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1.
 目的 探讨NRP-1单克隆抗体(NRP-1 MAb)的特异性,以及不同剂量的NRP-1 MAb治疗乳腺癌裸鼠移植瘤的疗效。方法 Western blot和共聚焦免疫荧光法检测NRP-1 MAb是否识别MCF7细胞上NRP-1蛋白。将MCF7细胞接种于BALB/c裸鼠皮下建立乳腺癌细胞移植瘤模型,并进行瘤组织传代。传代的肿瘤体积生长至300~500 mm3时,随机分为对照组、NRP-1 MAb低剂量组、中剂量组和高剂量组,每组6只,给药7次。观察荷瘤裸鼠一般状况,测量瘤体大小及裸鼠体重。实验结束时剥离瘤体称重,提取组织蛋白,Western blot检测组织中VEGF蛋白和NRP-1蛋白的表达量。结果 NRP-1MAb成功识别MCF7细胞上的NRP-1蛋白;NRP-1 MAb能够有效抑制MCF7细胞裸鼠移植瘤的生长,低剂量组(1 mg/kg)抑瘤率为47.01%,中剂量组(5 mg/kg)抑瘤率为65.70%,高剂量组(10 mg/kg)抑瘤率为69.19%。。结论 NRP-1 MAb能够识别并有效结合MCF7细胞膜上的NRP-1蛋白,且可抑制MCF7细胞移植瘤的生长,NRP-1 MAb抑制移植瘤的增长可能与下调NRP-1和VEGF表达有关。  相似文献   
2.
Renal-cell carcinoma remains one of the elusive cancers that lacks a biomarker. It is the eighth most commonly diagnosed malignancy in the United States, and the incidence has slowly trended upward. In addition to the increase in newly diagnosed cases, the prevalence and overall survival of individuals with kidney cancer also has increased substantially. This formal review synopsizes the literature regarding the current treatment landscape, the utility of biomarkers in renal-cell carcinoma, and future directions regarding next-generation sequencing of circulating tumor DNA.  相似文献   
3.
Thyroid hormones affect testicular development as well as functions like spermatogenesis and steroidogenesis, thereby influencing male fertility. Our group earlier showed that the stimulatory role of the thyroid hormone, T3, on the production of vascular endothelial growth factor (VEGF) by murine Leydig cells is mediated by steroids and hypoxia-inducible factor-1 (HIF-1α). The current study further defines the signalling pathway(s) utilised by T3 to stimulate the production of steroids, VEGF and HIF-1α in mouse Leydig tumour cell line (MLTC-1). Specific inhibitors for different signalling molecules were used to study the role of cyclic AMP (cAMP), and its downstream mediators. Expression of VEGF and HIF-1α mRNA were measured by quantitative RT-PCR; VEGF secretion by ELISA; steroid secretion by radioimmunoassay and HIF-1α protein levels by western blotting. Inhibitors of adenylate cyclase (AC), protein kinase A (PKA), sarcoma kinase (SrcK), phosphoinositide 3-kinase (PI3K) and MAP kinase kinase (MEK1/2) abolished the T3-induced increase in VEGF mRNA and protein levels. The same signalling molecules also mediated the increased production of steroids and HIF-1α protein in response to T3. Therefore, it was concluded that T3 stimulates steroid secretion and HIF-1α protein in MLTC-1 cells through the AC-cAMP-PKA-PI3K-MEK pathway, which in turn stimulate VEGF production.  相似文献   
4.
目的基于网络药理学分析丹参治疗微循环障碍的分子生物学机制。方法借助TCMSP、PubChem Search、Genecards数据库和Swiss target prediction在线工具得到丹参的活性成分治疗微循环障碍的作用靶标,利用Cytoscape 3.3.0软件构建丹参活性成分-微循环障碍作用靶标网络,通过STRING数据库构建靶蛋白相互作用(PPI)网络,通过生物学信息注释数据库(DAVID)进行基因本体(GO)生物学过程和京都基因与基因组百科全书(KEGG)通路富集分析。结果从丹参中共筛选出治疗微循环障碍的65个相关活性成分,并发现微循环障碍相关的9个关键靶点。GO和KEGG通路富集分析发现,丹参治疗微循环障碍可能与氧化还原、钙离子稳态等生物过程有关,能够调节血管内皮生长因子信号通路、神经突触信号传导、催产素信号通路、醛固酮-调节钠重吸收等信号通路。结论丹参治疗微循环障碍体现了多成分、多靶点、多途径的作用特点,为进一步开展丹参治疗微循环障碍作用机制研究提供了新的思路和方法。  相似文献   
5.
