全文获取类型
收费全文 | 609篇 |
免费 | 15篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 37篇 |
妇产科学 | 10篇 |
基础医学 | 49篇 |
口腔科学 | 28篇 |
临床医学 | 63篇 |
内科学 | 212篇 |
皮肤病学 | 23篇 |
神经病学 | 45篇 |
特种医学 | 4篇 |
外科学 | 79篇 |
综合类 | 1篇 |
预防医学 | 70篇 |
眼科学 | 2篇 |
药学 | 25篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 17篇 |
2022年 | 36篇 |
2021年 | 41篇 |
2020年 | 30篇 |
2019年 | 10篇 |
2018年 | 5篇 |
2017年 | 6篇 |
2016年 | 20篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 10篇 |
2012年 | 16篇 |
2011年 | 11篇 |
2010年 | 20篇 |
2009年 | 74篇 |
2008年 | 26篇 |
2007年 | 28篇 |
2006年 | 22篇 |
2005年 | 28篇 |
2004年 | 24篇 |
2003年 | 7篇 |
2002年 | 12篇 |
2001年 | 22篇 |
2000年 | 8篇 |
1999年 | 18篇 |
1998年 | 23篇 |
1997年 | 24篇 |
1996年 | 16篇 |
1995年 | 21篇 |
1994年 | 18篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1985年 | 7篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1975年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有670条查询结果,搜索用时 15 毫秒
41.
Andrea Pacchioni Carlo Angheben Paolo Pellegrini Daniele Prati Marco Turri Maria Antonia Prioli Pierfrancesco Agostoni Andrea Rossi Corrado Vassanelli 《Resuscitation》2009,80(4):493-496
Diagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is often challenging due to differing clinical presentations and unpredictable progression of the disease. We report a case of ARVD/C that presented as cardiac arrest in an 18-year-old male while playing soccer. The electrocardiographic features after resuscitation were typical of anterior ST-segment elevation acute myocardial infarction, and the patient was initially managed accordingly. Importantly, an urgent coronary angiogram revealed completely normal coronary arteries. ARVD/C was first suspected following an echocardiogram, and was later confirmed by cardiac magnetic resonance. One month before the event, the patient had been evaluated for ventricular extrasystoles and an abnormal resting electrocardiogram, however ARVD/C was ruled out because of the presence of only two minor diagnostic criteria (T-wave inversion in anterior precordial leads in the absence of right bundle branch block and more than 1000 ventricular extrasystoles during 24-h Holter monitoring). In consequence, physical activity was not forbidden.In conclusion, this case report enforces the need for a strict prohibition of physical activity and serial evaluation of individuals with only minor diagnostic criteria for ARVD/C, for lacking sensibility of Task Force diagnostic criteria. 相似文献
42.
José G. Dórea 《Clinica chimica acta; international journal of clinical chemistry》2010,411(21-22):1580-1586
ObjectiveTo compare epidemiological studies dealing with neurological issues (compatible with Hg toxicity) linked to exposing newborns and infants to intramuscular doses of preservative-Hg resulting from vaccination with thimerosal-containing vaccines (TCV).MethodsMajor databases were searched for studies that addressed neurodevelopment outcomes other than autism. Eight studies were identified and compared.ResultsInformation extracted from the studies done in the USA, the UK, and Italy is important in understanding the complex interplay of variables but insufficient to establish non-toxicity for infants and young children still receiving TCV: a) there is ambiguity in some studies reporting neurodevelopment outcomes that seem to depend on confounding variables; b) the risk of neurotoxicity due to low doses of thimerosal is plausible at least for susceptible infants; c) there is a need to address these issues in less developed countries still using TCV in pregnant mothers, newborns, and young children.ConclusionsSince the use of TCV is still inevitable in many countries, this increases the need to protect vulnerable infants and promote actions that strengthen neurodevelopment. Developing countries should intensify campaigns that include breastfeeding among efforts to help prime the central nervous system to tolerate exposure to neurotoxic substances, especially thimerosal-Hg. 相似文献
43.
Bethany C. Reeb-Sutherland Ross E. Vanderwert Kathryn A. Degnan Peter J. Marshall Koraly Pérez-Edgar rea Chronis-Tuscano Daniel S. Pine Nathan A. Fox 《Journal of child psychology and psychiatry, and allied disciplines》2009,50(11):1365-1372
Background: Individual differences in specific components of attention contribute to behavioral reactivity and regulation. Children with the temperament of behavioral inhibition (BI) provide a good context for considering the manner in which certain components of attention shape behavior. Infants and children characterized as behaviorally inhibited manifest signs of heightened orienting to novelty. The current study considers whether this attention profile moderates risk for clinical anxiety disorders among adolescents with a history of BI.
