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51.
52.
Summary The results are given of experiments to test wether leaf analyses can be used for diagnostic determinations of deficiency and excess in mineral nutrition of lettuce in soilless culture. re]19760127 相似文献
53.
Amino-terminal sequences of the L, M, and H subunits of reaction centers from the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26 总被引:7,自引:0,他引:7
We have determined the sequence of the 25-28 amino-terminal residues of the three subunits, L, M, and H, of the membrane-bound reaction center protein of the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26. The sequences are as follows: L, H2N-Ala-Leu-Leu-Ser-Phe-Glu-Arg-Lys-Tyr-Arg- Val-Pro-Gly-Gly-Thr-Leu-Val-Gly-Gly-Asn-Leu-Phe-Asp-Phe-(His)-Val-; M, H2N-Ala-Glu-Tyr-Gln-Asn-Ile-Phe-Ser-Gln-Val-Gln-Val-Arg-Gly-Pro-Ala-Asp-Leu-Gly-Met-Thr-Glu-Asp-Val-Asn-Leu-Ala-Asn-; H, H2N-Met-Val-Gly-Val-Thr-Ala-Phe-Gly-Asn-Phe-Asp-Leu-Ala-Ser-Leu-Ala-Ile-Tyr-Ser-Phe-Trp-Ile-Phe-Leu-Ala-X-Leu-Ile-. The H sequence, especially after the aspartyl residue at position 11, is rich in hydrophobic residues, consistent with the possibility that this section of the polypeptide chain is located within the membrane. The L sequence is hydrophilic near the amino terminus and then becomes moderately hydrophobic. The M sequence is of average polarity. 相似文献
54.
Bruce L. Wilson Glenn L. Albright Ph.D. Solomon S. Steiner John L. Andreassi 《Applied psychophysiology and biofeedback》1991,16(1):45-53
In the present study 36 police officers were exposed to a psychological stressor (IQ quiz) and to cold pressor stress while several cardiovascular variables were monitored. Impedance cardiography was used to provide measures of heart rate, stroke volume, cardiac output, myocardial contractility, and total peripheral resistance. In addition, measures of systolic and diastolic blood pressure and peripheral skin temperature were obtained. A multivariate analysis of variance (MANOVA) indicated that significant increases in diastolic and systolic blood pressure during the cold pressor test were mediated by large increases in total peripheral resistance, whereas blood pressure elevation during the IQ quiz were accompanied by significant increases in heart rate and, to a lesser extent, cardiac output. Peripheral skin temperature decreased in response to each stressor. Additional analysis indicated a degree of stimulus specificity for several variables. For example, diastolic blood pressure showed greater increases to cold pressor than quiz, whereas systolic blood pressure increased more with the psychological than the physical stressor. Directional fractionation occurred for both myocardial contractility and cardiac output. 相似文献
55.
Zusammenfassung Im Herbst 1984 schliefen mindestens 50 Hohltauben (Columba oenas), wahrscheinlich aber wesentlich mehr, an drei verschiedenen Stellen auf grobscholligen Sturzäckern der offenen Ackerlandschaft des Marchfeldes östlich von Wien. Bäume verwendeten sie nur als Sammelplatz. Im gleichen Zeitraum war auch ein traditioneller Schlafplatz zusammen mit Türkentauben (Streptopelia decaoto) in einem Wiener Randbezirk (16 km entfernt) benutzt; er lag in einem Gehölz.
Stock Doves (Columba oenas) roosting also in open fields
Summary In autumn 1984, at least 50 — probably many more — Stock Doves roosted in open fields, roughly ploughed, east of Vienna. The nearest trees, 200 metres distant, were used only as perches until darkness approached. Some 16 km distant, another roosting place in trees was shared with Collared Doves (Streptopelia decaocto).相似文献
56.
Subpopulations of different proliferative status are determined during cell-density dependent proliferation of 3T3 cells. From these data the probability of conversion of proliferative to quiescent cells is derived and found to correlate well with published data on binding of growth-inhibiting factors secreted from growth-inhibited cells.Based on material presented at the Symposium Intercellular Communication Stuttgart, September 16–17, 1982 相似文献
57.
