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21.
SPARC is a secreted glycoprotein that plays a complex and multifaceted role in tumour formation and progression. However, whether SPARC is an oncogene or a tumour suppressor is still unclear. Moreover, SPARC demonstrates potential in clinical pancreatic adenocarcinoma (PAAD) treatment, although it has been identified as an oncogene in some studies and a tumor suppressor in others. In the present study, a pan-cancer analysis of SPARC was carried out using The Cancer genome Atlas data, which demonstrated that SPARC was an oncogene in most cancer types and a cancer suppressor in others. In addition, SPARC expression was significantly upregulated in PAAD and associated with poor prognosis. SPARC also promoted the proliferation and migration of PANC-1 and SW1990 cell lines in vitro. SPARC was detected in the culture supernatant of PAAD cells and pancreatic acinar AR42J cells. SPARC regulated PAAD cell proliferation only when secreted into the extracellular milieu, thus explaining why the prognosis of patients with PAAD is correlated with the SPARC expression of both tumour cells and stromal cells. Collectively, the present findings demonstrated that the function of SPARC was associated with tumour type and that SPARC may represent an important oncogene in PAAD that merits further study. 相似文献
22.
Lifeng Qin Jinmei Qin Xiaoping Lv Caiqiao Yin Qian'e Zhang Jiqiao Zhang 《Oncology Letters》2021,22(1)
Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world. The etiology and pathogenesis of HCC remain unclear. Macrophage migration inhibitory factor (MIF) plays a critical role in the pathogenesis of hepatocellular carcinoma. The association between MIF polymorphisms and its expression level in HCC has rarely been demonstrated. In the present study, the peripheral blood of 202 patients with HCC (HCC group), 242 patients with chronic hepatitis B (CHB group), 215 patients with liver cirrhosis (LC group) and 227 healthy volunteers (normal group) were collected, DNA was extracted and the target fragment of MIF gene was amplified using PCR. The products were then sequenced, and the expression levels of MIF protein were tested using ELISA. The results showed that the MIF rs755622 polymorphism was associated with an increased susceptibility and metastasis of HCC, and that the genotypes GC and CC were associated with poor prognosis of HCC. Compared with the normal, CHB and LC groups, the expression of MIF in the peripheral blood of the HCC group was significantly increased, and the high expression was associated with to poor prognosis. In the HCC group, MIF protein levels for genotypes GC and CC were increased compared with those of genotype GG. The current study indicated that the MIF rs755622 polymorphism is associated with susceptibility and metastasis of HCC, and that the GC and CC genotypes may be indicators of poor prognosis, which may be ascribed to the MIF rs755622 polymorphism leading to elevated MIF protein expression in peripheral blood. 相似文献
23.
Lulu Zhao Weili Han Xisheng Yang Dongbing Zhao Penghui Niu Xianchun Gao Zhenkun Wu Xiaojie Zhang Zefeng Li Gang Ji Yingtai Chen 《Cancer science》2021,112(8):3266-3277
The argument concerning the exact minimum number of examined lymph nodes (ELNs) has continued for a long time among various regions, and no consensus has been reached for stratified pathological T stages for data to date. Data from 4607 pN0 patients with gastric cancer were analyzed. Kaplan-Meier analysis showed the similar overall survival (OS) outcomes among the 3 groups (ELNs ≤ 15, 16 ≤ ELNs ≤ 29 and ELNs ≥ 30, P = .171). However, the ELNs ≥ 30 group had a better disease-free survival (DFS) outcome compared with the others (all P < .05). An increased ELN group (ELNs ≥ 30) showed an improved OS only for pT3 patients (hazard ratio [HR] = 0.397, 95% confidence interval (CI): 0.182-0.866, P = .020), while an improved DFS for pT3 patients (HR = 0.362, 95%CI: 0.152-0.860, P = .021) and pT4 patients (HR = 0.484, 95%CI: 0.277-0.844, P = .011) in the multivariate analysis. A well discriminated and calibrated nomogram was constructed to predict the probability of the OS and DFS, with the C-index for OS and DFS prediction of 0.782 (95%CI: 0.735 to 0.829) and 0.738 (95%CI: 0.685 to 0.791), respectively. This study provides new and useful insights into the impact of ELN count on reducing stage migration and postoperative recurrence of pN0 patients with gastric cancer in 2000-2017. In conclusion, a larger number of ELNs is suggested for surgeons to prolong the prognosis of pN0 gastric cancer, especially for pT3 patients. 相似文献
24.
Makoto Usami Katsuyoshi Mitsunaga Tomohiko Irie Atsuko Miyajima Osamu Doi 《Congenital anomalies》2014,54(3):184-188
Here, we describe a simple in vitro neural crest cell (NCC) migration assay and the effects of all‐trans‐retinoic acid (RA) on NCCs. Neural tubes excised from the rhombencephalic or trunk region of day 10.5 rat embryos were cultured for 48 h to allow emigration and migration of NCCs. Migration of NCCs was measured as the change in the radius (radius ratio) calculated from the circular spread of NCCs between 24 and 48 h of culture. RA was added to the culture medium after 24 h at embryotoxic concentrations determined by rat whole embryo culture. RA (10 μM) reduced the migration of cephalic NCCs, whereas it enhanced the migration of trunk NCCs, indicating that RA has opposite effects on these two types of NCCs. 相似文献
25.
