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Diapause pupae of the swallowtail butterfly Papilio xuthus L. exhibit diapause-green, orange and brownish-orange color polymorphism. Development of orange pupae involves a neuroendocrine factor inducing orange pupa (Orange-Pupa-Inducing Factor, OPIF), which is secreted from the head-thoracic region during late pharate pupal stages, in particular from the ganglia of short-day animals located posteriorly from the second thoracic ganglion2 (TG2). This report describes certain properties of OPIF using bioassays involving ligated abdomens of short-day pharate pupae. Localization of OPIF in the central nervous system of short-day larvae indicated that it was present predominantly in TG2, thoracic ganglion3 (TG3) and abdominal ganglion1 (AG1) complexes. OPIF activity in TG(2,3)-AG1 complexes was over two times higher than in the more posteriorely located ganglia. The developmental profile of OPIF in last instar short-day larvae revealed that OPIF activity in larval ganglia posterior to TG2 became gradually higher as larval growth proceeded, suggesting that OPIF might be accumulated in TG(2,3)-AG(1-7) complexes as larvae prepare for pupal molting. Furthermore, ligated abdomens of short-day larvae developed into pupae of an orange type when a 2% NaCl extract containing OPIF prepared from TG(2,3)-AG(1-7) complexes of long-day larvae was injected into ligated abdomens of short-day pharate pupae, indicating that OPIF is also present in long-day larvae. Additionally, a biochemical investigation using gel filtration chromatography showed that the molecular weight of OPIF was about 10 kDa.  相似文献   
84.
In order to corroborate the regulatory role of Ca++-calmodulin system in the steroidogenic response to adrenocorticotropic hormone (ACTH), the effects of calmodulin inhibitors (chlorpromazine, trifluoperazine, and W-7) on cortisol production and cellular cholesterol ester hydrolysis induced by ACTH in bovine adrenocortical cells were examined. Three calmodulin inhibitors diminished not only the cholesterol ester hydrolysis and cortisol production induced by ACTH in the presence of Ca++, but also inhibited the Ca++-induced hydrolysis and cortisol production in the absence of ACTH. Neither cortisol production in crude mitochondrial fraction nor the ACTH-induced Ca++-influx was affected by chlorpromazine. These results indicate that Ca++f-calmodulin system plays a significant regulatory role in the supply of free cholesterol to the adrenal mitochondria in the steroidogenic response to ACTH.  相似文献   
85.
Ichthyological Research - A new snailfish, Careproctus shigemii, is described on the basis of three specimens collected in the southern Sea of Okhotsk, off Hokkaido, Japan. The new species has...  相似文献   
86.
Galectins, a family of animal lectins, are involved not only in development and differentiation but also in immunoregulation and host–pathogen interactions. Galectin-3 interacts with lipopolysaccharides in gram-negative bacteria such as Escherichia coli, Salmonella minnesota and Pseudomonas aeruginosa . The present study investigated whether galectin-3 inhibited the cytokine-inducing activity of periodontopathic bacterial lipopolysaccharides using splenocytes derived from mice of different ages. Lipopolysaccharides were extracted from Aggregatibacter actinomycetemcomitans Y4 and Porphyromonas gingivalis ATCC 33277, and then purified. Enzyme-linked immunosorbent assay (ELISA) analysis revealed that galectin-3 adhered to A. actinomycetemcomitans lipopolysaccharides, but not to the lipopolysaccharides of P. gingivalis . Splenocytes were prepared from 1- or 7-month-old C57BL/6 mice. Either A. actinomycetemcomitans lipopolysaccharides (200 ng mL−1) alone or lipopolysaccharides and murine galectin-3 (10 μg mL−1) were added to culture solutions, and the release of interleukin-6 (IL-6) and interferon-γ (IFNγ) from splenocytes was measured by ELISA after a 17-h incubation. In all mice tested, A. actinomycetemcomitans lipopolysaccharide stimulation significantly increased the production of IL-6 and IFNγ ( P <0.01). Murine galectin-3 suppressed lipopolysaccharide-induced cytokine production in the splenocytes of the 1-month-old mice ( P <0.02 for IL-6; P <0.05 for IFNγ), but not in the splenocytes of the 7-month-old mice. This suggests that responses change with age.  相似文献   
