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991.
The aim of this article is to describe the current ultrasound (US) contrast agents employed in the characterization of renal tumors and to report our experience in the use of a contrast-specific ultrasound technique pulse inversion harmonic imaging (PIHI).A total of 23 renal masses were prospectively evaluated by conventional US, CDUS, PIHI and finally by helical-CT (HCT). The study was performed using a wideband convex array 2–5 MHz transducer and a US digital apparatus . PIHI scanning of each renal mass was performed before and after the injection of Levovist. To reach a definitive diagnosis HCT and/or histological findings were considered as the reference procedures. Eleven solid renal cell carcinomas (RCCs), one embryonal metanephric adenoma (EMA), seven angiomyolipomas (AMLs), and four cystic RCCs were analyzed. Solid RCCs revealed a higher contrast enhancement than AMLs with a typical pattern on conventional US. The EMA and AML with an atypical pattern revealed intense contrast enhancement during the arterial phase, progressively decreasing during the delayed phase. Cystic RCCs showed intense contrast enhancement on the peripheral thick wall during the arterial phase decreasing during the delayed phase. PIHI with Levovist may differentiate solid RCCs from AMLs with no hypervascular pattern while solid RCCs show a higher intensity of contrast enhancement than hypervascular AML.  相似文献   
992.
Selection and implementation of behavioral tests in spinal cord injury research is an important process, and yet few papers have focused on these issues. The critical component of any behavioral experiment is the ability to produce reliable, reproducible, and worthwhile data. Unfortunately, the difference between worthwhile and worthless data is often subtle. This paper describes factors that must be considered in order to select the most sensitive behavioral tests to match the hypothesis of the experiment and apply any test in a standardized, consistent manner. Classifications of behavioral tests, their strengths and limitations, as well as methods to overcome these limitations are discussed. Recent work in translating behavioral tests from rats to mice is also provided. The purpose of this article is to provide a framework by which behavioral testing can be standardized within and across spinal cord injury labs.  相似文献   
993.
Technical aspects in living-related liver transplantation are still under debate: the main pitfall is the arterial reconstruction due to the small diameter and the discrepancy between stumps, with a subsequent increased risk of arterial thrombosis. The gold standard is the microsurgical technique, that reports the lowest risk of thrombosis, but it is a time consuming procedure requiring a long training. Our method of choice reconstructing hepatic artery in right lobe is the use of the cystic artery as a branch patch with the recipient hepatic artery by loop magnification, saving time and with a low incidence of hepatic artery thrombosis.  相似文献   
994.
Background/Purpose We evaluated the role of operative cholangiography and of conversion to decrease major bile duct injuries.Methods We report 1074 patients who underwent laparoscopic cholecystectomy, out of a total of 1195 patients who underwent laparoscopy, over an 8-year period. The planned laparoscopic operative procedure in all the patients was the standard four-port technique with the operator on the left side of the patient. Operative cholangiography was performed with Olsens pliers.Results We performed 993 (83%) operative cholangiographies; 121 (10.1%) patients were converted from laparoscopic to open cholecystectomy. Despite a prolonged time of dissection, 54 (4.5%) patients were converted because of unclear anatomy of Calots triangle. One hundred and ninety patients suffered acute cholecystitis and, of those, 52 (27.3% of 190 patients) were converted. Fifteen patients showed intraoperative biliary duct stones and they were converted. Seven (0.58%) bile duct injuries (one stricture and six fistulas) are reported.Conclusions The low number of major bile duct injuries reported in our study showed the value of operative cholangiography during laparoscopic cholecystectomy. Moreover, another important factor found to reduce major bile duct injuries was conversion when, despite accurate dissection, the anatomy of Calots triangle remained unclear.Presented at the poster session of the 103rd Congress of The Japan Surgical Society, Sapporo, Hokkaido, Japan, June 2003, and published in abstract form in the Journal of the Japan Surgical Society (2003) 104: 1072–1073 (data-related years 1993–2000).  相似文献   
995.
