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81.
Molecular Biology Reports - Coronary artery disease (CAD) is considered to be one of the most pivotal causes of death in the world. Over the past two decades, significant changes occurred in the...  相似文献   
82.

Background

The patient-physician relation begins when the physician introduces himself with name and function. Most institutions request a nametag with name and function to be worn. Although nametags are consequently worn, the optimal position for the nametag is unknown. It was the purpose of this study to identify whether positioning the nametag on the right or the left chest side provides better visibility to the patient.

Method and Material

One hundred volunteers, blinded to the experimental setup, presented for an orthopedic consultation in a standardized manner. The nametag of the physician was randomly positioned on the left chest side and presented to 50 individuals (age 35 years (range 17 to 83)) or the right chest side and then presented to 50 other individuals (35 years (range 16 to 59)). The time of the participant noticing the nametag was documented. Subsequently, the participant was questioned concerning the relevance of a nametag and verbal self-introduction of the physician.

Results

38% of the participants noticed the nametag on the right as opposed to 20% who noticed it if placed on the left upper chest (p = 0.0473). The mean time to detection was 9 (range 1–40) seconds for nametags on the right and 25.2 seconds (range 3 to 49, p = 0.006) on the left. For 87% of the participants, a nametag is expected and important and nearly all participants (96%) expected the physician to introduce himself verbally.

Conclusion

It is expected that a physician wears a nametag and introduce himself verbally at the first encounter. Positioning the nametag on the right chest side results in better and faster visibility.  相似文献   
83.
Biological Trace Element Research - Exposure to arsenic (AS) causes abnormalities in the reproductive system; however, the precise cellular pathway of AS toxicity on steroidogenesis in developing...  相似文献   
84.
Background aims. The clinical application of mesenchymal stromal cells (MSC) faces several obstacles, such as the lack of a standard method for direct isolation as well as a low frequency and concern about the safety of their in vitro expansion. Although the density-gradient separation technique is used as the first step in most methods of MSC isolation to enrich mononuclear cells, the efficiency of this method has not so far been examined. This study was designed to address this issue. Methods. Human bone marrow (BM) samples were laid over Ficoll-Paque, and after centrifugation the upper and lower fractions were cultured separately. Surface markers, differentiation potential and the number of emerged cells were determined. Results. The isolated cells from both the upper and lower fractions were characteristic of MSC. Although it is commonly believed that MSC are single suspending mononuclear cells and so are enriched in the upper fraction of Ficoll-Paque after density-gradient separation, our data showed that considerable numbers of these cells were accumulated in the lower fraction. Further data indicated that MSC were actually present as cell aggregates in BM and they could be enriched effectively by a simple filtration method. Conclusions. The aggregate nature of MSC in BM is in agreement with the concept that they are one of the main elements of the hematopoietic stem cell niche. In addition, the simple filtration method proposed here to isolate cell aggregates may provide opportunities for instant stem cell therapy without the need for extensive in vitro expansion.  相似文献   
85.
86.
Lung cancer causes more deaths in men and women than any other cancer related disease. Currently, few effective strategies exist to predict how patients will respond to treatment. We evaluated the serum metabolomic profiles of 25 lung cancer patients undergoing chemotherapy ± radiation to evaluate the feasibility of metabolites as temporal biomarkers of clinical outcomes. Serial serum specimens collected prospectively from lung cancer patients were analyzed using both nuclear magnetic resonance (1H-NMR) spectroscopy and gas chromatography mass spectrometry (GC–MS). Multivariate statistical analysis consisted of unsupervised principal component analysis or orthogonal partial least squares discriminant analysis with significance assessed using a cross-validated ANOVA. The metabolite profiles were reflective of the temporal distinction between patient samples before during and after receiving therapy (1H-NMR, p < 0.001: and GC–MS p < 0.01). Disease progression and survival were strongly correlative with the GC–MS metabolite data whereas stage and cancer type were associated with 1H-NMR data. Metabolites such as hydroxylamine, tridecan-1-ol, octadecan-1-ol, were indicative of survival (GC–MS p < 0.05) and metabolites such as tagatose, hydroxylamine, glucopyranose, and threonine that were reflective of progression (GC–MS p < 0.05). Metabolite profiles have the potential to act as prognostic markers of clinical outcomes for lung cancer patients. Serial 1H-NMR measurements appear to detect metabolites diagnostic of tumor pathology, while GC–MS provided data better related to prognostic clinical outcomes, possibility due to physiochemical bias related to specific biochemical pathways. These results warrant further study in a larger cohort and with various treatment options.  相似文献   
87.

Background

Studies in mice have shown that PPARα is an important regulator of hepatic lipid metabolism and the acute phase response. However, little information is available on the role of PPARα in human liver. Here we set out to compare the function of PPARα in mouse and human hepatocytes via analysis of target gene regulation.

Methodology/Principal Findings

Primary hepatocytes from 6 human and 6 mouse donors were treated with PPARα agonist Wy14643 and gene expression profiling was performed using Affymetrix GeneChips followed by a systems biology analysis. Baseline PPARα expression was similar in human and mouse hepatocytes. Depending on species and time of exposure, Wy14643 significantly induced the expression of 362–672 genes. Surprisingly minor overlap was observed between the Wy14643-regulated genes from mouse and human, although more substantial overlap was observed at the pathway level. Xenobiotics metabolism and apolipoprotein synthesis were specifically regulated by PPARα in human hepatocytes, whereas glycolysis-gluconeogenesis was regulated specifically in mouse hepatocytes. Most of the genes commonly regulated in mouse and human were involved in lipid metabolism and many represented known PPARα targets, including CPT1A, HMGCS2, FABP1, ACSL1, and ADFP. Several genes were identified that were specifically induced by PPARα in human (MBL2, ALAS1, CYP1A1, TSKU) or mouse (Fbp2, lgals4, Cd36, Ucp2, Pxmp4). Furthermore, several putative novel PPARα targets were identified that were commonly regulated in both species, including CREB3L3, KLF10, KLF11 and MAP3K8.

