全文获取类型
收费全文 | 3280篇 |
免费 | 162篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 52篇 |
妇产科学 | 65篇 |
基础医学 | 339篇 |
口腔科学 | 112篇 |
临床医学 | 233篇 |
内科学 | 811篇 |
皮肤病学 | 23篇 |
神经病学 | 320篇 |
特种医学 | 89篇 |
外科学 | 699篇 |
综合类 | 9篇 |
预防医学 | 131篇 |
眼科学 | 20篇 |
药学 | 127篇 |
中国医学 | 3篇 |
肿瘤学 | 415篇 |
出版年
2024年 | 3篇 |
2023年 | 18篇 |
2022年 | 40篇 |
2021年 | 102篇 |
2020年 | 66篇 |
2019年 | 102篇 |
2018年 | 87篇 |
2017年 | 91篇 |
2016年 | 75篇 |
2015年 | 106篇 |
2014年 | 121篇 |
2013年 | 188篇 |
2012年 | 249篇 |
2011年 | 225篇 |
2010年 | 143篇 |
2009年 | 152篇 |
2008年 | 224篇 |
2007年 | 213篇 |
2006年 | 206篇 |
2005年 | 212篇 |
2004年 | 186篇 |
2003年 | 168篇 |
2002年 | 137篇 |
2001年 | 35篇 |
2000年 | 8篇 |
1999年 | 25篇 |
1998年 | 28篇 |
1997年 | 25篇 |
1996年 | 24篇 |
1995年 | 13篇 |
1994年 | 14篇 |
1993年 | 13篇 |
1992年 | 16篇 |
1991年 | 8篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1988年 | 6篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 6篇 |
1984年 | 11篇 |
1983年 | 7篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 14篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1974年 | 3篇 |
1973年 | 3篇 |
排序方式: 共有3474条查询结果,搜索用时 15 毫秒
81.
82.
Giorgio Minoli M.D. Vittorio Terruzzi M.D. Gianni Imperiali M.D. Guido Frigerio M.D. Enrico Colombo M.D. Umberto Comin M.D. Giuseppe Corsini M.D. Marcello Curzio M.D. Alberto Prada M.D. Francesco Rocca M.D. Renato Venturelli M.D. Andrew Kenneth Burroughs M.D. 《The American journal of gastroenterology》1994,89(1):72-78
Objective : To evaluate if tbere was periodicity in the manifestations of gastrointestinal bleeding (hemateme-sis and melena). Method : This is a multicenter prospective study carried out in the Endoscopy Units of eight hospitals. At the time of the emergency endoscopy, the following data were collected: age, sex, endoscopic diagnosis, solar hour of the first hematemesis (vomiting of bright red or tarry black material) and of the first melena (black or bloody soft stools), and any drugs taken during the week before the bleeding episode, regardless of the dose. Results : 806 patients were studied. Bleeding was from peptic ulcer in 405 patients (50%), from esophageal varices in 197 (24%), and from other sources in the remainder. Analysis using single cosinor statistics showed a nonrandom distribution in bleeding from peptic ulcer, whether presenting first with hematemesis (p = 0.02) or melena (p = 0.03). There were two peaks at 6:45 AM and 6:45 PM for hemate-mesis and at 7:25 AM and 7:25 PM for melena, representing a biphasic diurnal (ultradian) rhythm. Conclusions : This study shows that bleeding due to peptic ulcer has a biphasic diurnal periodicity. 1 his has potential importance for the pathogenesis of bleeding, for the management of gastrointestinal hemorrhage and the administration of drugs known to cause peptic ulcer bleeding. 相似文献
83.
Hepatocellular carcinoma in HIV-infected patients: epidemiological features, clinical presentation and outcome 总被引:4,自引:0,他引:4
Puoti M Bruno R Soriano V Donato F Gaeta GB Quinzan GP Precone D Gelatti U Asensi V Vaccher E;HIV HCC Cooperative Italian-Spanish Group 《AIDS (London, England)》2004,18(17):2285-2293
OBJECTIVE: Hepatocellular carcinoma (HCC) is an increasing cause of mortality in HIV-seropositive individuals. The aim of the study was to compare the main features of HCC in HIV-seropositive individuals with those in to HIV-negative patients. PATIENTS AND METHODS: All HIV-infected subjects with a diagnosis of HCC included in three cancer registry databases were enrolled in the study as cases. HCC cases that occurred in the province of Brescia, North Italy, in the period 1995-1998 and all cases reported at the Italian Liver Cancer Project were enrolled as controls. All data were collected using a standardized case report form. The main clinical and epidemiological characteristics of patients with HCC and their survival were compared between HIV-positive and uninfected subjects. RESULTS: Forty-one HIV-infected subjects with HCC were identified. Multivariate analysis adjusted for age and sex identified an association between HIV infection and HCV infection [odds ratio (OR), 11; P = 0.005], and infiltrating tumours and/or extranodal metastasis at presentation (OR = 11.8; P < 0.001). HIV infection was independently associated with shorter survival (hazard ratio, 1.63; P = 0.015). CONCLUSIONS: HCC in HIV-infected patients is mainly associated with underlying chronic hepatitis C and has a more aggressive clinical course. Thus, preventative strategies (including the treatment of hepatitis C) should be implemented in the management of HIV/HCV-coinfected patients. 相似文献
84.
