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101.

Background:

We evaluated the in vivo activity of Bunium persicum (Boiss) essential oil on infected mice with acute toxoplasmosis.

Methods:

To evaluate prophylactic effects, male NMRI mice received B. persicum essential oil at the concentrations of 0.05 and 0.1 mL/kg for 14 days. After 24 h mice were infected intraperitonealy with 1×104 tachyzoites of T. gondii, RH strain. In order to investigate therapeutic effects, mice were infected and then received B. persicum oil at the concentrations of 0.05 and 0.1 ml/kg two times a day for 5 days. The time/mean time of death in all infected mice and the number of tachyzoites from infected mice were recorded.

Results:

The time/mean time of death of infected mice was 8 and 9 days after oral administration of B. persicum oil at the concentration of 0.05 and 0.1 mL/kg, respectively (P<0.05). In contrast, the time/mean time of death control group was 5 days. In addition, B. persicum significantly reduced the mean number of tachyzoites compared with control group. The time/mean time of death of infected mice was 6 and 7 days after oral administration of B. persicum essential oil at the concentration of 0.05 and 0.1 mL/kg, respectively. In contrast, the time/mean time of death control group was 5 days. B. persicum especially at the concentration of 0.1 ml/kg significantly reduced the mean number of tachyzoites compared with control group.

Conclusion:

The results showed the potential of B. persicum essential oil as a natural source for the production of new prophylactic agent for use in toxoplasmosis.  相似文献   
102.

Background

Tramadol is an opioid, synthetic analog of codeine and has been used for the treatment of acute or chronic pain may be abused. In this work, a developed Dispersive liquid liquid microextraction (DLLME) as binary solvents-based dispersive liquid-liquid microextraction (BS-DLLME) combined with high performance liquid chromatography (HPLC) with fluorescence detection (FD) was employed for determination of tramadol in the urine samples. This procedure involves the use of an appropriate mixture of binary extraction solvents (70 μL CHCl3 and 30 μL ethyl acetate) and disperser solvent (600 μL acetone) for the formation of cloudy solution in 5 ml urine sample comprising tramadol and NaCl (7.5%, w/v). After centrifuging, the small droplets of extraction solvents were precipitated. In the final step, the HPLC with fluorescence detection was used for determination of tramadol in the precipitated phase.

Results

Various factors on the efficiency of the proposed procedure were investigated and optimized. The detection limit (S/N = 3) and quantification limit (S/N = 10) were found 0.2 and 0.9 μg/L, respectively. The relative standard deviations (RSD) for the extraction of 30 μg L of tramadol was found 4.1% (n = 6). The relative recoveries of tramadol from urine samples at spiking levels of 10, 30 and 60 μg/L were in the range of 95.6 – 99.6%.

