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Silver nanoparticles (SNP) are used in many pharmaceutical, cosmetic, and industrial products already available in the market. Although they are considered relatively safe, many toxic and pathological alterations in different organs including immune organs were reported after SNP administration. In this study, 10-week-old male mice (n = 20) were divided into two groups. Ten mice received greenly synthesized gelatin-coated silver nanoparticles in a dose of 10 mg/kg body weight for five consecutive days while the other 10 received 0.5 ml of distilled water daily for 5 days and kept as control. At the sixth day, all mice were sacrificed; blood and tissue samples were collected and prepared for pathological analysis. Liver and kidney lesions were in the form of degenerative and inflammatory changes. Interestingly, the immune organs were drastically affected by SNP treatment. Severe hyperplasia of the Peyer’s patches was noticed in the intestines of intoxicated animals both in gross and microscopic examination. Spleen was enlarged and showed large number of megakaryocytes. The particles were encountered in membrane-bound phagosomes inside macrophages in different organs like lungs and spleen. Blood picture complied to morphological findings with an increase in monocytes and eosinophils accompanied by drop in the platelets count in the intoxicated animals.  相似文献   
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Pasteurellosis is one of the most important respiratory diseases facing economically valuable farm animals such as poultry, rabbit, cattle, goats and pigs. It causes severe economic loss due to its symptoms that range from primary local infection to fatal septicemia. Pasteurella multocida is the responsible pathogen for this contagious disease. Chemotherapeutic treatment of Pasteurella is expensive, lengthy, and ineffective due to the increasing antibiotics resistance of the bacterium, as well as its toxicity to human consumers. Though, biosecurity measures played a role in diminishing the spread of the pathogen, the immunization methods were always the most potent preventive measures. Since the early 1950s, several trials for constructing and formulating effective vaccines were followed. This up-to-date review classifies and documents such trials. A section is devoted to discussing each group benefits and defects.  相似文献   
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AimEvaluate the anti-erythrocyte and anti-HLA immunization rates in hemoglobinopathies.Patients and methodsCross-sectional study (October 2009–March 2010) on 83 patients followed for hemoglobinopathies. The irregular antibodies research is realized by two techniques: indirect Coombs and enzymatic technique on gel cards. The search for anti-HLA class I antibodies is done by complement dependent lymphocytotoxicity.ResultsThe mean age was 30 years (14–64 years), the sex ratio M/F is 0.84. Our series included 42 cases of sickle cell disease (29 homozygous sickle cell anemia and 13 sickle-thalassemia) and 41 cases of thalassemia syndromes (26 major and 15 intermediate). The anti-erythrocyte alloimmunization rate is 10.84% without difference between thalassemia syndromes and sickle cell disease. The autoimmunization rate (22.89%) is higher in thalassemia syndromes (41.46%) than in the sickle cell disease (7.14%) (P < 0.001). The anti-HLA immunization rate is 31.6% without difference between thalassemia syndromes and sickle cell disease. The young age, transfusion at a young age and the total number of transfusions are the factors that increase the risk of anti-erythrocyte autoimmunization. No clinicobiological parameter does influence the anti-erythrocyte and anti-HLA alloimmunization. There is no significant association between anti-erythrocyte and anti-HLA immunization.ConclusionThe erythrocyte and anti-HLA anti-immunization rates are high in our series. Preventive strategy is needed to ensure optimal blood safety.  相似文献   
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Background

The initiation of end of life care in an acute stroke context should be focused on those patients and families with greatest need. This requires clinicians to synthesise information on prognosis, patterns (trajectories) of dying and patient and family preferences. Within acute stroke, prognostic models are available to identify risks of dying, but variability in dying trajectories makes it difficult for clinicians to know when to commence palliative interventions. This study aims to investigate clinicians’ use of different types of evidence in decisions to initiate end of life care within trajectories typical of the acute stroke population.

Methods/design

This two-phase, mixed methods study comprises investigation of dying trajectories in acute stroke (Phase 1), and the use of clinical scenarios to investigate clinical decision-making in the initiation of palliative care (Phase 2). It will be conducted in four acute stroke services in North Wales and North West England. Patient and public involvement is integral to this research, with service users involved at each stage.

Discussion

This study will be the first to examine whether patterns of dying reported in other diagnostic groups are transferable to acute stroke care. The strengths and limitations of the study will be considered. This research will produce comprehensive understanding of the nature of clinical decision-making around end of life care in an acute stroke context, which in turn will inform the development of interventions to further build staff knowledge, skills and confidence in this challenging aspect of acute stroke care.
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Despite operator experience and improved catheter technology, acute vessel closure is inherently associated with percutaneous transluminal coronary angioplasty (PTCA) of complex lesions. This case study describes a patient who developed an occlusive dissection post PTCA at the bifurcation of the left anterior descending artery (LAD) and its diagonal branch. The “T”-shaped wiktor stent placement immediately re-establishes full flow, obviating the necessity for emergent surgery. © 1996 Wiley-Liss, Inc.  相似文献   
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To better characterize the role of the lipoprotein lipase (LPL) gene in the determination of triglyceride levels in healthy subjects, a study was performed in 193 nuclear families (384 parents, means age = 42.0 ± 5.2 years; 399 offspring, mean age = 14.6 ± 4.3 years) volunteering to have a free health checkup examination. The pattern of familial resemblance was compatible with a zero correlation between spouses, a weak father-offspring correlation (0.099 ± 0.054; P < 0.07), and significant mother-offspring (0.235 ± 0.053; P < 10−4) and sib-sib (0.294 ± 0.064; P < 10−4) correlations. Associations of triglyceride levels with the LPL HindIII and PvuII polymorphisms were investigated by a familial measured genotype analysis, specifying sex- and age-dependent polymorphism effects. The effects associated with both polymorphisms were significant only in fathers, the H+ and P+ alleles being associated with raised triglyceride levels. The HindIII and PvuII polymorphisms explained 3.5% and 3%, respectively, of the variability of triglycerides in fathers. The relationship was weakened after prior adjustment on body mass index, but remained significant for PvuII. Because of the lack of effect in mothers and offspring, the polymorphisms did not contribute to the covariance of triglyceride levels in relatives. In conclusion, this family study showed a weak relationship of the HindIII and PvuII polymorphisms to plasma triglyceride levels in young healthy male subjects. The effects detectable only in fathers suggest a possible modulation of the LPL expression by hormonal or lifestyle factors. © 1996 Wiley-Liss, Inc.  相似文献   
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