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1.
Melanie A. Krook Julie W. Reeser Gabrielle Ernst Hannah Barker Max Wilberding Gary Li Hui-Zi Chen Sameek Roychowdhury 《British journal of cancer》2021,124(5):880
Fibroblast growth factor receptors (FGFRs) are aberrantly activated through single-nucleotide variants, gene fusions and copy number amplifications in 5–10% of all human cancers, although this frequency increases to 10–30% in urothelial carcinoma and intrahepatic cholangiocarcinoma. We begin this review by highlighting the diversity of FGFR genomic alterations identified in human cancers and the current challenges associated with the development of clinical-grade molecular diagnostic tests to accurately detect these alterations in the tissue and blood of patients. The past decade has seen significant advancements in the development of FGFR-targeted therapies, which include selective, non-selective and covalent small-molecule inhibitors, as well as monoclonal antibodies against the receptors. We describe the expanding landscape of anti-FGFR therapies that are being assessed in early phase and randomised controlled clinical trials, such as erdafitinib and pemigatinib, which are approved by the Food and Drug Administration for the treatment of FGFR3-mutated urothelial carcinoma and FGFR2-fusion cholangiocarcinoma, respectively. However, despite initial sensitivity to FGFR inhibition, acquired drug resistance leading to cancer progression develops in most patients. This phenomenon underscores the need to clearly delineate tumour-intrinsic and tumour-extrinsic mechanisms of resistance to facilitate the development of second-generation FGFR inhibitors and novel treatment strategies beyond progression on targeted therapy.Subject terms: Cancer, Cancer 相似文献
2.
The association between family affluence and smoking among 15‐year‐old adolescents in 33 European countries,Israel and Canada: the role of national wealth
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Alexander Stoff MD ; Angel A. Rivera PhD ; N. S. Banerjee PhD ; J. Michael Mathis PhD ; Antonio Espinosa-de-los-Monteros MD ; Long P. Le PhD ; Jorge I. De la Torre MD ; Luis O. Vasconez MD ; Thomas R. Broker PhD ; Dirk F. Richter MD ; Mariam A. Stoff-Khalili MD ; David T. Curiel MD PhD 《Wound repair and regeneration》2006,14(5):608-617
Genetically modified keratinocytes and fibroblasts are suitable for delivery of therapeutic genes capable of modifying the wound healing process. However, efficient gene delivery is a prerequisite for successful gene therapy of wounds. Whereas adenoviral vectors (Ads) exhibit superior levels of in vivo gene transfer, their transductional efficiency to cells resident within wounds may nonetheless be suboptimal, due to deficiency of the primary adenovirus receptor, coxsackie-adenovirus receptor (CAR). We explored CAR-independent transduction to fibroblasts and keratinocytes using a panel of CAR-independent fiber-modified Ads to determine enhancement of infectivity. These fiber-modified adenoviral vectors included Ad 3 knob (Ad5/3), canine Ad serotype 2 knob (Ad5CAV-2), RGD (Ad5.RGD), polylysine (Ad5.pK7), or both RGD and polylysine (Ad5.RGD.pK7). To evaluate whether transduction efficiencies of the fiber-modified adenoviral vectors correlated with the expression of their putative receptors on keratinocytes and fibroblasts, we analyzed the mRNA levels of CAR, alpha upsilon integrin, syndecan-1, and glypican-1 using quantitative polymerase chain reaction. Analysis of luciferase and green fluorescent protein transgene expression showed superior transduction efficiency of Ad5.pK7 in keratinocytes and Ad5.RGD.pK7 in fibroblasts. mRNA expression of alpha upsilon integrin, syndecan-1 and glypican-1 was significantly higher in primary fibroblasts than CAR. In keratinocytes, syndecan-1 expression was significantly higher than all the other receptors tested. Significant infectivity enhancement was achieved in keratinocytes and fibroblasts using fiber-modified adenoviral vectors. These strategies to enhance infectivity may help to achieve higher clinical efficacy of wound gene therapy. 相似文献
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Peter Chiba Barbara Tell Walter Jger Elisabeth Richter Manuela Hitzlera Gerhard Ecker 《Archiv der Pharmazie》1997,330(11):343-347
A series of 5-hydroxy and 5-benzyloxy analogs of the antiarrhythmic and multidrug resistance (MDR) modulating drug propafenone was synthesized and the MDR-modulating activity of the compounds was evaluated using a daunomycin efflux assay system. The key step of the synthesis is the selective reduction of the double bond in 1 without cleavage of the benzyl group thus leading to the phenol 3 . Alkylation with epichlorohydrine followed by nucleophilic epoxide ring opening gave the benzylated target compounds 5a–d . Subsequent cleavage of the benzyl group gave the 5-hydroxy analogs 6a–d . Structure activity relationship studies showed, that the 5-hydroxy derivates 6a–d fit the log P/log potency correlation line previously established for a series of propafenone analogs. In contrast, all four 5-benzyloxy analogs 5a–d showed almost identical EC50 values, independent of their log P value. 相似文献
8.
