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Radiation-induced breast angiosarcoma, or secondary angiosarcoma (SAS), is a rare entity with a high risk of metastatic recurrence. Herein, we describe the use of intraoperative fluorescence-based skin angiography to guide surgical resection following a novel immunotherapy-based regimen for SAS resulting in a complete pathological response.  相似文献   
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Nerve growth factor (NGF) regulates the survival and development of specific populations of neurones and is involved in wound healing. A further area of study relating to the role of neurotrophins in the mature animal has concerned the possibility that NGF may be a pivotal mediator of inflammation and pain. It has previously been shown that injection of intradermal NGF can result in a neutrophil-dependent hyperalgesia in the rat. The purpose of the present study was to examine the pathological consequence of NGF injected intradermally into mature rat skin and to examine further the role of neutrophils. Standard histopathology techniques (H & E) were employed to determine inflammatory cell counts. Circulating neutrophils were depleted using an anti-rat neutrophil antiserum and results were compared to treatment with vehicle controls. Saline-pretreated rats exhibited normal circulating neutrophil numbers and the dorsal skin showed a significant increase of neutrophil and macrophages at 3 and 5 h and lymphocytes at 5 h after NGF treatment. By comparison, skin sites from neutrophil-depleted rats did not demonstrate a significant increase in neutrophil and macrophage accumulation after NGF administration. All NGF-treated sites, independent of pretreatment, demonstrated abnormal muscle fibre morphology and proliferation of the muscle sarcolemmal nuclei after NGF injection, indicative of tissue injury. In addition, oedema and some fibroplasia were also noted. Furthermore, fibrin production was increased at 3 and 5 h after NGF administration. It is suggested that NGF has a damaging effect on rat muscle which is independent of accumulating neutrophil and other inflammatory cells. In conclusion, the findings indicate a link between NGF-induced neutrophil and macrophage accumulation, as the increase in dermal macrophages was not observed in neutrophil-depleted rats. The results also suggest that NGF can have a profound effect on rat muscle and that this effect may be related to muscle regeneration.  相似文献   
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Conventional psychometric measures uniformly yield zero or near zero scores (i.e., "bottom-out") as patients with Alzheimer's disease (AD) progress to the more severe stages of the illness. Consequently, there are no psychometric measures which objectively assess the mental abilities of AD patients with very severe cognitive impairment. We explored the hypothesis that mental function in AD patients with very severe cognitive impairment can be effectively assessed using test measures developed to assess the earliest stage of cognitive development as proposed by Piaget. We also investigated the relationship between decline on these experimental cognitive measures and progressive functional disability in patients with severe cognitive impairment. The results indicate that modified instruments derived from measures developed to assess Piaget's sensorimotor stage of cognitive development provide useful information about the cognitive abilities of very severely impaired AD patients. These modified instruments provide a measure of cognition in these extremely impaired patients that has acceptable validity and demonstrable reliability.  相似文献   
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Background: Thymusderived lymphocytes play a critical role in the development of herpes simplex keratitis (HSK). T-cell subsets defined by their expression of various T-cell receptor (TCR) Vß segments were studied following corneal HSV-1 infection (p.i.). Methods: Conjunctiva, corneal limbus and corneal stroma of two inbred BALB/c congenic mouse strains which differ only in the gene products closely linked to the Igh-1 locus on chromosome 12 were analyzed. Results: While C.B-17 mice (Igh-1b) were resistant to HSK, C.AL-20 mice (Igh-1d) clinically developed severe necrotizing keratitis by day 11 p.i. The corneal stroma of C.B-17 