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961.

Introduction

Papillary tumors of the pineal region (PTPR) are rare brain tumors characterized by frequent local recurrences. Standardized treatment strategies are not yet defined.

Case report

We present the case of a 3-year-old girl diagnosed with PTPR. Due to her young age, adjuvant radiotherapy was omitted after gross total tumor resection. Thirty-six months later, local tumor recurrence occurred. Considering the possible risks of secondary surgery, the recurrent tumor was irradiated with proton radiotherapy. Three months later, the tumor showed near-complete remission.

Discussion

Based on this experience and other pediatric case reports from the literature, local radiotherapy might be suggested also after complete tumor resection.  相似文献   
962.
This study evaluated the prothrombin time (PT) assay for the measurement of plasma concentrations of rivaroxaban using calibrators and controls. The intra- and interlaboratory precision of the measurement was investigated in a field trial involving 21 laboratories. Each laboratory was provided with rivaroxaban calibrators and control plasma samples containing different concentrations of rivaroxaban, and PT reagents. The evaluation was carried out over 2 consecutive weeks using centrally provided and local PT reagents. A calibration curve was produced each day (for inter-run precision), and day-to-day precision was evaluated by testing 3 control plasma samples. A large interlaboratory variation (in seconds) was observed with local PT reagents. The results were less variable when expressed as rivaroxaban concentrations (ng/mL) or when central PT reagent was used (STA Neoplastine CI Plus). The widely available PT assay, in conjunction with rivaroxaban calibrators, may be useful for the measurement of peak plasma levels of rivaroxaban.  相似文献   
963.
Duchenne muscular dystrophy (DMD) is the most frequent muscular dystrophy in children and young adults. Currently, there is no cure for the disease. The transplantation of healthy myoblasts is an experimental therapeutic strategy, since it could restore the expression of dystrophin in DMD muscles. Nevertheless, this cellular therapy is limited by immune reaction, low migration of the implanted cells, and high early cell death that could be at least partially due to anoikis. To avoid the lack of attachment of the cells to an extracellular matrix after the transplantation, which is the cause of anoikis, we tested the use of a fibrin gel for myoblast transplantation. In vitro, three concentrations of fibrinogen were compared (3, 20, and 50 mg/ml) to form a fibrin gel. A stiffer fibrin gel leads to less degradability and less proliferation of the cells. A concentration of 3 mg/ml fibrin gel enhanced the differentiation of the myoblasts earlier as a culture in monolayer. Human myoblasts were also transplanted in muscles of Rag/mdx mice in a fibrin gel or in a saline solution (control). The use of 3 mg/ml fibrin gel for cell transplantation increased not only the survival of the cells as measured after 5 days but also the number of fibers expressing dystrophin after 21 days, compared to the control. Moreover, the fibrin gel was also compared to a prosurvival cocktail. The survival of the myoblasts at 5 days was increased in both conditions compared to the control but the efficacy of the prosurvival cocktail was not significantly higher than the fibrin gel.  相似文献   
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Chronic pain syndromes (CPS) are highly prevalent in the general population, and increasingly the evidence points to a common etiological pathway. Using a large cohort of twins (n = 8564) characterized for chronic widespread musculoskeletal pain (CWP), chronic pelvic pain (PP), migraine (MIG), dry eye disease, and irritable bowel syndrome (IBS), we explored the underlying genetic and environmental factors contributing to CPS and the correlation between them. The sample was predominantly female (87.3%), with a mean age of 54.7 (±14.7) years. Prevalence of the different CPS ranged from 7.4% (PP) to 15.7% (MIG). For all CPS the within-twin correlation in monozygotic twin pairs was higher than in dizygotic pairs, suggesting a heritable component. Estimated heritability ranged from 19% (IBS) to 46% (PP). Except for MIG, we found significant pairwise phenotypic correlations between the CPS. The phenotypic correlation was highest between CWP and IBS (0.40; 95% confidence interval: 0.27 to 0.46). Excluding MIG from further analyses, cross-twin cross-trait correlations were higher in monozygotic compared with dizygotic twin pairs, suggestive of shared genetic factors between CWP, PP, IBS, and dry eye disease. Twin modeling analysis revealed the common pathway model as the model best explaining the observed pattern of correlation between the traits, with an estimated heritability of 66% of the underlying latent variable. These results are evidence of shared genetic factors in conditions manifesting chronic pain and justify the search for underlying genetic variants.  相似文献   
967.

Aims/hypothesis

Microangiopathy is a leading complication of diabetes that commonly affects the retina. Degenerate capillaries are a central feature of diabetic retinopathy. An inflammatory process has been linked to the development of diabetic retinopathy but its regulation is incompletely understood. Cluster of differentiation (CD) 40 is a member of the TNF receptor superfamily that promotes the development of certain inflammatory disorders. The role of CD40 in diabetic microangiopathy is unknown.

Methods

B6 and Cd40 ?/? mice were administered streptozotocin to induce diabetes. Leucostasis was assessed using fluorescein isothiocyanate-conjugated concanavalin A. Retinal Icam1 and Cd40 mRNA levels were examined using real-time PCR. Protein nitration was assessed by immunohistochemistry. Histopathology was examined in the retinal vasculature. CD40 expression was assessed by flow cytometry and immunohistochemistry. Intercellular adhesion molecule 1 (ICAM-1) and nitric oxide synthase 2 (NOS2) were examined by immunoblot and/or flow cytometry. Nitric oxide production was examined by immunoblot and Griess reaction.

Results

In mouse models of diabetes, Cd40 ?/? mice exhibited reduced retinal leucostasis and did not develop capillary degeneration in comparison with B6 mice. Diabetic Cd40 ?/? mice had diminished ICAM-1 upregulation and decreased protein nitration. Cd40 mRNA levels were increased in the retinas of diabetic B6 mice compared with non-diabetic controls. CD40 expression increased in retinal Müller cells, endothelial cells and microglia of diabetic animals. CD40 stimulation upregulated ICAM-1 in retinal endothelial cells and Müller cells. CD40 ligation upregulated NOS2 and nitric oxide production by Müller cells.

Conclusions/interpretation

CD40-deficient mice were protected from the development of diabetic retinopathy. These mice exhibited diminished inflammatory responses linked to diabetic retinopathy. CD40 stimulation of retinal cells triggered these pro-inflammatory responses.  相似文献   
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Awareness of the health risks of smoking is an important factor in predicting smoking-related behaviour; however, little is known about the knowledge of health risks in low-income countries such as India. The present study examined beliefs about the harms of smoking and the impact of health knowledge on intentions to quit among a sample of 249 current smokers in both urban and rural areas in two states (Maharashtra and Bihar) from the 2006 TCP India Pilot Survey, conducted by the ITC Project. The overall awareness among smokers in India of the specific health risks of smoking was very low compared to other ITC countries, and only 10% of respondents reported that they had plans to quit in the next six months. In addition, smokers with higher knowledge were significantly more likely to have plans to quit smoking. For example, 26.2% of respondents who believed that smoking cause CHD and only 5.5% who did not believe that smoking causes CHD had intentions to quit (χ2 = 16.348, p < 0.001). Important differences were also found according to socioeconomic factors and state: higher levels of knowledge were found in Maharashtra than in Bihar, in urban compared to rural areas, among males, and among smokers with higher education. These findings highlight the need to increase awareness about the health risks of smoking in India, particularly in rural areas, where levels of education and health knowledge are lower.  相似文献   
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