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21.
Thyrotoxicosis is known to exacerbate bronchial asthma. Leukotrienes C4, D4 and E4 have the capacity to constrict airway smooth muscle and impair pulmonary compliance. A rationale is hereby suggested whereby thyroid hormones are implicated in the synthesis of leukotrienes C4, D4 and E4.  相似文献   
22.
A review of 3 current radiosurgery systems   总被引:3,自引:0,他引:3  
BACKGROUND: Stereotactic radiosurgery and fractionated stereotactic radiotherapy have become widespread techniques applied to the treatment of a variety of intracranial lesions. Rapid evolution of new technologies has now enabled clinicians to treat tumors outside the cranium and down the spinal axis. This review compares 3 commercially available systems in widespread use throughout the world. METHODS: Literature review and interviews with practitioners in the United States were performed to establish data for a comparative analysis of the Gamma Knife (Elekta, Sweden), Novalis (BrainLabs, Germany), and CyberKnife systems (Accuray, Sunnyvale, CA). Cost analyses were deliberately excluded because of the need for detailed cost-benefit analysis beyond the scope of the review. RESULTS: An unbiased comparative analysis was not possible because of the lack of objective data from a standard metric for these systems. Despite this shortcoming, disparate features of each system were compared and contrasted. CONCLUSION: A careful assessment of each system, including its operational features, capabilities, and yearly capacity must be weighed against the composition of the radiosurgery team, the case mix of the practice, and the objectives of the clinical unit to yield the best fit.  相似文献   
23.

Background

Patients in chronic phase of myocardial infarction (MI) have decreased coronary flow reserve (CFR) in infarct related artery (IRA) that is proportional to the extent of microvascular/myocardial damage. We proposed a novel model for the assessment of microvascular damage and infarct size using Doppler echocardiography evaluation of CFRs of the IRA (LAD) and reference artery (RCA).

Methods

Our study included 34 consecutive patients (28 men, mean age 50 ± 11 years) with first anterior STEMI and single vessel disease successfully treated with primary PCI. All patients underwent SPECT MPI for the assessment of infarct size (expressed as a percentage of myocardium with fixed perfusion abnormalities) and CFR evaluation of LAD and RCA. CFR derived percentage of microvascular damage (CFR PMD) was calculated as: CFR PMD = (CFR RCA − CFR LAD) / (CFR RCA − 1) × 100 (%).

Results

CFR PMD correlated significantly with all parameters evaluating the severity of myocardial damage including: peak CK activity (r = 0.632, p < 0.001), WMSI (r = 0.857, p < 0.001), ejection fraction (r = − 0.820, p < 0.001), left ventricular end diastolic (r = 0.757, p < 0.001) and end systolic volume (r = 0.794, p < 0.001). Most importantly, CFR PMD (22 ± 17%) correlated significantly with infarct size by SPECT MPI (21 ± 17%) (r = 0.874, p < 0.001).

