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101.
102.
Russell G. Snell Leslie M. Thompson Danilo A. Tagle Tracey L. Holloway Glenn Barnes Helen G. Harley Lodewijk A. Sandkuijl Marcy E. MacDonald Francis S. Collins James F. Gusella Peter S. Harper Duncan J. Shaw 《American journal of human genetics》1992,51(2):357-362
We report both a recombination event that places the Huntington disease gene proximal to the marker D4S98 and an extended linkage-disequilibrium study that uses this marker and confirms the existence of disequilibrium between it and the HD locus. We also report the cloning of other sequences in the region around D4S98, including a new polymorphic marker R10 and conserved sequences that identify a gene in the region of interest. 相似文献
103.
The effect of iron on anaerobic digestion 总被引:1,自引:0,他引:1
Summary The ability of methanogenic bacteria to adapt to high concentrations of iron was investigated using a 9l Upflow Anaerobic Sludge Blanket (UASB) reactor fed semi-continuously with a synthetic waste containing glucose as the organic carbon source. It was found that an iron concentration of up to 5 650 mg/l, which is well in excess of previously reported toxicity levels, had no inhibitory effects on anaerobic digestion, with the exception of a decrease in biogas production. The iron precipitated out and accumulated in the sludge bed of the digester, resulting in very low concentrations of iron in the digester effluent. 相似文献
104.
A procedure was established for the induction of regenerable calli from immature inflorescence segments of high-tannin cultivars of sorghum (Sorghum bicolor (L.) Moench). Murashige & Skoog's medium with several components altered was utilized for inducing, maintaining, and regenerating the cultures. Embryogenic calli formed at a frequency of 8–70% depending on the genotype. During a ten-month period, 3600 plants were regenerated from eight genotypes tested. Among the developmental stages of immature inflorescence tested (from differentiation of secondary branch primordia to floret formation) no critical differences were found in potential for callusing, embryogenesis or regeneration. Genotypic differences were observed in pigment production, embryogenic callus formation, shoot differentiation, and in maintenance of regeneration capacity.Abbreviations 2,4-D
dichlorophenoxyacetic acid
This is Journal Paper Number 11972 from the Purdue University Agricultural Experiment Station 相似文献
105.
Timothy K. Hayes Larry L. Keeley 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,160(2):187-194
Summary Several members of the adipokinetic/hyperglycemic neurohormone family from several different invertebrate species have been prepared by solid-phase peptide synthesis and assayed by a modified in vivo hyperglycemic bioassay in Blaberus discoidalis cockroaches. The hypertrehalosemic hormone (HrTH) is the endogenous hypertrehalosemic factor for B. discoidalis and was the most potent peptide in the assay. The more divergent the sequence of a family member from Blaberus HrTH, the less potent was the bioanalog. Manduca adipokinetic hormone is the most divergent peptide of the family and was totally inactive in the bioassay. Locusta adipokinetic hormone I had reduced maximum activity in the assay, which suggests that Ser5 is an important residue for the transduction of the hyperglycemic response. The direct relation between bioanalog similarity to Blaberus HrTH sequence and potency suggests that the hormone and target cell receptor for HrTH have evolved to maintain an optimal fit.Abbreviations
AKH
adipokinetic hormone
-
HrGH
hyperglycemic hormone
-
HrTH
hypertrehalosemic hormone
-
RPCH
red pigmentconcentrating hormone
- CAH
cardioacceleratory hormone. Hormone abbreviations are according to the convention of Gäde and Raina (1989) except that the genus names are not abbreviated 相似文献
106.
Grant St. Julian Rodney J. Bothast Larry H. Krull 《Journal of industrial microbiology & biotechnology》1990,5(6):391-394
Summary By succesive recycling of the thin stillage in mashing and fermenting fresh corn, the glycerol content in each fermentation increased by about 0.4% and accumulated to a high of 2.1% in the beer of the fifth recycle. Glycerol concentration declined after the fifth recycle. The original fermentation contained 0.8% glycerol.Presented in part at the Society for Industrial Microbiology Annual Meeting, August 7–12, 1988, Chicago, IL.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned. 相似文献
107.
