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991.
Moon WK Chang KH Weinmann HJ Koh YH Im JG Yeon KM Han MC 《AJR. American journal of roentgenology》2000,174(5):1385-1390
OBJECTIVE: The objective of this study was to compare enhancement patterns of a blood-pool contrast agent, Gadomer-17, with those of gadopentetate dimeglumine in bacterial abscesses and VX2 carcinoma in rabbits. MATERIALS AND METHODS: Fourteen rabbits with experimentally induced bacterial abscesses and VX2 carcinoma in both thighs underwent dynamic contrast-enhanced MR imaging with Gadomer-17 and gadopentetate dimeglumine at a 24-hr interval. The enhancement ratios (postcontrast to precontrast signal intensities) of lesions in the same animal were assessed and correlated with microvessel density. RESULTS: For Gadomer-17, the enhancement ratio of the abscesses (1.66 +/- 0.39) peaked 15 min after the injection, while that of the carcinoma (2.05 +/- 0.16) peaked at 10 min. The enhancement ratios of the carcinoma were consistently higher than those of the abscesses up to 30 min. For gadopentetate dimeglumine, peak enhancement ratio of the abscesses (2.30 +/- 0.75) was seen 5 min after the injection, while that of the carcinoma (2.32 +/- 0.51) was seen at 3 min. The enhancement ratios of the carcinomas were significantly higher at 1 min, but significantly lower at 20-30 min, compared with those of the abscesses, as a result of rapid decrease of enhancement ratios in the carcinomas. The microvessel density was 9.8 +/- 5.2 vessels per field of view for the abscesses and 36.3 +/- 9.5 vessels per field of view for the carcinoma (p < 0.001). CONCLUSION: Delayed peak enhancement and slow decay were found in both bacterial abscess and VX2 carcinoma with Gadomer-17, whereas early peak enhancement and rapid decay were found especially in VX2 carcinoma with gadopentetate dimeglumine. Enhancement ratios on MR imaging with a blood-pool contrast agent correlated well with the microvessel density in bacterial abscess and VX2 carcinoma. 相似文献
992.
Kim SY Lee KS Han J Kim J Kim TS Choo SW Kim SJ 《AJR. American journal of roentgenology》2000,174(3):795-798
OBJECTIVE: We describe the chest CT and pathologic findings of semiinvasive pulmonary aspergillosis in six patients. CONCLUSION: Semiinvasive pulmonary aspergillosis should be considered in the mildly immunocompromised patient with CT findings that reveal persistent parenchymal abnormalities. Patterns include consolidation and mass. 相似文献
993.
目的采用分光光度法测定人RBC谷胱甘肽硫转移酶(GSTs)活性,研究196名(男101名,女95名)健康汉族人的GSTs活性分布。方法制备人RBC裂解后,参照Habdous等的方法测定GSTs活性。反应体系如下:0.1 mol.L-1磷酸钠缓冲液(pH 6.5)2.6 mL,RBC裂解液0.1 mL,30 mmol.L-1谷胱甘肽0.1 mL,10 mmol.L-11-氯-2,4-二硝基苯(CDNB)0.1 mL。结果方法的日内和日间精密度均<10%。RBC GSTs活性呈正偏态分布,196例健康汉族人的平均GSTs活性为(3.89±0.96)U.(gHb)-1。不同年龄组平均GSTs活性无差异,而女性的平均GSTs活性比男性的平均值高,但并不显著。结论确定了可供临床参考的健康汉族人GSTs活性分布范围。 相似文献
994.
结核病临床分离株及痰标本中embB基因型的快速测定 总被引:2,自引:0,他引:2
目的建立快速测定结核病耐乙胺丁醇(EMB)分离株和痰标本中结核分枝杆菌EMB耐药基因型的方法,以期为患者提供及时、有效地化验结果。方法应用16S rDNA聚合酶链反应(PCR)-单链构象多态性(SSCP)和PCR-限制性片段长度多态性(RFLP)对11株耐EMB分离株和46例结核病痰标本进行分子菌种鉴定和embB基因突变的部位与性质分析。结果以结核分枝杆菌H37Rv标准株为对照,11株耐EMB分离株和46例临床痰标本经16S rDNA PCR-SSCP分析电泳图谱均与结核分枝杆菌标准株相同;限制性内切酶NlaⅢ消化embB基因扩增产物显示,11株耐EMB分离株中4株(36.4%)不被NlaⅡ消化;46例结核病痰标本中10例(21.7%)不被NlaⅡ消化。结论部分结核分枝杆菌耐EMB是由于embB基因突变所致。采用PCR-SSCP和PCR-RFLP方法可直接快速测定结核病耐EMB分离株和痰标本中结核分枝杆菌耐EMB基因型。 相似文献
995.
