全文获取类型
收费全文 | 1314篇 |
免费 | 91篇 |
国内免费 | 162篇 |
专业分类
儿科学 | 5篇 |
基础医学 | 68篇 |
口腔科学 | 5篇 |
临床医学 | 45篇 |
内科学 | 52篇 |
皮肤病学 | 11篇 |
神经病学 | 10篇 |
特种医学 | 17篇 |
外科学 | 19篇 |
综合类 | 262篇 |
预防医学 | 17篇 |
眼科学 | 7篇 |
药学 | 500篇 |
2篇 | |
中国医学 | 533篇 |
肿瘤学 | 14篇 |
出版年
2024年 | 4篇 |
2023年 | 18篇 |
2022年 | 32篇 |
2021年 | 39篇 |
2020年 | 43篇 |
2019年 | 40篇 |
2018年 | 49篇 |
2017年 | 66篇 |
2016年 | 67篇 |
2015年 | 52篇 |
2014年 | 112篇 |
2013年 | 141篇 |
2012年 | 96篇 |
2011年 | 102篇 |
2010年 | 64篇 |
2009年 | 65篇 |
2008年 | 71篇 |
2007年 | 53篇 |
2006年 | 60篇 |
2005年 | 44篇 |
2004年 | 22篇 |
2003年 | 37篇 |
2002年 | 28篇 |
2001年 | 30篇 |
2000年 | 19篇 |
1999年 | 26篇 |
1998年 | 8篇 |
1997年 | 10篇 |
1996年 | 12篇 |
1995年 | 6篇 |
1994年 | 22篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1971年 | 3篇 |
排序方式: 共有1567条查询结果,搜索用时 15 毫秒
21.
Bladder cancer is the second most prevalent malignancy in the genitourinary tract and remains a therapeutic challenge. In the search for new treatments, researchers have attempted to find compounds with low toxicity. With this goal in mind, Uncaria tomentosa is noteworthy because the bark and root of this species are widely used in traditional medicine and in adjuvant therapy for the treatment of numerous diseases. The objective of this study was to investigate the antitumor effect of one purified bioactive fraction of U. tomentosa bark on cell proliferation in two human bladder cancer cell lines, T24 and RT4. Quinovic acid glycosides purified fraction (QAPF) of U. tomentosa decreased the growth and viability of both T24 and RT4 cell lines. In T24 cells, QAPF induced apoptosis by activating caspase-3 and NF-κB. Further study showed that this fraction does not induce cell cycle arrest and does not alter PTEN and ERK levels. In conclusion, we demonstrated that QAPF of U. tomentosa has a potent inhibitory effect on the growth of human bladder cancer cell lines by inducing apoptosis through modulation of NF-κB, and we suggest that QAPF may become a potential therapeutic agent for the prevention and/or treatment of this cancer. 相似文献
22.
Xiu-Ying Chen Chao Gu Min Ma Qing Cong Ting Guo Duan Ma Bin Li 《International journal of clinical and experimental pathology》2014,7(1):144-151
Premature ovarian insufficiency (POI) is a main cause of infertility and affects nearly 1% women under 40 years old. This study was aimed to utilize the side effects of tripterygium glycoside (TG) to induce a mouse model of POI. 48 female KM mice were divided into four groups: control, oral, intraperitoneal injection and subcutaneous injection group. The mice in last three groups were treated with TG (50 mg•kg-1) daily for 35 days, while the mice in control group were treated with parallel volume of sterile water. Vaginal smears were taken to monitor the estrous cycles and estrous frequency for the last 21 days. Ovarian and uterine index and histomorphological change were determined when finished the administration. Serum levels of FSH were assessed by ELISA. Ki-67 expression in the uterus was analyzed from using immunohistochemical detection. And the apoptosis of follicle cells were detected by TUNEL assay. The results showed that mice in subcutaneous injection group presented the critical manifestations with significantly prolonged estrous cycles, decreased estrous frequency, reduced ovarian and uterine index, and increased serum FSH levels. At this dose level, TG could reduce developing follicles and corpus luteum, and increase atretic follicles, which might be induced by the increasing levels of follicle apoptosis. The proliferation index of uterus, evaluated by histomorphological changes and the expression of Ki-67, was significantly suppressed in TG treated animals. These data suggested that TG was feasible to induce a mice model via subcutaneous injection which could mimic the manifestations of POI. 相似文献
23.
目的:观察山茱萸总苷(TGCO)对大鼠实验性变态反应性脑脊髓炎(EAE)的影响。方法:Wistar大鼠24只随机分为3组:正常对照组、EAE组和TGCO组。采用动物行为学、常规苏木精-伊红染色和LFB髓鞘染色观察大鼠的发病情况与中枢神经系统(CNS)的病理变化。结果:EAE组7/8只大鼠出现典型的EAE行为学改变、CNS炎性细胞浸润和髓鞘脱失。TGCO组有3,8只大鼠出现EAE行为学改变,评分最高为29,潜伏期延长,CNS内炎性细胞浸润和髓鞘脱失明显减轻。对照组未见动物行为学和CNS病理学改变。结论:TGCO能减轻EAE大鼠的临床症状、延长潜伏期和降低发病率。 相似文献
24.