mice remained clear, while it was increasingly infiltrated by mononuclear cells and neutrophils in C.AL-20 mice by day 11 p.i. In C.B-17 mice, Thy1.2+ cells were found in the conjunctiva between days 2 to 4 p.i., and subsequently decreased. Only a few Thyl.2+ cells were found in the limbus, and no such cells were found in the stroma. In contrast, in C.AL-20 mice the numbers of Thyl.2+ cells (activated CD4+, Vß8+ T cells) profoundly increased in the conjunctiva by day 4 p.i. These cells infiltrated the limbus between days 7 and 11 p.i. and eventually entered the stromal tissue by day 11 p.i. Conclusions: Our data suggest that the HSV-1-induced corneal tissue destruction is mediated by mononuclear cells and neutrophils and that these cells are probably attracted into the cornea by cytokines elaborated by activated CD4+, Vß8+ T cells.Presented as a paper at the ECORA Meeting, 4–7 October 1993, Bonn  相似文献   
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Poly(lactide-co-glycolide) microspheres containing different loads of OVA (0.05, 0.1, 0.5 and 1.0% w/w) were manufactured by a w/o/w emulsion/solvent evaporation method. Low load efficiencies of less than 20% were observed. Normal size distributions with mean volume diameters ranging from 3.7 to 4.7 µm were obtained for different batches. The in vitro release of OVA from different loaded microspheres showed an expected burst release with all batches. The in vivo dose study (1, 10, 25, 50 µg of OVA) was performed by subcutaneous and oral inoculation in mice by single (0 week) or double (0 and 3 weeks) administration of PLGA 50/50 microspheres containing 0.1% OVA. Subcutaneous administration showed an immune response (serum Ig levels by ELISA) statistically (Fishers paired t-test; P < 0.05) above OVA saline negative controls at 3, 6 and 12 weeks after administration. Oral administration of microspheres produced statistically higher systemic immune responses at the higher doses. Single and double inoculation orally and subcutaneously produced similar serum antibody levels. The in vivo load study was performed by subcutaneous and oral administration to mice of 25 µg OVA contained in various loaded (0.05, 0.1, 0.5 and 1.0% w/w) microspheres. Serum immune responses at 3, 6, and 12 weeks after inoculation were statistically above OVA saline controls and were inversely proportional to the OVA load using either route. This observation suggested a relationship between the number of microspheres delivered and the in vivo serum response. Single subcutaneous administration of 0.05 or 0.1% OVA loaded PLGA 50/50 microspheres induced larger immune responses compared with complete Freunds adjuvant.  相似文献   
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PURPOSE: To determine and compare the diagnostic performance of fetal middle cerebral (MCA), renal (RA), and umbilical (UA) arterial Doppler ultrasonography (US) for prediction of adverse perinatal outcome in suspected intrauterine growth restriction (IUGR). MATERIALS AND METHODS: Two hundred ninety-three small-for-gestational age fetuses (24-39 weeks at recruitment and US-estimated weight or abdominal circumference below 10th percentile) were prospectively examined with Doppler US of the UA, MCA, and RA. Clinicians were blinded to MCA and RA Doppler measurements. RESULTS: Seventy-six fetuses (25.9%) had at least one major or minor adverse perinatal outcome. Major outcomes included stillbirth, neonatal death, neurologic complication, and necrotizing enterocolitis. The MCA pulsatility index (PI), compared with the UA PI and RA PI, was more sensitive (72.4% vs 44.7% and 8.3%) but less specific (58.1% vs 86.6% and 92.6%) in predicting adverse outcome. The UA PI had the highest positive likelihood ratio (ratio, 3.3); the MCA PI had the lowest negative likelihood ratio (ratio, 0.48). When gestational age at the first Doppler US examination was less than 32 weeks, the MCA PI had a sensitivity of 95.5% and negative predictive value of 97.7% for major adverse outcome (negative likelihood ratio, 0.10). CONCLUSION: In suspected IUGR, while an abnormal UA PI is a better predictor of adverse perinatal outcome than an abnormal MCA or RA PI, a normal MCA PI may help to identify fetuses without major adverse perinatal outcome, especially before 32 weeks gestational age.  相似文献   
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