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101.
102.
Phenotypic characterization of human colorectal cancer stem cells 总被引:35,自引:3,他引:35
Dalerba P Dylla SJ Park IK Liu R Wang X Cho RW Hoey T Gurney A Huang EH Simeone DM Shelton AA Parmiani G Castelli C Clarke MF 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(24):10158-10163
Recent observations indicate that, in several types of human cancer, only a phenotypic subset of cancer cells within each tumor is capable of initiating tumor growth. This functional subset of cancer cells is operationally defined as the "cancer stem cell" (CSC) subset. Here we developed a CSC model for the study of human colorectal cancer (CRC). Solid CRC tissues, either primary tissues collected from surgical specimens or xenografts established in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice, were disaggregated into single-cell suspensions and analyzed by flow cytometry. Surface markers that displayed intratumor heterogeneous expression among epithelial cancer cells were selected for cell sorting and tumorigenicity experiments. Individual phenotypic cancer cell subsets were purified, and their tumor-initiating properties were investigated by injection in NOD/SCID mice. Our observations indicate that, in six of six human CRC tested, the ability to engraft in vivo in immunodeficient mice was restricted to a minority subpopulation of epithelial cell adhesion molecule (EpCAM)(high)/CD44+ epithelial cells. Tumors originated from EpCAM(high)/CD44+ cells maintained a differentiated phenotype and reproduced the full morphologic and phenotypic heterogeneity of their parental lesions. Analysis of the surface molecule repertoire of EpCAM(high)/CD44+ cells led to the identification of CD166 as an additional differentially expressed marker, useful for CSC isolation in three of three CRC tested. These results validate the stem cell working model in human CRC and provide a highly robust surface marker profile for CRC stem cell isolation. 相似文献
103.
Priyadarshini Arunakumar DM Anoop Ayyappan MD Deepa Sasikumar DM KM Krishnamoorthy DM 《Echocardiography (Mount Kisco, N.Y.)》2018,35(5):733-734
A 12‐year‐old child presented with recurrent respiratory infections and was diagnosed with Scimitar syndrome. Drainage of IVC and course of aberrant arterial supply from aorta were not clear by echocardiogram, and hence, additional imaging was planned. CT unraveled the presence of a rare combination of anomalous pulmonary venous connection (APVC) to IVC, with near‐atresia/severe stenosis of IVC, superior to the drainage of scimitar vein. There was a prominent azygos vein with preferential contrast opacification on lower limb injection. 相似文献
104.
Nagaraja Moorthy DM Rajiv Ananthakrishna DM Dattatreya P. V. Rao DM Satvic C. Manjunath DM Manjunath C. Nanjappa DM 《Echocardiography (Mount Kisco, N.Y.)》2018,35(3):388-390
Intermittent dysfunction of mechanical mitral valve prosthesis is an uncommon condition. It carries serious clinical implications if unrecognized. Here, we present a case of a 28‐year‐old female with a history of rheumatic multivalvular disease, for which she had undergone double valve replacement and tricuspid annuloplasty. Six months later, she presented with heart failure. Clinical examination revealed intermittent loss of closing clicks followed by a pansystolic murmur at the apex, suggestive of mitral prosthetic valve dysfunction. We highlight the echocardiographic findings of paroxysmal mitral valvular regurgitation secondary to prosthetic valve malfunction secondary to prosthetic valve thrombosis. 相似文献
105.
106.
Krishna Prasad Gourav MD DM Subhrashis Guha Niyogi MD Vikram Halder MS Sunder Negi MD DM Avneet Singh MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(7):1114-1115
Patients with large sub-pulmonic ventricular septal defect (VSD) present early as a results of their complications. Some present late, due to the restriction of VSD by the right coronary cusp (RCC) due to its prolapse. In this report, we present a rare case of sub-pulmonic VSD in a 33-year-old man who developed a sub-pulmonic stenosis due to the prolapse of the RCC into the right ventricular outflow tract. 相似文献
107.
Oleksandr Danylenko MD PhD Elena Surkova MD PhD Roxy Senior MD DM Wei Li MD PhD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(8):1315-1317
Accurate assessment of etiology of mitral regurgitation (MR) is one of the key steps in the decision-making process and further clinical management of patients with severe MR. Our clinical case illustrates the added value of three-dimensional echocardiography (3DE) in assessment of mitral valve morphology and identification of an unexpected mechanism of MR which was not previously diagnosed using conventional echocardiography. 3DE helped to choose appropriate management strategy in this patient. 相似文献
108.
Deepa Sasikumar DM Anoop Ayyappan DM Jineesh Valakkada DM Kavasseri Mahadevan Krishnamoorthy DM 《Echocardiography (Mount Kisco, N.Y.)》2020,37(9):1492-1494
Saline contrast echocardiography is a simple and effective method to diagnose the presence and type of right-to-left shunt in patients with unexplained cyanosis. It is considered a very sensitive test to diagnose pulmonary arteriovenous malformations. Our patient presented with unexplained cyanosis and transthoracic echocardiography showed an atrial septal defect and anomalous pulmonary venous drainage of the right and left upper pulmonary veins to the superior venacava. We describe how we used saline contrast echocardiography to demonstrate the presence of pulmonary arteriovenous malformations even in the presence of atrial septal defect and anomalous pulmonary venous drainage. 相似文献
109.
Jay Relan MD DM Mrigank Choubey MD Shyam Sunder Kothari MD DM 《Echocardiography (Mount Kisco, N.Y.)》2020,37(12):2168-2170
In cor triatriatum sinister, the left atrium is divided by a membrane into a proximal and a distal chamber. Usually proximal chamber receives all the pulmonary veins and drains through an opening in the dividing membrane into distal chamber, which empties into left ventricle through the mitral valve. Rarely, the two chambers lack a communication and there is associated total anomalous pulmonary venous connection (TAPVC). We report a 1-month-old infant with cyanosis and heart failure, who had cor triatriatum sinister associated with supracardiac TAPVC. The case is reported for rarity of the association with a focus on contrast echocardiographic imaging. 相似文献