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971.
Luminescent properties of Ca3SiO4Cl2 co‐doped with Ce3+ and Eu2+ for near‐ultraviolet light‐emitting diodes 下载免费PDF全文
Ca3SiO4Cl2 co‐doped with Ce3+,Eu2+ was prepared by high temperature reaction. The structure, luminescent properties and the energy transfer process of Ca3SiO4Cl2: Ce3+,Eu2+ were investigated. Eu2+ ions can give enhanced green emission through Ce3+ → Eu2+ energy transfer in these phosphors. The green phosphor Ca2.9775SiO4Cl2:0.0045Ce3+,0.018Eu2+ showed intense green emission with broader excitation in the near‐ultraviolet light range. A green light‐emitting diode (LED) based on this phosphor was made, and bright green light from this green LED could be observed by the naked eye under 20 mA current excitation. Hence it is considered to be a good candidate for the green component of a three‐band white LED. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
972.
David M Albala Jerome B Riebman Richard Kocharian Bogdan Ilie John Albanese Jessica Shen Liza Ovington Jonathan Batiller 《Reviews in urology》2015,17(1):25-30
In the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery, their effectiveness and safety have since been demonstrated to extend to a wide array of procedures. Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site in order to achieve hemostasis. However, many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. This subanalysis compares the safety and effectiveness of a fibrin sealant versus an absorbable hemostat for achieving hemostasis during urologic procedures with mild to moderate bleeding.Key words: Hemostasis, Hemostatics, Fibrin tissue adhesive, Urologic surgical procedures, Surgical techniqueIn the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery,1 their effectiveness and safety have since been demonstrated to extend to a wide array of procedures, including cardiovascular, gastrointestinal, pneumothoracic, neurologic, urologic, otolaryngologic, dental, and reconstructive surgeries.2,3 Within the field of urology, fibrin sealants have been used to manage bleeding from renal trauma,4 as well as to facilitate hemostasis during renal surgeries, including partial nephrectomies.5–7Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site (TBS) in order to achieve hemostasis.3 Many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. For example, in an observational study (N = 4374), the antifibrinolytic aprotinin was associated with an increased risk of long-term mortality within 5 years following coronary artery bypass graft surgery.8 Furthermore, repeated exposure to aprotinin may lead to allergic or potentially fatal anaphylactic reactions.9–11 For this reason, the US Food and Drug Administration (FDA) issued an alert in 2006 indicating that caution should be used when using aprotinin in patients with a history of previous exposure to the product.12 Tranexamic acid, another antifibrinolytic present in some commercial fibrin sealants, has been associated with alterations in neural tissue growth and adherence.13 Because of the risk of cerebral neurologic toxicity, fibrin sealants containing tranexamic acid are contraindicated for use in neurosurgery or in surgical procedures during which contact with cerebrospinal fluid or dura mater may occur.14In a phase III, randomized, single-blind, parallel-group, multicenter study,15 the fibrin sealant CROSSEAL™ (Ethicon, Inc., Somerville, NJ) significantly reduced the time to hemostasis during liver resection surgery compared with conventional hemostatic techniques. EVICEL® Fibrin Sealant (Human) (Ethicon, Inc.), the successor of CROSSEAL, requires no antifibrinolytic additive and is therefore both aprotinin and tranexamic acid free, and achieves hemostasis using exclusively human components.16 The effectiveness and safety of this fibrin sealant for hemostasis in soft tissue during elective retroperitoneal or intra-abdominal surgery were compared with an absorbable hemostat (SURGICEL® Absorbable Hemostat; Ethicon, Inc.) in a randomized, active-controlled, multicenter study.17 This article describes a subanalysis of data from the largest patient subgroup from that study, and evaluates the effectiveness and safety of a fibrin sealant versus an absorbable hemostat for patients who underwent urologic surgical procedures. 相似文献
973.
974.
Yao-An Shen Chia-Yu Wang Yi-Tao Hsieh Yann-Jang Chen Yau-Huei Wei 《Cell cycle (Georgetown, Tex.)》2015,14(1):86-98
Cancer stem cells (CSCs) represent a subpopulation of tumor cells endowed with
self-renewal capacity and are considered as an underlying cause of tumor recurrence and
metastasis. The metabolic signatures of CSCs and the mechanisms involved in the regulation
of their stem cell-like properties still remain elusive. We utilized nasopharyngeal
carcinoma (NPC) CSCs as a model to dissect their metabolic signatures and found that CSCs
underwent metabolic shift and mitochondrial resetting distinguished from their
differentiated counterparts. In metabolic shift, CSCs showed a greater reliance on
glycolysis for energy supply compared with the parental cells. In mitochondrial resetting,
the quantity and function of mitochondria of CSCs were modulated by the biogenesis of the
organelles, and the round-shaped mitochondria were distributed in a peri-nuclear manner
similar to those seen in the stem cells. In addition, we blocked the glycolytic pathway,
increased the ROS levels, and depolarized mitochondrial membranes of CSCs, respectively,
and examined the effects of these metabolic factors on CSC properties. Intriguingly, the
properties of CSCs were curbed when we redirected the quintessential metabolic
reprogramming, which indicates that the plasticity of energy metabolism regulated the
balance between acquisition and loss of the stemness status. Taken together, we suggest
that metabolic reprogramming is critical for CSCs to sustain self-renewal, deter from
differentiation and enhance the antioxidant defense mechanism. Characterization of
metabolic reprogramming governing CSC properties is paramount to the design of novel
therapeutic strategies through metabolic intervention of CSCs. 相似文献
975.
976.
