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61.
An Echinococcus granulosus genomic library has been screened with a mouse β-actin cDNA probe. Two clones carrying DNA fragments of about 15 kb, possibly derived from the same genome region, have been isolated. This 15-kb genomic region includes 2 actin-related sequences (EgactI and EgactII) separated by about 4 kb. The nucleotide sequences of both genes were determined. The EgactI sequence presents no introns, but an intron of 591 bp was observed in the EgactII sequence. The genes potentially encode 375 and 376 amino-acid-long actins, respectively, with a homology of 85.3%. The deduced amino acid sequences from both genes were compared to the actin sequences from other organisms, showing similarities ranging from 63.5% to 90.6%. The nucleotide sequence of a partial actin cDNA clone has been determined. The deduced amino acids sequence showed a homology of 90.3% and 88.0% in relation to the EgactI and EgactII sequences respectively, suggesting the existence of at least one more actin gene in E. granulosus. This hypothesis is reinforced by the number of bands detected in the Southern blot analysis. Experiments based on the amplification of DNA segments using 3′-specific actin primers indicate that the EgactI gene is transcribed in protoscoleces.  相似文献   
62.
AIM: The safety and effectiveness of transcatheter stent-graft treatment in the early and medium-term postoperative period was assessed in patients with DeBakey type III aortic dissection. METHODS: Transcatheter stent-graft implantation was performed in 37 patients who had aortic dissection with entry sites in the descending thoracic aorta. Entry sites were closed with a stent-graft consisting of a Gianturco Z stent covered with an UBE woven Dacron graft. RESULTS: There were no in-hospital deaths or serious complications after operation. In 5 patients, a new intimal tear developed at the distal end of the stent-graft 8 to 13 months after operation. It was closed by additional stent-graft placement in 2 patients. The rate of thrombosis of the false lumen of the descending thoracic aorta 5 to 10 days, 3 to 6 months, and 12 months after operation was 70%, 80%, and 81%, respectively. As compared with before operation, the short axis of the true lumen increased (1.4+/-0.8 cm before operation, 2.1+/-0.5 cm at 5-10 days, and 2.7+/-0.6 cm at 3-6 months) and that of the false lumen decreased (2.9+/-0.9 cm, 2.3+/-0.9 cm, 1.5+/-1.2 cm), indicating enlargement of the true lumen and shrinkage of the false lumen. The false lumen was completely obliterated within 3-6 months after operation in 6 patients. CONCLUSIONS: Our early postoperative results show that transcatheter stent-graft implantation is a safe and effective procedure for the management of DeBakey Type III aortic dissection. Devices with a minimal risk of causing intimal tears should be developed.  相似文献   
63.
Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease. Although several cases of BP in end-stage renal disease patients receiving peritoneal dialysis (PD) or hemodialysis have been reported, the incidence of BP in these patients remains unknown. We recently experienced three PD patients diagnosed with BP. The skin injury was likely to be a trigger of BP in all the three PD patients. Nifedipine and icodextrin exposures were possible factors directly or indirectly affecting the onset of BP, because they were common in the three cases. We also report that the incidence of BP in PD patients was 3/478.3 person-years in a single-center 10-year study. This case series with a literature survey describes that the skin and tissue injuries are potential triggers responsible for the onset of BP in dialysis patients and that the incidence of BP in these patients seems to be much higher than that in the general population.  相似文献   
64.
Upper gastrointestinal endoscopy of a 25‐year‐old man with heartburn revealed an elevated lesion in the esophagogastric junction (EGJ). Piecemeal endoscopic mucosal resection (EMR) followed by histopathological examination led to a diagnosis of inflammatory fibroid polyp (IFP). After EMR, the heartburn persisted despite giving a proton pump inhibitor (PPI), and the residual lesion gradually enlarged and a transverse mucosal break developed on the esophageal side of it. However, the combined administration of the PPI and an H2 receptor antagonist reduced the heartburn, and led to endoscopic regression of the lesion and disappearance of the transverse mucosal break. IFP of the esophagogastric junction is extremely rare, and this case is interesting in that potent inhibition of gastric acid secretion resulted in the regression of the lesion.  相似文献   
65.
