全文获取类型
收费全文 | 7797篇 |
免费 | 777篇 |
国内免费 | 449篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 48篇 |
妇产科学 | 28篇 |
基础医学 | 379篇 |
口腔科学 | 84篇 |
临床医学 | 311篇 |
内科学 | 779篇 |
皮肤病学 | 79篇 |
神经病学 | 75篇 |
特种医学 | 96篇 |
外国民族医学 | 1篇 |
外科学 | 237篇 |
综合类 | 1356篇 |
预防医学 | 343篇 |
眼科学 | 16篇 |
药学 | 2688篇 |
9篇 | |
中国医学 | 2428篇 |
肿瘤学 | 47篇 |
出版年
2024年 | 48篇 |
2023年 | 104篇 |
2022年 | 387篇 |
2021年 | 470篇 |
2020年 | 306篇 |
2019年 | 237篇 |
2018年 | 237篇 |
2017年 | 320篇 |
2016年 | 348篇 |
2015年 | 362篇 |
2014年 | 737篇 |
2013年 | 655篇 |
2012年 | 593篇 |
2011年 | 638篇 |
2010年 | 416篇 |
2009年 | 362篇 |
2008年 | 332篇 |
2007年 | 367篇 |
2006年 | 303篇 |
2005年 | 259篇 |
2004年 | 214篇 |
2003年 | 194篇 |
2002年 | 159篇 |
2001年 | 141篇 |
2000年 | 101篇 |
1999年 | 74篇 |
1998年 | 73篇 |
1997年 | 63篇 |
1996年 | 59篇 |
1995年 | 47篇 |
1994年 | 50篇 |
1993年 | 47篇 |
1992年 | 32篇 |
1991年 | 24篇 |
1990年 | 23篇 |
1989年 | 21篇 |
1988年 | 31篇 |
1987年 | 18篇 |
1986年 | 27篇 |
1985年 | 22篇 |
1984年 | 13篇 |
1983年 | 18篇 |
1982年 | 11篇 |
1981年 | 17篇 |
1980年 | 16篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1970年 | 5篇 |
排序方式: 共有9023条查询结果,搜索用时 15 毫秒
1.
陈振华 《中国卫生标准管理》2020,(8):76-79
目的探讨儿童流感应用帕拉米韦注射液治疗的临床疗效以及用药安全性。方法随机选定在2016年1月-2019年1月期间佛山市高明区人民医院儿科住院治疗并确诊流感A或B型患儿200例,通过随机数字法将其分为治疗组和对照组。治疗组100例用帕拉米韦注射液治疗,对照组100例用国产磷酸奥司他韦颗粒治疗,评价两组患儿治疗前后症状评分、治疗效果、治疗指标以及不良反应发生情况。结果两组患儿治疗前流感样症状评分无统计学意义(P>0.05),两组患儿治疗后较治疗前流感样症状评分均下降,差异有统计学意义(P<0.05);治疗组治疗后流感样症状评分略小于对照组,但是无统计学意义(P>0.05);治疗组治疗总有效率高于对照组,治疗组患儿发热症状缓解、全部症状缓解以及住院时间均小于对照组,存在统计学意义(P<0.05)。治疗组与对照组不良反应发生率较低,且无统计学意义(P>0.05)。结论帕拉米韦注射液可用于儿童流感治疗,不仅能够保证临床疗效,而且可加快症状缓解,同时存在较高用药安全性。 相似文献
2.
Solid-state reactions between sodium hydride and sodium hydroxide are unusual among hydride-hydroxide systems since hydrogen can be stored reversibly. In order to understand the relationship between hydrogen uptake/release properties and phase/structure evolution, the dehydrogenation and hydrogenation behavior of the Na-O-H system has been investigated in detail both ex- and in-situ. Simultaneous thermogravimetric-differential thermal analysis coupled to mass spectrometry (TG-DTA-MS) experiments of NaH-NaOH composites reveal two principal features: Firstly, an H2 desorption event occurring between 240 and 380 °C and secondly an additional endothermic process at around 170 °C with no associated weight change. In-situ high-resolution synchrotron powder X-ray diffraction showed that NaOH appears to form a solid solution with NaH yielding a new cubic complex hydride phase below 200 °C. The Na-H-OH phase persists up to the maximum temperature of the in-situ diffraction experiment shortly before dehydrogenation occurs. The present work suggests that not only is the inter-phase synergic interaction of protic hydrogen (in NaOH) and hydridic hydrogen (in NaH) important in the dehydrogenation mechanism, but that also an intra-phase Hδ+… Hδ– interaction may be a crucial step in the desorption process. 相似文献
3.