Fu-Zheng Wei Ziyang Cao Xi Wang Hui Wang Mu-Yan Cai Tingting Li Naoko Hattori Donglai Wang Yipeng Du Boyan Song Lin-Lin Cao Changchun Shen Lina Wang Haiying Wang Yang Yang Dan Xie Fan Wang Toshikazu Ushijima Ying Zhao Wei-Guo Zhu 《Autophagy》2015,11(12):2309-2322
Macroautophagy is an evolutionarily conserved cellular process involved in the clearance of proteins and organelles. Although the autophagy regulation machinery has been widely studied, the key epigenetic control of autophagy process still remains unknown. Here we report that the methyltransferase EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) epigenetically represses several negative regulators of the MTOR (mechanistic target of rapamycin [serine/threonine kinase]) pathway, such as TSC2, RHOA, DEPTOR, FKBP11, RGS16 and GPI. EZH2 was recruited to these genes promoters via MTA2 (metastasis associated 1 family, member 2), a component of the nucleosome remodeling and histone deacetylase (NuRD) complex. MTA2 was identified as a new chromatin binding protein whose association with chromatin facilitated the subsequent recruitment of EZH2 to silenced targeted genes, especially TSC2. Downregulation of TSC2 (tuberous sclerosis 2) by EZH2 elicited MTOR activation, which in turn modulated subsequent MTOR pathway-related events, including inhibition of autophagy. In human colorectal carcinoma (CRC) tissues, the expression of MTA2 and EZH2 correlated negatively with expression of TSC2, which reveals a novel link among epigenetic regulation, the MTOR pathway, autophagy induction, and tumorigenesis. 相似文献
977.
978.
Tingting Hu Shuqiang Weng Wenqing Tang Ruyi Xue She Chen Guoxiang Cai Yu Cai Xizhong Shen Si Zhang Ling Dong 《PloS one》2015,10(5)
MethodsWe used Western blotting and immunohistochemistry to examine BIRC6 expression in 7 CRC cell lines and 126 CRC clinical samples. We determined the biological significance of BIRC6 in CRC cell lines by a lentivirus-mediated silencing method.ResultsWe reported that BIRC6 was overexpressed in CRC cell lines and clinical CRC tissues. BIRC6 overexpression was correlated with tumor size and invasion depth of CRC. BIRC6 overexpression is associated with worse overall survival (OS) (P = 0.001) and shorter disease-free survival (DFS) (P = 0.010). BIRC6 knockdown inhibited cell proliferation, arrested cell cycle at S phase, downregulated cyclin A2, B1, D1 and E1 levels, and sensitized CRC cells to chemotherapy in vitro and in vivo.ConclusionsTaken together, these data suggests that BIRC6 overexpression is a predictor of poor prognosis in colorectal cancer and BIRC6 could be a potential target of CRC therapy. 相似文献
979.
Background
Bipolar disorder types I (BD I) and II (BD II) behave differently in clinical manifestations, normal personality traits, responses to pharmacotherapies, biochemical backgrounds and neuroimaging activations. How the varied emotional states of BD I and II are related to the comorbid personality disorders remains to be settled.Methods
We therefore administered the Plutchick – van Praag Depression Inventory (PVP), the Mood Disorder Questionnaire (MDQ), the Hypomanic Checklist-32 (HCL-32), and the Parker Personality Measure (PERM) in 37 patients with BD I, 34 BD II, and in 76 healthy volunteers.Results
Compared to the healthy volunteers, patients with BD I and II scored higher on some PERM styles, PVP, MDQ and HCL-32 scales. In BD I, the PERM Borderline style predicted the PVP scale; and Antisocial predicted HCL-32. In BD II, Borderline, Dependant, Paranoid (-) and Schizoid (-) predicted PVP; Borderline predicted MDQ; Passive-Aggressive and Schizoid (-) predicted HCL-32. In controls, Borderline and Narcissistic (-) predicted PVP; Borderline and Dependant (-) predicted MDQ.Conclusion
Besides confirming the different predictability of the 11 functioning styles of personality disorder to BD I and II, we found that the prediction was more common in BD II, which might underlie its higher risk of suicide and poorer treatment outcome. 相似文献980.
Na Shen Cheng Liu Jiaoyuan Li Xueqin Chen Yang Yang Ying Zhu Yajie Gong Jing Gong Rong Zhong Liming Cheng Xiaoping Miao 《PloS one》2015,10(3)
It is well-established that abnormal protein phosphorylation could play an essential role in tumorgenesis by disrupting a variety of physiological processes such as cell growth, signal transduction and cell motility. Moreover, increasing numbers of phosphorylation-related variants have been identified in association with cancers. ADD1 (α-adducin), a versatile protein expressed ubiquitously in eukaryotes, exerts an important influence on membrane cytoskeleton, cell proliferation and cell-cell communication. Recently, a missense variant at the codon of ADD1’s phosphorylation site, rs4963 (Ser586Cys), was reported to modify the risk of non-cardia gastric cancer. To explore the role of ADD1-rs4963 in colorectal cancer (CRC), we conducted a case-control study with a total of 1054 CRC cases and 1128 matched controls in a Chinese population. After adjustment for variables including age, gender, smoking and drinking, it was demonstrated that this variant significantly conferred susceptibility to CRC (G versus C: OR = 1.16, 95% CI = 1.03–1.31, P = 0.016; CG versus CC: OR = 1.25, 95% CI = 1.02–1.55, P = 0.036; GG versus CC: OR = 1.35, 95% CI = 1.06–1.72, P = 0.015). We further investigated the interaction of ADD1-rs4963 with smoking or drinking exposure, but found no significant result. This study is the first report of an association between ADD1 and CRC risk, promoting our knowledge of the genetics of CRC. 相似文献