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排序方式: 共有144条查询结果,搜索用时 31 毫秒
1.
Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicatedin advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-EastIndia and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examinationfrom September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational(epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved,standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters.Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantlyhigher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patientswith well differentiated histology and was more common in patients with stage II and III diseases, but neither of theassociations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours(56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patientswith locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlatedsignificantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expressionis recommended to provide a therapeutic advantage in Indian patients.  相似文献   
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BackgroundThe overexpression of CXCR4, C-Met and VEGF-C present widely in breast tumors, they may be markers of resistance to treatment. However, the studies are still controversial. Thus, this meta-analysis aims to research the relationship between the overexpression of CXCR4, C-Met, VEGF-C and clinical prognosis among breast cancer patients.MethodsPubMed and EMBASE databases were searched for eligible literature. The outcomes of interest were progression-free survival (PFS), relapse-free survival (RFS) and overall survival (OS). All tests of statistical significance were two sided.ResultsA total of 7830 patients from 28 eligible studies were assessed. The overexpression of the CXCR4 and C-Met both implied significantly worse PFS compared with normal expression [HR = 2.56, 95% CI = 1.34–4.91, P = 0.005; and HR = 1.63 95% CI = 1.20–2.22, P = 0.002]. Meanwhile, if patients had high expression of CXCR4, they would have worse OS [HR = 2.56 95% CI = 1.52–4.31, P = 0.000]. However, the overexpression of C-Met did not relate to OS for breast cancer patients [HR = 1.16, 95% CI = 0.69–1.95, P = 0.570]. Meanwhile, no statistically significant different was observed with respect to PFS and OS between VEGF-C overexpression and normal expression [HR = 0.99, 95% CI = 0.64–1.52, P = 0.968; and HR = 0.76, 95% CI = 0.43–1.33, P = 0.333].ConclusionsOur meta-analysis showed that CXCR4 and C-Met were efficient prognostic factors for breast cancer. Nevertheless, highly expressing VEGF-C was not related to progression-free survival and overall survival. Due to the small samples and insufficient date, further studies should be conducted to clarify the association between the overexpression of CXCR4 or C-Met or VEGF-C and the prognosis about breast cancer patients.  相似文献   
3.
Objective: To examine expression profile of magnesium responsive genes (MRGs) in placentas of normoevolutive and preeclamptic women. Methods: The expression profiles of MRGs were determined in placentas of normoevolutive (N?=?26) and preeclamptic (N?=?25) women by RT-qPCR. Results: Among all tested MRGs (9) only SLC41A1 (encoding for Na+/Mg2+ exchanger) was significantly overexpressed in ~54.2% of preeclamptic (n?=?24) and in ~9.5% of normoevolutive (n?=?21) specimens. On average, SLC41A1 was overexpressed sixfold in the preeclamptic group. Presence of SLC41A1 in placentas was confirmed by Western blot analysis. Conclusion. SLC41A1 is significantly overexpressed in nearly 55% of preeclamptic placentas. This may indicate a direct contribution of changed Mg homeostasis in the development of preeclampsia.  相似文献   
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目的 NeoE是费氏链霉菌合成新霉素途径中一种重要的NAD(P)+依赖性脱氢酶,本研究的目的是预测其生物学性质及其对新霉素合成能力的影响。方法 由NCBI网站蛋白质数据库获得NeoE氨基酸序列,利用生物信息学网站及软件分析预测其特征。随后构建neoE过表达质粒,以接合转移方式得到高产重组菌株SF-neoE。最后经摇瓶发酵以及相关基因的转录分析探究NeoE对新霉素生物合成的影响。结果 NeoE由340个氨基酸组成,理论相对分子质量约为35228.33 Da,理论pI值5.14,不存在信号肽和跨膜区,是一个疏水性的稳定胞内蛋白。对含空载质粒菌株和重组菌株摇瓶发酵与RT-qPCR分析,结果表明第48小时neoE的相对表达水平较对照菌株提高了2.1倍,且NeoE的过量表达使得新霉素效价提高42%。结论 该结果为提高新霉素效价提供思路,并为后续定向改造NeoE探究其对费氏链霉菌生长代谢的影响奠定理论基础。  相似文献   
6.
目的 探讨富含亮氨酸重复序列免疫球蛋白样蛋白3(LRIG3)基因过表达对人神经母细胞瘤细胞系SK-N-MC细胞生物学行为的影响。方法 体外培养人神经母细胞瘤细胞系SK-N-MC细胞,分成空白对照组(A组,不转染任何载体或质粒)、载体组(B组,转染载体)和LRIG3过表达组(C组,转染含LRIG3基因过表达质粒)。 荧光定量PCR和免疫印迹法检测LRIG3、Caspase-3和Caspase-9的mRNA和蛋白表达水平。Transwell试剂盒检测细胞侵袭能力,AV-PI试剂盒检测细胞凋亡水平,CCK-8试剂盒检测细胞增殖能力。结果 C组Caspase-3和Caspase-9的mRNA和蛋白表达水平以及细胞凋亡率明显高于A组和B组(P<0.05),细胞增殖率和细胞侵袭能力明显低于A组和B组(P<0.05),而A组和B组之间均无统计学差异(P>0.05)。结论 LRIG3过表达可以抑制人神经母细胞瘤细胞系SK-N-MC细胞增殖和侵袭,促进其凋亡,其机制可能与促进Caspase-3和Caspase-9表达有关  相似文献   
7.
