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排序方式: 共有2090条查询结果,搜索用时 15 毫秒
981.
Catherine Madorin Randall P. Owen William D. Fraser Phillip K. Pellitteri Brian Radbill Alessandra Rinaldo Raja R. Seethala Ashok R. Shaha Carl E. Silver Matthew Y. Suh Barrie Weinstein Alfio Ferlito 《European archives of oto-rhino-laryngology》2012,269(6):1565-1576
Secondary and tertiary hyperparathyroidism (HPT) develop in patients with renal failure due to a variety of mechanisms including increased phosphorus and fibroblast growth factor 23 (FGF23), and decreased calcium and 1,25-dihydroxy vitamin D levels. Patients present with various bone disorders, cardiovascular disease, and typical laboratory abnormalities. Medical treatment consists of controlling hyperphosphatemia, vitamin D/analog and calcium administration, and calcimimetic agents. Improved medical therapies have led to a decrease in the use of parathyroidectomy (PTX). The surgical indications include parathyroid hormone (PTH) levels >800?pg/ml associated with hypercalcemia and/or hyperphosphatemia despite medical therapy. Other indications include calciphylaxis, fractures, bone pain or pruritis. Transplant recipients often show decreased PTH, calcium and phosphorus levels, but some will have persistent HPT. Evidence suggests that PTX may cause deterioration in renal graft function in the short-term calling into the question the indications for PTX in these patients. Pre-operative imaging is only occasionally helpful except in re-operative PTX. Operative approaches include subtotal PTX, total PTX with or without autotransplantation, and possible thymectomy. Each approach has its proponents, advantages and disadvantages which are discussed. Intraoperative PTH monitoring has a high positive predictive value of cure but a poor negative predictive value and therefore is of limited utility. Hypocalcemia is the most common complication requiring aggressive calcium administration. Benefits of surgery may include improved survival, bone mineral density and alleviation of symptoms. 相似文献
982.
Gupte SA Levine RJ Gupte RS Young ME Lionetti V Labinskyy V Floyd BC Ojaimi C Bellomo M Wolin MS Recchia FA 《Journal of molecular and cellular cardiology》2006,41(2):340-349
In the failing heart, NADPH oxidase and uncoupled NO synthase utilize cytosolic NADPH to form superoxide. NADPH is supplied principally by the pentose phosphate pathway, whose rate-limiting enzyme is glucose 6-phosphate dehydrogenase (G6PD). Therefore, we hypothesized that cardiac G6PD activation drives part of the excessive superoxide production implicated in the pathogenesis of heart failure. Pacing-induced heart failure was performed in eight chronically instrumented dogs. Seven normal dogs served as control. End-stage failure occurred after 28 +/- 1 days of pacing, when left ventricular end-diastolic pressure reached 25 mm Hg. In left ventricular tissue homogenates, spontaneous superoxide generation measured by lucigenin (5 microM) chemiluminescence was markedly increased in heart failure (1338 +/- 419 vs. 419 +/- 102 AU/mg protein, P < 0.05), as were NADPH levels (15.4 +/- 1.5 vs. 7.5 +/- 1.5 micromol/gww, P < 0.05). Superoxide production was further stimulated by the addition of NADPH. The NADPH oxidase inhibitor gp91(ds-tat) (50 microM) and the NO synthase inhibitor L-NAME (1 mM) both significantly lowered superoxide generation in failing heart homogenates by 80% and 76%, respectively. G6PD was upregulated and its activity higher in heart failure compared to control (0.61 +/- 0.10 vs. 0.24 +/- 0.03 nmol/min/mg protein, P < 0.05), while superoxide production decreased to normal levels in the presence of the G6PD inhibitor 6-aminonicotinamide. We conclude that the activation of myocardial G6PD is a novel mechanism that enhances NADPH availability and fuels superoxide-generating enzymes in heart failure. 相似文献
983.
Hamoir M Ferlito A Schmitz S Hanin FX Thariat J Weynand B Machiels JP Grégoire V Robbins KT Silver CE Strojan P Rinaldo A Corry J Takes RP 《Oral oncology》2012,48(3):203-210
Concurrent chemotherapy and radiotherapy (CRT) has become standard treatment for many patients with advanced head and neck squamous cell carcinoma (HNSCC). This has led to controversy concerning the role of neck dissection (ND) in this setting. The current debate is focused on N2-N3 disease and the ability of a clinical complete response to predict the absence of viable cells in the ND specimen. Proponents of a systematic planned ND argue that it improves regional control and possibly disease-specific survival. They assert that a clinical response does not predict the pathologic response, and that in the event of recurrence in the neck, a surgical salvage procedure is unlikely to succeed. Conversely, there are many arguments in favor of performing ND only for patients who have evidence of residual neck disease because of the very low probability of isolated neck recurrence following a complete response. Proponents argue that for complete responders, planned ND is associated with no survival benefit. As planned surgery will only benefit patients with residual disease in the neck alone, there is a high rate of unnecessary ND with its associated morbidity. Another question concerns the appropriate type of ND to be performed. Even if required after chemoradiation, selective ND is oncologically feasible with minimal morbidity. Lastly, robust data from a randomized trial demonstrating the superiority of one approach vs. the other are lacking. After conducting a review of recent literature on the subject, the authors conclude that planned ND is not necessary for patients with complete response because of the availability of improved diagnostic follow up modalities, and the increased sensitivity to CRT of HNSCC, particularly HPV associated tumors. 相似文献
984.
