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991.

Background:

No data on the incidence of pleural effusion (PE) in Chinese patients with pulmonary embolism are available to date. The aim of the current study was to investigate the frequency of PE in a Chinese population of patients with pulmonary embolism.

Methods:

This was a retrospective observational single-center study. All data of computed tomography pulmonary angiography (CTPA) performed over 6-year period on adult patients with clinically suspected pulmonary embolism were analyzed.

Results:

From January 2008 until December 2013, PE was identified in 423 of 3141 patients (13.5%) with clinically suspected pulmonary embolism who underwent CTPA. The incidence of PE in patients with pulmonary embolism (19.9%) was significantly higher than in those without embolism (9.4%) (P < 0.001). Majority of PEs in pulmonary embolism patients were small to moderate and were unilateral. The locations of emboli and the numbers of arteries involved, CT pulmonary obstruction index, and parenchymal abnormalities at CT were not associated with the development of PE.

Conclusions:

PEs are present in about one fifth of a Chinese population of patients with pulmonary embolism, which are usually small, unilateral, and unsuitable for diagnostic thoracentesis.  相似文献   
992.
Background:To investigate the surveillance trend of birth defects,incidence,distribution,occurrence regularity,and their relevant factors in Xi'an City in the last 10 years for proposing control measur...  相似文献   
993.
The most serious problem in current gene therapy is discrepancies between experimental data and actual clinical outcomes, which may be due to insufficient analyses and/or inappropriate animal models. We have explored suicide gene therapy by using various clinically relevant animal models and doubt the clinical use of maximal suicide gene expression, which has been generally recommended. To explore this subject further, we studied what expression level of suicide gene and what promoter led to the maximal clinical benefit in the case of hepatic metastatic cancer in mice. Therapeutic and adverse side effects of 4 adenoviral vectors that express herpes simplex virus thymidine kinase (HSV-tk) under different promoters were scrupulously investigated in 2 mouse models of hepatic metastasis of gastric cancer that possess clinical characteristics. Surprisingly, increases in HSV-tk expression beyond a certain point, achieved by the Rous sarcoma virus long terminal repeat promoter, not only enhanced the adverse side effects of lethal hepatotoxicity and ganciclovir-independent cytotoxicity but also failed to further increase therapeutic potential. Moreover, the carcinoembryonic antigen (CEA) tumor-specific promoter, the therapeutic potential of which had been underestimated, was much more useful-even in the case of low CEA-producing cancer-than had been previously reported. In conclusion, the optimal therapeutic expression level of a suicide gene is a novel concept and a crucial factor for successful cancer gene therapy. The present results, which contradict those of previous studies, alert researchers about possible problems with ongoing and future clinical trials that lack this concept.  相似文献   
994.
Purpose: Our purpose was to investigate whether the 3-(2-hydroxy-1-methyl-2-nitroso-hydrazino)-N-methyl-1-propanamine (NOC7), an ideal NO donor was dose dependently and cGMP-independent in restored cardiac function after global ischemia in an isolated rat heart model. Methods: Langendorff preparations of an isolated rat heart model were established. Isolated rat hearts (n = 40) were randomly divided into 5 groups (ischemic control group, NOC7 groups and NOC7+NS2028 groups). All groups were subjected to 35 min global ischemia, followed by 30 min reperfusion with Krebs-Henseleit bicarbonate buffer (KHB), and NOC7, NOC7+NS2028 at 2 and 200 μM, respectively. Left ventricular developed pressure (LVDP), the maximum and the minimal rate of rise in LVP (±dP/dt), and coronary flows were measured continuously. Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) levels were measured in myocardium homogenate, using enzyme immunoassay (EIA). Results: 30 min of global ischemia increased LVDP to 121.9±11.5% at 35 min of reperfusion of 2 μM NOC7 group and 2 μM NOC7 associated with NS2028 group from the ischemic control group (P < 0.05). While in 200 μM NOC7 group and 200 μM NOC7 associated with NS2028 group, the LVDP value only slightly reduced, resulting in a value of only 45.3±10.4% and 35.3±6.0% of baseline (P > 0.05). Conclusion: NOC7 has biphasic effect on isolated rat heart after ischemia and reperfusion myocardial contractility. This biphasic effect shows neither concentration-dependent nor the cGMP-dependent characteristics.  相似文献   
995.
