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Epstein-Barr virus latent membrane protein 1 activation of NF-kappaB through IRAK1 and TRAF6 总被引:1,自引:0,他引:1
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Luftig M Prinarakis E Yasui T Tsichritzis T Cahir-McFarland E Inoue J Nakano H Mak TW Yeh WC Li X Akira S Suzuki N Suzuki S Mosialos G Kieff E 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(26):15595-15600
Epstein-Barr virus latent membrane protein 1 (LMP1) activation of NF-kappaB is critical for Epstein-Barr virus-infected B lymphocyte survival. LMP1 activates the IkappaB kinase complex and NF-kappaB through two cytoplasmic signaling domains that engage tumor necrosis factor receptor-associated factor (TRAF)1/2/3/5 or TRADD and RIP. We now use cells lacking expression of TRAF2, TRAF5, TRAF6, IKKalpha, IKKbeta, IKKgamma, TAB2, IL-1 receptor-associated kinase (IRAK)1, or IRAK4 to assess their roles in LMP1-mediated NF-kappaB activation. LMP1-induced RelA nuclear translocation was similar in IKKalpha knockout (KO) and WT murine embryo fibroblasts (MEFs) but substantially deficient in IKKbeta KO MEFs. NF-kappaB-dependent promoter responses were also substantially deficient in IKKbeta KO MEFs but were hyperactive in IKKalpha KO MEFs. More surprisingly, NF-kappaB responses were near normal in TRAF2 and TRAF5 double-KO MEFs, IKKgamma KO MEFs, TAB2 KO MEFs, and IRAK4 KO MEFs but were highly deficient in TRAF6 KO MEFs and IRAK1 KO HEK293 cells. Consistent with the importance of TRAF6, LMP1-induced NF-kappaB activation in HEK293 cells was inhibited by expression of dominant-negative TAB2 and Ubc13 alleles. These data extend a role for IKKalpha in IKKbeta regulation, identify an unusual IKKbeta-dependent and IKKgamma-independent NF-kappaB activation, and indicate that IRAK1 and TRAF6 are essential for LMP1-induced NF-kappaB activation. 相似文献
35.
Nicholas V. Sarlis Efthimios S. Skordas Panayiotis A. Varotsos Toshiyasu Nagao Masashi Kamogawa Seiya Uyeda 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(4):986-989
Using the Japan Meteorological Agency earthquake catalog, we investigate the seismicity variations before major earthquakes in the Japanese region. We apply natural time, the new time frame, for calculating the fluctuations, termed β, of a certain parameter of seismicity, termed κ1. In an earlier study, we found that β calculated for the entire Japanese region showed a minimum a few months before the shallow major earthquakes (magnitude larger than 7.6) that occurred in the region during the period from 1 January 1984 to 11 March 2011. In this study, by dividing the Japanese region into small areas, we carry out the β calculation on them. It was found that some small areas show β minimum almost simultaneously with the large area and such small areas clustered within a few hundred kilometers from the actual epicenter of the related main shocks. These results suggest that the present approach may help estimation of the epicentral location of forthcoming major earthquakes.In this study, we investigate the evolution of seismicity shortly before main shocks in the Japanese region, , using Japan Meteorological Agency (JMA) earthquake catalog as in ref 1. For this, we adopted the new time frame called natural time since our previous works using this time frame made the lead time of prediction as short as a few days (see below). For a time series comprising N earthquakes (EQs), the natural time χk is defined as χk = k/N, where k means the kth EQ with energy Qk (Fig. 1). Thus, the raw data for our investigation, to be read from the earthquake catalog, are χk = k/N and , where pk is the normalized energy. In natural time, we are interested in the order and energy of events but not in the time intervals between events.Open in a separate windowFig. 1.EQ sequence in (A) conventional time and (B) natural time. In B, Qk is given in units of the energy ε corresponding to a 3.5MJMA EQ.We first calculate a parameter called κ1, which is defined as follows (2, 3), from the catalog.[1]We start the calculation of κ1 at the time of initiation of Seismic Electric Signals (SES), the transient changes of the electric field of Earth that have long been successfully used for short-term EQ prediction (4, 5). The area to suffer a main shock is estimated on the basis of the selectivity map (4, 5) of the station that recorded the corresponding SES. Thus, we now have an area in which we count the small EQs of magnitude greater than or equal to a certain magnitude threshold that occur after the initiation of the SES. We then form time series of seismic events in natural time for this area each time a small EQ occurs, in other words, when the number of the events increases by one. The κ1 value for each time series is computed for the pairs (χk,pk) by considering that χk is “rescaled” to χk = k/(N +1) together with rescaling upon the occurrence of any additional event in the area. The resulting number of thus computed κ1 values is usually of the order 102 to 103 depending, of course, on the magnitude threshold adopted for