目的 为探究吉西他滨(GEM)膀胱灌注治疗在经尿道膀胱肿瘤电切术(TURBt)后的非肌层浸润性膀胱癌(NMIBC)患者的临床效果以及对血清VEGF的影响。方法 回顾性选取2015年1月~2019年6月在玉溪市人民医院接受TURBt治疗的132例NMIBC患者为研究对象,将患者分为GEM组和吡柔比星组(THP组),每组均为66例。两组均行TURBt治疗,GEM组术后立即采取GEM膀胱灌注,THP组术后立即采取THP膀胱灌注。通过对比两组术后灌注治疗过程中的不良反应,并随访1年,监测两组术后0.5年、1年的复发情形;分别在灌注前、灌注后0.5年及1年抽取4 mL空腹静脉血,检测血清VEGF的水平。结果 GEM组灌注后0.5年、1年复发率低于THP组,复发时间长于THP组,具有统计学意义(P<0.05);两组灌注后0.5年、1年血清VEGF水平均低于灌注前,两组灌注后1年血清VEGF水平与灌注后0.5年水平相比,处于一个降低的趋势,但GEM组患者灌注后0.5年、1年血清VEGF均明显低于THP组,下降的趋势更大,差异有统计学意义(P<0.05)。结论 GEM膀胱灌注治疗在NMIBC病人行TURBt后取得的临床效果较好。  相似文献   
6.
目的探讨定坤丹联合炔诺酮治疗月经不调的临床疗效。方法选取2017年3月—2019年3月在开封市人民医院治疗的月经不调患者92例,根据用药的差别分为对照组(46例)和治疗组(46例)。对照组口服炔诺酮片,2.5mg/次,4次/d;治疗组在对照组基础上口服定坤丹,7 g/次,2次/d。两组患者均经过3个月经周期治疗。观察两组患者临床疗效,同时比较治疗前后两组患者临床症候积分、性激素水平、月经失血图(PBAC)、中华生存质量量表(Ch QOL)、高温相评分(HPS)、匹茨堡睡眠质量指数量表(PSQI)评分以及血清细胞因子水平。结果治疗后,对照组临床有效率为82.61%,显著低于治疗组的97.83%,两组比较差异具有统计学意义(P0.05)。治疗后,两组患者症候积分明显下降(P0.05),且治疗组临床症候积分明显低于对照组(P0.05)。治疗后,两组血清孕酮(P)、雌二醇(E2)水平显著升高(P0.05),黄体生成激素(LH)、促卵泡成熟激素(FSH)水平显著下降(P0.05),且治疗组E2、P、LH和FSH水平明显好于对照组(P0.05)。治疗后,两组PBAC和PSQI评分显著下降(P0.05),Ch QOL和HPS评分显著升高(P0.05),且治疗组PBAC、PSQI、Ch QOL和HPS评分明显好于对照组(P0.05)。治疗后,两组患者血清表皮生长因子(EGF)、血管内皮生长因子(VEGF)水平均明显升高(P0.05),且治疗组EGF和VEGF水平明显高于对照组(P0.05)。结论定坤丹联合炔诺酮片治疗月经不调可有效改善患者临床症状,改善机体性激素水平,提高患者睡眠和生活质量。  相似文献   
7.
8.
