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21.
扁桃体切除术是耳鼻咽喉科最常见的手术之一,临床上治疗由于扁桃体肥大所致的儿童睡眠阻塞性呼吸暂停综合征,最常用的手术方式为双侧扁桃体切除术。扁桃体在儿童生长发育过程中具有重要的免疫功能,完全切除扁桃体对儿童的免疫功能具有一定的影响。且扁桃体全部切除术后常见一些并发症如出血及疼痛,这使得许多学者提出了扁桃体部分切除术。扁桃体部分切除术较扁桃体全部切除术相比,手术时间短、术后并发症少,在缓解儿童阻塞症状的同时,保留了一部分扁桃体,对于免疫功能也有一定的保留。本文将从扁桃体部分切除术治疗儿童睡眠呼吸暂停综合征的临床疗效以及术后出血、术后疼痛方面作一综述,为扁桃体部分切除术应用于临床提供合理依据。 相似文献
22.
J. Falk-Vairant P. Corrèges L. Eder-Colli N. Salem F. M. Meunier B. Lesbats F. Loctin †M. Synguelakis M. Israël Y. Dunant 《Journal of neurochemistry》1996,66(3):1322-1325
Abstract: Transmitter release was elicited in two ways from cultured cells filled with acetylcholine: (a) in a biochemical assay by successive addition of a calcium ionophore and calcium and (b) electrophysiologically, by electrical stimulation of individual cells and real-time recording with an embryonic Xenopus myocyte. Glioma C6-Bu-1 cells were found to be competent for Ca2+ -dependent and quantal release. In contrast, no release could be elicited from mouse neuroblastoma N18TG-2 cells. However, acetylcholine release could be restored when N18TG-2 cells were transfected with a plasmid coding for mediatophore. Mediatophore is a protein of nerve terminal membranes purified from the Torpedo electric organ on the basis of its acetylcholine-releasing capacity. The transfected N18TG-2 cells expressed Torpedo mediatophore in their plasma membrane. In response to an electrical stimulus, they generated in the myocyte evoked currents that were curare sensitive and calcium dependent and displayed discrete amplitude levels, like in naturally occurring synapses. 相似文献
23.
M. Margaret Prechel Yvonne Lozano Mark A. Wright J. Ihm M. R. I. Young 《Cancer immunology, immunotherapy : CII》1996,42(4):213-220
Lewis lung carcinoma (LLC-LN7) tumors stimulate myelopoiesis and increase the presence of granulocyte/macrophage (GM) progenitor
cells having natural suppressor activity. Treatment of these tumor-bearing mice with interleukin-12 (IL-12) resulted in minimal
immune modulation. The objective of this study was to determine whether eliminating natural suppressor activity would allow
for immune stimulation by IL-12. Treatment of LLC-LN7 tumor-bearing mice with vitamin D3 eliminated natural suppressor activity. In mice that were first treated with vitamin D3 and then also with IL-12, there was stimulation of splenic T cell proliferation in response to immobilized anti-CD3 plus
IL-2. In addition, spleen and lymph node cells from vitamin-D3/IL-12-treated tumor-bearing mice became stimulated in response to autologous tumor to produce interferon γ (IFNγ), although
IL-2 production was not stimulated. A prominent effect of the combined vitamin-D3/IL-12 treatment regimen was the synergistic augmentation of autologous tumor-specific cytolytic activity within the regional
lymph nodes. The generation of these tumor-specific effector cells required the presence of the tumor mass since such activity
was not elicited in the lymph nodes of mice from which the tumors had been surgically excised. The results of this study show
that, after treatment of tumor bearers with vitamin D3 to eliminate GM-suppressor cells, IL-12 can induce select regional antitumor immune responses, particularly IFNγ production
and cytolysis by regional lymph node cells of autologous tumor.
Received: 15 December 1995 / Accepted: 22 March 1996 相似文献
24.
