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81.
The purpose of this study is to reveal the impacts of biomechanical pressures of heavy working conditions on the upper extremities of young laborers. The study covers the examination of the upper extremities of 104 young laborers in the industrial workshops of Ankara, Turkey regarding bilateral asymmetry. The average age of the laborers was 18.48 +/- 0.61 years. The control group consisted of 102 non-laborers with an average age of 18.39 +/- 0.58 years. The laborers were measured with regard to width of elbows, wrists, and hands, and the length of hands. No significant difference between the groups was observed with the exception of average wrist width. However, while the labor group showed directional asymmetry in all measurements, the non-laborers exhibited directional asymmetry only in hand width and length. Consequently, the study revealed that biomechanical pressures tend to increase directional asymmetry in the upper extremities.  相似文献   
82.
In this study, we aimed at generating 3-dimensional (3D) decellularized bovine spinal cord extracellular matrix-based scaffolds (3D-dCBS) for neural tissue engineering applications. Within this scope, bovine spinal cord tissue pieces were homogenized in 0.1 M NaOH and this viscous mixture was molded to attain 3D bioscaffolds. After resultant bioscaffolds were chemically crosslinked, the decellularization process was conducted with detergent, buffer, and enzyme solutions. Nuclear remnants in the native tissue and 3D-dCBS were determined with DNA content analysis and agarose gel electrophoresis. Afterward, 3D-dCBS were biochemically characterized in depth via glycosaminoglycan (GAG) content, hydroxyproline (HYP) assay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Cellular survival of human adipose-derived mesenchymal stem cells (hAMSCs) on the 3D-dCBS for 3rd, 7th, and 10th days was assessed via MTT assay. Scaffold and cell/scaffold constructs were also evaluated with scanning electron microscopy and histochemical studies. DNA contents for native and 3D-dCBS were respectively found to be 520.76 ± 18.11 and 28.80 ± 0.20 ng/mg dry weight (n = 3), indicating a successful decellularization process. GAG content, HYP assay, and SDS-PAGE results proved that the extracellular matrix was substantially preserved during the decellularization process. In conclusion, it is believed that the novel decellularization method may allow fabricating 3D bioscaffolds with desired geometry from soft nervous system tissues.  相似文献   
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84.

Background and aims

Nickel (Ni) has a critical role in the urea metabolism of plants. This study investigated the impact of seed Ni content along with external Ni supply on the growth, various nitrogen (N) metabolites and N use efficiency (NUE) of soybean plants.

Methods

Soybean plants raised from Ni-poor or Ni-rich seeds were grown in nutrient solution with or without external Ni supply and fed with either urea or nitrate as the sole N source. The changes in growth, leaf chlorophyll levels, Ni and N concentrations of different plant parts, tissue accumulation of various N metabolites and N uptake of soybean as well as NUE and its components were examined.

Results

Nickel starvation reduced the shoot biomass of urea-fed plants by 25 % and the leaf chlorophyll levels by up to 35 %, but nitrate-fed plants were unaffected. Visual toxicity symptoms were not observed in urea-fed plants. Under urea supply, Ni-deficient plants had lower levels of total N, protein and free amino acids in various organs. Root uptake of urea was severely depressed in Ni-deprived plants. Availability of Ni did not have any effect on the NUE of nitrate-fed plants, whereas its deficiency reduced the NUE of urea-fed plants by 30 %. The growth and N nutritional status of urea-fed soybean were significantly improved by high seed Ni reserves as well as external Ni supply.

Conclusion

Adequate Ni supply is required for maximizing the growth, root uptake of urea and NUE of urea-fed plants. Seed Ni reserves contribute significantly to the Ni and thus N nutritional status of soybean.  相似文献   
85.
We developed surface proteome signatures (SPS) for identification of new biomarkers playing a role in cancer drug resistance. SPS compares surface antigen expression of different cell lines by immunocytochemistry of a phage display antibody library directed to surface antigens of HT1080 fibrosarcoma cells. We applied SPS to compare the surface proteomes of two epithelial derived cancer cell lines, MCF7 and NCI/ADR-RES, which is drug resistant because of overexpression of the P-glycoprotein (P-gp) drug efflux pump. Surface proteomic profiling identified CD44 as an additional biomarker that distinguishes between these two cell lines. CD44 immunohistochemistry can distinguish between tumors derived from these lines and predict tumor response to doxorubicin in vivo. We further show that CD44 plays a role in drug resistance, independently of P-gp, in NCI/ADR-RES cells and increases expression of the antiapoptotic protein Bcl-xL. Our findings illustrate the utility of SPS to distinguish between cancer cell lines and their derived tumors and identify novel biomarkers involved in drug resistance.  相似文献   
86.
Consequences of epididymal ligation on prepubertal rats   总被引:1,自引:0,他引:1  
OBJECTIVE: To study prospectively experimental effects of unilateral epididymal obstruction on testis and epididymis histopathologically in prepubertal rats. STUDY DESIGN: Organ weights, mean seminiferous tubule diameter (MSTD), mean ductus epididymis diameter (MDED), mean tubular biopsy scores (MTBS) and histopathology of 21 male albino Wistar rats were compared with the immunostaining affinity of anti-desmin, anti-vimentin, anti-laminin and anti-collagen antibodies. RESULTS: Statistical analysis of mean weight of testes, MTBS, mean epididymal weight, MDED and MSTD was significant. Evaluation of testis and epididymis revealed cellular damage, basal membrane impairment and granulomatous infiltration. CONCLUSION: Histopathologic alterations with MSTD are early indicators for ipsilateral and contralateral injury. Even the presence of criteria such as intactness and cellular integrity does not guarantee there is no sperm leakage or immunologic damage. Therefore the impairment of basal integrity is a switch code in determining spermatogenic failure.  相似文献   
87.
MOTIVATION: Identifier (ID) mapping establishes links between various biological databases and is an essential first step for molecular data integration and functional annotation. ID mapping allows diverse molecular data on genes and proteins to be combined and mapped to functional pathways and ontologies. We have developed comprehensive protein-centric ID mapping services providing mappings for 90 IDs derived from databases on genes, proteins, pathways, diseases, structures, protein families, protein interaction, literature, ontologies, etc. The services are widely used and have been regularly updated since 2006. AVAILABILITY: www.uniprot.org/mappingandproteininformation-resource.org/pirwww/search/idmapping.shtml CONTACT: huang@dbi.udel.edu.  相似文献   
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89.
The aim of this study was to investigate the difference in the serum malondialdehyde (MDA), glutathione (GSH), and nitric oxide (NO) levels between normal and T. gondii-infected patients. To this end, MDA, GSH, and NO levels in the sera of 37 seropositive patients and 40 participants in the control group were evaluated. In Toxoplasma ELISA, IgG results of the patient group were 1,013.0 ± 543.8 in optical density (mean ± SD). A statistically significant difference was found between patients and the control group in terms of MDA, GSH, and NO levels. A decrease in GSH activity was detected, while MDA and NO levels increased significantly. Consequently, it is suggested that the use of antioxidant vitamins in addition to a parasite treatment shall prove useful. The high infection vs control ratio of MDA and NO levels probably suggests the occurrence as a mechanism of tissue damage in cases of chronic toxoplasmosis. Moreover, it is recommended that the patient levels of MDA, GSH, and NO should be evaluated in toxoplasmosis.  相似文献   
90.
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