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81.
Summary The uranaffin reaction in rat anococcygeus muscle, which receives a dual innervation of both adrenergic and non-cholinergic, non-adrenergic nerves was examined. Dense reaction product was observed in the vesicular membranes and/or the cores of some synaptic vesicles in the adrenergic nerve terminals. Occasional vesicles were filled up with dense reaction product. In the prominent population of small clear vesicles, however, no dense reaction product was observed. The number of small granular vesicles in the adrenergic nerve terminals was markedly increased after the administration of 5-hydroxydopamine (5-OHDA). These granular vesicles were moderately stained with uranaffin deposit on the cores but their limiting membranes possessed no uranaffin deposit at all.In the non-adrenergic nerve terminals, on the other hand, uranaffin deposit of variable density was observed on the cores of large granular vesicles but never on their limiting membranes or on the small clear vesicles. There was no change in the axon profiles after the administration of 5-OHDA.The possible occurrence of purines in the cores of large granular vesicles in the non-adrenergic nerves is discussed.  相似文献   
82.
    
Summary Bacillus amyloliquefaciens N produces two restriction enzymes, BamNI and BamNx. Subtilis-phage 1 is strongly restricted by BamNx. We isolated 1 rH, a mutant of phage 1, which overcame the BamNx-restriction by producing inhibitor. This inhibitor inactivated BamNx specifically and reversibly. The inhibitor directly interacted with BamNx and the inactivation might be the result of formation of a binary complex. The inhibitory activity was sensitive to treatment with trypsin. The molecular weight of the inhibitor protein was estimated to be approximately 20,000 daltons by gel filtration.  相似文献   
83.
Fujimura  Taichiro  Kajiwara  Tadahiko 《Hydrobiologia》1990,204(1):143-149
Protoplasts were isolated from thalli of Ulva pertusa using a mixed enzyme solution of 2.0% Cellulase Onozuka R-10, 2.0% Macerozyme R-10, and 2.0% Driselase. Isolated protoplasts regenerated cell walls, developed into thalli, and propagated in large numbers under aeration in the preparative scale-culture system. Typical bioflavor compounds produced from the regenerated plants, as well as from field-collected plants, were found to be long chain aldehydes, which gave a typical seaweed odor. The long chain aldehydes were formed enzymatically from unsaturated fatty acids and released into the culture fluid. A Percoll/mannitol discontinuous density gradient separation of the heterogeneous protoplasts led to a selection of cell lines with high production of bioflavor. The cells that regenerated from protoplasts were immobilized by polymer matrices such as alginate, -carrageenan, agarose, and agar. Living cells entrapped in alginate beads in aerated cultures survived best. However, the beads started to breakdown after two months. The immobilized cells demonstrated a higher bioflavor production than did the cultured cells.  相似文献   
84.
S-Methyl-L-cysteine was actively metabolized in Chinese cabbageand carbon from its methyl group was distributed into both thesoluble and insoluble fractions. The high incorporation of 14Cfrom the methyl group into the insoluble fraction after administeringof S-methyl-L-cysteine-14CH3, and our previous results thatS-methyl-L-cysteine is demethylated to give cysteine, suggestthat S-methyl-L-cysteine might act as a methyl donor in Chinesecabbage. To obtain evidence for this possibility, incorporationof the methyl-14C of S-methyl-L-cysteine into methyl estersof pectic substances was investigated. Most of the 14C incorporatedinto pectic substances was liberated by treatment with dilutealkali and pectin esterase. The results show that S-methyl-L-cysteineacts as a methyl donor to form pectin ester. (Received October 12, 1971; )  相似文献   
85.
Summary An electrophoretic analysis of the microtubule-containing transport channels, known as nutritive tubes, which link the nutritive cells with the chain of developing oocytes in the telotrophic ovarioles of the hemipteran Notonecta glauca, has been carried out. The major polypeptide components resolved have been identified tentatively as -and -tubulin subunits by their comparable electrophoretic mobility to tubulin subunits from purified mammalian brain microtubule protein. Co-migration of some of the minor components with proteins resolved from insect ribosomes (which are the only other components of the nutritive tubes as seen in ultrastructural studies) indicates that these may be ribosomal proteins. Also characterized by electrophoresis were the nutritive cells, which are the source of synthesis of the components transported via the nutritive tubes, and the oocytes, the sites of their accumulation.  相似文献   
86.
A detailed procedure for the separation of diastatic enzymes of molds was established, which was based on their electrophoretic behaviours on a paper strip. For the detection of enzymes, a bioautographical method was newly devised. Comparing the enzymatic images appeared on the paper strip, the authors classified mold enzyme systems into five types.  相似文献   
87.
The biosynthetic pathway of trans-2-hexenal, leaf aldehyde, in isolated chloroplasts of Thea sinensis leaves. was examined using a tracer experiment. A high and specific incorporation of radioactivity into cis-3-hexenal and trans-2-hexenal, was observed when linolenic acid-[U-14C] was incubated with the isolated chloroplasts. Thus, trans-2-hexenal was biosynthesized via cis-3-hexenal from linolenic acid in the chloroplasts.  相似文献   
88.
We systematically studied site-specific deoxyribonucleases in Bacillus strains and detected deoxyribonuclease activities in 20 of 62 strains tested.  相似文献   
89.
Consistent with the previous work by Pestka (Antimicrob. Agents Chemother.5, 255, 1974) on the binding of erythromycin to polyribosomes, we found that erythromycin does not inhibit protein synthesis catalyzed by polyribosomes. This is due to the presence of nascent peptidyl tRNA on the naturally occurring polyribosomes. In a soluble extract from E. coli pretreated to remove the ribosome releasing factor, polyribosomes without nascent polypeptides remain intact and can catalyze protein synthesis in the absence of initiation. In this system erythromycin effectively inhibited protein synthesis. The inhibition by erythromycin was caused by premature release of oligopeptidyl tRNA from polyribosomes.  相似文献   
90.
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