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11.
文中简述了中欧的林业发展史,特别对德国森林培育的现状和存在的问题进行了比较详细的分析。根据德国森林培育的历史和经验,提出了对中国林业建设的几点启示。 相似文献
12.
Müller Ulrich Ringhofer Andreas Brandner Reinhard Schickhofer Gerhard 《Wood Science and Technology》2015,49(6):1123-1136
Wood Science and Technology - Several studies have dealt with the problem of how to measure the shear modulus of small clear wood specimens, avoiding bias from normal compression, bending, tension... 相似文献
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Dr. Jürgen Schultze-Motel Dr. Reinhard Fritsch Dr. Karl Hammer Dr. Peter Hanelt Dr. Joachim Kruse Dr. Helga I. Maass Dr. Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1982,30(2):273-291
Summary Important papers on taxonomy and evolution of cultivated plants published in 1980 and 1981 were compiled and briefly discussed.
Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet. 相似文献
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1980/1981
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1980 und 1981 wurden zusammengestellt und kurz kommentiert.
: 1980–1981 .
, 1980 1981 . .
Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet. 相似文献
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Jürgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Helga I. Maass Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1990,38(3):417-434
Summary Important papers on taxonomy and evolution of cultivated plants published in 1988 and 1989 were compiled and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1988/1989
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1988 und 1989 wurden zusammengestellt und kurz kommentiert.
: 1988–1989
, 1988 1989 . .相似文献
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Rudolf Hofer Reinhard Lackner Joachim Kargl Bertha Thaler Danilo Tait Leopoldo Bonetti Raffaele Vistocco Giovanna Flaim 《Water, air, and soil pollution》2001,125(1):189-200
Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification. 相似文献
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Estrogenic activity in white and red wine extracts 总被引:8,自引:0,他引:8
Klinge CM Risinger KE Watts MB Beck V Eder R Jungbauer A 《Journal of agricultural and food chemistry》2003,51(7):1850-1857
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Neurotransmitter release is triggered by calcium ions and depends critically on the correct function of three types of SNARE [soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP) receptor] proteins. With use of the large calyx of Held presynaptic terminal from rats, we found that cleavage of different SNARE proteins by clostridial neurotoxins caused distinct kinetic changes in neurotransmitter release. When elevating calcium ion concentration directly at the presynaptic terminal with the use of caged calcium, cleavage of SNAP-25 by botulinum toxin A (BoNT/A) produced a strong reduction in the calcium sensitivity for release, whereas cleavage of syntaxin using BoNT/C1 and synaptobrevin using tetanus toxin (TeNT) produced an all-or-nothing block without changing the kinetics of remaining vesicles. When stimulating release by calcium influx through channels, a difference between BoNT/C1 and TeNT emerged, which suggests that cleavage of synaptobrevin modifies the coupling between channels and release-competent vesicles. 相似文献
20.
Reinhard A. Hirt Alexandra Galler Sarina Shibly Andrea Bilek 《Veterinary journal (London, England : 1997)》2011,187(1):54-59
Airway hyperresponsiveness is a key feature of human asthma and chronic bronchitis and response to the indirectly acting agonist adenosine 5′-monophosphate (AMP) is thought to reflect underlying airway inflammation. To examine whether airway responsiveness testing (ART) with AMP may be used to differentiate healthy cats from those with asthma (FA) and chronic bronchitis (CB), 24 cats (9 FA, 6 CB, 9 controls) underwent ART with AMP at concentrations of 0.1, 1, 10, 100 and 500 mg/mL using barometric whole body plethysmography.The defined endpoint of ART, an increase in enhanced pause (Penh) exceeding 300% of the post-saline value (baseline), was reached in 9/15 patients (7 FA, 2 CB), but in none of the controls. Mean Penh (±SD) at baseline (BL) was 0.49 ± 0.16 for cases, and 0.54 ± 0.16 for controls, and was significantly increased after AMP challenge in clinical cases (2.62 ± 2.20), but not in controls (0.63 ± 0.30, P < 0.05). After separating responder (R) and non-responder (NR) cases, a more pronounced difference after challenge was found (R: 3.96 ± 1.84, NR: 0.6 ± 0.21, P < 0.001). The provocative concentration of the agonist that increased Penh to 300% of BL (PC Penh 300) in R cases was 52.98 ± 48.04 mg/mL AMP. Age had no influence on the responder status or PC Penh 300. It was concluded that AMP challenge may offer a new method for the identification of cats with lower inflammatory airway disease, and possibly for monitoring disease progression or response to therapy. 相似文献