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71.
目的 :探讨血栓闭塞性脉管炎患者血栓素B2 、前列环素与血液流变学指标的变化及其与发病机制的关系。方法 :用放射免疫法测定TXA2 和PGI2 的代谢产物血栓素B2 (TXB2 )、6 酮 前列腺素F1α( 6 K PGF1α) ,LBY N6A自清洗旋转式粘度计测定血液流变学指标 ,并与对照组对比分析。结果 :血栓闭塞性脉管炎患者TXB2 ( 53.59± 83.2 1ng/L)、6 K PGF1α( 14 .50± 3.4 5ng/L) ,与对照组相比差异显著 ;全血高切粘度、低切粘度、血浆粘度及纤维蛋白原疾病组均高于对照组 ,差异具有统计学意义。结论 :血栓闭塞性脉管炎患者存在TXA2 /PGI2失衡 ,并与血液流变学的改变有密切关系  相似文献   
72.
Summary The 2A-adrenoceptors in rat spleen, kidney, spinal cord and cerebral cortex were studied using [3H]-RX821002 radioligand binding. In the spleen, spinal cord and cerebral cortex, the ligand bound to saturable sites with a K d of about 1 nmol/l and capacities of 134, 240 and 290 fmol/mg protein, respectively. Computer modelling competition curves for 39 drugs, including those for 2A-, 2B- or 2C-adrenoceptor selective drugs, indicated that the sites labelled by [3H]-RX821002 in the spleen consisted of a single population of 2A-adrenoceptors. However, the competition curves for guanoxabenz were definitely biphasic and resolved into two site fits, indicating that guanoxabenz was binding to both high affinity (K d = 35 nmol/1) and low affinity (K d = 8900 nmol/1) 2A-adrenoceptor sites in the proportions 57% and 43%, respectively. The K d Sfor a number of 2-adrenoceptor subtype selective drugs, measured in competition with [3H]-RX821002 in cerebral cortex and spinal cord, were highly correlated with those obtained in the spleen indicating their 2A-adrenoceptor nature. However, by contrast to the results with the spleen, the guanoxabenz competition curves for the spinal cord and cerebral cortex were monophasic and resolved only into one site fits, the K d of guanoxabenz being about 4000 nmol/l for both tissues. Drug K d Sfor kidney 2A-adrenoceptors were also determined using [3H]-RX821002. For nearly all drugs tested, the K d Swere highly correlated with those found for the 2A-adrenoceptors in the other rat tissues. However, for guanoxabenz, the data indicated that it competed with [3H]-RX821002 at a single 2A-adrenoceptor site with a K d of 39 nmol/1. When the rat 2A-adrenoceptor gene RG20 was transiently expressed in COS-7 cells and its ligand binding properties probed using [3H]-RX821002, the drug K d Sobtained were also highly correlated with those found for the 2A-adrenoceptors in the spleen, cerebral cortex, spinal cord and kidney of the rat. For the RG20 encoded receptor, the guanoxabenz competition curves were steep and monophasic and modelled best into one site fits, with the Kd of guanoxabenz being 5200 nmol/1.It is suggested that guanoxabenz can differentiate between two forms of 2A-adrenoceptors in the rat: 2A1 and 2A2. The 2A1-form is present in the spleen and kidney where it shows a high apparent affinity for guanoxabenz. The 2A2-form shows a low apparent affinity for guanoxabenz and is present in the spleen, cerebal cortex and spinal cord. The 2A2-form of the rat 2-adrenoceptor appears to be encoded by the RG20 gene. The 2A, and 2A2-adrenoceptor forms do not represent high and low affinity receptor forms for agonists because assays included EDTA, Gpp(NH)p and Na+, which eliminated the high affinity receptors for agonists.  相似文献   
73.
