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排序方式: 共有1222条查询结果,搜索用时 0 毫秒
1.
Candice A Bookwalter Mark A Griswold Jeffrey L Sunshine Jeffrey L Duerk 《Magnetic resonance in medicine》2007,58(4):819-824
Image signal-to-noise ratio (SNR) limits many MRI applications. Here we propose a method to improve SNR based on continuous sampling (CS) during each TR without significant increases in acquisition time. The general concept of CS is defined here as sampling the NMR signal immediately after slice excitation including ramp times, both the dephase and rephase lobes, the phase-encoding (PE) gradient application, and the slice refocusing gradient. This study analyzes several cases of CS and demonstrates a specific case where sampling occurs during an isolated and balanced readout gradient in order to increase SNR in a rectilinear Cartesian sequence without significantly increasing overall acquisition time. The noise correlation consequences of rectilinear CS are mathematically derived and proven through simulation. The SNR improvement of up to approximately 40% measured in both phantom and asymptomatic human volunteer images is comparable to theoretical prediction of increased SNR proportional to the increase in the square root of the sampling time. 相似文献
2.
Belanoff Candice Alade Mayowa Oluwatosin Almeida Joanna 《Maternal and child health journal》2022,26(4):834-844
Maternal and Child Health Journal - Foreign-born non-Hispanic Black (NHB) birthing parents are less likely to have a preterm birth (PTB) than US-born NHBs. There is further variation by region and... 相似文献
3.
Bateni Sarah B. Gingrich Alicia A. Kirane Amanda R. Sauder Candice A. M. Gholami Sepideh Bold Richard J. Meyers Frederick J. Canter Robert J. 《Annals of surgical oncology》2021,28(3):428-428
Annals of Surgical Oncology - 相似文献
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Marcelo Borges Cavalcante Candice Torres de Melo Bezerra Cavalcante Ana Catherine Sampaio Braga Dennyse Araújo Andrade Mariana Albuquerque Montenegro Paula Andrade Neiva Santos Paula Vitria Pereira Motoyama Marcelo Gondim Rocha Luciana Azr Dib Edward Araujo Júnior 《Geburtshilfe und Frauenheilkunde》2021,81(1):46
In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding 相似文献
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Thomas N Ferraro Gregory T Golden George G Smith James F Martin Candice L Schwebel Glenn A Doyle Russell J Buono Wade H Berrettini 《Neuropsychopharmacology》2005,30(4):742-746
C57BL/6 (B6) and DBA/2 (D2) mice exhibit disparate behavior when tested for voluntary morphine intake in a two-bottle choice drinking paradigm with B6 mice consuming 10 times more drug than D2 mice. Previous genetic mapping studies identified a locus, Mop2, on the proximal part of chromosome 10 that explained over half of the genetic variance in this mouse model of opioid self-administration. We constructed a set of reciprocal congenic strains between B6 and D2 mice in which the proximal portion of chromosome 10 has been introgressed from one strain onto the background of the other. We tested mice from this pair of reciprocal strains together with progenitor B6 and D2 mice in a two-bottle choice drinking paradigm with morphine and quinine. The results showed that introgression of chromosome 10 alleles from the B6 strain onto a D2 genetic background increased voluntary morphine intake four-fold compared to progenitor D2 mice. Preference for morphine was also increased significantly in D2.B6-Mop2 mice compared to progenitor D2 mice. Conversely, introgression of chromosome 10 alleles from the D2 strain onto a B6 genetic background decreased morphine intake by half compared to progenitor B6 mice in B6.D2 -Mop2 mice; however, high morphine preference was maintained in this congenic strain most likely due to strong quinine aversion. When quinine was eliminated from the control bottle, morphine preference in B6.D2-Mop2 mice was decreased significantly relative to B6 and D2.B6-Mop2 mice. Overall, these data confirm the existence of a gene(s) on chromosome 10 proximal to D10Mit124 that has a strong influence on the difference in morphine drinking behavior between B6 and D2 mice. 相似文献
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Quantification in Patient Urine Samples of Felbamate and Three Metabolites: Acid Carbamate and Two Mercapturic Acids 总被引:1,自引:0,他引:1
Charles D. Thompson Mary T. Barthen Darrin W. Hopper Thomas A. Miller Mark Quigg Candice Hudspeth Georgia Montouris LaDonna Marsh James L. Perhach R. Duane Sofia Timothy L. Macdonald 《Epilepsia》1999,40(6):769-776
PURPOSE: Previously we proposed and provided evidence for the metabolic pathway of felbamate (FBM), which leads to the reactive metabolite, 3-carbamoyl-2-phenylpropion-aldehyde. This aldehyde carbamate was suggested to be the reactive intermediate in the oxidation of 2-phenyl-1,3-propanediol monocarbamate to the major human metabolite 3-carbamoyl-2-phenylpropionic acid. In addition, the aldehyde carbamate was found to undergo spontaneous elimination to 2-phenylpropenal, commonly known as atropaldehyde. Moreover, atropaldehyde was proposed to play a role in the development of toxicity during FBM therapy. Evidence for atropaldehyde formation in vivo was reported with the identification of modified N-acetyl-cysteine conjugates of atropaldehyde in both human and rat urine after FBM administration. Identification of the atropaldehyde-derived mercapturic acids in urine after FBM administration is consistent with the hypothesis that atropaldehyde is formed in vivo and that it reacts with thiol nucleophiles. Based on the hypothesis that the potential for toxicity will correlate to the amount of atropaldehyde formed, we sought to develop an analytic method that would quantify the amount of relevant metabolites excreted in patient urine. METHODS: We summarize the results of an LC/MS method used to quantify FBM, 3-carbamoyl-2-phenylpropionic acid and two atropaldehyde-derived mercapturic acids in the patient population. RESULTS: Analysis was performed on 31 patients undergoing FBM therapy. The absolute quantities of FBM and three metabolites were measured. CONCLUSIONS: This method demonstrated sufficient precision for the identification of patients exhibiting "abnormal" levels of atropaldehyde conjugates and may hold potential for patient monitoring. 相似文献
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