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21.
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.  相似文献   
22.
Urokinase-type plasminogen activator receptor (uPAR/CD87) together with its ligand, urokinase-type plasminogen activator (uPA), constitutes a proteolytic system associated with tissue remodelling and leucocyte infiltration. uPAR is a member of the glycosyl phosphatidyl inositol (GPI) anchored protein family. The functional role of uPAR comprises fibrinolysis by conversion of plasminogen to plasmin. In addition, uPAR promotes cell adhesion, migration, proliferation, re-organization of the actin cytoskeleton, and angiogenesis. Furthermore, uPAR is involved in prevention of scar formation and is chemoattractant to macrophages and leucocytes. In order to investigate the pathophysiological role of uPAR following human CNS injury we examined necrotic brain lesions resulting from traumatic brain injury (TBI; n = 28) and focal cerebral infarctions (FCI; n = 17) by immunohistochemistry. Numbers of uPAR+ cells and uPAR+ blood vessels were counted. Following brain damage, uPAR+ cells increased significantly within 12 h, reached a maximum after 3-4 days and remained elevated until later stages. uPAR was expressed by infiltrating granulocytes, activated microglia/macrophages and endothelial cells. Numbers of uPAR+ vessels increased in parallel subsiding earlier following FCI than post TBI. The restricted, lesion-associated accumulation of uPAR+ cells in the brain parenchyma and upregulated expression by endothelial cells suggests a crucial role for the influx of inflammatory cells and blood-brain barrier (BBB) disturbance. Through a failure in BBB function, uPAR participates in formation of brain oedema and thus contributes to secondary brain damage. In conclusion, the study defines the localization, kinetic course and cellular source of uPAR as a potential pharmacological target following human TBI and FCI.  相似文献   
23.
BACKGROUND: Untreated chronic critical leg ischaemia (CLI) usually leads to an amputation or death of a patient. Surgical and endovascular interventions may improve arterial flow. Long infrainguinal reconstruction may be the most useful method for preventing amputations. The value of different reconstruction methods was assessed by their impact on amputation incidence. METHODS: A nationwide 2-year analysis of the incidence of major amputations and reconstructions for CLI was done in Finland (population 5.1 million). Incidences were compared in hospital regions with more than 150 000 inhabitants. RESULTS: The overall amputation incidence was 216 per million inhabitants per year. The corresponding incidence of arterial reconstructions was 203 per million inhabitants per year. There were large variations in the incidence of amputations and reconstructions; 20-fold differences in infrapopliteal surgical reconstructions and 30-fold differences in endovascular procedures were found. There was a correlation between a high incidence of infrapopliteal surgical reconstructions and a low incidence of amputations. This correlation was found for below-knee amputations only. CONCLUSION: These results suggest that long surgical reconstructions improving perfusion directly to the ischaemic tissue can improve leg salvage.  相似文献   
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People turn to many sources for recommendations on nutrition and they are often persuaded to follow the dietary guidelines of “self-proclaimed specialists,” sometimes with harmful consequences. Dr Grossman believes that primary care physicians are the best providers of nutrition advice. In this special article, he offers a commonsense guide to nutrition with an approach that is relaxed but informative. We at POSTGRADUATE MEDICINE recognize that his claims are somewhat polemic and that he may have oversimplified some issues, but we consider these views important and appropriate to present to our readers.—R.B.H.  相似文献   
26.
Luther  B.  Mamopoulos  T. A.  Schott  P.  Touloumtzidis  A.  Kröger  K.  Katoh  M. 《Notfall & Rettungsmedizin》2017,20(4):299-304
Notfall + Rettungsmedizin - Die Mortalität der akuten mesenterialen Ischämie ist nach wie vor sehr hoch. Auch bei einem standardisierten viszeral- und gefäßchirurgischen...  相似文献   
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Background

The relationship between traffic-related air pollution (TRAP) and risk factors for cardiovascular disease needs to be better understood in order to address the adverse impact of air pollution on human health.

Objective

We examined associations between roadway proximity and traffic exposure zones, as markers of TRAP exposure, and metabolic biomarkers for cardiovascular disease risk in a cohort of patients undergoing cardiac catheterization.

Methods

We performed a cross-sectional study of 2,124 individuals residing in North Carolina (USA). Roadway proximity was assessed via distance to primary and secondary roadways, and we used residence in traffic exposure zones (TEZs) as a proxy for TRAP. Two categories of metabolic outcomes were studied: measures associated with glucose control, and measures associated with lipid metabolism. Statistical models were adjusted for race, sex, smoking, body mass index, and socioeconomic status (SES).

Results

An interquartile-range (990 m) decrease in distance to roadways was associated with higher fasting plasma glucose (β = 2.17 mg/dL; 95% CI: –0.24, 4.59), and the association appeared to be limited to women (β = 5.16 mg/dL; 95% CI: 1.48, 8.84 compared with β = 0.14 mg/dL; 95% CI: –3.04, 3.33 in men). Residence in TEZ 5 (high-speed traffic) and TEZ 6 (stop-and-go traffic), the two traffic zones assumed to have the highest levels of TRAP, was positively associated with high-density lipoprotein cholesterol (HDL-C; β = 8.36; 95% CI: –0.15, 16.9 and β = 5.98; 95% CI: –3.96, 15.9, for TEZ 5 and 6, respectively).

Conclusion

Proxy measures of TRAP exposure were associated with intermediate metabolic traits associated with cardiovascular disease, including fasting plasma glucose and possibly HDL-C.

Citation

Ward-Caviness CK, Kraus WE, Blach C, Haynes CS, Dowdy E, Miranda ML, Devlin RB, Diaz-Sanchez D, Cascio WE, Mukerjee S, Stallings C, Smith LA, Gregory SG, Shah SH, Hauser ER, Neas LM. 2015. Association of roadway proximity with fasting plasma glucose and metabolic risk factors for cardiovascular disease in a cross-sectional study of cardiac catheterization patients. Environ Health Perspect 123:1007–1014; http://dx.doi.org/10.1289/ehp.1306980  相似文献   
29.

Background

Undergraduate nursing students may not have the opportunity to assess and intervene with a patient diagnosed with schizophrenia during their clinical rotation. Provision of a standardized patient simulation experience affords students this opportunity in a safe setting without risk to the patient or student.

Methods

A quasi-experimental design was utilized to explore the impact of the addition of a standardized patient simulation scenario depicting a patient with a diagnosis of schizophrenia on undergraduate nursing student knowledge and perceived competency.

Results

The mean values for perceived competence and knowledge increased significantly over the three time periods (p?<?0.001).

Conclusion

The results suggest that incorporating SP simulation into the undergraduate psychiatric mental health nursing course has the potential to enhance both knowledge and perceived competency of students in caring for patients diagnosed with schizophrenia and ultimately promote better healthcare outcomes.  相似文献   
30.
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