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991.
992.
Annual retrospective surveys of 20 to 31 medical centers performing endovascular treatment of cerebral aneurysms in Japan from 1997 to 2008 were performed to analyze technical and clinical outcomes of endovascular treatment for ruptured cerebral aneurysm. Patients treated with dome embolization using bare platinum coils within 14 days after onset were retrospectively selected, and clinical features, and technical and clinical outcomes at discharge were studied. Retrospective Endovascular Subarachnoid Aneurysm Treatment (RESAT) 1 covers patients treated from 1997, when the Guglielmi detachable coil was introduced, to 2002, just after International Subarachnoid Aneurysm Trial was reported. RESAT 2 to RESAT 7 were conducted annually between 2003 and 2008. Among 5,624 patients with ruptured aneurysms treated within 14 days after onset, 4,782 patients were treated by dome embolization using platinum detachable coils. The patients in this large retrospective survey included 35.8% aged over 70 years, 36.6% with posterior circulation aneurysms, and 29.3% with poor grades (Hunt and Kosnik grades IV and V). The proportion of patients aged over 70 years tended to increase each year from 33.4% in RESAT 1 to 39.8% in RESAT 7, and the proportion of those with posterior circulation aneurysms decreased from 44.2% in RESAT 1 to 23.8% in RESAT 7 (p<0.001). Overall technical success was obtained in 4,666 patients (97.6%), and favorable clinical outcome (good recovery and moderate disability) at discharge was obtained in 88.0% of grade I-III cases and 73.6% of grade I-V cases. Procedure-related morbidity was 2.9% and mortality was 0.8%. Despite this survey involving high proportions of aged, posterior circulation, and poor-grade patients, the technical success rate and immediate clinical results were relatively favorable. The patient prognosis and aneurysm changes must be investigated over a longer period, together with the effects of the introduction of new endovascular devices for cerebral aneurysms.  相似文献   
993.
A 39-year-old male presented with gait disturbances with rapid deterioration for 2 weeks. Neurological examination found paraparesis, sensory loss in the L1-S5 dermatomes, and vesicorectal dysfunction. Magnetic resonance (MR) imaging revealed a fusiform intramedullary tumor at T12-L1 levels with heterogeneous enhancement. The patient underwent microsurgical tumor resection. A myelotomy exposed a highly vascular tumor that was subtotally resected. Histological examination demonstrated hypercellular tumor accompanied by significant cell atypism and mitotic figures. Immunohistochemical staining was positive for glial fibrillary acidic protein, S-100 protein, synaptophysin, and INI-1, consistent with primitive neuroectodermal tumor (PNET). Postoperatively, the patient underwent irradiation to the whole craniospinal axis. He experienced local recurrence 7 months after surgery. MR imaging performed at 10 months revealed holocord progression and intracranial dissemination. The patient died 13 months after the onset of the disease. PNET should be considered in the differential diagnosis of an intramedullary spinal cord tumor.  相似文献   
994.
995.
A 73-year-old woman suffering from an abdominal aortic aneurysm (AAA), unstable angina, and low cardiac function (32% of ejection fraction) was scheduled for abdominal aortic replacement and coronary artery bypass grafting. However, before the scheduled operation the patient fell into cardiopulmonary arrest with ventricular fibrillation due to rupture of the AAA. Immediate cardiopulmonary resuscitation (CPR) using epinephrine and electrical defibrillation restored the spontaneous circulation. Following CPR, a continuous high-dose dopamine infusion (15 μg/kg/min) was initiated and emergent abdominal aortic replacement was performed. On arrival at the operating room, the patient showed serious hypotension, atrial fibrillation with multifocal ventricular premature contractions, and metabolic acidosis. Transesophageal echocardiography (TEE) suggested that the circulatory collapse might have resulted from diastolic dysfunction and deteriorated compliance of the left ventricular (LV) wall, possibly due to myocardial stunning induced by myocardial ischemia, and tachycardia induced by hypovolemia, both of which are influenced by high doses of catecholamine. We accordingly transfused adequate amounts of blood products and gradually decreased the infusion rate of dopamine to 4 μg/kg/min, while carefully monitoring blood pressure, central venous pressure, and TEE. By the end of surgery hemodynamic parameters had recovered to near normal levels. In post-resuscitated and hypovolemic patients, caution should be taken when administering high levels of exogenous catecholamines, which can induce myocardial stunning and circulatory collapse.  相似文献   
996.
