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11.
Retinoblastoma and the progression of tumor genetics   总被引:10,自引:0,他引:10  
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12.
Thirty-five honey-bee colonies, originally free fromVarroa jacobsoni (Oudemans) were monitored approximately every third week for the presence of the mite during 16 months following an initial introduction of five to eight adultVarroa females in early July. Investigations of hive debris detected the presence ofV. jacobsoni in 22 colonies (63%) within three months of the mite introduction. During the first winter period (October–April), mites were found in the hive debris of 13 colonies (37%). In terms of detectingVarroa during the summer in colonies with sealed brood, investigations of hive debris were more effective than sampling of brood. Brood sampling was more effective than sampling of live bees. In colonies without sealed brood, investigations of hive debris or of live bee samples seemed approximately equally efficient. The highest correlation between sampling methods was found between daily mite downfall and mites per live bee (r=0.81) in colonies with sealed brood. During the winter, investigations of dead bees and hive debris were approximately equally efficient in detectingVarroa.  相似文献   
13.
Biphasic changes in leukocytes induced by strenuous exercise   总被引:1,自引:0,他引:1  
Seven healthy male volunteers participated in short- (STR, 1.7 km), middle- (MTR, 4.8 km) and long- (LTR, 10.5 km) term runs at a speed close to their maximum. A prompt mobilization of white cells, and lymphocytes in particular, appeared following the exercise. The initial increase in the number of lymphocytes was succeeded by a significant decrease [(P less than 0.03) lymphopenial], which on average was 32%-39% of the pre-exercise values in all groups. A close correlation was found between the initial increase in plasma cortisol concentration after exercise and the subsequent lymphopenia. A modest enhancement in the number of granulocytes immediately after the exercise was accompanied by a comprehensive increase in polymorphonuclear (PMN) elastase concentration accounting for 78.6%, SEM 16.3%, 140.7%, SEM 31.8% and 241.3%, SEM 48.1% in the STR, MTR and LTR groups. No correlation was found between granulocyte number and the plasma PMN elastase concentration. A delayed granulocytosis was noted in all subjects, reaching a peak between 2 and 4 h after the exercise. The magnitude of the granulocytosis varied among subjects and peak values of the number of circulating granulocytes were found to be 5.7 x 10(9) cells.l-1, SEM 0.5, 6.7 x 10(9) cells.l-1, SEM 0.6 and 8.8 x 10(9) cells.l-1, SEM 0.5 in STR, MTR and LTR respectively, whereas the mean baseline value was 3.6 x 10(9) cells.l-1, SEM 0.4. The neutrophilic granulocytosis was not accompanied by a corresponding enhancement in PMN elastase concentration. The plasma cortisol concentration reached a peak 30 min after exercise and declined below the control level in 4 h. Neither the initial increase, nor the subsequent decrease in plasma cortisol concentration were found to be essential for the magnitude of the delayed leukocytosis.  相似文献   
14.
Strains from four different DNA relatedness groups of Bacillus circulans showed apparent alginate lyase activity; the activity of three strains examined had mannuronidase specificity. A representative strain of group 4 also produced apparent inducible unsulfated chrondroitin lyase activity.  相似文献   
15.
Deoxyribonucleic acid hybridization among strains of lactobacilli   总被引:1,自引:0,他引:1  
Hybridization of deoxyribonucleic acid (DNA) from Lactobacillus bulgaricus (ATCC 11842) with DNA of L. lactis (ATCC 12315), L. helveticus (ATCC 15009), and L. jugurt (ATCC 521) showed 86.0% reassociation with L. lactis, 4.8% with L. helveticus, and none with L. jugurt.  相似文献   
16.