Conclusions

Compared with other methods, this method provides good figures of merit such as good repeatability, high extraction efficiency, short analysis time, simple procedure and can be used as microextraction technique for routine analysis in clinical laboratories.  相似文献   
103.
The global pandemic of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created an urgent need for effective antivirals. Remdesivir (formerly GS-5734) is a nucleoside analogue pro-drug currently being evaluated in COVID-19 clinical trials. Its unique structural features allow high concentrations of the active triphosphate metabolite to be delivered intracellularly and it evades proofreading to successfully inhibit viral RNA synthesis. In pre-clinical models, remdesivir has demonstrated potent antiviral activity against diverse human and zoonotic β-coronaviruses, including SARS-CoV-2. In this article, we critically review available data on remdesivir with an emphasis on biochemistry, pharmacology, pharmacokinetics, and in vitro activity against coronaviruses as well as clinical experience and current progress in COVID-19 clinical trials.  相似文献   
104.
BackgroundDiabetes mellitus (DM) is a well-known clinical entity with various late complications. There is a surge of research aiming to use the medical herb in the management of DM.ObjectiveThis study aimed to investigate whether the alleviation of DM by an isolated compound from Rosa canina is mediated by DNA methylation in STZ-diabetic rats.MethodsSixty adult Wistar male rats were classified into control, diabetic and treatment groups. Rats were treated with STZ (40 mg/kg), metformin (500 mg/kg), and oligosaccharide fraction (OF; 10, 20 and 30 mg/kg) isolated from Rosa canina. DNA was extracted from the blood and pancreas to determine DNA methylation using the Global DNA Methylation kit. The expressions of DNA methyltransferases (Dnmts), PDX1, Ins1, GCK and PTP1B2 were determined by using qRT-PCR.ResultsThe significant blood glucose-lowering potential of OF was associated with a reduced level of global DNA methylation (p < 0.05). The expression levels of Dnmts 1 and increased in the pancreas and blood from diabetic rats compared to control group which declined by OF treatment (p < 0.05). Paradoxically, the expression of Dnmt 3β augmented in the pancreas and blood of OF group compared to diabetic ones (p < 0.05). Besides, the expressions of Pdx1, PTP1B2, Ins1 and GCK increased in OF-treated rats compared to diabetic groups.ConclusionResults revealed that DNA methylation plays a causal role in the effectiveness of the isolated OF. Furthermore, the possible regenerative potential of oligosaccharide in diabetic rats may have contributed to the modulation of DNA methylation.Graphical abstractElectronic supplementary materialThe online version of this article (10.1007/s40199-020-00363-8) contains supplementary material, which is available to authorized users.  相似文献   
105.
Signaling via interleukin-2 receptor (IL-2R) is a requisite for regulatory T (Treg) cell identity and function. However, it is not completely understood to what degree IL-2R signaling is required for Treg cell homeostasis, lineage stability and function in both resting and inflammatory conditions. Here, we characterized a spontaneous mutant mouse strain endowed with a hypomorphic Tyr129His variant of CD25, the α-chain of IL-2R, which resulted in diminished receptor expression and reduced IL-2R signaling. Under noninflammatory conditions, Cd25Y129H mice harbored substantially lower numbers of peripheral Treg cells with stable Foxp3 expression that prevented the development of spontaneous autoimmune disease. In contrast, Cd25Y129H Treg cells failed to efficiently induce immune suppression and lost lineage commitment in a T-cell transfer colitis model, indicating that unimpaired IL-2R signaling is critical for Treg cell function in inflammatory environments. Moreover, single-cell RNA sequencing of Treg cells revealed that impaired IL-2R signaling profoundly affected the balance of central and effector Treg cell subsets. Thus, partial loss of IL-2R signaling differentially interferes with the maintenance, heterogeneity, and suppressive function of the Treg cell pool.  相似文献   
106.
107.
Quality of Life Research - Pulmonary complications are among the major disadvantages of burns. The present study aimed to determine the effect of inspiratory muscle training on respiratory muscle...  相似文献   
108.
Fluoxetine is one of the most commonly used antidepressants. Fluoxetine could prevent the mesenchymal stem cell differentiation in lung fetus of rat. Moreover, the mesenchymal stem cells are also present in adult tissues. Therefore, in the current study, we aimed to investigate the effects of fluoxetine (FLX) on both proliferation and adipogenic/osteogenic differentiation of human adipose‐derived stem cells (ADSCs). After culturing of human ADSCs, these cells were treated with two concentrations of FLX (10 and 20 μm ). Then, cells were differentiated by adding osteogenic and adipogenic media. The effect of FLX on human ADSCs proliferation was evaluated by MTT assay. Fluoxetine role on adipogenic and osteogenic differentiation of human ADSCs was analyzed by oil red and alizarin red staining and RT‐PCR reaction. According to MTT assay, FLX showed a time‐ and concentration‐dependent proliferation response and eventually decreased human ADSCs proliferation. RT‐PCR analysis indicated that FLX significantly diminished the expression of osteogenesis‐related genes such as RUNX2 and alkaline phosphatase (ALP). Data also revealed a significant reduction in the expression of peroxisome proliferator‐activated receptor γ (PPARγ) and fatty acid‐binding protein (FABP) (specific genes of adipogenic lineage). In addition, FLX decreased mineralized matrix and the amount of lipid droplets in human ADSCs by staining methods. Our observation demonstrated that the effects of FLX may be time‐dependent. This drug possesses an increasing phase in proliferation and survival of human ADSCs (first 24 h) following a decreasing phase (after 48 h). Moreover, FLX could attenuate both osteogenic and adipogenic differentiation of human ADSCs.  相似文献   
109.
In this study, we were aimed to evaluate the probable effect of the crud extract of Silybum marianum, with high polyphenolic content, on experimental nonalcoholic steatohepatitis (NASH). To induce NASH, a methionine and choline deficient (MCD) diet was given to N-Mary rats for 8 weeks. After NASH development, MCD-fed rats were divided into two groups: MCD groups received MCD diet and MCD + S group was fed MCD diet plus crude extract of S. marianum orally for 3 weeks. Control group was fed a normal diet for 11 weeks. Finally, all rats were sacrificed. Plasma alanine amino transferase (ALT) and aspartate amino transferase (AST) levels were evaluated. In addition, the following hepatic factors were also evaluated: liver histology, malondialdehyde (MDA) and reduced glutathione (GSH) contents, gene expressions of TNF-α and TGF-β and immunoblot evaluations of caspase-3, ERK/p-ERK, JNK/pJNK and p38/pp38. Histopathological evaluations of the liver samples revealed that treatment with the S. marianum extract has abated the severity of NASH among the MCD-fed rats. Also, a significant reduction was observed in the sera ALT and AST activities. In addition, the extract caused dramatic reduction in the elevated hepatic TNF-α and TGF-β mRNA and MDA levels along with an increase in the GSH content. Moreover, the plant extract treatments significantly lowered activation of procaspase-3 to active caspase-3 and also lowered the phosphorylated form of JNK among the same group of rats. These results suggest that the S. marianum crude extract beneficial effects on NASH are mainly due to its antioxidant and anti-inflammatory activities.  相似文献   
110.

Purpose

Finding a novel biomarker for determining the radiosensitivity of colorectal cancer (CRC) is critical. The aim of this study is to evaluate the role of two main miRNAs including miR-222 and miR-155 in radiation response of CRC.

Materials and methods

The radioresistant CRC cell lines were established by exposing the HCT 116 cell line to fractional X-ray radiation. SubG1 fraction analysis, MTT and clonogenic assays were applied to evaluate acquired radioresistant cell line radiosensitivity. miR-222/PTEN and miR-155/FOXO3a expressions were detected by RT PCR.

Results

The clonogenic assay and sub-G1fraction analysis indicated that the RR2 sub-line was significantly more resistant than the parental cell line. MiR-222 and miR-155 were significantly upregulated in the radioresistant cell lines compared with the parental cell lines. The PTEN and FOXO3a expressions in the radioresistant cell lines were significantly higher than in the parental line.

Conclusion

These observations indicate that miR-222 and miR-155 could induce radiation resistance in colorectal cancer by targeting PTEN and FOXO3a genes, respectively. Therefore, miR-222 and miR-155 can be suggested as good biomarkers of CRC radiation response.
  相似文献   
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