全文获取类型
收费全文 | 7055篇 |
免费 | 1918篇 |
国内免费 | 170篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 233篇 |
妇产科学 | 64篇 |
基础医学 | 2017篇 |
口腔科学 | 212篇 |
临床医学 | 596篇 |
内科学 | 811篇 |
皮肤病学 | 119篇 |
神经病学 | 687篇 |
特种医学 | 64篇 |
外科学 | 942篇 |
综合类 | 731篇 |
现状与发展 | 1篇 |
预防医学 | 460篇 |
眼科学 | 92篇 |
药学 | 671篇 |
中国医学 | 255篇 |
肿瘤学 | 1157篇 |
出版年
2024年 | 102篇 |
2023年 | 201篇 |
2022年 | 282篇 |
2021年 | 296篇 |
2020年 | 282篇 |
2019年 | 711篇 |
2018年 | 1174篇 |
2017年 | 223篇 |
2016年 | 245篇 |
2015年 | 274篇 |
2014年 | 534篇 |
2013年 | 548篇 |
2012年 | 312篇 |
2011年 | 314篇 |
2010年 | 229篇 |
2009年 | 207篇 |
2008年 | 163篇 |
2007年 | 110篇 |
2006年 | 94篇 |
2005年 | 269篇 |
2004年 | 103篇 |
2003年 | 56篇 |
2002年 | 69篇 |
2001年 | 40篇 |
2000年 | 257篇 |
1999年 | 244篇 |
1998年 | 271篇 |
1997年 | 134篇 |
1996年 | 121篇 |
1995年 | 63篇 |
1994年 | 128篇 |
1993年 | 155篇 |
1992年 | 231篇 |
1991年 | 58篇 |
1990年 | 148篇 |
1989年 | 35篇 |
1988年 | 116篇 |
1987年 | 76篇 |
1986年 | 54篇 |
1985年 | 50篇 |
1984年 | 47篇 |
1983年 | 20篇 |
1982年 | 39篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1977年 | 4篇 |
1976年 | 11篇 |
1974年 | 11篇 |
1971年 | 4篇 |
排序方式: 共有9143条查询结果,搜索用时 0 毫秒
51.
[目的] 观察膜肾1号方对膜性肾病大鼠肾脏病理的改善作用及其对自噬通路磷脂肌醇3-激酶(PI3K)/蛋白激酶B(AKT)/雷帕霉素靶蛋白(mTOR)相关蛋白表达的影响。[方法] 将大鼠随机分为对照组、模型组、膜肾1号方高剂量组、中剂量组、低剂量组,盐酸贝那普利组。采用大鼠尾静脉注射阳离子化牛血清白蛋白(C-BSA)的方法建立MN大鼠模型,灌胃、取材。苏木精-伊红(HE )染色法观察大鼠肾脏组织病理改变;免疫球蛋白G(IgG)免疫荧光染色观察大鼠IgG沉积;蛋白免疫印迹法(Western Blot)检测PI3K/Akt/mTOR 信号通路相关蛋白及自噬相关蛋白轻链3(LC3)表达。[结果] 药物干预后,膜肾1号方组大鼠24 h尿蛋白、三酰甘油、总胆固醇、低密度脂蛋白下降且低于模型组,并具有统计学差异(P<0.05)。光镜下观察,HE染色示正常组肾组织整体结构基本正常,膜性肾病(MN)模型组肾小球毛细血管丛充血,系膜增生,基底膜出现增厚,部分肾小管细胞空泡变、组织内可见炎症细胞浸润,可见嗜复红蛋白及IgG沉积。经膜肾1号方和盐酸贝那普利干预后,大鼠肾脏病理学改变均有所减轻。各组大鼠IgG沉积显示,与对照组比较模型组IgG沉积明显,IgG荧光表达升高,差异具有统计学意义(P<0.05),盐酸贝那普利组和膜肾1号方组IgG荧光表达下降且低于模型组,具有统计学差异(P<0.05)。Western Blot检测显示,药物干预后,盐酸贝那普利组和膜肾1号方组大鼠PI3K-Akt信号通路相关蛋白表达下降,LC3 表达增加,并具有统计学差异(P<0.05)。[结论] 膜肾1号方可改善大鼠肾脏病理损伤,膜肾1号方干预后PI3K-Akt信号通路相关蛋白磷酸化磷酸肌醇3激酶(p-PI3K),磷酸化Akt蛋白(p-Akt),磷酸化雷帕霉素靶蛋白(p-mTOR)表达明显降低,自噬相关蛋白LC3表达升高,其分子机制与自噬信号通路的调控有关。 相似文献
52.
