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991.
992.
Today, more men than ever before are being followed after radical prostatectomy. Prognosis and follow-up should be based on the pathologic specimen. Measurable prostate-specific antigen (PSA) after surgery defines failure, with time to detectable PSA and rate of PSA rise being useful prognostic factors. The natural history of untreated biochemical failure is protracted, a fact to be considered in discussions of adjuvant treatment. Early in disease recurrence, imaging studies to locate residual disease rarely are useful clinically. Both adjuvant and salvage radiation to the prostate bed have benefits and risks, but neither is superior in overall prostate cancer survival. The timing of hormone therapy remains largely empiric. The promise of effective cytotoxic chemotherapy still is greater than its actual benefits, although novel cytostatic agents are being developed. The future management of this disease will improve with better molecular definition of risk and therapeutic response.  相似文献   
993.
994.
Patients who present with a ruptured acute appendicitis are often treated with antibiotic therapy and drainage followed by a delayed or interval appendectomy. We noticed interval appendectomy specimens with granulomatous inflammation and postulated that interval appendectomy may lead to granulomatous appendicitis. To test this hypothesis, we reviewed the histopathology of all interval appendectomy specimens within a 4-year period and compared them with a control group of patients who had acute appendicitis and underwent routine acute appendectomy. All slides were randomized and reviewed blindly to assess the inflammatory patterns, with special attention given to the presence of granulomas and other Crohn-like features. Twenty-two cases of interval appendectomy were found. The interval between symptom onset and appendectomy ranged from 30 to 95 days with a mean of 58 days, whereas all 44 control patients had surgery within 72 hours of symptoms onset. Thirteen (59.1%) of the 22 interval appendectomy cases contained granulomas compared with only 3 of 44 controls (P < 0.0001). Eight (36.4%) of the interval appendectomy cases had xanthogranulomatous inflammation compared with none in the acute appendicitis group (P < 0.0001). A Crohn-like appearance was seen in 11 (50.0%) of the interval appendectomy cases and 1 of the controls (P < 0.0001). Follow-up data were available in 8 of 11 cases with Crohn-like features; none developed Crohn disease during an average follow-up period of 23 months. Delayed or interval appendectomy specimens often have a characteristic inflammatory pattern that includes granulomas, xanthogranulomatous inflammation, mural fibrosis/thickening, and transmural chronic inflammation. Without the appropriate clinical history, these changes may be misinterpreted as Crohn disease.  相似文献   
995.
Previously, we detected pathogenic (invasive) DNA in the appendices of two patients who later developed Crohn's disease (CD). This subsequent investigation is the first to evaluate a series of specimens from CD patients for the presence of pathogenic DNA. A total of 54 intestinal resection specimens from 52 patients with confirmed CD were evaluated. Lesional tissue was tested by polymerase chain reaction analysis for the presence of genes occurring only in pathogenic Primer pairs are specific for each species, with no known cross reactions with other bacteria. Forty normal bowel specimens, 30 cases of acute appendicitis, and 50 cases of various active colitides served as disease controls. Medical records were reviewed following polymerase chain reaction and histologic evaluation. A total of 17 of 54 resections (31%) contained DNA by polymerase chain reaction. Mesenteric lymph nodes were also positive in eight of these cases. All controls were negative. -positive patients had carried the diagnosis of CD for a median of 10 years before resection (range 1 month to 40 years). We report the first documentation of DNA in a series of CD cases. Further studies are needed, including serial study, over time, of -positive CD patients, as well as prospective studies of newly diagnosed CD patients for evidence of infection. Like previous studies associating infectious organisms with CD, much work remains to elucidate whether the presence of DNA is an epiphenomenon or actually a factor in the pathogenesis of CD.  相似文献   
996.
