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511.
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Hayward  CP; Rivard  GE; Kane  WH; Drouin  J; Zheng  S; Moore  JC; Kelton  JG 《Blood》1996,87(12):4967-4978
Multimerin is a massive soluble, multimeric protein found in platelets and endothelial cells. Recent studies identified multimerin as a specific coagulation factor V binding protein, complexed with platelet, but not plasma, factor V. These findings led us to investigate individuals with inherited factor V deficiencies for possible multimerin abnormalities. Platelet proteins were evaluated using immunoassays, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, immunoprecipitation, and direct binding studies. Patients with factor V Quebec, a disorder with abnormal platelet factor V, had a quantitative deficiency in multimerin (n = 11 tested; mean, 12.5%; range, 5% to 27% of the normal pool; normal range, 45% to 214%) with a normal multimer pattern. Quantitative and qualitative abnormalities were detected in their platelet factor V. An unrelated patient who was deficient in platelet and plasma factor V had normal platelet multimerin. The levels of platelet beta- thromboglobulin, von Willebrand factor, thrombospondin, and fibrinogen antigen were normal in the factor V Quebec patients. However, proteins with abnormal mobility were detected in their platelet lysate and releasate, and their platelet thrombospondin, von Willebrand factor, and fibrinogen showed evidence of proteolytic degradation. Platelet counts of the factor V Quebec patients ranged from mildly thrombocytopenic to low normal (mean, 159 x 10(9)/L; range, 104 to 198 x 10(9)/L). In addition, their platelets failed to aggregate in response to 6 to 10 micromol/L epinephrine despite normal numbers of platelet alpha 2-adrenergic receptors. These data indicate that patients with factor V Quebec have an inherited bleeding disorder distinct from other platelet disorders and associated with multiple abnormalities, including multimerin deficiency, abnormal platelet factor V, thrombospondin, von Willebrand factor, and fibrinogen, and an epinephrine aggregation defect.  相似文献   
514.
Of 1,036 children with newly diagnosed non-T, non-B acute lymphoblastic leukemia (ALL) and a demonstrated cytogenetic abnormality treated on the frontline Pediatric Oncology Group (POG) therapeutic trial 8602, there were 33 patients with trisomy 21 as the sole abnormality. Of these 33, 14 had Down syndrome (DS). Although the non-DS (NDS) trisomy 21 cases tended to be older than the DS cases, there were no other significant differences in clinicobiologic features nor in treatment outcomes between the DS and NDS groups, nor between the entire trisomy 21 group and the other chromosome abnormality group. Among NDS patients with +21 and one additional abnormality, +X, +16, -20, and structural abnormalities involving 6q or 12p were common findings. Kaplan-Meier event-free survival (EFS) curves showed a 4-year EFS of 80% (SE, 12%) in NDS trisomy 21 cases, 71% (SE, 22%) in DS cases with trisomy 21 as the sole abnormality, and 69% (SE, 2%) in cases with other chromosome abnormalities. Trisomy 21 as a sole acquired abnormality in NDS patients suggests a good prognosis.  相似文献   
515.

INTRODUCTION

Between 4% and 13% of patients with operable pancreatic malignancy are found unresectable at the time of surgery. Double bypass is a good option for fit patients but it is associated with high risk of postoperative complications. The aim of this study was to identify pre-operatively which patients undergoing double bypass are at high risk of complications and to assess their long-term outcome.

METHODS

Of the 576 patients undergoing pancreatic resections between 2006 and 2011, 50 patients who underwent a laparotomy for a planned pancreaticoduodenectomy had a double bypass procedure for inoperable disease. Demographic data, risk factors for postoperative complications and pre-operative anaesthetic assessment data including the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM) and cardiopulmonary exercise testing (CPET) were collected.

RESULTS

Fifty patients (33 men and 17 women) were included in the study. The median patient age was 64 years (range: 39–79 years). The complication rate was 50% and the in-hospital mortality rate was 4%. The P-POSSUM physiology subscore and low anaerobic threshold at CPET were significantly associated with postoperative complications (p=0.005 and p=0.016 respectively) but they were unable to predict them. Overall long-term survival was significantly shorter in patients with postoperative complications (9 vs 18 months). Postoperative complications were independently associated with poorer long-term survival (p=0.003, odds ratio: 3.261).

