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Jenny Brjesson Axn Rudi Soares Oskar Wallmark Peter Thelin Erika Widenkvist Zetterstrm Gran Lindbergh 《Materials》2021,14(5)
Batteries in energy storage systems are exposed to electrical noise, such as alternating current (AC) harmonics. While there have been many studies investigating whether Lithium-ion batteries are affected by AC harmonics, such studies on Nickel Metal Hydride (NiMH) batteries are scarce. In this study a 10 Ah, 12 V NiMH battery was tested with three different harmonic current frequency overlays during a single charge/discharge cycle: 50 Hz, 100 Hz, and 1000 Hz. No effect on battery internal temperature or gas pressure was found, indicating that NiMH battery aging is not affected by the tested harmonic AC frequencies. This can reduce the cost of energy storage systems, as no extra filters are needed to safeguard the batteries. Instead, the capacitive properties of the batteries give the possibility to use the battery bank itself as a high pass filter, further reducing system complexity and cost. 相似文献
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Manuelle Medizin - Die Indikation zum prothetischen Ersatz der oberen Extremität wurde in den letzten Jahren von der klassischen Amputation auch auf Patienten mit Verlust oder angeborenen... 相似文献
44.
Osteopontin expression in human and murine obesity: extensive local up-regulation in adipose tissue but minimal systemic alterations 总被引:1,自引:0,他引:1
Kiefer FW Zeyda M Todoric J Huber J Geyeregger R Weichhart T Aszmann O Ludvik B Silberhumer GR Prager G Stulnig TM 《Endocrinology》2008,149(3):1350-1357
Obesity is associated with a chronic low-grade inflammation characterized by macrophage infiltration of adipose tissue (AT) that may underlie the development of insulin resistance and type 2 diabetes. Osteopontin (OPN) is a multifunctional protein involved in various inflammatory processes, cell migration, and tissue remodeling. Because these processes occur in the AT of obese patients, we studied in detail the regulation of OPN expression in human and murine obesity. The study included 20 morbidly obese patients and 20 age- and sex-matched control subjects, as well as two models (diet-induced and genetic) of murine obesity. In high-fat diet-induced and genetically obese mice, OPN expression was drastically up-regulated in AT (40 and 80-fold, respectively) but remained largely unaltered in liver (<2-fold). Moreover, OPN plasma concentrations remained unchanged in both murine models of obesity, suggesting a particular local but not systemic importance for OPN. OPN expression was strongly elevated also in the AT of obese patients compared with lean subjects in both omental and sc AT. In addition, we detected three OPN isoforms to be expressed in human AT and, strikingly, an obesity induced alteration of the OPN isoform expression pattern. Analysis of AT cellular fractions revealed that OPN is exceptionally highly expressed in AT macrophages in humans and mice. Moreover, OPN expression in AT macrophages was strongly up-regulated by obesity. In conclusion, our data point toward a specific local role of OPN in obese AT. Therefore, OPN could be a critical regulator in obesity induced AT inflammation and insulin resistance. 相似文献
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Oskar Kornasiewicz Marcin D?bski Michal Grat Barbara Lenartowicz Marta St?pnowska Anna Sza?as Ewa Bar-Andziak Marek Krawczyk 《Archives of Medical Science》2014,10(4):801-805
Introduction
Type 1 iodothyronine deiodinase (D1) converts thyroxin (T4) into tri-iodothyronine (T3). Strong evidence indicates that thyroid hormone metabolism is disturbed in neoplasms such as thyroid and breast cancer. However, there is limited data concerning the function of the D1 enzyme in liver tumors. We aimed to estimate the enzymatic activity of D1 in two different common liver tumors.Material and methods
We obtained 20 tumor samples from patients who had undergone a liver resection. Of the tissue samples, there were 13 benign lesions of focal nodular hyperplasia (FNH) and 7 malignant lesions of hepatocellular carcinomas (HCC). The D1 activity was assessed by measuring the amount of radioactive iodine released in reaction to D1-catalysed deiodination. Groups were compared by the Mann-Whitney non-parametrical test for independent trials, and the Kruskal Wallis test.Results
The enzymatic activity of D1 was not significantly altered in the FNH group (median = 536 fmol/mg of protein/min; p = 0.972) and HCC group (367 fmol/mg; p = 0.128) when compared to matched normal liver parenchyma controls (546 fmol/mg and 556 fmol/mg, respectively).Conclusions
Liver parenchyma expresses high levels of D1. The results clearly revealed that D1 activity was not significantly different between benign and malignant tumors (FNH and HCC) compared to healthy liver parenchyma cells. 相似文献48.
