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21.
The role of bcl-2 family of genes during kindling   总被引:6,自引:0,他引:6  
Akcali KC  Sahiner M  Sahiner T 《Epilepsia》2005,46(2):217-223
PURPOSE: Several experimental models of human temporal lobe epilepsy have shown that apoptotic death of neurons is an important part of this degenerative disease. However, the role of apoptotic regulators is not clear during the epileptogenesis. Therefore we investigated the expression pattern of bcl-2 family of genes during the formation of kindling model of epilepsy in rats. METHODS: We examined the expression pattern of bax, bcl-2, bcl-xL, mtd, and bcl-w both at messenger RNA (mRNA) and protein level in the brain tissues during the formation of epilepsy with kindling model in adult rats, which has been the most acceptable form of experimental model of human epilepsy. We also assessed the onset of DNA fragmentation by using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. RESULTS: Animals have started to have epileptic discharges after day 10 of kindling model. Recurrent subthreshold electrical stimuli induced not only epileptic foci but also the expression of bax, an inducer of apoptosis, in this time period. Conversely, bcl-xL, which is an inhibitor of apoptosis, had an opposite pattern of expression both at mRNA and protein level during the formation of epilepsy. We did not observe DNA fragmentation by TUNEL staining. CONCLUSIONS: Our study shows differential expression of Bax and Bcl-xL at the CA1 region during the formation of hippocampal kindling model. The absence of DNA fragmentation during this period suggests that epileptic changes in neurons have the potential to induce DNA fragmentation by altering the expression levels of Bax and Bcl-xL.  相似文献   
22.
This study analyzes the age and gender related risk-taking behaviors of Turkish adolescents in an urban sample. A self-report risk taking scale was administered to 280 adolescents between the ages of 12-21. Results revealed that both the type and the frequency of risk-taking behaviors were changed according to age and gender. All risky behaviors except hitchhiking increased until the college level and than decreased. Boys outperformed the girls in most of the risk-taking behaviors.  相似文献   
23.
The lipid-lowering drugs, statins, induce apoptosis in a variety of tumor cells. Here we investigated the apoptotic effect of the lipophilic statin, simvastatin, in C6 glioma cells and the underlying effects on intracellular signal transduction. Simvastatin inhibited cell proliferation totally after 20 h of treatment as shown by the decrease in proliferating cell nuclear antigen expression in the nucleus. Subsequently, simvastatin caused apoptotic cell death by shrinkage of cytoplasm and condensation of chromatin, and DNA fragmentation. The features of apoptosis were visible only after 48 h of treatment, possibly reflecting a requirement for cell commitment to growth arrest. In immunocytochemical and immunoblotting experiments we have shown that simvastatin markedly increased the phosphorylation of ATF-2 and c-jun in the nucleus of the C6 glioma cells at early time points which was preserved even 24 h after treatment. In contrast, activities of protein kinases Erk1/2 and AKT in the cell survival pathway remained unchanged throughout the treatment. Selective inhibitor of JNK, but not p38 kinase, reduced simvastatin-induced cell death and ATF-2 and c-jun phosphorylation suggesting that JNK-dependent activation of ATF-2 and c-jun may play an important role in simvastatin-induced proliferation inhibition and apoptosis in C6 glioma cells. These observations suggest that statins may have clinical significance in the prevention of glial tumors beyond their cholesterol-lowering effect and JNK may be a rational target for sensitizing glioma cells to chemotherapeutic agents.  相似文献   
24.
We present a male infant with hydrocephalus, cleft lip/palate, micrognathia, club foot, laryngeal stenosis and ostium secundum type atrial septal defect. The karyotype was 46 XY. The combination of malformations observed overlaps with the characteristic findings of hydrolethalus syndrome, Meckel syndrome, Smith-Lemli-Opitz syndrome and pseudotrisomy 13. We discussed the differential diagnosis of the case.  相似文献   
25.