Background: Oral submucous fibrosis (OSF) is a chronic debilitating condition characterized by juxta-epithelial fibrosis. The main etiological agent associated with the high-risk precancerous condition is areca nut use. S100A7 is a member of the largest calcium-binding proteins exclusively found in vertebrates and are associated with the regulation of numerous intracellular and extracellular functions. The aim of this study was to investigate the expression of protein S100A7 in salivary samples of individuals with stage I OSF and healthy controls. Methods: This study included 63 participants, 30 of whom had OSF stage I and 33 healthy controls. Nonprobability quota sampling technique was utilized for recruitment of the study participants. A structured baseline questionnaire was used to collect demographic data. Saliva samples were collected by passive droll technique in a sterile container. Salivary levels of S100A7 were quantified by enzyme-linked immunosorbent assay. For the normality of the data Shapiro Wilk test was performed. Student t-test was commuted to evaluate the expression of S100A7 protein expression between both the study groups. Results: The mean salivary S100A7 value for stage I OSF group was 0.334 ng/ml, compared to 0.172 ng/ml for healthy controls. Student t-test reported a statistically significant difference, indicating higher levels of S100A7 in stage I OSF group than in healthy controls (p < 0.001). In the individual group analysis, a significant negative correlation was found between salivary S100A7 and duration of areca nut use (r = –0.45, p = 0.009) and gutka chewing (r = –0.20, p = 0.03), while a significant positive correlation was found between salivary S100A7 and mouth opening (r = 0.03, p = 0.04). Conclusions: Higher levels of S100A7 protein level was seen in stage I OSF group in comparison to the healthy individuals. Results of our study suggest that S100A7 could be used as a surrogate assessment to identify patients at risk of OSF development.  相似文献   
8.
ObjectiveThe Gynecologic Oncology Group (GOG) performed a detailed analysis of p53 overexpression in previously-untreated women with invasive early or advanced stage epithelial ovarian cancer (EOC).MethodsWomen were eligible for the study if they provided a tumor block for translational research and participated in either GOG-157, a randomized phase III trial of three versus (vs.) six cycles of paclitaxel + carboplatin in high-risk, early stage EOC, or GOG-111, a randomized phase III trial of cyclophosphamide + cisplatin vs. paclitaxel + cisplatin in suboptimally-resected, advanced stage EOC. The N-terminal DO-7 p53 antibody was used to examine the expression of the major normal and mutant p53-isoforms. p53 overexpression was defined as ≥ 10% tumor cells exhibiting nuclear staining.Resultsp53 was overexpressed in 51% (73/143) and 66% (90/136) of cases in the GOG-157 and GOG-111 cohorts, respectively. In the GOG-157 cohort, p53 overexpression was not associated with any clinical characteristics or overall survival (OS) but was associated with worse progression-free survival (PFS) (logrank test: p = 0.013; unadjusted Cox modeling: p = 0.015). In the GOG-111 cohort, p53 overexpression was associated with GOG performance status (p = 0.018) and grade (p = 0.003), but not with age, stage, cell type or with tumor response and disease status after primary chemotherapy, PFS or OS. Adjusted Cox regression modeling demonstrated that p53 overexpression was not an independent prognostic factor for PFS or OS in either cohort.Conclusionsp53 overexpression assessed by DO-7 immunostaining is common in early and advanced stage EOC, but has limited prognostic value in women treated with surgical staging and platinum-based combination chemotherapy.  相似文献   
9.
Spleen tyrosine kinase (SYK), a non-receptor protein tyrosine kinase, is reported to be related to cell survival after A/H (anoxia/hypoglycemia) insult. However, the role of SYK in cardiocyte survival under A/H injury remains unclear. In this study, we aimed to gain insight into the role and molecular mechanism of SYK in cardiocytes exposed to A/H stress. The mRNA and protein expressions of SYK in H9c2 cardiocytes exposed to A/H injury, separately detected by real-time quantitative PCR and Western blot, were both robustly up-regulated. Then we overexpressed SYK in H9c2 with A/H injury, and found that cell viability was significantly increased and LDH leakage was decreased. Moreover, apoptosis measured by annexin V–fluorescein isothiocyanate/propidium iodide and reactive oxygen species (ROS) identified by 2′, 7′-dichlorofluorescin diacetate were markedly inhibited in H9c2 with A/H injury following SYK overexpression. Furthermore, we observed that SYK could induce HO-1 expression by regulating the Akt phosphorylation level in H9c2 with A/H injury, protecting H9c2 from the injury induced by A/H treatment.  相似文献   
10.
Brain deposition of the amyloid-beta protein (Abeta) is a frequent complication of Down's syndrome (DS) patients. Abeta peptide is generated by endoproteolytic processing of Abeta precursor protein by gamma and beta secretases. Recently a transmembrane aspartyl protease, BACE, has been identified as the beta-secretase, and its homologous BACE-2 has also been described. BACE-2 gene resides on chromosome 21 in the obligate DS region. It cleaves Abeta precursor protein at its beta site and more efficiently at a different site within Abeta. In the present study we characterized the BACE-2 gene and protein expression in the DS patients and healthy control. We analyzed, by using a nonradioactive ribonuclease protection assay, the levels of BACE-2 mRNA expression in primary skin fibroblasts. The analysis revealed a 2.6-fold increase in BACE-2 mRNA levels in the DS group compared to the levels observed in the control group. Western blot analysis revealed no difference between DS and control in BACE-2 protein levels in the intracellular compartment. In the medium conditioned by fibroblast, we revealed an evident secretion of BACE-2 protein, represented by two different molecular weights, remarkably increased in DS fibroblasts. BACE-2 overexpression was also confirmed in the DS fetal brains and human neural embryonic DS stem cells in which conditioned media BACE-2 was secreted. These data highlight the importance of the extracellular compartment where BACE-2 overexpression could play a role in plaque formation in DS patients.  相似文献   
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