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101.
Background  Alopecia areata (AA) is an immune-mediated form of hair loss that occurs in all ethnic groups, ages, and both sexes. Helicobacter pylori has been associated with certain extra-digestive dermatological conditions, including chronic urticaria, rosacea, Schönlein-Henoch purpura, Sweet syndrome, systemic sclerosis, and atopic dermatitis.
Objective  The causal relation between alopecia areata and H. pylori is discussed. We have screened for the presence of H. pylori in patients with AA in order to determine any potential role in its pathophysiology.
Patients and methods  We have prospectively studied 31 patients with AA and 24 healthy volunteers of similar gender for the presence of H. pylori surface antigen (HpSag) in stool.
Results  Optical density values for H. pylori infection were positive in 18 of all 31 patients evaluated (58.1%), while in 13 patients, values did not support H. pylori infection (41.9%). While in the control group, 10 of 24 (41.7%) had positive results. Within the group of AA, there was no significant difference between HpSag-positive and HpSag-negative patients.
Conclusions  Based on these results, the relation between H. pylori and AA is not supported. We advise that H. pylori detection should not be included in the laboratory workup of AA.  相似文献   
102.
103.
Metastases from bladder cancer to the bones of the hands or feet are rare and usually present after the diagnosis of the primary lesion has been made. This case report describes a 76-year-old man presenting with initial signs of infection of the right foot. Subsequent bone scan revealed multiple bony metastases and hydronephrosis raising the possibility of a primary bladder tumour that was later confirmed by urine cytology and fine needle aspiration of the foot.  相似文献   
104.
105.
BACKGROUND: Eosinophils are frequently associated with tissue remodeling and fibrosis in allergic and other diseases and animal models. Their close physical proximity to fibroblasts at sites of tissue remodeling strongly implicates them in fibrogenesis, including subepithelial fibrosis and airway remodeling characteristic of asthma. OBJECTIVE: To identify the mediators and characterize the mechanisms underlying the fibrogenic activities of eosinophils. METHODS: A coculture system of blood eosinophils or eosinophil cell lines with normal fibroblasts was used to assess their ability to induce a fibrogenic fibroblast phenotype, including IL-6 secretion and mRNA expression, and induction of genes involved in extracellular matrix production and homeostasis. The mediators of these responses were identified by using transwell barrier cocultures, eosinophil-conditioned media, and cytokine-specific antibody neutralization. RESULTS: Eosinophil-fibroblast coculture induced potent fibroblast IL-6 secretion and mRNA expression, responses further enhanced by IL-5. The soluble nature of the eosinophil-derived mediators was demonstrated by using eosinophil-fibroblast coculture in the presence of permeable transwell barriers, and fibroblast culture in eosinophil-conditioned media, indicating that cell contact was not required. Induction of fibroblast IL-6 expression was accompanied by increased expression of fibronectin and the extracellular matrix regulatory genes plasminogen activator inhibitor 1 and tissue inhibitor of metalloproteinase 1. Antibody neutralization identified the principal eosinophil-derived mediator of fibroblast IL-6 expression as IL-1beta (>60%), with lesser contributions from IL-1alpha, IL-4, and TGF-beta (10% to 20%). CONCLUSION: Eosinophils express at least 2 potent mediators (IL-1beta and TGF-beta) that induce a fibrogenic fibroblast phenotype, strongly supporting a role for the eosinophil in the dysregulation of extracellular matrix homeostasis and consequent tissue remodeling and fibrosis in eosinophil-associated diseases.  相似文献   
106.
We describe a case of Gemella bergeriae endocarditis in a patient with a bicuspid aortic valve. Diagnosis was confirmed by sequencing of 16S rRNA genes in heart valve tissue. This is the first report of Gemella endocarditis confirmed by molecular detection of bacterial genes in heart valve tissue.  相似文献   
107.