The Cleveland Clinic CorAide left ventricular assist system is based on a third-generation, implantable, centrifugal pump in which a rotating assembly is suspended fully. To evaluate chronic in vivo system performance and biocompatibility, the CorAide blood pump was implanted in 18 calves for either 1 month or 3 months. Hemodynamics were stable in all calves with a mean pump flow of 5.9 +/- 1.2 L/min and a mean systemic arterial pressure of 98 +/- 5 mm Hg. There were no incidences of bleeding, organ dysfunction, or mechanical failure in any of the 18 calves. Hemolysis occurred in only 1 calf due to outflow graft stenosis. Thrombus inside the pump, seen in 4 of the first 6 cases, was totally eliminated by a final redesign in the remaining cases, including the last 6 implants conducted without anticoagulation therapy. The CorAide blood pump demonstrated good biocompatibility and reliable, effective system performance.  相似文献   
66.
We describe a 68-year-old man who underwent hyperbaric oxygen (HBO) therapy to manage radiation necrosis of the brain, which developed after two treatments with stereotactic radiosurgery (SRS) to the same lesion. The necrosis was subsequently treated with steroids alone for 2 months; however, he progressed clinically and radiographically. Improvement again was noted with the reinstitution of HBO therapy. This case suggests that HBO therapy is an important therapeutic option in the treatment of brain radiation necrosis caused by SRS.  相似文献   
67.
Arterial Mg2+ concentrations were analyzed in 108 patients with cerebral aneurysms. There was no difference in Mg2+ concentrations between patients with ruptured and unruptured aneurysms. Mg2+ concentrations in patients with ST depression or elevation were lower than in those without ST changes (0.34 +/- 0.05 vs. 0.38 +/- 0.07 mmol.l-1). Decreased arterial Mg2+ could be caused by cardiac ischemia rather than subarachnoid hemorrhage. For prevention of fatal arrhythmias, perioperative brain protection and ameliorating vasospasm, correcting the depressed Mg2+ concentrations is suggested.  相似文献   
68.
Toxicity of dichloropropanols   总被引:1,自引:0,他引:1  
A rare outbreak of acute hepatic damage in workers exposed to dichloropropanols was reported in 1992. As there are no detailed reports of dichloropropanols (DCPs) toxicity and its mechanism, we reviewed the toxicity of dichloropropanols using our results. 1) A marked elevation of serum AST and ALT with massive necrosis of the liver was noted in the 1/2 x, the 1 x and 2 x LD50 (0.149 mg/kg) of 1, 3-dichloro-2-propanol(DC 2 P). Hepatic malondialdehyde level was significantly increased, and associated with a decrease in liver glutathione S-transferase activity and reduced glutathione content. It is suggested that the free radical is associated with DCPs. 2) A reduction of leukocytes, platelets and fibrinogen, and prolonged prothrombin time were observed in the 1 x LD50 of DC 2 P. 3) In the CA1 area of the hippocampus, inhibition of population spikes was reduced by the 1 x LD50 of DC 2 P. This research was completed with the assistance of several other papers concerning dichloropropanols toxicity.  相似文献   
69.
OBJECTIVE: In order to investigate kainic acid (KA)-induced amygdaloid seizure and seizure-induced brain damage in dogs, and to compare these findings with that in other species, a KA-induced seizure model in dogs was produced. MATERIAL AND METHODS: Normal beagle dogs were used. A Teflon cannula for KA injection was inserted into the left amygdala, and cortical or depth electrodes were positioned. One week after surgery, 1.5 microg of KA was microinjected into the left amygdala. EEGs and the behavior of the animals were monitored for 2 months after KA injection. In addition, neuron-specific enolase levels in the cerebrospinal fluid (CSF-NSE) were measured intermittently. At 2 months after the injection, histopathological studies were performed. RESULTS: KA-treated dogs showed limbic seizures that started from the left amygdala within 30 min after injection. The seizures developed into complex partial status epilepticus (CPSE), and started independently from the bilateral amygdala during the CPSE. The CPSE lasted for 1-3 days, and the animals showed no spontaneous seizures during the 2-month observation period. A significant increase in CSF-NSE was observed immediately after CPSE. Histopathologically, extensive necrosis, which formed large cavity lesions, was observed around the bilateral amygdala. SUMMARY: A microinjection of KA into unilateral amygdala in dogs induced CPSE. The seizures elicited independently from bilateral amygdala, and bilateral limbic structures suffered extensive injury. In addition, CSF-NSE was demonstrated as a useful marker of acute neuronal damage.  相似文献   
70.
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