Baek KH 《Molecular human reproduction》2004,10(5):291-297
Recent studies indicate that a number of factors including chromosomal abnormalities, immunological feto-maternal rejection, hormonal irregulation and anatomical factors are involved in provoking recurrent pregnancy loss (RPL). This indicates that normal cellular regulation of these factors is required for maintaining normal pregnancy. In addition, it is expected that biological processes for maintaining normal pregnancy require a series of differential gene expression. As expected, our previous investigations revealed that there are >/=30 genes showing different levels of expression between normal and RPL patients. In addition, other research groups have also identified a number of genes that are expressed aberrantly in pregnancy failure. In this review, recent study on aberrant expression levels of genes, which are grouped as immunity-related, angiogenesis-related, apoptosis-related and other groups of genes, will be discussed. 相似文献
53.
Analysis of different cellular fractions after incubation of SW 948 and SW 707 colorectal carcinoma cells or WM 266-4 melanoma cells with 125I-insulin revealed the nondegraded hormone in the chromatin of these cells. Nuclear 125I-insulin was bound to specific fragments of EcoRI-, HaeIII-, and HincII-digested chromatin. A 45-kDa chromatin protein species that binds 125I-insulin was identified. Actinomycin D and cycloheximide inhibited the insulin-stimulated expression of chromatin receptors. Uptake of 125I-insulin by isolated nuclei occurred only in the presence of plasma membranes. Thus, at least some effects of insulin on target cells can be explained by direct gene regulation instead of "second messenger" action. 相似文献
54.
冷冻浓缩腹水回输在治疗顽固性肝硬化腹水中的应用 总被引:4,自引:0,他引:4
目的 探讨冷冻浓缩腹水回输治疗顽固性肝硬化腹水的疗效。方法 采用透析机对32例顽固性肝硬化腹水患者的腹水进行超滤浓缩,置-18℃环境中冷冻2~3天,37℃温育溶解后静脉回输。结果 冷冻浓缩腹水回输前后,血清总蛋白为(59.1±5.6)g/L和(66.3±4.7)g/L,白/球比值为0.8±0.3和1.1±0.5,腹水总蛋白为(15.2±6.8)g/L和(55.6±8.4)g/L;腹围为(91.3±9.5)cm和(80.8±9.2)cm,腹压为(3.5±0.43)kPa和(2.4±0.32)kPa,24 h尿量为(615.0±185.5)ml和(1 240.0±255.0)ml;治疗前后相比,差异有高度显著性(P<0.01)。血清钾为(3.5±1.1)mmol/L和(4.0±1.3)mmol/L,腹水钾(3.6±0.9)mmol/L和(4.1±1.0)mmol/L;血清钠为(122.2±4.0)mmol/L和(126.5±4.3)mmol/L,腹水钠为(120.8±4.5)mmol/L和(123.3±4.7)mmol/L;血清氯为(90.3±6.2)mmol/L和(95.1±5.7)mmol/L,腹水氯为(92.0±5.9)mmol/L和(96.4±50.5)mmol/L;治疗前后相比,血清钠、腹水钠、腹水钾、血清氯、腹水氯差异均有显著性(P<0.05,P<0.01),血清钾差异无显著性(P>0.05)。冷冻浓缩腹水回输后,除2例出现一过性发热外,未发生低血压、肝昏迷、消化道出血现象,未出现蛋白凝集、堵塞管腔;未出现电解质紊乱现象。结论 冷冻浓缩腹水回输可大量回收腹水 相似文献
55.
目的 研究 5 -氨基水杨酸 (5 ASA)的主要药效学。方法 镇痛试验采用小鼠热板法及扭体法 ;抗炎试验采用小鼠耳片法、蛋清诱导大鼠足肿胀模型。结果 5 ASA片剂 3种剂量 (75、15 0及 30 0mg·kg-1,ig× 3d)对二甲苯诱导的小鼠耳肿胀度及蛋清诱导的大鼠踝关节肿胀度均有明显抑制作用 ;以上剂量还可明显抑制小鼠扭体反应 ,大剂量还可延长小鼠热板的舔足反应潜伏期。结论 5 ASA片剂有明显的抗炎镇痛作用。 相似文献
56.