Aim: Modified docetaxel, cisplatin, and 5-fluorouracil (mDCF) therapy has been shown to be a well tolerated and highly effective regimen for metastatic gastric carcinoma. Herein we investigated the effectiveness of the mDCF combination as the first-line treatment in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (HNSCC).

Methods: A total of 80 patients with recurrent/metastatic HNSCC who were treated with mDCF between 2009 and 2015 were enrolled into this study. All patients were treated in the first-line with 2–6 cycles of mDCF chemotherapy which consisted of docetaxel 60?mg/m2 intravenously (IV) on day 1, cisplatin 60?mg/m2 IV on day 1, and 5-fluorouracil 600?mg/m2 IV for 5 days of continuous infusion, with cycles repeated every 21 days.

Results: The most common grade 3–4 toxicities were neutropenia (22.5%), anemia (10%), thrombocytopenia (7.5%), nephrotoxicity (1.3%), hepatotoxicity (1.3%), and diarrhea (2.5%). Twelve patients (15%) experienced a febrile neutropenic episode. Dose modification was required in 22 (27.5%) of the patients due to drug toxicity. Complete response was achieved in 2.5% of all patients, while partial and stable responses were reported to be 43.8% and 25%, respectively, with a disease control rate of 71.3%. The median progression-free and overall survival was 7 (95% CI: 5.3–8.6) and 11.5 (95% CI: 9.4–13.7) months, respectively.

Conclusions: The efficiency of the mDCF combination for induction chemotherapy has been well established previously. To our knowledge, this is one of the largest studies evaluating the survival and safety significance of mDCF chemotherapy as a first-line treatment in patients with recurrent/metastatic HNSCC.  相似文献   
26.
In this study, six new 2,2,7,7-tetramethyl-9-aryl-2,3,4,5,6,7,9,10-octahydro-1,8-acridinedione derivatives (1-6) were synthesised and their functional effects on vascular potassium channels and mechanism of induced relaxations on phenylephrine-induced contractile responses in isolated rat mesenteric arteries were investigated. Pinacidil was used as standard potassium channel opener. Compounds 1, 2, 5, 6 and pinacidil induced concentration-dependent relaxation response of vessel rings previously contracted with phenylephrine.  相似文献   
27.
Nanoparticulate systems have been receiving a significant attention especially for the treatment of cancer but one of the main hurdles is to produce these developed and high-tech nanosystems in large quantities. Anticancer drug formulations are generally designed for parenteral administrations but oral administration is still the most convenient route. In this study, orally applicable nano-sized chitosan nanoparticles (NPs) were successfully prepared using Nano Spray Dryer. It is possible to produce these NPs in large quantities by simply increasing the processing time using the machine without changing any parameter. A chemotherapeutic agent (imatinib mesylate; IMA) and nonsteroidal anti-inflammatory drug (dexketoprofen trometamol) were loaded together in these NPs. NPs were also functionalized with polyethylene glycol and folic acid to obtain long circulating NPs and tumor targeting. The antitumoral activities of formulations showed that these developed NPs can enhance the effectiveness. Animal experiments were performed on fibrosarcoma-bearing mice model, and the treatment with 0.8 mg/μL/kg IMA-loaded chitosan NPs was found to be successful to slow down the growth of tumors. The tumor tissues were removed from the animals and enzymatic activities were evaluated. The inhibitory effect of tyrosine kinase was found to be enhanced from 36.4% to 68.4% when IMA was used in combination with dexketoprofen trometamol. Furthermore, all dried NPs were found to be stable for more than a year at 25°C. Presented results show that these developed combinatorial drug–loaded NPs can be used for the treatment of fibrosarcoma, and these data can provide an insight, new strategies for productions or alternatives in cancer treatment.  相似文献   
28.
