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61.
Alcón VL Foldvari M Snider M Willson P Gomis S Hecker R Babiuk LA Baca-Estrada ME 《Vaccine》2003,21(17-18):1811-1814
A large number of studies demonstrated the immunostimulatory effects of CpG oligonucleotides (ODN), particularly in mice. In the present study, we evaluated the ability of lipid-based delivery systems to enhance the adjuvant effect of CpG-ODN and protect against infection in a porcine pleuropneumonia model. Increased levels of OmlA-specific antibody were detected in animals immunised with OmlA and CpG-ODN formulated in the delivery system Biphasix-vaccine targeting adjuvant (VTA), compared to pigs immunised with VTA without CpG-ODN or CpG-ODN alone. In addition, the responses induced by VTA/CpG formulation were similar to those induced by the commercial adjuvant VSA; however, VTA formulations caused significantly less tissue damage than VSA. 相似文献
62.
63.
Pharmacokinetic properties of single-dose loratadine and ambroxol alone and combined in tablet formulations in healthy men 总被引:2,自引:0,他引:2
Villacampa J Alcántar F Rodríguez JM Morales JM Herrera J Rosete R 《Clinical therapeutics》2003,25(8):2225-2232
BACKGROUND: Due to Mexico's complicated socioeconomic environment, causing a high occurrence of >1 person sharing a single room, respiratory conditions are spread easily. Respiratory conditions are the main reason for consultation with a physician. The most frequent symptoms are throat soreness and cough; therefore, a new formulation combining loratadine and ambroxol hydrochloride was designed to treat these 2 major symptoms. The combination is expected to provide relief when coprescribed with more specific therapies, such as antibiotics. OBJECTIVE: This study determined the pharmacokinetic profile of single-dose loratadine-ambroxol hydrochloride combination therapy versus each component given separately. The analyses included descarboethoxyloratadine (DCL), the primary active metabolite of loratadine. METHODS: This was a 4-week, single-center, randomized, open-label, 3-period crossover study in adult male volunteers aged 18 to 50 years and in good general health. Subjects were randomized to receive single doses of treatment A (2 loratadine 5-mg tablets + ambroxol 30-mg tablets), B (2 ambroxol 30-mg tablets), or C (1 loratadine 10-mg tablet) in 1 of 3 sequences (ABC, BCA, or CAB) per period. A 14-day washout period separated each treatment period. Plasma concentration-time data curves for each subject and treatment were analyzed by noncompart-mental methods to obtain values for area under the curve (AUC), maximum plasma concentration (C(max)), and time to reach C(max) (T(max)). RESULTS: Thirty subjects (mean [SD] age, 22.5 [2.6] years) were enrolled. All treatments were well tolerated. Formulations A and C produced similar loratadine and DCL AUC from time 0 to 24 hours (AUC(0-24)) values, but showed slightly high C(max). values for loratadine and slightly low C(max) values for DCL, indicating failure to demonstrate bioinequivalence. Formulations A and B produced similar ambroxol C(max), T(max), and AUC(0-24) values. CONCLUSIONS: In this population of healthy mate volunteers, results showed the bioavailability of loratadine and ambroxol from the new formulation and did not show impairment of absorption when the drugs were formulated in a combination tablet. 相似文献
64.
Moore BC Glasberg BR Alcántara JI Launer S Kuehnel V 《British journal of audiology》2001,35(6):365-374
The inherent amplitude fluctuations in narrow bands of noise may limit the ability to detect gaps in the noise; 'dips' in the noise may be confused with the gap to be detected. For people with cochlear hearing loss, loudness recruitment may effectively magnify the fluctuations and this could partly account for the reduced ability to detect gaps in noise bands that is usually found for such people. Previously, we tested these ideas by processing the envelopes of noise bands to alter the amount of envelope fluctuation. We showed that instantaneous compression, implemented via processing of the Hilbert envelope, led to smaller (that is, better) gap detection thresholds for subjects with cochlear hearing loss. In the present experiment, we determined whether fast-acting compression of the type sometimes used in hearing aids could also lead to improved gap detection. A behind-the-ear (BTE) digital hearing aid was programmed to implement multi-band compression, either fast-acting or slow-acting (control condition). A reference condition using unaided listening was also used. Stimuli were delivered via an earphone placed over the hearing aid. Overall stimulus levels at the output of the hearing aid were similar across conditions. Thresholds for detecting gaps in noise bands centred at 4 kHz were measured as a function of noise bandwidth (10-500 Hz). To prevent the detection of spectral changes introduced by the gap, stimuli were presented in a broad-band background noise. Three normally hearing subjects and three subjects with bilateral cochlear hearing loss were tested. Gap thresholds varied non-monotonically with noise bandwidth, being maximal around 50 Hz. Gap thresholds were generally higher for the hearing-impaired than for the normally hearing subjects. For the latter, gap thresholds were similar for the three conditions. For the hearing-impaired subjects, gap thresholds were similar for the unaided condition and the condition using slow compression. However, fast compression led to smaller gap thresholds, especially for noise bandwidths up to 50 Hz. The results show that fast compression can improve the ability of hearing-impaired subjects to detect gaps in sounds with slowly fluctuating envelopes. 相似文献
65.