阮晓梅 《南通大学学报(哲学社会科学版)》2000,(1)
英、汉语分属两种不同的语系 ,受语言与文化特殊性的影响 ,人们对色彩的感受和赋予颜色词的意义也各不相同。翻译时 ,不可望文生义 ,“对号入座” ,必须在充分了解中西方文化差异的基础上 ,准确把握颜色词所处的语境 ,力求做到信、达、雅 相似文献
57.
Ping Gao Yinglin Lu Xueming Ge Wenhong Fan Shengfa Fu Shuang Liu Heping Yang 《中国癌症研究》1997,9(3):192-194
In order to investigate TGFβ1 gene expression and its effect on murine tumor growth following direct intratumoral injection
of naked plasmid DNA encoding human TGFβ1, LM3 murine lung adenocarcinoma cells were inoculated subcutaneously to T739 mice and grew to tumor nodules in 2 weeks. Multiple direct intratumoral injection of plasmid DNA, PMAMneo- TGFβ1, were given
and compared with saline or vector plasmid administration groups. The growth of tumor was observed till the 8th week when
the mice were killed for Northern blot analysis and histopathological study of tumoral tissue. The results showed that the
growth of tumor was boosted in the TGFβ1 gene treated mice as compared with the control groups, whereas there was no significant
difference in the metastatic behavior. Northern blot showed efficient expression of TGFβ1 mRNA in the treated group. The present
study indicated that TGFβ1 may stimulate tumor growthin vivo through certain mechanisms. And direct intra-tumoral injection of nude plasmid DNA may be a promising gene transfer strategyin vivo.
This work was supported by the National Natural Science Foundation of China (No. 39370761). 相似文献
58.
Terue Okamura Toshiko Kobashi Joji Kawabe Hironobu Ochi Yasuto Onoyama Seiji Yamagami 《Journal of bone and mineral metabolism》1994,12(Z1):S111-S116
Renal osteodystrophy (ROD) accompanied by long-term hemodialysis patients with chronic renal failure includes several forms
of disorders of mineral and skeletal metabolism such as osteitis fibrosa attributed to secondary hyperparathyroidism, osteomalasia
and adynamic bone disease. Bone scan is performed to detect of the mainly pathophysiology of ROD. We investigated bone scan
of 25 hemodialysis patients with secondary hyperparathyroidism diagnosed clinically before and after parathyroidectomy (PTX).
Before PTX an diffusely high accumulation of bone seeking agent in the whole skeleton especially skull in all patients (100%),
vertebra in 24 out of 25 (96%), patella in 24/25 (96%), limbs in 23/25 (92%), sternum in 19/25 (76%), sacrum in 18/25 (72%)
and costochondral junctions in 14/25 (56%) was noted in these patients. The radionuclide activity of the calvaria, maxilla
and mandible in the skull was prominently high. Fourteen patients had an equally high activity in the calvaria, maxilla and
mandible, 6 patients had higher activity in the maxilla and mandible than that of calvaria and 5 patients had higher in the
calvaria than that of maxilla and mandible. After PTX the changes in the skull were obvious in 19 patients who showed a more
markedly decreased in activity of the maxilla and mandible than that of the calvaria. In 3 patients showed a more markedly
decreased in activity of the calvaria than that of the maxilla and mandible. Another 3 demonstrated equally decreased in activity
in the calvaria, maxilla and mandible. It became clear that the highest activity of the skull was shown in all patients and
the therapeutic changes of the skull are the most pronounced in maxilla and mandible in this study. 相似文献
59.
程义刚 《中国卫生事业管理》1999,(1):40-41
在宣传贯彻落实《献血法》,开展公民无偿献血工作启动阶段,有许多工作要做,其中有五项是关键性的,即制定具体实施细则,建立管理机构网络,广泛宣传发动,分配献血指标和提供便利的献血条件。抓好这五个关键环节,无偿献血工作才能较好地开展下去。 相似文献
60.