全文获取类型
收费全文 | 400篇 |
免费 | 15篇 |
国内免费 | 9篇 |
专业分类
儿科学 | 14篇 |
基础医学 | 12篇 |
临床医学 | 40篇 |
内科学 | 6篇 |
皮肤病学 | 4篇 |
神经病学 | 3篇 |
外科学 | 24篇 |
综合类 | 72篇 |
预防医学 | 148篇 |
眼科学 | 2篇 |
药学 | 40篇 |
中国医学 | 56篇 |
肿瘤学 | 3篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 7篇 |
2021年 | 6篇 |
2020年 | 12篇 |
2019年 | 19篇 |
2018年 | 11篇 |
2017年 | 4篇 |
2016年 | 1篇 |
2015年 | 6篇 |
2014年 | 19篇 |
2013年 | 31篇 |
2012年 | 32篇 |
2011年 | 28篇 |
2010年 | 27篇 |
2009年 | 23篇 |
2008年 | 19篇 |
2007年 | 26篇 |
2006年 | 18篇 |
2005年 | 11篇 |
2004年 | 17篇 |
2003年 | 19篇 |
2002年 | 11篇 |
2001年 | 16篇 |
2000年 | 8篇 |
1999年 | 12篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
排序方式: 共有424条查询结果,搜索用时 15 毫秒
151.
152.
重组DNA、痘苗病毒载体(VV)作为人类免疫缺陷症病毒(HIV)抗原的送递系统因其能同时诱导细胞免疫和体液免疫而受到重视,作者对表达HIV包膜(Env)蛋白的DNA和VV载体(DNA-Env和VV-Env)及纯化的Env蛋白的免疫效果进行了检测。 将HIV-ⅢB株的 gp140 Env编码序列插入含有巨细胞病毒增强子/启动子的质粒中,用基因枪将包被于金粒上的重组质粒注入8~12周龄的C57BL/6小鼠腹部;或腹腔接种表达 HIV-ⅢB株蛋白的重组 VV感染细胞的裂解物;纯化蛋白疫苗则由gp 120(1… 相似文献
153.
Objective To observe the effect of methylprednisolone (MP) pre-intervention on ex-pressions of heat shock protein 27 (HSP27) and tumor necrosis factor alpha (TNF-α) in cells in rat spinal cord following ischemia-reperfusion injury. Methods One hundred and fifty male Sprague-Dawley (SD) rats were randomly divided into 3 equal groups: group A (control) in which the abdominal aorta was exposed without any treatment, group B in which the abdominal aorta was clipped for 30 minutes before reperfusion for 3 bours to establish a model of ischemia- reperfusion injury, and group C in which intravenous MP injection was conducted 30 minutes before the establishment of the ischemia-reperfusion injury model. Three hours later the spinal cords were harvested. Pathological changes of spinal cord cells were observed with HE staining and expressions of HSP27 and TNF-α in spinal cord cells were observed with immunohistochemical staining. The motor function of hind-limbs before was evaluated before sample harvest. The data were analyzed with SPSS software. Results There were significant differences between groups A and B in the expressions of TNF-α and HSP27. Compared with group B, the expression of TNF-α decreased and HSP27 increased in group C, with statistically significant differences between the 2 groups. The motor function score of hind-limbs decreased in group B but improved in group C. Conclusions Since MP can decrease the expression of TNF-α and up-regulate the expression of HSP27, it has a potency of neuro-protection. Spinal cord ischemia-reperfusion injury can be avoided or decreased after MP pre-intervention. 相似文献
154.
Objective To observe the effect of methylprednisolone (MP) pre-intervention on ex-pressions of heat shock protein 27 (HSP27) and tumor necrosis factor alpha (TNF-α) in cells in rat spinal cord following ischemia-reperfusion injury. Methods One hundred and fifty male Sprague-Dawley (SD) rats were randomly divided into 3 equal groups: group A (control) in which the abdominal aorta was exposed without any treatment, group B in which the abdominal aorta was clipped for 30 minutes before reperfusion for 3 bours to establish a model of ischemia- reperfusion injury, and group C in which intravenous MP injection was conducted 30 minutes before the establishment of the ischemia-reperfusion injury model. Three hours later the spinal cords were harvested. Pathological changes of spinal cord cells were observed with HE staining and expressions of HSP27 and TNF-α in spinal cord cells were observed with immunohistochemical staining. The motor function of hind-limbs before was evaluated before sample harvest. The data were analyzed with SPSS software. Results There were significant differences between groups A and B in the expressions of TNF-α and HSP27. Compared with group B, the expression of TNF-α decreased and HSP27 increased in group C, with statistically significant differences between the 2 groups. The motor function score of hind-limbs decreased in group B but improved in group C. Conclusions Since MP can decrease the expression of TNF-α and up-regulate the expression of HSP27, it has a potency of neuro-protection. Spinal cord ischemia-reperfusion injury can be avoided or decreased after MP pre-intervention. 相似文献
155.