CONCLUSIONS

P-POSSUM and CPET are associated with postoperative complications but the possibility of using them for risk prediction requires further research. However, postoperative complications following double bypass have a significant impact on long-term survival and this type of surgery should therefore only be performed in specialised centres.  相似文献   
516.
已证实雷洛昔芬在骨和胆固醇代谢中起雌激素激动剂的作用,而在乳腺和子宫起雌激素拈抗剂的作用:本文研究雷洛昔芬是否具有雌激素激动剂作用,是否能预防冠状动脉粥样硬化,并与传统的结合雌激素治疗的疗效相比较。卵巢切除(即手术绝经)的短尾猴,喂食会导致冠状动脉粥样硬化的食物,然后分别以安慰剂、雷洛昔芬每日1mg、  相似文献   
517.
Irish men and women are at equal risk of developing Crohn's disease. Age at diagnosis (12--mean 30.5-75 yr) and duration of symptoms before diagnosis (1--mean 35.7-444 months) are similar to those for Crohn's disease in other countries. The proportion of patients with macroscopic involvement of the large bowel at diagnosis (68%) is increasing and this is probably a true increase. At the same time the incidence of perianal disease is probably decreasing. Extraintestinal manifestations probably occur more frequently than previously recognized. Crohn's disease and psoriasis, which occurred in 7% of the patients, are probably associated disorders.  相似文献   
518.
Birth prior to 37 completed weeks of gestation is referred to as preterm (PT). Premature newborns are at increased risk of developing infections as neonatal immunity is a developing structure. Monocytes, which are key players after birth, activate inflammasomes. Investigations into the identification of innate immune profiles in premature compared to full-term infants are limited. Our research includes the investigation of monocytes and NK cells, gene expression, and plasma cytokine levels to investigate any potential differences among a cohort of 68 healthy PT and full-term infants. According to high-dimensional flow cytometry, PT infants have higher proportions of CD56+/−CD16+NK cells and immature monocytes, and lower proportions of classical monocytes. Gene expression revealed lower proportions of inflammasome activation after in vitro monocyte stimulation and the quantification of plasma cytokine levels expressed higher concentrations of alarmin S100A8. Our findings suggest that PT newborns have altered innate immunity and monocyte functional impairment, and pro-inflammatory plasmatic profile. This may explain PT infants’ increased susceptibility to infectious disease and should pave the way for novel therapeutic strategies and clinical interventions.  相似文献   
519.

Background/Aims

The prevalence of dental injuries in patients with facial fractures is relevant. Epidemiologically, dental trauma in association with facial fractures generally affects the age group between 20 and 40 years old, with a higher prevalence in males. The aim of this retrospective study was to identify the incidence and etiology of dental trauma associated with facial fractures over a 10-year period.

Methods

From January 2009 to April 2019, among 381 patients with facial fractures, 353 were included in this study. Age, gender, trauma etiology, injured teeth and dental treatment were investigated.

Results

From 353 patients, with a mean age of 49.7 ± 19.9 years, 247 (70%) were males and 106 (30%) were females. Accidental falls were the most common type of injury (n = 118, 33.4%), followed by road accidents (n = 90, 25.5%), assaults (n = 60, 17%) and sports trauma (n = 37, 10.5%). Fifty-five subjects (15.60%) had dental injuries associated with facial fractures. Of the 145 teeth involved, 48 (33.1%) were diagnosed with luxation, 22 teeth (15.2%) were avulsed, 11 teeth (7.5%) suffered a concussion and there were 10 (6.8%) alveolar wall fractures.Uncomplicated enamel-dentin fracture was the more frequent hard tissue injury (n = 21, 14.5%), followed by complicated crown-root fracture (n = 10, 6.9%), infraction (n = 8, 5.5%), enamel fracture (n = 3, 2%) and complicated enamel-dentin fracture (n = 3, 2%). There was a peak in incidence between 21 and 40 years (42%). Males had a significantly higher risk of facial fractures with dental injury (75%). Maxillary incisors and canines (62.8%) were the most affected teeth.

Conclusions

There was a high prevalence of dental injuries associated with facial fractures. Maxillary incisors were the most injured teeth, with a higher prevalence in males.  相似文献   
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