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991.
We studied the far-field optical reflection contrast spectroscopy (FORCS) properties of the following system: individual Au nanospheres (radius R) immobilized above Si substrate with different thicknesses (d) SiO2 between them. We found that peaks in the FORCS red-shift exponentially with d decreasing. The near-field coupling between the Au nanosphere and its supporting substrate is revealed to contribute to this, while the coupling strength is demonstrated to decrease exponentially with a decay length of 0.30 in units of d/R. It qualitatively agrees well in magnitude with the near-field coupling between two noble metal nanoparticles consisting of a dimer. Our results demonstrate that the FORCS can provide insight into the near-field coupling, which is significant for their applications in nano-photonics, sensing, surface-enhanced spectrascopies, etc.  相似文献   
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High expression of special AT-rich-binding protein 1 (SATB1) correlates with the advanced TNM stage and short overall and recurrence-free survival of gastric cancer (GC). A bioinformatic analysis revealed that SATB1 3′-untranslated region (3′-UTR) and long noncoding RNA UCA1 (lncRNA-UCA1) might competitively bind to microRNA-495-3p (miR-495-3p). Interestingly, lncRNA-UCA1 is also an important contributor to GC. The current study aimed to demonstrate the potential interaction among SATB1/miR-495-3p/lncRNA-UCA1 network and their effects on GC proliferation and invasion. The expression in GC and paracancerous normal tissues were assessed using real-time polymerase chain reaction and Western blot analysis. Luciferase reporter, RNA pull-down, and transfection assays were performed to determine the interaction among SATB1/miR-495-3p/lncRNA-UCA1 network in GC cells. GC proliferation and invasion were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, transwell invasion, and colony formation assays. Results showed higher expression of SATB1 and lncRNA-UCA1 but lower miR-495-3p expression in GC than in the normal tissues. In luciferase reporter assay, miR-495-3p bound to three seed sequences in SATB1 3′-UTR but only one in lncRNA-UCA1. SATB1 knockdown increased the combination of miR-495-3p with lncRNA-UCA1 but decreased lncRNA-UCA1 expression. Decreased lncRNA-UCA1 was also observed with the mimics increased miR-495-3p. These data suggested that SATB1 3′-UTR functions as a competing endogenous RNA of miR-495-3p and positively regulates lncRNA-UCA1. LncRNA-UCA1 knockdown only decreased SATB1 expression in MKN-45 cells but not in BGC-823 cells, which suggested that the regulatory effect of lncRNA-UCA1 on SATB1 by sponging miR-495-3p is cell-dependent. This study further identified that SATB1/miR-495-3p/lncRNA-UCA1 network is implicated in GC proliferation and invasion. The current study firstly revealed that SATB1 interacts with miR-495-3p/lncRNA-UCA1 network, whereby enhancing GC proliferation and invasion.  相似文献   
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Monoclonal antibodies were used to study the structure and the biosynthesis of the rabbit progesterone receptor. Proteins in nonfractionated uterine cytosol were submitted to gel electrophoresis in denaturing conditions, transferred onto nitrocellulose, and reacted with monoclonal antireceptor antibodies and 125I-protein A. A single 110,000-dalton protein was observed when precautions were taken during homogenization of the uteri and protease inhibitors used. Smaller forms of receptor (essentially of 79,000 daltons but also of 72,000 and in some experiments of 64,000 daltons) were present when these precautions were not observed and thus probably arose from artifactual proteolysis of receptor. When poly(A)+ RNA from rabbit uterus was translated in a reticulocyte lysate and the radioactive proteins precipitated by the antireceptor monoclonal antibodies, a radioactive protein of 110,000 daltons was also observed. Further evidence that this protein was the product of the translation of progesterone receptor mRNA was obtained by precipitation and immunoaffinity purification with several antireceptor monoclonal and polyclonal antibodies, inhibition of immunoprecipitation by purified receptor and its absence in a receptor-poor tissue (liver). Estrogen treatment is known to increase the concentration of progesterone receptor. RNA translation experiments showed that this effect is due to an increase in the concentration of receptor mRNA. The size of this messenger RNA was studied by sucrose gradient ultracentrifugation, followed by mRNA translation, and specific immunoprecipitation: progesterone receptor mRNA was found by this method to sediment at 20 S.  相似文献   
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In this study, we evaluated if male circumcision was associated with lower HIV acquisition for HIV (−) males and HIV (−) females during normal sexual behavior. We performed a systematic literature search of PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) databases to identify studies that compared HIV acquisition for the circumcised and uncircumcised groups. The reference lists of the included and excluded studies were also screened. Fifteen studies (4 RCTs and 11 prospective cohort studies) were included, and the related data were extracted and analyzed in a meta-analysis. Our study revealed strong evidence that male circumcision was associated with reduced HIV acquisition for HIV(−) males during sexual intercourse with females [pooled adjusted risk ratio (RR): 0.30, 95% CI 0.24 0.38, P < 0.00001] and provided a 70% protective effect. In contrast, no difference was detected in HIV acquisition for HIV (−) females between the circumcised and uncircumcised groups (pooled adjusted RR after sensitivity analysis: 0.68, 95%CI 0.40–1.15, P = 0.15). In conclusion, male circumcision could significantly protect males but not females from HIV acquisition at the population level. Male circumcision may serve as an additional approach toward HIV control, in conjunction with other strategies such as HIV counseling and testing, condom promotion, and so on.  相似文献   
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Objective

To investigate the prevalence of clinical anxiety and clinical depression in Chinese young and mid-aged patients with osteonecrosis of the femoral head (ONFH) and to analyze their potential risk factors.

Methods

Two hundred and sixteen Chinese patients with ONFH were consecutively enrolled in this cross-sectional study from January 2010 to December 2010. The Zung self-rating anxiety scale (SAS) and the Zung self-rating depression scale (SDS) were used to assess the prevalence of clinical anxiety and clinical depression. An additional questionnaire containing seventeen items of potential risk factors was completed by all patients. Binary logistic regression analysis was employed to reveal potential risk factors of anxiety and depression.

Results

The prevalence of clinical anxiety and clinical depression was 20.4% and 21.8% in Chinese young and middle-aged patients with ONFH, respectively. Binary regression analysis showed that independent risk factors correlated with high incidence of clinical anxiety included involved femoral head (OR = 3.168, 95% CI: 1.496 - 6.708) and stages of ONFH (ORIV-V / II = 5.383, 95% CI: 1.664-17.416). Independent risk factors correlated with high incidence of depression included gender (OR = 2.853, 95% CI: 1.467-5.778), comorbid diseases (OR = 4.243, 95% CI: 1.940-9.278) and stages of the disease (OR IV-V/II = 16.963, 95% CI: 4.404-65.331).

Conclusions

Patients with bilateral ONFH are inclined to have clinical anxiety, while female patients and patients with comorbid diseases might tend to get clinical depression. Advanced stages of ONFH are independent risk factors for both clinical anxiety and clinical depression.  相似文献   
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