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951.
YR Kim JS Kim YH Min DH Yoon HJ Shin YC Mun Y Park YR Do SH Jeong JS Park SY Oh S Lee EK Park JS Jang WS Lee HW Lee H Eom JS Ahn J Jeong SK Baek SJ Kim WS Kim C Suh 《Journal of hematology & oncology》2012,5(1):49
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value. 相似文献
952.
The pitch-loblolly pine hybrid (Pinus rigida × P. taeda) has useful characteristics of the parents, but its exploitation is hindered by restrictions of conventional breeding and
propagation methods. This study was undertaken to establish an effective in vitro system for propagating pitch-loblolly hybrid
pine through somatic embryogenesis and to unravel the relationship between the efficiency of embryogenic tissue initiation
and zygotic embryo development. To initiate embryogenic tissue, megagametophytes of developing seeds were used as explants.
Seeds were collected weekly, examined, and tested during June and July 2004. The medium and seed collection date were the
most important factors for the successful somatic embryogenesis of P. rigida × P. taeda. Five embryogenic lines were obtained using a modified P. taeda basal medium, and the highest initiation rate was 0.55%, for seeds collected in 2 weeks, between July 3 and 16. Histological
observation revealed that zygotic embryos of those seeds were mostly at the proembryonic stage or in transition to precotyledonary
stages. For the successful maturation of somatic embryos, abscisic acid and gellan gum were needed in the medium. The results
show that, although further tests and development are required, somatic embryogenesis could provide a viable option for propagating
P. rigida × P. taeda hybrids. 相似文献
953.
ABSTRACT: BACKGROUND: In sleep efficiency monitoring system, actigraphy is the simplest and most commonly used device. However, low specificity to wakefulness of actigraphy was revealed in previous studies. In this study, we assumed that sleep/wake estimation using actigraphy and electromyography (EMG) signals would show different patterns. Furthermore, each EMG pattern in two states (sleep, wake during sleep) was analysed. Finally, we proposed two types of method for the estimation of sleep/wake patterns using only EMG signals from anterior tibialis muscles and the results were compared with PSG data. METHODS: Seven healthy subjects and five patients (2 obstructive sleep apnea, 3 periodic limb movement disorder) participated in this study. Night time polysomnography (PSG) recordings were conducted, and electrooculogram, EMG, electroencephalogram, electrocardiogram, and respiration data were collected. Time domain analysis and frequency domain analysis were applied to estimate the sleep/wake patterns. Each method was based on changes in amplitude or spectrum (total power) of anterior tibialis electromyography signals during the transition from the sleep state to the wake state. To obtain the results, leave-one-out-cross-validation technique was adopted. RESULTS: Total sleep time of the each group was about 8 hours. For healthy subjects, the mean epoch-by-epoch results between time domain analysis and PSG data were 99%, 71%, 80% and 0.64 (sensitivity, specificity, accuracy and kappa value), respectively. For frequency domain analysis, the corresponding values were 99%, 73%, 81% and 0.67, respectively. Absolute and relative differences between sleep efficiency index from PSG and our methods were 0.8 and 0.8% (for frequency domain analysis). In patients with sleep-related disorder, our proposed methods revealed the substantial agreement (kappa > 0.61) for OSA patients and moderate or fair agreement for PLMD patients. CONCLUSIONS: The results of our proposed methods were comparable to those of PSG. The time and frequency domain analyses showed the similar sleep/wake estimation performance. 相似文献
954.
Min Hwa Shin Ming Yuan Hao Zhang Joseph B. Margolick Mihoko Kai 《Cell cycle (Georgetown, Tex.)》2012,11(9):1796-1803
Upon genotoxic stress and during normal S phase, ATM phosphorylates the checkpoint clamp protein Rad9 in a manner that depends on Ser272. Ser272 is the only known ATM-dependent phosphorylation site in human Rad9. However, Ser272 phosphorylation is not required for survival or checkpoint activation after DNA damage. The physiological function of Ser272 remains elusive. Here, we show that ATM-dependent Rad9Ser272 phosphorylation requires the MRN complex and controls repair pathways. Furthermore, the mutant cells accumulate large numbers of chromosome breaks and induce gross chromosomal rearrangements. Our findings establish a new and unexpected role for ATM: it phosphorylates the checkpoint clamp in order to control repair pathways, thereby maintaining genomic integrity during unperturbed cell cycle and upon DNA damage. 相似文献
955.
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957.
