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21.
为进一步研究呼吸道疾病时的粘液纤毛清除功能,采用99mTc-DTPA气溶胶吸入显像,通过电影显示定性和定量指标分析.对18 例健康受试者和患者进行了显像研究,得到气道清除率和粘液纤毛清除率的正常值,并观察了32例慢性阻塞性肺病(COPD)患者气管-支气管纤毛清除功能的改变.结果显示,健康受试者与COPD患者粘液纤毛清除率(mm/min)分别为3.89±0.92和1.32±0.59,两者比较有显著性差异(P<0.01),COPD患者不同时间气道清除率和粘液纤毛清除率均明显低于健康受试者(P<0.01).本研究方法简便客观,具有定性观察和定量分析的优点,对于呼吸系统其它疾病(如支气管扩张、原发性纤毛无运动)的研究及药物疗效的评价具有重要的临床实用价值.  相似文献   
22.
Ethyl cysteinate dimer (ECD) labelled with reduced technetium-99m has recently been proposed as a promising radiopharmaceutical for brain perfusion imaging. In the present study a single-component kit formulation has been developed, thus simplifying the radiolabelling procedure. A method of analysis by electrophoresis has also been developed, permitting identification of radiochemical impurities in the preparation. 99mTc-ECD prepared by the single-component kit was further evaluated in primates and humans. The results demonstrated that the complex is stable in vivo, rapidly extracted and retained in the brain tissue for a sufficient time for single-photon emission tomography studies. Therefore the present single-component kit formulation can be proposed as a reliable instant freeze-dried kit for routine preparation of 99-Tc-ECD required for scintigraphic assessment of regional cerebral blood flow.  相似文献   
23.
Brain single-photon emission tomography (SPET) withN,N-1,2-ethylene-diylbis-l-cysteine diethyl ester dihydrochloride (ECD) was performed on ten patients with a clinically high grade late whiplash syndrome and on 11 controls. Two independent readers blinded to the clinical diagnosis were able to separate the ten patients from normal controls. All these patients had qualitative bilateral parieto-occipital hypoperfusion. To confirm this, the perfusion rate of parieto-occipital over global (perfusion index) was calculated after drawing elliptical regions of interest in transversal-oblique slices. The perfusion indices in patients were significantly lower than in controls as tested by the Mann-WhitneyU test. This quantitative study proves our recent qualitatively analysed observation (Lancet 1995; 345: 1513–1514).  相似文献   
24.
The quantification of myocardial perfusion abnormalities is necessary to allow comparison of repeated studies, especially in the evaluation of the success of medical, interventional or combined treatment in stable coronary artery disease or in evolving myocardial infarction. The purpose of this study was to assess inter-observer reproducibility of tomographic study processing using a semi-automatic quantitative programme. Technetium 99m hexakis-2-methoxyisobutylisonitrile (99mTc-Sestamibi) was chosen for tomographic imaging of repeated rest-stress studies in patients with stable coronary artery disease. The quantification was performed using a modification of the Cedars polar coding and comparison with the normal data base. The perfusion defects were quantified separately for each standard perfusion area [left anterior descending (LAD), right coronary (RCA) and left circumflex (LCX) arteries] and total area of hypoperfused myocardium. The inter-observer variability for 40 tomographic studies was accomplished. The defects were the largest in the LAD perfusion area (average 19.7% of the normalized LAD supply area) with an inter-observer correlation of 0.84 for this region. The greatest variability was found for the LCX region (r=0.55) and is attributed to a small average perfusion defect (7.1%), only 18 studies having abnormal perfusion in this area. In total, an average 14.3% of the left ventricular myocardium was significantly hypoperfused, and the inter-observer correlation was 0.87. These results show good inter-observer reproducibility using semi-automatic quantitation of perfusion defects. Careful interpretation of smaller defects in the evaluation of treatment results is advised when repeated 99mTc-Sestamibi single photon emission tomography studies are processed by more than one observer.The work was performed at Nuclear Medicine Department in Ulm. Offprint requests to: M. Milinski  相似文献   
25.
目的观察化疔增敏剂对多药耐药性(Multi-drug resistance,MDR)肿瘤细胞 P-糖蛋白(P-glycoprotein,P-gp)的影响及伴随~(99)Tc~m-MI-BI 摄取动力学的变化,以建立用~(99)Tc~m-MIBI 来评价化疗增敏剂效果的方法。方法 MDR 人乳腺癌细胞 MCF-7/Adr 37℃培养。(1)实验组和对照组细胞培养基中分别加入化疗增敏剂维拉帕米(10 μmol/L)和等体积培养液 DMEM。~(99)Tc~m-MIBI 与细胞共同孵育2 h 后收集细胞,测定放射性活度和 P-gp 表达水平。(2)维拉帕米(10 μmol/L)加入细胞培养基中,与细胞孵育若干时间后~(99)Tc~m-MIBI 加入细胞培养基中,与细胞一起培养2 h 后收集细胞。测定放射性活度和P-gp 表达水平。结果 (1)维拉帕米作用2h 后,细胞摄取~(99)Tc~m-MIBI 较对照组显著增加(t=2.33,P<0.05),但 P-gp 表达水平差异无显著性(P>0.05)。(2)肿瘤细胞摄取~(99)Tc~m-MIBI 随维拉帕米作用时间的延长而增加,各时间点 UR 差异有显著性(F=58.2,P<0.05),并且,VRP 作用时间在80 min 内时,肿瘤细胞摄取~(99)Tc~m-MIBI 与 P-gp 的表达水平无相关性(r=0.16,P>0.05),VRP 作用时间大于8 h时,肿瘤细胞摄取~(99)Tc~m-MIBI 与 P-gp 的表达水平呈负相关(r=-0.73,P<0.01)。结论化疗增敏剂能够影响 P-gp 过度表达所致 MDR 肿瘤细胞对~(99)Tc~m-MIBI 的摄取。  相似文献   
26.
