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61.
目的探讨经支气管动脉灌注化疗(BAI)治疗晚期肺癌近期疗效的影响因素。方法回顾性分析1990年3月至2006年6月间胸部X线片复查资料相对完整的82例经BAI治疗的原发性晚期肺癌的近期疗效。结果完全有效(CR)10例(12.2%)、部分有效(PR)32例(39.0%)、轻微有效(MR)23例(28.0%)、稳定(SD)15例(18.3%)、进展(PD)2例(2.4%)。单因素方差分析结果显示,半月时肿瘤缩小率(TDR1/2month)(χ2=25.92,P<0.01)、BAI次数(TBAI)(χ2=17.70,P<0.01)、肿瘤大小(Tsize)(χ2=14.21,P<0.01)和肿瘤血供丰富程度(χ2=6.59,P<0.01)对近期疗效的影响具有统计学意义。对年龄、病理类型等12项协变量进行二项分类Logistic回归分析,采用向后删除法经10步二次迭代,得到Logistic回归方程:P(1)=1/[1 e-(-8.953 2.656TDR1/2month 1.382TBAI 1.230Tsize)],方程对BAI近期疗效有效与无效的预测正确率分别为85.7%和70.0%。结论第1次BAI后半月时的肿瘤缩小率、BAI治疗次数和肿瘤的大小是影响BAI近期疗效的因素。  相似文献   
62.
Summary Based on the study of the arterial distribution of 120 hepatic grafts removed from brain-dead patients, the authors assess the possibilities of vascular partition in cases of combined removal of the liver and pancreas. The discussion deals with the vascular distribution of each organ. The presence of a right hepatic artery arising from the superior mesenteric a. (SMA) requires preservation of the SMA with the hepatic graft, while the pancreas is removed with the celiac trunk (CT) and its branches. The presence of a left hepatic artery arising from the CT requires its preservation with the hepatic graft, the pancreas being removed with the SMA and the splenic artery.
Partage vasculaire des prélèvements hépatiques et pancréatiques combinés : bases anatomiques (28.5.93)
Résumé A partir de l'étude de la distribution artérielle de 120 greffons hépatiques prélevés sur des patients en état de mort cérébrale, les auteurs apprécient les possibilités de partage vasculaire en cas de prélèvement combiné foie-pancréas. La discussion porte sur la distribution vasculaire de chaque organe. L'existence d'une artère hépatique droite naissant de l'artère mésentérique supérieure (AMS) nécessite de conserver l'AMS avec le greffon hépatique, le pancréas est prélevé avec le tronc coeliaque (TC) et ses branches. La présence d'une artère hépatique gauche naissant du TC impose de le conserver avec le greffon hépatique, le pancréas est prélevé avec l'AMS et l'artère splénique.
  相似文献   
63.
鼻成形术中额颞部血管的应用解剖学研究   总被引:32,自引:4,他引:32  
目的:为解决临床上额部皮瓣修复鼻缺损时常出现的血运障碍,全鼻再造时的衬里缺损以及应用耳廓复合组织修复鼻翼缺损时面积受限等问题。方法:对29例(58例)尸体额、鼻和颞部血管进行解剖。结果:滑车上动脉由两侧向内上行走,滑车上动脉的分支、眶上动脉的浅支、颞浅动脉额支的额眶支相互吻合成网前额动脉吻合网。颞浅动脉主干及顶支发出2~3支耳支分布至耳轮。结论:额部皮瓣应设计在旁正中的滑车上动脉血管走行轴线上;可同时用两侧额部皮瓣行全鼻缺损的修复;亦可经前额动脉吻合网、颞浅动脉及其分支,设计出带蒂的大面积耳廓复合组织岛状瓣修复大面积鼻翼缺损或半鼻缺损  相似文献   
64.
路伟  舒先红 《解剖学杂志》1998,21(5):379-383
血管内超声是利用安装在心导管顶端的微型超声探头从管腔内观察血管形态学的新技术,为了解其对人体动脉实时显像的能力及定量定性的准确性,在自行设计的实验模型装置上的对9段经生理压力固定的人离体外周动脉进行超声显像,然后将血管组织对应切片观察,对比二者结果发现:(1)血管内超声可准确测定动脉腔面积,周长,直径和厚度等重要参数,与组织学测值相关系数均在0.95以上(P〈0.001);(2)肌性和弹性动脉组织  相似文献   
65.
