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41.
Several substituted 3-aryl-1-(4-aryl-2-thiazolyl)-5-(3-pyridyl)-2-pyrazolines were synthesized by reacting substituted 3-aryl-5-(3-pyridyl)-1-thiocarbamoyl-2-pyrazolines with phenacyl bromide in ethanol. The structures of all compounds were confirmed by IR, (1)H-NMR, mass spectral data and elemental analyses. The antihypertensive activity of compounds was examined by the tail-cuff method and compared with clonidine. Compounds 24-28 showed significant antihypertensive activity.  相似文献   
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The effects of macerated extracts of Crocus sativus (Family Iridaceae) (saffron) on cell viability and cytokine release of stimulated peripheral blood mononuclear cells by phytohemagglutinin (PHA) and nonstimulated cells were examined. The effects of three concentrations of macerated extract, dexamethasone, and saline on cell viability and production of cytokines, including interleukin (IL)-4, IL-10, and interferon-γ (IFN-γ) were evaluated. In cells stimulated with PHA, different concentrations of the extract significantly inhibited cell viability of lymphocytes (P<.001 for all concentrations). High concentrations of the extract (500 μg/mL) also inhibited secretion of IFN-γ in stimulated cells and IL-10 secretion in both stimulated and nonstimulated cells (P<.05 for all cases). The effects of high and low concentrations of the extract (500 and 50 μg/mL, respectively) on IL-4 secretion were lower than that of dexamethasone (P<.05 to P<.001). The extract showed a stimulatory effect on IFN-γ and IL-4 secretion in nonstimulated cells. The ratios of IFN-γ to IL-4 in the presence of all concentrations of saffron on stimulated cells were significantly higher than for the control group (P<.05 to P<.01). These results indicated that the extract of saffron leads to increased ratio of IFN-γ to IL-4.  相似文献   
45.

Background

The aim of this study is to investigate the pattern of changes in serum albumin level after mini-gastric bypass (MGB) and its association with gender, age, and body mass index (BMI) of the patients.

Methods

This cohort study was conducted on 196 morbidly obese patients undergoing MGB followed for 1 year. The data on BMI, serum albumin level, demographic, anthropometric, biochemical variables and comorbidities were gathered before and after (3, 6, and 12 months) surgery. The trend of changes in BMI and serum albumin of the patients was investigated by repeated measures tests using general linear model (GLM) and generalized estimating equations (GEE) approaches.

Results

The mean age, baseline median BMI, and albumin of the patients were 41.34 ± 11.03 years, 44.54 kg/m2, and 4.00 g/dl, respectively. There was a chronologically significant trend of decline in BMI (P < 0.001). GEE demonstrated no chronologically significant trend in serum albumin (P = 0.278). The trend of changes in albumin was significantly associated only with age grouping and baseline serum albumin level (P = 0.017 and 0.001, respectively). This trend had fluctuations in patients older than 40 years with baseline serum albumin level of 3.50–3.90 g/dl. For patients with any age and baseline serum albumin level of 4.00–4.90 g/dl, this trend was stable in all periods of follow-up.

Conclusion

MGB is an effective technique to lose weight. The trend of changes in serum albumin level was affected by its baseline levels and age.
  相似文献   
46.

Introduction

The objective was to determine the effect of isolated soy protein (ISP) and flaxseed oil (FO) on inflammatory and oxidative stress indices, acute phase proteins, and wound healing of burn patients.

Methods

One hundred eighty-eight patients were assessed for eligibility in this randomized controlled trial. Of these, seventy-three eligible patients (total burn surface area 20–50%) were randomly assigned to 3 isocaloric groups, labeled as control (wheat flour + corn oil (CO)), ISP + FO, and ISP + CO, to receive these nutrients for 3 weeks. We used intention to treat analysis to overcome bias. Because of the large perturbation in water compartments, patients received nutrients from 4th to 25th day of admission. Serum high sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), superoxide dismutase (SOD), ferritin, albumin, and transferrin were measured. The wound area was evaluated by stereological test.

Results

During the 3-week intervention, hs-CRP (?19.4 ± 5.6, ?11.7 ± 4.7 μg/ml) and ferritin (?83.8 ± 20.5, ?80.1 ± 19.6 ng/ml) levels changes significantly reduced compared to the control group (P < 0.05). MDA level (?0.05 ± 0.21 μmol/l) significantly decreased in group A (P < 0/05) but was not significant in groups B and control (P > 0.05). Albumin level (0.59 ± 0.14, 0.30 ± 0.12 g/dl) significantly increased in group A compared to the control group (P < 0.05), but no significant relationship was found between other groups (P > 0.05). Transferrin level (4.9 ± 3.6, 2.9 ± 5.1 g/dl) significantly increased in ISP groups compared to the control (P < 0.05). SOD improved in all groups with no significant difference between them (P > 0.05). The stereology examination showed significant improvement in wound healing in the ISP groups on days 22 and 25 compared to the control group.

