全文获取类型
收费全文 | 4562篇 |
免费 | 254篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 134篇 |
妇产科学 | 95篇 |
基础医学 | 597篇 |
口腔科学 | 117篇 |
临床医学 | 415篇 |
内科学 | 1228篇 |
皮肤病学 | 82篇 |
神经病学 | 520篇 |
特种医学 | 126篇 |
外科学 | 434篇 |
综合类 | 14篇 |
一般理论 | 3篇 |
预防医学 | 234篇 |
眼科学 | 100篇 |
药学 | 302篇 |
中国医学 | 5篇 |
肿瘤学 | 436篇 |
出版年
2024年 | 8篇 |
2023年 | 54篇 |
2022年 | 154篇 |
2021年 | 234篇 |
2020年 | 142篇 |
2019年 | 157篇 |
2018年 | 178篇 |
2017年 | 106篇 |
2016年 | 131篇 |
2015年 | 181篇 |
2014年 | 197篇 |
2013年 | 238篇 |
2012年 | 370篇 |
2011年 | 379篇 |
2010年 | 211篇 |
2009年 | 191篇 |
2008年 | 272篇 |
2007年 | 228篇 |
2006年 | 239篇 |
2005年 | 189篇 |
2004年 | 168篇 |
2003年 | 175篇 |
2002年 | 138篇 |
2001年 | 54篇 |
2000年 | 63篇 |
1999年 | 38篇 |
1998年 | 22篇 |
1997年 | 11篇 |
1996年 | 15篇 |
1995年 | 14篇 |
1994年 | 6篇 |
1993年 | 10篇 |
1992年 | 23篇 |
1991年 | 27篇 |
1990年 | 14篇 |
1989年 | 30篇 |
1988年 | 20篇 |
1987年 | 22篇 |
1986年 | 14篇 |
1985年 | 19篇 |
1984年 | 13篇 |
1983年 | 12篇 |
1982年 | 6篇 |
1979年 | 9篇 |
1977年 | 7篇 |
1976年 | 9篇 |
1973年 | 7篇 |
1971年 | 5篇 |
1970年 | 6篇 |
1968年 | 9篇 |
排序方式: 共有4861条查询结果,搜索用时 31 毫秒
91.
Krengli Marco Ferrara Eleonora Guaschino Riccardo Puta Erinda Turri Lucia Luciani Ilaria Sacchetti Gian Mauro Franco Pierfrancesco Brambilla Marco 《Annals of nuclear medicine》2022,36(5):450-459
Annals of Nuclear Medicine - [18F] fluorodeoxyglucose positron emission tomography/computed tomography ([18F] FDG-PET/CT) is used for diagnosis, staging, response assessment and prognosis... 相似文献
92.
93.
Casorati G Locatelli F Pagani S Garavaglia C Montini E Lisini D Turin I Rossi F Dellabona P Maccario R Montagna D 《Experimental hematology》2005,33(2):212-218
OBJECTIVE: Studies of memory T cells transferred with the graft are relevant to better understand the early immune reconstitution of patients given autologous bone marrow transplantation (A-BMT). A critical question is whether memory T cells resident in bone marrow (BM) of patients with hematological malignancies are resistant to either pretransplant chemotherapy or ex vivo pharmacological purging. PATIENTS AND METHODS: To address these issues, we evaluated the frequency of tetanus-toxoid (TT)-specific proliferating T-cell precursors (TT-PTCp) in BM and peripheral blood (PB) of eight patients with acute myeloid leukemia (AML) given A-BMT after in vitro purging of BM with mafosfamide. Patients were studied at the time of BM harvesting and five of them also after A-BMT. RESULTS: The range of TT-PTCp frequencies found after A-BMT were comparable with those observed in PB and in BM at the time of harvesting and did not differ significantly from those of eight age-matched healthy subjects who donated BM for a human leukocyte antigen-identical sibling. TT-PTCp frequencies in BM, studied before and after ex vivo purging, appeared not to be affected by incubation with mafosfamide. We also compared the T-cell receptor (TCR)-Vbeta-repertoire usage of TT-specific T-cell lines (TT-TCL) in BM of patients at the time of harvesting and in their PB 2 months after transplantation. The same TCR-clonotypes were detected in TT-TCL at time of harvesting and after A-BMT. CONCLUSION: These data indicate that BM-resident memory T cells of patients with AML are resistant to both pretransplant chemotherapy and ex vivo pharmacological purging and may contribute to immune reconstitution after A-BMT. 相似文献
94.
