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991.
Breast cancer is one of the most prevalent malignancies among women around the world. RAS proteins require posttranslational modifications, including protein prenylation for proper membrane localization and signaling. Regulation of RAS signaling via specific and novel pharmacological inhibitors is a potentially novel therapeutic approach in breast cancer therapy. This review summarizes the recent knowledge about the clinical value of RAS prenylation pharmacological inhibitors in breast cancer treatment.  相似文献   
992.
Transitional cell carcinoma (TCC), which is the most common type of bladder cancer, shows resistance to chemotherapeutic agents due to the overexpression of drug efflux pumps. In this study, the effects of feselol, a sesquiterpene coumarin extracted from Ferula badrakema, on cisplatin cytotoxicity were investigated in 5637 cells, a TCC subline. Cell viability and DNA lesion were evaluated by thiazolyl blue tetrazolium bromide and comet assays, respectively. Feselol had no significant cytotoxic effect in 5637 cells but at 32 microg/mL it increased the cytotoxicity of 1 microg/mL cisplatin by 37% after 24 h. Furthermore, the comet assay revealed that DNA damage induced by cisplatin in 5637 cells is enhanced by 31% when used in combination with feselol. Therefore, feselol might be considered as an effective reversal agent for future in vivo and clinical studies.  相似文献   
993.
994.
The brine shrimp, Artemia is the dominant macrozooplankton present in many hypersaline environments. Artemia urmiana is the only macroscopic organism in Urmia Salt Lake (Iran), and the high salinity of the lake makes it a suitable environment for halophilic archaea too. Because of common environment for Artemia and extreme halophiles; this investigation is concentrated on studying the relationship between Artemia and halophilic archaea in Urmia Lake. In this study first the procedure of arhaea isolation was done. Then, isolated strains were sub-cultured and DNA was extracted and amplified by PCR using specific primers for amplifying archaeal 16S rRNA. The amplified archeal DNA fragments were purified, and sequenced. 16S rRNA sequences were compared to known sequences using the NCBI BLAST program. Sequences relating to Halorubrum, Haloarcula and Halobacterium species were identified in Urmia Salt Lake water and Artemia adults and the phylogenetic tree of different species was constructed. Only Halorubrum species were present in association with Artemia. They belong to Halobacteriaceae family of archeae which are isolated from different salt lakes in different parts of world and we could show their existence in adult Artemia, another organism living in hypersaline enviroments.  相似文献   
995.
The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), has worldwide distribution and found wherever cruciferous plants is grown. In this study, fluctuations of parasitism rate of P. xylostella by Oomyzus sokolowskii on different cauliflower cultivars were evaluated in the field during 2011 at research station of the Shahed University (South of Tehran). This investigation was conducted on the eight cauliflower cultivars including Smilla, Snow mystique, White cloud, Buris, Galiblanka, Snow crown, SG and Tokita in a randomised complete block design with five replications. The results showed that density of total larva and pupa of the diamondback moth on Buris and Snow crown cultivars is lower than other cultivars. The highest and the lowest percentage of parasitism by O. sokolowskii was observed on Buris cultivar (7.93?±?0.91%) and SG cultivar (1.28?±?0.36%) during the season, respectively.  相似文献   
996.
Biological Trace Element Research - To observe and compare the effects of healthy instruction and Zhiqi granules on lead, calcium, iron, and zinc levels in serum of children with moderately...  相似文献   
997.
The paper analyzes the connection between microstructure of the osteonal cortical bone and its overall elastic properties. The existing models either neglect anisotropy of the dense tissue or simplify cortical bone microstructure (accounting for Haversian canals only). These simplifications (related mostly to insufficient mathematical apparatus) complicate quantitative analysis of the effect of microstructural changes – produced by age, microgravity, or some diseases – on the overall mechanical performance of cortical bone. The present analysis fills this gap; it accounts for anisotropy of the dense tissue and uses realistic model of the porous microstructure. The approach is based on recent results of Sevostianov et al. (2005) and Saadat et al. (2012) on inhomogeneities in a transversely-isotropic material. Bone?s microstructure is modeled according to books of Martin and Burr (1989), Currey (2002), and Fung (1993) and includes four main families of pores. The calculated elastic constants for porous cortical bone are in agreement with available experimental data. The influence of each of the pore types on the overall moduli is examined.  相似文献   
998.