Liver diseases are closely associated with elevated levels of interleukin-8 (IL-8), suggesting the ability to inhibit IL-8 production could enhance the treatment of liver diseases. Paeoniflorin is a major active constituent of dried Paeoniae Radix Alba root (Baishao in Chinese) which is widely used in China to treat liver diseases. We examined the effects and underlying mechanisms of paeoniflorin on IL-8 production in primary human hepatic sinusoidal endothelial cells (HHSECs). Concanavalin A (ConA) at 20 μg/mL produced a 5.2-fold increase in IL-8 mRNA by 8 h, and a 14.2-fold rise in IL-8 levels by 16 h. Inhibition of MEK (ERK kinase) and extracellular signal-regulated kinase (ERK) by PD98059 and U0126, or inhibition of phosphatidylinositol 3-kinase (PI3K) by LY294002 blocked both ConA-induced IL-8 mRNA expression and IL-8 secretion. Paeoniflorin reduced ConA-induced IL-8 mRNA expression and IL-8 release by 57.9% and 52.8%, respectively, and also decreased ConA-stimulated phosphorylation of ERK1/2 and Akt, suggesting paeoniflorin inhibits IL-8 expression and release by inhibiting the ERK1/2 and Akt pathways. Combining paeoniflorin with U0126 or LY294002 at low doses showed supra-additive inhibition of not only phospho-ERK1/2 and phospho-Akt by 46.4% and 35.0%, but also IL-8 release by 42.4% and 36.1% and IL-8 mRNA expression by 43.5% and 31.8%, respectively. In conclusion, paeoniflorin most likely contributes to the therapy for liver disease by exerting anti-inflammatory effects on HHSECs through blocking IL-8 secretion via downregulation of ERK1/2 and Akt phosphorylation. 相似文献
25.
《Bioorganic & medicinal chemistry letters》2014,24(7):1846-1850
Two novel small molecule gonadotropin-releasing hormone (GnRH) receptor antagonists (12 and 13) of the furamide-class were synthesized and evaluated in vitro for their receptor binding affinities for the rat GnRH receptor. Radiolabeling with no carrier added fluorine-18 of the appropriate precursors was investigated in a one-step reaction. Log P (Octanol/PBS pH 7.4) and serum stability of the compounds were investigated. The antagonists showed low nM affinity for the rat GnRH receptor. 18F-radiolabled compounds were obtained in high radiochemical purity (>95%) and specific activity (>75 GBq/μmol). These findings suggest this class of compounds holds promise as potential probes for PET targeting of GnRH-receptor expression. 相似文献
26.
27.
Preterm birth (PTB) is a leading cause of neonatal mortality and morbidity worldwide, and represents a heavy economic and social burden. Despite its broad etiology, PTB has been firmly linked to inflammatory processes. Pro-inflammatory cytokines are produced in gestational tissues in response to stressors and can prematurely induce uterine activation, which precedes the onset of preterm labor. Of all cytokines implicated, interleukin (IL)-1 has been largely studied, revealing a central role in preterm labor. However, currently approved IL-1-targeting therapies have failed to show expected efficacy in pre-clinical studies of preterm labor. Herein, we (a) summarize animal and human studies in which IL-1 or IL-1-targeting therapeutics are implicated with preterm labor, (b) focus on novel IL-1-targeting therapies and diagnostic tests, and (c) develop the case for commercialization and translation means to hasten their development. 相似文献
28.
M. Wolf M. Buchheim E. Hegewald L. Krienitz D. Hepperle 《Plant Systematics and Evolution》2002,230(3-4):161-171
The complete 18S rRNA gene sequences of four Sphaeroplea C.A. Agardh strains (Sphaeropleales, Sphaeropleaceae), two Atractomorpha Hoffman strains (Sphaeropleales, Sphaeropleaceae) and two Ankyra Fott strains (Chlorococcales, Characiaceae) were determined and subjected to phylogenetic analyses. The analyses indicated
that all these taxa belong to a monophyletic lineage (Sphaeropleaceae) and are related to a group of chlorophycean algae comprising
autosporic taxa and taxa that reproduce by zoospores which are characterized by directly opposed basal bodies. The taxonomic
assignment of the Sphaeropleaceae as a family within the Sphaeropleales (Chlorophyta, Chlorophyceae) is discussed.
