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51.
Sarraf-Yazdi S Sheng H Grocott HP Bart RD Pearlstein RD Steffen RP Warner DS 《Brain research》1999,826(2):381-180
This study examined the effect of a pharmacologically induced rightward shift in the partial pressure of oxygen at which 50% of hemoglobin is saturated (P50) on outcome from transient focal cerebral ischemia in the rat. Halothane anesthetized rats (n=20 per group) were given saline or a single 15-min infusion of 150 mg/kg RSR13 (2-[4-[[3,5-dimethylanilino) carbonyl]methyl]phenoxy]-2-methylproprionic acid) intravenously before or 30 min after onset of 75 min of middle cerebral artery filament occlusion (MCAO). Seven days later, severity of hemiparesis and cerebral infarct size were examined. RSR13 alone did not significantly improve outcome. Conscious normothermic rats (n=12 per group) were also given RSR13 (150 mg/kg) or 0.9% NaCl intravenously and subjected to 75 min of MCAO with 7 days of recovery. Again, RSR13 alone did not significantly reduce infarct size or improve neurologic score. A dose-response curve for dizocilpine (MK-801) was then constructed in conscious normothermic rats subjected to 75 min of MCAO. Dizocilpine (0.5 mg/kg i.v.) caused a 90% reduction in mean infarct size while 0.25 mg/kg reduced infarct size by 48%. Other rats were then subjected to 75 min of MCAO after being given dizocilpine (0.25 mg/kg i.v.; n=18) or RSR13 (150 mg/kg i.v. )+dizocilpine (0.25 mg/kg i.v.; n=15). RSR13+dizocilpine resulted in smaller cortical infarct volume (8+/-14 mm3 vs. 34+/-37 mm3, p<0.02) and total cerebral infarct volume (46+/-28 mm3 vs. 81+/-60 mm3, p<0. 05) compared to dizocilpine alone, respectively. We conclude that a pre-ischemic peak increase in P50 of approximately 25 mmHg alone is insufficient to reduce focal ischemic injury, but may be advantageous when used in conjunction with other neuroprotective agents. 相似文献
52.
Mechanism of action of amiloride: a molecular prospective 总被引:1,自引:0,他引:1
Amiloride is a prototypic inhibitor of epithelial sodium channels. Rapid progress has been made in our understanding of the structure of the sodium channel and related cation-selective channels. This work, coupled with experiments examining how selected sodium channel mutations affect amiloride binding, provides critical clues towards defining sites within the channel that bind amiloride. Residues within the channel pore and within its extracellular domain participate in amiloride binding. These results suggest that sites that interact with amiloride within the channel's extracellular domain may be in close proximity to residues within the channel's pore. 相似文献
53.
我国烧伤外科的进展与展望 总被引:4,自引:0,他引:4
一、烧伤外科光辉的41年与兄弟学科相比,烧伤外科起步相对较晚,刚刚度过“不惑之年”。虽然学科年轻,但发展迅速,临床治疗达到世界领先水平,基础研究亦跻身于世界先进行列。我国烧伤专业的发展大体经历了三个阶段[1]。1958年由于土法上马全民大炼钢铁,致使烧伤患者骤然增多。北京、上海、重庆、西安等大城市率先在几个大医院成立了烧伤专科。上海瑞金医院成功地救治了烧伤面积89%,Ⅲ度烧伤23%的钢铁工人邱财康。这一史无前例的医学奇迹,震惊了世界,也鼓舞了国人。进入60年代全国各地先后成立了烧伤科或组建了烧伤… 相似文献
54.
Sheng C. Fang 《Archives of environmental contamination and toxicology》1981,10(2):193-201
Mercury vapor sorption by soil increased curvilinearly with the increase of soil moisture content until a maximum was reached. A further increase of moisture content caused a decline in mercury sorption. The percent moisture contents which gave maximal increase of203Hg vapor sorption in these soils coincide quite closely with their water-holding capacity values at 1/3 bar.Soil microorganisms may play a part in moist soil for the increase of elemental mercury vapor sorption and subsequent transformation to mercuric form.Mercury vapor diffused into both dry and moist soil columns and the diffusion profile can be described by an exponential function of the form, y=ae–bx, where a is the adsorption characteristics of the soil, b is the diffusivity coefficient and x is the depth of soil. The diffusivity coefficient for mercury vapor varied with the soil type and its moisture content.Supported in part by grant R-803948 from the U.S. Environmental Protection Agency. Technical Paper No. 5489, Oregon Agricultural Experiment Station. 相似文献
55.