Visiting Professor of Biochemistry Y. B. Lombardo W. T. Hron L. A. Menahan 《Diabetologia》1978,14(1):47-51
Summary Withdrawal of exogenous insulin and a subsequent fast (24 h) of alloxan diabetic rats stimulated rates of gluconeogenesis, ureogenesis, ketogenesis, and amino acid release by in situ perfused livers when compared to those from normal, fasted rats. The contribution of liver glycogen to the high rates of gluconeogenesis observed with the diabetic liver could be excluded. Perfusate lactate concentrations remained constant during the period when the elevated rate of gluconeogenesis was observed with diabetic liver. Addition of insulin as a bolus (750 mU) and continuous infusion (12.5 mU/min) to the perfusion medium of diabetic livers resulted in constant perfusate levels of glucose, urea and -amino nitrogen indicating a suppression of the catabolic processes present in the fasted, diabetic liver. The rate of ketogenesis was also slowed by insulin to about half the rate prior to addition of the hormone. These data indicate that insulin has an immediate anti-catabolic effect in the perfused, diabetic liver. 相似文献
95.
96.
H S Besterman T E Adrian S R Bloom N D Christofides C N Mallinson V Ponti L Lombardo R Modigliani S Guerin M South 《Digestion》1982,24(3):195-208
Pancreatic and gut hormones have been measured in 39 patients with chronic pancreatitis, 16 of whom had severe pancreatic insufficiency. Patients with pancreatic insufficiency had significantly diminished fasting levels and postprandial rises of pancreatic polypeptide which were less than 20% of normal. Patients with chronic pancreatitis, with or without exocrine insufficiency, had two- to threefold higher plasma levels of motilin and enteroglucagon than controls. Plasma levels of insulin, pancreatic glucagon, gastric inhibitory polypeptide and gastrin were similar to normal in these patients. The pattern of response of these hormones to a test breakfast differs markedly from those seen in other gut disease states and may reflect pathophysiological mechanisms. 相似文献
97.
Paolo Ditonno Roberto Ria Ilaria Marech Annunziata De Luisi Simona Berardi Maria Antonia Frassanito Emanuele Angelucci Daniele Derudas Giorgina Specchia Paola Curci Vincenzo Pavone Bernardo Rossini Domenico Ribatti Barbara Bottazzi Alberto Mantovani Marco Presta Franco Dammacco Angelo Vacca 《The Journal of pathology》2013,229(1):87-98
Pentraxin 3 (PTX3) is a soluble pattern recognition receptor that binds with high affinity and selectivity to fibroblast growth factor‐2 (FGF2), thus inhibiting its pro‐angiogenic activity. Here we investigated the effects of PTX3 on monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patient‐derived bone marrow (BM) plasma cells (PCs), endothelial cells (ECs), and fibroblasts (FBs), and assessed whether PTX3 can modulate the cross‐talk between PCs and those microenvironment cells. PTX3 and FGF2 expression was evaluated by ELISA. Functional studies, including cell viability, wound healing, chemotaxis, and Matrigel® assays, were performed on MGUS and MM ECs and FBs upon the PTX3 treatment. Through western blot PTX3‐induced modulation in FGF2/FGF receptor signalling pathways was evaluated in MGUS and MM ECs and FBs through western blot. Co‐cultures between MM ECs/FBs and human PC lines were used to evaluate possible PTX3 indirect effects on MM PCs. Adhesion molecules were studied by flow cytometry. PTX3 provides a direct time‐ and dose‐dependent apoptotic effect on MM ECs and FBs, but not on either MM primary PCs or human PC lines. PTX3 inhibits migration of MM ECs and FBs in a dose‐dependent manner, and impacts in vitro and in vivo FGF2‐mediated MM angiogenesis. Co‐cultures of PCs and ECs/FBs show that PTX3 treatment indirectly impairs PC viability and adhesion. We conclude that PTX3 is an anti‐angiogenic factor in MM and behaves as a cytotoxic molecule on MM cells by inhibiting the cross‐talk between PCs and ECs/FBs. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
98.