Amphoterin as an extracellular regulator of cell motility: from discovery to disease 总被引:8,自引:0,他引:8
Amphoterin is a ubiquitous and highly conserved protein previously considered solely as a chromatin-associated, nuclear molecule. Amphoterin is released into the extracellular space by various cell types, and plays an important role in the regulation of cell migration, differentiation, tumorigenesis and inflammation. This paper reviews recent research on the mechanistic background underlying the biology of secreted amphoterin, with an emphasis on the role of amphoterin as an autocrine/paracrine regulator of cell migration. 相似文献
26.
目的:研究加味生脉饮含药血清对非小细胞肺癌H460细胞增殖、细胞周期及其迁移的影响,并探讨其分子机制。方法:以生药量18 g·kg-1 ig家兔,制备加味生脉饮含药血清,同容积生理盐水ig制备空白血清,并视血清浓度为100%。体外培养H460细胞,收集对数期生长的细胞,设置10%空白血清组,2.5%,5%,10%含药血清组,1 mg·L-1 DDP组,共5组,调整细胞密度至3 000个/mL,血清作用24,48 h后,采用四甲基偶氮唑蓝(MTT)法测定细胞增殖抑制率;调整细胞密度至5×105个/mL,加入上述浓度血清作用24 h后,分别采用流式细胞仪检测细胞周期,划痕实验观察细胞迁移的情况,Western blot法检测E钙连蛋白(E-cad)及波形蛋白(Vimentin)蛋白表达的变化。结果:与空白血清组相比,加味生脉饮含药血清作用H460细胞24 h后,细胞增殖抑制率上升(P<0.01),S期细胞百分率增高(P<0.01),划痕距离较长,E-cad蛋白含量升高(P<0.01),Vimentin蛋白含量降低(P<0.01)。结论:加味生脉饮对H460细胞增殖有一定抑制作用,主要途径为S期阻滞。加味生脉饮可以抑制H460细胞的转移,其机制可能与干预H460细胞上皮间质转化有关。 相似文献
27.
28.
Schaerli P Ebert L Willimann K Blaser A Roos RS Loetscher P Moser B 《The Journal of experimental medicine》2004,199(9):1265-1275
Effective immune surveillance is essential for maintaining protection and homeostasis of peripheral tissues. However, mechanisms controlling memory T cell migration to peripheral tissues such as the skin are poorly understood. Here, we show that the majority of human T cells in healthy skin express the chemokine receptor CCR8 and respond to its selective ligand I-309/CCL1. These CCR8(+) T cells are absent in small intestine and colon tissue, and are extremely rare in peripheral blood, suggesting healthy skin as their physiological target site. Cutaneous CCR8(+) T cells are preactivated and secrete proinflammatory cytokines such as tumor necrosis factor-alpha and interferon-gamma, but lack markers of cytolytic T cells. Secretion of interleukin (IL)-4, IL-10, and transforming growth factor-beta was low to undetectable, arguing against a strict association of CCR8 expression with either T helper cell 2 or regulatory T cell subsets. Potential precursors of skin surveillance T cells in peripheral blood may correspond to the minor subset of CCR8(+)CD25(-) T cells. Importantly, CCL1 is constitutively expressed at strategic cutaneous locations, including dermal microvessels and epidermal antigen-presenting cells. For the first time, these findings define a chemokine system for homeostatic T cell traffic in normal human skin. 相似文献
29.
Jianbin Yang Dongyi Wei Weixin Wang Baohong Shen Suling Xu Yuan Cao 《International journal of clinical and experimental pathology》2015,8(9):11837-11846
Oral squamous cell carcinoma (OSCC) ranks as the fifth most common cancer worldwide with poor prognosis. Recently, tumor necrosis factor receptor-associated factor 4 (TRAF4) has attracted increasing attenuation due to its overexpression in certain cancers. However, its function and underlying mechanism in OSCC remains elusive. In this study, the high expression of TRAF4 mRNA and protein levels was noted in OSCC cell lines. Its overexpression with pcDNA3.1-TRAF4 vector transfection dramatically promoted cell proliferation and inhibited cell apoptosis, indicating a pivotal role of TRAF4 in OSCC cell growth. Simultaneously, TRAF4 elevation also increased cell invasion and migration. Mechanism analysis confirmed that TRAF4 up-regulation induced the expression of β-catenin and the downstream target molecules of cyclinD1, c-myc, Bcl-2, MMP-9 and MMP-2, indicating that TRAF4 could induce the activation of Wnt/β-catenin pathway. After pretreatment with β-catenin siRNA, the pathway was remarkably silenced. Simultaneously, cell growth, invasion and migration induced by TRAF4 were strikingly abrogated, suggesting that TRAF4 may promote OSCC cell growth, invasion and migration by Wnt/β-catenin pathway. Together, this study confirmed that TRAF4 acts as an oncogene for the development and progression of OSCC. Therefore, our study may support a promising therapeutic target for the treatment of OSCC. 相似文献
30.
目的:研究FOSL2蛋白在TGF-β1信号传导通路中的作用及FOSL2在肺腺癌中的作用机制。方法利用质粒转染、免疫沉淀、蛋白印迹等方法验证FOSL2蛋白在TGF-β1信号传导通路中的作用及机制。结果 TGF-β1诱导细胞中FOSL2蛋白的表达水平显著增加,在72 h时表达水平最高,约为对照基线水平的4倍。 FOSL2的表达与p-Smad3的着色呈正相关( r=0.85,P<0.001)。 FOSL2高表达的患者比低表达的患者生存期更短( P=0.005)。结论 FOSL2蛋白通过与Smad3蛋白的相互作用促进TGF-β1诱导的迁移,是肺腺癌治疗中的一个潜在靶点。 相似文献