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61.
Trunk muscular strength in pre-pubertal children with and without back pain   总被引:1,自引:0,他引:1  
OBJECTIVE: While in adulthood there is no proven relationship between back pain and trunk muscle strength, in pre-pubertal subjects this topic has been poorly studied. The aim of the study was to evaluate isometric and isokinetic trunk muscle strength in children with or without previous back pain. METHODS: The recent occurrence of back pain (last 6 months) among 144 children (77 males, 67 females, age 11.9 +/- 0.3 years) was assessed using a questionnaire. Extensor and flexor trunk muscle strength was measured through isometric and isokinetic (60, 90, 120 degrees/s) tests. Peak torque (PT), PT angle, PT flexor/PT extensor ratio and intra-session coefficient of variation (COV) were determined. RESULTS: Flexor and extensor muscle PT, but not PT angle, were significantly higher in males than in females, irrespective of back pain occurrence. PT flexor/PT extensor ratio at 90 degrees angular velocities increased significantly only in males with back pain, compared with males without back pain. The COV trend was similar for flexor and extensor muscles. CONCLUSIONS: Isometric and isokinetic trunk muscle strength probably play a minor role in back pain occurrence in children. The isokinetic testing velocity may be important in determining trunk strength differences between children with and without back pain.  相似文献   
62.
Hemolytic effects of water-soluble fullerene derivatives   总被引:3,自引:0,他引:3  
A series of water-soluble fullerene C(60) derivatives has been investigated for their cytotoxic and hemolytic properties, with the aim to correlate structure with toxicity. We observed that cationic chains induce significant toxicity while the presence of neutral or anionic moieties did not produce any response in our model. A validation of these experimental observations has been performed by theoretical studies in which hydrophilic and hydrophobic surface areas were correlated quantitatively with hemolytic properties.  相似文献   
63.
64.
Apoptosis induced by oxaliplatin in human colon cancer HCT15 cell line   总被引:8,自引:0,他引:8  
BACKGROUND: Oxaliplatin (L-OHP), active in a wide range of human and animal tumours, also CDDP-resistant, possesses unique molecular characteristics of action. However, the mechanisms by which the damage induced by L-OHP triggers a death signal are not yet fully defined. MATERIALS AND METHODS: After L-OHP treatment of the HCT15 human colon cancer cell line, apoptosis was evaluated by DNA laddering detection and by flow cytometry; the effect on specific caspase-3, -8 and -9 inhibitors, mitochondrial membrane permeability transition, cytochrome C release and expression of CD95 and CD95L were also assessed. RESULTS: HCT15 cells underwent apoptosis when treated with all used drug concentrations (7-25 microM). Treatment of cells with L-OHP resulted in the activation of caspase-8, -9 and -3, in a mitochondrial membrane depolarisation, and in an increase of CD95 receptor and CD95 ligand levels. CONCLUSION: The results correlated well with the ability of L-OHP to induce apoptosis and give further insights into the mechanisms underlying the L-OHP-induced apoptosis of tumor cells.  相似文献   
65.
Thirteen hypertensive patients with microvascular angina were studied before and after receiving oral L-arginine (4 weeks, 2 g, 3 times daily). L-arginine significantly improved angina class, systolic blood pressure at rest, and quality of life. Maximal forearm blood flow, plasma L-arginine, L-arginine:asymmetric dimethyl arginine ratio, and cyclic guanylate monophosphate increased significantly after treatment. In medically treated hypertensive patients with micro-vascular angina, oral L-arginine may represent a useful therapeutic option.  相似文献   
66.
67.
