全文获取类型
收费全文 | 122021篇 |
免费 | 11910篇 |
国内免费 | 9499篇 |
专业分类
耳鼻咽喉 | 924篇 |
儿科学 | 1307篇 |
妇产科学 | 1346篇 |
基础医学 | 14095篇 |
口腔科学 | 2277篇 |
临床医学 | 17209篇 |
内科学 | 17897篇 |
皮肤病学 | 1029篇 |
神经病学 | 6549篇 |
特种医学 | 4236篇 |
外国民族医学 | 70篇 |
外科学 | 11727篇 |
综合类 | 21134篇 |
现状与发展 | 28篇 |
一般理论 | 15篇 |
预防医学 | 8172篇 |
眼科学 | 3909篇 |
药学 | 12975篇 |
125篇 | |
中国医学 | 7831篇 |
肿瘤学 | 10575篇 |
出版年
2024年 | 469篇 |
2023年 | 2057篇 |
2022年 | 5671篇 |
2021年 | 6920篇 |
2020年 | 5293篇 |
2019年 | 4280篇 |
2018年 | 4575篇 |
2017年 | 4018篇 |
2016年 | 3833篇 |
2015年 | 5848篇 |
2014年 | 7232篇 |
2013年 | 6302篇 |
2012年 | 9149篇 |
2011年 | 10299篇 |
2010年 | 6458篇 |
2009年 | 5121篇 |
2008年 | 6444篇 |
2007年 | 6197篇 |
2006年 | 6307篇 |
2005年 | 6001篇 |
2004年 | 3794篇 |
2003年 | 3559篇 |
2002年 | 3015篇 |
2001年 | 2583篇 |
2000年 | 2686篇 |
1999年 | 2760篇 |
1998年 | 1842篇 |
1997年 | 1751篇 |
1996年 | 1435篇 |
1995年 | 1338篇 |
1994年 | 1125篇 |
1993年 | 695篇 |
1992年 | 806篇 |
1991年 | 667篇 |
1990年 | 584篇 |
1989年 | 527篇 |
1988年 | 460篇 |
1987年 | 404篇 |
1986年 | 319篇 |
1985年 | 247篇 |
1984年 | 107篇 |
1983年 | 72篇 |
1982年 | 53篇 |
1981年 | 52篇 |
1980年 | 31篇 |
1979年 | 32篇 |
1978年 | 2篇 |
1964年 | 2篇 |
1962年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
Research has shown that increasing numbers of teenagers are going online to find health information, but it is unclear whether there are disparities in the prevalence of online health seeking among young Internet users associated with social and economic conditions. Existing literature on Internet uses by adults indicates that low income, less educated, and minority individuals are less likely to be online health seekers. Based on the analysis of data from the Pew Internet and American Life Project for the US, this study finds that teens of low education parents are either as likely as or even more likely than teens of high education parents to seek online health information. Multiple regression analysis shows that the higher engagement in health seeking by teens of low education parents is related to a lower prevalence of parental Internet use, suggesting that some of these teens may be seeking online health information on behalf of their low education parents. Implications of these findings are discussed in relation to the issues of the digital divide and digital empowerment. 相似文献
22.
Yulu Miao Mingxia Zhang Yulin Nie Wan Zhao Bin Huang Zhengming Jiang Shaoxiong Yu Zhibin Huang Hongjin Fu 《中国神经再生研究》2007,2(2):126-128
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections. 相似文献
23.
新型纳米根管充填材料对成骨细胞生长的影响 总被引:2,自引:0,他引:2
通过体外培养的成骨细胞,采用二甲基噻唑二苯基四唑溴盐比色法和流式细胞术对新型纳米根管充填材料(nHA-PA66)作用下的成骨细胞生长情况的变化进行研究,评价其对成骨细胞生长的影响。以该材料的细胞培养基浸提液作用于实验组细胞,对照组采用培养基本身。实验组和对照组成骨细胞的生长情况和细胞周期无显著性差异,表明该新型纳米材料对成骨细胞的生长和细胞周期无不良影响。提示新型纳米根管充填材料的成骨细胞相容性较好,具有用作根充材料的基础。 相似文献
24.
青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究 总被引:1,自引:0,他引:1
将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5~4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。 相似文献
25.
淋巴瘤样肉芽肿与韦格内肉芽肿临床特点的比较 总被引:2,自引:0,他引:2
目的 总结淋巴瘤样肉芽肿病(lym phom atoid granulom atosis,LG)与韦格内肉芽肿( egener granulo Wm atosis,W G)的临床特点,从临床上加以鉴别。 方法 回顾性总结我院与北京协和医院 1989 年以来收治的 6 例 LG和20 例 W G 患者的临床资料,并进行比较。 结果 发热、咳嗽及呼吸困难在 LG 中较常见,流涕、鼻衄及关节痛以W G 为多,肺受累以 LG 为多,耳鼻喉、眼及肾病变在 W G 中明显增多,皮肤受损两者相似。W G 患者常有 c-ANCA 阳性及尿沉渣异常。 LG X 线胸片为双侧多发结节,边界不清,多无肺门、纵隔淋巴结肿大; G 则为双侧多发边界清晰W的结节, 易形成空洞, 肺门和纵隔淋巴结可肿大。LG 病理改变为血管中心性淋巴增生性病变, 浸润的细胞主要是小淋巴细胞和不同数量大的不典型淋巴细胞; 而在 W G 中可见坏死性血管炎及大量中性白细胞、浆细胞及少量嗜酸细胞浸润形成的肉芽肿, 部分有多核巨细胞。W G 经治疗后, 多数患者病情缓解; 则疗效不佳。 结论 LG 和 W G 在临 LG床表现、实验室检查、 影像及病理诸方面的差异有利于两者的鉴别诊断。 相似文献
26.
