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31.
目的 :探讨肝硬化门脉高压病人门静脉和肝动脉彩色多谱勒血流参数变化的意义。方法 :肝硬化伴食道静脉曲张的病人 6 6例 ,正常人对照组 5 8例。测量门静脉血流速度 (PVV)和肝动脉阻力参数 (HA- PI) ,计算肝血管指数。结果 :在肝硬化门脉高压病人比对照组 PVV明显降低 (12± 2 .2 ) cm/ s;(15 .8± 2 .6 ) cm/ s,P<0 .0 0 1)和 HA- PI明显增高(1.3± 0 .15 ;0 .94± 0 .16 ,P<0 .0 0 1) ,肝血管指数明显减低 [(8.6± 2 .1) cm/ s;(16 .7± 4 .2 ) cm / s,P<0 .0 0 1) ]。彩色多谱勒血流参数 PVV、HA- PI、肝血管指数对肝硬化门脉高压的诊断的敏感性和特异性分别为 89%、84 %、83%、81%、95%、91%。结论 :肝血管指数对肝硬化门脉高压的诊断的敏感性和特异性更高。 相似文献
32.
Kenzi Takamura 《Ecotoxicology (London, England)》1995,4(4):245-257
The effect of the surfactant LAS was investigated on chironomid emergence using six outdoor artificial channels. The concentrations of LAS were mostly between 1 and 2 mgl-1 in the three treated channels. Chironomus yoshimatsui, Cricotopus tamapullus, Eukiefferiella coerescens, Eukiefferiella sp. and Thienemanniella majuscula were the major chironomids obtained with emergence traps. The number of midges trapped did not differ significantly between the treatment and the control for either of the species. On the other hand, the ratios of midges failing to emerge to the total midges trapped was significantly higher in the treatment than in the control for all of the species. The results show that chironomids emergence is difficult as a result of LAS treatment probably due to the lowered surface tension. 相似文献
33.
高频喷射通气时麻醉犬动脉血二氧化碳分压的估计 总被引:2,自引:0,他引:2
作用测定5-8次常频呼吸后呼气末二氧化碳分压的方法,探讨了高频喷射通气时麻醉犬动脉脉血二氧化碳分压与Petco2的关系,结果表明,在通气频率分别为60,100及200次/min时,Petco2和Paco2均无显性差异,Petco2呈显相关(r=0.83,P<0.01)。结果提示,测定5-8次常频呼吸后的Petco2可较准确地评估HFJV时麻醉犬的Paco2。 相似文献
34.
35.
经闭孔无张力尿道中段悬吊术治疗女性压力性尿失禁 总被引:1,自引:0,他引:1
目的探讨经闭孔无张力尿道中段悬吊术(trans-obturator tension free vaginal tape,TVT-O)治疗女性压力性尿失禁(stress urinary incontinence,SUI)的临床疗效。方法2006年1月~2007年9月,对15例SUI行TVT-O,取阴道前壁纵行切口1cm,组织剪分离尿道旁阴道黏膜下间隙至闭孔膜,放入蝶形导引杆,将螺旋形穿刺针沿导引杆紧贴耻骨下支穿过闭孔膜,从大腿根部皮肤穿出,将吊带无张力放置于尿道中段下方。结果手术时间15~40min,平均30min。术中出血量10~40ml,平均20ml。术中无并发症。1例术后尿潴留,留置尿管5d后缓解。10例术后大腿根部疼痛,术后3~10d消失。15例随访2~19个月,平均8个月,均治愈,无复发。结论TVT-O操作简单、安全有效。 相似文献
36.
关节镜下经皮张力带钢丝固定治疗髌骨骨折 总被引:1,自引:0,他引:1
目的探索髌骨骨折错位在关节镜下复位、内固定的新方法。方法对56例新鲜闭合性横断型髌骨骨折病例,在关节镜下冲洗关节腔积血,清除骨折断端凝血块,去除小的骨碎片,进行髌骨复位,直接观察关节面复位对合情况。应用胥氏张力带钢丝固定原理,经皮穿入克氏针及钢丝,针孔做1cm小切口,完成内固定。结果术后2周绝大部分患者屈膝可达90°以上,骨折在6~10周达到临床愈合,出现针尾触痛者8例,克氏针松动上移2例,无钢丝断裂及脱落。治疗效果按膝关节损伤患者的功能评定法,优良率为96.4%。结论本术式两枚克氏针各有一根钢丝固定,在关节镜导引下,经皮穿针钢丝固定,不会因两根针位置不对称而产生扭距。操作方法简便、有效,有利于术后早期功能锻炼,为髌骨骨折提供了一种新的手术方法。 相似文献
37.