To understand the role of several medical conditions on the risk of uterine fibroids, we analysed the findings of a large case-control study. Cases were 843 women aged 54 or less (median age 43 years, range 21-54) with histologically confirmed uterine fibroids, whose clinical diagnosis dated back no more than 2 years. Indications for surgery were recurrent menorrhagia or ultrasound evidence of fibroids larger than 10 cm in diameter. Controls were 1557 women aged 54 years or less of comparable quinquennia of age (median age 43 years, range 21-54) who had not undergone hysterectomy and were admitted for acute, non-gynecologic, non-hormonal, non-neoplastic conditions to a network of hospitals with a similar catchment area. Clinical history of severe overweight was inversely associated with the risk of fibroids (multivariate odds ratio (OR), OR: 0.6, 95% confidence intervals (CI): 0.5-0.8). An increase in the frequency of fibroids was seen in women with a history of benign breast disease (OR: 1.2, 95% CI: 0.9-1.6) and particularly of breast biopsies (OR: 2.0, 95% CI: 1.2-3.5). The results of this large dataset indicate that medical conditions known or likely to be related to female hormones are not important determinants of the risk of fibroids.  相似文献   
68.
Resveratrol, a polyphenol present in many plant species, exhibits a wide range of biological and pharmacological activities both in vitro and in vivo. It has been shown to exert a potent chemopreventive effect in carcinogenesis models and to induce cell growth inhibition and apoptosis in human tumour cells, including melanoma cells. Malignant melanoma is considered to be a chemotherapy-refractory tumour, and the commonly used anticancer drugs do not seem to modify the prognosis of metastatic disease. To further evaluate the therapeutic potential of resveratrol in the treatment of melanoma, we selected three human melanoma cell lines with different levels of resistance to temozolomide (TMZ), an antitumour triazene compound. The cell lines were subjected to resveratrol treatment and analysed for cell growth inhibition, cell cycle perturbation and apoptosis induction. We found that resveratrol markedly impaired proliferation of both the TMZ-sensitive M14 and the TMZ-resistant SK-Mel-28 and PR-Mel cell lines. The latter cell line was two-fold more resistant to the drug than M14 and SK-Mel-28 cells. The sensitivity of normal human keratinocytes to resveratrol was found to be significantly higher than that of M14 and SK-Mel-28 cells and similar to that of the PR-Mel cell line. This suggests a possible good in vivo therapeutic index for resveratrol. Our results also show that the growth-inhibitory effect of resveratrol on melanoma cells is mainly due to its ability to induce S-phase arrest and apoptosis. Taken together, our data indicate that resveratrol is an interesting candidate for the treatment of advanced melanoma.  相似文献   
69.
Children and adolescents with growth hormone (GH) deficiency (GHD) have reduced bone turnover and bone mass in comparison with normal individuals. GH replacement therapy stimulates bone turnover and improves bone mass during childhood and adolescence. At final height, patients with GHD treated with GH have normal mean values of bone mass, but some patients have reduced lumbar BMD (Z score <1) with an increased susceptibility to fractures. Children and adolescents with GHD have approximately a fourfold decreased fracture frequency during treatment in comparison with controls. The changes of bone mass during the transition to adulthood in patients with GHD who discontinued GH treatment after final height are not defined. An increase of lumbar BMD after final height has been reported until 2 years after discontinuation of GH treatment; this could be the result of a spontaneous progression towards peak bone mass or of a persisting effect of GH treatment on bone mass accumulation. GH has an important role in the accrual of bone mass during childhood and adolescence, but the impact of GHD on bone mass during the transiton to adulthood is unknown.  相似文献   
70.
The interplay between pro- and anti-inflammatory mechanisms during inflammatory and immune responses is critical for avoiding excessive tissue damage. Extracellular nucleotides (e.g., adenosine 5'-triphosphate) may represent constitutive signals that can alert the immune system of abnormal cell death. Relatively high doses of nucleotides induce rapid release of proinflammatory mediators and favor pathogen killing. However, recent findings on antigen presenting cells, particularly dendritic cells, revealed a more complex role for these molecules. Chronic exposure to low-dose nucleotides can redirect cellular responses to prototypic activation stimuli, leading to suppressed inflammation and immune deviation.  相似文献   
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