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961.
Disposition of d‐penicillamine,a promising drug for preventing alcohol‐relapse. Influence of dose,chronic alcohol consumption and age: studies in rats
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Alejandro Orrico Lucía Martí‐Prats M. José Cano‐Cebrián Ana Polache Teodoro Zornoza Luis Granero 《Biopharmaceutics & drug disposition》2014,35(5):284-295
Pharmacokinetic studies concerning d ‐penicillamine (an acetaldehyde sequestering agent) are scarce and have not evaluated the influence of chronic ethanol consumption and age on its disposition. Since recent preclinical studies propose d ‐penicillamine as a promising treatment for alcohol relapse, the main aim of the present work was to evaluate the influence of these two factors on d ‐penicillamine disposition in order to guide future clinical studies on the anti‐relapse efficacy of this drug in alcoholism. Additionally, the effect of the administered dose was also evaluated. To this end, three studies were carried out. Study 1 assessed the influence of dose on d ‐penicillamine disposition, whereas studies 2 and 3 evaluated, respectively, the influence of chronic alcohol consumption and age. Rapid intravenous administrations of 2, 10 and 30 mg/kg of d ‐penicillamine were performed using young or adult ethanol‐naïve rats or adult ethanol‐experienced (subjected to a long‐term ethanol self‐administration protocol) rats. Pharmacokinetic parameters were derived from the biexponential model. Statistical analysis of CL, normalized AUC0∞, V1 and k10 revealed that disposition, in the range plasma concentrations assayed, is non‐linear both in young ethanol‐naïve and in adult ethanol‐experienced rats. Notably, no significant changes in t1/2 were detected. Chronic ethanol consumption significantly reduced CL values by 35% without affecting t1/2. d ‐Penicillamine disposition was equivalent in young and adult animals. In conclusion, although DP pharmacokinetics is non‐linear, the lack of significant alterations of the t1/2 would potentially simplify the clinical use of this drug. Chronic consumption of ethanol also alters d ‐penicillamine disposition but, again, does not modify t1/2. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
962.
J. Alfredo Martínez Fermín I. Milagro Kate J. Claycombe Kevin L. Schalinske 《Advances in nutrition (Bethesda, Md.)》2014,5(1):71-81
Given the role that diet and other environmental factors play in the development of obesity and type 2 diabetes, the implication of different epigenetic processes is being investigated. Although it is well known that external factors can cause cell type-dependent epigenetic changes, including DNA methylation, histone tail modifications, and chromatin remodeling, the regulation of these processes, the magnitude of the changes and the cell types in which they occur, the individuals more predisposed, and the more crucial stages of life remain to be elucidated. There is evidence that obese and diabetic people have a pattern of epigenetic marks different from nonobese and nondiabetic individuals. The main long-term goals in this field are the identification and understanding of the role of epigenetic marks that could be used as early predictors of metabolic risk and the development of drugs or diet-related treatments able to delay these epigenetic changes and even reverse them. But weight gain and insulin resistance/diabetes are influenced not only by epigenetic factors; different epigenetic biomarkers have also been identified as early predictors of weight loss and the maintenance of body weight after weight loss. The characterization of all the factors that are able to modify the epigenetic signatures and the determination of their real importance are hindered by the following factors: the magnitude of change produced by dietary and environmental factors is small and cumulative; there are great differences among cell types; and there are many factors involved, including age, with multiple interactions between them. 相似文献
963.
Michael Marks Pere Millat-Martinez Dan Ouchi Chrissy h Roberts Andrea Alemany Marc Corbacho-Monné Maria Ubals Aurelio Tobias Cristian Tebé Ester Ballana Quique Bassat Bàrbara Baro Martí Vall-Mayans Camila G-Beiras Nuria Prat Jordi Ara Bonaventura Clotet Oriol Mitjà 《The Lancet infectious diseases》2021,21(5):629-636
964.
965.
966.
T-cell repopulation and thymic volume in HIV-1-infected adult patients after highly active antiretroviral therapy 总被引:4,自引:2,他引:4
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Franco JM Rubio A Martínez-Moya M Leal M Merchante E Sánchez-Quijano A Lissen E 《Blood》2002,99(10):3702-3706
The origin of T cells after highly active antiretroviral therapy (HAART) in patients infected with human immunodeficiency virus 1 (HIV-1) is now under discussion. The possibility of renewed lymphopoiesis in aged thymuses is still controversial. In this work we combine the analysis of na?ve T cells, T-cell receptor excision circles (TRECs), and computed tomography scanning of thymic tissue to further assess whether the thymus is involved in immune reconstitution. Fifteen antiretroviral-na?ve HIV-1-infected patients were evaluated during 48 weeks of HAART. At baseline, significant correlation was present among age and both thymic volume and TRECs, and between na?ve T cells and TRECs. After starting HAART, there was a significant increase at week 12 in na?ve CD4(+) and CD8(+) T cells, TRECs, and thymic volume. The initial net increases in na?ve T cells and TREC counts were significantly correlated. Changes in thymic volume and TRECs were also indirectly related; splitting the population into 2 groups of high and low baseline TREC levels, only the group with low TREC levels had significant increases in both TRECs and thymic volume. Thus, the increase in thymic volume might be functional, in response to depleted TREC levels. Taken together, our data strongly suggest a thymic role in immune reconstitution, at least in patients with depleted baseline TREC levels. (Blood. 2002;99:3702-3706) 相似文献
967.
