全文获取类型
收费全文 | 219705篇 |
免费 | 20736篇 |
国内免费 | 15468篇 |
专业分类
耳鼻咽喉 | 1903篇 |
儿科学 | 2231篇 |
妇产科学 | 2980篇 |
基础医学 | 26553篇 |
口腔科学 | 3710篇 |
临床医学 | 30856篇 |
内科学 | 33010篇 |
皮肤病学 | 2227篇 |
神经病学 | 12391篇 |
特种医学 | 8319篇 |
外国民族医学 | 138篇 |
外科学 | 21731篇 |
综合类 | 35400篇 |
现状与发展 | 55篇 |
一般理论 | 19篇 |
预防医学 | 13157篇 |
眼科学 | 6695篇 |
药学 | 22729篇 |
194篇 | |
中国医学 | 12350篇 |
肿瘤学 | 19261篇 |
出版年
2024年 | 692篇 |
2023年 | 3551篇 |
2022年 | 9177篇 |
2021年 | 11499篇 |
2020年 | 8595篇 |
2019年 | 7541篇 |
2018年 | 8035篇 |
2017年 | 7089篇 |
2016年 | 6658篇 |
2015年 | 10253篇 |
2014年 | 12552篇 |
2013年 | 10697篇 |
2012年 | 16008篇 |
2011年 | 17952篇 |
2010年 | 10520篇 |
2009年 | 8192篇 |
2008年 | 11119篇 |
2007年 | 11113篇 |
2006年 | 11233篇 |
2005年 | 11327篇 |
2004年 | 7001篇 |
2003年 | 6618篇 |
2002年 | 5511篇 |
2001年 | 4949篇 |
2000年 | 5356篇 |
1999年 | 5695篇 |
1998年 | 3550篇 |
1997年 | 3523篇 |
1996年 | 2836篇 |
1995年 | 2624篇 |
1994年 | 2160篇 |
1993年 | 1384篇 |
1992年 | 1892篇 |
1991年 | 1598篇 |
1990年 | 1301篇 |
1989年 | 1106篇 |
1988年 | 1030篇 |
1987年 | 902篇 |
1986年 | 737篇 |
1985年 | 541篇 |
1984年 | 340篇 |
1983年 | 249篇 |
1982年 | 157篇 |
1981年 | 153篇 |
1980年 | 116篇 |
1979年 | 142篇 |
1978年 | 56篇 |
1977年 | 57篇 |
1975年 | 64篇 |
1974年 | 56篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
941.
低剂量电离辐射对小鼠免疫器官cAMP和儿茶酚胺含量的影响 总被引:2,自引:0,他引:2
本文报道,75mGy/(12.5mGy/min)单次全身X射线照射后9小时用SRBC免疫C57BL/6小鼠,在免疫后4天和7天脾脏、胸腺和下丘脑cAMP含量均降低;而在免疫后4天脾脏去甲肾上腺素、肾上腺素和酪氨酸含量均增高,免疫后7天肾上腺素含量仍持续增高;当连接γ射线65mGy(0.015mGy/min,6h/d)全身照射小鼠后即刻或29小时后免疫,脾脏和下丘脑cAMP含量也均降低。提示,低剂量 相似文献
942.
Traditional Chinese Medicine was adopted in the treatment of 216 cases (219 eyes) of retinal vein occlusion. The period of treatment averaged 3 months; the total rate of efficacy was 80.4%. During an average follow-up of 3 years, 84.1% of the patients maintained a stable or slightly improved vision. The authors believed that treatment of the disease with TCM promoted the absorption of blood and formation of collateral circulation, and suppressed neovascularization, thus preventing repeated bleeding that would lead to serious complications. 相似文献
943.
944.
