 6x histidine tag (6xHis-tag). We produced a monoclonal antibody against the HiP4 tag that can be used in multiple immunoassays with high specificity and affinity. Using this system, we developed a tandem affinity purification (TAP) and mass spectrometry (TAP-MS) system for comprehensive protein interactome analysis. The integrated use of nickel bead purification followed by HiP4 tag immunoprecipitation made it possible to reduce nonspecific binding and improve selectivity, leading to the recovery of previously unrecognized proteins that interact with hepatitis B virus X (HBx) protein or TAR DNA-binding protein 43 (TARDBP or TDP-43). Our results indicate that this system may be viable as a simple and powerful tool for TAP-MS that can achieve low background and high selectivity in comprehensive protein–protein interaction analyses.  相似文献   
117.
    
Summary The hybrid produced between a Carbondale haploid strain (-methyl-glucoside rapid fermenter) and a haploid strain (non-fermenter), derived from a hybrid between a homothallic and a heterothallicSaccharomyces, showed an irregular segregation pattern with regard to the fermentation of this sugar.To explain this irregularity, three pairs of alleles,MG 1/mg 1,MG 2/mg 2 andMG 3/mg 3, were assumed to be in quantitative control of the fermetation. Haploid cultures carrying the genotypes (1)mg 1 mg 2 mg 3, (2)MG 1 mg 2 mg 3, (3)mg 1 MG 2 mg 3, (4)mg 1 mg 2 MG 3, (5)MG 1 MG 2 mg 3, (6)MG 1 mg 2 MG 3, (7)mg 1 MG 2 MG 3, and (8)MG 1 MG 2 MG 3, were actually recovered. Strains equipped with: either (1) or (2); either (4) or (6); (3); (5); (7); or (8) are non-fermenters, extremely-slow-fermenters, slow-fermenters, medium-fermenters, semi-rapid-fermenters and rapid-fermenters respectively.The role of these genes in sugar fermentation and the identity or nonidentity of some of these genes with maltose and sucrose genes was discussed.With 2 Figures in the Text  相似文献   
118.
Catalases purified from endosperm glyoxysomes and non-specializedmicrobodies from hypocotyls of castor bean seedlings differedin their specific activity [90–164 and 0.89–4.9kunits (mg protein)–1, respectively] and in their constituentsubunits [two subunits of 54 and 56 kDa for the endosperm enzymeand only one of 56 kDa for the hypocotyl enzyme]. Immunoblotanalysis also showed that particulate fractions from the endospermsand from etiolated and green cotyledons contained two catalasesubunits of 54 and 56 kDa, whereas such fractions from the hypocotylsand roots contained only the 56-kDa subunit. Leaf peroxisomesfrom green leaves had two catalase subunits of around 55 kDaeach. Results of translation in vitro indicated that the 54-and 56-kDa subunits were translated from distinct mRNAs andlevels of both mRNAs increased in the endosperms during germination,prior to increases in levels of catalase proteins. In the hypocotyls,the 56-kDa subunit seemed to be synthesized constitutively. 1Present addresses: YO, Toyota Central Institute, 31-9 Musashizuka,Nagabuchi, Nagakute, Aichi 480-11, Japan  相似文献   
119.
Jasminum odoratissimum is a Madeira and Canary Islands endemic showing classic heterostyly, i.e. with long-styled flowers with anthers at a low level in the corolla tube and short-styled flowers with anthers at a high level in the corolla tube. Short-styled flowers have large pollen, whereas long-styled flowers have small pollen. The two types are present in equal frequencies in the population.  相似文献   
120.
We hypothesized that myocardial contractile function and coronary arterial function are greater after ischemia and reperfusion in high-intensity treadmill-trained vs. sedentary rats. Rats performed 10 x 4-min bouts of treadmill running consisting of 2 min at 13 m/min + 2 min at 45-60 m/min (Etr) or were sedentary (Sed) for 12 wk. Animals then were instrumented to measure left ventricular (LV) contractility in response to three 15-min coronary occlusion (O) and 5-min reperfusion (R) cycles (Isc) or a sham operation (Sham). After the Isc and Sham protocols, hearts were excised and coronary arterial ( approximately 105 microm ID) function was evaluated by using isometric techniques. LV developed pressure, the first derivative of LV pressure at a developed pressure of 40 mmHg, and systolic blood pressure were not different between Etr (n = 14) and Sed (n = 7) rats before or after the Sham protocol. Furthermore, hemodynamic variables were similar in Etr (n = 14) and Sed (n = 13) animals before the Isc protocol and were depressed to the same degree by the three O-R cycles. Therefore, Etr did not alter myocardial contractile function in rats that were (i.e., Isc) or were not (i.e., Sham) exposed to ischemia and reperfusion. Acetylcholine-evoked relaxation (10-8 to 3 x 10-5 M) was greater (P < 0.05) in coronary arteries from Sham-Etr vs. Sham-Sed animals (5 of 8 doses tested) and Isc-Etr vs. Isc-Sed rats (3 of 8 doses tested). Maximal relaxation produced by sodium nitroprusside (10-4 M) was similar among groups. Vasocontractile responses produced by KCl (10-100 mM) and endothelin-1 (10-11-10-4 M) were greater (P < 0.05) in the presence vs. the absence of nitric oxide synthase inhibition (10-6 M NG-monomethyl-l-arginine) in vessels from Sham-Etr but not Sham-Sed rats and from Isc-Etr but not Isc-Sed rats. These findings suggest that Etr-evoked improvements in coronary function are maintained in small arteries even when exposed to ischemia and reperfusion.  相似文献   
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