985.
Carlos Estrela Mike Reis Bueno Ana Helena Gonçalves De Alencar Rinaldo Mattar José Valladares Neto Bruno Correa Azevedo Cyntia Rodrigues De Araújo Estrela 《Journal of endodontics》2009,35(11):1491-1497
IntroductionThe aim of this study was to evaluate a method to measure inflammatory root resorption (IRR) by using cone beam computed tomography (CBCT) scans.MethodsIRR sites were classified according to root third and root surface, and IRR extension was measured on the axial, transverse, and tangent views of 3-dimensional CBCT scans by using the Planimp software. A 5-point (0–4) scoring system was used to measure the largest extension of root resorption. A total of 48 periapical radiographs and CBCT scans originally taken from 40 patients were evaluated. The kappa coefficient was used to assess interobserver agreement and the χ2 test to determine significant differences between the imaging methods. The level of significance was set at α = 1%.ResultsIRR was detected in 68.8% (83 root surfaces) of the radiographs and 100% (154 root surfaces) of the CBCT scans (P < .001). The extension of IRR was >1–4 mm in 95.8% of the CBCT images and in 52.1% of the images obtained by using the conventional method (P < .001).ConclusionsCBCT seems to be useful in the evaluation of IRR, and its diagnostic performance was better than that of periapical radiography. 相似文献
986.
GAS6 Inhibits Granulocyte Adhesion to Endothelial Cells 总被引:4,自引:1,他引:3
Avanzi Gian Carlo; Gallicchio Margherita; Bottarel Flavia; Gammaitoni Loretta; Cavalloni Giuliana; Buonfiglio Donatella; Bragardo Manuela; Bellomo Giorgio; Albano Emanuele; Fantozzi Roberto; Garbarino Giovanni; Varnum Brian; Aglietta Massimo; Saglio Giuseppe; Dianzani Umberto; Dianzani Chiara 《Blood》1998,91(7):2334-2340
987.
988.
989.
A fetal fatty-acid oxidation disorder as a cause of liver disease in pregnant women. 总被引:25,自引:0,他引:25
J A Ibdah M J Bennett P Rinaldo Y Zhao B Gibson H F Sims A W Strauss 《The New England journal of medicine》1999,340(22):1723-1731
BACKGROUND: Acute fatty liver of pregnancy and the HELLP syndrome (hemolysis, elevated liver-enzyme levels, and a low platelet count) are serious hepatic disorders that may occur during pregnancy in women whose fetuses are later found to have a deficiency of long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase. This enzyme resides in the mitochondrial trifunctional protein, which also contains the active site of long-chain 2,3-enoyl-CoA hydratase and long-chain 3-ketoacyl-CoA thiolase. We undertook this study to determine the relation between mutations in the trifunctional protein in infants with defects in fatty-acid oxidation and acute liver disease during pregnancy in their mothers. METHODS: In 24 children with 3-hydroxyacyl-CoA dehydrogenase deficiency, we used DNA amplification and nucleotide-sequence analyses to identify mutations in the alpha subunit of the trifunctional protein. We then correlated the results with the presence of liver disease during pregnancy in the mothers. RESULTS: Nineteen children had a deficiency only of long-chain 3-hydroxyacyl-CoA dehydrogenase and presented with hypoketotic hypoglycemia and fatty liver. In eight children, we identified a homozygous mutation in which glutamic acid at residue 474 was changed to glutamine. Eleven other children were compound heterozygotes, with this mutation in one allele of the alpha-subunit gene and a different mutation in the other allele. While carrying fetuses with the Glu474Gln mutation, 79 percent of the heterozygous mothers had fatty liver of pregnancy or the HELLP syndrome. Five other children, who presented with neonatal dilated cardiomyopathy or progressive neuromyopathy, had complete deficiency of the trifunctional protein (loss of activity of all three enzymes). None had the Glu474Gln mutation, and none of their mothers had liver disease during pregnancy. CONCLUSIONS: Women with acute liver disease during pregnancy may have a Glu474Gln mutation in long-chain hydroxyacyl-CoA dehydrogenase. Their infants are at risk for hypoketotic hypoglycemia and fatty liver. 相似文献