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71.
Patients who undergo surgical extirpation of a primary liver carcinoma followed by radiotherapy and chemotherapy leading to complete remission are nevertheless known to develop cancerous metastases 3–10 years later. We retrospectively examined the blood sera collected over 8 years from 30 patients who developed bone metastases after the complete remission of liver cancer to identify serum proteins showing differential expression compared to patients without remission. We detected a novel RGD (Arg-Gly-Asp)-containing peptide derived from the C-terminal portion of fibrinogen in the sera of metastatic patients that appeared to control the EMT (epithelial-mesenchymal transition) of cancer cells, in a process associated with miR-199a-3p. The RGD peptide enhanced new blood vessel growth and increased vascular endothelial growth factor levels when introduced into fertilized chicken eggs. The purpose of this study was to enable early detection of metastatic cancer cells using the novel RGD peptide as a biomarker, and thereby develop new drugs for the treatment of metastatic cancer.  相似文献   
72.
Partial hydrolysis of a larch arabino(4-O-methylglucurono)xylan afforded two series of oligouronides composed of 4-O-methyl- d-glucuronic acid and d-xylose residues. The first series included aldouronic acids up to the aldopentaouronic acid. Methylation analysis indicated that the aldopentao- and aldotetrao-uronic acids were mixtures of isomers. One aldotetraouronic acid was isolated and identified as O-β-d-Xylp-(1 → 4)-O-β-d-Xylp-(1 → 4)-O-(4-O-Me-α-d-GlcAp)-(1 → 2)-d-Xyl. The two isomeric aldotriouronic acids were separated from each other. The acids of the second series, which were composed of two uronic acids and 2-4 d-xylose residues, were identified as follows: O-β-d-Xylp-(1 → 4)-O-(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-O(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-d-Xyl, O-(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-O-(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-O-β-d -Xylp-(1 → 4)-D-Xyl, O-(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-O-(4-O-Mec-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-D-Xyl, and O-(4-O-Me-α-d-GlcAp)-(1 → 2)-O-β-d-Xylp-(1 → 4)-O-(4-O-Me-α-d-GlcAp)-(1 → 2)-D-Xyl. The first three compounds were new acidic oligosaccharides. The 4-O-methyl-d-glucuronic acid in the second series was present in a larger proportion than in the first series, indicating that a large proportion of the uronic acid side-chains were located on two contiguous D-xylose residues in the backbone of the softwood xylan.  相似文献   
73.

Objective

Bromocriptine mesylate (BRC), a dopamine D2 receptor agonist has been shown to confer neuroprotection, sustained motor function and slowed disease progression in mouse models of amyotrophic lateral sclerosis (ALS) Here we report a first in human trial in ALS.

Design

A multicenter, Riluzole add-on, randomized, double-blind, placebo controlled 102-week extension BRC clinical trial.

Methods

The trial was conducted between January 2009 and March 2012 on 36 Japanese ALS patients. A 12-week treatment with Riluzole observational period was followed by combined treatment (Riluzole + BRC; n = 29 or Riluzole + placebo; n = 7). The dosing commenced at 1.25 mg/day increasing in steps at two weeks intervals to a maximum of 15 mg/day. The efficacy of BRC was evaluated by comparing BRC and placebo groups upon completion of stepwise dosing at 14 weeks 2 points (1st endpoint) and upon completion or discontinuation of the study (2nd endpoint) of the dosing.

Results

Statistics analyses revealed a marginal BRC treatment efficacy with P≦20%to placebo by 1st and 2nd endpoint analysis. In the 1st endpoint analysis, BRC group was significantly effective on the scores of ALSAQ40-communicaton (P = 1.2%), eating and drinking (P = 2.2%), ALSFRS-R total (P = 17.6%), grip strength (P = 19.8%) compared to the placebo group. In the 2nd endpoint analysis, differences between the scores of Limb Norris Scale (P = 18.3%), ALSAQ40-communication (P = 11.9%), eating and drinking (P = 13.6%), and neck forward-bent test (P = 15.4%) of BRC group were detected between the two groups. There was no significant difference between the treatment groups for adverse events or serious drug reactions incidence.

Conclusions

BRC sustains motoneuronal function at least in part through BRC treatment. Further analysis involving a Phase 2b or 3 clinical trial is required but BRC currently shows promise for ALS treatment.

