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61.
Safety of injectable autologous human fibroblasts 总被引:3,自引:0,他引:3
Keller G Sebastian J Lacombe U Toft K Lask G Revazova E 《Bulletin of experimental biology and medicine》2000,130(8):786-789
Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients
aged 37–61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant
sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that
cultured fibroblasts were functionally active and produced large quantities of type I collagen.In vitro studies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction
capacity.In vivo experiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 203–206, August, 2000 相似文献
62.
Andrew D. Medhurst Gerd E. K. Novotny Stephen G. Parker Nicola M. Deighton Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(3):257-265
Summary To investigate whether 5-HT1-like receptor-mediated inhibition of adenosine 3 : 5-cyclic monophosphate (cyclic AMP) accumulation occurs in nerves or smooth muscle of saphenous vein, infusions of 6-hydroxydopamine (6-OHDA) were administered to dogs with the aim of inducing sympathetic nerve damage. The effects of 6-OHDA on other 5-HT1-like receptor-mediated responses at the pre- and post-junctional level were investigated for comparison by studying 5-hydroxytryptamine (5-HT)-induced inhibition of 3H-noradrenaline release and contraction of smooth muscle respectively.Disruption of nerve function by 6-OHDA was revealed by the lack of catecholaminergic fluorescence and neurogenic contractile responses in saphenous veins from dogs treated with 6-OHDA. In addition, severe impairment of neuronal uptake mechanisms were apparent since basal efflux of 3H-noradrenaline, electrically-evoked release of 3H-noradrenaline and remaining 3H-noradrenaline content were considerably reduced. Some 3H-noradrenaline was taken up and released in 6-OHDA treated tissues which is consistent with the existence of nerve varicosities resistant to the present dosing regime of 6-OHDA, an observation substantiated by electron microscopy studies showing inconsistent lesions of nerve terminals.6-OHDA pre-treatment potentiated the smooth muscle contractile responses mediated by 5-HT1-like receptors as well as potentiating 5-HT-evoked inhibition of prostaglandin E2-stimulated cyclic AMP accumulation. It did not, however, affect 5-HT-induced inhibition of 3H-noradrenaline release. The present results suggest that inhibition of cyclic AMP accumulation by 5-HT occurs predominantly in smooth muscle.
Correspondence to A. J. Kaumann at the above address 相似文献
63.
I. T. Bognar M. T. Wesner H. Fuder 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(1-2):22-29
Summary The potencies of several muscarine receptor antagonists in blocking either the autoinhibition of acetylcholine release or the muscarinic contraction of the sphincter muscle upon acetylcholine release were investigated in the guinea-pig iris. The agonist at pre- or postjunctional muscarine receptors was acetylcholine released upon field stimulation (5.5 Hz, 2 min) of the irides preloaded with 14C-choline. The stimulation-evoked 14C-overflow was doubled in the presence of atropine 0.1 mol/l but unaffected by the agonist (±)-methacholine (50 mol/l). Thus, under the present stimulation conditions, the autoinhibition of acetylcholine release on the guinea-pig iris cholinergic nerves was nearly maximally activated. Isotonic contractions of the irides upon field stimulation consisted of a rapid, atropine (0.1 mol/l). peak phase followed by a sustained contraction which involved a cholinergic and a non-cholinergic stimulation of the sphincter muscle. The M2-selective antagonists methoctramine (10 mol/l) and gallamine (100 µmol/l). increased both the 14Goverflow and the peak contractions evoked by field stimulation. In contrast, the M3-selective antagonist hexahydrosiladifenidol (0.1–10 mol/l) failed to affect the evoked 14C-release but concentration-dependently (1–10 mol/l) reduced the iris contractions. Pirenzepine (10 mol/l) enhanced the evoked 14C-overflow and inhibited the peak contractions (0.1–10 mol/l; maximal effect at 10 mol/l). The low potency of the antagonist at both receptor sites indicates that an M1 muscarine receptor is not involved. The results are consistent with the idea of M2 muscarine receptors mediating autoinhibition of acetylcholine release in the guinea-pig iris and M3-like receptors inducing the contraction of the sphincter muscle.
Send offprint requests to I. T. Bognar at the above address 相似文献
64.