66.
Alcántara-Hernández R Leyva-Illades D García-Sáinz JA 《European journal of pharmacology》2001,419(1):9-13
alpha(1b)-Adrenoceptors immunoprecipitated with protein kinase C alpha, delta, and epsilon isoforms under basal conditions and such coimmunoprecipitations were increased in cells treated with phorbol myristate acetate. The increased coimmunoprecipitations induced by phorbol myristate acetate were concentration-dependent and reached their maxima 1 to 2 min after the addition of the tumor promoter. No coimmunoprecipitation of protein kinase C zeta and alpha(1b)-adrenoceptors was detected. Norepinephrine, endothelin-1, lysophosphatidic acid and epidermal growth factor were also able to increase the coimmunoprecipitation of protein kinase C isoenzymes and alpha(1b)-adrenoceptors. These data support the idea that protein kinase-receptor complexes might form and could be relevant in receptor desensitization. 相似文献
67.
Eleazar Soto Jimmy Espinoza Jyh Kae Nien Juan Pedro Kusanovic Offer Erez Karina Richani Joaquin Santolaya-Forgas Roberto Romero 《The journal of maternal-fetal & neonatal medicine》2007,20(1):15-22
OBJECTIVE: Human beta-defensin-2 (HBD-2) is a potent antimicrobial peptide that is part of the innate immune response. The purpose of this study was to determine whether HBD-2 is present in amniotic fluid and if its concentration changes with microbial invasion of the amniotic cavity (MIAC) and labor. STUDY DESIGN: Amniotic fluid was retrieved by amniocentesis from 318 patients in the following groups: (1) mid-trimester (n=75); (2) term not in labor (n=28) and in labor (n=51); (3) preterm labor and intact membranes without MIAC who delivered at term (n=36), who delivered preterm without MIAC (n=52), and preterm labor with MIAC who delivered preterm (n=25); and (4) preterm premature rupture of membranes (preterm PROM) with (n=25) and without MIAC (n=26). MIAC was defined as a positive amniotic fluid culture for microorganisms. Amniotic fluid HBD-2 concentrations were determined using a sensitive and specific ELISA. Non-parametric statistics were used for analysis. RESULTS: (1) HBD-2 was detected in all amniotic fluid samples; (2) the concentration of HBD-2 did not change with gestational age from mid-trimester to term (p=0.8); (3) intra-amniotic infection was associated with a significant increase in amniotic fluid concentrations of HBD-2 in both women with preterm labor and intact membranes, and women with preterm PROM (p<0.05 for each comparison); (4) patients with preterm labor and a negative amniotic fluid culture who delivered preterm had a higher median amniotic fluid HBD-2 concentration than those with preterm labor who delivered at term (p=0.001); and (5) among patients with preterm labor without MIAC, those who had intra-amniotic inflammation (amniotic fluid white blood cell count>100 cells per mL) had a higher median amniotic fluid concentration of HBD-2 than those without this condition (p<0.002). CONCLUSION: (1) Amniotic fluid contains HBD-2, a natural antimicrobial peptide, and this may account for some of the antimicrobial activity of amniotic fluid; (2) amniotic fluid HBD-2 concentrations are increased in women with MIAC, regardless of the membrane status (intact membranes or PROM); and (3) we propose that amniotic fluid HBD-2 is part of the innate immune system within the amniotic cavity. 相似文献
68.