Pregnancy-associated murine protein-1 (PAMP-1) could not be detected in peripheral blood of female dwarf mice (genotype dw/dw of the DW strain). By contrast the normal size females of the DW strain (genotypes +/+ and +/dw) had PAMP-1 serum levels of 18.9 AU +/- 15.7 AU/ml. Following administration of biosynthetic human growth hormone (hGH) every 2 h for 52 h PAMP-1 was detected in all dwarf females at concentrations of 16.0 AU +/- 3.3 AU/ml. The albumin levels in the circulation of DW females of normal size were significantly higher (P less than 0.05) than those of DW dwarfs, and the hGH administration did not change the serum albumin levels. The present experiment adds weight to the suggestion that the PAMP-1 serum level is regulated by GH.  相似文献   
17.
18.
In laboratory experiments, the bacterial flora of the zooplanktonmicrobial environments seawater, fecal pellets and associatedwith the external and internal surfaces of the copepod Acartiatonsa(Dana) were examined. The bacteria associated with fecal pelletswere dominated by Bacillus spp., Cytophaga/Flavobacterium spp.,Vibrio spp. and Pseudomonas spp. The same genera were foundin the seawater (0.22 7mu;m filtered) in which the pellets wereincubated. The bacteria showed a characteristic growth succession,and the abundance increased several orders of magnitude in theseawater during incubation of the pellets, indicating growthand proliferation based on the disintegrating/degrading fecalpellets. A carbon budget calculation revealed that organic matterfrom degrading fecal pellets could cover the carbon demand forthe growing bacterioplankton. The composition of the bacterialcommunity in the seawater and the fecal pellets also indicateda colonization of the pellets from bacterioplankton. The compositionof the bacteria associated with the copepods showed that bacterialgenera characterized as surface associated were preferentiallyassociated with fecal pellets, animal surfaces and intestines.This suggests a specific intestinal flora in the cultivatedcopepods composed of 103 culturable bacteria per intestine (colony-formingunits, c.f.u.) or 105 bacteria per intestine (acridine orangedirect counts, AODC), possibly colonizing the intestine passivelyduring filtration of algae. The activity of the bacterial communitieswas examined by the numencal ratio c.f.u.:AODC, where 1–19%of the bacteria were found active, with no significant differencebetween microbial environments.  相似文献   
19.
A taxonomic treatment of the genus Ptyssiglottis including Ancylacanthus, Hallieracantha, Oreothyrsus , and Polytrema is given. The phylogeny is briefly dealt with. Leaf morphology, inflorescence morphology and pollen morphology yield important characters. The distribution of selected characters is mapped. The distribution of all species is mapped. Eight new species are published viz. P. campanulata, P. decurrens, P. fusca, P. glandulifera, P. longisepala, P. mucronata, P. pubescens , and P. stamino-difera . Fifteen new combinations are made viz. P. caudata, P. creaghii, P. cuprea, P. cyrtandroides, P. dulcamarioides, P. fastidiosa, P. glabrisepala, P. granulata, P. nigrescens, P. peranthera, P. psychotriifolia, P. pubisepala, P. salicifolia, P. sanguinolenta , and P. undulata .  相似文献   
20.
Two humanized antibody mutants, hLL2HCN1 and hLL2HCN5, engineeredwith CH1 domain-appended carbohydrates (CHOs) were generatedto facilitate site-specific conjugation of radionudides andanti-cancer drugs to antibodies. Such site-specific conjugationmay minimize the incidence of immunoreactlvity perturbationas is often observed with random conjugation. Since the compositionsand structures of CHOs are important in determining the chemistry,efficiency, and extent of conjugation, the sequences of theCH1-appended CHOs were determined by exoglycosidase digestionsand fluorophore-assisted CHO electrophoresis (FACE). The CHOspecies attached at HCN1 and HCN5 sites in hLL2HCN1 and IJLL2HCN5,respectively, were distinct from each other, heterogeneous,and extensively processed. All of these CHOs were corefucosylatedcomplex-type oligosaccharides and contained Gal (galactose)and GlcNAc (N-acetylglucosamine) residues in the outer branches.Some of the outer branches were composed of Gal  相似文献   
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