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31.
Alp ?zgün B?rcek Soner ?ivi ?zgür ?cal ?zlem Gülbahar 《Journal of Korean Neurosurgical Society》2015,57(2):73-76
Objective
Tumor necrosis factor alpha (TNF-α) have proven effects in pathogenesis of neuroinflammation after spinal cord injury (SCI). Current study is designed to evaluate the effects of an anti-TNF-α agent, adalimumab, on spinal cord clip compression injury in rats.Methods
Thirty two male adult Wistar rats were divided into four groups (sham, trauma, infliximab, and adalimumab groups) and SCI was introduced using an aneurysm clip. Animals in treatment groups received 5 mg/kg subcutaneous adalimumab and infliximab right after the trauma. Malondialdehyde (MDA) levels were studied in traumatized spinal cord tissues 72 hours after the injury as a marker of lipid peroxidation.Results
Animals that received anti-TNF-α agents are found to have significantly decreased MDA levels. MDA levels were significantly different between the trauma and infliximab groups (p<0.01) and trauma and adalimumab groups (p=0.022). There was no significant difference in neurological evaluation of the rats using Tarlov scale.Conclusion
These results suggest that, like infliximab, adalimumab has favorable effects on lipid peroxidation induced by spinal cord trauma in rats. 相似文献32.
Alp Akonur Clifford J. Holmes John K. Leypoldt 《Peritoneal dialysis international》2015,35(3):288-296
♦ Background:
Contrary to ultrafiltration, the three-pore model predictions of icodextrin absorption from the peritoneal cavity have not yet been reported likely, in part, due to difficulties in estimating the degradation of glucose-polymer chains by α-amylase activity in dialysate. We incorporated this degradation process in a modified three-pore model of peritoneal transport to predict ultrafiltration and icodextrin absorption simultaneously in rats and humans.♦ Methods:
Separate three-pore models were constructed for humans and rats. The model for humans was adapted from PD Adequest 2.0 including a clearance term out of the peritoneal cavity to account for the absorption of large molecules to the peritoneal tissues, and considering patients who routinely used icodextrin by establishing steady-state plasma concentrations. The model for rats employed a standard three-pore model in which human kinetic parameters were scaled for a rat based on differences in body weight. Both models described the icodextrin molecular weight (MW) distribution as five distinct MW fractions. First order kinetics was applied using degradation rate constants obtained from previous in-vitro measurements using gel permeation chromatography. Ultrafiltration and absorption were predicted during a 4-hour exchange in rats, and 9 and 14-hour exchanges in humans with slow to fast transport characteristics with and without the effect of amylase activity.♦ Results:
In rats, the icodextrin MW profile shifted towards the low MW fractions due to complete disappearance of the MW fractions greater than 27.5 kDa. Including the effect of amylase activity (60 U/L) resulted in 21.1% increase in ultrafiltration (UF) (7.6 mL vs 6.0 mL) and 7.1% increase in icodextrin absorption (CHO) (62.5% with vs 58.1%). In humans, the shift in MW profile was less pronounced. The fast transport (H) patient absorbed more icodextrin than the slow transport (L) patient during both 14-hour (H: 47.9% vs L: 40.2%) and 9-hour (H: 37.4% vs L: 31.7%) exchanges. While the UF was higher during the longer exchange, it varied modestly among the patient types (14-hour range: 460 – 509 mL vs 9-hour range: 382 – 389 mL). When averaged over all patients, the increases in UF and CHO during the 14-hour exchange due to amylase activity (7 U/L) were 15% and 1.5%, respectively.♦ Conclusion:
The icodextrin absorption values predicted by the model agreed with those measured in rats and humans to accurately show the increased absorption in rats. Also, the model confirmed the previous suggestions by predicting an increase in UF specific to amylase activity in dialysate, likely due to the added osmolality by the small molecules generated as a result of the degradation process. As expected, this increase was more pronounced in rats than in humans because of higher dialysate concentrations of amylase in rats. 相似文献33.
Christopher A. Rice Beatrice L. Colon Mehmet Alp Hakan G?ker David W. Boykin Dennis E. Kyle 《Antimicrobial agents and chemotherapy》2015,59(4):2037-2044
Naegleria fowleri is a pathogenic free-living amoeba (FLA) that causes an acute fatal disease known as primary amoebic meningoencephalitis (PAM). The major problem for infections with any pathogenic FLA is a lack of effective therapeutics, since PAM has a case mortality rate approaching 99%. Clearly, new drugs that are potent and have rapid onset of action are needed to enhance the treatment regimens for PAM. Diamidines have demonstrated potency against multiple pathogens, including FLA, and are known to cross the blood-brain barrier to cure other protozoan diseases of the central nervous system. Therefore, amidino derivatives serve as an important chemotype for discovery of new drugs. In this study, we validated two new in vitro assays suitable for medium- or high-throughput drug discovery and used these for N. fowleri. We next screened over 150 amidino derivatives of multiple structural classes and identified two hit series with nM potency that are suitable for further lead optimization as new drugs for this neglected disease. These include both mono- and diamidino derivatives, with the most potent compound (DB173) having a 50% inhibitory concentration (IC50) of 177 nM. Similarly, we identified 10 additional analogues with IC50s of <1 μM, with many of these having reasonable selectivity indices. The most potent hits were >500 times more potent than pentamidine. In summary, the mono- and diamidino derivatives offer potential for lead optimization to develop new drugs to treat central nervous system infections with N. fowleri. 相似文献
34.
