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11.
Using cytophotometric method, the content of glycogen was studied in hepatocytes of the portal and central zones of a liver lobule in norm, in cirrhosis, and 1, 3, and 6 months after a partial hepatectomy of the normal and cirrhotic rat liver. As we showed earlier, glycogen content in cirrhotic liver hepatocytes rose 2-3-fold, along with obvious impairment of glycogen metabolic heterogeneity in these. In cirrhotic liver glycogen dominates in the central zone, whereas in norm more glycogen is observed in the portal one. The objective of this study was to find out to what degree a partial hepatectomy of cirrhotic liver may promote recovery of the metabolic glycogen heterogeneity in hepatocytes. Glycogen was determined in hepatocytes, using a quantitative variant of PAS-reaction on sections of the material obtained from serial supravital punctate liver biopsies. Glycogen amount in hepatocytes of different liver lobule zones was determined by an image analyzer technique that allows to bring together the cytophotometric analysis of the substance with its localization in a particular liver lobule. Results of these studies have shown that a partial hepatectomy of cirrhotic liver promotes restoration of the hepatocyte metabolic heterogeneity in the liver lobule.  相似文献   
12.
Application of partition test measuring the behavioural activity of animals near the transparent perforated partition (dividing the experimental cage onto two halves) as a reaction to the partner in the neighbouring compartment of common cage, is considered. Behavioural reaction as a response to other individual differs in dependence on psychological and physiological states, social experience, strains of the animals and kinds of partner. Partition test may be productive in experiments studying mechanisms of sociability, anxiety, aggressive and sexual motivations, olfaction, as well as for screening of psychotropic drugs.  相似文献   
13.
The principles of the primary prophylaxis, analogous to the program "Harm Reduction", are presented. The basis for placing this work on broad footing was the rapid assessment of the situation with the use of narcotic drugs in the city (the number of users exceeded 10,000 per 238,000 inhabitants) with a tendency towards a sharp decrease of the age of the users (9-13 years). The experience of work on the training of medical personnel, directly contacting with blood and thus considered to be a risk group, taking into account risky professional behavior (potentially dangerous), was accumulated. The training activities among students of medical schools proved to be effective. They became the best volunteers and leaders among young people. Adolescents aged 14-18 years were enlisted as volunteers: they worked in different places usually attended by young people and invited drug addicts to the anonymous examination room. The role of local mass media in educating the public on of the problems of the prevention of HIV infection is discussed. As a result, the activation of the youth movement in support of the program "Anti-AIDS" and an increase in the number of people in target groups coming to the anonymous examination room are noted.  相似文献   
14.
Concentrations of the total glycogen (TG) and of its labile and stable fractions (LF and SF, respectively) were determined in hepatocytes of portal and central zones of the normal human liver and in the liver of patients with cirrhosis of viral and alcohol etiology. Using the PAS reaction, TG and its LF and SF were revealed in histological sections of the material obtained by liver punction biopsies. Concentrations of TG and its fractions were measured by television cytophotometry. In liver cirrhosis, concentrations of TG, LF, and SF in both zones of the hepatic lobule were much higher than in the normal liver. The ratio between hepatocyte TG concentration in the portal zone and that in the central zone (P/C ratio), both in norm and in viral cirrhosis, exceeds 1.0 to reach, respectively, 1.26 +/- 0.02 and 1.03 +/- 0.01. The glycogen fraction composition in cells of both liver lobule zones in viral cirrhosis does not significantly differ from that in norm. On the contrary, in the liver of patients with alcoholic cirrhosis, the P/C ratio falls to 0.82 +/- 0.02 to be accompanied by qualitative changes in glycogen composition.  相似文献   
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A combined method, that allows measuring glycogen and DNA contents in one of the same cell, was applied for quantitative determination of these in mono- and binucleate hepatocytes with different ploidy obtained from adult rats. The mean glycogen content was shown to increase proportionally to the genome number within the changes of the hepatocyte ploidy from 2 to 8c.  相似文献   
17.
The effect of temperature, pH, and concentration of potassium periodate solution on the intensity of fluorescence PAS-reaction was studied. The reaction was shown to be most specific in respect to glycogen at the temperature of oxidizer 4 degrees C (optimal time of oxidation being 10-12 hr). Similar results were also obtained at 20 degrees (optimal time of oxidation being 1.5 hr). Under these conditions the curve of dependence of the reaction intensity on the time of auramine-SO2 treatment double-stepped character which can be due to the presence of two glycogen fractions in hepatic cells. The fluorescence PAS-reaction intensity varied in significantly when the periodate concentration changed from 0.8 to 1.2% (from 0.2 to 0.8%) it gradually increased and pH -from 2.0 to 6.0.  相似文献   
18.

Background

Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals.

Methods

We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle.

Results

The 50% effective inhibitory concentration (IC50) of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus.

Conclusions

To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-μM) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent.  相似文献   
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20.

Background

Hormone-refractory prostate cancer (HRPC), which is resistant to hormone therapy, is a major obstacle in clinical treatment. An approach to inhibit HRPC growth and ultimately to kill cancers is highly demanded.

Results

KUD773 induced the anti-proliferative effect and subsequent apoptosis in PC-3 and DU-145 (two HRPC cell lines); whereas, it showed less active in normal prostate cells. Further examination showed that KUD773 inhibited tubulin polymerization and induced an increase of mitotic phosphoproteins and polo-like kinase 1 (PLK1) phosphorylation, indicating a mitotic arrest of the cell cycle through an anti-tubulin action. The kinase assay demonstrated that KUD773 inhibited Aurora A activity. KUD773 induced an increase of Cdk1 phosphorylation at Thr161 (a stimulatory phosphorylation site) and a decrease of phosphorylation at Tyr15 (an inhibitory phosphorylation site), suggesting the activation of Cdk1. The data were substantiated by an up-regulation of cyclin B1 (a Cdk1 partner). Furthermore, KUD773 induced the phosphorylation and subsequent down-regulation of Bcl-2 and activation of caspase cascades.

Conclusions

The data suggest that KUD773 induces apoptotic signaling in a sequential manner. It inhibits tubulin polymerization associated with an anti-Aurora A activity, leading to Cdk1 activation and mitotic arrest of the cell cycle that in turn induces Bcl-2 degradation and a subsequent caspase activation in HRPCs.  相似文献   
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