Conclusion

Nutritional supplements with ISP may attenuate post-burn oxidative stress and inflammation, leading to improved wound healing in burn patients. Flaxseed oil may not exert a beneficial effect over the ISP.  相似文献   
47.
PurposeThe authors conducted an in vitro study to evaluate the shear bond strength of a fissure sealant to enamel pretreated with erbium, chromium: yttrium, scandium, gallium, garnet (Er, Cr: YSGG) laser or air abrasion followed by acid etching.MethodsThe authors sectioned extracted sound premolars mesiodistally and used the buccal and lingual surfaces for experimental analysis. They divided specimens randomly into three groups of 15 each according to the enamel surface pretreatment methods: group A, 37 percent phosphoric acid; group B, air abrasion followed by acid etching with 37 percent phosphoric acid; group C, irradiation with Er, Cr: YSGG laser followed by acid etching with 37 percent phosphoric acid. After applying a bonding system, the authors bonded cylinders of sealant to the enamel surfaces by using transparent gelatin tubes (0.7 millimeter in diameter and 1 mm in height) and then polymerized them. They stored all specimens in distilled water at 37°C for 24 hours. They tested shear bond strength by using a universal testing machine with a crosshead speed of 0.5 mm per second. The authors analyzed the data by means of one-way analysis of variance and Tukey-Kramer post hoc tests (α = .05).ResultsThe bond strength of group B specimens was statistically higher than those of group A and group C specimens (P < .05). The authors found no statistically significant differences in shear bond strength between surfaces treated with Er, Cr: YSGG laser and those treated with acid etching alone (P > .05).ConclusionPretreatment of enamel surfaces with air abrasion increased the bond strength of fissure sealant, but pretreatment with Er, Cr: YSGG laser did not increase the effectiveness of conventional acid etching of enamel in sealant bonds.  相似文献   
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Several neuroendocrine complications including diabetes change the morphine antinociception and the development of tolerance to the drug. Morphine antinociception was reduced significantly in morphine tolerant diabetic rats compared to the non-diabetic animals. The exact mechanism of this effect is not known. This study was performed to determine the role of nitric oxide (NO) on morphine tolerance in diabetic state. Nociceptive responses in alloxan-induced diabetic morphine tolerated rats were measured by the hot-plate test. The urinary nitric oxide level was measured spectrophotometrically with Griess reagent. For the conversion of nitrate to nitrite, vanadium chloride was used. The results showed that experimental diabetes increased morphine analgesia. Conversely, degree of tolerance to morphine was diminished in diabetic state. The urinary nitrite content in diabetic morphine tolerated rats was higher than non-diabetic groups. L-arginine significantly increased the NO production in diabetic morphine tolerated animals, whereas aminoguanidine decreased it. Appropriately, L-arginine increased the latency time of reaction to noxious stimuli in diabetic compared to non-diabetic rats. L-arginine-treated animals also showed more tolerance to morphine analgesia. As expected, aminoguanidine deducted the level of morphine tolerance in diabetic animals. It is suggested that NO has a modulatory role in the effects of diabetes on morphine analgesia and tolerance.  相似文献   
50.
The central role of Src in the development of several malignancies, including breast cancer, and the accumulating evidence of its interaction with receptor tyrosine kinases, integrins, and steroid receptors have identified it as an attractive therapeutic target. In the current study, we have evaluated the effect of a Src/Abl kinase inhibitor, SKI-606, on breast cancer growth, migration, invasion, and metastasis. Treatment of human breast cancer cells MDA-MB-231 with SKI-606 caused a marked inhibition of cell proliferation, invasion, and migration by inhibiting mitogen-activated protein kinase and Akt phosphorylation. For in vivo studies, MDA-MB-231 cells transfected with the plasmid encoding green fluorescent protein (GFP; MDA-MB-231-GFP) were inoculated into the mammary fat pads of female BALB/c nu/nu mice. Once tumor volume reached 30 to 50 mm(3), animals were randomized and treated with vehicle alone or 150 mg/kg SKI-606 by daily oral gavage. Experimental animals receiving SKI-606 developed tumors of significantly smaller volume (45-54%) compared with control animals receiving vehicle alone. Analysis of lungs, liver, and spleen of these animals showed a significant decrease in GFP-positive tumor metastasis in animals receiving SKI-606 at a dose that was well tolerated. Western blot analysis and immunohistochemical analysis of primary tumors showed that these effects were due to the ability of SKI-606 to block tumor cell proliferation, angiogenesis, growth factor expression, and inhibition of Src-mediated signaling pathways in vivo. Together, the results from these studies provide compelling evidence for the role of Src inhibitors as therapeutic agents for blocking breast cancer growth and metastasis.  相似文献   
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