The aim of this retrospective study was to determine the predictors of a positive bone scan in female patients with breast carcinoma. The participants were 126 females with newly diagnosed breast carcinoma and a baseline bone scan. Patients who had started treatment before their bone scan were excluded. Bone scans were assessed as ‘no metastases’ or ‘definite skeletal metastases’ without knowledge of the patient's predictor variables. Those with ‘possible metastases’ were correlated with other available imaging and clinical information, and recategorized as ‘no metastases’ or ‘definite skeletal metastases’. Results were compared with predictor variables. Significant predictors were increasing age, a higher histopathological grading and positive progesterone receptor status following a forward-stepwise logistic regression analysis. Axillary nodal status, tumour size and oestrogen receptor status did not correlate with a positive bone scan. Not every patient needs a staging bone scan. This study is important because it predicts the need for baseline scintigraphy for specific patients in whom skeletal metastases are more likely to be present or to develop. The findings are particularly valuable in times of worldwide resource scarcity and evolving surgical practice.  相似文献   
27.
目的 探讨99mTc-tetrofosmin(99mTc-TF)平面显像、断层显像诊断乳腺癌的临床价值,并与超声检查做比较.方法 50例女性受检者均行99mTc-TF平面显像、断层显像及超声检查.以病理结果为金标准,探讨并比较99mTc-TF平面显像、断层显像及超声检查在乳腺癌良恶性鉴别诊断中的价值.结果 99mTc-TF平面、断层显像和超声检查诊断乳腺癌的灵敏度分别为74.2%、93.5%、87.1%,特异性为66.7%、73.3%、80%.结论 99mTc-TF显像尤其是断层显像是一种新的有效诊断乳腺癌的方法,可与超声检查相媲美.  相似文献   
28.
[99mTc‐EDDA–HYNIC‐D‐Phe1,Tyr3]octreotide (99mTc‐EDDA/HYNIC–TOC) is a promising new agent with the potential to replace [111In‐DTPA‐D‐Phe1]‐octreotide in somatostatin receptor scintigraphy. This hydrazinonicotinic acid derivatized somatostatin complex contains ethylenediamine N,N′ diacetic acid (EDDA) as a coligand resulting in a high in vitro and in vivo stability. Since direct 99mTc‐labelling of HYNIC–TOC with EDDA results in low labelling yields, in this study we describe the preparation of 99mTc‐EDDA/HYNIC‐TOC via coligand exchange from Tricine for EDDA. Exchange of coligands is achieved at elevated temperature and under optimized conditions of pH, EDDA concentration and stannous ion. High labelling yields (mean 95.9%) were achieved at high specific activities (>37GBq/µmol). Characterization via HPLC, receptor binding and LC–MS of the resulting complex is described. The formulation developed enables rapid and simple labelling of 99mTc‐EDDA/HYNIC–TOC in a manner suitable for a clinical setting. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
29.
Objective Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon emission computed tomography (SPECT) of ischemic heart disease. Methods Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will be followed for 3 years, stratified by patients’ clinical background and SPECT findings. Results A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2 ± 0.4 years, mean ± SEM) and 261 women (age 67.8 ± 0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension (82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis, and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%), and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received 99mTc-tetrofosmin at an initial dosage of 200–300 MBq (mean 331 ± 3 MBq) followed by a second dosage of 700–800 MBq (mean 748 ± 8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were used by the largest number (83.2%), followed by hypotensive (66.7%), hypolipidemic (40.7%), and antiplatelet drugs (27.7%), vasodilators (5.5%), and antioxidants and others (2.3%). Conclusions This study was designed to clarify the correlation between coronary artery disease and diabetes mellitus as its risk factor based on the clinical and imaging findings. Patient enrollment was closed on September 30, 2005, and follow-up is now under way.  相似文献   
30.
目的 药物负荷核素心肌显像在冠心病诊断中的价值。方法 选取本院胸痛可疑冠心病,且能耐受平板运动试验的住院患者55例,进行多巴酚丁胺(DBA)负荷99m^Tc-MIBI门控心肌灌注断层显像(SPECT),平板运动试验检查,部分行冠脉造影检查。结果DBA-SPECT结果40%(22/55)的患者DBA负荷SPECT结果呈可逆性放射性稀疏(即心肌缺血改变)。20例有冠脉造影对照的患者中,DBA负荷SPECT诊断冠心病的灵敏度87.5%(7/8),特异性75%(9/12),准确率80%(16/20)。结论DBA负荷SPECT是诊断冠心病的一种敏感性及特异性较高的非创伤性方法。  相似文献   
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