随着人力资源的社会化和资源配置市场化的形成,人才流动成为现实和可能,人才已成为一种商品、一种资源、一种无形资本,如人才一旦另择良木而牺,将会大大削弱医院竞争的优势。为此,我们对部分三级医院中的护理人力资源管理中存在的两大危机即人员流失危机和人员梯队危机(临时聘用护士占护理人员总数的50%左右)进行分析,从重视育才、用才、留才及内部员工的安定就业、维护品质着手,采取了行之有效的措施,取得了显著的效果。 相似文献
27.
硬膜外穿刺针外套管在腹腔镜小儿斜疝高位结扎术中的应用 总被引:3,自引:0,他引:3
目的探讨硬膜外穿刺针外套管在腹腔镜小儿斜疝疝囊高位结扎中的应用价值。方法2003年4月-2006年5月,我院对230例小儿斜疝手术应用硬膜外穿刺针外套管代替雪橇钩针实施腹腔镜疝内环口荷包高位结扎术。结果230例手术均获得成功,手术时间:单侧161例8-10 min,嵌顿疝39例15-20 min,双侧30例16-20 min;术后未见有阴囊水肿及睾血疼痛及缺血坏死。术后随访2-6个月111例,6-12个月52例,12-24个月37例,24-36个月30例,无复发。结论硬膜外刺针外套管可替代小儿疝囊结扎专用的雪橇钩针,简便,经济,适合在所有基层医院推广。 相似文献
28.
X Dong M He X Song B Lu Y Yang S Zhang N Zhao L Zhou Y Li X Zhu R Hu 《Diabetic medicine》2007,24(12):1482-1486
AIMS: Our aim was to assess performances of the Cockcroft-Gault and simplified Modification of Diet in Renal Disease (MDRD) formulae in estimating glomerular filtration rate (GFR) in Chinese diabetic populations and their association with vascular risks. METHODS: A total of 1009 patients with Type 2 diabetes were categorized into low estimated GFR groups (GFR < 60 ml/min/1.73 m(2)) and control groups by the two equations. The performances of these formulae were assessed at different stages of kidney function. Carotid artery intima-media thickness (IMT) and the prevalence of diabetic retinopathy or albuminuria were compared among the groups. The ability of these formulae to identify established vascular risk markers using sensitivity, specificity, positive and negative predictive values were also compared. RESULTS: The prevalence of low estimated GFR was 32.7% with the Cockcroft-Gault formula and 5.2% with the MDRD formula, respectively. In low estimated GFR subjects by the MDRD formula, IMT was significantly thicker than those by the Cockcroft-Gault formula (1.2 mm vs. 1.0 mm; P < 0.05), with a higher prevalence of albuminuria (78.4 vs. 52.8%, P < 0.05) and diabetic retinopathy (46.5 vs. 30.5%; P < 0.05). The Cockcroft-Gault formula gave a specificity of 71.7% and a sensitivity of 37.0%, and the MDRD formula gave a specificity of 96.6% and a sensitivity of 7.9% in estimating low GFR relevant for established vascular risks. CONCLUSIONS: These formulae performed differently in Chinese diabetic populations. The simplified MDRD formula is minimally superior to the Cockcroft-Gault formula for its high specificity and positive predictive values in estimating low GFR relevant for vascular risks. 相似文献
29.
Yan Zhao 《Zhonghua yi shi za zhi (Beijing, China : 1980)》2005,35(1):229-232
There was a preliminary recognition on mumps during the Qin-Han to Sui-Tang dynasty, laying a foundation for the scholastic development on this topic in later generations. The title of this disease was identified in Song-Jin-Yuan dynasty with gradual deepening on its principle-method-formula-medication system, a great progress of recognition as compared with the previous ages. In the Ming-Qing dynasty, the recognition became even more systematic, with certain breakthrough in the system of principle-method-formula-medication. In modern age, the experiences were inherited and developed to integrate to modern biomedicine, so that the theory and clinical practice become even more perfect. 相似文献
30.
目的建立检测外周血单个核细胞α干扰素受体1(IFNAR1)及检测诱导表达α干扰素(IFN-α)的方法,评价慢性丙型肝炎患者外周血单个核细胞(PBMC)细胞免疫功能与α干扰素治疗的关系。方法Poly IC体外刺激正常对照组和慢性丙型肝炎病毒(HCV)感染组患者PBMC,利用病毒保护试验研究干扰素治疗前后患者PBMC表达的干扰素抗病毒生物学活性差异;IFN-α治疗前后,RT-PCR检测慢性丙型肝炎患者不同干扰素应答组患者PBMC IFNAR1表达的变化。结果对照组PBMC分泌的干扰素活性显著高于慢性丙型肝炎患者应答组患者(P<0.001);干扰素应答组患者PBMC分泌的干扰素活性随治疗时间延长而增加,治疗1个月后显著高于无应答组患者PBMC分泌的干扰素活性(P<0.01),后者始终处于低下水平;IFN-α治疗期间干扰素应答组患者PBMC IFNAR1水平从治疗前的高表达而逐渐减少,正常对照和干扰素无应答组患者PBMC IFNAR1的表达始终较低。结论慢性HCV感染患者的细胞免疫功能受损,不能正常表达IFN-α,但应答组患者经干扰素治疗后IFN-α表达能力逐渐恢复;干扰素无应答组患者PBMC IFNAR1表达受到严重抑制;慢性丙型肝炎患者PBMCIFN-α活性检测及IFNAR1检测结果也许可以作为干扰素治疗预后的判断指标。 相似文献