Luis David Alcaraz Gabriela Olmedo Germán Bonilla René Cerritos Gustavo Hernández Alfredo Cruz Enrique Ramírez Catherine Putonti Beatriz Jiménez Eva Martínez Varinia López Jacqueline L. Arvizu Francisco Ayala Francisco Razo Juan Caballero Janet Siefert Luis Eguiarte Jean-Philippe Vielle Octavio Martínez Valeria Souza Alfredo Herrera-Estrella Luis Herrera-Estrella 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(15):5803-5808
The Cuatro Ciénegas Basin (CCB) in the central part of the Chihuahan desert (Coahuila, Mexico) hosts a wide diversity of microorganisms contained within springs thought to be geomorphological relics of an ancient sea. A major question remaining to be answered is whether bacteria from CCB are ancient marine bacteria that adapted to an oligotrophic system poor in NaCl, rich in sulfates, and with extremely low phosphorus levels (<0.3 μM). Here, we report the complete genome sequence of Bacillus coahuilensis, a sporulating bacterium isolated from the water column of a desiccation lagoon in CCB. At 3.35 Megabases this is the smallest genome sequenced to date of a Bacillus species and provides insights into the origin, evolution, and adaptation of B. coahuilensis to the CCB environment. We propose that the size and complexity of the B. coahuilensis genome reflects the adaptation of an ancient marine bacterium to a novel environment, providing support to a “marine isolation origin hypothesis” that is consistent with the geology of CCB. This genomic adaptation includes the acquisition through horizontal gene transfer of genes involved in phosphorous utilization efficiency and adaptation to high-light environments. The B. coahuilensis genome sequence also revealed important ecological features of the bacterial community in CCB and offers opportunities for a unique glimpse of a microbe-dominated world last seen in the Precambrian. 相似文献
968.
969.
María Martínez García Pablo Trincado Aznar Leticia Pérez Fernández Isabel Azcona Monreal María Elena López Alaminos Javier Acha Pérez Ramón Albero Gamboa 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2019,39(1)
Introduction
Both dietary restriction of sodium chloride (NaCl) and treatment with thiazides have been used in hypercalciuric patients.Objectives
To calculate regular salt intake and investigate the correlation between natriuresis and urinary calcium with usual diet (B) and after changing the amount of NaCl intake and administration of thiazides.Material and methods
Nineteen healthy young individuals had their diet replaced by 2 l of Nutrison® Low Sodium (500 mg sodium/day) daily for two days. Then, 5 g of NaCl were added every two days («5», «10» and «15»), administering 50 mg (H50) and 100 mg (H100) of Higroton® on the last two days. Blood sodium, plasma renin activity (PRA) and aldosterone were determined in venous blood samples, as were urinary sodium and calcium. Statistical analysis: Wilcoxon t-test and the Pearson linear correlation were calculated.Results
Urinary Na (mEq/24 h): 210.3 ± 87.6 («B»); 42.7 ± 20.4 («5»); 135.5 ± 50.6 («10»); 225.5 ± 56.7 («15»). Urinary calcium (mg/24 h): 207.8 ± 93.6 («B»); 172.8 ± 63.1 («5»); 206.2 ± 87.7 («10»); 227.4 ± 84.1 («15»). A positive correlation was observed between natriuresis and urinary calcium in «10» (r = 0.47) and «15» (r = 0.67). After Higroton®, natriuresis: 232.3 ± 50.7; 377 ± 4 (H50); 341.1 ± 68.4 (H100); Ca in urine: 209.8 ± 57.4; 213.2 ± 67.6 (H50); 159.1 ± 52.2 (H100).Conclusions
Salt intake in the population studied was estimated to be 14.9 ± 4.9 g/day with a positive correlation found between sodium and calcium urine output with daily intakes of 11.25 and 16.25 g of salt. With the usual intake, for each gram of salt, urinary calcium increased by 5.46 mg/24 h and with 100 mg of Higroton® it decreased by 50.7 mg/24 h. These data could be useful for the management of patients with excretory hypercalciuria or hypoparathyroidism. 相似文献970.
L R Rábago Torre F Gea Rodríguez P Mora Sanz P Martínez Montiel F Soler Grande C Paniagua Gómez-Alvarez R Campos Cantero 《Revista española de enfermedades digestivas》1992,81(3):200-203
A 65-year-old man was admitted to our hospital with gastrointestinal bleeding. Seventeen years previously, he had a Billroth II procedure for a bleeding duodenal ulcer. A gastroscopy performed on admission showed a stomal ulcer with signs of recent haemorrhage. In the proximal end of the afferent loop, we saw retained gastric mucosa. Histological evaluation confirmed the existence of antrum gastric mucosa. Other diagnostic test for retained gastric antrum were normal. The different approaches in the diagnosis of retained gastric antrum, the importance of our findings and the clinic implications are discussed. We conclude that endoscopic management may be the first diagnostic method in the assessment of retained gastric antrum, and it's possible to find gastric mucosa in the proximal end of the afferent loop (antrum retained), without clinic manifestations. 相似文献