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排序方式: 共有230条查询结果,搜索用时 15 毫秒
1.
This study invokes the ecological approach to social support by examining how school social support relates to moderate or severe adolescent depression. School is seen as not only a place for supportive individual‐level relationships, but also as a source of community support created by teachers and other students. The main purpose of the study is to examine whether school‐level social support is related to adolescent depression and, if so, how much of the school‐level differences in moderate or severe adolescent depression can be explained by school social support? The study is based on data included in the Finnish School Health Promotion Survey, which covers about 70% of Finnish 14‐ to 16‐year‐old adolescents. The data were collected in 2002–2003 and the analysis was conducted by employing multilevel logistic regression analysis. © 2008 Wiley Periodicals, Inc. 相似文献
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Saroj Neupane M.D. Naga VA Kommuri M.D. Noora Kazanji D.O. Pertha Chowdhury M.D. F.A.C.C. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(11):1788-1789
Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging. 相似文献
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Ungureanu D Vanhatupa S Kotaja N Yang J Aittomaki S Jänne OA Palvimo JJ Silvennoinen O 《Blood》2003,102(9):3311-3313
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Virtanen I Korhonen M Petäjäniemi N Karhunen T Thornell LE Sorokin LM Konttinen YT 《The Journal of clinical endocrinology and metabolism》2003,88(10):4960-4966
Laminin has been proposed to influence the function of human adrenal cortex. We have studied the distribution of laminin (Ln) chains using immunofluorescence in human fetal and adult adrenal cortex. In the fetal gland Ln alpha2- and alpha5-chains were weakly expressed in the definitive zone, whereas Ln alpha4-, beta1-, and gamma1-chains occurred around vessels. In the adult gland, Ln alpha2-, alpha5-, and gamma1-chains were found in epithelial basement membranes (BM) in all cortical zones, Ln alpha4-chain in vessels, Ln beta1-chain in outer zone, and Ln beta2-chain in the two inner zones of the cortex, respectively. Among the integrins in adult gland, integrin alpha(3)-subunit was confined to basal surfaces of cortical cells, alpha(6) to vessels, alpha(1) to the stroma, and alpha(2) diffusely to epithelial cells. Lutheran glycoprotein and dystroglycan occurred in the fetal gland diffusely in the definitive zone and throughout the epithelium in the adult. The isoform composition of BM of the adult adrenal gland is distinct, with Ln-2 and -10 in BM of the outer zone and Ln-4 and -11 in BM of the two inner zones. The results suggest that integrin alpha(3)beta(1) and Lutheran are candidate receptors for Ln-10 and -11, whereas dystroglycan probably binds Ln-2 and -4. 相似文献
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Lisa Mosconi Juha O. Rinne Wai H. Tsui John Murray Yi Li Lidia Glodzik Pauline McHugh Schantel Williams Megan Cummings Elizabeth Pirraglia Stanley J. Goldsmith Shankar Vallabhajosula Noora Scheinin Tapio Viljanen Kjell Någren Mony J. de Leon 《Neurobiology of aging》2013
This study examines the relationship between fibrillar beta-amyloid (Aβ) deposition and reduced glucose metabolism, a proxy for neuronal dysfunction, in cognitively normal (NL) individuals with a parent affected by late-onset Alzheimer's disease (AD). Forty-seven 40–80-year-old NL received positron emission tomography (PET) with 11C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated in posterior cingulate, frontal, and parieto-temporal regions (Pearson r ≤ −0.57, p ≤ 0.05). No correlations were observed in NH and PH. The combination of Aβ deposition and metabolism yielded accuracy ≥ 69% for MH vs. NH and ≥ 71% for MH vs. PH, with relative risk = 1.9–5.1 (p values < 0.005). NL individuals with AD-affected mothers show co-occurring Aβ increases and hypometabolism in AD-vulnerable regions, suggesting an increased risk for AD. 相似文献
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Hemalatha Parangusan Jolly Bhadra Zubair Ahmad Shoaib Mallick Farid Touati Noora Al-Thani 《RSC advances》2020,10(45):26604
Polyaniline (PANI)/Cu–ZnS composites with porous microspheres are prepared by a hydrothermal and in situ polymerization method. The structural, optical, and morphological properties are characterized by X-ray powder diffraction, FTIR, UV-vis, scanning electron microscope, transmission electron microscope. The XRD results confirmed that the PANI/Cu–ZnS composite is formed. The morphological analyses exhibited that the PANI/Cu–ZnS composite comprises the porous microspherical structures. The emission peaks obtained in photoluminescence spectra confirm the presence of surface defects in the prepared composite. The UV-DRS study shows that the bandgap of the samples is found to decrease for the PANI/Cu–ZnS composite compared to the pure Cu–ZnS sample. The calculated band gap (Eg) value of PANI/Cu–ZnS composite is 2.47 eV. Furthermore, the fabricated gas sensor based on PANI/Cu–ZnS can perform at room temperature and exhibits good gas sensing performance toward CO2 gas. In particular, PANI/Cu–ZnS sensor shows good response (31 s) and recovery time (23 s) upon exposure to CO2 gas. The p/n heterojunction, surface defects, and porous nature of the PANI/Cu–ZnS composite microsphere enhanced sensor performance.Polyaniline (PANI)/Cu–ZnS composites with porous microspheres are prepared by a hydrothermal and in situ polymerization method. 相似文献
9.