Current applications of the microencapsulation technique include the use of encapsulated islet cells to treat Type 1 diabetes, and encapsulated hepatocytes for providing temporary but adequate metabolic support to allow spontaneous liver regeneration, or as a bridge to liver transplantation for patients with chronic liver disease. Also, microcapsules can be used for controlled delivery of therapeutic drugs. The two most widely used devices for microencapsulation are the air-syringe pump droplet generator and the electrostatic bead generator, each of which is fitted with a single needle through which droplets of cells suspended in alginate solution are produced and cross-linked into microbeads. A major drawback in the design of these instruments is that they are incapable of producing sufficient numbers of microcapsules in a short-time period to permit mass production of encapsulated and viable cells for transplantation in large animals and humans. We present in this paper a microfluidic approach to scaling up cell and protein encapsulations. The microfluidic chip consists of a 3D air supply and multi-nozzle outlet for microcapsule generation. It has one alginate inlet and one compressed air intlet. The outlet has 8 nozzles, each having 380 micrometers inner diameter, which produce hydrogel microspheres ranging from 500 to 700 μm in diameter. These nozzles are concentrically surrounded by air nozzles with 2 mm inner diameter. There are two tubes connected at the top to allow the air to escape as the alginate solution fills up the chamber. A variable flow pump 115 V is used to pump alginate solution and Tygon? tubing is used to connect in-house air supply to the air channel and peristaltic/syringe pump to the alginate chamber. A pressure regulator is used to control the flow rate of air. We have encapsulated islets and proteins with this high throughput device, which is expected to improve product quality control in microencapsulation of cells, and hence the outcome of their transplantation.  相似文献   
108.
Although polymeric nanoparticles/microparticles are well established for the mucosal administration of conventional drugs, they have not yet been developed commercially for vaccine delivery. The limitation of the mucosal (particularly oral) route of delivery, including low pH, gastric enzymes, rapid transit and poor absorption of large molecules, has made mucosal vaccine delivery challenging. Nevertheless, several polymeric delivery systems for mucosal vaccine delivery are currently being evaluated. The polymer-based approaches are designed to protect the antigen in the gut, to target the antigen to the gut-associated lymphoid tissue or to increase the residence time of the antigen in the gut through bioadhesion. M-cell targeting is a potential approach for mucosal vaccine delivery, which can be achieved using M-cell-specific lectins, microbial adhesins or immunoglobulins. While many hurdles must be overcome before targeted mucosal vaccine delivery becomes a practical reality, this is a potential area of research that has important implications for future vaccine development. This review comprises various aspects that could be decisive in the development of polymer based mucosal vaccine delivery systems.  相似文献   
109.
The intensive care unit (ICU) is an instance of a very dynamic health care setting where critically ill patients are being managed. To provide good care, an extensive and coordinated communication amongst the role players, use of numerous information systems and operation of devices for monitoring and treatment purposes are required. The purpose of this research is to study error evolution and management within this environment. The focus is on representing the workflow of critical care environment, which emphasizes the importance such a representation may play in strategizing the management of medical errors. We used ethnographic observation and interview data to build individual pieces of the workflow, dependent on the individual and the activity concerned. Key personnel were intensively followed during their respective patient care activities and the related actions. All interactions were recorded for analysis. These clinicians and nurses were interviewed to complement the observation data and to delineate their individual workflows. These pieces of the ICU workflow were used to develop a generalize-able cognitive model to represent the intricate workflow applicable to other health care settings. The proposed model can be used to identify and characterize medical errors and for error prediction in practice.  相似文献   
110.
Phagocytic responses are critical for effective host defense against opportunistic fungal pathogens. Macrophages sample the phagosomal content and orchestrate the innate immune response. Toll-like receptor 9 (TLR9) recognizes unmethylated CpG DNA and is activated by fungal DNA. Here we demonstrate that specific triggering of TLR9 recruitment to the macrophage phagosomal membrane is a conserved feature of fungi of distinct phylogenetic origins, including Candida albicans, Saccharomyces cerevisiae, Malassezia furfur, and Cryptococcus neoformans. The capacity to trigger phagosomal TLR9 recruitment was not affected by a loss of fungal viability or cell wall integrity. TLR9 deficiency has been linked to increased resistance to murine candidiasis and to restriction of fungal growth in vivo. Macrophages lacking TLR9 demonstrate a comparable capacity for phagocytosis and normal phagosomal maturation compared to wild-type macrophages. We now show that TLR9 deficiency increases macrophage tumor necrosis factor alpha (TNF-α) production in response to C. albicans and S. cerevisiae, independent of yeast viability. The increase in TNF-α production was reversible by functional complementation of the TLR9 gene, confirming that TLR9 was responsible for negative modulation of the cytokine response. Consistently, TLR9 deficiency enhanced the macrophage effector response by increasing macrophage nitric oxide production. Moreover, microbicidal activity against C. albicans and S. cerevisiae was more efficient in TLR9 knockout (TLR9KO) macrophages than in wild-type macrophages. In conclusion, our data demonstrate that TLR9 is compartmentalized selectively to fungal phagosomes and negatively modulates macrophage antifungal effector functions. Our data support a model in which orchestration of antifungal innate immunity involves a complex interplay of fungal ligand combinations, host cell machinery rearrangements, and TLR cooperation and antagonism.  相似文献   
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