85.
Laurence P. Diggs Benjamin Ruf Chi Ma Bernd Heinrich Linda Cui Qianfei Zhang John C. McVey Simon Wabitsch Sophia Heinrich Umberto Rosato Walter Lai Varun Subramanyam Thomas Longerich Sven H. Loosen Tom Luedde Ulf Peter Neumann Sabina Desar David Kleiner Tim F. Greten 《Journal of hepatology》2021,74(5):1145-1154
- Download : Download high-res image (164KB)
- Download : Download full-size image
86.
Frequency of O6‐methylguanine‐DNA methyltransferase promoter methylation in cytological samples from small cell lung cancer
下载免费PDF全文
![点击此处可从《Diagnostic cytopathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Umberto Miglio Ph.D Rosanna Mezzapelle Ph.D Alessia Paganotti B.Sc. Claudia Veggiani B.Sc. Francesca Mercalli M.D. Giuseppe Mancuso M.Sc. Erica Gaudino M.D. Ottavio Rena Ph.D Roberta Buosi M.D. Renzo Boldorini M.D. 《Diagnostic cytopathology》2015,43(11):947-952
Background. In a phase II study for patients with relapsed small cell lung cancer (SCLC), the administration of Temozolomide, an alkylating agent used in gliomas and anaplastic astrocytoma, showed a effective activity when O6‐methylguanine‐DNA methyltransferase (MGMT) gene promoter was methylated. Methods. We tested the feasibility of MGMT promoter status evaluation in small biopsies and cytological specimens routinely processed for diagnostic purposes. We tested samples from 56 patients with SCLC: 30 tissue biopsies, 17 fine‐needle aspiration biopsy, 8 bronchial washing, and 1 was a sputum. Biopsies and fine‐needle aspiration biopsy were fixed in formalin, bronchial washing and sputum in Dubosq Brazil. DNA was extracted after macrodissection of the areas containing the maximum number of cancer cells. MGMT promoter methylation status was assessed by methylation specific PCR. Results. Methylation analysis was obtained in 54 samples (54/56) and failed in two bronchial wash. MGMT promoter was methylated in 35.2% of the cases without any significant difference between histological and cytological samples (37.9% vs. 32%). Conclusion. MGMT promoter methylation is present in SCLC and cytological samples are perfectly adequate for methylation analysis, even if they were taken during routine diagnostic procedures, using different fixative and with low number and percentage of cancer cells. Diagn. Cytopathol. 2015;43:947–952. © 2015 Wiley Periodicals, Inc. 相似文献
87.
Mario Santagata Umberto Tozzi Ettore Lamart Gianpaolo Tartaro 《Journal of maxillofacial and oral surgery》2015,14(3):682-686
Introduction
Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient’s life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions.Materials and methods
This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery.Conclusion
The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only. 相似文献88.
89.
Mario Iannaccone Mohamed Abdirashid Umberto Annone Gaëlle Saint‐Hilary Pascal Meier Alaide Chieffo Sl Chen Carlo di Mario Federico Conrotto Pierluigi Omed Antonio Montefusco Michele De Benedictis Sara Rettegno Baldassare Doronzo Mauro Gasparini Mauro Rinaldi Maurizio D'Amico Fabrizio D'Ascenzo 《Catheterization and cardiovascular interventions》2020,95(7):1259-1266
90.
One-hundred patients were included to evaluate the role of cerebral computed tomography (CT) to improve patient selection in asymptomatic internal carotid stenosis. Symptomatic patients were assigned to group A, asymptomatic patients to group B. A cerebral CT pattern A was observed in groups A and B in 60% and 20%, respectively (P < .0001). Between A and B groups, type 6 plaques were found, respectively, in 26.7% and 7.5% of patients (P = .01); a type 5 in 51.7% and 45% (P = .32) of patients; and a type 4 in 21.7% and 47.5% of patients, respectively (P = .006). Within B group, the association of CT pattern A and histological plaque level 4, 5, and 6 was, respectively, 25% (P = .15), 50% (P = .53), and 25% (P = .16). In group B, a 7-fold risk increase in CT pattern A was found in patients with level 6 plaque. In asymptomatic patients with high-risk plaque, a basal cerebral CT scan can be used as diagnostic tool to improve patient selection for intervention. 相似文献