John S. Millar Gissette Reyes-Soffer Patricia Jumes Richard L. Dunbar Emil M. deGoma Amanda L. Baer Wahida Karmally Daniel S. Donovan Hashmi Rafeek Laura Pollan Junichiro Tohyama Amy O. Johnson-Levonas John A. Wagner Stephen Holleran Joseph Obunike Yang Liu Rajasekhar Ramakrishnan Michael E. Lassman David E. Gutstein Henry N. Ginsberg Daniel J. Rader 《The Journal of clinical investigation》2015,125(6):2510-2522
BACKGROUND. Individuals treated with the cholesteryl ester transfer protein (CETP) inhibitor anacetrapib exhibit a reduction in both LDL cholesterol and apolipoprotein B (ApoB) in response to monotherapy or combination therapy with a statin. It is not clear how anacetrapib exerts these effects; therefore, the goal of this study was to determine the kinetic mechanism responsible for the reduction in LDL and ApoB in response to anacetrapib.METHODS. We performed a trial of the effects of anacetrapib on ApoB kinetics. Mildly hypercholesterolemic subjects were randomized to background treatment of either placebo (n = 10) or 20 mg atorvastatin (ATV) (n = 29) for 4 weeks. All subjects then added 100 mg anacetrapib to background treatment for 8 weeks. Following each study period, subjects underwent a metabolic study to determine the LDL-ApoB-100 and proprotein convertase subtilisin/kexin type 9 (PCSK9) production rate (PR) and fractional catabolic rate (FCR).RESULTS. Anacetrapib markedly reduced the LDL-ApoB-100 pool size (PS) in both the placebo and ATV groups. These changes in PS resulted from substantial increases in LDL-ApoB-100 FCRs in both groups. Anacetrapib had no effect on LDL-ApoB-100 PRs in either treatment group. Moreover, there were no changes in the PCSK9 PS, FCR, or PR in either group. Anacetrapib treatment was associated with considerable increases in the LDL triglyceride/cholesterol ratio and LDL size by NMR.CONCLUSION. These data indicate that anacetrapib, given alone or in combination with a statin, reduces LDL-ApoB-100 levels by increasing the rate of ApoB-100 fractional clearance.TRIAL REGISTRATION. ClinicalTrials.gov .FUNDING. Merck & Co. Inc., Kenilworth, New Jersey, USA. Additional support for instrumentation was obtained from the National Center for Advancing Translational Sciences (UL1TR000003 and UL1TR000040). NCT00990808相似文献
10.
Kemppainen H Raivio N Suo-Yrjo V Kiianmaa K 《Alcoholism, clinical and experimental research》2012,36(2):286-293
Background: Striatopallidal medium spiny neurons have been viewed as a final common path for drug reward and the ventral pallidum as an essential convergent point for hedonic and motivational signaling in the brain. The medium spiny neurons are GABAergic, but they colocalize enkephalin. Purpose of this study was to investigate the role of the opioidergic mechanisms of the ventral pallidum in ethanol self‐administration behavior. Methods: Effects of bilateral microinjections of μ‐, δ‐, and κ‐opioid receptor agonists and antagonists into the ventral pallidum on voluntary ethanol consumption were monitored in alcohol‐preferring Alko Alcohol (AA) rats using the 90‐minute limited access paradigm. Results: Stimulation of μ‐opioid receptors with DAMGO (0.01 to 0.1 μg) or morphine (1 to 10 μg) in the ventral pallidum decreased ethanol intake dose‐dependently. Conversely, blocking μ‐receptors with CTOP (0.3 to 3 μg) increased ethanol intake significantly. Unlike CTOP, DAMGO also increased locomotor activity. Consumption of ethanol was not modified significantly by a broad‐spectrum opioid receptor antagonist naltrexone, by δ‐opioid receptor agonist DPDPE or antagonist naltrindole, or by a κ‐opioid receptor agonist U50,488H or antagonist nor‐BNI. Conclusions: The study provides evidence for μ‐ but not δ‐ or κ‐opioid receptors in the ventral pallidum playing a role in the regulation of voluntary ethanol consumption. Furthermore, present findings give support to earlier work, suggesting an essential role of pallidal opioidergic transmission in drug reward. 相似文献