全文获取类型
收费全文 | 6066篇 |
免费 | 372篇 |
国内免费 | 207篇 |
专业分类
耳鼻咽喉 | 59篇 |
儿科学 | 50篇 |
妇产科学 | 75篇 |
基础医学 | 1094篇 |
口腔科学 | 249篇 |
临床医学 | 446篇 |
内科学 | 579篇 |
皮肤病学 | 191篇 |
神经病学 | 512篇 |
特种医学 | 150篇 |
外国民族医学 | 3篇 |
外科学 | 607篇 |
综合类 | 1003篇 |
预防医学 | 209篇 |
眼科学 | 312篇 |
药学 | 584篇 |
8篇 | |
中国医学 | 140篇 |
肿瘤学 | 374篇 |
出版年
2024年 | 9篇 |
2023年 | 72篇 |
2022年 | 148篇 |
2021年 | 182篇 |
2020年 | 211篇 |
2019年 | 136篇 |
2018年 | 144篇 |
2017年 | 165篇 |
2016年 | 193篇 |
2015年 | 160篇 |
2014年 | 305篇 |
2013年 | 397篇 |
2012年 | 293篇 |
2011年 | 340篇 |
2010年 | 308篇 |
2009年 | 247篇 |
2008年 | 280篇 |
2007年 | 254篇 |
2006年 | 231篇 |
2005年 | 229篇 |
2004年 | 202篇 |
2003年 | 204篇 |
2002年 | 170篇 |
2001年 | 156篇 |
2000年 | 121篇 |
1999年 | 101篇 |
1998年 | 108篇 |
1997年 | 103篇 |
1996年 | 109篇 |
1995年 | 123篇 |
1994年 | 98篇 |
1993年 | 92篇 |
1992年 | 84篇 |
1991年 | 74篇 |
1990年 | 62篇 |
1989年 | 67篇 |
1988年 | 72篇 |
1987年 | 66篇 |
1986年 | 50篇 |
1985年 | 67篇 |
1984年 | 38篇 |
1983年 | 40篇 |
1982年 | 24篇 |
1981年 | 26篇 |
1980年 | 19篇 |
1979年 | 13篇 |
1978年 | 14篇 |
1977年 | 16篇 |
1976年 | 8篇 |
1974年 | 5篇 |
排序方式: 共有6645条查询结果,搜索用时 406 毫秒
1.
《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes. 相似文献
2.
张献彩 《山西医科大学学报》2015,(1)
目的:观察糖尿病小鼠小肠绒毛杯状细胞分泌的黏原颗粒是否改变,为进一步研究糖尿病的消化系统并发症提供形态学基础。方法分别选取3,5,8,10月龄db/db糖尿病小鼠及相应年龄段的db/+m正常小鼠,每组6只,标本用4%多聚甲醛灌流固定后,从距Treitz韧带约10 cm处切下一段空肠,用PAS染色方法对小肠杯状细胞分泌的黏原颗粒进行观察。结果糖尿病组小肠绒毛易被破坏,糖尿病组中杯状细胞的分泌物比同月份正常对照组显著增加(P<0.05);糖尿病组中3月龄的杯状细胞分泌物最多,8月龄最少,并且8月龄分别与3月龄、5月龄比较均存在着显著差异(P<0.05);正常对照组随月龄增长无显著性差异(P>0.05)。结论糖尿病时杯状细胞分泌物增多可能对小肠绒毛有保护作用。 相似文献
3.
谷志宏 《中国继续医学教育》2020,(7):88-90
目的探讨布拉氏酵母菌散治疗对新生儿高胆红素血症的临床疗效。方法在2018年1月—2019年1月期间,将医院诊治的110例新生儿高胆红素血症患儿纳入研究对象,按照治疗方法的不同,将患儿分成两组,采用常规蓝光照射治疗的患儿定为对照组,55例,在蓝光治疗基础上增加布拉氏酵母菌散治疗的患儿定为观察组,55例,对比两组患儿治疗的临床效果。结果观察组和对照组治疗的有效率分别为98.18%和87.27%,有统计学意义(P<0.05);治疗后3 d和1周,两组患儿的胆红素水平明显下降,且观察组患儿下降更加明显,与对照组相比差异有统计学意义(P<0.05);观察组患儿黄疸消退时间为(5.12±1.21)d,对照组患儿黄疸消退时间为(7.21±1.22)d,有统计学意义(P<0.05);观察组不良反应发生率为5.45%,明显低于对照组的12.73%,有统计学意义(P<0.05)。结论对新生儿高胆红素血症患儿在常规蓝光治疗的基础上增加布拉氏酵母菌散进行治疗,可以显著提高临床治疗效果。 相似文献
4.
