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991.
Natalia Bogdanova Alexandr V. Togo Magdalena Ratajska Wojtek Kluźniak Zalina Takhirova Theresa Tarp Darya Prokofyeva Marina Bermisheva Grigoriy A. Yanus Tatiana V. Gorodnova Anna P. Sokolenko Alina Kuźniacka Amira Podolak Maciej Stukan Dominika Wokołorczyk Jacek Gronwald Danuta Vasilevska Vilius Rudaitis Ingo B. Runnebaum Matthias Dürst Tjoung-Won Park-Simon Peter Hillemanns Natalia Antonenkova Elza Khusnutdinova Janusz Limon Jan Lubinski Cezary Cybulski Evgeny Imyanitov Thilo Dörk 《Familial cancer》2015,14(1):145-149
992.
Wensheng Liu Fei Yue Minhua Zheng Angelica Merlot Dong-Hun Bae Michael Huang Darius Lane Patric Jansson Goldie Yuan Lam Liu Vera Richardson Sumit Sahni Danuta Kalinowski Zaklina Kovacevic Des. R. Richardson 《Oncotarget》2015,6(11):8851-8874
N-myc downstream regulated gene-1 (NDRG1) is a potent metastasis suppressor that plays a key role in regulating signaling pathways involved in mediating cancer cell invasion and migration, including those derived from prostate, colon, etc. However, the mechanisms and molecular targets through which NDRG1 reduces cancer cell invasion and migration, leading to inhibition of cancer metastasis, are not fully elucidated. In this investigation, using NDRG1 over-expression models in three tumor cell-types (namely, DU145, PC3MM and HT29) and also NDRG1 silencing in DU145 and HT29 cells, we reveal that NDRG1 decreases phosphorylation of a key proto-oncogene, cellular Src (c-Src), at a well-characterized activating site (Tyr416). NDRG1-mediated down-regulation of EGFR expression and activation were responsible for the decreased phosphorylation of c-Src (Tyr416). Indeed, NDRG1 prevented recruitment of c-Src to EGFR and c-Src activation. Moreover, NDRG1 suppressed Rac1 activity by modulating phosphorylation of a c-Src downstream effector, p130Cas, and its association with CrkII, which acts as a “molecular switch” to activate Rac1. NDRG1 also affected another signaling molecule involved in modulating Rac1 signaling, c-Abl, which then inhibited CrkII phosphorylation. Silencing NDRG1 increased cell migration relative to the control and inhibition of c-Src signaling using siRNA, or a pharmacological inhibitor (SU6656), prevented this increase. Hence, the role of NDRG1 in decreasing cell migration is, in part, due to its inhibition of c-Src activation. In addition, novel pharmacological agents, which induce NDRG1 expression and are currently under development as anti-metastatic agents, markedly increase NDRG1 and decrease c-Src activation. This study leads to important insights into the mechanism involved in inhibiting metastasis by NDRG1 and how to target these pathways with novel therapeutics. 相似文献
993.
Pawe Lenartowicz Danuta Witkowska Beata yszka-Haberecht Baej Dziuk Krzysztof Ejsmont Jolanta
witek-Kozowska Pawe Kafarski 《RSC advances》2020,10(40):24045
Aminophosphonates are an important group of building blocks in medicinal and pharmaceutical chemistry. Novel representatives of this class of compounds containing nontypical side chains are still needed. The aza-Michael-type addition of amines to phosphonodehydroalanine derivatives provides a simple and effective approach for synthesizing N′-substituted α,β-diaminoethylphosphonates and thus affords general access to aminophosphonates bearing structurally diverse side chains. Thermodynamic analysis of the chosen aminophosphonates at physiological pH proves that they serve as potent chelators for copper(ii) ions and moderate chelators for nickel(ii) ions.A convenient and general reaction is presented for the preparation of diaminophosphonates further evaluated as chelators of metal ions. 相似文献
994.
