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81.
营养缺乏及补充维生素A对大鼠肺巨噬细胞功能的影响 总被引:2,自引:0,他引:2
采用Wistar大鼠,从怀孕16天进行限食喂养直到生后45天,干预组从生后第36天及第42天分别给予维生素A灌胃,每次2000IU。结果表明,补充维生素A可明显增加大鼠的胸腺重量、肺巨噬细胞的数目、巨噬细胞的吞噬功能及NO-2的分泌。维生素A可部分纠正营养缺乏导致的免疫缺陷、胸腺萎缩,活化肺巨噬细胞功能,其作用机制有待于进一步研究。 相似文献
82.
Fokko Bosker Dorien Vrinten André Klompmakers H. Westenberg 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(3):347-353
The modulation of extracellular 5-hydroxytryptamine (5-HT) in the central nucleus of the amygdala (CeA) by 5-HT1A receptors was studied by intracerebral microdialysis in awake and freely moving rats. Local administration of 1 μM tetrodotoxin
(TTX), 60 mM K+ and perfusion with Ca2+-free Ringer containing EGTA confirmed that the major part of dialysate 5-HT levels from the CeA is of neuronal origin. Administration
of 300 nM of RU 24969, a 5-HT1B receptor agonist, through the probe into the CeA decreased dialysate 5-HT levels to 67.2% of the baseline value. Systemic
administration of the 5-HT1A receptor agonists 8-OH-DPAT and flesinoxan dose-dependently decreased 5-HT levels in the CeA. The effect of 0.3 mg/kg of
flesinoxan could be completely antagonized by systemic administration of 0.05 mg/kg WAY 100635, a 5-HT1A receptor antagonist. WAY 100635 alone had only minimal effects at this dose. These data show that a major part of the extracellular
5-HT in the CeA stems from 5-HT neurons and that the amount of 5-HT released into this brain region can be modulated by 5-HT1A receptors.
Received: 11 September 1996 / Accepted: 25 November 1996 相似文献
84.
Akira Horiuchi Robin A Felder† 《Clinical and experimental pharmacology & physiology》1996,23(S3):150-154
1. In orefer to develop a simple, efficient system for the highlvel expression of dopamine recetors in eukaryotic cells, we have studied the effects of n-butyrate on the expression of rat D1A dopamine receptor cDNA in mouse fibroblast LTK- cells as compared with those of n-butyrate on endogenous D1 receptor levles in opossum kidney cells.
2. In the transfected LTK- cell mebranes with pRc/CMVD1A receptor cDNA, a selective D1 dopamine antagonist, [3 H]-SCH 23390, exhibited a Kd of 0.9 ± 0.1 nmol/L and a Bmax of 0.35 ± 0.05 pmol/mg protien (n = 5).
3. Addtion of n-butrate (2–10 mmol/L) to the culture medium for 48h dose-dependently increased the D1A receptor level up to 1.5 ± 0.3 pmol/mg protien (n = 7), although the Kd values were not affected. The increase in receptor level was accompanined by an elevation of selective D1 agoinist-induced adenyly cyclase activity.
4. In contrast, n-butyrate treatment (2–10 mmol/L) did not affect either endogenous D1 receptor levels or fendoldopmainduced adenylyl cyclase activity in possum kidney cells.
5. These results sugges n-butyrate is a sueful tool for obtaining high-level expression of D1A dopamine receptor cDNA in mouse fibroblast LTK- cells. 相似文献
2. In the transfected LTK- cell mebranes with pRc/CMVD
3. Addtion of n-butrate (2–10 mmol/L) to the culture medium for 48h dose-dependently increased the D
4. In contrast, n-butyrate treatment (2–10 mmol/L) did not affect either endogenous D
5. These results sugges n-butyrate is a sueful tool for obtaining high-level expression of D
85.
采集450例战士血清标本,分别用国家代表株甲3/济防/15/90(H3N2)和甲3/北京/32/92(H3N2)作血清血凝抑制抗体测定,青年对甲3型抗体阳性率为60%~67%,其GMT为34~45。1994~1995年两年中在军营人群中分离到3株H3N2毒株流行株,分别应用国际、国家和地方代表株作抗原性分析,证明流行株与它们之间抗原性有明显差异。本文分离到的3株流行株均上送国家流感中心鉴定,证实为H3N2亚型毒株。 相似文献
86.
W. Couet B. Istin P. Seniuta D. Morel L. Potaux J. B. Fourtillan 《European journal of clinical pharmacology》1990,39(2):165-167
Summary The influence of treatment with ponsinomycin, a new macrolide antibiotic, on the pharmacokinetics of cyclosporin A has been studied in 10 renal transplant patients. The pharmacokinetics of cyclosporin A was investigated at steady state, before and during treatment with ponsinomycin.On average, the blood levels of cyclosporin A were doubled by the macrolide, possibly due to a decrease in elimination or/and to an increase in absorption.Ponsinomycin should be use very carefully in patients treated with cyclosporin A. 相似文献
87.
A. J. Varghese V. N. Chaturvedi 《Indian journal of otolaryngology and head and neck surgery》2007,59(3):233-236
Objective To find out the usability and advantage with regard to the advent of new and more costly antibiotics. In the treatment of
Peritonsillar abscess the demonstration of, both aerobic and anaerobic organisms has raised the question of possible need
to treat with antibiotics effective against anaerobes.
It was in this very context that this study was planned to find out if we still have an economically and easily available
antibiotic to treat Peritonsillar abscess.
Conclusions Injectable penicillin is the drug of choice in PTA as GABHS and staphylococcus aureus coagulase positive are the most common
organism associated with this condition. Even where penicillin resistant organism is present, effective management of the
abscess is possible if it is drained well and weak hydrogen peroxide gargles are used along with injectable penicillin. 相似文献
88.