OBJECTIVE: To investigate the influence of a calibrated exercise on the progression of structural lesions in an experimental model of osteoarthritis (OA) in the rat, and to explore the effect of exercise on the level of chondrocyte caspase-dependent apoptosis and of Hsp70. METHODS: The OA model was induced by anterior cruciate ligament transection (ACLT). Rats were placed in 4 experimental groups: operated (ACLT) free moving rats, and 3 exercise groups (slight, moderate and intense) subjected to running training. Rats were killed 14 and 28 days after surgery. RESULTS: On D14 histological assessment demonstrated a beneficial influence of a slight and a moderate exercise vs control ACLT group. Hsp70 increased significantly in the moderate group vs controls. On D28, histological lesions strongly decreased in the slight and moderate exercise groups vs ACLT group, while an intense effort abolished this beneficial trend. Interestingly, the concomitant course of apoptotic events (caspase 3-positive cells) and the co-expression of Hsp70 in the various groups varied, when significant, in an inverse manner. In the intense group this overexpression was not noted, as a "burn out" appeared, thus leading to a loss of this protective effect. CONCLUSION: This study shows that a calibrated slight or moderate exercise exerts a beneficial influence on the severity of chondral lesions in ACLT rats. Conversely, a strong effort abolishes this chondroprotective effect. This effect could be related to a reduced level of chondrocyte apoptosis through anti-apoptotic capacities of stress-induced Hsp70 overexpression.  相似文献   
996.
Members of the TGFbeta superfamily and EGF-CFC family, such as Nodal and Cripto, are important mediators of anterior-posterior and left-right axis specification during embryogenesis. In this paper, we review the role of Nodal and Cripto as critical morphogen-like molecules, with an emphasis on Nodal and EGF-CFC signaling during embryonic pattern formation. New evidence from gene expression and transgenic mouse studies have shown that both Nodal and Cripto-1 are expressed within the mammary duct and that modulation of these genes can disrupt normal branching morphogenesis resulting in epithelial disorganization and defective ductal architecture. We describe these new findings and propose that Cripto and Nodal are candidate mammary morphogens. Finally, the data linking overexpression of Cripto and perturbations of Cripto signaling to cell transformation and tumor formation are discussed. The fact that Cripto can modulate multiple pathways suggests it may act to deregulate growth inhibitors/homeostasis factors early in the cell transformation process and then activate prosurvival pathways dependent on MAPK and PI3K/Akt later in fully transformed phenotypes.  相似文献   
997.
998.
Legionella pneumonia is commonly diagnosed in patients who are chronically immunosuppressed, but it is rarely diagnosed in patients who have HIV/AIDS. We report the successful diagnosis and treatment of Legionella pneumonia in a patient with HIV infection that was diagnosed at the same admission.  相似文献   
999.
The Ensembl analysis pipeline   总被引:4,自引:0,他引:4       下载免费PDF全文
The Ensembl pipeline is an extension to the Ensembl system which allows automated annotation of genomic sequence. The software comprises two parts. First, there is a set of Perl modules ("Runnables" and "RunnableDBs") which are 'wrappers' for a variety of commonly used analysis tools. These retrieve sequence data from a relational database, run the analysis, and write the results back to the database. They inherit from a common interface, which simplifies the writing of new wrapper modules. On top of this sits a job submission system (the "RuleManager") which allows efficient and reliable submission of large numbers of jobs to a compute farm. Here we describe the fundamental software components of the pipeline, and we also highlight some features of the Sanger installation which were necessary to enable the pipeline to scale to whole-genome analysis.  相似文献   
1000.
BACKGROUND: Despite the sophisticated cross sectional image techniques currently available, a number of biliary stenosis or obstructions remain of an uncertain nature. In these pathological conditions, an "intrinsic" parietal alteration is the cause of biliary obstruction and it is very difficult to differentiate benign from malignant lesions using cross-sectional imaging procedures alone. We evaluated the efficacy of different endoluminal techniques to achieve a definitive pathological diagnosis in these situations. METHODS: Eighty patients underwent brushing, and or biopsy of the biliary tree through an existing transhepatic biliary drainage route. A subcoort of 12 patients needed balloon-dilatation of the bile duct and the material covering the balloon surface was also sent for pathological examination (balloon surface sampling). Pathological results were compared with surgical findings or with long-term clinical and instrumental follow-ups. Success rates, sensitivity, specificity, accuracy, confidential intervals, positive predictive value and negative predictive value of the three percutaneous techniques in differentiating benign from malignant disease were assessed.The agreement coefficient of biopsy and brushing with final diagnosis was calculated using the Cohen's "K" value. RESULTS: Fifty-six patients had malignant strictures confirmed by surgery, histology, and by clinical follow-ups. Success rates of brushing, balloon surface sampling, and biopsy were 90.7, 100, and 100%, respectively. The comparative efficacy of brushing, balloon-surface sampling, and biopsy resulted as follows: sensitivity of 47.8, 87.5, and 92.1%, respectively; specificity of 100% for all the techniques; accuracy of 69.2, 91.7 and 93.6%, Positive Predictive Value of 100% for all the procedures and Negative Predictive Value of 55, 80, and 75%, respectively. CONCLUSIONS: Percutaneous endoluminal biopsy is more accurate and sensitive than percutaneous bile duct brushing in the detection of malignant diseases (p < 0.01).  相似文献   
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