P. C. Avila H. A. Boushey H. Wong H. Grundland J. Liu J. V. Fahy 《Clinical and experimental allergy》2004,34(1):77-84
BACKGROUND : Selectins participate in the initial phase of leucocyte migration from circulation to inflamed tissues and may play a role in inflammatory cellular influx into airways in asthma. In the sheep asthma model, TBC1269, a pan-selectin antagonist, reduced late allergen response by 74%. OBJECTIVE : To determine whether a single dose of TBC1269 inhibits early (EAR) and late (LAR) asthmatic responses, and whether it inhibits sputum leucocyte influx after inhalation allergen challenge in atopic asthmatic subjects treated with bronchodilators only. METHODS : Twenty-one asthmatic subjects (mean+/-SD, age=32.5+/-6.7 years, 8 males, FEV1 percent predicted=84+/-15%) with known late asthmatic response based on a screening inhalation allergen challenge were randomly assigned to receive intravenous treatment with either placebo (n=11) or TBC1269 (n=10, 30 mg/kg) infused over 15 min immediately prior to a second (post-treatment) allergen challenge at least 4 weeks after the screening challenge. After each challenge, EAR and LAR were monitored for 7 h. In addition, sputum was induced 1 day before and 1 day after each allergen challenge. RESULTS : TBC1269 did not attenuate the EAR compared with placebo (largest fall in FEV1 within 1 h of 34.1+/-13.9% vs. 31.8+/-12.2% for TBC1269 and placebo groups respectively, P=0.61) or the LAR (largest fall in FEV1 between 3 and 7 h of 39.3+/-15.3% vs. 32.6+/-13.8%, P=0.24). TBC1269 had only minor effects on allergen-induced sputum eosinophilia. CONCLUSION : We conclude that TBC1269 administered before allergen challenge as a single intravenous dose does not attenuate early or late asthmatic responses to allergen in asthmatic subjects. 相似文献
945.
946.
老年人颅脑外伤后缺血性脑卒中发作特点及治疗 总被引:1,自引:1,他引:0
目的探讨老年人颅脑外伤后缺血性脑卒中发作特点及个性化治疗方案。方法针对7例颅脑外伤后急性期出现缺血性脑血管病症状的老年患者,通过脑血管造影检查分析其发病原因并根据不同的脑血管特点决定治疗方案。结果大多数患者(6/7)受伤前已存在不同程度的颅内外血管狭窄、血管壁溃疡以及附壁血栓形成等改变,提示脑缺血发作主要与这些病变为基础的脑血流下降、血栓脱落等因素密切相关。而外伤后脑灌注降低、脑血管痉挛是脑缺血发作的诱发因素。结论老年人外伤后的缺血性脑卒中发作主要与原有的脑血管基础疾病有关,预防和治疗老年人外伤后缺血性脑卒中发作,应基于这些病变特征并选择个体化治疗方案。 相似文献
947.
目的:分析新生儿医院感染相关危险因素及干预对策.方法:通过对榆林市第一医院2006年5月至2010年5月收治的1428例住院新生儿医院感染发生情况.结果:新生儿患者医院感染率从2006年5月至2008年5月的3.20%,下降到2008年5月至2010年5月的1.99%.结论:对新生儿室医疗护理工作中各种医院感染相关危险因素采取相应的干预对策后,新生儿患者的医院感染率明显降低,提高了医疗护理质量. 相似文献
948.
大肠癌肝转移射频消融后局部复发影响因素的分析 总被引:1,自引:0,他引:1
目的 探讨射频消融(radiofrequency ablation,RFA)治疗大肠癌肝转移后局部肿瘤复发的风险因素。方法 回顾性研究213例347个肿瘤实施RFA治疗后局部复发的临床资料,对可能影响RFA局部治疗效果的临床因素进行统计学处理。结果 175例(82.2%)298个肿瘤(85.9%)得到CT或MRI随访资料。大肠癌肝转移灶RFA后肿瘤局部复发率为36.9%(110/298),局部复发的平均时间为16.4月(2~57个月)。单因素分析显示肝脏转移灶的部位、大小和射频针类型与肿瘤射频后的局部复发相关(P值分别为P=0.000,P=0.021和P=0.026),但Cox多因素分析则显示只有瘤大小和转移灶部位是大肠癌肝转移射频消融后局部复发的独立预后因素(χ^2=8.522,P=0.000;χ^2=1.321,P=0.022)。结论 肝脏肿瘤的大小和部位是RFA治疗效果的独立影响因素,正确的电极选择和布针是获得肿瘤完全坏死的关键。 相似文献
949.
950.
Yueh-Wei Liu Allan M Concejero Chao-Long Chen Yu-Fan Cheng Hock-Liew Eng Tung-Liang Huang Tai-Yi Chen Chih-Chi Wang Shih-Ho Wang Chih-Che Lin Chee-Chien Yong Chin-Hsiang Yang Amornetta P Jordan Bruno Jawan 《Liver transplantation》2007,13(11):1545-1551
A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children. 相似文献