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341.
The apoptotic ligand TNF-related apoptosis-inducing ligand (TRAIL) is believed to be a promising candidate for cancer gene therapy, yet gene therapy strategies to tackle this disease systemically are often impaired by inefficient delivery of the vector to the tumor tissue. Mesenchymal stem cells (MSCs) have been shown to home to tumor sites and could potentially act as a shield and vehicle for an anti tumor gene therapy vector. Here, we used an adenoviral vector expressing TRAIL to transduce MSCs and studied the apoptosis-inducing activity of these TRAIL-carrying MSCs on esophageal cancer cell Eca-109. Our results showed that, in vitro, TRAIL-expressing MSCs were able to inhibit proliferation and induce apoptosis in Eca-109 cells by an MTT assay, co-culture experiments and flow cytometry analysis. In vivo, TRAIL-expressing MSCs also displayed an ability to inhibit tumor growth in an Eca-109 xenograft mouse model. Together, our findings indicated that the gene therapy strategy of MSCs-based TRAIL gene delivery has a wide potential value for improving the treatment of esophageal cancer.  相似文献   
342.
胃食管反流病(gastroesophaeal reflux disease,GERD)是医疗实践中的最常见的疾病之一,其发病率在世界范围内呈逐年上升趋势,且随年龄增长而增加,40-60岁为高发年龄[1]。GERD是一种由胃、十二指肠内容物反流入食管引起不适症状和(或)并发症的疾病,GERD在临床上大致可分为:糜烂性食管炎(EE)(反流性食管炎(RE))和非糜烂性食管炎(NERD)。其中NERD最多见,约占60%。GERD远期危害较小,但其病情漫长且极易复发,严重影响了生活质量。主要表现为食管症状(包括典型的烧心和反流)和食管外症状(包括咽部异物感、咳嗽、声嘶、哮喘、咽喉炎等表现),还有增加发展为Barrett食管及食管癌的危险[2,3]。GERD的治疗目的是愈合食管炎,快速缓解症状、减少复发、提高生活质量,治疗方法主要包括以下4个方面:一般治疗,药物治疗,内镜下治疗和外科治疗。近年来已成为国内外研究的热点,本文就近年来对GERD的治疗进展做一综述。  相似文献   
343.
目的:探讨单体位左胸左颈两切口的手术方式在外科治疗食管上段癌中的应用效果。方法:选择2008年1月至2012年4月间我院收治的食管上段癌患者49例,根据手术方法分为研究组(n=19)和对照组(n=30),研究组行单体位左胸左颈两切口管型吻合器治疗,对照组行传统颈、胸、腹三切口方法治疗。观察两组手术时间、术中出血量、清扫淋巴结数、术后引流量和术后并发症等。结果:研究组手术时间显著短于对照组,术中出血量和术后引流量显著低于对照组(P0.05)。两组清扫淋巴结数比较无统计学差异(P0.05)。两组患者均全部治愈出院,研究组肺不张、反流性食管炎、吻合口瘘、吻合口狭窄等发生率显著低于对照组(P0.05)。结论:单体位左胸左颈两切口管型吻合器治疗食管上段癌安全,可靠,省时易行,是一种较好的手术方式,值得推广。  相似文献   
344.
It has been reported that the trimethylation of histone 3 on lysine 27 (H3K27me3) is required for enhancer of zeste homology 2 (EZH2)-mediated repression of various genes essential for tumorigenesis and tumor development. Here, we reported the expression of EZH2 and H3K27me3 in esophageal squamous cell carcinoma (ESCC) specimens was higher than the pericarcinoma esophageal specimens. Their expression was positively associated with the poor prognosis of ESCC patients. EZH2 expression, histological grade and distant lymph node metastasis were all independent factors for poor prognosis of ESCC. In addition, enforced expression of EZH2 in esophageal cancer-derived cells could increase the overall H3K27me3 level. Our results suggested the expression of EZH2 and H3K27me3 could serve as biomarkers in the prediction of ESCC patients’ survival and ESCC metastasis.  相似文献   
345.
P-type ATPases as drug targets: Tools for medicine and science   总被引:1,自引:0,他引:1  
P-type ATPases catalyze the selective active transport of ions like H+, Na+, K+, Ca2+, Zn2+, and Cu2+ across diverse biological membrane systems. Many members of the P-type ATPase protein family, such as the Na+,K+-, H+,K+-, Ca2+-, and H+-ATPases, are involved in the development of pathophysiological conditions or provide critical function to pathogens. Therefore, they seem to be promising targets for future drugs and novel antifungal agents and herbicides. Here, we review the current knowledge about P-type ATPase inhibitors and their present use as tools in science, medicine, and biotechnology. Recent structural information on a variety of P-type ATPase family members signifies that all P-type ATPases can be expected to share a similar basic structure and a similar basic machinery of ion transport. The ion transport pathway crossing the membrane lipid bilayer is constructed of two access channels leading from either side of the membrane to the ion binding sites at a central cavity. The selective opening and closure of the access channels allows vectorial access/release of ions from the binding sites. Recent structural information along with new homology modeling of diverse P-type ATPases in complex with known ligands demonstrate that the most proficient way for the development of efficient and selective drugs is to target their ion transport pathway.  相似文献   
346.
