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31.
Summary The XmnI genotype at the apolipoprotein A-I locus was heterozygous in a boy with partial deletion of the long arm of chromosome 11, del(11)(q23.3qter). The apolipoprotein A-I gene, previously assigned to chromosome region 11q23q24, has been more specifically localized to 11q23 by excluding the region 11q24qter.  相似文献   
32.
The effects of different light regimes on the survival, growth and morphology ofQuercus serrata seedlings were studied in canopies ofMiscanthus sinensis. The seedlings of various ages (0–3 yr) were grown in three light regimes: under a denseM. sinensis canopy (TG plot) receiving 2.5%–8.7% of full sunlight, under a relatively sparse canopy (SG plot) receiving 3.8%–16.1% of light and in an adjacent open site (NG plot). There was a little difference in the survival ofQ. serrata seedlings among the three plots. Height and diameter of stem and total leaf area of the seedlings were significantly lower in the shadier plots. However, the first (bottom) flush of the stem was significantly longer in the TG plot than in the NG and SG plots. Total dry weights of individual 1- and 2-yr-oldQ. serrata seedlings in the TG plot were reduced to about one-twelfth of those in the NG plot. Although the relative proportion in dry weight of each organ did not differ significantly among the plots, leaf area ratio, specific leaf area and stem height per unit dry weight were significantly higher in shadier plots. The leaf area per unit stem height was increased considerably in the sunnier plots.  相似文献   
33.
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was – 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988)  相似文献   
34.
The molybdenum-iron component of nitrogenase (Mo-Fe component)was purified from soybean nodule bacteroids and antibody wasraised against it in rabbits. Antibody raised against the 53kDa polypeptide which was the major protein in the Mo-Fe componentfraction of soybean nitrogenase was confirmed to be specificto the nitrogenase by immunodiffusion and immunotitration. Thenitrogenase from root nodules of Elaeagnus pungens cross-reactedwith the antibody and appeared from the results of the immunodiffusionto be partially identical to soybean nitrogenase. Using the antibody, we examined intracellular localization ofnitrogenase in root nodules of Elaeagnus pungens, in which Frankiais present as a symbiont, by immuno-gold labelling. Thin sectionsof nodules of Elaeagnus pungens were first treated with anti-nitrogenasespecific antibody and then with colloidal gold-protein A asa marker. The gold particles were observed to be concentratedin the vesicles of the endophyte Frankia. This provides strongsupport for the existence E of nitrogenase in the vesicles.Furthermore, our results suggested that nitrogenase localizesin the hyphae of the endophyte Frankia in Elaeagnus pungensnodules. 1Present address: Iwata Experiment Station, Japan Tobacco Inc.,Iwata-gun, Shizuoka 438, Japan. (Received March 9, 1988; Accepted July 28, 1988)  相似文献   
35.
Diverticular disease of the colon was detected in a female Japanese monkey by X-ray examination. The monkey was 15 years old and had been kept under captive conditions for nine years. Lack of appetite and activity, and constipation were observed. The monkey was given fiber-rich vegetables and wild plants, and its appetite and activity then improved. Based on a consideration of various factors, it is suggested that one possible cause of the diverticulosis in this case was a low dietary fiber intake.  相似文献   
36.
Effects of microsite light availability on the growth and survival of transplantedQuercus serrata Thunb. seedlings in aMiscanthus sinensis Anderss. grass canopy were investigated by a “plant's eye view” approach. Diffuse site factors, i.e., the fractional transmissions of diffuse photosynthetic photon flux density, were estimated at 15 cm aboveground in 108 microsites where the seedlings grew. Microsite diffuse site factors were significantly different between surviving and dead seedlings during the experiment period from April to October (F[1,14]=10.9, P<0.01). Relative growth rate of dry weight for individual seedlings positively depended on the diffuse site factors (r2=0.482, P<0.001 in May; r2=0.312, P<0.001 in October). Only 16 seedlings produced their second stem flush within the grass canopy. The ratio of height to dry weight of the second stem flush was significantly higher for the seedlings grew in shady microsites than for those in less shady microsites (r2=0,471, P<0.01 in May). This study suggests that the microsite heterogeneity of light availability is one of the important factors affecting the establishment of tree seedlings in patchy grasslands.  相似文献   
37.
Placental transmission of Pneumocystis carinii in mice was examined in 39 animals obtained by caesarean section from 17 pregnant SCID females experimentally infected with P. carinii. When examined with toluidine blue O, DAPI and immunofluorescent antibody stains, P. carinii was detected in the lungs of infected mothers but not in the lungs of caesarean section-derived neonates even after the neonates were treated with dexamethasone for 8 weeks. However, 13 neonates born to five infected females developed P. carinii pneumonia. These results indicate that P. carinii cannot be transmitted transplacentally in mice.  相似文献   
38.
39.
Summary The catalytic activities of -chymotrypsin, subtilisin Carlsberg, and subtilisin BPN' for hydrolysis of amino acid esters in acetonitrile-water were unusually dependent on the solvent composition. The products obtained as precipitates in high concentrations of acetonitrile were L-amino acids of high optical purities, and effective optical resolution of amino acids was achieved.  相似文献   
40.
Summary A knowledge based system has been shown to be a powerful tool for diagnosing microbial activities during a fermentation process. Knowledge about lactic acid fermentation was collected by an experimental study ofLactobacillus casei. The effects of the inoculum properties and sterilization time on the cultivation were expressed in a form of a fuzzy rule-based knowledge network. The system was able to detect abnormal inoculum or sterilization conditions which caused malfunctions in the cultivations.  相似文献   
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