Joshua Manghelli Lisa Brown Hany B. Tadros Nabil A. Munfakh 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(5):491-494
The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery. 相似文献
5.
目的观察亚甲蓝甘油合剂封闭治疗三叉神经痛的临床疗效并探讨其治疗机制。方法按国际头面痛学会分类委员会确定的诊断标准,108例原发性三叉神经患者随机分为两组:A组为亚甲蓝甘油合剂组(n=54),B组为单纯甘油合剂组(n=54);采用徐贵印推荐的三维测角穿刺半月神经节进行封闭治疗,对治疗后1周、3个月和2年分别进行疗效评判和随访观察。结果两组治疗后1周、3个月优良率比较差异无统计学意义(P>0.05),两年后优良率比较差异有统计学意义(P<0.05);两组并发症没有明显差异,2例出现视力下降,3例因解剖变异未能穿刺成功,仅在卵圆孔周围进行了注射,外加眶下孔以及骸孔封闭。结论亚甲蓝甘油合剂用于治疗三叉神经痛远期疗效优于单纯甘油合剂,且亚甲蓝对神经未见明显损害(经2年随访)。 相似文献
6.
T. M. Skerry M.D. M.R.C.V.S. R. Suswillo A. J. El Haj N. N. Ali R. A. Dodds L. E. Lanyon 《Calcified tissue international》1990,46(5):318-326
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent
loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further
loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the
effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations
related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we
use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent
loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation
occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue
after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation
produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores,
bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix. 相似文献
7.
P16INK4、PCNA在肺癌中表达的研究 总被引:3,自引:0,他引:3
目的 通过检测肺癌组织中p16、PCNA的表达,探讨其在肺癌发生发展中的作用及相互关系。方法 采用S—P免疫组化方法,检测83例肺癌标本及15例正常肺组织标本中P16^INK4和PCNA的表达。结果 P16^INK4和PCNA在正常肺组织和肺癌组织中表达的阳性率存在显著性差异。P16^INK4表达的阳性率在小细胞癌与非小细胞癌之间有显著性差异。PNTM分期高的肺癌标本P16^INK4及PCNA表达阳性率显著高于分期低的肺癌标本。不同分化程度的肺癌组织P16^INK4及PCNA表达阳性率有显著性差异。结论 肺癌的发生与P16^INK4的低表达和PCNA的高表达有关。而P16^INK4的表达与肺癌的组织学类型、分化程度、临床分期有关;PCNA的表达与肺癌的分化程度、临床分期有关。 相似文献
8.
双J管临床应用及美蓝在置管术中的作用 总被引:1,自引:0,他引:1
目的探讨双J管(双J输尿管支架管)在泌尿系疾病治疗中的应用效果以及美蓝在置放术中的作用。方法对215例患者采用放置双J管作内支架和内引流治疗,近期48例术中以美蓝协助定位。结果术后留置尿管5~7d,无切口感染、尿瘘等并发症。术后1~3个月拔除双J管,随访3~6个月,肾功能、肾积水明显好转,吻合口通畅。以美蓝协助定位者无双J管上移致拔管困难。结论双J管具有内支架和内引流作用,操作简单,引流效果好,并发症少,缩短住院时间。以美蓝协助定位,值得推广应用。 相似文献
9.
Sheri Thompson-Henry M.A. C.C.C.-S.L.P. Barbara Braddock M.H.S. C.C.C.-S.L.P. 《Dysphagia》1995,10(3):172-174
The modified Evan's blue dye procedure (MEBD) is a method of performing tracheal suctioning of the patient through the tracheostomy tube after administration of color-contrasted food and liquid. The MEBD is done when radiographic or fiberoptic procedures are not available or practical. In 5 tracheostomized patients, the MEBD does not detect aspiration. 相似文献
10.
L Peichl 《The Journal of comparative neurology》1992,324(4):590-602
The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat. 相似文献