35.
Meric A. Altinoz Aysel Ozpinar Alp Ozpinar Emily Hacker lhan Elmaci 《Clinical and experimental pharmacology & physiology》2019,46(8):694-704
In this review article, we hypothesize that Hepatitis B Virus Vaccine (HBV‐V) and certain antigens of Hepatitis B Virus (HBV) could act as anticancer immunoadjuvants in addition to their role of preventing HBV‐associated liver cancer. Evidence suggests that in animal breast cancer and melanoma models, combining hepatitis B‐surface antigen (HBsAg) with other cancer antigens resulted in enhanced antitumour activity. HBsAg shares antigenic mimicry with healthy and malignant cells including squamous epithelia, thymic epithelia, bladder‐ and colon cancer cells. There exist anecdotal reports and small case series about spontaneous remission of leukaemias and neuroblastoma following acute HBV‐infection. Recent studies also exist showing HBV‐carrier state is a good prognostic factor for intrahepatic cholangiocarcinoma. Further epidemiological studies and animal experiments are necessary whether HBV‐Vs exert additional immunoadjuvant benefits besides lowering the risk of liver cancer. 相似文献
36.
37.
Galinato MG Kleingardner JG Bowman SE Alp EE Zhao J Bren KL Lehnert N 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(23):8896-8900
The active site of cytochrome c (Cyt c) consists of a heme covalently linked to a pentapeptide segment (Cys-X-X-Cys-His), which provides a link between the heme and the protein surface, where the redox partners of Cyt c bind. To elucidate the vibrational properties of heme c, nuclear resonance vibrational spectroscopy (NRVS) measurements were performed on (57)Fe-labeled ferric Hydrogenobacter thermophilus cytochrome c(552), including (13)C(8)-heme-, (13)C(5)(15)N-Met-, and (13)C(15)N-polypeptide (pp)-labeled samples, revealing heme-based vibrational modes in the 200- to 450-cm(-1) spectral region. Simulations of the NRVS spectra of H. thermophilus cytochrome c(552) allowed for a complete assignment of the Fe vibrational spectrum of the protein-bound heme, as well as the quantitative determination of the amount of mixing between local heme vibrations and pp modes from the Cys-X-X-Cys-His motif. These results provide the basis to propose that heme-pp vibrational dynamic couplings play a role in electron transfer (ET) by coupling vibrations of the heme directly to vibrations of the pp at the protein-protein interface. This could allow for the direct transduction of the thermal (vibrational) energy from the protein surface to the heme that is released on protein/protein complex formation, or it could modulate the heme vibrations in the protein/protein complex to minimize reorganization energy. Both mechanisms lower energy barriers for ET. Notably, the conformation of the distal Met side chain is fine-tuned in the protein to localize heme-pp mixed vibrations within the 250- to 400-cm(-1) spectral region. These findings point to a particular orientation of the distal Met that maximizes ET. 相似文献
38.
Ahmet Bacaksiz Mehmet Akif Vatankulu Mehmet Kayrak Hasan Huseyin Telli Selim S. Ayhan Osman Sonmez Ayse Alp Sadik Buyukbas 《Clinics (S?o Paulo, Brazil)》2013,68(7):997-1003
OBJECTIVES:
Acute ST-elevation myocardial infarction is associated with ventricular dysfunction due to ischemia-induced progressive myocardial damage. The decrease in ventricular compliance causes left atrial dilatation and stretching of the atrial myocardium, which are the main stimuli for the secretion of atrial natriuretic peptide. The aim of this study was to evaluate left atrial dimensions and atrial natriuretic peptide levels in patients early after their first acute ST-elevation myocardial infarction and assess the probable interaction between coronary lesions and these measurements.METHODS:
A total of 110 patients with acute myocardial infarction and 50 controls were studied. Plasma atrial natriuretic peptide was measured at admission. Left ventricular function, diameter, and volume index were evaluated using transthoracic echocardiography. Gensini and vessel scores of the patients who underwent coronary angiography were calculated.RESULTS:
Plasma atrial natriuretic peptide in the patients with myocardial infarction was increased compared with that in controls (3.90±3.75 vs. 1.35±0.72 nmol/L, p<0.001). Although the left atrial diameter was comparable in patients and controls, the left atrial volume index was increased in patients with acute myocardial infarction (26.5±7.1 vs. 21.3±4.9 mL/m2, p<0.01). Multivariate regression analysis showed a strong independent correlation between the left atrial volume index and the plasma atrial natriuretic peptide level (β = 0.23, p = 0.03).CONCLUSIONS:
The left atrial volume index and plasma atrial natriuretic peptide level were correlated in patients with acute myocardial infarction. 相似文献39.
40.
S. Romero-Vargas B. Zárate-Kalfópulos E. Otero-Cámara L. Rosales-Olivarez A. Alpízar-Aguirre Eugenio Morales-Hernández Alejandro Reyes-Sánchez 《European spine journal》2013,22(4):878-882