Methods: Participants were assessed at multiple time points for BI, beginning in early childhood. At adolescence, event-related potentials (ERPs) were recorded during a three-stimulus auditory novelty oddball task, which employed frequent standard and infrequent deviant tones as well as a set of complex, novel sounds. Clinical diagnosis was carried out using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL). P3 and mismatch negativity (MMN) components were examined at midline frontal, central, and parietal electrode sites.
Results: Individuals who displayed high levels of BI during childhood and increased P3 amplitude to novelty in adolescence were more likely to have a history of anxiety disorders compared to behaviorally inhibited adolescents with lower P3 amplitudes. Groups did not differ on measures of MMN.
Conclusions: Increased neural responses to novelty moderate risk for anxiety disorders amongst individuals with a history of BI. 相似文献
Methods: Participants were assessed at multiple time points for BI, beginning in early childhood. At adolescence, event-related potentials (ERPs) were recorded during a three-stimulus auditory novelty oddball task, which employed frequent standard and infrequent deviant tones as well as a set of complex, novel sounds. Clinical diagnosis was carried out using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL). P3 and mismatch negativity (MMN) components were examined at midline frontal, central, and parietal electrode sites.
Results: Individuals who displayed high levels of BI during childhood and increased P3 amplitude to novelty in adolescence were more likely to have a history of anxiety disorders compared to behaviorally inhibited adolescents with lower P3 amplitudes. Groups did not differ on measures of MMN.
Conclusions: Increased neural responses to novelty moderate risk for anxiety disorders amongst individuals with a history of BI. 相似文献
44.
Mungiu QC Ionescu DG Jaba IM 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2002,106(1):10-13
In the last decade, neurophysiological research regarding nociceptive mediation seems to suggest a possible new approach in pain management--zinc applicability. Immunohistochemical studies prove that zinc can be found in central nervous system, inside structures active in nociception. Zinc stabilizes primary afferent C fibers, nervous fibers involved in nociception. However, this phenomenon is probably only true for extreme zinc concentrations--excess or deficit. Electrophysiological studies indicate that zinc inhibits NMDA receptors, while potentiating the activity of non-NMDA receptors. All these are arguments supporting the existence of a role of endogenous zinc regarding pain transmission. 相似文献
45.
Monounsaturated Fat and Cardiovascular Risk 总被引:2,自引:0,他引:2
Jose López-Miranda MD PhD Lina Badimon PhD rea Bonanome MD PhD Denis Lairon PhD Penny M. Kris-Etherton PhD Pedro Mata MD PhD Francisco Pérez-Jiménez MD PhD 《Nutrition reviews》2006,64(S4):S2-S12
On the basis of the information discussed in this review, we can conclude that the effects of a high intake of monounsaturated fatty acids (MUFA) from olive oil include a wide range of healthy benefits beyond improvement in cholesterol levels, suggesting that this type of diet has great potential in preventing cardiovascular disease. MUFA-enriched diets reduce insulin requirements and decrease plasma concentrations of glucose and insulin in type 2 diabetic patients, unlike high-saturated fatty acid and low-fat, high-carbohydrate diets. Moreover, some data show that this dietary model could have a hypotensive effect. There is also substantial evidence that oleic-enriched low-density lipoprotein (LDL) is more resistant to oxidative modifications and that dietary MUFA may influence various components and functions related to the endothelium. These include endothelium-dependent vasodilatation and a reduced capacity of oleicenriched LDL to promote the adhesion and chemotaxis of monocytes. On the other hand, a MUFA diet decreases the prothrombotic environment, modifying platelet adhesion, coagulation, and fibrinolysis. Its reducing effect on PAI-1 plasma levels is of particular relevance. This wide range of anti-atherogenic effects could explain the low rate of cardiovascular mortality found in Mediterranean countries, where there is a moderate to high supply of dietary MUFA. Future studies need to focus on uncovering the mechanisms by which the Mediterranean diet exerts its beneficial effects 相似文献
46.