Summary The regional distribution and the pharmacology of the binding sites labelled with the novel 5-hydroxytryptamine (serotonin) 5-HT1B/1D selective radioligand serotonin-O-carboxy-methyl-glycyl-[125I]tyrosinamide (abbreviated [125I]GTI for the sake of simplicity) was determined using quantitative autoradiography in rat brain. The distribution of [125I]GTI binding sites was largely comparable to that of [125I] iodocyanopindolol ([125I] ICYP) which labels 5-HT1B binding sites (in the presence of 8-OH-DPAT (8-hydroxy-[2N-dipropylamino]tetralin) and isoprenaline, to prevent binding to 5-HT1A and -adrenoceptor binding sites), although a detailed analysis revealed differences.The pharmacology of the [125I]GTI binding sites was analysed using compounds known to display high affinity for and/or distinguish between 5-HT1B and 5-HT1D sites: 5-carboxamidotryptamine (5-CT), sumatriptan, CP 93129 (5-hydroxy-3(4-1,2,5,6-tetrahydropyridyl)-4-azaindole), (–)pindolol, PAPP (4[2-[4-[3-(trifluoromethyl)phenyl]-1-piperazinyl]ethyl] benzeneamine), rauwolscine, and 8-OH-DPAT. The displacement of [125I]GTI by 5-CT was monophasic. By contrast, the selective 5-HT1B compound CP 93129 and (–)pindolol produced biphasic curves showing a majority of high affinity sites in the globus pallidus and the substantia nigra, whereas PAPP and sumatriptan (which are somewhat 5-HT1D selective) produced biphasic curves indicating a minority of high affinity sites in these areas. In addition, by blocking the 5-HT1B sites with 100 nM CP 93129, the remaining population of [125I]GTI binding sites could be studied and was found to have high affinity for PAPP, rauwolscine and 8-OH-DPAT. The pharmacological profile of the major binding component was typical of the 5-HT1B type: 5-CT > CP 93129 (–)pindolol > sumatriptan >/ PAPP > rauwolscine. The profile of the minor component of [125I] GTI binding is best characterised as that of a 5-HTID site: 5-CT > PAPP sumatriptan > rauwolscine > (–)pindolol CP 93129.The localisation of the non 5-HT1B [125I]GTI binding sites was characterised by blocking the 5-HT1B receptors with 100 nM CP 93129. Low densities of the 5-HT1D recognition sites were found to be present in globus pallidus, ventral pallidum, caudate-putamen, subthalamic nucleus, entopeduncular nucleus, substantia nigra (reticular part), nuclei of the (normal and accessory) optic tract, different nuclei of the geniculate body and frontoparietal cortex, although higher densities of 5-HT1B sites were always observed in the same structures. Thus, in agreement with the recent cloning of a rat 5-HT1D receptor cDNA, the presence and the distribution of 5-HT1D sites could be documented in rat brain. However, when compared to 5-HT1B sites, 5-HT1D sites represent only a minor component of the [125I]GTI binding in the rat brain structures studied.Correspondence to: D. Hoyer at the above address  相似文献   
74.
Summary Electrically-evoked release of [3H]acetylcholine from autonomic neurons (myenteric plexus), motoneurons (phrenic nerve) and the central nevous system (neocortex) was investigated in the presence and absence of the calcium channel antagonists -conotoxin GVIA, nifedipine and verapamil, whereby the same species (rat) was used in all experiments. Release of [3H]acetylcholine was measured after incubation of the tissue with [3H]choline.-Conotoxin GVIA markedly reduced (70%) the evoked release of [3H]acetylcholine from the myenteric plexus of the small intestine (IC50: 0.7 nmol/l) with a similar potency at 3 and 10 Hz stimulation. An increase in the extracellular calcium concentration attenuated the inhibitory effect of -conotoxin GVIA. Release of [3H]acetylcholine from the rat neocortex was also inhibited (90%) by -conotoxin GVIA, but the potency was 19-fold lower (IC50: 13 nmol/l). However, the release of [3H]acetylcholine from the phrenic nerve was not reduced by -conotoxin GVIA (100 nmol/l) at 1.8 mmol/l calcium (normal concentration), whereas -conotoxin GVIA inhibited evoked [3H]acetylcholine release by 47% at 0.9 mmol/l calcium. Neither nifedipine (0.1 and 1 mol/l) nor verapamil (0.1, 1 and 10 mol/l) modified the evoked release of [3H]acetylcholine from the myenteric plexus and the phrenic nerve.Acetylcholine release from different neurons appears to be regulated by different types of calcium channels. N-type channels play the dominant role in regulating acetylcholine release from both the myenteric plexus and the neocortex, whereas acetylcholine release from motor nerves is regulated by calcium channel(s) not yet characterized. Send offprint requests to I. Wessler at the above address  相似文献   
75.