Background

Anticoagulation therapy is usually required in patients with chronic kidney disease (CKD) for treatment or prevention of thromboembolic diseases. However, this benefit could easily be offset by the risk of bleeding.

Objectives

To determine the incidence of adverse outcomes of anticoagulants in hospitalized patients with CKD, and to compare the rates of major bleeding events between the unfractionated heparin (UFH) and enoxaparin users.

Methods

One year prospective observational study was conducted in patients with CKD stages 3 to 5 (estimated GFR, 10–59 ml/min/1.73 m2) who were admitted to the renal unit of Dubai Hospital. Propensity scores for the use of anticoagulants, estimated for each of the 488 patients, were used to identify a cohort of 117 pairs of patients. Cox regression method was used to estimate association between anticoagulant use and adverse outcomes.

Results

Major bleeding occurred in 1 in 3 patients who received anticoagulation during hospitalization (hazard ratio [HR], 4.61 [95% confidence interval [CI], 2.05–10.35]). Compared with enoxaparin users, patients who received anticoagulation with unfractionated heparin had a lower mean [SD] serum level of platelet counts (139.95 [113]×103/µL vs 205.56 [123] ×103/µL; P<0.001), and had a higher risk of major bleeding (HR, 4.79 [95% CI, 1.85–12.36]). Furthermore, compared with those who did not receive anticoagulants, patients who did had a higher in-hospital mortality (HR, 2.54 [95% CI, 1.03–6.25]); longer length of hospitalization (HR, 1.04 [95% CI, 1.01–1.06]); and higher hospital readmission at 30 days (HR, 1.79 [95% CI, 1.10–2.91]).

Conclusions

Anticoagulation among hospitalized patients with CKD was significantly associated with an increased risk of bleeding and in-hospital mortality. Hence, intensive monitoring and preventive measures such as laboratory monitoring and/or dose adjustment are warranted.  相似文献   
999.
Elsewhere in this book the important role of creatine kinase and its metabolites in high energy phosphate metabolism and transport in muscle cells has been reviewed. The emphasis of this review article is mainly on the compartmentalized catalytic activity of adenylate kinase in relation to creatine kinase isoenzymes, and other enzymes of energy production and utilization processes in muscle cells. At present the role of adenylate kinase is considered simply to equilibrate the stores of adenine nucleotides. Recent studies by us and others, however, suggest an entirely new view of the metabolic importance of adenylate kinase in muscle function. This view offers a closer interaction between adenylate kinase and creatine kinase, in the process of energy production (at mitochondrial and glycolytic sites), and energy utilization (at myofibrillar sites and perhaps other sites such as sarcoplasmic reticular, sarcolemmal membrane, etc.), thus being an integral part of the high energy phosphate transport system.This review article opens up the opportunity to further examine the metabolism of adenine nucleotides and their fluxes through the adenylate kinase system in intact muscle cells. Using an intact system, having a preserved integrity of their compartmentalized enzymes and substrates, is essential in clarifying the exact role of adenylate kinase in high energy phosphate metabolism in muscle cells.  相似文献   
1000.
The signal transduction pathway for insulin-mediated activation of sarcolemmal Na+–Ca2+ exchange was examined. Insulin stimulated Na+–Ca2+ exchanger activity in a dose-dependent manner, with the EC50 being about 0.7 U/l. The insulin effect was blocked by the protein kinase inhibitor, staurosporine, indicating possible involvement of a protein kinase in insulin action. Also, the relationship between the insulin effect and activation of a G protein, was examined by testing the effects of 5 guanylyl imidodiphosphate (Gpp(NH))p) on Na+–Ca2+ exchange in, the presence and absence of insulin. When exchanger activity was assayed at a calcium concentration of 40 M, insulin alone had no effect whereas ATP and Gpp(NH)p increased exchanger activity. However, insulin responsiveness was restored in vesicles preloaded with either ATP or Gpp(NH)p, suggesting that insulin may act through a combination of G protein coupling and protein phosphorylation to enhance Na+–Ca2+ exchanger activity. We conclude that calcium overload in the diabetic heart may involve a defect in acute activation of the exchanger by insulin.  相似文献   
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