Epidemiological and histopathological studies have indicated that proliferative inflammatory atrophy (PIA) of the prostate is closely associated with the onset and development of prostate cancer (PCa). However, accurate isolation of PIA still remains a difficult matter, as well as high-quality RNA extraction from isolated PIA. These issues generated a lack of molecular evidence to support the mechanistic explanation proposed for the progression of PIA to PCa. Therefore, the isolation of PIA and the extraction of high-quality RNA from isolated PIA are of great importance to further demonstrate the correlation between PIA and the development of PCa at a molecular level. In this study, clinical samples from radical prostatectomy were stored in liquid nitrogen, PIA was identified by H&E staining of cryosections, PIA clusters were isolated by manual microdissection, total RNA was extracted from the PIA clusters by Trizol, and RNA quality was determined using the Agilent 2100 Bioanalyzer. Our results showed that PIA might be isolated by manual microdissection of cryosections stored in liquid nitrogen from clinical radical prostatectomy and used for extracting high-quality RNA (RIN > 7.5) by Trizol. Therefore, the present study established a valid method to discover molecular evidence in support of the correlation between PIA and the development of PCa.  相似文献   
996.
997.
Objective: The aim of this study was to characterize the mesenchymal stromal cells (MSCs) and endothelial progenitor cells (EPCs) mobilization, and bone turnover in osteoporotic fracture healing in ovariectomized mice. Methods: In total, 112 female C57/BL mice were divided into two groups. The first group was sham-operated (SO), and the other group was ovariectomized (OVX). After three weeks, the right femora of the mice were fractured under anesthesia and internally fixed with steel pin. Peripheral blood and bone marrow were was collected for flow cytometry analysis, at 0 hours (h), 12 h, 24 h, 72 h and 168 h after fracture. MSCs and EPCs levels were assessed using cell surface antigens in different combinations (CD44+ CD34-CD45-, and CD34+ KDR+CD45-) by flow cytometry. At 0, 14, 28 and 42 days after fracture, sera were assayed for circulating levels of procollagen type I-N-terminal propeptide (P1NP) and C-terminal telopeptide of type I-collagen (CTX) by ELISA. Femurs were harvested at 2 weeks and 6 weeks after fracture for X-ray radiography, micro-computed tomography (micro-CT) and histology. Results: Our results showed that bone marrow and peripheral blood MSCs numbers of the OVX mice were significantly lower than the SO mice, at 12 h, 24 h and 72 h after fracture. In addition, circulating P1NP and CTX levels of the OVX mice were significantly higher than the SO mice, at 2 and 4 weeks. Conclusion: Results of the present study revealed disorders of bone marrow MSCs mobilization and bone turnover may partially account for the delay of osteoporotic fracture healing.  相似文献   
998.
Dendritic fibromyxolipoma is an uncommon benign soft tissue tumor. Here, we report a case in a 53-year-old man presenting a painless mass located deep in the latissimus dorsi of the right back. Microscopically, the tumor was mainly consisted of small spindle and stellate cells, abundant myxoid stroma, collagen bundles and mature adipose tissue. Immunohistochemical study showed the spindle and stellate cells were positive for CD34, Bcl-2 and Vimentim, but not for Keratin, EMA, SMA and Desmin. To date, one year after operation, the patient is well without evidence of recurrence or metastasis. The implication of this report is to provide insights into further understanding of this rare tumor with review of the literature.  相似文献   
999.
Long noncoding RNAs (lncRNAs), a class of ribonucleic molecules, participate in various cellular processes. They are highly expressed in several types of cancer and their expression was related to pathophysiological characteristics of tumor growth, therefore, they can be considered as a promising diagnostic tool and a convenient prognostic biomarker. SPRY4-IT1, belonging to a group of intron-retained lncRNAs, was reported to affect tumor development of many types of cancer. However, the expression and the role of SPRY4-IT1 in glioma are still unclear. Therefore, in this study, we examined for the first time the expression and role of SPRY4-IT1 in glioma cells. The results of our study showed that SPRY4-IT1 was up-regulated in human glioma tissues and cell lines. Knockdown of SPRY4-IT1 could inhibit glioma cell growth and migration. Moreover, knockdown of SPRY4-IT1 could inhibit epithelial-mesenchymal transition (EMT) phenotype in glioma cells. Based on these findings, SPRY4-IT1 may be used as a new target for diagnosis and treatment of glioma.  相似文献   
1000.
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