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71.
Zygomycosis or mucormycosis is an increasingly frequent life-threatening infection caused by opportunistic fungal organisms of the class Zygomycetes. The pathognomonic feature is the presence of invasive aseptate mycelia that are larger than other filamentous fungi with the hyphae exhibiting right angle and haphazard branching. Usually classified as rhinocerebral, disseminated, and cutaneous types, this classification serves as important predictor of pathogenesis and outcome. These occur mostly in immunosuppressed patients including individuals with diabetes (43% exhibit the rhino-cerebral form) and patients with organ transplants and hematologic malignancies. Without early aggressive treatment, the disease follows a dismal and fatal course. The prognosis has not shown any appreciable change in the past 40 years with a stagnant mortality rate of 44%. We present 2 cases of rhinocerebral zygomycosis (RCZ), in a 58-year-old male and a 63-year-old female; both were poorly controlled diabetic patients with maxillary lesions suggestive of osteomyelitis. The patients were leading a near normal life with minimal discomfort or signs and symptoms of underlying mycosis. Most of the health care professionals treating these patients often overlooked the disease or recommended inadequate therapy. Despite long delays and inadequate initial therapy these patients survived with little outward morbidity. The prognosis for this condition may therefore be considered less dire than previously thought.  相似文献   
72.

Purpose

Compared to low-grade disease, high-grade prostate cancers exhibit a higher rate of disease progression. As a result, there has been a trend to treat high-risk disease with methods other than surgery. The purpose of this study is to evaluate the long-term survival following radical prostatectomy (RRP) for non-metastatic Gleason 8–10 prostate adenocarcinoma (CaP).

Methods

All patients 75 years or less with Gleason 8–10 CaP that underwent RRP were identified from the SEER 18 database. Patients with metastatic disease, those who underwent other modalities of treatment, or with more than one primary cancer, were excluded. Data were analyzed for demographics, stage at presentation, treatment modality, and overall survival and cancer-specific survival.

Results

A total of 30,379 men met inclusion criteria. Mean age was 62.5 years and 82.5 % of patients were white. A total of 52.8 % of patients had T2 disease, and 73.1 % had node-negative disease, 80.2 % of patients underwent pelvic lymph node dissection, and 12.9 % underwent adjuvant radiation therapy. Overall survival for the entire cohort was 92.8, 78.6, 59.5, 38.6, and 20.0 % for 5, 10, 15, 20, and 25 years, respectively. Cancer-specific survival was 96.4, 89.5, 82.0, 72.9, and 68.8 % for 5, 10, 15, 20, and 25 years, respectively.

Conclusions

Although historically underutilized in patients with poorly differentiated disease, radical prostatectomy provides excellent long-term survival and should be offered to healthy patients.  相似文献   
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75.
Background and Purpose: Tenascin-C (TnC) is a multi-domain extracellular matrix glycoprotein that is expressed at a high level during embryogenesis but is almost absent during normal postnatal life. This multi-domain complex molecule is reported to associate with both pro-inflammatory and anti-inflammatory signalling cascades. In this study, we examined how TnC modulated intestinal inflammation.Experimental Approach: TnC pathophysiology was evaluated in cultures of rat intestinal subepithelial myofibroblasts (ISEMF) and intestinal epithelial cells. Wild-type and TnC(−/−) mice were treated with dextran sodium sulfate (DSS) to induce colitis.Key Results: DSS-induced colitis in mice markedly increased TnC in the damaged mucosal areas and up-regulated mRNA for TnC, pro-inflammatory cytokines and growth factors (PDGF-B and TGF-β1). In addition, 2,4,6-trinitrobenzene sulfonic acid-induced colitis and SAMP1/Yit mice, a model of spontaneous Crohn''s disease, also exhibited increased mucosal TnC in colon and ilea respectively. PDGF receptor-α (PDGFRα) positive ISEMF were the primary TnC-producing cells in colon tissues. Accordingly, ISEMF collected from the rat colon constitutively expressed both TnC and PDGFRα. PDGF-BB and TGF-β1 up-regulated both TnC mRNA and protein levels in ISEMF. Knock-down of TnC gene increased susceptibility to DSS-induced colitis, compared with TnC(+/+) littermates. TnC(−/−) mice showed marked abrasion of intestinal mucosal barrier and increased inflammatory scores. Moreover, TnC accelerated both trans-well migration and wound healing in epithelial cells.Conclusions and Implications: The pharmacological profiles of PDGF-BB and TGF-β in colitis tissues and ISEMF suggest that increased TnC production during inflammation contributed to epithelial cell migration, remodelling and protection of intestinal barriers.  相似文献   
76.
Silicene has become a topic of interest nowadays due to its potential application in various electro-mechanical nanodevices. In our previous work on silicene, fracture stresses of single crystal and polycrystalline silicene have been investigated. Existence of defects in the form of cracks reduces the fracture strength of silicene nanosheets to a great extent. In this study, an engineering way has been proposed for improving the fracture stress of silicene nanosheets with a pre-existing crack by incorporating auxiliary cracks symmetrically in a direction perpendicular to the main crack. We call this mechanism the “Failure shielding mechanism”. An extensive molecular dynamics simulation based analysis has been performed to capture the atomic level auxiliary crack-main crack interactions. It is found that the main crack tip stress distribution is significantly changed with the presence of auxiliary cracks for loading along both armchair and zigzag directions. The effects of temperature and the crack propagation speed of silicene have also been studied. Interestingly, in the case of loading along the zigzag direction, SW defect formation is observed at the tip of main crack. This leads to a reduction of the tip stress resulting in a more prominent failure shielding in case of zigzag loading than in armchair loading. Moreover, the position and length of the cracks as well as the loading directions have significant impacts on the tip stress distribution. Finally, this study opens the possibilities of strain engineering for silicene by proposing an engineering way to tailor the fracture strength of silicene.