D. M. Jackson C. E. Wallsten E. Jerning P.-S. Hu A. M. Deveney 《Psychopharmacology》1998,139(4):300-310
The aim was to study firstly, the motor effects of a new 5-HT1A antagonist, NDL-249 [(R)-3-(N-cyclopentyl-N-propylamino)-8-fluoro-3,4-dihydro-2H-1-benzopyran-5-carboxamide hydrochloride] and of the reference 5-HT1A antagonist WAY-100 635 [N-(2-(1-(4-(2-methoxyphenyl)piperazinyl))ethyl)-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride], in comparison to the 5-HT1A agonist (±)-8-OH-DPAT [(8-hydroxy-2-(di-N-propylamino) tetralin, hereafter 8-OH-DPAT], in rats acclimatised to the automated activity cages; secondly, to study whether
the behavioural effects of NDL-249 and 8-OH-DPAT are sensitive to the 5-HT depleting effects of p-chlorophenylalanine (PCPA); thirdly, to characterise the nature of the antagonist-induced activation seen in the automatic
activity cages with the aid of a behavioural observation analysis; fourthly, to examine the interaction between the 5-HT1Areceptors mediating the behavioural effects and dopamine (DA) receptors. NDL-249 was found to bind in vitro to rat hippocampal
5-HT1A receptors with high affinity and selectivity. In second messenger studies, it was devoid of agonist-like effects. In the
locomotor activity studies, each antagonist significantly increased the incidence of horizontal activity, peripheral activity
and rearing. 8-OH-DPAT, while significantly increasing peripheral and horizontal activities, decreased the incidence of rearing.
PCPA blocked the motor effects of NDL-249 but did not affect those of 8-OH-DPAT. Observational analyses indicated that NDL-249
induced significant increases at one or more doses in sniffing, rearing and locomotion together with a significant reduction
in stillness. WAY-100 635 significantly increased the incidence of rearing, intense grooming and vacuous chewing. The significant
increases in sniffing, grooming and intense grooming and the significant decrease in stillness induced by the DA D1 agonist, SK&F 38393 [(±)-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrochloride], were not altered by concomitant
pre-treatment with NDL-249. Pre-treatment of rats with either the DA D1 antagonist SCH-23390 (2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol) or the DA D2 antagonist, raclopride, blocked the reduced stillness and increased sniffing and rearing induced by NDL-249. In conclusion,
5-HT1A antagonists including the new selective antagonist, NDL-249, induce mild behavioural activation in rats, which is mediated
probably indirectly via DA systems.
Received: 3 April 1997/Final version: 23 February 1998 相似文献
89.
Vendeville B.; Baran D.; Gascon-Barre M.; Rubin E.; Luu T.; Vallieres S. 《Nephrology, dialysis, transplantation》1995,10(11):2020-2026
BACKGROUND.: Mercuric chloride (HgCl2 induces a lymphoproliferative disorderand autoimmune glomerulonephritis in Brown Norway (BN) rats.This syndrome is the consequence of T cell-dependent polyclonalB cell activation and autoantibody production. We have previouslyshown that HgCl2-induced autoimmune perturbations can be preventedin BN rats by the administration of cyclosporin A (CsA). Themost potent vitamin D3 metabolite 1,25(OH)2 D3 (Vit D3) sharescertain immunomodulatory properties with CsA. We therefore choseto compare the effects of Vit D3 to those of CsA in BN ratstreated with HgCl2 in order to establish whether Vit D3 eitheralone or in combination with CsA can attenuate an autoimmunesyndrome in vivo. METHODS.: BN rats were treated with HgCl2 according to a standard protocol.Subgroups of rats were also given CsA alone, Vit D3 or syntheticanalogues of Vit D3 alone, or combinations of both agents. Differentdoses and routes of administration were compared. The followingmarkers of disease activity were evaluated: mortality, peakproteinuria, serum IgE concentrations, and renal immunoglobulindeposition. RESULTS.: Disease activity was markedly attenuated in all rats treatedwith CsA alone. Vit D3 and certain of its synthetic analoguesadministered alone also tempered the autoimmune process, butto a lesser extent than did CsA. The effect of CsA alone wasso potent, that no additive or synergistic effects could bedemonstrated when CsA was administered in combination with VitD3. CONCLUSIONS.: Despite similar described immunomodulatory effects in vitro,CsA is clearly more effective than Vit D3 in preventing HgCl2autoimmune disease in BN rats. This suggests that there is adifference in the cellular targets of these two agents in vivo,and/or a difference in the potency with which HgCl2-triggeredimmune activation is suppressed. 相似文献
90.
CYP1A2 activity, gender and smoking, as variables influencing the toxicity of caffeine 总被引:2,自引:2,他引:0
We have investigated several factors that might be related to the occurrence of toxic effects during the performance of a urinary test with caffeine (300 mg p.o), in 120 healthy volunteers. A total of 218 toxic effects were self-reported by eighty-two (68%) subjects. Females and nonsmokers were at the highest risk (chi-square test, P =0.01). Furthermore, two nonsmoking females experienced a symptomatology with delirium, restlessness, muscle tremor, vomiting and wakefulness. Among females and nonsmokers, those subjects who experienced toxic effects had lower caffeine N3-demethylation index (CYP1A2 activity) compared with unaffected females (1.87±0.51 vs 1.47±0.27, P <0.0005) and nonsmokers (1.69±0.23 vs 1.49±0.31, P <0.02). Caffeine N1- and N7-demethylations indices were also lower among females ( P <0.0005) and nonsmokers ( P <0.02) who reported toxic symptoms. We conclude that CYP1A2 activity, gender and smoking are variables to be considered as influencing the toxicity of caffeine. 相似文献