CD34+ cord blood cells can be reprogrammed effectively on dishes coated with a synthetic RGD motif polymer (PronectinF?) using a temperature sensitive Sendai virus vector (SeV TS7) carrying reprogramming factors OCT3/4, SOX2, KLF4 and c-MYC. Dish-shaped human ES cell-like colonies emerged in serum-free primate ES cell medium (supplemented with bFGF) in 20% O2 culture conditions. The copy numbers of SeV TS7 vectors in the cytoplasm were drastically reduced by a temperature shift at 38°C for three days. Then, single cells from colonies were seeded on PronectinF?-coated 96-well plates and cultured under na?ve culture conditions (N2B27-based medium supplemented with LIF, forskolin, a MAPK inhibitor, and a GSK inhibitor in 5% O2) for cloning purpose. Dome-shaped mouse ES cell-like colonies from single cells emerged on PronectinF?-coated dishes. These cells were collected and cultured again in primate ES cell medium supplemented with bFGF in 20% O2 and maintained on PronectinF?-coated dishes. Cells were assessed for reprogramming, including the absence of residual SeV and their potential for three germ layer differentiation. Generation of virus-free induced pluripotent stem cell (iPSC) clones from single cells under feeder-free conditions will solve some of the safety concerns related to use of xeno- or allogeneic-material in culture, and contribute to the characterization and the standardization of iPS cells intended for use in a clinical setting. 相似文献
958.
BACKGROUND: Optogenetic techniques using light-driven ion channels or ion pumps for controlling excitable cells have greatly facilitated the investigation of nervous systems in vivo. A model organism, C. elegans, with its small transparent body and well-characterized neural circuits, is especially suitable for optogenetic analyses. METHODOLOGY/PRINCIPAL FINDINGS: We describe the application of archaerhodopsin-3 (Arch), a recently reported optical neuronal silencer, to C. elegans. Arch::GFP expressed either in all neurons or body wall muscles of the entire body by means of transgenes were localized, at least partially, to the cell membrane without adverse effects, and caused locomotory paralysis of worms when illuminated by green light (550 nm). Pan-neuronal expression of Arch endowed worms with quick and sustained responsiveness to such light. Worms reliably responded to repeated periods of illumination and non-illumination, and remained paralyzed under continuous illumination for 30 seconds. Worms expressing Arch in different subsets of motor neurons exhibited distinct defects in the locomotory behavior under green light: selective silencing of A-type motor neurons affected backward movement while silencing of B-type motor neurons affected forward movement more severely. Our experiments using a heat-shock-mediated induction system also indicate that Arch becomes fully functional only 12 hours after induction and remains functional for more than 24 hour. CONCLUSIONS/SGNIFICANCE: Arch can be used for silencing neurons and muscles, and may be a useful alternative to currently widely used halorhodopsin (NpHR) in optogenetic studies of C. elegans. 相似文献
959.
Hofstetter CP Burkhardt JK Shin BJ Gürsel DB Mubita L Gorrepati R Brennan C Holland EC Boockvar JA 《PloS one》2012,7(1):e30059
Purpose
The hypoxic microenvironment of glioblastoma multiforme (GBM) is thought to increase resistance to cancer therapies. Recent evidence suggests that hypoxia induces protein phosphatase 2A (PP2A), a regulator of cell cycle and cell death. The effects of PP2A on GBM tumor cell proliferation and survival during hypoxic conditions have not been studied.Experimental Design
Expression of PP2A subunits and HIF-α proteins was measured in 65 high-grade astrocytoma and 18 non-neoplastic surgical brain specimens by western blotting. PP2A activity was measured by an immunoprecipitation assay. For in vitro experiments, GBM-derived tumor stem cell-like cells (TSCs) were exposed to severe hypoxia produced by either CoCl2 or 1% O2. PP2A activity was inhibited either by okadaic acid or by shRNA depletion of the PP2A C subunit. Effects of PP2A activity on cell cycle progression and cell survival during hypoxic conditions were assessed using flow cytometry.Results
In our patient cohort, PP2A activity was positively correlated with HIF-1∝ protein expression (P = 0.002). Patients with PP2A activity levels above 160 pMP had significantly worse survival compared to patients with levels below this threshold (P = 0.002). PP2A activity was an independent predictor of survival on multivariable analysis (P = 0.009). In our in vitro experiments, we confirmed that severe hypoxia induces PP2A activity in TSCs 6 hours after onset of exposure. PP2A activity mediated G1/S phase growth inhibition and reduced cellular ATP consumption in hypoxic TSCs. Conversely, inhibition of PP2A activity led to increased cell proliferation, exhaustion of intracellular ATP, and accelerated P53-independent cell death of hypoxic TSCs.Conclusions
Our results suggest that PP2A activity predicts poor survival in GBM. PP2A appears to reduce the metabolic demand of hypoxic TSCs and enhances tumor cell survival. Modulation of PP2A may be a potential target for cancer therapy. 相似文献960.
R Hashim AM Khatib G Enwere JK Park R Reyburn M Ali NY Chang DR Kim B Ley K Thriemer AL Lopez JD Clemens JL Deen S Shin C Schaetti R Hutubessy MT Aguado MP Kieny D Sack S Obaro AJ Shaame SM Ali AA Saleh L von Seidlein MS Jiddawi 《PLoS neglected tropical diseases》2012,6(7):e1743