Jolanta Soltysiak Bogda Skowronska Piotr Fichna Danuta Ostalska-Nowicka Witold Stankiewicz Maria Lewandowska-Stachowiak Katarzyna Lipkowska Jacek Zachwieja 《Pediatric nephrology (Berlin, Germany)》2014,29(12):2373-2378
Background
The aim of this study was to evaluate the association between blood pressure (BP) and urinary angiotensinogen excretion (uAGT) and renal sodium excretion (uNa) in children with type 1 diabetes mellitus (DM1).Methods
The study group consisted of 52 children with DM1 (28 males and 24 females) with albumin/creatinine ratio (ACR) below 30 mg/g and glomerular filtration rate (eGFR) above 90 ml/min/1.73 m2. BP was assessed by 24-h ambulatory blood pressure monitoring (ABPM).Results
The patients showed significantly increased uAGT values with respect to controls (median 0.00 and range 1.76 vs. 0.00 and 0.00 ng/mg, respectively). The significant increase of uAGT was observed even in prehypertensive patients. uAGT concentrations showed positive correlation with systolic and diastolic 24-h BP and with mean arterial pressure (MAP) (r?=?0.594). uNa values were negatively correlated with BP parameters, uAGT, ACR and eGFR.Conclusions
An increase in uAGT precedes hypertension (HTN) in normoalbuminuric children with DM1 and may be considered as a new marker of HTN. Decreased sodium excretion seems to be involved in the development of HTN and early renal injury. Both uAGT and uNa are associated with BP in normoalbuminuric diabetic children. 相似文献995.
Monika Teresa Stomal-Słowińska Beata Daniluk Joanna Trela Jerzy Słowiński Krzysztof Majchrzak Danuta Kądzielowa Henryk Majchrzak 《Neurologia i neurochirurgia polska》2013,47(6):555-563
Background and purposeClassical definitions of aphasia describe deficits of different language levels (syntactic, semantic, phonologic) hindering the ability to communicate. Recent studies indicate, however, that impairment of particular aspects of linguistic competencies in aphasia differs in severity. Contemporary approach to the aphasic symptoms presents them as disturbed access of linguistic representations to the awareness system. Accordingly, such an approach requires different types of tasks: direct, involving explicit language processes, and indirect, based on implicit language representations. The aim of our study was to examine explicit and implicit language processes in patients with aphasia after resection of the tumour of left cerebral hemisphere along with characterization of relationships between explicit and implicit language processes.Material and methodsOur cohort included 28 right-handed patients who were divided into four equal groups: two clinical (brain tumours) and two control (lumbar disc disease). Four tasks that assess and compare language processes: lexical decisions (at explicit and implicit levels), sorting of picture captions and word monitoring were implemented.ResultsIn direct tasks, patients with aphasia provided less correct lexical decisions at word level, but did not show deficits in sentence comprehension. In both groups, no priming effect was observed in tasks requiring implicit lexical decisions. The longest time was found in non-primed words, the shortest in pseudowords. The differences between groups regarding word monitoring were also observed. Patients with aphasia obtained longer reaction times in all types of sentences (of different grade of language correctness), with respect to low- and high- frequency words.ConclusionsPatients with aphasia after brain tumour resection show more pronounced impairments of explicit than implicit linguistic behavior; the same effect was found in studies on forgetting in amnestic syndrome. 相似文献
996.
Danuta Kowalczyk-Pachel Grażyna Chwatko Małgorzata Iciek Joanna Czyżyk Małgorzata Filip Lidia Włodek Elżbieta Lorenc-Koci 《Neurotoxicity research》2013,24(3):377-392
The aim of the present studies was to evaluate cocaine-induced changes in the concentrations of different redox forms of cysteine (Cys) and homocysteine (Hcy), and products of anaerobic Cys metabolism, i.e., labile, reduced sulfur (LS) in the rat plasma. The above-mentioned parameters were determined after i.p. acute and subchronic cocaine treatment as well as following i.v. cocaine self-administration using the yoked procedure. Additionally, Cys, Hcy, and LS levels were measured during the 10-day extinction training in rats that underwent i.v. cocaine administration. Acute i.p. cocaine treatment increased the total and protein-bound Hcy contents, decreased LS, and did not change the concentrations of Cys fractions in the rat plasma. In turn, subchronic i.p. cocaine administration significantly increased free Hcy and lowered the total and protein-bound Cys concentrations while LS level was unchanged. Cocaine self-administration enhanced the total and protein-bound Hcy levels, decreased LS content, and did not affect the Cys fractions. On the other hand, yoked cocaine infusions did not alter the concentration of Hcy fractions while decreased the total and protein-bound Cys and LS content. This extinction training resulted in the lack of changes in the examined parameters in rats with a history of cocaine self-administration while in the yoked cocaine group an increase in the plasma free Cys fraction and LS was seen. Our results demonstrate for the first time that cocaine does evoke significant changes in homeostasis of thiol amino acids Cys and Hcy, and in some products of anaerobic Cys metabolism, which are dependent on the way of cocaine administration. 相似文献
997.