Inclusion of auxiliary cracks increases the fracture stress of silicene nanosheets with a pre existing crack.  相似文献   
77.
The adsorptive removal of environmental pollutants is an effective method for the treatment of contaminated water. Thus, the preparation of adsorbents from low-cost, readily available, and renewable resources has garnered immense attention in recent years. In this study, a facile one-step method for the preparation of a high-capacity adsorbent is demonstrated by refluxing pine cones in concentrated sulfuric acid. With sulfuric acid reflux, the pine cones undergone carbonization as well as functionalization with sulfonic acid groups. The adsorbent demonstrated high adsorption capacity for two emerging organic pollutants, methylene blue (MB) and tetracycline (TC). Different variables such as pH, temperature, contact time, and initial concentration of the pollutants were analyzed and showed that the adsorption capacity for MB increased in a basic pH and vice versa for TC. Also, the elevated temperature favored the adsorption for both MB and TC. The maximum adsorption capacity was found to be 1666.66, and 357.14 mg g−1 for MB and TC, respectively. In comparison to the pristine pine cone, the sulfuric acid treated pine cone demonstrated an extraordinary improvement in the adsorption capacity. The adsorption of MB and TC was performed from the tap water matrix and similar adsorption capacities were found. A packed glass column was also prepared to demonstrate the adsorption of MB from tap water under flow conditions.

Facile conversion of pine cones into a high-capacity adsorbent for the removal of methylene blue and tetracycline from water.  相似文献   
78.
Optimal transportation of bacteria is important for accurate clinical interpretation, quantitative assays, and microbiome studies. A transport medium should ideally keep the bacteria alive without supporting growth or altering the relative proportions of the constituent species. We investigated the effect of nasal mucus and mucin on the growth and survival of two Staphylococcus aureus strains in liquid Amies transport medium at room temperature and 4?°C for 14?days. The study showed that the presence of nasal mucus in microbiological samples stimulated undesired S. aureus growth at room temperature in a dose-dependent manner. These findings underscore that microbiological samples from humans and animals should be stored at 4?°C until analysis to avoid undesired S. aureus growth.  相似文献   
79.
A new metabolite of arachidonic acid, formed during interaction between thrombin- or collagen-stimulated platelets and unstimulated neutrophils, has been demonstrated by both thin-layer radiochromatography and high-performance liquid chromatography. Production of the 3H-labeled metabolite in combined suspensions containing [3H]arachidonate-labeled platelets and unlabeled neutrophils from aspirin-treated donors suggested that platelet 3H-labeled 12S-hydroxy-5,8-cis,10-trans,14-cis-icosatetraenoic acid (12-HETE) was the precursor. This was confirmed by identification of the same product when purified 12-[3H]HETE was added directly to unstimulated neutrophils. Hydrogenation and oxidation of the isolated product, followed by gas chromatography-mass spectrometry showed the structure to be 12S,20-dihydroxyicosatetraenoic acid. These experiments further show that platelet stimuli known to occur in vivo may initiate metabolic interactions between different cell types via the arachidonic acid pathway.  相似文献   
80.
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