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161.
162.
Johannes N. Lodders Satyesh Parmar Niki LM. Stienen Timothy J. Martin K. Hakki Karagozoglu Martijn W. Heymans Baljeet Nandra Tymour Forouzanfar 《Medicina oral, patología oral y cirugía bucal》2015,20(6):e744-e750
Background
The aims of the study were 1) to evaluate the incidence and types of postoperative complications after ablative oral cancer surgery with primary free flap reconstruction and 2) identify prognostic variables for postoperative complications.Material and Methods
Desired data was retrieved from a computer database at the department of Oral and Maxillofacial Department, Queen Elisabeth hospital Birmingham, United Kingdom, between June 2007 and October 2012. Logistic regression was used to study relationships between preoperative variables and postoperative outcomes.Results
The study population consisted 184 patients, comprising 189 composite resections with reconstruction. Complications developed in 40.2% of the patients. Three patients (1.6%) died, 11.1% returned to the operating room, 5.3% developed donor site complications and 6.9% flap complications of which 3.2% total flap failure. In the multivariable analysis systemic complications were associated with anaesthesia time and hospital stay with red cell transfusion.Conclusions
A significant proportion of the patients with primary free flap reconstructions after oral cancer surgery develops postoperative complications. Prolonged anaesthesia time and red cell transfusion are possible predictors for systemic complications and hospital stay respectively. Preoperative screening for risk factors is advocated for patient selection and to have realistic information and expectations. Key words:Free flap, complications, oral cancer, risk factors, reconstruction. 相似文献163.
The Development of a Consensus Statement on Normal Physiologic Birth: A Modified Delphi Study 下载免费PDF全文
Holly Powell Kennedy CNM PhD Melissa Cheyney PhD CPM LDM Mary Lawlor CPM LM NHCM MA Suzy Myers LM CPM MPH Kerri Schuiling CNM PhD Tanya Tanner CNM MS MBA and the Normal Birth Task Force of the American College of Nurse‐Midwives the Midwives Alliance of North America and the National Association of Certified Professional Midwives 《Journal of Midwifery & Women's Health》2015,60(2):140-145
164.
165.
Natasha J Verbakel Maaike Langelaan Theo JM Verheij Cordula Wagner Dorien LM Zwart 《The British journal of general practice》2015,65(634):e319-e329
Background
A constructive safety culture is essential for the successful implementation of patient safety improvements.Aim
To assess the effect of two patient safety culture interventions on incident reporting as a proxy of safety culture.Design and setting
A three-arm cluster randomised trial was conducted in a mixed method study, studying the effect of administering a patient safety culture questionnaire (intervention I), the questionnaire complemented with a practice-based workshop (intervention II) and no intervention (control) in 30 general practices in the Netherlands.Method
The primary outcome, the number of reported incidents, was measured with a questionnaire at baseline and a year after. Analysis was performed using a negative binomial model. Secondary outcomes were quality and safety indicators and safety culture. Mixed effects linear regression was used to analyse the culture questionnaires.Results
The number of incidents increased in both intervention groups, to 82 and 224 in intervention I and II respectively. Adjusted for baseline number of incidents, practice size and accreditation status, the study showed that practices that additionally participated in the workshop reported 42 (95% confidence interval [CI] = 9.81 to 177.50) times more incidents compared to the control group. Practices that only completed the questionnaire reported 5 (95% CI = 1.17 to 25.49) times more incidents. There were no statistically significant differences in staff perception of patient safety culture at follow-up between the three study groups.Conclusion
Educating staff and facilitating discussion about patient safety culture in their own practice leads to increased reporting of incidents. It is beneficial to invest in a team-wise effort to improve patient safety. 相似文献166.
167.
We have used succinylacetone (4,6-dioxoheptanoic acid), a specific inhibitor of delta-aminolevulinic acid dehydrase, to gain insight into the defect in iron metabolism in the Belgrade anemia. The Belgrade rat has an inherited microcytic, hypochromic anemia associated with poor iron uptake into developing erythroid cells. Succinylacetone inhibits heme synthesis, leading to nonheme iron accumulation in mitochondria and cytosol of normal reticulocytes. When succinylacetone is used to inhibit Belgrade heme synthesis, iron from diferric transferrin does not accumulate in the stromal fraction that contains mitochondria, nor does 59Fe accumulate in the nonheme cytosolic fraction. Hence, the defect in the Belgrade rat reticulocyte occurs in the endocytic vesicle or in a step subsequent to iron transit from the vesicle but before the nonheme cytosolic or mitochondrial iron fractions. Therefore, the mutation affects either the release of iron from transferrin or iron transport from the vesicle to the mitochondrion. 相似文献
168.