In this study, honey locust gum (HLG) obtained from Gleditsia triacanthos (honey locust) beans was investigated as a hydrophilic matrix material in the tablets prepared at different concentrations (5% and 10%) by wet granulation method. Theophylline was chosen as a model drug. The matrix tablets containing hydroxyethylcellulose and hydroxypropyl methylcellulose as sustaining polymers at the same concentrations were prepared and a commercial sustained release (CSR) tablet containing 200 mg theophylline was examined for comparison of HLG performance. Physical analysis on CSR tablet, matrix tablets and their granules before compression were performed. According to the results obtained from dissolution studies in distilled water, pH 1.2 HCl buffer and pH 7.2 phosphate buffer, no significant difference was found between CSR tablet and the matrix tablet containing 10% HLG in each medium (P > 0.05) and these tablets showed zero-order kinetic model in all the mediums.  相似文献   
29.
Endothelial IKCa and/or SKCa channels play an important role in the control of vascular tone by participating in endothelium‐dependent relaxation. Whether β‐AR antagonists, mainly used in hypertension, affect endothelial KCa channel function is unknown. In this study, we examined the effect of the β2‐AR antagonist and inverse agonist ICI 118,551 on the IKCa/SKCa channel activity by assessing functional relaxation responses to several agonists that stimulate these channels. Mesenteric arterial rings isolated from male Sprague Dawley mounted to organ baths. Acetylcholine elicited IKCa‐ and SKCa‐mediated relaxations that were abolished by TRAM‐34 and apamin, respectively. ICI 118,551, which did not dilate the arteries per se, increased the IKCa‐mediated relaxations, whereas SKCa‐mediated relaxations remained unaltered. Same potentiating effect was also detected on the IKCa‐mediated relaxations to carbachol and A23187, but not to NS309. Neither acetylcholine‐induced nitric oxide‐mediated relaxations nor SNP relaxations changed with ICI 118,551. The PKA inhibitor KT‐5720, the selective β2‐AR agonist salbutamol, the selective β2‐AR antagonist butoxamine, the non‐selective β‐AR antagonist propranolol, and the inverse agonists carvedilol or nadolol failed to affect the IKCa‐mediated relaxations. ICI 118,551‐induced increase was not reversed by salbutamol or propranolol as well. Besides, low potassium‐induced relaxations in endothelium‐removed arteries remained the same in the presence of ICI 118,551. These data demonstrate a previously unrecognized action of ICI 118,551, the ability to potentiate endothelial IKCa channel‐mediated vasodilation, through a mechanism independent of β2‐AR antagonistic or inverse agonistic action. Instead, the enhancement of acetylcholine relaxation seems likely to occur by a mechanism secondary to endothelial calcium increase.  相似文献   
30.
Solid lipid ketoprofen micropellets (SLKM) at different drug/beeswax ratios [(1:1) and (1:2)] were prepared by emulsion congealing technique and then compressed into tablets. Ketoprofen in solid state was incorporated into the melted beeswax at 90 degrees C and the mixture was emulsified in the hot aqueous Tween 80 solution by stirring at a constant rate. The SLKM were obtained by cooling the coarse emulsion down to room temperature and filtering. Drug entrapment efficiency and particle size analysis by laser diffractometry (LD) were determined, and existence of a drug-lipid interaction was investigated by differential scanning calorimetry (DSC) on the SLKM, before being compressed into the tablets by direct compression method. Finally, in vitro release studies were performed and the release kinetics of the waxy tablets were calculated. A commercial ketoprofen retard tablet (reference: Profenid Retard 200 mg) was also examined to compare the release properties. While the data obtained from DSC were indicating absence of drug-lipid interaction in the SLKM, it was determined that 28.62% (+/-2.08), 38.60% (+/-1.91) and 47.00% (+/-1.82) of ketoprofen was released from the tablets containing (1:2) and (1:1) SLKM and Profenid Retard 200 mg in pH 7.4 phosphate buffer solution after 8 h, respectively.  相似文献   
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