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941.
942.
Izabela E. Fedyszyn Jo Robinson Thomas Matyas Meredith G. Harris Susan J. Paxton 《Psychiatry research》2010,175(1-2):98-103
Individuals with a first episode of psychotic illness are known to be at high risk of suicide, yet little is understood about the timing of risk in this critical period. The present study aimed to examine the temporal pattern of suicide risk in patients with early psychosis (EP) and to determine whether discrete periods of significantly elevated risk can be identified up to 24 months after commencing treatment. Suicidality ratings collected each month as part of patient routine assessment at the Early Psychosis Prevention and Intervention Centre (EPPIC) were retrieved from the service database for patients treated between December 2002 and December 2005 (N = 696). Time-series analysis was performed on suicide risk estimated from the aggregated data of 94 individuals who met the study inclusion criteria. Suicide risk was highest in the first month of treatment, decreasing rapidly over the next 6 months and declining slightly thereafter. A power function adequately described this curvilinear trend. Fluctuations around the trend were unpredictable, except for a mild tendency to reverse from month to month, and did not reach statistical significance. The findings suggest limited scope for preventative interventions driven by chronology alone. Intensive routine suicide screening across the course of treatment may facilitate identification and early management of EP patients at suicide risk. 相似文献
943.
944.
Kocić I Ruczyński J Szczepańska R Olkowicz M Parfianowicz B Rusiecka I Rekowski P 《Pharmacological reports : PR》2011,63(1):195-199
Cell-penetrating peptides (CPP) are a family of peptides able to penetrate the cell membrane. This group of compounds has attracted consideration as potential therapeutic tools for the delivery of various substances into cells. Here, we investigated possible interactions between several CPP synthesized in our laboratory and the vascular action of phenylephrine. We used isolated rat tail artery and examined the influence of pretreatment by seven different CPP on the concentration-response curve induced by the α1 receptor agonist phenylephrine. Peptides were synthesized by solid-phase peptide synthesis (SPPS) using the 9-fluorenylmethoxycarbonyl (Fmoc) method. Among the seven different polypeptides, i.e., TP10 (transportan-10), [Lys(AAc)13]TP, [Lys(CAc)13]TP, [Lys(GAc)13]TP, [Lys(TAc)13]TP, [Lys(UAc)13]TP and [Lys(Ac)13]TP, only TP10 and [Lys(AAc)13]TP, both at a concentration of 1 μM (the lowest concentration inducing a significant change in the contraction of isolated rat stomach in our pilot study), rendered rat tail artery more sensitive to phenylephrine; the relative potency increased significantly. Conversely, [Lys(Ac)13]TP strongly decreased the efficacy of phenylephrine. 相似文献
945.
Izabela Janiec Bozena Werner Jolanta Sieminska Ulrike Ravens-Sieberer 《Quality of life research》2011,20(4):537-541
Objective
The aim of our prospective study was to assess the health-related quality of life (HRQOL) of children with mitral valve prolapse (MVP) and the impact of clinical symptoms on HRQOL. 相似文献946.
Kunal Bhattacharya Pratap C. Naha Izabela Naydenova Svetlana Mintova Hugh J. Byrne 《Toxicology letters》2012
Increasing utilization of engineered nanoparticles in the field of electronics and biomedical applications demands an assessment of risk associated with deliberate or accidental exposure. Metal based nanoparticles are potentially most important of all the nanoparticles in terms of health risks. Microporous alumino-silicates and pure silicates named as zeolites and zeo-type materials with variety of structures, chemical compositions, particle sizes and morphologies have a significant number of industrial uses such as in catalysis, sorption and ion-exchange processes. In particular, the nanosized particles due to their unique properties are used in hybrid organic-inorganic materials for photography, photonics, electronics, labeling, imaging, and sensing. The aim of the current study is to investigate pure silica MFI-type zeolites nanoparticles with sizes of 50 nm and 100 nm (samples MFI-50 and MFI-100) under suspended conditions and their toxicological effects on human lung alveolar (A549) cells under in vitro conditions. 相似文献
947.