Conclusions/Significance

Our results suggest that PPARα activation has a major impact on gene regulation in human hepatocytes. Importantly, the role of PPARα as master regulator of hepatic lipid metabolism is generally well-conserved between mouse and human. Overall, however, PPARα regulates a mostly divergent set of genes in mouse and human hepatocytes.  相似文献   
88.
The susceptibility of mammalian spermatozoa to cold shock and freezing damage is due to changes in membrane lipid composition, particularly cholesterol depletion in plasma membrane during cryopreservation. The aim of this study was to investigate the effects of different concentrations of cholesterol-loaded cyclodextrin (CLC) and bovine serum albumin (BSA) on the cryopreservation of goat spermatozoa in tris-citrate egg yolk extender. Semen was collected from four mature goats and divided into seven aliquots prior to cryopreservation. The first aliquot remained untreated and was mixed with TCG, the second aliquot was mixed with TCG and egg yolk (TCGY), third aliquot was mixed with TCGY and 2.5% BSA (TCGYB) and other aliquots were mixed with TCGYB containing 0.75, 1.5, 2.5 and 3 mg/ml CLC. All samples were cryopreserved in straws over liquid nitrogen vapor and sperm motion Kinetics were measured by computer-assisted semen analysis (CASA) (percent motility (MOT), curvilinear velocity (VCL), straight-line velocity (VSL), average path velocity (VAP), linearity (LIN), and amplitude of lateral head displacement (ALH)). Acrosome status and vitality was observed by the triple-stain technique. CLC addition to extender resulted in significant (p < 0.05) enhancement of MOT, STR, and VCL of post-thawing sperm. Post-thawed motility, progressive motility and recovery rate were significantly (p < 0.05) higher in 1.5 mg/ml CLC with 2.5% BSA in TCGY extender compared to other groups. The 1.5 CLC sperm yielded a significant increase in percentage of spermatozoa with intact acrosome (P > 0.05). These results indicate that treating goat sperm with CLC and BSA in TCGY extender improved motility and vitality after freezing and thawing.  相似文献   
89.
Ramos S  Khademi F  Somesh BP  Rivero F 《Gene》2002,298(2):147-157
Members of the RhoBTB subfamily of Rho GTPases are present in vertebrates, Drosophila and Dictyostelium. RhoBTB proteins are characterized by a modular organization, consisting of a GTPase (guanosine triphosphatase) domain, a proline rich region, a tandem of two BTB (Broad-Complex, Tramtrack, and Bric à brac) domains and a C-terminal region of unknown function and might act as docking points for multiple components participating in signal transduction cascades. We have determined the genomic organization and the expression pattern of the three RHOBTB genes of human and mouse. The exon-intron organization of each gene is conserved in three vertebrate species (human, mouse and Fugu). RHOBTB1 and RHOBTB2 have a similar exon-intron organization and are closely related to the single gene encoding the RhoBTB orthologs of two insect species. By contrast, the exon-intron organization of RHOBTB3 differed substantially from that of the two other genes, indicating that this gene arose by a duplication event independent of the one that gave rise to RHOBTB1 and RHOBTB2. RHOBTB1 (located on chromosome 10) and RHOBTB3 (located on chromosome 5) appear ubiquitously expressed. However, they display a differential pattern of expression: RHOBTB1 showed high levels in stomach, skeletal muscle, placenta, kidney and testis, whereas RHOBTB3 was highly expressed in neural and cardiac tissues, pancreas, placenta and testis. RHOBTB2 (located on chromosome 8) showed much lower levels of expression than the other two human RHOBTB genes and it was most abundant in neural tissues. The expression patterns of the human and mouse genes were roughly comparable. All three genes were also detected in fetal tissues, and in a number of cell lines RHOBTB3 predominates. RHOBTB genes are upregulated in some cancer cell lines, suggesting that these proteins might participate in tumorigenesis.  相似文献   
90.
Studies have shown that there is a relationship between zinc levels and depression. Thalassemic patients are at risk of zinc deficiency due to various causes including Desferal injection. The aim of this study, therefore, is to investigate hair zinc levels in thalassemic patients and their association with depression. For the purposes of this survey, 50 patients with major thalassemia between 10-20 years old were selected randomly. The patients' hair zinc concentration was compared with a control group of similarly aged healthy individuals. Simultaneously, their psychological status was evaluated with either the "Beck" or "Marya Kovacs" test (according to age) so that the relation between depression and zinc concentration could be assessed. The mean hair zinc concentration in patients was more than the controls (193.96 +/- 92.4 ppm vs 149.6 +/- 72.21 ppm). Zinc deficiency was present in 10% of the patients, and 52% had some degree of depression. There was a reverse correlation between zinc deficiency and blood transfusion rate (p < 0.05). Also, while there were more incidences of depression among the zinc deficient patients, the difference was not significant. Regarding the high prevalence of depression and insignificant relation to the zinc deficiency in these thalassemic patients, this research suggests the need for further consideration concerning patients' psychological status, the risk factors of zinc deficiency, as well as extended assessment into other causes of depression.  相似文献   
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