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151.
Evidence is increasing suggesting that adding progestogens to estrogens can increase the risk of breast cancer. However, our experimental data as a result of scientific collaboration between university of Tuebingen, Germany, and university of Beijing, China, comparing all available progestogens used in hormone therapy and hormonal contraception present high evidence that there may be differences regarding breast cancer risk. Especially of concern may be to differentiate between primary and secondary risk i.e. between the effect of on benign and malignant breast epithelial cells suggesting differences in primary risk and risk in patients after breast cancer. Of importance also is that in contrast to natural progesterone the apocrine impact of stromal growth factors and also certain cell components of breast epithelial cells can strongly increase proliferation rates of some (but not all. synthetic progestogens which can lead to clinical cancer before (in contrast to estrogen-only therapy. carcinoprotective mechanisms can work. Regarding clinical data, epidemiological studies and especially the Women's Health Initiative, so far the only prospective placebo-controlled study, demonstrate an increased risk under combined estrogen/progestogen-, but not under estrogen-only therapy. However, up to now the clinical studies cannot discriminate between the various progestogens mostly due to too small patient numbers in the subgroups, and in most studies either medroxyprogesterone acetate or norethisterone have been used. However, there is evidence that the natural progesterone and dydrogesterone, possibly also the transdermal usage of synthetic progestogens, may have less risks, but this must be proven in further clinical trials. 相似文献
152.
Rong-Hua Yang Ju-Lin Xie Bin Shu Xu-Sheng Liu Xiao-Dong Chen Shu-Bin Ruan Shao-Hai Qi 《International journal of clinical and experimental pathology》2013,6(11):2529-2534
The management of burns and injuries using novel treatment strategies involving epidermal stem cells (ESC) requires a better understanding of the biology of these cells, in particular, their isolation and the maintenance of their unique characteristics in culture. The purpose of this study was to describe an improved method for isolating putative ESC from fetal rat skin and to maintain them long term in culture. Single ESC suspensions were obtained from fetal rat skin by enzyme digestion containing 0.5% neutral protease. The target cells were harvested by rapid adherence on type IV collagen plates and were cultured in complex DMEM. After primary isolation, cells were continuously cultured in K-serum free medium. After reaching 70-80% confluence, the cells were digested with 0.25% trypsin at 37°C for 5-10 minutes, and passaged at a ratio of 1:2. The cultured ESC showed good growth, resulting in cell viability of over 98%. Four days later, clones containing 100-200 cells were detected, showing cobblestone-like characteristics. The rapidly adherent cells were positive for keratin 15, 19 and P63. Eighty three percent of cells expressed β1 integrin. The growth-curve showed that the rapidly adherent cells were in the exponential growth phase. The protocol described in this paper provides a simplified and effective method to isolate and maintain long-term culture of epidermal stem cells from fetal rat skin. This method should be valuable for isolating and studying ESC from various transgenic rat lines that are currently available. 相似文献
153.
目的采用数字图像相关法动态研究LED光固化灯不同光照强度对光固化复合树脂聚合收缩的影响。方法收集12颗大小接近的新鲜离体磨牙,随机分为3组,制备大小为2.0 mm×2.0 mm×2.0mm的邻(?)面洞形,洞面酸蚀冲洗后涂粘接剂光照10 s,充填3M Z350纳米复合树脂,邻面快速制造散斑,LED固化灯垂直(?)面光照40s,3组光照强度分别为300 mW/cm~2、500 mW/cm~2和800 mW/cm~2,数码相机同步实时采集光照过程中试件表面散斑的变化序列图像,用数字图像相关法计算获得各序列图上逐个像素点水平方向(x)和垂直方向(y)位移,统计线性收缩率,描绘各像素点的时域变化曲线,并用SPSS 12.01统计软件包进行方差分析和配对t检验。结果 3种光照强度下树脂x方向线收缩率分别为0.081%~0.486%、0.004%~0.316%和0.063%~0.560%,y方向线收缩率分别为0.088%~0.981%、0.003%~0.77%和0.157%~1.252%,3组之间差异有统计学意义(P<0.05);3组第20 s树脂游离面收缩x方向位移差异无统计学意义,y方向位移差异有统计学意义。结论 LED光固化灯500 mW/cm~2光照时引起的树脂聚合收缩最小。 相似文献
154.