156.
157.
Objective To observe the effect of methylprednisolone (MP) pre-intervention on ex-pressions of heat shock protein 27 (HSP27) and tumor necrosis factor alpha (TNF-α) in cells in rat spinal cord following ischemia-reperfusion injury. Methods One hundred and fifty male Sprague-Dawley (SD) rats were randomly divided into 3 equal groups: group A (control) in which the abdominal aorta was exposed without any treatment, group B in which the abdominal aorta was clipped for 30 minutes before reperfusion for 3 bours to establish a model of ischemia- reperfusion injury, and group C in which intravenous MP injection was conducted 30 minutes before the establishment of the ischemia-reperfusion injury model. Three hours later the spinal cords were harvested. Pathological changes of spinal cord cells were observed with HE staining and expressions of HSP27 and TNF-α in spinal cord cells were observed with immunohistochemical staining. The motor function of hind-limbs before was evaluated before sample harvest. The data were analyzed with SPSS software. Results There were significant differences between groups A and B in the expressions of TNF-α and HSP27. Compared with group B, the expression of TNF-α decreased and HSP27 increased in group C, with statistically significant differences between the 2 groups. The motor function score of hind-limbs decreased in group B but improved in group C. Conclusions Since MP can decrease the expression of TNF-α and up-regulate the expression of HSP27, it has a potency of neuro-protection. Spinal cord ischemia-reperfusion injury can be avoided or decreased after MP pre-intervention. 相似文献
158.
广州市1992~1995年学生常见病调查分析 总被引:6,自引:3,他引:3
目的:根据全国学生常见病综合防治中期考评方案的要求,对广州市12个区和县级市1992~1995年学生常见病情况进行调查分析。方法:采用按不同学习阶段分层整群随机抽样方法。结果:蛔虫感染率各区、县均有下降,但不平衡;沙眼患病率明显下降,并与健康行为形成率呈正相关;营养不良与肥胖均表现为城区高于县级市,营养不良为中学生高于小学生,肥胖为小学生高于中学生;视力低下表现为城区高于县级市,且随学龄递升而增高。结论:4年间广州市学生常见病的防治工作取得一定成绩,除视力低下和肥胖外,各病均有不同程度的下降。 相似文献
159.
目的评价AC群脑膜炎球菌(结合)b型流感嗜血杆菌(结合)联合疫苗(MenAC-Hib)上市后预防接种不良事件发生率。方法采用多中心、无对照、Ⅳ临床试验设计招募2-71月龄儿童,按照基础免疫程序接种MenAC-Hib,收集每剂次接种后0-30d不良事件和全程免疫后6个月内严重不良事件;分析不良事件发生率。结果受试者共接种MenAC-Hib 17116剂次,发生不良事件2099例,总发生率为12.26%。1、2、3、4级不良事件发生率分别为8.62%、6.34%、0.95%、0.01%。全身、局部不良反应发生率分别为10.93%、0.65%;全身反应主要为发热、腹泻、皮疹、烦躁,发生率分别为9.49%、1.60%、0.80%、0.73%;局部反应主要为注射部位硬结、红、肿胀,发生率分别为0.31%、0.24%、0.15%。结论2-71月龄儿童接种MenAC-Hib后不良事件发生率在预期范围内,以轻微反应为主而严重反应罕见。 相似文献
160.
东北铁线莲中皂苷类化学成分研究 总被引:1,自引:0,他引:1
目的研究东北铁线莲Clematis manshurica的化学成分。方法采用硅胶柱色谱、凝胶色谱及高压制备色谱等方法对东北铁线莲的三萜皂苷类成分进行分离纯化,并通过其理化性质及波谱数据对分离得到的化合物进行结构表征。结果从东北铁线莲中共分离得到10个齐墩果烷型三萜皂苷类化合物,分别鉴定为威灵仙皂苷L(1)、clematichinenosideA(2)、clematochinenoside F(3)、clematernoside A(4)、clematichinenoside B(5)、clematichinenoside C(6)、clematomandshurica saponin B(7)、clematomandshurica saponin D(8)、clematomandshurica saponin C(9)、huzhangoside B(10)。结论化合物1为新的三萜皂苷类化合物,2~6为首次从该植物中分离得到。 相似文献