Alcántara-Hernández R Vázquez-Prado J Gárcia-Sáinz JA 《British journal of pharmacology》2000,129(4):724-730
In the present work we studied the effect of protein phosphatase inhibitors on the phosphorylation state and function of alpha(1b)-adrenoceptors. Okadaic acid increased receptor phosphorylation in a time- and concentration-dependent fashion (maximum at 30 min, EC(50) of 30 nM). Other inhibitors of protein phosphatases (calyculin A, tautomycin and cypermethrin) mimicked this effect. Staurosporine and Ro 31-8220, inhibitors of protein kinase C, blocked the effect of okadaic acid on receptor phosphorylation. Neither genistein nor wortmannin altered the effect of okadaic acid. The intense adrenoceptor phosphorylation induced by okadaic acid altered the adrenoceptor-G protein coupling, as evidenced by a small decreased noradrenaline-stimulated [(35)S]GTPgammaS binding. Okadaic acid did not alter the noradrenaline-stimulated increases in intracellular calcium or the production of inositol trisphosphate. Our data indicate that inhibition of protein phosphatases increases the phosphorylation state of alpha(1b)-adrenoceptors; this effect seems to involve protein kinase C. In spite of inducing an intense receptor phosphorylation, okadaic acid alters alpha(1b)-adrenergic actions to a much lesser extent than the direct activation of protein kinase C by phorbol myristate acetate. 相似文献
69.
Marcos Almeida Matos Luiz Antonio Alcântara de Oliveira 《The Journal of foot and ankle surgery》2010,49(4):395-397
The objective of our study was to compare both Kite's and Ponseti's methods to evidence which one is the most efficient technique in the treatment of congenital idiopathic clubfoot, based on a meta-analysis of current scientific literature. We performed a search of the past 20 years of literature (1986 to 2006) on MEDLINE, LILACS, and EMBASE databases for clinical trials that compared both Kite's and Ponseti's methods. The search in the literature provided 4 selected papers for the meta-analysis. There was a significant difference between the groups, in which the Ponseti's group was more effective in treating congenital clubfoot, considering both primary correction (P = .001) and uncorrected plus relapsed feet (P = .014). In conclusion, our meta-analysis indicates that Ponseti's group in the clubfoot treatment was superior to Kite's group; however, the available studies have some methodological limitations such as small sample sizes and historical control. 相似文献
70.
Janaína de Albuquerque Couto Karina Lidianne Alcântara Saraiva Cleiton Diniz Barros Daniel Pedro Udrisar Christina Alves Peixoto Juliany Silveira Braglia César Vieira Maria do Carmo Alves de Lima Suely Lins Galdino Ivan da Rocha Pitta Maria Inês Wanderley 《Medicinal chemistry research》2013,22(1):240-246
Thiazolidinediones work by sensitizing the action of insulin by acting as ligands for the PPAR receptor. This study describes the effects of chronic treatment with new benzylidene-thiazolidine-2,4-dione (LPSF/GQ-06) on Leydig cell steroidogenic capacity, and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal rats. Twelve adult male Wistar rats were treated with LPSF/GQ-06 (5 mg/kg) administered by gavage for 15 days. Testosterone in plasma and incubation medium was measured by radioimmunoassay. The StAR and P450scc expression was detected by immunocytochemistry. The levels of total circulating testosterone were increased by LPSF/GQ-06 treatment. The ability of LPSF/GQ-06 to affect the production of testosterone by Leydig cells was examined using an ex vivo model. The production of testosterone was induced by activators of the cAMP/PKA pathway (hCG and dbcAMP) or substrates of steroidogenesis (22(R)-hydroxycholesterol, substrate for the P450scc enzyme, and pregnenolone, the product of the P450scc-catalyzed step). An increase in basal or induced testosterone production was observed in Leydig cells from LPSF/GQ-06-treated rats. The ultrastructural and immunocytochemical analysis showed that LPSF/GQ-06-treated Leydig cells presented morphological characteristics similar to those of control cells as well as similar labeling to StAR and P450scc throughout the cytoplasm of control and treated cells. We can therefore conclude that the stimulatory action of the LPSF/GQ-06 on testosterone production is not due to an increase of the quantity of StAR or P450scc. These results suggest that the activity of these two proteins as well as of other steroidogenic enzymes is augmented by LPSF/GQ-06. 相似文献