the events that occurred after the SES initiation until the main shock occurrence. When we followed this procedure, it was found empirically that the values of κ1 converge to 0.07 a few days before main shocks. Thus, by using the date of convergence to 0.07 for prediction, the lead times, which were a few months to a few weeks or so by SES data alone, were made, although empirically, as short as a few days (6, 7). In fact, the prominent seismic swarm activity in 2000 in the Izu Island region, Japan, was preceded by a pronounced SES activity 2 mo before it, and the approach of κ1 to 0.07 was found a few days before the swarm onset (8). However, when SES data are not available, which is usually the case, it is not possible to follow the above procedure. To cope with this difficulty, in the previous work (1), we investigated the time change of the fluctuation of the κ1 values during a few preseismic months for each EQ (which we call target EQ) over the large area (Fig. 2A) for the period from 1 January 1984 to 11 March 2011, the day of M9.0 Tohoku EQ. Setting a threshold MJMA = 3.5 to assure data completeness of JMA catalog, we were left with 47,204 EQs in the concerned period of about 326 mo: ∼150 EQs per month. For calculating the β values, we chose 200 EQs before target EQs to cover the seismicity in almost one and a half months.Open in a separate windowFig. 2.(A) The 47,204 EQs with MJMA ≥ 3.5 that occurred during the period of our study. (B) Contours of the number of EQs per month within R = 250 km. Solid diamonds show the epicenters of six shallow EQs investigated in this study. (C) Contours of the natural time window W used in each of the 12,476 areas of radius R = 250 km with offset 0.1° from one another that have at least eight EQs per month.To obtain the fluctuation β of κ1, we need many values of κ1 for each target EQ. For this purpose, we first took an excerpt comprised of W successive EQs just before a target EQ from the seismic catalog. The number W was chosen to cover a period of a few months. For this excerpt, we form its subexcerpts of consecutive N = 6 EQs (since at least six EQs are needed (2) for obtaining reliable κ1) of energy Qj+k?1 and natural time χk = k/N each. Further, , and by sliding Sj over the excerpt of W EQs, (= W − 5), we calculate κ1 using Eq. 1 for each j. We repeat this calculation for , thus obtaining an ensemble of [(W − 4)(W − 5)]/2 (= 1 + 2 +…+ W − 5) κ1 values. Then, we compute the average μ(κ1) and the SD σ(κ1) of thus obtained ensemble of [(W − 4)(W − 5)]/2 κ1 values. The variability β of κ1 for this excerpt W is defined to be β ≡ σ(κ1)/μ(κ1) and is assigned to the (W + 1)th EQ, i.e., the target EQ.The time evolution of the β value can be pursued by sliding the excerpt through the EQ catalog. Namely, through the same process as above, β values assigned to (W + 2)th, (W + 3)th, … EQs in the catalog can be obtained.We found in ref. 1 that the fluctuation β of κ1 values exhibited minimum a few months before all of the six shallow EQs of magnitude larger than 7.6 that occurred in the study period. A minimum of β ≡ σ(κ1)/μ(κ1) means large average and/or small deviation of κ1 values (e.g., see ref. 9).In the present work, we calculate the β values for small areas before the six large EQs, which showed β minima of the large area. 相似文献
36.
Peter Ziegler Efthimios D Avgerinos Thomas Umscheid Theodosios Perdikides Wolf J Stelter 《Journal of endovascular therapy》2007,14(5):609-618
PURPOSE: To present a 7-year single-center clinical experience with fenestrated endografts and side branches. METHODS: Between April 1999 and August 2006, 63 patients (57 men; mean age 70.5+/-11.6 years, range 25-89) received custom-designed Zenith fenestrated endoprostheses for a variety of aneurysms (59 abdominal, 1 thoracoabdominal, and 3 thoracic). They were all unsuitable for standard EVAR owing to short aortic necks and high risk for open surgery. RESULTS: Nineteen tube grafts and 44 composite bifurcated grafts with a total of 122 fenestrations and 58 side branches were used. Technical success was achieved in 55 (87.3%) patients and in 118 (96.7%) vessels. Treatment success was 93.7%. The mean follow-up was 23+/-18 months (median 14, range 6-77). Overall, 9 (7.4%) visceral branches were lost: 4 intraoperative, 2 perioperative, and 3 late. There were 12 (19.0%) endoleaks identified: 5 (7.9%: 4 type Ia and 1 fenestration-related type III) primary and 7 (11.1%: 4 type II, 1 type I, and 2 type III) secondary endoleaks; 4 resolved, 4 were treated, and 4 are under observation. At 77 months, 75.3% of patients were free of a reintervention. All reinterventions were performed within the first 14 months. Fourteen cases of renal impairment were seen [6 permanent (only 1 on dialysis) and 8 transient]. One (1.6%) conversion and 1 (1.6%) rupture were recorded; aneurysm-related mortality was 4.8% (3/63). CONCLUSION: The favorable outcomes in this study, which encompasses the team's learning curve with fenestrated endografts and side branches, support the use of these devices in selected patients. 相似文献
37.
