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91.
Patients with essential thrombocythemia (ET) often suffer from neurological symptoms (NS) not ever resulting from previous thrombotic cerebral events (TCE). We reported NS occurred in 282 patients, in order to identify the factors influencing ET‐related NS in the absence of TCE, and the response to therapy. Overall, 116 of 282 patients (41%) presented NS; 101 of them (87%) reported subjective transient and fluctuating NS, without concurrent TCE, which we defined as ET‐related NS, by frequency: cephalalgia, chronic paresthesias, dizziness or hypotension, visual disturbances, and tinnitus. In univariate analysis, ET‐related NS resulted more frequently in young people (P = 0.017) and in females (P = 0.025). We found a higher prevalence of JAK2V617F mutation in ET‐related NS patients (P = 0.021). In multivariate analysis, gender (P = 0.024) and JAK2V617F mutation (P = 0.041) remained significantly associated with the development of ET‐related NS, with a risk of about four times higher for JAK2V617F‐mutated patients (OR = 3.75). Ninety‐seven of 101 patients with ET‐related NS received an antiplatelet (AP) agent at the time of NS, whereas only selected high‐risk ET‐related NS patients were treated with a cytoreductive drug, according to the published guidelines and similarly to patients without NS. We observed that only 32 of 97 (33%) patients with ET‐related NS achieved a complete response after AP treatment. Among the 65 non‐responder patients, 36 (55.4%) improved NS after the introduction of cytoreductive therapy; therefore, the addition of cytoreductive treatment should be considered in this setting.  相似文献   
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Aspergillus spp. are among the most common causes of opportunistic invasive fungal infections in tertiary care hospitals. Little is known about the prevalence and in vitro susceptibility of Aspergillus species in Latin America, because there are few medical centers able to perform accurate identification at the species level. The purpose of this study was to analyze the distribution of cryptic and rare Aspergillus species among clinical samples from 133 patients with suspected aspergillosis admitted in 12 medical centers in Brazil and to analyze the in vitro activity of different antifungal drugs. The identification of Aspergillus species was performed based on a polyphasic approach, as well as sequencing analysis of the internal transcribed spacer (ITS) region, calmodulin, and β-tubulin genes and phylogenetic analysis when necessary. The in vitro susceptibility tests with voriconazole, posaconazole, and itraconazole were performed according to the CLSI M38-A2 document (2008). We demonstrated a high prevalence of cryptic species causing human infection. Only three isolates, representing the species Aspergillus thermomutatus, A. ochraceus, and A. calidoustus, showed less in vitro susceptibility to at least one of the triazoles tested. Accurate identifications of Aspergillus at the species level and with in vitro susceptibility tests are important because some species may present unique resistance patterns against specific antifungal drugs.  相似文献   
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A new effective surgical procedure to repair chronic ulcers called minced micrografts technique has been recently reported. The technique consists in spreading a finely minced skin sample upon the wound bed. In this study, we investigate the in vitro release of cytokines (interleukin‐6, tumor necrosis factor‐α, interleukin‐1α, and granulocyte‐colony stimulating factor), chemokines (monocyte chemoattractant protein‐1 and growth‐related oncogene‐α), and growth factors (platelet‐derived growth factor, basic fibroblast growth factor, vascular endothelial growth factor, hepatocyte growth factor, and nerve growth factor) by minced (referred to as the minced sample) vs. not minced (referred to as the whole sample) human skin biopsy samples from the same donor. Factor release in the culture medium at different time points was detected using a multiplexed protein assay. The minced sample, which could behave like the skin fragments used in vivo in the autologous minced micrografts technique, expressed higher levels of tumor necrosis factor‐α, interleukin‐1α, platelet‐derived growth factor, and basic fibroblast growth factor, and lower levels of interleukin‐6, monocyte chemoattractant protein‐1, growth related oncogene‐α, and vascular endothelial growth factor compared with the whole sample. In conclusion, mincing of healthy skin may allow appropriate regulation of the inflammatory phase of wound healing and could induce overexpression of some growth factors, which facilitates the proliferative phase of healing.  相似文献   
95.
Despite recent therapeutic advances, multiple myeloma (MM) is still an incurable neoplasia due to intrinsic or acquired resistance to therapy. Myeloma cell localization in the bone marrow milieu allows direct interactions between tumor cells and non-tumor bone marrow cells which promote neoplastic cell growth, survival, bone disease, acquisition of drug resistance and consequent relapse. Twenty percent of MM patients are at high-risk of treatment failure as defined by tumor markers or presentation as plasma cell leukemia. Cumulative evidences indicate a key role of Notch signaling in multiple myeloma onset and progression. Unlike other Notch-related malignancies, where the majority of patients carry gain-of-function mutations in Notch pathway members, in MM cell Notch signaling is aberrantly activated due to an increased expression of Notch receptors and ligands; notably, this also results in the activation of Notch signaling in surrounding stromal cells which contributes to myeloma cell proliferation, survival and migration, as well as to bone disease and intrinsic and acquired pharmacological resistance. Here we review the last findings on the mechanisms and the effects of Notch signaling dysregulation in MM and provide a rationale for a therapeutic strategy aiming at inhibiting Notch signaling, along with a complete overview on the currently available Notch-directed approaches.  相似文献   
96.
Morphometric MRI studies in adult patients with migraine have consistently demonstrated atrophy of several gray matter (GM) regions involved in pain processing. We explored the regional distribution of GM and white matter (WM) abnormalities in pediatric patients with episodic migraine and their correlations with disease clinical manifestations. Using a 3.0 T scanner, brain T2-weighted and 3D T1-weighted scans were acquired from 12 pediatric migraine patients and 15 age-matched healthy controls. GM and WM volumetric abnormalities were estimated using voxel-based morphometry (p < 0.05, family-wise error corrected). Compared to controls, pediatric migraine patients experienced a significant GM atrophy of several regions of the frontal and temporal lobes which are part of the pain-processing network. They also had an increased volume of the right putamen. The left fusiform gyrus had an increased volume in patients with aura compared to patients without aura and controls, whereas it was significantly atrophied in patients without aura when compared to the other two groups. No abnormalities of WM volume were detected. In migraine patients, regional GM atrophy was not correlated with disease duration and attack frequency, whereas a negative correlation was found between increased volume of the putamen and disease duration (r = ?0.95, p < 0.05). These results show that GM morphometric abnormalities do occur in pediatric patients with migraine. The presence of such abnormalities early in the disease course, and the absence of correlation with patient clinical characteristics suggest that they may represent a phenotypic biomarker of this condition.  相似文献   
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Dysregulated tonic pupil size has been reported in autism spectrum disorder (ASD). Among the possible sources of this dysregulation are disruptions in the feedback loop between norepinephrine (NE) and hypothalamic systems. In the current study, we examined afternoon levels of salivary alpha‐amylase (sAA, a putative correlate of NE) and cortisol (used to assess stress‐based responses) in two independent samples of children with ASD. We found a larger pupil size and lower sAA levels in ASD, compared to typical and clinical age‐matched controls. This was substantiated at the individual level, as sAA levels were strongly correlated with tonic pupil size. Relatively little diurnal variation in sAA taken in the home environment in the ASD group was also observed, while typical controls showed a significant linear increase throughout the day. Results are discussed in terms of potential early biomarkers and the elucidation of underlying neural dysfunction in ASD. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 465–482, 2013  相似文献   
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