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991.
Characterization of a Facultatively Psychrophilic Bacterium, Vibrio rumoiensis sp. nov., That Exhibits High Catalase Activity 总被引:1,自引:0,他引:1
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Isao Yumoto Hideaki Iwata Tomoo Sawabe Keisuke Ueno Nobutoshi Ichise Hidetoshi Matsuyama Hidetoshi Okuyama Kosei Kawasaki 《Applied microbiology》1999,65(1):67-72
A novel facultatively psychrophilic bacterium, strain S-1, which exhibits extraordinarily high catalase activity was isolated from the drain pool of a fish product processing plant that uses H2O2 as a bleaching and microbicidal agent. The catalase activity of the isolate was 1 or 2 orders of magnitude higher than those of Corynebacterium glutamicum, Staphylococcus aureus, Pseudomonas fluorescens, and five other species tested in this study. The strain seemed to possess only one kind of catalase, according to the results of polyacrylamide gel electrophoresis of the cell extract. The optimum temperature for catalase activity was about 30°C, which was about 20°C lower than that for bovine catalase activity. Electron microscopic observation revealed that the surface of the microorganism was covered by blebs. Although the isolate was nonflagellated, its taxonomic position on the basis of physiological and biochemical characteristics and analysis of 16S rRNA sequence and DNA-DNA relatedness data indicated that strain S-1 is a new species belonging to the genus Vibrio. Accordingly, we propose the name Vibrio rumoiensis. The type strain is S-1 (FERM P-14531). 相似文献
992.
Effects of exogenous human heparin-binding epidermal growth factor-like growth factor on DNA synthesis of hepatocytes in normal mouse liver. 总被引:2,自引:0,他引:2
993.
Junko Nagata Ryuichi Masuda Hidetoshi B. Tamate Shin-ichiro Hamasaki Keiji Ochiai Masahiko Asada Shirow Tatsuzawa Kazuki Suda Hiroyuki Tado Michihiro C. Yoshida 《Molecular phylogenetics and evolution》1999,13(3):23
To investigate genetic diversity among populations of the sika deer, Cervus nippon, nucleotide sequences (705–824 bases) of the mitochondrial D-loop regions were determined in animals from 13 localities in the Japanese islands. Phylogenetic trees constructed by the sequences indicated that the Japanese sika deer is separated into two distinct lineages: the northern Japan group (the Hokkaido island and most of the Honshu mainland) and the southern Japan group (a part of the southern Honshu mainland, the Kyushu island, and small islands around the Kyushu island). All sika deer examined in this study shared four to seven units of repetitive sequences (37 to 40 bases each) within the D-loop sequences. The number of tandem repeats was different among the populations, and it was specific to each population. Six or seven repeats occurred in populations of the northern Japan group, while four or five repeats occurred in populations of the southern Japan group. Each repeat unit included several nucleotide substitutions, compared with others, and 26 types were identified from 31 animals. Sequences of the first, second, and third units in arrays were clearly different between the northern and the southern groups. Based on these D-loop data, colonization and separation of the sika deer populations in the Japanese islands were estimated to have occurred less than 0.5 million years before present. Our results provide an invaluable insight into better understanding the evolutionary history, phylogeny, taxonomy, and population genetics of the sika deer. 相似文献
994.
The Bonin (Ogasawara) Islands are oceanic islands located in the northwest Pacific, and have ten native (nine endemic) bee
species, all of which are nonsocial. The European honeybee (Apis mellifera), which was introduced to the islands for apiculture in the 1880s, became naturalized in a few islands shortly after introduction.
To detect the impact of the honeybees upon native bee diversity, we analyzed pollen harvest by honeybees and surveyed the
relative abundance of honeybees and native bees on flowers on several islands. Both hived and feral honeybee colonies were
active throughout the year, harvesting pollen of both native and alien flowers and from both entomophilous and anemophilous
flowers. Honeybees strongly depended on the alien plants, especially during winter to spring when native melittophilous flowers
were rare. From June to November, honeybees exhaustively utilized native flowers, which had originally been utilized and pollinated
by native bees. On Chichi and Haha Islands, where human disturbance of forests has been severe, both native and alien flowers
were dominated by honeybees, and native bees were rare or extinct even in well-conserved forests. In contrast, on Ani Island
and Haha's satellite islands where primary forests were well conserved and honeybees were still uncommon or absent, native
bees remained dominant. These results suggest that competition for nectar and pollen of the native flowers between honeybees
and native bees favors honeybees on the disturbed islands, which are thoroughly invaded by alien nectariferous, sometimes
aggressive, weedy plants.
Received: May 8, 1998 / Accepted: May 6, 1999 相似文献
995.
S. Yoshida T. Tsukiboshi T. Arie H. Shinohara M. Koitabashi S. Tsushima 《Journal of Phytopathology》2007,155(1):38-44
An omnivorous phytopathogenic fungus, Glomerella cingulata, was isolated from rice plants in Japan. We evaluated the effect of the fungus as an inoculum source for anthracnose to other plants. Leaf sheaths of rice plants were monitored in mid‐June and mid‐July for 2 years to evaluate the quantitative inhabitancy of G. cingulata in the fungal community. The pathogenicity of G. cingulata to 20 plant leaves was elucidated. A hygromycin B‐resistant green fluorescent protein (GFP) mutant of the fungus was used to observe fungal infection and development processes on rice plants. Glomerella cingulata was detected on rice sheaths in mid‐June at a low frequency, but was not detected in mid‐July. The fungus has a broad pathogenic spectrum, whereas development of the GFP mutant in tissues of rice plants was limited. Thus, the effect of G. cingulata inhabiting rice plants as a source of inoculum for other crops is likely to be low, although the fungal potential to infect various plants was ascertained. 相似文献
996.