Human mast cells synthesize new granules during recovery from degranulation. In vitro studies with mast cells purified from human lungs 总被引:3,自引:0,他引:3
Secretory cells undergoing release and recovery events related to constitutive and/or stimulus-initiated secretion might be expected to undergo distinctive changes in morphology as well. We studied the release and recovery events of human mast cell secretion stimulated by antibody to immunoglobulin E. We used enzymatically digested mast cells from human lung specimens further purified by countercurrent centrifugation elutriation. Release kinetics were like those reported for isolated human lung mast cells. In two complete kinetic experiments we restudied these early release patterns (0 to 30 minutes). Mast cells, either stimulated or controls, were then cultured and sampled for electronmicroscopic studies at periodic intervals (3 to 48 hours). We describe events of the late recovery period here, although some overlap with processes seen in early recovery samples occurred. Mast cells that released nearly all their cytoplasmic granules and exteriorized the containers, eg, granule-channel membranes, underwent progressive enlargement of Golgi structures and development of numerous small cytoplasmic vesicles and small, membrane-bound granules filled with particulate and dense content. Ultimately, new mature cytoplasmic granules of all substructural patterns occurred. Nuclear blast changes and expansion of cytoplasmic mass accompanied this period of new granule synthesis. Mixed recovery patterns were present in individual cells. These represented the morphological expression of a variety of recovery events. Thus, some cells showed a combination of channel recovery and remodeling to form new granule containers within which condensation of content produced crystalline patterns, as well as synthesis of new granules, as described here. This morphological versatility resulted in multiple mast cell morphological phenotypes during these release and recovery processes. 相似文献
169.
The erythrocytes of the newborn infant have many properties that distinguish them from those of adults, and their membranes are also different from those of adult erythrocytes. We compared the ability of adult and neonatal RBCs to undergo endocytosis on exposure to drugs. Using a quantitative method, we showed that neonatal erythrocytes undergo a greater degree of endocytosis than do adult RBCs in response to primaquine, vinblastine, and chlorpromazine, and are sensitive to lower concentrations of the drugs. Some forms of drug-induced endocytosis are red cell age-dependent; when RBCs were separated by density gradient centrifugation, the membranes of the younger, less dense populations of both the neonatal and adult RBCs were capable of more extensive internalization than those of the denser, older RBCs. Neonatal RBCs of a given density undergo more endocytosis than do adult RBCs of the same density, suggesting that the membrane of the neonatal RBC is less stable and capable of more of the reorganization reflected in endocytosis than is the adult RBC membrane. 相似文献
170.
BCL-6 expression during B-cell activation 总被引:14,自引:6,他引:14
Translocations involving the BCL-6 gene are common in the diffuse large cell subtype of non-Hodgkin's lymphoma. Invariably, the BCL-6 coding region is intact, but its 5' untranslated region is replaced with sequences from the translocation partner. The present study shows that BCL-6 expression is regulated in lymphocytes during mitogenic stimulation. Resting B and T lymphocytes contain high levels of BCL-6 mRNA. Stimulation of mouse B cells with anti-IgM or IgD antibodies, bacterial lipopolysaccharide, phorbol 12-myristate 13-acetate plus ionomycin, or CD40 ligand led to a five-fold to 35-fold decrease in BCL- 6 mRNA levels. Similar downregulation of BCL-6 mRNA was seen in human B cells stimulated with Staphylococcus aureus plus interleukin-2 or anti- IgM antibodies and in human T lymphocytes stimulated with phytohemagglutinin. BCL-6 mRNA levels began to decrease 8 to 16 hours after stimulation, before cells entered S phase. Although polyclonal activation of B cells in vitro invariably decreased BCL-6 MRNA expression, activated B cells from human germinal centers expressed BCL- 6 mRNA at levels comparable to the levels in resting B cells. Despite these similar mRNA levels, BCL-6 protein expression was threefold to 34- fold higher in germinal center B cells than in resting B cells, suggesting that BCL-6 protein levels are controlled by translational or posttranslational mechanisms. These observations suggest that the germinal center reaction provides unique activation signals to B cells that allow for continued, high-level BCL-6 expression. 相似文献