998.
Tomasz Pizo Marek Rajzer Wiktoria Wojciechowska Tomasz Drod Dorota Drod Marta Rojek Krystian Gruszka Danuta Czarnecka 《Archives of Medical Science》2021,17(1):9
IntroductionThe aim of this study was to assess the relations between plasma renin activity (PRA), serum aldosterone concentration (ALDO) and selected asymptomatic organ damage (AOD) indices in mild primary arterial hypertension (AH).Material and methodsWe measured PRA, ALDO, and selected AOD indices (carotid-femoral pulse wave velocity (cfPWV), central aortic pulse pressure (cPP), estimated glomerular filtration rate (eGFR)) in 122 patients with untreated AH.ResultsPatients with high PRA (≥ 0.65 ng/ml/h) were characterized by lower plasma sodium and aldosterone to renin ratio (ARR), higher ALDO, but a similar level of AOD indices compared to patients with low PRA. cfPWV (p = 0.04) and cPP (p = 0.019) increased with ARR, while eGFR decreased with ALDO (p = 0.008). Only eGFR was independently correlated with ALDO. In subjects with simultaneously high PRA and ARR values, we found significantly higher cfPWV (p = 0.02) and cPP (p = 0.04) and lower eGFR (p = 0.02) than in those with high PRA but low ARR values.ConclusionsAssessment of the influence of the renin-angiotensin-aldosterone system (RAAS) on AOD should include the relationship between renin and aldosterone. The PRA itself has no predictive value for AOD. More advanced arterial stiffness and renal impairment are associated with increased PRA and ARR. The RAAS activity might be useful in AOD prediction and hypertension severity assessment. 相似文献
999.
Bailey-Downs LC Mitschelen M Sosnowska D Toth P Pinto JT Ballabh P Valcarcel-Ares MN Farley J Koller A Henthorn JC Bass C Sonntag WE Ungvari Z Csiszar A 《The journals of gerontology. Series A, Biological sciences and medical sciences》2012,67(4):313-329
Recent studies demonstrate that age-related dysfunction of NF-E2-related factor-2 (Nrf2)-driven pathways impairs cellular redox homeostasis, exacerbating age-related cellular oxidative stress and increasing sensitivity of aged vessels to oxidative stress-induced cellular damage. Circulating levels of insulin-like growth factor (IGF)-1 decline during aging, which significantly increases the risk for cardiovascular diseases in humans. To test the hypothesis that adult-onset IGF-1 deficiency impairs Nrf2-driven pathways in the vasculature, we utilized a novel mouse model with a liver-specific adeno-associated viral knockdown of the Igf1 gene using Cre-lox technology (Igf1(f/f) + MUP-iCre-AAV8), which exhibits a significant decrease in circulating IGF-1 levels (~50%). In the aortas of IGF-1-deficient mice, there was a trend for decreased expression of Nrf2 and the Nrf2 target genes GCLC, NQO1 and HMOX1. In cultured aorta segments of IGF-1-deficient mice treated with oxidative stressors (high glucose, oxidized low-density lipoprotein, and H(2)O(2)), induction of Nrf2-driven genes was significantly attenuated as compared with control vessels, which was associated with an exacerbation of endothelial dysfunction, increased oxidative stress, and apoptosis, mimicking the aging phenotype. In conclusion, endocrine IGF-1 deficiency is associated with dysregulation of Nrf2-dependent antioxidant responses in the vasculature, which likely promotes an adverse vascular phenotype under pathophysiological conditions associated with oxidative stress (eg, diabetes mellitus, hypertension) and results in accelerated vascular impairments in aging. 相似文献
1000.