Trial Registration

UMIN Clinical Trials UMIN000008527  相似文献   
74.
In the presence of ferrous ion, ADP, and an NADPH-generating system, [4-14C]pregnenolone was oxidized by bovine liver microsomes to its α-epoxide (5,6α-epoxy-3β-hydroxy-5α-pregnan-20-one), β-epoxide (5,6β-epoxy-3β-hydroxy-5β-pregnan-20-one), trihydroxypregnanone (3β,5,6β-trihydroxy-5β-pregnan-20-one) which were separated, isolated on an octadecylsilicone column in 70% aq. methanol by high performance liquid chromatography, identified with respective synthetic specimens by gas-liquid chromatography-mass spectrometry. The microsomal Δ5-oxidation products of pregnenolone were detected in trace yield either when EDTA was added to the incubation mixture or when ferrous ion was omitted from the mixture. The microsomal oxidation system generated malondialdehyde significantly. It, however, was retarded to a negligible extent either by the addition of EDTA or by the omission of ferrous ion. Therefore, the microsomal formation of the significant yields of Δ5-oxygenated pregnenolones was reasonably attributed to a reaction linked to microsomal lipid peroxidation. The ratio of pregnenolone α- to β-epoxides formed was 1:3. A comparable study carried out under the same conditions by using [4-14C]cholesterol as the substrate resulted in the similar Δ5-epoxidation with concomitant formation of cholestane-3β,5α,6β-triol; cholesterol α- and β-epoxides formed were in the ratio 1:4.Both pregnenolone α- and β-epoxides were hydrolyzed by the microsomes to trihydroxypregnanone as the sole metabolite at a relative rate of 0.6:1. A similar relative value was also obtained in the microsomal hydrolysis of cholesterol α- and β-epoxides to the cholestanetriol.  相似文献   
75.
To examine the disease state of cold constitution, physiological measurements of the foot were conducted by investigating thermal sensations under an environmental condition of 25 degrees C-26 degrees C (neutral temperature) in 29 young women with and without cold constitution. The subjects were classified into 3 groups according to their experiences with cold constitution: cold constitution, intermediate, and normal groups. Foot skin temperature was measured by thermography. Thermal sensations were measured on the dorsum of the left foot using a thermal stimulator. Cold and warm spots on the dorsum of the right foot were ascertained. Thermal stimulation was delivered by a copper probe. No significant differences in foot skin temperature among these 3 groups were identified as measured in a laboratory under neutral temperature conditions. However, the mean warm sensation threshold was +6.3+/-1.09 degrees C (mean+/-SEM) for the cold constitution group (n=14), +3.4+/-2.10 degrees C (mean+/-SEM) for the intermediate group (n=7), and -0.25+/-1.96 degrees C (mean+/-SEM) for the normal group (n=6). The difference was significant between the cold constitution and normal groups. No significant differences among the 3 groups were found in the cold sensation threshold. This may be attributable to the distribution of thermal receptors and to chronically reduced blood flow in subcutaneous tissues, where the skin temperature receptors responsible for temperature sensation are located.  相似文献   
76.
DNA samples from 21 unrelated Japanese patients with Duchenne muscular dystrophy (DMD) with nondeletion-type abnormality in the dystrophin gene and three samples from possible deletion carriers were analyzed using pulsed-field gel electrophoresis (PFGE). Among the 21 patients, 7 were found to carry partial duplications of the dystrophin gene spanning 50–400 kb. Of these 7 patients, 4 carried duplications corresponding to the major hot-spot regions for deletions (7.5–8.5 kb from the 5 end of cDNA), whereas two cases contained duplications in a region about 10 kb from the 5 end of cDNA, where causative mutations are reported to be rare. Only 1 case was found to contain a duplication of a region about 1 kb from the 5 end of cDNA, which is the reported duplication prone region. A combination of Southern blot analyses of conventional agarose gel electrophoresis and PFGE was confirmed to be useful, not only for detecting duplications and deletions, per se, but also for identifying carriers in the affected family.  相似文献   
77.
It was recognized that Geotrichum candidum Link which was selected as the efficient lipase producer formed lipase only in the presence of substrate or its relating compounds such as oils or fatty acids in a cultivation medium. From the experimental results obtained by the cultivation of the microorganism and also by using of washed cells, it seemed that lipase was formed inducibly. It is likely that the produced lipase is localized around the cell wall and membrane and it is released from the cells after a certain period from the inducible synthesis.  相似文献   
78.
The metabolic fates of the carbon skeletons of L-(U-14C)arginine, proline and glutamic acid were investigated in growing rats fed with diets containing different percentages of protein calories (0, 5, 10, 15 and 30 PC%) at 4100 kcal of metabolizable energy per kg of diet.

The incorporation of 14C into body protein at 12hr after the injection of 14C-arginine was more than 50% of the dose in all dietary groups, showing a high efficiency of utilization of this amino acid for protein synthesis. The incorporation of 14C into body protein from 14C-proline was most increased in the 15 PC% group, and the values were reduced in rats fed with lower and higher PC% diets. The carbon skeleton of 14C-glutamic acid was extensively oxidized to expired carbon dioxide, and the 14C incorporation into body protein was markedly less. The pattern of expired 14C02 production from each 14C-amino acid was in inverse proportion to that of 14C incorporation into body protein. The results indicate that the metabolic responses of arginine, proline and glutamic acid to dietary protein change at 10 to 15 PC%, where the growth rate reached its approximate maximum.  相似文献   
79.
Over the past three decades, L-proline has become recognized as an important metabolite for trypanosomatids. It is involved in a number of key processes, including energy metabolism, resistance to oxidative and nutritional stress and osmoregulation. In addition, this amino acid supports critical parasite life cycle processes by acting as an energy source, thus enabling host-cell invasion by the parasite and subsequent parasite differentiation. In this paper, we demonstrate that L-proline is oxidized to Δ1-pyrroline-5-carboxylate (P5C) by the enzyme proline dehydrogenase (TcPRODH, E.C. 1.5.99.8) localized in Trypanosoma cruzi mitochondria. When expressed in its active form in Escherichia coli, TcPRODH exhibits a Km of 16.58±1.69 µM and a Vmax of 66±2 nmol/min mg. Furthermore, we demonstrate that TcPRODH is a FAD-dependent dimeric state protein. TcPRODH mRNA and protein expression are strongly upregulated in the intracellular epimastigote, a stage which requires an external supply of proline. In addition, when Saccharomyces cerevisiae null mutants for this gene (PUT1) were complemented with the TcPRODH gene, diminished free intracellular proline levels and an enhanced sensitivity to oxidative stress in comparison to the null mutant were observed, supporting the hypothesis that free proline accumulation constitutes a defense against oxidative imbalance. Finally, we show that proline oxidation increases cytochrome c oxidase activity in mitochondrial vesicles. Overall, these results demonstrate that TcPRODH is involved in proline-dependant cytoprotection during periods of oxidative imbalance and also shed light on the participation of proline in energy metabolism, which drives critical processes of the T. cruzi life cycle.  相似文献   
80.
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