Neural processes underlying identification of durational contrasts were studied by comparing English and Japanese speakers for Japanese short/long vowel identification relative to consonant identification. Enhanced activities for non-native contrast (Japanese short/long vowel identification by English speakers) were observed in brain regions involved with articulatory-auditory mapping (Broca's area, superior temporal gyrus, planum temporale, and cerebellum), but not in the supramarginal gyrus. Greater activity in the supramarginal gyrus found for the consonant identification over short/long vowel identification by Japanese speakers implies that it is more important for phonetic contrasts differing in place of articulation than for vowel duration. These results support the hypothesis that neural processes used to facilitate perception depend on the relative contribution of information important for articulatory planning control.  相似文献   
997.
998.
BACKGROUND: The pig pancreas is considered to be the most suitable source of islets for xenotransplantation in patients with type I diabetes. The objective of this study was to assess the antigenicity of neonatal porcine islet-like cell clusters (NPCC), including the Galalpha1-3Galbeta1-4GlcNAc-R (alpha-Gal) and Hanganutziu-Deicher (H-D) antigens, and the pathway involved in human complement activation. The efficiency of expression of human decay-accelerating factor (DAF: CD55) on NPCC by adenoviral transduction was also examined, and the functional capacity of DAF was also estimated. METHODS: The deposition of human natural antibodies, immunoglobulin (Ig)G and IgM, and the expression of alpha-Gal and H-D antigens on NPCC were investigated by FACS analysis. The downregulation in the antigenicity to human natural antibodies, including the alpha-Gal and H-D antigens on NPCC by treatment with tunicamycin, PDMP and neuraminidase were also examined. In addition, complement-mediated islet lysis was examined using factor D-deficient and C1-deficient sera. An adenovirus encoding DAF under the control of the cytomegalovirus promoter, Ad.pCMV-DAF, was then constructed, and used for transducing NPCC. The amelioration of complement-dependent cytotoxicity of the NPCC by the transduced DAF was assessed as an in vitro hyperacute rejection model of a pig to human xenograft. RESULTS: The NPCC clearly expressed the alpha-Gal epitope, and the human natural antibodies, IgG and IgM, and the anti-H-D antibody also reacted with the NPCC. Treatment of NPCC with tunicamycin led to a drastic reduction in the extent of deposition of IgG, indicating the importance of N-linked sugars on the islets, presumably related to alpha-Gal expression on N-linked sugars. Neuraminidase treatment indicated the presence of, not only the H-D antigen, but also other sialic acid antigens which reacted with the human natural antibody, especially IgG. The complement deposition of factor B on NPCC was clear, and the alternative pathway-mediated NPCC killing accounted for approximately 30% of that by the total complement pathway. On the other hand, approximately 90% of the NPCC could be transduced to express DAF by the adenovector, Ad.pCMV-DAF. The expressed DAF showed an approximately 50-62% suppression in complement-dependent NPCC lysis. CONCLUSION: The origin of the antigenicity of NPCC is mainly N-linked sugars including alpha-Gal and sialic acid antigens, and NPCC expressed the transduced molecule in high efficiency by the adenovector.  相似文献   
999.
Aortic root replacement after aortic valve replacement (AVR) is often complicated by bleeding around the aortic root, which increases the risk of morbidity and mortality, making it a technically challenging procedure. We describe a new technique of aortic root replacement designed to minimize bleeding around the aortic root. This surgical technique focuses on safe dissection and exposure of the aortic root to avoid inadvertent entry into the right atrium or right ventricle; on modifying the proximal anastomosis of the graft to the aortic annulus; and on performing a coronary artery reimplantation that achieves complete hemostasis at the suture lines. We performed aortic root replacement after AVR in four patients over a 4-year period, without encountering any bleeding around the aortic root.  相似文献   
1000.
We report a rare case of generalized peritonitis caused by nontraumatic, intraperitoneal rupture of the ureter. An 80-year-old woman with a history of bilateral vesicoureteral reflux and long-term urethral indwelling catheter drainage presented with a very distended abdomen. Computed tomography showed massive ascites and intraperitoneal free gas. We performed an emergency laparotomy, assuming a gastrointestinal perforation; but could not find a cause of generalized peritonitis. Postoperatively, she presented with anuria and massive peritoneal drainage. The findings of a cystogram confirmed intraperitoneal ureteral rupture. She was managed successfully with ureteral stenting. The diagnosis of this condition requires a high degree of clinical suspicion, along with radiographic evidence and peritoneal fluid analysis. Image-guided interventions play a crucial role in the management of ureteral urine leaks after a correct diagnosis has been made.  相似文献   
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