Fresh human urine was found to contain at least three different molecular forms of fibrin-binding urokinase (UK) or its precursor, all of which were absorbed on a fibrin/Celite column at neutral pH, and could be eluted with 0.3-1.0 mol/l NaCl in phosphate buffer, followed by 0.2 mol/l, Arg, 2 mol/l KSCN, and 2 mol/l urea, respectively. The main molecular form isolated revealed a molecular weight (MW) of approximately 100,000 (UK-100), and the minor ones were estimated to have MW of 150,000-200,000 and 45,000. In contrast, commercially obtained UK preparations contained mostly active enzymes with MW of 53,000 and 32,000, respectively, and the remaining high molecular forms represented less than 2.0% of the total amount. Rabbit monospecific antibody (IgG) against UK subcomponent (active heavy chain; H-chain UK) reacted and inhibited the fibrinolytic activity of all the active UK molecules. The UK-100 isolated was relatively stable in solution at neutral pH and resistant to mild reduction, without molecular change. Although the preparation had a very low specific activity (ca. 300 IU/mg protein), both the pyro-Glu-Gly-Arg-pNA amidolytic and plasminogen activating activities could be partially enhanced by the addition of trace amounts of plasmin. In this process, the appearance of two additional active enzymes of MW 53,000 and 32,000 was also confirmed by zymography. 相似文献
997.
A 16-year old girl of short stature, with round face, mental retardation, and Albright's dimple sign was admitted for evaluation of hypocalcemia. Her serum calcium levels were 6.3-8.0 mg/dl, and phosphorus 6.9-7.8 mg/dl. Although a diagnosis of pseudohypoparathyroidism was initially suggested, her serum iPTH concentration was low (0.1 ng/ml). Furthermore, an injection of synthetic human parathyroid hormone (100 U, hPTH (1-34] was followed by a marked increase in urinary excretion of cyclic AMP and phosphorus. This case suggests that a shortened metacarpal is not a reliable guide in distinguishing between idiopathic hypoparathyroidism and pseudohypoparathyroidism and that a standard Ellsworth-Howard test is a prerequisite to differential diagnosis. 相似文献
998.
T Tsushima Y Ohba N Emoto K Shizume Y Imai 《Biochemical and biophysical research communications》1985,133(3):951-957
Transforming growth factor (TGFs) are a family of peptide(s) defined by their ability to induce anchorage-independent growth of non-neoplastic indicator cells in soft agar. We found that acid-ethanol extracts of human anterior pituitary tissues were able to stimulate colony growth of normal rat kidney fibroblasts in soft agar. When subjected to gel-filtration on a column of Bio-Gel P-60 in 1 M acetic acid, the majority of TGF activity eluted in fractions corresponding to an apparent mol wt 15,000. The activity was heat- and acid-stable, but was inactivated by treatment with trypsin and dithiothreitol. Pituitary TGF-like materials did not compete with epidermal growth factor (EGF) for receptor binding and did not require EGF for colony-forming activity. Thus, human pituitary TGF was not like type alpha or type beta TGF. 相似文献
999.
T Yamanouchi T Tsushima M Kasuga F Takaku 《Biochemical and biophysical research communications》1985,129(1):293-299
A human myeloid leukemia cell line (HL-60) produces a peptide or peptides with insulin-like activity which is distinct from insulin or insulin-like growth factors (somatomedins). Factors regulating the production of this peptide (HL-ILP) were explored in the present study. The production of HL-ILP was maximal in the early log phase of cell growth and declined with increasing cell density. Differentiation of HL-60 cells to macrophages, induced by dihydroxyvitamin D3 or phorbol esters, was also associated with a decrease in HL-ILP production. Glucose consumption by the cells in the early log phase was closely related with HL-ILP production, and HL-ILP was found to stimulate glucose consumption by HL-60 cells. Production of HL-ILP was dependent on glucose concentrations in the culture medium and glucose concentrations higher than 1mg/d1 suppressed the release of HL-ILP. These observations are not inconsistent with a hypothesis that HL-ILP is involved in the glucose metabolism of the HL-60 cells that produce this peptide. 相似文献
1000.
It was found that cyanogen bromide (BrCN) treatment of the highly purified human urinary trypsin inhibitors (H-UTI; specific activity 1,897 U/mg protein, and L-UTI; specific activity 1,850 U/mg protein) readily produced new plasmin inhibitors with almost no loss of UTI activity. Five multiple forms of chemically cleaved inhibitors (UTIB-I, UTIB-II, UTIB-III, UTIB-IV and UTIB-V) could be isolated from BrCN-treated L-UTI by isoelectric focusing and gel filtration. These inhibitors were very acid-stable and their isoelectric points (pI) were 4.5, 4.6, 4.9, 5.1 and 6.4, respectively. The molecular weights by SDS-polyacrylamide gel electrophoresis were almost the same at about 23,000 +/- 3,000. Although these inhibitors showed both anti-plasmin and anti-trypsin activities, much higher anti-plasmin/anti-trypsin activities were observed in the cleaved inhibitors than in the parent UTI. They competitively inhibited human plasmin with Ki values of 3.0-4.1 X 10(-8) mol/l (H-D-Val-Leu-Lys-pNA substrate). 相似文献