Localization of the catalytic subunit of cyclic AMP-dependent. Protein kinase in cultured cells using a specific antibody 总被引:5,自引:2,他引:3
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We developed a specific antibody to the catalytic subunit (C-subunit) of cyclic AMP-dependent protein kinase and used it to localize C- subunit in cultured cells. C-subunit antigen was purified from bovine cardiac muscle and cross-linked to hemocyanin with glutaraldehyde. Immunized goat serum showed a low titer of antibody after boosting; it was enriched 100-fold by affinity chromatography on catalytic subunit- Sepharose. The antibody immunoprecipitated C-subunit from type I and type II holoenzyme and depleted enzymatic activity from solution. At 12.5 nM antigen, 1 microgram antibody immunoprecipitated 10 ng of C- subunit. Immunoprecipitation of 35S-labeled cell extracts and 125I- antibody detection on nitrocellulose paper revealed that the antibody specifically reacts with C-subunit in Chinese hamster ovary (CHO) whole cell extracts. Using indirect immunofluorescence to localize C-subunit, we found a pattern of diffuse staining in the cytoplasm of CHO cells with little or no nuclear staining. A similar distribution of the enzyme was observed in Swiss 3T3 cells, bovine endothelial tracheal cells, human lung fibroblasts and NRK cells. Treatment of CHO cells with 8-bromo-cyclic AMP produced no change in the pattern or intensity of immunofluorescence. We conclude that the majority of C-subunit is localized in cytoplasm and that in cultured fibroblasts exposure to cyclic AMP analogues causes no apparent redistribution of catalytic subunit. 相似文献
58.
Use of formylated yeast initiator Met tRNA to define the NH2-terminal residues of rat preproinsulin and pregrowth hormone 总被引:1,自引:0,他引:1
S J Chan E J Ackerman P S Quinn P B Sigler D F Steiner 《The Journal of biological chemistry》1981,256(7):3271-3275
A method for unambiguously determining the initiator methionine residue and the adjacent NH2-terminal amino acid sequence of cell-free translation products of eukaryotic messenger RNA is described. In this procedure, the NH2 termini of nascent peptides are blocked by incorporating labeled formylmethionine instead of methionine, using yeast initiator tRNA in the wheat germ cell-free system. After immunoprecipitation of the desired product the radiolabeled material is treated with dansyl-Cl to irreversibly block all remaining free amino groups. The material is then deformylated by mild acid hydrolysis and subjected to automated Edman degradation. Only those products that had been synthesized with formylmethionine residues at their NH2-termini can then give rise to labeled phenylthiohydantoin derivatives during degradation. Using this method, we have defined the initiation sites in both rat preproinsulin and pregrowth hormone messenger RNAs. 相似文献
59.
G.J.L. Jones D. Hewitt G.J. Godin W.C. Breckenridge J. Bird M.A. Mishkel G. Steiner J.A. Little 《CMAJ》1980,122(1):37-46
The lipids and lipoproteins — cholesterol (C), triglyceride (TG) and high-density, low-density, very-low-density and sinking pre-β-lipoprotein cholesterol (HDL-C, LDL-C, VLDL-C and SPB-C) — in plasma samples from 1620 fasting white adults and children from the Toronto—Hamilton area were analysed. The mean concentration of HDL-C was about 45 mg/dl in men and about 60 mg/dl in women, and the levels were constant throughout adult life in both sexes. Boys had higher mean HDL-C levels than men, but girls had lower mean HDL-C levels than women. Mean LDL-C levels, like total C levels, increased with age, from about 87 mg/dl in boys to 136 mg/dl in men, and from about 91 mg/dl in girls to 145 mg/dl in women. The mean levels of VLDL-C followed the TG patterns for age and sex, rising from about 7 mg/dl in boys to 26 mg/dl in men, and from about 11 mg/dl in girls to 19 mg/dl in women. SPB-C was detectable visually in 39% of the population and with the aid of densitometry in 54%; the levels were not related to age, sex or oral contraceptive use, and the median level was 3 mg/dl.Prevalence estimates of hyperlipoproteinemia showed that type IV was the most common, and it was found more than three times as often in men as in women. This was in part due to the customary use of plasma TG cut-off points that do not reflect the large difference in TG levels between males and females. Type IIA hyperlipoproteinemia was found in about 2% of the adults and type IIb in a further 1%. Types I, III and V were all rare. The prevalence of types II and IV hyperlipoproteinemia was four times greater in women using oral contraceptives than in nonusers in the same age range. 相似文献
60.
Byung K. Kim Manfred Steiner Mario G. Baldini 《Biochemical and biophysical research communications》1980,97(3):1227-1232
The receptor site for antithrombin III (AT III) was investigated in normal human platelets. [125I] iodinated AT III was utilized as tracer for the binding assay. Equilibrium of AT III binding was reached within 2 min. The binding capacity was pH-dependent with the optimum around pH 7.0. Binding specificity was demonstrated by inhibition of [125I] AT III ligation using an excess amount of non-labeled AT III. The AT III·heparin complex did not supress [125I] AT III binding. Analysis of binding data by Scatchard plot revealed a single class of binding sites with Kd of 3.2 × 10?7 M and binding capacity of 3840 per platelet. 相似文献