Extensive experience with dural sinus thrombosis   总被引:7,自引:0,他引:7  
Soleau SW  Schmidt R  Stevens S  Osborn A  MacDonald JD 《Neurosurgery》2003,52(3):534-44; discussion 542-4
OBJECTIVE: Dural sinus thrombosis (DST) is an uncommon cause of stroke. The safest and most effective therapy for DST has not been conclusively identified. METHODS: A retrospective chart review of data for 31 patients who were treated for DST at our institution between 1992 and 2001 was performed. Four treatment strategies were identified, i.e., 1). medical observation only, 2). systemic anticoagulation (AC) therapy with heparin, 3). endovascular chemical thrombolysis with urokinase or tissue plasminogen activator and concurrent systemic AC therapy, and 4). mechanical endovascular clot thrombolysis with concurrent systemic AC therapy. Complications and clinical outcomes were assessed for each group. RESULTS: Patients treated solely with medical observation fared the worst; four of five patients experienced intracranial hemorrhagic complications, and only two of five exhibited clinical improvement. Patients who received systemic AC therapy experienced no hemorrhagic complications, even when pretreatment hemorrhage was present; 75% (six of eight patients) exhibited improvement with AC therapy alone. Chemical thrombolysis was very effective in restoring sinus patency (90% of patients); however, 30% of patients (3 of 10 patients) experienced hemorrhagic complications. Sixty percent of patients (6 of 10 patients) who underwent chemical thrombolysis exhibited clinical improvement. Patients who underwent mechanical thrombectomies demonstrated a low hemorrhagic complication rate, and most (88%) made good recoveries. CONCLUSION: Therapy directed at the underlying clot in DST must begin without delay. Our results suggest that supportive medical management of DST, without therapy directed at the clot or clotting process, is not effective. Systemic AC therapy, even in the presence of intracerebral hemorrhage, seems to be safe. Heparin can be safely titrated to yield partial thromboplastin times of 60 to 70 seconds. Chemical clot thrombolysis is efficacious in opening occluded sinuses but may cause intracranial hemorrhage. We currently recommend either systemic AC therapy or systemic AC therapy in conjunction with mechanical clot thrombectomy as a safe effective treatment for DST.  相似文献   
997.
A bellows-based breath-hold monitoring and feedback system was developed and evaluated for use in intermittent-mode computed tomographic (CT) fluoroscopy-guided biopsy procedures in the lung or upper abdomen. The bellows system is described, and its feasibility is demonstrated in studies with a respiratory phantom and human volunteers. Results are reported for seven patients who underwent bellows-assisted biopsy. Breath-hold monitoring and feedback with the bellows system allow the patient to perform reliable breath holding at a preselected level. This optimizes intermittent-mode CT fluoroscopy-guided biopsies by allowing consistent visualization of the target lesion throughout the procedure.  相似文献   
998.
999.
OBJECTIVE: Our purpose is to describe the appearance of an argon beam coagulator electrode tip that may become fractured and detached during surgery. CONCLUSION: Knowledge of the potential for fracture and detachment and recognition of the characteristic radiographic appearance of the argon beam coagulator electrode tip allows radiographic identification of this metallic foreign body.  相似文献   
1000.
Adenosine in myocardial protection in on-pump and off-pump cardiac surgery   总被引:4,自引:0,他引:4  
Adenosine is most well known for its potent vasodilation of the vasculature. However, it also promotes glycolysis, and activates potassium-sensitive adenosine triphosphate (K(ATP)) channels. Adenosine also strongly inhibits neutrophil function such as superoxide anion production, protease release, and adherence to coronary endothelial cells. Hence adenosine attenuates ischemic injury as well as neutrophil-mediated reperfusion injury. Adenosine has also been implicated in the cardioprotective phenomenon of ischemic preconditioning. Accordingly experimental evidence shows that adenosine reduces postischemic injury when administered before ischemia and at the onset of reperfusion. Clinical studies in cardiology and cardiac surgery show cardioprotective trends with adenosine treatment but the effects are not as dramatic as those reported by experimental studies.  相似文献   
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