Using JEG-3 and BeWo cells, we examined the effect of “real life” mixtures of polycyclic aromatic hydrocarbons (PAHs), at doses reported in maternal blood (Mix I) and in placental tissue (Mix II), on human chorionic gonadotropin (hCG), placental lactogen (hPL) and placental growth factor (hPLGF) secretion, protein expression and immunolocalization. Additionally, the action of PAH mixtures on basal and hormone-stimulated matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) protein expression was evaluated. Under basal conditions, the PAH mixtures increased hCG and decreased hPLGF levels in both cell lines, while hPL expression was stimulated in JEG-3 and inhibited in BeWo. There was no effect on the MMP-2/MMP-9 ratio or VEGF expression. In hormone-stimulated cells, PAH mixtures changed the MMP-2/MMP-9 ratio in JEG-3 cells in favor of MMP-9, while in BeWo MMP-2 was favored. The effect on VEGF expression was cell specific and dependent on the mixture. In hCG-treated cells, only Mix II inhibited VEGF expression in JEG-3 cells. Neither PAH mixtures affected this protein in BeWo cells. In hPL-treated cells, Mix I had a stimulatory effect in JEG-3 cells, while Mix II exerted an inhibitory effect in BeWo cells. In hPLGF-treated cells, Mix II decreased in JEG-3 cells, but in BeWo cells, both mixtures increased VEGF expression. Considering that the evaluated protein hormones play crucial roles in angiogenesis and neovascularization in the placenta, “real life” PAH mixtures by disrupting protein hormones levels, the MMP-2/MMP-9 ratio and VEGF expression can lead to insufficiency and many pregnancy-related disorders.  相似文献   
9.
BackgroundInflammation is a known risk factor of cancer development, including inflammation-driven leukemogenesis. Evaluation of inflammation-related cytokines in early diagnosis stages is crucial to understand the development of hematologic malignancy. Our aim was to measure three cytokines- neutrophil gelatinase-associated lipocalin (NGAL), vascular endothelial growth factor (VEGF), and soluble receptor for advanced glycation end-products (sRAGE) in bone marrow (BM) samples from patients diagnosed with hematologic malignancy and compare these measurements with the control. Additionally, we evaluated whether NGAL was significantly associated with sRAGE, VEGF, and several hematological parameters.MethodsBM samples were collected from 73 patients, who were classified into myeloproliferative neoplasm (MPN), acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), plasma cell neoplasm (PCN) and control groups according to the BM smear and pathology review. An immunoassay, a Luminex assay, and an enzyme-linked immunosorbent assay were used to quantitate NGAL, VEGF, and sRAGE, respectively, while all measurements of NGAL, VEGF and sRAGE were performed on BM supernatants. Data on hematological parameters were collected from medical records. Intergroup comparisons were performed using the Kruskal-Wallis H-test and Pearson Chi-Square test. Single and multiple regression analyses were performed to analyze the relationships among the parameters.ResultsThe independent factors associated with NGAL were neutrophil counts and VEGF. As for both NGAL and VEGF, the MPN (n = 23) group showed the highest level, while the MDS (n = 12) group showed low levels. NGAL levels in the AML (n = 13) and MDS groups were lower than in the control group (n = 14). The MPN group demonstrated higher VEGF levels than the AML and MDS groups. The MDS group showed lower VEGF levels than the PCN (n = 11) group. No statistical difference between the hematologic malignancy and control groups or among the hematologic malignancy groups was observed for sRAGE levels.ConclusionNGAL was related to neutrophil count and VEGF. NGAL and VEGF showed similar intergroup patterns, reflecting that NGAL was associated with VEGF.  相似文献   
10.
Purpose: To investigate the presence of the Vascular Endothelial Growth Factor (VEGF) and its receptor (VEGFR) in human orbital preadipocytes, and to evaluate the effect of VEGF on human orbital preadipocyte differentiation and adipogenesis in vitro.Results: Four isoforms of VEGF (VEGF121, 155, 189, and 206), VEGFR-1, VEGF-2, and neuropilin-1 were expressed in human orbital preadipocytes. Treatment with 100 ng/ml VEGF induced higher expressions of C/EBPα and LPL than the non-treated control (p = 0.03 and p = 0.01) or treatment with 50ng/ml (p = 0.04 for both). At both concentrations VEGF enhanced the accumulation of intra-cytoplasmic lipid versus the control, and treatment with 100 ng/ml VEGF induced more lipid accumulation than treatment with 50 ng/ml VEGF (p = 0.03).Conclusions: VEGF and VEGFR were observed in human orbital preadipocytes, and exogenous VEGF enhanced adipogenesis in these cells. These results suggest that VEGF plays a role as an autocrine or paracrine growth factor during human orbital preadipocyte differentiation.  相似文献   
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