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391.
392.
The ruthenium(III) complex [(Cp*)RuCl2]2 (Cp*=permethylcyclopentadienyl) catalyzes polymerization of propiolic acid to give a mixture of poly(propiolic acid), [---CH=C(COOH)---]n (1), and cyclic trimers, 1,2,4- and 1,3,5- benzenetricarboxylic acids. GPC analysis shows MN and MW values of the polymer of 4.0 × 103 and 4.3 × 103, respectively. Reaction of propiolic acid in the presence of the Ru(II) complex, (Cp*)RuCI(L) (L=1,5-cyclooctadiene and norbornadiene), gives the cyclic trimers rather than 1. [(Cp*)RuCl2]2 catalyzes polymerization of acetylenedicarboxylic acid and of propargyl alcohol to give the corresponding poly(acetylene) derivatives, [---C(COOH)=C(COOH)---]n (2) and [---CH=C(CH2OH)---]n (3), respectively. Polymerization of ethyl propiolate, 2-butyn-1,4-diol, phenylacetylene and (trimethylsilyl)acetylene using [(Cp*)RuCl2]2 gives the corresponding polymers [---CH=C(COOEt)---]n (4), [---C(CH2OH)=C(CH2OH)---]n (5), [---CH=CPh---]n (6) and [---CH=C(SiMe3)---]n (7) in low yields.  相似文献   
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We studied the effect of deuterium oxide (D2O) on contraction characteristics and ATPase activity of single glycerinated muscle fibers of rabbit psoas. D2O increased the maximum isometric force P0 by about 20%, while the force versus stiffness relation did not change appreciably. The maximum shortening velocity under zero load Vmax did not change appreciably in D2O, so that the force-velocity (P-V) curve was scaled depending on the value of P0. The Mg-ATPase activity of the fibers during generation of steady isometric force P0 was reduced by about 50% in D2O. Based on the Huxley contraction model, these results can be accounted for in terms of D2O-induced changes in the rate constants f1 and g1 for making and breaking actin-myosin linkages in the isometric condition, in such a way that f1/(f1+g1) increases by about 20%, while (f1+g1) remains unchanged. The D2O effect at the molecular level is discussed in connection with biochemical studies on actomyosin ATPase.  相似文献   
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We conducted line route censuses of fungal fruiting bodies from August to September in 2005 and 2006 along ridges and valleys and compared the differences in the encounter rates of fungal fruiting bodies (= fruiting bodies seen per census kilometer) between types of topography and between fungal functional groups (i.e., ectomycorrhizal and saprobic fungi) in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan. We found 251 fungal fruiting bodies (26 families, 50 genera, and 65 species) in total, including 51 bodies from Tricholomataceae, 41 from Russulaceae, 25 from Boletaceae, and 19 from Amanitaceae. The encounter rate of ectomycorrhizal fungi was greater at the ridge route (26.7 unit/km) than at the valley route (8.7 unit/km) and that of saprobic fungi was greater at the valley route (25.0 unit/km) than at the ridge route (12.5 unit/km). In addition, we conducted 7-year intermittent sampling and identified 40 families, 96 genera, and 142 species. The topography-specific emergence pattern of the intermittent sampling method was similar to that of the line census method. The fungal species composition in this study was possibly affected by a topographic gradient for both fungal functional groups through soil moisture, nutrient availability, and host tree distribution.  相似文献   
397.
Cyanobacteria are photoautotrophic organisms capable of oxygen-producingphotosynthesis similar to that in eukaryotic algae and plants,and because of this, they have been used as model organismsfor the study of the mechanism and regulation of oxygen-producingphotosynthesis. To understand the entire genetic system in cyanobacteria,the nucleotide sequence of the entire genome of the unicellularcyanobacterium Synechocystis sp. PCC6803 has been determined.The total length of the circular genome is 3,573,470 bp, witha GC content of 47.7%. A total of 3,168 potential protein codinggenes were assigned. Of these, 145 (4.6%) were identical toreported genes, and 1,259 (39.6%) and 342 (10.8%) showed similarityto reported and hypothetical genes, respectively. The remaining1,422 (45.0%) showed no apparent similarity to any genes registeredin the databases. Classification of the genes by their biologicalfunction and comparison of the gene complement with those ofother organisms have revealed a variety of features of the geneticinformation characteristic of a photoautotrophic organism. Thesequence data, as well as other information on the Synechocystisgenome, is presented in CyanoBase on WWW [http://www.kazusa.or.jp/cyano/]. (Received July 24, 1997; Accepted September 17, 1997)  相似文献   
398.
Clarification of the criteria for managing animal health is essential to increase the reliability of experiments and ensure transparency in animal welfare. For experiments performed in space, there is no consensus on how to care for animals owing to technical issues, launch mass limitation, and human resources. Some biological processes in mammals, such as musculoskeletal or immune processes, are altered in the space environment, and mice in space can be used to simulate morbid states, such as senescence acceleration. Thus, there is a need to establish a novel evaluation method and evaluation criteria to monitor animal health. Here, we report a novel method to evaluate the health of mice in space through a video downlink in a series of space experiments using the Multiple Artificial-gravity Research System (MARS). This method was found to be more useful in evaluating animal health in space than observations and body weight changes of the same live mice following their return to Earth. We also developed criteria to evaluate health status via a video downlink. These criteria, with “Fur condition” and “Respiratory” as key items, provided information on the daily changes in the health status of mice and helped to identify malfunctions at an early stage. Our method and criteria led to the success of our missions, and they will help establish appropriate rules for space experiments in the future.  相似文献   
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400.
Psychogenic fever is one of the most common psychosomatic diseases. In Japan, psychogenic fever has generally been reported to occur in adolescents, with a peak seen at age 13. However, in our department we have encountered many adults with psychogenic fever. Therefore, we investigated all outpatients who visited the Psychosomatic Department of the University of Occupational and Environmental Health between April 2003 and March 2007. Of the 2705 outpatients that were seen, 55 patients (2.0%) were diagnosed with psychogenic fever. The patients ranged in age from 11 to 82 years old, with a mean age of 33.6 ± 17.9 (mean ± SD) years. In addition to the adolescents, many of the patients were in their 20 s and 30 s, and the male:female ratio was 1:2.2. This study suggests that psychogenic fever commonly occurs not only in adolescents but also in adults.  相似文献   
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