Summary To investigate presynaptic, regulatory mechanisms on parasympathetic nerve fibres innervating the airways, the release of newly-synthesized [3H]acetylcholine from the isolated trachea was studied. Reverse phase HPLC followed by liquid scintillation spectrometry was used to separate and quantify the radioactive compounds choline, phosphorylcholine and acetylcholine in the incubation medium and the tissue.During the incubation of the tracheae with [3H]choline a significant synthesis of [3H]acetylcholine (35,000 dpm/preparation) and [3H]phosphorylcholine (500,000 dpm/preparation) occurred. In epithelium-deficient tracheae the formation of [3H]phosphorylcholine was enhanced, whereas the content of [3H]acetylcholine remained unchanged. The spontaneous outflow of tritium consisted mainly of [3H]phosphorylcholine (900 dpm/3 min) and [3H]choline (800 dpm/3 min); [3H]acetylcholine was only a minor fraction (50 dpm/3 min). Electrical stimulation of tracheae with intact epithelium caused only a small release of [3H]acetylcholine (460 dpm in the sample obtained during stimulation), but a considerable outflow of [3H]phosphorylcholine (1,900 dpm) without affecting the outflow of [3H]choline. Electrical stimulation of epithelium-deficient tracheae, however, induced a substantial release of [3H]acetylcholine (2,400 dpm), but only a small outflow of [3H]phosphorylcholine. Chemical stimulation (30 mol/1 veratridine) also caused a large release of [3H]acetylcholine (1,700 dpm) without affecting the outflow of [3H]phosphorylcholine or [3H]choline. Indomethacin (3 mol/1) enhanced the electrically-evoked release of [3H]acetylcholine from tracheae with intact epithelium by 89%.The present experiments demonstrate a strong inhibition by the epithelium of the electrically-evoked release of [3H]acetylcholine from the isolated guinea-pig trachea. Cyclooxygenase products of arachidonic acid do not appear as the main mediators of the epithelium-derived inhibition of acetylcholine release. Send offprint requests to I. Wessler at the above address  相似文献   
76.
Several experiments were conducted to study the effects of the noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, on learning and memory in the rat. Rats displayed impaired performance on several sensorimotor tests and appeared grossly intoxicated when treated IP with 0.2 mg/kg MK-801, but not when treated with lower doses (0.05 or 0.1 mg/kg). Postacquisition performance on two spatial learning tasks involving working memory protocols (reinforced alternation and radial arm maze) was impaired by MK-801 at intoxicating doses (0.2 mg/kg) but not at lower doses (0.05 or 0.1 mg/kg). Using a position habit reversal task, we found that rats could learn to reverse a position habit while under the influence of a nonintoxicating dose of MK-801 (0.1 mg/kg), but when tested on the following day performed as if they did not recall what they had learned. Thus, acute administration of a nonintoxicating dose of MK-801 disrupts the retention of new information learned under the influence of the drug but does not interfere with the performance of tasks that are well learned before the drug is administered. Whether the performance deficits on the spatial learning tasks observed only following intoxicating doses of MK-801 reflect an effect on memory is not clear.  相似文献   
77.
目的:获得起效快、复原快的肌肉松驰剂。方法:1类化合物以汉防乙甲素为原料,经季铵化制得。Ⅱ类以阿曲库铵的结构为模板,对其1-取代基进行结构改造而得,所有目的化合物的结构经IR、^1HNMR、MS鉴定。结果:设计合成了未见文献报道的11个两类双苄基异喹啉季铵类化合物。结论:初步药理试验表明,目的化合物1c的起效剂量、起效时间与汉肌松相当。  相似文献   
78.
观察中晚期原发性肝癌病人在口服呋喃氟尿嘧啶的基础上加用消炎痛 (吲哚美辛 ) (治疗组 )和不加用消炎痛 (对照组 )外周血自然杀伤 (NK)细胞及T淋巴细胞亚群的变化。结果发现 :治疗组治疗后NK细胞活性较治疗前及较对照组治疗后显著提高 (P <0 .0 5 ,P <0 .0 1) ,而T淋巴细胞亚群的变化差异无显著性。提示消炎痛能增强中晚期原发性肝癌NK细胞的活性  相似文献   
79.
子宫腺肌病误诊原因分析及术前诊断临床探讨   总被引:5,自引:0,他引:5  
段社教  申延琴 《河北医学》2000,6(9):790-792
目的;探讨子宫腺肌病误诊原因及近年术前诊断研究进展,方法;对我院近10年收治的197例腺肌病患者的临床资料进行回顾性分析。结果:1990年元月至1997年12月128例腺肌病患者术前,术后诊断符合率仅为29.7%,术后误诊,漏诊率达70.3%,1998年元月至1999年12月69例术前经测定血清CA125及 腔双氧水造影后误诊,漏诊率降为27.5%术前主要误诊为子宫肌瘤或(和)子宫内膜异位症,结论  相似文献   
80.
缪鹰 《河北医学》2000,6(9):813-816
目的:探讨尿五种微量蛋白测定在糖尿病肾病(DN)早期诊断中的诊断价值。方法:采用放射免疫分析法(RIA)检测30例正常人及98例非胰岛素依赖性糖尿病(NIDDM)患者尿液;α1-微球蛋白(α-MG),β2-微球蛋白(β2-MG)Tamm-Horsfall蛋白(THP),白蛋白(ALb)及免疫球蛋白G(IgG)含量。结果:随着CCr值的下降,尿α1-MG,β2-MG,ALb及IgG排泄量逐渐增高,而  相似文献   
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