Takayasu's arteritis: assessment of disease activity with contrast-enhanced MR imaging 总被引:2,自引:0,他引:2
Choe YH Han BK Koh EM Kim DK Do YS Lee WR 《AJR. American journal of roentgenology》2000,175(2):505-511
OBJECTIVE: The purpose of this study was to evaluate the role of contrast-enhanced MR imaging in the determination of disease activity in patients with Takayasu's arteritis. SUBJECTS AND METHODS: High-resolution contrast-enhanced T1-weighted spinecho MR imaging using small fields of view (14-20 cm) and thin slices (4-5 mm) was performed in 26 patients with Takayasu's arteritis and 16 healthy subjects. The degree of aortic mural enhancement was assessed by measuring signal intensity and by visually estimating it in comparison with that of the myocardium. RESULTS: Contrast-enhanced MR imaging showed more enhancement of thickened aortic wall compared with myocardium, thus suggesting active Takayasu's arteritis on MR imaging in 16 patients. Determination of disease activity using contrast-enhanced MR imaging was concordant with clinical findings in 23 patients (88.5%). Contrast-enhanced MR findings were concordant with laboratory findings in most patients (erythrocyte sedimentation rate in 92.3% [24/26] and C-reactive protein in 84.6% [22/26]). The measured signal intensity of the aortic wall relative to that of myocardium during the early phase of contrast-enhanced MR imaging correlated well with the erythrocyte sedimentation rate (r = 0.78, p < 0.005) and with the C-reactive protein level (r = 0.63, p < 0.005). CONCLUSION: Contrast-enhanced MR imaging provides information about disease activity of Takayasu's arteritis, which may be useful in the diagnosis and treatment of Takayasu's arteritis. 相似文献
996.
目的了解本地区近5年小儿血液系统感染的常见病原菌及抗菌药物的敏感性情况,以便指导临床医师合理使用抗生素。方法将小儿血液系统分离出的836株病原菌应用K-B法做了9种抗菌药物敏感性测定,并对不同年度的革兰氏阳性菌和革兰氏阴性菌的敏感率进行了分析。结果革兰氏阳性球菌(金黄色葡萄球菌、微球菌、表皮葡萄球菌)对丁胺卡那霉素和先锋5号的敏感率为76.8%和74.7%。革兰氏阴性杆菌(大肠埃希氏菌、伤寒沙门氏菌、非发酵菌)对丁胺卡那霉素和先锋5号的敏感率为82.4%和74.3%。铜绿假单胞菌对氧哌嗪青霉素的敏感率为89.0%,伤寒沙门氏菌对氯霉素、卡那霉素和氟哌酸的敏感率也很高,分别为88.4%,93.3%和83.1%。革兰氏阳性球菌对青霉素、红霉素、氨苄青霉素的耐药率很高分别为83.6%,82.7%,76.5%。大肠埃希氏菌对链霉素、氨苄青霉素、氯霉素和羧苄青霉素的耐药率也很高,分别为82.4%,99.4%,95.0%和80.0%。结论加强对儿科医师合理使用抗生素知识的培训、指导和评价是必要的。 相似文献
997.
998.
999.
目的探讨YAG激光与药物联合治疗文唇后接触性唇炎的疗效。方法随机选取130例文唇后接触性唇炎患者,应用美国Coherent公司生产的多功能多波长皮肤美容激光器(Nd:YAG激光)进行治疗,联合应用抗组胺药物等内服以及皮质类固醇激素外用。结果130例患者,完全治愈112例(占86.2%),显效16例(占12.3%),有效2例(占1.5%),无效为0,总有效率100%。结论YAG激光与药物结合治疗文唇后接触性唇炎获得满意疗效,具有创伤小,疗效高,副作用少,不留疤痕等特点。 相似文献
1000.