Gutowska I Baranowska-Bosiacka I Noceń I Piotrowska K Marchlewicz M Wiernicki I Chlubek D Wiszniewska B 《Human & experimental toxicology》2012,31(4):346-354
The aim of this study was to assess the influence of soy isoflavones, administered pre- and later postnatally, on the estrogen receptor α (ERα) and β (ERβ) expression in bones and to examine the mineral metabolism of the skeletal system in male rats. In bones, ERs were examined with an immunohistochemical method; in blood, estradiol with chemiluminescence immunoassay and in blood and bones, calcium and magnesium with atomic absorption spectrometry and fluorides with a potentiometric method were examined. Decreased immunoexpression of ERα and the increased intensity of immunofluorescence of ERβ in osteocytes in the femur of experimental rats were observed. In the serum of treated rats, a significantly higher concentration of estradiol and lower calcium were observed. The content of magnesium and fluoride were significantly higher in the bones of the examined animals. The data presented show that pre- and postnatal supplementation of male rats with soy isoflavones may considerably increase the concentration of estrogens in serum, with a concurrent effect on the mineral composition of bones. 相似文献
948.
Elżbieta Jakubowska-Pietkiewicz Wojciech Fendler Wojciech Młynarski Izabela Klich Danuta Chlebna-Sokół 《Central European Journal of Medicine》2012,7(5):635-641
Bone fractures may depend on Vitamin D Receptor Gene (VDR), bone mineral density, bone turnover markers. Patients and methods. 161 patients were recruited and underwent: skeletal
densitometry (DXA) method and bone turnover studies (Osteocalcin and Ntx).The study group was evaluated using restriction
enzyme digestion at BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232) and TaqI (rs731236), polymorphic sites of the VDR gene. Multivariate logistic regression was used to assess factor significance. The
model included variables with sex- and age-standardized parameters, VDR genotypes, and bone metabolism marker levels. Results.
Factors associated with fractures were: osteocalcin concentration and Z-score BMDt. Odds Ratio (OR) values equaled: 1.01 (95%Confidence
Interval (95%CI) 1.00–1.02) for osteocalcin (p=0.006), and 0.66 (95%CI 0.42-1.03; p=0.07) for Z-score BMDt. In patients with
reduced bone mass, factors related to fractures were: osteocalcin (0.04) and carriage of BsmI b (0.07) or ApaI a alleles (0.08). ORs were 1.01 (95%CI 1.00–1.02) for OC, 0.29 (95%CI 0.07–1.14) for BsmI, and 2.13 (95%CI 0.91–4.99) for ApaI polymorphic allele carriage. Conclusions. Carriage of BsmI b allele reduces, while carriage of ApaI a allele and heightened osteoclacin level increase the risk of fractures in study children with reduced bone mass. VDR polymorphism,
bone mineral density and bone formation’s marker — osteocalcin maybe considered as risk factor for fracure in children from
Lodz region. 相似文献
949.
2D-TLC and RP-HPLC methods were applied to qualitatively determinate free phenolic acids and those liberated by acid and alkaline hydrolysis in the flowers and leaves of G. robusta and G. squarrosa. The presence of eleven phenolic acids, namely: caffeic, chlorogenic, p-coumaric, p-hydroxybenzoic, ferulic, gallic, protocatechuic, vanillic salicylic, p-hydroxyphenylacetic and ellagic acids was determined. Quantitative estimate of phenolic acids, expressed as caffeic acid, has been analyzed by the method described in the Polish Pharmacopoeia VIII. The content of phenolic acids in G. robusta reached 7.33 mg/g and 6.23 mg/g for flowers and leaves, respectively. The flowers and leaves of G. squarrosa were characterized by similar level of phenolic acids, namely 6.81 mg/g and 6.59 mg/g, respectively. 相似文献
950.
Since a few years, attempts are taken at the application of vagus nerve stimulation in the treatment of severe depression. It appears that the vagus nerve exerts a direct influence on areas of the brain associated with the regulation of mood and increases the level of biogenic amines. What is more, studies have confirmed an increased activity of fronto-orbital and prefrontal cortex, hypothalamus, cingulum and an increased concentration of serotonin and noradrenalin in the CNS and in the cerebro-spinal fluid. Preliminary clinical trials have confirmed the efficacy, good tolerance and safety of this treatment modality, although some objections have been raised whether these promising results were not partly due to the placebo effect. Therefore new, multicenter clinical studies have been designed, enabling an unbiased evaluation of usefulness of this method in the treatment of depression. 相似文献