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1.
Madan M. Rehani Emily R. Melick Raza M. Alvi Ruhani Doda Khera Salma Batool-Anwar Tomas G. Neilan Michael Bettmann 《European radiology》2020,30(4):1839-1846
To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria. 相似文献
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Sergue? O Fetissov Jarmila Hallman Ida Nilsson Ann-Kari Lefvert Lars Oreland Tomas H?kfelt 《Neuropsychopharmacology》2006,60(8):799-802
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones. 相似文献
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We would like to thank Professor Erdem Kasikcioglu for his interestin our article. In response to the initial question of why exhaustivephysical activity suppresses diastolic function, 相似文献
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Five ileal conduit biopsies, taken after 1-7 years, were examined by light microscopy and scanning electron microscopy. The total height of the lamina mucosa decreased from 700 to 275 microns. The height of the villi diminished from 550 to 50 microns; the depth of the crypts increased from 130 to 244 microns and the villus-crypt index changed from 4.2 to 0.2. Signs of chronic inflammation could be observed. Scanning electron microscopy shows that the number of microvilli per cell was markedly reduced. There was a varied picture of different stages of atrophy. After 3 years microvilli could no longer be observed. In view of the prolonged urinary contamination time, it appears to be imperative to check neobladders with regard to possible carcinoma induction. 相似文献
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Hospital outbreak caused by a carbapenem-resistant strain of Acinetobacter baumannii: patient prognosis and risk-factors for colonisation and infection 总被引:10,自引:0,他引:10
M. del Mar Tomas M. Cartelle S. Pertega A. Beceiro P. Llinares D. Canle F. Molina R. Villanueva J. M. Cisneros G. Bou 《Clinical microbiology and infection》2005,11(7):540-546
Between October 2001 and August 2002, 30 hospital patients became infected or colonised by a multiresistant (including to carbapenems) epidemic strain of Acinetobacter baumannii (AbMR) in a hospital outbreak. This study analysed the risk-factors associated with acquisition of this epidemic strain and investigated the prognosis of patients infected by AbMR, with the aim of elucidating factors which lead to mortality. A case-control study of the acquisition of AbMR in patients infected or colonised in the hospital outbreak was performed. Independent risk-factors leading to death were studied by logistic regression analysis. Multivariate analysis of the risk-factors for colonisation/infection with AbMR revealed an independent association with the presence of an arterial catheter (OR, 1.13; 95% CI, 1.03-1.25) and administration of imipenem as monotherapy (OR, 11.12; 95% CI, 2.33-53.09). Multivariate analysis of the prognostic features leading to mortality revealed a significant association with hypotension or shock (OR, 24.63; 95% CI, 1.56-387.56) at the time of bacterial isolation. 相似文献
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S Hanke H Hanke M Oberhoff K K Haase S Hassenstein E Betz K R Karsch 《Zeitschrift für Kardiologie》1991,80(6):404-411
To determine the time-course of morphological changes after excimer laser treatment of atherosclerotic carotid arteries, laser angioplasty was performed in 34 rabbits after production of an intimal plaque (13 +/- 6 cell layers, 30 +/- 9% stenosis) using electrical stimulations. The animals were sacrificed 3, 7, 14, 21, 28, and 42 days after laser treatment. A total or subtotal thrombotic occlusion was found in four cases. No perforation was observed, but in 10 animals histological examination evidenced a partial ablation of the medial layer with signs of local thrombus formation and local reduction of SMC in the media. In five animals a stenosis of more than 50% of luminal reduction was due to intimal proliferation of smooth muscle cells (SMC), as determined by a monoclonal antibody against alpha-actin. After the initial ablation, a continuous increase of intimal cell layers was found, from 7 +/- 6 cell layers (19 +/- 9% stenosis) at 7 days, to 28 +/- 5 cell layers (45 +/- 18% stenosis) at 28 days following excimer laser angioplasty (p less than 0.01). After 42 days no additional increase of intimal thickening occurred. Our data suggest that incidence and morphology is comparable to the proliferative response of SMC following conventional balloon angioplasty. 相似文献
10.
Dr. Hajo Dirk Weitmann Tomas Hendrik Knocke Claudia Waldhäusl Richard Pötter 《Strahlentherapie und Onkologie》2006,182(2):86-95
BACKGROUND: In advanced vaginal recurrences of cervical and endometrial carcinomas therapeutic options are rare because of preceding therapy. PATIENTS AND METHODS: 23 patients developing advanced vaginal recurrences of cervical and endometrial carcinomas were included. 15 patients started with external-beam therapy to the pelvis and eight patients after preceding radiotherapy underwent brachytherapy alone. All patients had ultrasound-guided implantation of transvaginal or transperineal interstitial needles for brachytherapy. Median prescribed total dose was 64 Gy. RESULTS: 18 patients (78%) achieved complete remission. Six patients are alive without tumor and one with tumor after a median follow-up of 64 months. 14 patients died of tumor and two of intercurrent disease. 5-year disease-specific survival and local control rate were 43% and 47%, respectively, in patients with complete remission. Univariate analysis found time to relapse > 2 years, initial diameter < or = 4 cm, initial volume < 15 cm(3), no extension to the pelvic side wall, volume before brachytherapy < 7.5 cm(3), brachytherapy coverage index > 0.8, and prescribed total dose > 64 Gy being positive predictors for local control and survival. CONCLUSION: The use of ultrasound guidance for placement of interstitial needles in template-based brachytherapy of advanced recurrent gynecologic malignancies is a feasible, safe, and cheap method with encouraging results. Today, ultrasound imaging can be also used to some extent for treatment planning which requires further development. Patient- and treatment-related prognostic factors can be defined. 相似文献