目的 比较无张力腹股沟疝修补术与传统腹股沟疝修补术在老年患者中应用的临床结果、术后生活质量和经济开支。方法 自2000~2001年60岁以上的老年患者42例行腹股沟疝无张力修补术与42例行传统腹股沟疝修补术者,分类比较。结果 无张力腹股沟疝修补术对于老年患者在复发率、术后镇痛、手术时间和术后下地时间方面均明显优于传统腹股沟疝修补术。结论 无张力腹股沟疝修补术运用在老年患者中,近远期效果均优于传统修补手术。 相似文献
38.
C. F. POETS A. ARNING W. BERNHARD C. ACEVEDO & H. VON DER HARDT 《European journal of clinical investigation》1997,27(4):293-298
Alveolar surfactant is well known for its ability to reduce minimal surface tension at the alveolar air–liquid interface to values below 5 mN m?1. In addition, it has been suggested that surfactant is also present in the airways, particularly in the perinatal period. We isolated surfactant from pharyngeal aspirates obtained from 33 neonates immediately after delivery and analysed it for both phospholipid (PL) composition and surface tension function. PL classes and phosphatidylcholine (PC) molecular species were determined by normal and reversed-phase high-performance liquid chromatography (HPLC), respectively. Static and dynamic surface properties of the surfactant were studied in a pulsating bubble surfactometer. Sample volume was 1.3 ± 0.5 mL (mean ± SD) with a total amount of 2.5 ± 1.3 μmol of PL and a concentration of 2.1 ± 1.0 μmol mL?1 PL. HPLC analyses of PL classes revealed a composition identical with surfactant prepared from alveolar washes, i.e. PC 83.6 ± 2.1%, sphingomyelin 1.4 ± 0.5%, phosphatidylglycerol 8.1 ± 1.6%, phosphatidylethanolamine 2.1 ± 0.5% and phosphatidylinositol 2.6 ± 1.1%. Thin-layer chromatography showed almost identical results but was more time-consuming and needed more material for analysis. Analysis of PC molecular species revealed a composition typical of human alveolar surfactant with 54.7 ± 3.9% dipalmitoyl PC, 10.3 ± 1.9% palmitoyloleoyl PC and 9.1 ± 1.5% palmitoylmyristoyl PC. Minimal surface tension fell to values below 5 mN m?1 within 5 min of cycling in all subjects. The methods used in this study allowed for complete PL and surface tension analyses of surfactant obtained during routine pharyngeal suctioning after delivery at term. Whether they are also applicable to preterm neonates with respiratory distress remains to be determined. 相似文献
39.
Rogelio Leira José Castillo Francisco Martinez José Maria Prieto Manuel Noya 《Cephalalgia : an international journal of headache》1993,13(5):346-348
We measured platelet-rich plasma (PRP) serotonin in patients suffering from tension-type headache, before and after treatment with amitriptyline, comparing them with a healthy control group and patients with untreated depression. We evaluated the severity of headache and depression in each group. PRP serotonin levels were higher in patients with headache than in controls and depressed patients. We observed a fall of PRP serotonin in patients with tension-type headache to similar levels after treatment as the depressed group. This fall was correlated with the improvement of headache but not with depression scales. Our data suggest that the rise of platelet serotonin levels in tension-type headache is related to pain and not depression. 相似文献
40.
An investigation of the feasibility and validity of measurement of the conjunctival oxygen tension as a monitor of peripheral circulation, blood and extracellular fluid volume and cerebral circulation was carried out in 7 healthy volunteers and 5 unconscious critical care patients with proven total cerebral infarction. The healthy volunteers were subjected to changes in hydration achieved by the administration of furosemide and subsequent rehydration by administration of normal saline. Conjunctival oxygen tension was found to be a sensitive indicator of changes in the degree of hydration presumably by its ability to detect changes in peripheral circulation depending upon circulating blood and extracellular fluid volume. A drawback is that other stimuli of the sympatho-adrenergic system such as temperature and pain, interfere with measurement in the conscious volunteer. In patients with presumed total brain infarction the conjunctival PO2 cannot be used as a reliable monitor of cerebral blood flow because of varying perfusion of the palpebral conjunctiva from the external carotid artery in the occasional patient. 相似文献