四乙基胺抑制蟾酥的强心效应 总被引:1,自引:0,他引:1
[目的]观察蟾酥对离体蟾蜍心脏收缩运动的影响和各种受体阻断剂、钾通道阻断剂对这种效应的影响。[方法]将离体蟾蜍心脏收缩运动用张力换能器转换成电信号,通过Doctor-95 Super Lab软件系统在电脑上连续记录心率和收缩力的变化,并打印成曲线。[结果]取自蟾蜍同体耳后腺的蟾酥对离体蟾蜍心脏收缩运动有增强作用。M受体阻断剂阿托品(0.5g/L)和β受体阻断剂心得安(0.01g/L)不能阻断蟾酥对离体蟾蜍心脏收缩运动的增强作用,而α受体阻断剂酚妥拉明(0.5g/L)、非选择性钾通道阻断剂四乙基胺(10mmol/L)则明显抑制蟾酥对离体蟾蜍心脏收缩运动的增强作用。[结论]蟾酥是通过α受体作用于钾通道而增强离体蟾蜍心脏收缩运动。 相似文献
65.
Effects of benactyzine on action potentials and contractile force of guinea pig papillary muscles 总被引:1,自引:0,他引:1
DING Zhongren )△ ZHANG Yan ) ZHANG Guiqing ) KE Jun ) HU Xiangjie ) )Department of Hematology Peking Union Medical Hospital Chinese Academy of Medical Sciences Beijing )Department of Pharmacology Henan Medica 《郑州大学学报(医学版)》2000,35(2)
INTRODUCTIONBenactyzineisasyntheticblockerofM receptorpos sessingsmoothmusclerelaxantpropertiesandquinidine likeactiononheart[1] .Benactyzineiseffectiveinrestor ingcirculatoryfunctiondisturbedbyorganophosphatepoi soning[2 ,3] .Previousstudiessuggestedthatbena… 相似文献
66.
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69.
不同浓度乙醇灌流液对蟾蜍离体心脏活动影响的比较分析 总被引:5,自引:1,他引:4
用不同浓度乙醇灌流液灌流蟾蜍离体心脏,观察其对离体心脏心率、心肌收缩力和心输出量的变化。结果显示:心率减慢,但在10 m mol/L 稍有加快( P > 0 .05) ,浓度在20 m m ol/L 以上时减慢才明显( P < 0 .05) ;心肌收缩幅度下降,其表现浓度越大下降越明显( P < 0 .05 ~0 .01) ;心输出量在10 m mol/L、15 m mol/L 时略有增加,超过30 m mol/L 以后心输出量下降,但不明显( P > 0 .05) 。表明乙醇过量有减慢心率和抑制心肌收缩力的作用,而对输出量影响不大。 相似文献
70.
OTSUJI Y.; TODA H.; KISANUKI A.; KOYANO T.; KUROIWA R.; MURAYAMA T.; MATSUSHITA R.; NAKAO S.; TOMARI T.; TANAKA H. 《European heart journal》1994,15(4):462-467
We investigated whether the left ventricular filling profile,defined as the early to late diastolic left ventricular fillingvolume ratio, during the preceding control beats actually affectsthe pulse pressure during a ventricular premature contraction(PVC). Twenty patients underwent invasive electrophysiologicalstudy for sinus bradycardia. VPCs with various coupling intervalswere induced by right ventricular electrical stimulation, andthe mitral filling flow velocity pulsed Doppler echocardiography,the femoral arterial pressure curve and the electrocardiogramwere simultaneously recorded The early to late diastolic velocity-rimeintegral ratio (E1/A1 ratio) of the mitral filling flow velocityduring the control beats which preceded the VPC was measuredas an index characterizing left ventricular filling profile.The coupling interval of each VPC and the extrasystolic beatpulse pressure were measured The ratio of the extrasystolicbeat pulse pressure to the control beat pulse pressure was expressedin % (% extrasystolic beat pulse pressure). The correlationbetween the coupling interval and the % extrasystolic beat pulsepressure was investigated. Coupling intervals of 0·80,0·70, 0·60, 0·50, and 0·45 s wereused At a coupling interval of 0·80 or 0·45 s,the % extrasystolic beat pulse pressure showed no significantcorrelation with the E1/A1 ratio. In contrast, the % extrasystolicbeat pulse pressure with coupling intervals of 0·70,0·60, and 0·50 s showed a significant positivecorrelation with the E1/A1 ratio (r=0·67, 0·74,and 0·66 P<0·01, respectively). In additionto the prematurity and the site of origin of the VPCs, the leftventricular filling profile during the preceding control beatsmay significantly affect the height of the pulse pressure duringextrasystoles with medium length coupling intervals. 相似文献