Adeyemi Lawal Chris Basler rea Branch Julio Gutierrez Myron Schwartz Thomas D. Schiano 《American journal of transplantation》2004,4(11):1805-1809
Influenza vaccination has reduced life-threatening complications from influenza virus infection in adult liver transplant recipients. We evaluated changes in aminotransferase level and immunogenicity of influenza vaccination in liver transplant recipients. Fifty-one liver transplant recipients were administered a standard dose of the 2002-2003 inactivated trivalent influenza vaccine. ALT values were measured at baseline, 1 week and 4-6 weeks postvaccination. Antibody responses to each component of the vaccine were measured at baseline and after 4-6 weeks by a hemagglutination inhibition (HAI) assay. Response was defined as an HAI titer > or = 1: 40 and/or a 4-fold increase in antibody titers from baseline. An ALT elevation was defined as a rise of > or = 50% from baseline. There was no difference in the median rise in ALT value between seroconverters and nonseroconverters. A significant number of recipients developed potentially protective antibody titers (p-value < 0.0001). At less than 4 months post transplantation, 1/7 (14%), at 4-12 months, 6/9 (67%), and after 12 months, 30/35 (86%) subjects responded to the H1 strain. Of 51 recipients, one HCV (-) recipients vaccinated within 3 months of transplantation developed acute cellular rejection. Influenza virus vaccination is not associated with allograft rejection or ALT flares in liver transplant recipients. 相似文献
47.
Differential Willingness to Undergo Smallpox Vaccination Among African-American and White Individuals
下载免费PDF全文
![点击此处可从《Journal of general internal medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ellyn Micco BA rea D. Gurmankin MA PhD Katrina Armstrong MD MSCE 《Journal of general internal medicine》2004,19(5P1):451-455
OBJECTIVE: To examine potential disparities in willingness to be vaccinated against smallpox among different U.S. racial/ethnic groups.
DESIGN: Cross-sectional survey using an experimental design to assess willingness to be vaccinated among African Americans compared to whites according to 2 strategies: a post-exposure "ring vaccination" method and a pre-exposure national vaccination program.
SETTING: Philadelphia County district courthouse.
PARTICIPANTS: Individuals awaiting jury duty.
MEASUREMENTS: We included 2 scenarios representing these strategies in 2 otherwise identical questionnaires and randomly assigned them to participants. We compared responses by African Americans and whites.
MAIN RESULTS: In the pre-exposure scenario, 66% of 190 participants were willing to get vaccinated against smallpox. In contrast, 84% of 200 participants were willing to get vaccinated in the post-exposure scenario ( P = .0001). African Americans were less willing than whites to get vaccinated in the pre-exposure scenario (54% vs 77%; P = .004), but not in the post-exposure scenario (84% vs 88%; P = .56). In multivariate analyses, overall willingness to undergo vaccination was associated with vaccination strategy (odds ratio, 3.29; 95% confidence interval, 1.8 to 6.1).
CONCLUSIONS: Racial disparity in willingness to get vaccinated varies by the characteristics of the vaccination program. Overall willingness was highest in the context of a post-exposure scenario. These results highlight the importance of considering social issues when constructing bioterror attack response plans that adequately address the needs of all of society's members. 相似文献
DESIGN: Cross-sectional survey using an experimental design to assess willingness to be vaccinated among African Americans compared to whites according to 2 strategies: a post-exposure "ring vaccination" method and a pre-exposure national vaccination program.
SETTING: Philadelphia County district courthouse.
PARTICIPANTS: Individuals awaiting jury duty.
MEASUREMENTS: We included 2 scenarios representing these strategies in 2 otherwise identical questionnaires and randomly assigned them to participants. We compared responses by African Americans and whites.
MAIN RESULTS: In the pre-exposure scenario, 66% of 190 participants were willing to get vaccinated against smallpox. In contrast, 84% of 200 participants were willing to get vaccinated in the post-exposure scenario ( P = .0001). African Americans were less willing than whites to get vaccinated in the pre-exposure scenario (54% vs 77%; P = .004), but not in the post-exposure scenario (84% vs 88%; P = .56). In multivariate analyses, overall willingness to undergo vaccination was associated with vaccination strategy (odds ratio, 3.29; 95% confidence interval, 1.8 to 6.1).
CONCLUSIONS: Racial disparity in willingness to get vaccinated varies by the characteristics of the vaccination program. Overall willingness was highest in the context of a post-exposure scenario. These results highlight the importance of considering social issues when constructing bioterror attack response plans that adequately address the needs of all of society's members. 相似文献
48.