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Periodic limb movements during sleep (PLMS) are identified as a common finding in patients with restless legs syndrome (RLS). Although PLMS are observed in more than 80% of RLS patients in Western countries, little is known about Asian RLS patients and no data are available about Japanese patients. This cross-sectional study aimed to investigate ethnic differences in clinical information and polysomnographic variables including PLMS between Austrian and Japanese RLS patient undergoing nocturnal polysomnography (n-PSG). One hundred Austrian and 139 Japanese consecutive patients diagnosed with RLS who underwent n-PSG were included [Austrian 54.5 ± 13.6 years, 40 females (40%); Japanese 50.2 ± 18.9 years, 88 females (63.3%)]. Medical records and n-PSG data were reviewed retrospectively. Epidemiological, clinical and n-PSG variables were compared between the two groups. Rate of patients with PLMS ≥ 5/h and those with PLMS ≥ 15/h were higher in Austrian than in Japanese RLS patients (80.0 vs. 56.1%, P < 0.001; 55.0 vs. 41.7%, P = 0.043). Accordingly, Japanese RLS patients showed lower PLMS index than Austrian patients (21.3 vs. 33.6/h, P = 0.008). Japanese RLS patients showed higher female predominance, lower BMI, lower systolic/diastolic blood pressure, lower ferritin level and higher International restless legs syndrome severity scale than Austrian patients. None of these variables were associated with PLMS in both groups. Japanese RLS patients showed significantly lower comorbidity rate and lower indices of PLMS compared to Austrian RLS patients. This cross-sectional study on ethnic differences in PLMS in patients with RLS may provide a bridge to a future genetic comparative study between European and Asian RLS patients.

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89.
Because of the illegal use of highly toxic ricin from the castor-oil plant, Ricinus communis, in bioterrorism and suspected white powder cases, anti-terrorism measures for the toxin are urgently required. Here we demonstrate a facile and sensitive detection method using synthetic analogues of beta-lactosyl- and beta-d-galactosyl ceramides as the ligands based on the fact that ricin binds cell-surface oligosaccharides. Sugar-probes having lipoic acids as anchor functions were synthesized via either a chemical or chemoenzymatic way and were immobilized on the sensor chips by a self-assembled monolayer technique. Surface plasmon resonance (SPR) analysis using these carbohydrate probes allowed us to detect the toxin in a highly sensitive and facile manner (10 pg/mL, 5 min), being the best benchmark as a method for detecting the toxin. In addition, a visual monitoring method was developed, in which sugar-coated Au nanoparticles were utilized for discriminating ricin from other proteins in a facile manner, taking 10-30 min for judgment.  相似文献   
90.
Spectroscopic properties, amino acid sequence, electron transfer kinetics, and crystal structures of the oxidized (at 1.7 A resolution) and reduced form (at 1.8 A resolution) of a novel plastocyanin from the fern Dryopteris crassirhizoma are presented. Kinetic studies show that the reduced form of Dryopteris plastocyanin remains redox-active at low pH, under conditions where the oxidation of the reduced form of other plastocyanins is inhibited by the protonation of a solvent-exposed active site residue, His87 (equivalent to His90 in Dryopteris plastocyanin). The x-ray crystal structure analysis of Dryopteris plastocyanin reveals pi-pi stacking between Phe12 and His90, suggesting that the active site is uniquely protected against inactivation. Like higher plant plastocyanins, Dryopteris plastocyanin has an acidic patch, but this patch is located closer to the solvent-exposed active site His residue, and the total number of acidic residues is smaller. In the reactions of Dryopteris plastocyanin with inorganic redox reagents, the acidic patch (the "remote" site) and the hydrophobic patch surrounding His90 (the "adjacent" site) are equally efficient for electron transfer. These results indicate the significance of the lack of protonation at the active site of Dryopteris plastocyanin, the equivalence of the two electron transfer sites in this protein, and a possibility of obtaining a novel insight into the photosynthetic electron transfer system of the first vascular plant fern, including its molecular evolutionary aspects. This is the first report on the characterization of plastocyanin and the first three-dimensional protein structure from fern plant.  相似文献   
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