Felix Keil Peter Kalhs Oskar A. Haas Gerhard Fritsch Elisabeth Reiter Christine Mannhalter Klaus Lechner Gerda Leitner & Hildegard T. Greinix 《British journal of haematology》1997,97(1):161-164
We present a patient who underwent sibling allogeneic BMT because of refractory Ph+ve ALL and remained BCR-ABL-positive after marrow grafting. Haemopoietic precursor cells were predominantly BCR-ABL-negative and of donor origin. In T cells an exclusively donor genotype was demonstrated. Despite donor leucocyte infusion (DLI), 20 weeks after BMT BCR-ABL fusion mRNA increased in semiquantitative polymerase chain reaction and leukaemic infiltration of the patient's bone marrow was seen. After a second course of DLI the patient achieved sustained molecular remission but he developed severe graft-versus-host disease (GvHD) and died from bacterial sepsis 9 months after DLI. 相似文献
49.
Svein Oskar Frigstad Marte Høivik Jørgen Jahnsen Sandra Rinne Dahl Milada Cvancarova Tore Grimstad 《Scandinavian journal of gastroenterology》2017,52(1):100-106
Background and aim: Vitamin D deficiency is common in inflammatory bowel disease (IBD). The aims of the present study were to determine the prevalence of vitamin D deficiency and to identify clinical and epidemiological variables associated with vitamin D deficiency in an outpatient population with IBD.Methods: Participants were recruited from nine hospitals in the southeastern and western regions of Norway as part of an observational, multicentre study from March 2013 to April 2014. Clinical and epidemiological data were collected by interview and from medical records. All analyses of serum 25-hydroxyvitamin D (25-OH-D) were performed in the same laboratory.Results: In total, 49% (200/408) of the patients had a 25-OH-D concentration <50?nmol/L, including 53% (122/230) of the Crohn’s disease (CD) patients and 44% (78/178) of the ulcerative colitis (UC) patients. In CD patients, disease activity, measured as the HBI, was inversely associated with vitamin D deficiency. No such association was observed with the Simple Clinical Colitis Activity Index (SCCAI) scores in UC, but in UC patients, vitamin D deficiency was associated with elevated faecal calprotectin >100?mg/kg. In patients with CD, there were significantly more relapses during the previous year in patients with vitamin D deficiency.Conclusions: Vitamin D deficiency was common, especially in CD, and was associated with increased disease activity, a relapsing disease course and higher inflammatory activity. 相似文献
50.
BACKGROUND: The differential sensitivity of tumor cells to TRAIL-induced apoptosis may be mediated by different intracellular inhibitors of apoptosis, and only a few reports have described the pathway(s) that are activated in response to TRAIL in prostate cells. METHODS: LNCaP was transfected with a dominant-negative form of FADD (FADD-DN) and cells were selected in the presence of hygromycin. Cell viability was estimated by calcein assay. Apoptosis was estimated by caspase activation using both fluorogenic substrates and Western blot analysis of activated caspases. To detect cytochrome c release, mitochondria-free cytosol was prepared and Western blot analysis was performed. RESULTS: LNCaP is resistant to TRAIL but TRAIL transiently induces DEVDase activity and activation of caspase-8; caspase-2, -3, -7, and -9 were not activated. Wortmannin, an inhibitor of the PI3K/Akt pathway, converted the phenotype of LNCaP from TRAIL-resistant to -sensitive. In the presence of wortmannin TRAIL induced activation of caspase-2, -3, -7, -8, and -9, as well as dissipation of mitochondrial transmembrane potential and release of cyto-chrome c from mitochondria into the cytosol. In addition, combined TRAIL and wortmannin treatment resulted in cleavage of several proteins: PARP, Akt, p21/WAF1, and MDM2 as well as dephosphorylation of Akt. The proteolysis of p21/WAFI and Akt, which are known survival factors, presumably amplify the apoptotic cascade in LNCaP. Transfection of FADD-DN in LNCaP resulted in inhibition of caspase activation as well as in resistance to combined treatment with TRAIL and wortmannin. CONCLUSIONS: These results suggest that caspase-8 activation is necessary but not sufficient for TRAIL-mediated apoptosis and is presumably blocked downstream of caspase-8 by the PI3K/Akt pathway. 相似文献