Caroline Mann Tim Schfer Anke Bletsch Maria Gudbrandsen Eileen Daly John Suckling Edward T. Bullmore Michael V. Lombardo MengChuan Lai Michael C. Craig MRC AIMS Consortium Simon BaronCohen Declan G.M. Murphy Christine Ecker 《Human brain mapping》2021,42(4):953
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is accompanied by neurodevelopmental differences in regional cortical volume (CV), and a potential layer‐specific pathology. Conventional measures of CV, however, do not indicate how volume is distributed across cortical layers. In a sample of 92 typically developing (TD) controls and 92 adult individuals with ASD (aged 18–52 years), we examined volumetric gradients by quantifying the degree to which CV is weighted from the pial to the white surface of the brain. Overall, the spatial distribution of Frustum Surface Ratio (FSR) followed the gyral and sulcal pattern of the cortex and approximated a bimodal Gaussian distribution caused by a linear mixture of vertices on gyri and sulci. Measures of FSR were highly correlated with vertex‐wise estimates of mean curvature, sulcal depth, and pial surface area, although none of these features explained more than 76% variability in FSR on their own. Moreover, in ASD, we observed a pattern of predominant increases in the degree of FSR relative to TD controls, with an atypical neurodevelopmental trajectory. Our findings suggest a more outward‐weighted gradient of CV in ASD, which may indicate a larger contribution of supragranular layers to regional differences in CV. 相似文献
99.
ObjectivesThis review explores the literature about the status and influence of statutory regulation in healthcare with a focus on medical imaging. It summarises the status of regulation in Australia for radiographers and sonographers, with brief reference to the global situation. The role of regulation is explored in terms of its evolution, function and effect on professional behaviours.Key findingsReports of medical errors, sentinel events and professional misconduct in healthcare have raised concern about how health care professionals are regulated. Patient-centric healthcare delivery has changed how people interact with healthcare, contributing to the development of statutory regulation for many healthcare professions.In Australia, the Health Practitioner Regulation National Law (The National Law) 2009, established the National Registration and Accreditation Scheme (NRAS) in order to practice. Not all health care professions are included in the scheme. In medical imaging, radiographers are included but sonographers are a notable exception.Regulation is designed to positively influence practitioners' professional behaviours. The available evidence however is limited, but suggests that under certain circumstances, it can negatively impact practitioners’ professional behaviours.ConclusionStatutory regulation has been implemented to address serious issues highlighted in reports of medical errors and professional misconduct, but it may have unintended consequences on the professional behaviours of practitioners. Limited research means the relationship between statutory regulation of healthcare practitioners and its impact upon professional behaviours remains unclear.Implications for practiceIf statutory regulation of healthcare professionals is to achieve its aim of protecting the public, it is imperative that we understand the impact that it has on professional behaviours. This review highlights that it can negatively impact professional behaviours which may be detrimental to patient's safety. 相似文献
100.
De Matteis Eleonora Affaitati Giannapia Frattale Ilaria Caponnetto Valeria Pistoia Francesca Giamberardino Maria Adele Sacco Simona Ornello Raffaele 《Neurological sciences》2021,42(8):3297-3303
Neurological Sciences - Monoclonal antibodies targeting the calcitonin gene-related peptide, including erenumab, are migraine-specific preventive treatments, whose long-term effectiveness has still... 相似文献