目的:分别对正常人和脑梗死患颈动脉血流超声多普勒时频分析,为临床应用提供参考资料。方法:检测正常人和脑梗患(大多有颈动脉粥样硬化斑块)的颈动脉多普勒血流时频谱,以其峰值频率(fmax),模式频率(fmode),平均频率(fmean),低值频率(fmin),重脉波频率(fp)和频弥散宽度(fw)为定量指标。结果:正常人颈动脉血流信号时频谱的fmax,fmean和fmode曲线在一个心动周期中具有总体相似的形状,相互嵌套,其中收缩期的fmax最高,均大于3kHz,fmin最低不低于1kHz,脑梗死患颈动脉时频谱的fmax与fmean和fmode两曲线分开,fmax减低(<3kHz),fp消失,舒张末期fmin减低显(均低于0.5kHz),结论:颈动脉多普勒血流时频分析及所遴选的定量指标对颈动脉粥样硬化斑块十分敏感,可供诊断试验,且可集成在便携式计算机里,适用于社区人群中筛选易中风病变个体。  相似文献   
66.
脐动脉多普勒血流测定在肝内胆汁淤积症的应用   总被引:1,自引:1,他引:0  
目的:评价脐动脉多普勒血流测定(S/D)与无钢荷试验(NST)在妊娠期肝内胆汁淤积症(ICP)中的应用价值。方法:应用S/D与NST对孕龄为35~40周157例ICP患者进行动态监测,并对新生儿Apgar评分和羊水粪染的情况进行比较。结果:脐动脉血流S/D〈3、NST≥7分,胎儿预后良好;脐动脉血流S/D≥3、NST〈7分,胎儿预后不佳,两者差异有显著性(P〈0.005)。结论:脐动脉多普勒血流检测弥补单纯NST对ICP患者胎儿预后判断的不足,提高临床诊断准确率。  相似文献   
67.
MN9202保护血栓大鼠尾动脉血管作用   总被引:4,自引:0,他引:4  
观察新二氢吡啶类钙拮抗剂2,6-二甲基-4-(3-硝基苯基)-1,4-二氢-3,5-吡啶二羧酸-3-甲酯-5-正戊酯(MN9202)对血栓形成大鼠尾动脉血管平滑肌及内皮功能的影响。方法大鼠脚趾sc注射角叉来胶制备血栓模型,并于注射角叉菜胶前24h,1h及注射后24hipMN92021μMOL.KG^-1,取尾动脉血栓波及不同区域的三段血管,以去甲肾上腺素(NE),乙酰胆碱(ACh),亚硝酸钠(Na  相似文献   
68.
  1. Rat mesenteric arteries (∼250 μm) were set up in a single-channel isometric myograph designed to allow fluorescence measurements concurrent with field stimulation of intramural nerves. Vessels were loaded with 6 μM fura-2AM for 2 h and simultaneous recordings of neurogenic contraction (force) and intracellular calcium [Ca2+]i were obtained. In other experiments, arteries were loaded with 1 μCi ml−1 [3H]-noradrenaline (NA) for 30 min in order to measure release of [3H]-NA in response to field stimulation to examine whether ryanodine directly inhibited neuronal release of NA.
  2. Arteries were activated by single intermittent field stimulation or continuously to excite intrinsic sympathetic nerves, or by cumulative addition of noradrenaline (1 nM–10 μM) to the bathing solution.
  3. Pre-incubation with ryanodine markedly inhibited the contraction and [Ca2+]i release in response to single-pulse nerve stimulation. Ryanodine also inhibited an early phasic component of the response to continuous field stimulation and reduced the rate of rise in force in response to continuous field stimulation. However, stable maximal contraction and [Ca2+]i in response to continuous field stimulation as well as maximal responses to exogenous NA were unaffected. Release of [3H]-NA in response to single intermittent field stimulation was not affected by ryanodine when compared to vehicle.