Conclusions

CFR PMD derived from the proposed model was significantly related to echocardiographic and enzymatic parameters of infarct size, as well as to myocardial damage assessed by SPECT MPI in patients with successfully reperfused first anterior STEMI.  相似文献   
24.
This review discusses the involvement of patients in the reporting of adverse drug reactions (ADRs). Patients benefit from drugs but also experience their adverse effects. Since concerns about the safety of drugs are also patients’ concerns, the patient could also play a part in decreasing the risks of drug therapy. Patient interest in the safety aspects of drugs is evident. At an international level, the merits of patient reports are being considered. To date, the literature does not yet provide any actual results in relation to the detection of ADRs by patients. Different considerations regarding ADR reporting by patients are discussed. The authors conclude that we should positively value patients’ involvement in drug therapy and their concern regarding possible adverse effects. As a consequence, patients’ reports on ADRs should be accepted.  相似文献   
25.
云克联合免疫抑制剂治疗活动期Graves''眼病患者   总被引:9,自引:0,他引:9  
采用随机对照的方法,研究云克治疗方案,免疫抑制治疗方案以及联合治疗方案(云克联合免疫抑制剂)对活动期的GO患者的治疗效果。经过4个月治疗后,免疫抑制治疗方案(n=22)的总有效率为19/22,严重副作用的发生率为8/22;云克治疗方案(n=20)的总有效率17/20,严重副作用的发生率为2/20;联合治疗方案(n=24)的总有效率22/24,严重副作用的发生率为2/24;结果表明联合应用免疫抑制剂及云克治疗活动期的GO患者,既能取得较满意的疗效,又克服了长期应用激素治疗带来的副作用以及停用激素后的反弹。  相似文献   
26.
27.
艾叶油的呼吸系统药理研究-Ⅱ,抗过敏作用   总被引:9,自引:1,他引:9  
目的:本文研究艾叶油的抗过敏作用。方法:采用致敏豚鼠气管SchultzDale 反应,组胺或氨甲酰胆碱引起的豚鼠气管收缩,大鼠被动皮肤过敏,5羟色胺引起的大鼠皮肤毛细血管通透性增强,豚鼠肺组织释放过敏性慢反应物质(SRSA) ,SRSA 收缩豚鼠回肠等试验。结果:艾叶油抑制致敏豚鼠气管SchultzDale 反应(IC50 :98 .6mg/L) ;100mg/L 明显降低组胺或氨甲酰胆碱引起的豚鼠气管收缩pD2 值;明显抑制大鼠被动皮肤过敏(ID50 :0 .22g/kg) 和5羟色胺引起的大鼠皮肤毛细血管通透性增强反应(ID50 :0 .52g/kg) ;抑制豚鼠肺组织释放SRSA(IC50 :49 .7mg/L) ;拮抗SRSA 对豚鼠回肠的收缩(IC50 :34 .9mg/L) 。结论:艾叶油具有抗过敏作用,对呼吸道过敏反应有保护作用,是其治疗支气管哮喘和慢性气管炎作用机制之一  相似文献   
28.
目的 探究StereoPhan(SP)模体与SRS MapCHECK(SMC)半导体矩阵用于脑转移瘤患者HyperArc(HA)计划剂量验证的可行性。方法 选取16例在北京协和医院接受HA放射治疗的脑转移瘤患者为研究对象,分别将电离室和SMC半导体矩阵插入SP模体,测量患者的HA验证计划的点剂量与平面剂量,并与治疗计划系统(TPS)计算数据对比,平面剂量的γ分析标准取2 mm/3%、2 mm/2%、1 mm/3%和1 mm/2%。结果 16例患者的点剂量平均偏差是1.33%±0.84%,平面剂量γ通过率在2 mm/3%、2 mm/2%的标准下依次为99.72%±0.46%、98.93%±1.32%,在 1 mm/3% 、1 mm/2%的标准下依次为98.85%±1.79%、97.13%±3.19%。结论 SP模体与SMC半导体矩阵适合用于开展脑转移瘤患者HA计划的剂量验证工作,在进行点剂量和平面剂量验证时,可以分别采用3%和1mm/2%的分析标准。  相似文献   
29.
30.
目的:比较脑转移立体定向放射外科中共面与非共面模式下剂量学差异,对单组非共面模式在脑转移立体定向放射外科中的应用进行可行性分析。方法:回顾性分析14例脑转移患者,采用容积旋转调强放疗与无均整块技术技术,处方剂量25 Gy,在计划设计中用共面弧、单组非共面弧、多组非共面弧3种模式,比较3种模式下靶区剂量、适形指数(conformity Index,CI)、梯度指数(gradient index,GI)和脑组织受量以及出束时间、执行效率等差别。结果:共面计划无论相对于单组非共面计划还是多组非共面计划而言,出束时间以及CI差异均无统计学意义(P>0.05)。3种模式都能达到临床要求,但剂量分布上差异有统计学意义。共面计划中GI(GI50=4.84±0.52,GI25=16.13±2.73),要远远高于单组非共面计划GI(GI50=3.66±0.44,GI25=9.94±1.41)(P <0.001,P <0.001)和多组非共面计划GI(GI50=3.73±0.42...  相似文献   
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