Dórea JG 《Ecotoxicology and environmental safety》2004,57(3):3467-256
The two most important staple foods (cassava and fish) in the diet of native Amazonians contain neurotoxins (linamarin and monomethyl mercury, MMHg). These same neurotoxins are public health issues in other parts of the world. Factors such as chemistry, environment, and human ecology determine the endemism of neuropathies caused by consumption of cassava (Manihot esculenta Crantz) and fish. Linamarin is a natural component of cassava tubers that can be destroyed before consumption by proper processing. Furthermore, small amounts of the toxin absorbed by people consuming cassava can be effectively metabolized if the diet contains adequate protein-containing sulfur amino acids. Naturally occurring Hg in the waters of the Amazonian rain forest is methylated to MMHg by microorganisms and bioconcentrated in the aquatic food chain. There is no effective method for MMHg removal from fish. Despite high concentrations of naturally occurring neurotoxins in cassava (linamarin) and fish (MMHg), daily consumption of these foods in large amounts over the course of a lifetime poses no health hazards for Amazonians. 相似文献
49.
Barbosa AC de Souza J Dórea JG Jardim WF Fadini PS 《Archives of environmental contamination and toxicology》2003,45(2):235-246
The population living along the riverbanks of the Amazon basin depends heavily on fish for nutritional support. Mono-methyl-mercury (MMHg) concentrates in fish, which can contaminate humans, the risk depending not only on fish MMHg concentration but also on the amount of fish consumed. We sampled nine locations of the Rio Negro basin, differing in water pH, Hg concentrations, and dissolved organic carbon (DOC), and determined total Hg from 951 fish samples of species representative of the food web: herbivorous, detritivorous, omnivorous, and piscivorous. Mercury concentrations varied widely in all species but showed a trend that depended on fish feeding strategies. The highest mean concentration was found in the piscivorous species (688.90 ng/g–1), followed by omnivorous (190.30 ng/g–1), detritivorous (136.04 ng/g–1), and herbivorous (70.39 ng/g–1). Fish Hg concentrations exceeding current safe limits (500 ng/g–1) for human consumption were found mainly in the piscivorous species (60%). Significant positive correlation between fish weight and Hg concentration was seen for the piscivorous Serrasalmus spp. (n = 326; r = 0.3977; p < 0.0001), Cichla spp. (n = 125; r = 0.4600; p < 0.0001), and Pimelodus spp. (n = 12; r = 0.8299; p = 0.0008), known locally as Piranha, Tucunaré, and Mandi, respectively. However, a negative correlation was seen for nonpiscivorous Potamorhina latior (n = 30; r –0.3763; p = 0.0404) and Leporinus spp. (n = 44; r = –3987; p = 0.0073), known as Branquinha (detritivorous) and Aracu (omnivorous). Fish-Hg concentrations in the acidic waters (pH range, 4.09–6.31) of the Rio Negro habitat, with its wide gradient of Hg concentrations (3.4–11.9 g/L–1) and DOC (1.85–15.3 mg/L–1)—but no history of gold mining activity—are comparable to other Amazonian rivers. Opportunity fish catches in the Rio Negro habitat show high muscle-Hg derived from natural sources, but no systematic association with site-dependent geochemistry. 相似文献
50.
Socioeconomic status and maternal cigarette smoking before, during and after a pregnancy 总被引:2,自引:0,他引:2
Jake M. Najman rea Lanyon Margaret Andersen Gail Williams William Bor Michael O'Callaghan 《Australian and New Zealand journal of public health》1998,22(1):60-66
Abstract: Research suggests that cigarette use declines when women find out they are pregnant, increasing again after the birth. Pregnancy may provide many women with a substantial impetus to stopping smoking. Also, rates of smoking cessation and reduction may be class-related, with the highest socioeconomic-status groups manifesting higher rates of reduction. Using data from the Mater Hospital-University of Queensland Study of Pregnancy, we report family income related to rates of smoking before, during and after a pregnancy. Before becoming pregnant, 45.9 per cent of women in the sample were smokers. This declined to 34.7 per cent of women at their first clinic visit. Rates of heavy smoking (20 or more cigarettes per day) had returned to earlier levels by the six-month (after birth) follow-up. Women in the lowest family-income group had the highest rates of cigarette use before, during and after their pregnancy. Of the lowest family-income group, 8.4 per cent were heavy smokers before, during and after their pregnancy, compared with 2.8 per cent of women in the highest family-income group. Smoking cessation rates were highest in the highest family-income group (those who smoked least), but relapse rates after the birth were similar for all income groups. Arresting rates of smoking relapse by pregnant women should be seen as a major public health priority 相似文献