Laboratory microcosms were used to: i) measure the effects of soil moisture on survival of Steinernema riobravis and ii) investigate the suitability of using microcosms to study motility and survival of these nematodes. Nematodes recovered from soil contained in petri dishes declined by more than 95% during 7 days, whereas nematodes recovered from the inner surfaces of dishes increased 35-fold. After 7 days in dishes, >20 times as many nematodes were recovered from dish surfaces than from soil. Nematodes exhibited a negative geotropism; greater numbers of nematodes were recovered from the lid surfaces than from the surfaces of dishes. Survivorship of nematodes in soil in plastic centrifuge tubes was somewhat greater than in petri dishes, and fewer nematodes ascended above the soil line in tubes than dishes. Downward migration of nematodes was inversely related to soil column diameter, possibly due to relatively unimpeded movement along container surfaces. An assay was developed by which nematodes were rinsed from the inner surfaces of centrifuge tubes into the soil. The resulting slurry was then processed on Baermann trays to recover motile nematodes. Nematode survival in soil in centrifuge tubes was higher at soil moistures between 2-4% than at lower (0.5-1.0%) and higher (4.0-12.0%) moisture levels. Survival of S. riobravis may be enhanced by quiescence induced by moisture deficits. 相似文献
108.
Stimulation of in vitro shoot proliferation from nodal explants of cassava by thidiazuron, benzyladenine and gibberellic acid 总被引:2,自引:0,他引:2
Basdeo Bhagwat Luiz G. F. Vieiral Larry R. Erickson 《Plant Cell, Tissue and Organ Culture》1996,46(1):1-7
Multiple shoots were produced from nodal explants of cassava (Manihot esculenta Crantz) by a two-step procedure: a 6- to 8-day exposure to 0.11–0.22 µM thidiazuron (TDZ) in liquid Murashige and Skoog (MS) medium followed by culture on agar-solidified MS medium supplemented with 2.2 µM 6-benzyladenine (BA) and 1.6 M gibberellic acid (GA3). TDZ caused the nodal explants to expand and this expansion (growth) continued during culture with BA and GA3. From this expanded explant, clusters of buds and fasciated stems developed continuously and these gave rise to shoots. The shoot proliferation process was open-ended, yielding an average of 31.5 shoots per nodal explant after 10 weeks of culture with genotype CG 1–56. A positive response was also obtained from seven other genotypes evaluated with this protocol.Abbreviations BA
6-benzyladenine
- BM
basal medium
- DPU
1,3-diphenylurea
- GA3
gibberellie acid
- 2iP
isopentenyladenine
- MSM
multiple shoot medium
- NAA
1-naphthaleneacetic acid
- PGR
plant growth regulator
- TDZ
thidiazuron
- Z
zeatin 相似文献
109.
Induction of leaf senescence in Arabidopsis thaliana by long days through a light-dosage effect 总被引:2,自引:0,他引:2
Larry D. Nooden Jennifer W. Hillsberg Michael J. Schneider 《Physiologia plantarum》1996,96(3):491-495
Given the influence of photoperiod on reproductive development and whole-plant senescence in monocarpic plants, one would suspect that leaf senescence in these plants might be under photoperiodic control. In Arabidopsis thaliana , which is monocarpic and also a nonobligate long-day (LD) plant, LDs (16 h, 300 μmol m−2 s−1 ) caused leaves to die earlier than did short days (SDs, 10 h). Since leaf longevity was not paralleled by the reproductive development in the present study, the reproductive structures did not seem to be the primary controls of leaf senescence. The LD effect appeared to depend on the amount of light rather than on day length, for leaves given LDs at reduced light intensity (180 μmol m−2 s−1 ) lived longer than those in LDs with full light. In addition, the higher light intensity promoted chlorophyll loss and anthocyanin accumulation in LDs. Thus, senescence of these leaves seems to be governed by light dosage rather than photoperiod. Light may play a natural role in promoting the senescence of A. thaliana leaves. 相似文献
110.