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Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
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We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength.  相似文献   
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PURPOSE: To report five patients with intraocular invasion of conjunctival squamous cell carcinoma and to make recommendations regarding clinical recognition and treatment of this condition. METHODS: The authors reviewed the clinical records and pathology slides on five patients who had intraocular invasion of conjunctival squamous cell carcinoma, and they describe the presenting features and histopathology in these cases. RESULTS: Intraocular invasion of conjunctival squamous cell carcinoma occurred in older patients who had one or more recurrences of a previously excised conjunctival epithelial tumor located near the comeoscleral limbus. The intraocular recurrence often was heralded by the onset of low-grade inflammation and secondary glaucoma, simulating a granulomatous iridocyclitis. A white mass generally was observed in the anterior chamber angle. Histopathologic examination revealed an ingrowth of malignant epithelial cells through the limbus with diffuse involvement of the anterior segment of the eye. The reported patients were managed by modified enucleation (standard enucleation with excision of affected conjunctival tissue). Metastatic disease did not develop in any of the patients. CONCLUSIONS: The onset of signs of uveitis and glaucoma and a white mass in the anterior chamber angle in a patient with prior excision of a conjunctival squamous cell neoplasm tumor should raise suspicion of intraocular recurrence of conjunctival squamous cell carcinoma. Most affected patients require enucleation or subtotal orbital exenteration. The prognosis is good.  相似文献   
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Giant cell reparative granuloma of the orbit   总被引:1,自引:0,他引:1  
PURPOSE: To report a case of giant cell reparative granuloma occurring in the orbit and to discuss its clinical, radiologic, and histopathologic characteristics in contrast with other similar lesions. METHODS: A 38-year-old man developed pain and mild proptosis of the left eye. Computed tomography and magnetic resonance imaging demonstrated an intraosseous cystic orbital mass. Excisional biopsy disclosed giant cell reparative granuloma of the orbit. RESULT: At 11 months' follow-up, the patient had normal vision, with no tumor recurrence. CONCLUSION: Giant cell reparative granuloma of the orbit is a rare benign fibro-osseous proliferation that is generally seen in young adulthood. It should be considered in the differential diagnosis of orbital fibro-osseous proliferation. Surgical excision and curettage is the therapeutic method of choice.  相似文献   
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Purpose : Peripheral stem cell transplantation is used as a life‐saving therapeutic option in hematological malignancies. As previously established, most hematological malignancies are seen in the elderly population. Therefore, possible HLA‐identical sibling donors of elderly patients are generally of an advanced age. In this study, we aimed to evaluate the effect of old age on stem cell mobilization and quality in older adult healthy sibling donors. Materials and Methods : Between 2006 and 2014, we evaluated 38 healthy donors aged ≥55 years. The granulocyte‐colony stimulating factor (G‐CSF) analogs were used at a dose of 5 µg/kg/day and administered subcutaneously twice a day for five days. CD34+ cells were estimated in the peripheral blood before collection of the apheresis product. The National Marrow Donor Program selects healthy unrelated donors if they are younger than 60 years. Therefore, we compared the product quality in donors over the age of 60 to that in donors aged 60 years or less. Results : We collected sufficient products from all the donors with one to three apheresis procedures. No serious complication was detected in all donors. Reaching the target CD34+ cell count in one day were detected in 83% of younger and 79% of older donors (P = NS). Collected CD34+ cells x10e6/recipient body weight (kg) was same and 5.1 in the groups (P = NS). There were no correlation between the donor age and these parameters. Conclusion : Healthy donor apheresis in older adults can be performed effectively and possible donors should be evaluated regardless of their age. J. Clin. Apheresis 32:16–20, 2017. © 2016 Wiley Periodicals, Inc.  相似文献   
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A 36‐year‐old female was admitted to hospital exhibiting chest pain, dyspnea, and a heart murmur on the right upper sternal border, radiating to both carotid arteries. The blood pressure of the patient's right arm exceeded the pressure in the left by 25 mm Hg (Coanda effect). In spite of laboratory results that did not fall outside the expected range, the left ventricle was revealed to be hypertrophic following electrocardiography. Transthoracic echocardiography revealed a severe supravalvular aortic stenosis (SVAS) with a peak Doppler velocity of 6.04 cm/s and an estimated mean pressure gradient of 89 mm Hg, with moderate aortic and mitral regurgitation. Contrast‐enhanced computed tomography (CCT) indicated a partial hourglass‐shaped narrowing of the ascending aorta. Lesions associated with supravalvular stenosis of the pulmonary artery, patent ductus arteriosus, and aortic coarctation were ruled out by the CCT. Congenital SVAS is a rare heart condition, and three anatomically distinct forms have been described. The most common type is the “hourglass,” which produces a marked thickening and disorganization of the aortic tissue, producing a constricting annular ridge at the superior margin of the sinuses of Valsalva.  相似文献   
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