Received December 22, 2000 Accepted September 25, 2001 相似文献
29.
Michael R. Heaven Anthony W. Herren Daniel L. Flint Natasha L. Pacheco Jiangtao Li Alice Tang Fatima Khan James E. Goldman Brett S. Phinney Michelle L. Olsen 《Molecular & cellular proteomics : MCP》2022,21(1):100180
Alexander disease (AxD) is a rare and fatal neurodegenerative disorder caused by mutations in the gene encoding glial fibrillary acidic protein (GFAP). In this report, a mouse model of AxD (GFAPTg;Gfap+/R236H) was analyzed that contains a heterozygous R236H point mutation in murine Gfap as well as a transgene with a GFAP promoter to overexpress human GFAP. Using label-free quantitative proteomic comparisons of brain tissue from GFAPTg;Gfap+/R236H versus wild-type mice confirmed upregulation of the glutathione metabolism pathway and indicated proteins were elevated in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which had not been reported previously in AxD. Relative protein-level differences were confirmed by a targeted proteomics assay, including proteins related to astrocytes and oligodendrocytes. Of particular interest was the decreased level of the oligodendrocyte protein, 2-hydroxyacylsphingosine 1-beta-galactosyltransferase (Ugt8), since Ugt8-deficient mice exhibit a phenotype similar to GFAPTg;Gfap+/R236H mice (e.g., tremors, ataxia, hind-limb paralysis). In addition, decreased levels of myelin-associated proteins were found in the GFAPTg;Gfap+/R236H mice, consistent with the role of Ugt8 in myelin synthesis. Fabp7 upregulation in GFAPTg;Gfap+/R236H mice was also selected for further investigation due to its uncharacterized association to AxD, critical function in astrocyte proliferation, and functional ability to inhibit the anti-inflammatory PPAR signaling pathway in models of amyotrophic lateral sclerosis (ALS). Within Gfap+ astrocytes, Fabp7 was markedly increased in the hippocampus, a brain region subjected to extensive pathology and chronic reactive gliosis in GFAPTg;Gfap+/R236H mice. Last, to determine whether the findings in GFAPTg;Gfap+/R236H mice are present in the human condition, AxD patient and control samples were analyzed by Western blot, which indicated that Type I AxD patients have a significant fourfold upregulation of FABP7. However, immunohistochemistry analysis showed that UGT8 accumulates in AxD patient subpial brain regions where abundant amounts of Rosenthal fibers are located, which was not observed in the GFAPTg;Gfap+/R236H mice. 相似文献
30.
CHRISTOPHE GONINDARD CATHERINE GOIGOUX ETIENNE HOLLANDE LUCIEN DUSSOURD D'HINTERLAND 《Pigment cell & melanoma research》1996,9(3):148-153
The injection of α-MSH or of one of its analogues ([Nle4-D.Phe7] α-MSH4–10) reduced, in vivo, the release of two cytokines (IL-1α and TNFα) involved in inflammation. The inflammatory state was induced in BALB/c mice by intraperitoneal injection of a sublethal dose of lipopolysaccharides (LPS). The assay of these cytokines by ELISA showed a reduction of 20% with α-MSH and between 30 and 60% with the α-MSH analogue. The α-MSH or the analogue was administered in one of two ways: intravenously or subcutaneously. The most efficient method seemed to be the subcutaneous one because it improved the activity 10,000 times more than the intravenous method. Moreover, the analogue induced a regression of mortality in the animals treated by the intravenous method. Our results show that α-MSH and one of its analogues inhibit IL-1α and TNFα, and can be used as anti-inflammatory molecules. 相似文献