Effects of melatonin on proliferation of cancer cell lines 总被引:1,自引:0,他引:1
Konstantinos T. Papazisis Demetrios Kouretas George D. Geromichalos Efthimios Sivridis Olga K. Tsekreli Konstantinos A. Dimitriadis Alexander H. Kortsaris 《Journal of pineal research》1998,25(4):211-218
Papazisis KT, Kouretas D, Geromichalos GD, Sivridis E, Tsekreli OK, Dimitriadis KA, Kortsaris A.H. Effects of melatonin on proliferation of cancer cell lines. J. Pineal Res. 1998; 25:211–218. © Munksgaard, Copenhagen The pineal hormone melatonin has been reported to have in vitro antiproliferative effects on estrogen receptor-positive human breast cancer cell lines at concentrations near to plasma physiological concentrations (1 times 10-11 to 1 times 10-9 M). Its growth inhibitory actions have been thought to be linked to the estrogen-receptor system. We tested the cytotoxic effects of melatonin on MCF-7 and T47D human breast cancer cell lines by using the SRB (sulforhodamine-B), XTT-tetrazolium, and bromodeoxyuridine (BrdU) assays in 96-well microtiter plates. After a 3 or 4 day exposure, melatonin did not have any significant effect on breast cancer cell proliferation and survival in doses up to 1 times 10-4 M. Doses higher than 1 mM exhibited a potent cytotoxic effect, which was not mediated by the estrogen-receptor or by protein tyrosine kinases and was not specific for breast cancer cell lines. Intracellular glutathione levels did not seem to play any role in the sensitivity of breast cancer cells to melatonin, since the addition of L-buthionine-[S,R]-sulfoximine, ethacrynic acid, or exogenous glutathione did not modify our results. We conclude that under our experimental conditions melatonin has no inhibitory effects on human breast cancer cells at low (physiological or supraphysiological) concentrations. The different experimental procedures that were utilized in the present study can partially explain the divergence between our results and the literature. 相似文献
38.
Liver blood flow measurements obtained from both the liver surface and deep within the parenchyma,
were correlated in an effort to assess the usefulness of laser-Doppler flowmetry for non-invasive
monitoring of total liver blood flow, the probe being positioned on either the surface or within the liver
parenchyma.In 23 Wistar rats and 10 biliary surgery patients, anaesthetized prior to gallbladder removal, liver
microcirculation was measured at 4 points on the capsular surface, and consequently at 4 points deep
within the parenchyma, using probes connected to a laser-Doppler flowmeter. The findings revealed
that laser-Doppler measurements on the liver surface and within the parenchyma were well correlated,
as no statistically significant differences were found either in rats or humans. It is concluded that laser-
Doppler flowmetry for monitoring of total liver perfusion can be applied either on the capsular surface
or within the hepatic parenchyma. 相似文献
39.
Koukourakis MI Papazoglou D Giatromanolaki A Panagopoulos I Maltezos E Harris AL Gatter KC Sivridis E 《Lung cancer (Amsterdam, Netherlands)》2006,53(3):257-262
OBJECTIVES: In this study, we investigated whether polymorphisms of the HIF-1alpha gene may account for the patterns of HIF-1alpha protein expression in non-small cell lung carcinomas (NSCLC) and the expression of HIF-1alpha down-stream proteins. METHODS: Specific HIF-1alpha polymorphisms were assessed in a series of patients with NSCLC: (a) the C to T transition at nucleotide 1744 (position 2028 according to sequence with accession number , which gives rise to Pro/Ser variation at codon 582), (b) the G to A nucleotide substitution at point 1790 (position 2046 according to sequence with accession number , which gives rise to Ala/Thr variation at codon 588), and (c) the dinucleotide GT repeat polymorphism in intron 13. Immunohistochemistry for HIF-1alpha and down-stream proteins (VEGF, LDH-5, GLUT-1) was also performed in tumor material. RESULTS: A strong association of the P582S polymorphism and of GT repeat polymorphism higher than 14/14 with increased HIF-1alpha expression was noted. HIF-1alpha polymorphism did not relate to the expression of the HIF-1alpha downstream proteins analysed, but significant association of HIF-1alpha expression with LDH-5 was confirmed (p=0.008). CONCLUSIONS: HIF-1alpha polymorphisms may have an important impact on HIF-protein stability and, eventually, function. 相似文献
40.
Giatromanolaki A Sivridis E Koukourakis MI 《American journal of clinical oncology》2006,29(4):408-417
Angiogenesis is important for tumor growth and metastasis. This account reviews the clinicopathological studies conducted in the field of angiogenesis in colorectal cancer, the methods of assessing vascular-related characteristics in tissue sections and provides a background for the usefulness of antiangiogenic policies along with chemotherapy and radiotherapy. Highly angiogenic colorectal tumors are associated with aggressive histopathological features and poor patients' survival. Similarly, factors stimulating angiogenesis, such as vascular endothelial growth factor (VEGF), thymidine phosphorylase (TP), and others, are commonly related to increased vascular density (VD) and, therefore, to an unfavorable clinical course. Anti-VEGF agents have improved prognosis in patients with metastatic colorectal cancer, when added to standard chemotherapy. It is expected that, in addition to adjuvant chemotherapy and radiotherapy, agents blocking the stimulatory effect of VEGF on endothelial cells would prove beneficial to the patient. 相似文献