  4. Our results suggest that brief intermittent activation of intramural sympathetic nerves increases [Ca2+]i and contracts small arteries primarily by releasing Ca2+ from a ryanodine-sensitive intracellular store. In contrast, the stable rise in tone and [Ca2+]i resulting from continuous nerve stimulation may largely depend on sources of Ca2+ other than the ryanodine-sensitive intracellular store.
  相似文献   
69.
  1. This study set out to examine the endothelin receptor subtypes mediating vasoconstriction in the rat renal arcuate artery. This was done in isolated vessels 120–200 μm in diameter, incubated with a selective agonist and the novel ‘antisense'' peptide to part of the human endothelinA receptor.
  2. Groups of vessels (n=6) were incubated with increasing concentrations of endothelin-1 (ET-1), from 1 to 100 nM, which caused a 65% maximal contraction at the highest dose with an pEC50 of 8.16±0.11 M. By contrast, in six other vessels sarafotoxin 6c over the same dose range gave a minimal contraction (around 5% of maximum).
  3. Preincubation of six vessels with the antisense peptide ETR p1/f1 at 1 μM had no effect on the ET-1 induced vasoconstriction, in terms of displacement of the concentration-response curve or the maximal tension achieved by the agonist. In the six vessels exposed to 4 μM ETR p1/f1, there was a significant shift of the concentration-response curve and a lower pEC50 at 7.78±0.09 M (P<0.05). At the highest concentrations of ETR p1/f1, there was a marked suppression of all responses to ET-1, which at the maximal concentrations tested, 0.1 μM, only reached some 10% of the maximal achievable contraction.
  4. Increasing ET-1 concentrations up to 2 μM in vessels incubated with 40 μM ETR-p1/f1 showed that the blockade could be overcome and that the relationship was shifted to the right (P<0.001) by approximately one log unit with a pEC50 of 7.13±0.11 M. A Schild plot of the data indicated the antagonist to be acting competitively at a single population of receptors.
  5. At the highest concentrations tested, 40 μM, ETR-p1/f1 had no effect on noradrenaline-induced contractions, indicating a lack of non-specific actions.
  6. Together, these data suggest that at the rat renal arcuate artery the endothelinA receptor is the predominant functional receptor mediating contraction. Furthermore, this study has shown the potential usefulness of this novel type of ‘antisense'' peptide in blocking receptor activation.
  相似文献   
70.
Oxygen-derived free radicals, in particular superoxide anions, are known to inactivate the endogenous vasodilator endothelium-derived relaxing factor (EDRF) which is probably identical with the gaseous radical nitric oxide. It is possible that EDRF is not the target of superoxide anions but may also be an endogenous scavenger of this radical.Superoxide anions generated by the vessel wall were measured by a modified lucigenin-enhanced chemiluminescence technique in isolated pig coronary artery rings with intact endothelium.The addition of bovine superoxide dismutase, a scavenger of superoxide anions, decreased the chemiluminescence signal by 40 ± 26% (mean ± SD; P < 0.05; n = 21) indicating reduced generation/release of superoxide anions. In contrast, pretreatment of coronary artery rings with diethyldithiocarbamate, an inhibitor of the intrinsic copper-zinc superoxide dismutase, increased the chemiluminescence response by 136 ± 128°10 (P < 0.05; n = 21). This increase in the chemiluminescence response induced by diethyldithiocarbamate-pretreatment was almost abolished in the presence of added bovine superoxide dismutase. Specific inhibition of the EDRF release with nitro-l-arginine (100 M) did not affect the chemiluminescence response. On the other hand, stimulation of the EDRF release by substance P (10 nM) or addition of the endothelium-mediated relaxant bradykinin (0.1 M) did not affect the chemiluminescence response. Stimulation of the EDRF release with serotonin (0.1 M) significantly reduced the photon emission by 15 ± 16% (n = 27). However, this effect of serotonin on the chemiluminescence response could not be prevented by specific inhibition of the EDRF release with nitro-l-arginine (100 M) but could be prevented by buffering the acidic serotonin solution with NaOH to pH 7.4.Our results suggest that basal and agonist-stimulated release of EDRF in isolated pig coronary artery rings does not interfere with the basal generation/release of superoxide anions derived from the vascular wall. Correspondence to: A. Mugge at the above address  相似文献   
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