Katherine M. Weh Yun Zhang Connor L. Howard Amy B. Howell Jennifer L. Clarke Laura A. Kresty 《Nutrients》2022,14(5)
Esophageal adenocarcinoma (EAC) is a cancer characterized by rapidly rising incidence and poor survival, resulting in the need for new prevention and treatment options. We utilized two cranberry polyphenol extracts, one proanthocyanidin enriched (C-PAC) and a combination of anthocyanins, flavonoids, and glycosides (AFG) to assess inhibitory mechanisms utilizing premalignant Barrett’s esophagus (BE) and EAC derived cell lines. We employed reverse phase protein arrays (RPPA) and Western blots to examine cancer-associated pathways and specific signaling cascades modulated by C-PAC or AFG. Viability results show that C-PAC is more potent than AFG at inducing cell death in BE and EAC cell lines. Based on the RPPA results, C-PAC significantly modulated 37 and 69 proteins in JH-EsoAd1 (JHAD1) and OE19 EAC cells, respectively. AFG treatment significantly altered 49 proteins in both JHAD1 and OE19 cells. Bioinformatic analysis of RPPA results revealed many previously unidentified pathways as modulated by cranberry polyphenols including NOTCH signaling, immune response, and epithelial to mesenchymal transition. Collectively, these results provide new insight regarding mechanisms by which cranberry polyphenols exert cancer inhibitory effects targeting EAC, with implications for potential use of cranberry constituents as cancer preventive agents. 相似文献
25.
目的 探讨雷公藤多苷联合泼尼松治疗IgA肾病的临床效果及其对尿Smad2和TGF-β1的影响.方法 选取于福建医科大学附属泉州第一医院就诊的IgA肾病患者共155例,随机分为3组,分别为雷公藤多苷组51例、泼尼松组52例和联合组52例,其中雷公藤多苷组失访1例,泼尼松组因严重感染退出研究2例,联合组因严重感染退出研究2... 相似文献
26.
The cytochemical distribution of Na-K-ATPase was demonstrated in the guinea-pig myocardium. The hearts were fixed with paraformaldehyde glutaraldehyde mixture, sections were incubated at room temperature in modified Ernst medium employing p-nitrophenyl phosphate as substrate and the tissue was processed for electron microscopy. The ATPase activity was localized in the subsarcolemmal cisterns, inner side of plasma membrane, T-tubules, free and junctional sarcoplasmic reticulum and capillary endothelium. The reaction product on the plasma membrane and T-tubules was inhibited by ouabain or by potassium deletion. However, the amount of precipitation in mitochondria, sarcoplasmic reticulum (free and junctional) and subsarcolemmal cisterns remained unaffected by ouabain or by potassium deletion. The enzyme reaction in the myocardium represents ouabain-sensitive, potassium-dependent ATPase. 相似文献
27.
28.
29.
目的:探讨肉苁蓉总苷( GCs)对阿尔茨海默病(AD)模型大鼠学习认知功能的影响及其作用机制。方法:
双侧脑室注射Aβ1-42 制备AD大鼠模型,连续给予模型大鼠不同剂量的GCs 腹腔注射20 d,Morris 水迷宫检测各
组大鼠空间学习记忆能力,尼氏染色观察海马CA1区细胞形态并计数正常锥体细胞;免疫组织化学测定脑组织突
触素( SYN)含量、酶联免疫吸附试验测定血清超氧化物歧化酶( SOD)和谷胱甘肽过氧化物酶( GSH-Px)活
性、丙二醛( MDA)的含量。结果:GCs 可明显缩短逃避潜伏期与上台前路程,明显增加目标象限时间百分比
与穿越平台次数;GCs 能提高海马CA1区锥体细胞的存活率,明显增加SYN蛋白的表达和提高SOD、GSH-Px 活
性,降低MDA的活性。结论:GCs 改善AD学习认知障碍的机制可能是通过减少自由基堆积、清除体内过多的
过氧化物,进而提高突触可塑性来改善学习认知功能。 相似文献
30.
目的观察宝乐果(Borojo)提取物8,9-糖基化环烯醚萜苷(GIG)对体外培养的人骨关节炎软骨细胞促进增殖和抑制细胞凋亡的作用。方法体外培养人骨关节炎软骨细胞,进行软骨细胞鉴定。用不同浓度(25、50、100、200、400μg/ml)的8,9-糖基化环烯醚萜苷培养人骨关节炎软骨细胞,用硫酸酚嗪甲酯(MTS)法、5-乙炔基-2脱氧尿嘧啶核苷(EdU)法、平板克隆形成实验检测细胞的增殖、流式细胞术观察软骨细胞凋亡,用丙二醛(MDA)法、超氧化物歧化酶(SOD)检测、谷胱甘肽过氧化物酶(GSH-Px)检测观察软骨细胞氧化酶的活性,用Western bolt法检测凋亡相关蛋白表达。结果与对照组相比,随GIG浓度增加,细胞活力升高,差异有统计学意义(P<0.01);细胞核分裂增加,差异有统计学意义(P<0.05);细胞克隆数量增多,差异有统计学意义(P<0.05);细胞周期的S期延长,细胞增殖活跃细胞凋亡率减少;MDA含量下降,差异有统计学意义(P<0.05)。SOD含量升高,差异有统计学意义(P<0.05);GSH-Px含量升高,差异有统计学意义(P<0.05)。结论 GIG可能对软骨细胞具有增殖的作用,而且在观察浓度内,细胞毒性小,并可抑制细胞凋亡,提示其有潜在能力可能成为治疗骨关节炎的一种策略。 相似文献