目的了解在校大学生的口腔保健意识和饮食习惯,为完善口腔健康教育提供原始数据,探讨更优化的教育模式。方法采用分层抽样的方法,对四川大学1 500名大学生以问卷调查的形式对其口腔保健意识和饮食习惯进行调查。结果大学生主要为保持口气清新而刷牙,甜食食用频率主要为每周1~2次,数量集中在100~400 g,女生食用甜食的频率显著高于男生,而男生饮用饮料的频率和量更高,食用甜食后多数学生不做清洁措施,大多数学生在牙疼或变色时不会及时就诊,仅当疼痛难忍时才就医。结论大学生的口腔保健行为缺乏,食用甜食频率数量较高,就诊意识淡薄,学校等机构应该加强口腔保健知识的宣传和教育来提高大学生自我口腔保健意识。 相似文献
155.
Papadopoulos N Martin J Ruan Q Rafique A Rosconi MP Shi E Pyles EA Yancopoulos GD Stahl N Wiegand SJ 《Angiogenesis》2012,15(2):171-185
Pharmacological inhibition of VEGF-A has proven to be effective in inhibiting angiogenesis and vascular leak associated with
cancers and various eye diseases. However, little information is currently available on the binding kinetics and relative
biological activity of various VEGF inhibitors. Therefore, we have evaluated the binding kinetics of two anti-VEGF antibodies,
ranibizumab and bevacizumab, and VEGF Trap (also known as aflibercept), a novel type of soluble decoy receptor, with substantially
higher affinity than conventional soluble VEGF receptors. VEGF Trap bound to all isoforms of human VEGF-A tested with subpicomolar
affinity. Ranibizumab and bevacizumab also bound human VEGF-A, but with markedly lower affinity. The association rate for
VEGF Trap binding to VEGF-A was orders of magnitude faster than that measured for bevacizumab and ranibizumab. Similarly,
in cell-based bioassays, VEGF Trap inhibited the activation of VEGFR1 and VEGFR2, as well as VEGF-A induced calcium mobilization
and migration in human endothelial cells more potently than ranibizumab or bevacizumab. Only VEGF Trap bound human PlGF and
VEGF-B, and inhibited VEGFR1 activation and HUVEC migration induced by PlGF. These data differentiate VEGF Trap from ranibizumab
and bevacizumab in terms of its markedly higher affinity for VEGF-A, as well as its ability to bind VEGF-B and PlGF. 相似文献
156.
157.
目的:探讨吉西他滨联合奥沙利铂经肝动脉化疗栓塞(transcatheter arterial chemoembolization,TACE)在防治肝癌高危患者术后复发中的价值.方法:回顾性分析肝癌术后复发高危患者120例,88例术后3-6wk接受TACE治疗为TACE组,其中43例采用吉西他滨联合奥沙利铂组成的GEMOX方案(GEMOX组),45例使用传统化疗药物方案(对照组);32例因其他原因未接受TACE治疗作为为单纯手术组.通过6mo、12mo的随访,比较各组6mo、12mo术后复发率.结果:TACE组术后6mo、12mo肝内复发率(20.5%、43.8%)明显低于单纯手术组(37.5%、59.4%),两者均有统计学意义(χ2=6.512、4.573,P<0.05).在TACE组中,GEMOX组6mo术后复发率(11.6%)较对照组(28.9%)低,差异有统计学意义(χ2=4.026,P<0.05),两组12mo术后复发率无明显差异(χ2=0.876,P>0.05);在TACE不良反应中,GEMOX组白细胞减少及恶心、呕吐发生率较对照组低,差异有统计学意义(Z=-2.156、-2.295,P<0.05).结论:对肝癌术后复发高危患者进行预防性TACE有助于减少或延缓术后近期复发率,吉西他滨联合奥沙利铂方案疗效更佳. 相似文献
158.
159.
目的提高扁桃体手术患儿漱口依从性,促进伤口愈合。方法将111例扁桃体手术患儿随机分为实验组(54例)和对照组(57例)。均行常规护理和采用复方硼砂溶液漱口。对照组入院即用硼砂原液漱口至出院后2周;实验组采取浓度递增的方法即入院第1天用硼砂原液与蒸馏水按1∶3配制,第2天用1∶1比例配制,第3天用硼砂原液漱口至出院后2周。结果实验组住院期间及出院后1周漱口依从性显著高于对照组(P<0.05,P<0.01),伤口愈合良好率显著高于对照组(P<0.01)。擅自减药、停药及拒绝服药为主要不依从表现,家长忘记、担心药物不良反应及患儿不配合、不愿坚持为主要原因。结论对扁桃体手术患儿采取漱口液浓度递增的方法可提高患儿漱口的依从性,从而促进伤口愈合。 相似文献
160.
Thomas C. Harford Chiung M. Chen Tulshi D. Saha Sharon M. Smith W. June Ruan Bridget F. Grant 《Journal of psychiatric research》2013