W. Nörenberg Ernst Schöffel Bela Szabo Klaus Starke 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):159-165
The aim of the study was to subclassify the soma-dendritic α2-autoreceptors in the locus coeruleus (LC) of the rat by means of antagonists. To this end, the frequency of spontaneous action
potentials was recorded extracellularly from single LC neurones in brain slices. The neurones fired spontaneously at an average
rate of 1 Hz. The selective α2-adrenoceptor agonist 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) and noradrenaline decreased the action potential
discharge with IC50 values of 5 and 510 nM, respectively. The concentration-inhibition curves of UK 14,304 and noradrenaline were shifted to the
right by phentolamine (0.15 μM) and rauwolscine (0.15 μM) but not by prazosin (1 μM). Apparent K
d values of phentolamine were 17 nM (against UK 14,304) and 20 nM (against noradrenaline). Apparent K
d values of rauwolscine were 47 nM (against UK 14,304) and 70 nM (against noradrenaline). (+)-Oxaprotiline (1 μM) suppressed
the firing of the neurones within 10 to 33 min. In the continued presence of oxaprotiline, phentolamine and rauwolscine restored
firing with EC50 values of 120 and 250 nM, respectively. Prazosin (1 μM) again was ineffective. All three antagonist affinity estimates –
against UK 14,304, exogenous noradrenaline and endogenous noradrenaline (that accumulates in the extracellular space in the
presence of oxaprotiline) – yield an affinity order phentolamine > rauwolscine >> prazosin, prazosin being ineffective even
at a concentration of 1 μM. These findings identify the soma-dendritic α2-autoreceptors of the LC as the rat variant of the α2A/D-adrenoceptor, i.e. α2D. Not only presynaptic but also soma-dendritic α2-autoreceptors may at least predominantly be α2A/D throughout the nervous system.
Received: 3 March 1997 / Accepted: 21 April 1997 相似文献
9.
A study was carried out in order to document any abnormalities in the electro-encephalogram (EEG) that might appear in young adolescents who have deliberately inhaled the range of volatile substances loosely referred to as 'glue'. The EEGs of a group of 'street children' being assisted in a Johannesburg shelter were examined. The records were analysed for any clinical abnormalities and also subjected to spectral analysis in order to examine the overall characteristics of frequency, power and spatial distribution. The EEGs clearly revealed that, although at the time of the examination the subjects were ostensibly abstinent, both clinical and normative evidence of continuing brain disturbance was present. It was concluded that glue sniffing is likely to have long term electrocerebral sequelae. 相似文献
10.
Martin Heine Evgeni Ponimaskin Ulf Bickmeyer Diethelm W. Richter 《Pflügers Archiv : European journal of physiology》2002,443(3):418-426
The HvCNG channel from the moth Heliothis virescens is highly sensitive to cAMP concentrations ranging between 0.1 microM and 5 microM. This HvCNG channel was over-expressed in Spodoptera frugiperda (Sf.9) cells to measure endogenous cAMP levels. Hyperpolarization-activated inward currents were measured in the whole-cell patch-clamp configuration with pipettes filled with different cAMP concentrations to calibrate the system. Varying the cAMP concentration between 0 microM and 100 microM in the pipette, the half-maximal activation voltage ( V1/2) was shifted by +28.5+/-1.7 mV. The activation time constant (tau(a)) was used as a parameter for cAMP quantification because it was independent of the expression level of HvCNG channels. tau(a) changed from 1106+/-60 ms at 0 microM cAMP to 265+/-7 ms at a saturating concentration of 1 mM cAMP. A dose-response relationship yielded values of 0.6 microM for the half-maximal cAMP concentration and 1.5 for the Hill coefficient. Activation of endogenous adenylyl cyclases by 50 microM forskolin induced an elevation of the cAMP level by about 1.6+/-0.2 microM. Co-expressions of HvCNG channels in combination with the mouse 5-HT4a- or 5-HT1A- receptors and the corresponding Gs- or Gi-proteins were successful and allowed us to also verify receptor-induced changes of the cAMP level. Stimulation of m5-HT4a-receptors by 0.1 microM 5-HT induced an increase of cAMP of about 4.6+/-1.5 microM, whereas cAMP levels decreased from a control value of 1+/-0.2 microM to 0.41+/-0.1 microM after stimulation of the m5-HT1A-receptors. 相似文献