347.
Chemosensitivity to anticancer drugs was compared between two human esophageal carcinoma cell lines, T.Tn and YES-6 cells. T.Tn cells were more resistant than YES-6 cells to peplomycin (PEP) but not to the other anticancer drugs such as camptothecin, mitomycin C and cytosine arabinoside. Western blot analysis showed higher expression levels of m-calpain and activated μ-calpain in T.Tn cells than in YES-6 cells. On the other hand, YES-6 cells showed a high expression level of calpastatin, which is a calpain-specific endogenous inhibitor. To investigate whether calpain activity was involved in the chemosensitivity, T.Tn cells were transfected with calpastatin cDNA in an inducible expression vector. The induction of calpastatin was accompanied by increased chemosensitivity to PEP. The increases in calpastatin levels were followed by serial increases in the expression levels of NF-κB p65 and Fas. Since purified m- or μ-calpain degraded NF-κB p65 in vitro, it is possible that calpastatin suppressed calpain-mediated degradation of NF-κB p65. Fas ligand (Fas-L) protein levels increased after treatment of the parental T.Tn and calpastatin-transfected cells with PEP, suggesting the synergism between calpastatin-induced Fas and PEP-induced Fas-L. These results suggest that calpain/calpastatin expression levels are effective markers for predicting the sensitivity of human esophageal carcinoma cells to PEP. This work was supported by the Grant for 21st Century COE (Center of Excellence) Program and a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan.  相似文献   
348.
Sheu JN  Chen MC  Lue KH  Cheng SL  Lee IC  Chen SM  Tsay GJ 《Cytokine》2006,36(5-6):276-282
Urinary tract infection (UTI) is a common clinical disorder in younger infants and children and may result in permanent renal damage. The inflammatory cytokines interleukin (IL)-6 and IL-8 play an important role in response to bacterial infection. This prospective study investigated the association between serum and urine IL-6 and IL-8 levels and acute pyelonephritis confirmed by (99m)Tc-dimercaptosuccinic acid (DMSA) scan. A total of 78 children aged 1-121 months with a diagnosis of first-time febrile UTI were included. The following inflammatory markers were assessed: fever; white blood cells count (WBC); C-reactive protein (CRP); and serum and urine IL-6 and IL-8. The patients were divided into the acute pyelonephritis group (n=42) and the lower UTI group (n=36) according to the results of DMSA scan. Fever, WBC and CRP levels were significantly higher in children with acute pyelonephritis than in those with lower UTI (all p <0.001). Significantly, higher initial serum and urine IL-6 and IL-8 levels were found in children with acute pyelonephritis than in those with lower UTI (all p <0.001). Serum and urine IL-6 in children with acute pyelonephritis were positively correlated with fever, CRP and leucocyturia. These results indicate that both serum and urine IL-6 and IL-8 levels, particularly IL-6, are useful diagnostic tools for early recognition of acute pyelonephritis in febrile children.  相似文献   
349.
为探讨ODC和AdoMetDC双反义腺病毒载体(Ad-ODC-AdoMetDCas)对食管癌Eca109细胞凋亡作用的影响,应用MTT法观察Ad-ODC-AdoMetDCas对食管癌Eca109细胞生长增殖的影响,采用Western blot和HPLC的方法分别检测腺病毒载体对食管癌Eca109细胞中ODC和AdoMetDC蛋白表达以及胞内多胺含量的抑制作用,同时应用原位末端标记(TUNEL) 法观察Ad-ODC-AdoMetDCas对食管癌Eca109细胞凋亡作用的影响, 透射电镜进一步观察细胞超微结构的改变. 实验结果显示,应用MTT法观察发现Ad-ODC-AdoMetDCas对食管癌Eca109细胞生长增殖有显著抑制作用. 以Ad-ODC- AdoMetDCas感染食管癌Eca109细胞,可明显抑制食管癌Eca109细胞中ODC和AdoMetDC基因表达. HPLC结果显示,食管癌Eca109细胞感染Ad-ODC-AdoMetDCas后,细胞内3种多胺含量都明显降低. TUNEL标记检测结果显示Ad-ODC-AdoMetDCas可明显引起食管癌Eca109细胞凋亡.透射电镜观察到典型的细胞凋亡特征(表现细胞体积缩小,核皱缩、碎裂,染色质呈块状边集等). 实验表明,ODC和AdoMetDC双反义腺病毒载体(Ad-ODC-AdoMetDCas)具有显著抑制食管癌细胞生长增殖,降低细胞多胺合成,促进细胞凋亡,为探讨食管癌基因治疗的可行性提供实验依据.  相似文献   
350.
Abstract. Larval gut characters of 45 species of black flies, representing 17 subgenera and 15 genera, were studied for their utility in taxon diagnosis and phylogenetic inference. Phase-contrast and scanning electron microscopy revealed a wealth of new characters in the esophageal armature of the foregut. Larval gut morphology, particularly characters of the esophageal armature, varied significantly among taxa, permitting generic diagnoses. A cladogram inferred from 13 gut characters supported a sister-group relationship between Parasimulium and the remaining simuliids, but did not show a strong phylogenetic signal for the current, well-supported concept of tribal level monophyly.  相似文献   
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