目的观察补脾泻肝法治疗腹泻型肠易激综合征的临床疗效。方法100例腹泻型肠易激综合征患者随机分为2组,治疗组60例给予白术芍药散加味,对照组40例给予丙咪嗪合替加色罗治疗。2组均4周为1个疗程,观察疗效,并于3-6个月后观察2组病例复发情况。结果治疗组治愈率为65%,总有效率为85%,6个月内复发率为20%,对照组则分别为32.5%、72.5%、55.56%,2组比较差异均有统计学意义(均P<0.05)。结论补脾泻肝法治疗腹泻型肠易激综合征优于丙咪嗪合替加色罗,疗效确切。 相似文献
4.
Simultaneous Quantification of an Enantiomer and the Racemic Compound of Ibuprofen by X-ray Powder Diffractometry 总被引:1,自引:0,他引:1
Purpose. An X-ray powder diffractometric method was developed for the simultaneous quantification of the relative amounts of the racemic compound (±) of ibuprofen (I) and S(+)-ibuprofen (II), when they occur as a mixture.
Methods. The X-ray powder diffraction patterns of I and II show pronounced differences. This formed the basis for the determination of the relative amounts of I and II when they occur as a mixture. X-ray lines with d-spacings of 14.41 and 4.37 Å were unique to I and II, respectively. Mixtures containing different proportions of I and II were prepared which also contained lithium fluoride (III) as an internal standard.
Results. A linear relationship was obtained when the intensity ratio (intensity of the 4.37 Å line of II/intensity of the 2.01 Å line of III) was plotted as a function of the weight fraction of II in the mixture. Similar results were obtained in the case of I. Using these standard curves, the weight fractions of I and II in 'unknown' mixtures were determined. The experimentally determined analyte concentration ranged between 98 and 104% of the true value. The relative error in the analyses of individual samples was < 10%. The minimum detectable weight fraction of I in II and II in I were 0.032 (3.2% w/w) and 0.034 (3.4% w/w), respectively. The minimum quantifiable weight fractions were 0.136 for I and 0.112 for II. Since the X-ray diffraction patterns of S(+)-ibuprofen and R(–)-ibuprofen are identical, the conclusions drawn regarding mixtures of I and II will also hold true in the quantitative analyses of mixtures of I and R(–)-ibuprofen. 相似文献
5.
6.
强化婴幼儿奶粉中叶酸的测定 总被引:1,自引:0,他引:1
强化叶酸的奶粉在0.05M K_2HPO_4缓冲液中,经均质,调pH4.5,15000g离心20分钟,其清液调pH4.0,进行CGS树脂离子交换层析,用10ml KClK_2HPO_4洗脱,调pH7.0,进行HPLC测定,采用300x3.9mm ODS反相柱,移动相0.05M K_2HPO+MeOH(91+9),流速1ml/分,紫外检测器波长285nm,灵敏度0.0050D。方法相对标准偏差为±3.3%,回收率为87%,最小检测量为0.02μg/ml。 相似文献
7.
热力学计算表明,H2,N2的过量有助于提高TiN的产率,但能耗也相应增加。为此考察了温度,流量,TiCl4携带量,混合方式对产物性能的影响。结果表明,流量增加,温度升高,TiCl4携带量增加,混合愈好,则产物粒径愈小。在此基础上采用微波等离子体化学气相沉积法,合成了粒径为123-284nm的TiN超细颗粒 相似文献
8.
In this study breast tissue that contained ultrastructural dense core granules has been examined from 24 patients. The possible neuroendocrine characteristics of the granules were studied using the uranaffin reaction and an ultrastructural argyrophil stain. The tissue included 15 breast carcinomas and nine benign samples. Two types of breast dense core granules can be distinguished on the basis of intracellular distribution patterns and histochemical reactivity. Type I dense core granules are the most common and they were found subluminally distributed in non-pathological tissues and benign lesions as well as carcinomas. They were uranaffin-negative and are unlikely to be of endocrine nature. Type II dense core granules were found only in four carcinomas, where they occurred abundantly throughout the cytoplasm. These granules were uranaffin-positive and argyrophilic and thus exhibited characteristics consistent with neuroendocrine structure. 相似文献
9.
10.
本文运用模糊数学原理,对东台市1993年7月份市面上的全脂乳粉抽查监测结果进行卫生质量综合评价,结果令人满意,从而为乳粉卫生质量评比建立了客观有效的评价模型。 相似文献