Biochemical and metabolic indicators were monitored in a group of volunteers suffering from a variety of chronic illnesses participating in a week's course on a special uncooked vegetable diet, known as "living food". Unmatched healthy controls ate the same diet cooked for 2 min in a microwave oven. After 1 week on the regimen, serum protein and urea contents decreased and alanine aminotransferase (ALAT) activity increased in both groups, although all within the normal range. Blood glucose increased in both groups to slightly above normal limits but total serum cholesterol dropped about 1 mmol/l from normal starting levels. Serum tocopherol and retinol increased only in the group eating the uncooked diet. In both groups urinary sodium dropped drastically without a significant change in potassium. Serum and urinary phenol and p-cresol diminished also significantly. It is concluded that this vegetable diet may be of some benefit in the short term but any longer-term use requires evaluation. 相似文献
56.
六味地黄汤含药血清对海马神经元突触活动的影响 总被引:3,自引:1,他引:3
目的:研究六味地黄汤益智作用的机理。方法:应用血清药理学和电生理方法,观察六味地黄汤含药血清对原代培养大鼠海马神经元自发突触活动的影响。结果:含药血清作用48h可明显增加海马神经元自发动作电流(spontaneous action cur-rent,sAC)和微小兴奋性突触后电流(miniature excitatory post aynaptic currenl,mEPSC)的产生频率,但并不影响mEPSC的幅度。结论:六味地黄汤可作用于突触前位点对海马神经元突触活动产生调节作用,该作用可能是其调节海马神经元的兴奋性进而发挥益智作用的机制之一。 相似文献
57.
目的:观察纯中药制剂银康颗粒剂治疗银屑病的,临床疗效及治疗前后患者血粘度的变化。方法:将382例患者随机分为2组,治疗组252例应用银康颗粒剂治疗,对照组130例应用复方青黛胶囊治疗;对治疗组部分病例(212例)治疗前后血粘度指标进行观察。结果:治疗组治愈148例,好转82例,未愈22例,总有效率为91.12%;对照组治愈51例,好转46例,未愈33例,总有效率为74.62%,2组总有效率比较,差异有非常显著性意义(P<0.01)。治疗组患者治疗前后全血粘度差异无显著性意义(P>0.05),血浆粘度差异有显著性意义(P<0.05)。结论:风邪外袭、血虚生风、气滞血瘀是致病的主要原因。治疗应以清热祛风与养血活血并举。 相似文献
58.
59.
剖宫产术后硬膜外镇痛产妇血及初乳中吗啡含量的监测 总被引:2,自引:0,他引:2
目的 监测剖宫产术后硬膜外镇痛产妇血及初乳中的吗啡含量 ,探讨微量吗啡对新生儿的影响。 方法 选择剖宫产术的产妇 10 0例 ,分为实验组和对照组各 5 0例 ,两组均为连续硬膜外麻醉 ,穿刺点选择 L1 ~ L3,麻醉药为 2 %利多卡因 15~ 2 0 m l,在手术结束时 ,实验组将吗啡缓慢注入硬膜外管 2 mg然后拔管。于术后 1h取产妇的静脉血 3m l,采集产妇术后 3、6 h尿样及术毕 6~ 12 h采集新生儿尿样 3m l;在产后 4 8h内收集产妇的初乳 3~ 5 m l。 结果 观察组 96 % (48/ 5 0 )的镇痛效果较对照 16 % (8/ 5 0 )明显 ,差异有显著性 (P<0 .0 5 ) ,观察组血吗啡浓度 <5~ 118μg/ m l,初乳吗啡浓度 <5~ 30 .4μg/ L ,产妇尿 92 %呈阳性 ,新生儿尿 13.3%呈阳性。两组产妇和新生儿的生命体征比较差异无显著性。 结论 剖宫产术后硬膜外腔应用吗啡镇痛 ,产妇哺乳对新生儿没有影响 ,是安全可行的。 相似文献