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Twelve patients in whom radial artery infections developed after catheterization in an intensive care unit over a 2-year period were reviewed. The incidence of local infection was 0.4%. An increased risk of infection was associated with prolonged catheterization (greater than 4 days). Aneurysms developed in five patients. Signs of septic emboli were present in two patients, including Osler's nodes, Janeway's lesions, and fingertip infarcts. In 6 of the 12 patients, the radial artery infection resolved with antibiotic treatment alone. The five patients with infected aneurysms were treated successfully with antibiotics and surgical excision. The radial artery was reconstructed by use of a vein graft in one patient. We believe that patients not responding promptly to antibiotics or patients with infected aneurysms are best treated by surgical excision.  相似文献   
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1. The effect of in vivo desensitization to leukotriene B4 (LTB4) on eosinophil infiltration in response to recombinant C5a was examined in guinea-pig skin. 2. LTB4 (10-300 ng) and C5a (1-10 micrograms) caused a dose-dependent increase in the levels of eosinophil peroxidase activity (a measure of eosinophil infiltration) 4 h after injection into guinea-pig skin. Leukotriene B4 and C5a were approximately equipotent on a molar basis. Platelet activating factor (0.01-10 micrograms) also caused eosinophil accumulation but was much less active than LTB4 or C5a. 3. 20-Hydroxy-LTB4 caused a dose-dependent desensitization of eosinophil responses to LTB4 (ED50 = 1.6 micrograms kg-1, s.c.) and partially reduced responses to C5a. At a dose of 20-hydroxy-LTB4 (10 micrograms) which inhibited responses to LTB4 completely, responses to C5a were reduced by 56.5 +/- 1.8% (n = 5). The structurally related metabolite of 20-hydroxy-LTB4, 20-carboxy-LTB4, which does not cause desensitization to the effects of LTB4, did not inhibit eosinophil infiltration in response to C5a. 4. The LTB4 receptor antagonist, SC-41,930 (10 mg kg-1, p.o.), also inhibited eosinophil accumulation in response to C5a by 63.0 +/- 3.9% (n = 5) at a dose which inhibited responses to LTB4 by 86.5 +/- 1.9% (n = 5). 5. These data indicate that eosinophil infiltration in response to C5a may, in part, be mediated by the generation of secondary chemotactic factors such as LTB4.  相似文献   
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OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs.  相似文献   
5.
A 7-cm anterior mediastinal tumor in an 80-year-old woman was found by light and electron microscopy to be a neuroblastoma. Immunoreactivity for neuron-specific enolase, synaptophysin, and chromogranin supported the diagnosis. Neuroblastoma is an uncommon tumor in adults and we are not aware of a previous report of such a tumor in a patient of this age.  相似文献   
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This article describes a specialized rehabilitation education program, based on adult learning theory, that was developed to promote retention of rehabilitation nurses at MetroHealth Center for Rehabilitation in Cleveland. The curriculum encompasses the skills required to care for rehabilitation patients needing both advanced rehabilitation nursing and critical care nursing. Critical care and rehabilitation nurses collaborated in the presentation of topics and were guided by the course coordinators. Learners were chosen based on experience in rehabilitation, with priority given to those certified in rehabilitation nursing. A variety of evaluation methods elicited positive responses. A 6-month postcourse survey also was completed to assess the long-term effects of the course.  相似文献   
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BACKGROUND: Formation of long-term memories is critically dependent on extracellular-regulated kinase (ERK) signaling. Activation of the ERK pathway by the sequential recruitment of mitogen-activated protein kinases is well understood. In contrast, the proteins that inactivate this pathway are not as well characterized. METHODS: Here we tested the hypothesis that the brain-specific striatal-enriched protein tyrosine phosphatase (STEP) plays a key role in neuroplasticity and fear memory formation by its ability to regulate ERK1/2 activation. RESULTS: STEP co-localizes with the ERKs within neurons of the lateral amygdala. A substrate-trapping STEP protein binds to the ERKs and prevents their nuclear translocation after glutamate stimulation in primary cell cultures. Administration of TAT-STEP into the lateral amygdala (LA) disrupts long-term potentiation (LTP) and selectively disrupts fear memory consolidation. Fear conditioning induces a biphasic activation of ERK1/2 in the LA with an initial activation within 5 minutes of training, a return to baseline levels by 15 minutes, and an increase again at 1 hour. In addition, fear conditioning results in the de novo translation of STEP. Inhibitors of ERK1/2 activation or of protein translation block the synthesis of STEP within the LA after fear conditioning. CONCLUSIONS: Together, these data imply a role for STEP in experience-dependent plasticity and suggest that STEP modulates the activation of ERK1/2 during amygdala-dependent memory formation. The regulation of emotional memory by modulating STEP activity may represent a target for the treatment of psychiatric disorders such as posttraumatic stress disorder (PTSD), panic, and anxiety disorders.  相似文献   
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(+)-Catechin inhibited the copper-catalysed oxidation of human low density lipoprotein (LDL) in a dose-dependent manner with complete inhibition at 20 micrograms/mL. The flavonoid at a concentration of 50 micrograms/mL also inhibited oxidation of LDL induced by the mouse transformed macrophage J774, human monocyte-derived macrophages and vascular endothelial cells isolated from human umbilical cords. LDL modified by copper-catalysed or cell-induced oxidation was endocytosed and degraded by human macrophages at a much greater rate than native LDL. LDL reisolated from copper or cell incubations in the presence of (+)-catechin was endocytosed and degraded at rates similar to native LDL. (+)-Catechin appeared to inhibit the uptake and degradation by macrophages of cell-modified LDL. The actions of (+)-catechin on cell-induced oxidation of LDL are consistent with the ability of flavonoids of similar structure to inhibit lipoxygenases and with a role for lipoxygenases in cell-induced modification of LDL in vivo.  相似文献   
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