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51.
急性呼吸窘迫综合征(ARDS)是临床上常见的以顽固性低氧为表现的呼吸功能不全或衰竭的综合征,肺不均一性是其主要病理生理特点。传统观点认为,保留ARDS患者自主呼吸有助于改善全身氧合。但是近年来发现,对于重度ARDS患者,保留患者自主呼吸会加重肺损伤,过强的自主呼吸会导致重度ARDS患者跨肺压升高、肺内气体摆动、肺水肿加重以及人机不同步,引起患者肺内炎症加重,氧合功能恶化,最终影响患者预后,增加病死率。本文就自主呼吸对重度ARDS患者呼吸功能的影响机制展开综述。  相似文献   
52.
Acute skin toxicity in adjuvant breast radiation can be reduced with modern radiotherapy (RT) techniques. However, having reviewed the literature, we found no dosimetric constraint for acute skin toxicity that would be applicable to modern RT planning. This study aimed to identify dosimetric factors that are associated with higher rates of acute skin toxicity. A retrospective review was carried out including women who received adjuvant forward-planned intensity-modulated radiotherapy (IMRT) after breast-conserving surgery. Acute skin toxicity grade was prospectively recorded. A total of 131 patients were analyzed. On multivariate analysis, the V105%?>?30?cc (p?=?0.013) and the use of conventional fractionation (CF) (p?=?0.001) were statistically significant for acute skin toxicity. On literature review, current quantitative dosimetric parameters that have shown statistical significance include a V107%?>?3?cc in hypofractionation (HF), V107%?>?9?cc in CF, treated volume 110%?>?5.13%, and V107%?>?28.6%. There is little evidence on the predictive value of clinically applicable dosimetric factors in acute skin toxicity. Given the recent improvements in RT planning, we would consider a V107% or a V110% too high a dosimetric value to be useful for the majority of patients. We have shown that a V105% of greater than 30?cc is significantly associated with acute skin toxicity, controlling for other variables. We suggest that this is currently the most useful modifiable parameter available to reduce skin toxicity and is applicable to modern RT planning. We also suggest that consideration be given to hypofractionated schedules to further reduce acute skin toxicity.  相似文献   
53.

Background

Glucocorticoids play essential roles in the treatment of childhood acute lymphoblastic leukaemia (ALL); however, treatment with these agents can result in severe side-effects. This study, the first of its kind in a Saudi population, investigates associations of ABCB1 gene polymorphisms (pharmacodynamics and pharmacokinetic) with the development of toxicity and side effects (glucose abnormality, liver toxicity and infection) in a small population of Saudi children with ALL.

Methods

Three single nucleotide polymorphisms (SNPs) of the ABCB1 gene (rs 3213619 T129C, rs 2032582 G2677T and rs1045642 C3435T) were analysed in 70 Saudi children with ALL and 60 control subjects. Participants were treated according to the ALL 2000 study protocol. Toxicities were assessed and associations with genotypes were evaluated according to Common Toxicity Criteria (NCI-CTC).

Results

Significant associations were observed among carriers and the mutated genotype C3435T (ABCB1), which had an incidence of infection (p?=?0.05). Although no correlations were found between liver toxicity and glucose abnormalities for patients carrying ABCB1 SNPs, risk factors for liver toxicity were elevated by a factor of three for patients carrying the SNP G2677T, OR 3.00 (1.034–8.702). The risk factor of glucose abnormality toxicity for the patients carring T129C were increased three times OR 3.06 (0.486–19.198).

Conclusions

In terms of infection incidence, polymorphism C3435T may contribute to potential life-threatening infections during paediatric ALL therapy, through glucocorticoid usage.  相似文献   
54.

Objective

Acute mesenteric ischemia (AMI) is an emergent event with a high mortality rate; survivors have high rates of intestinal failure. Restoration of blood flow using endovascular or surgical revascularization is associated with better outcome in terms of survival rate and intestinal resection. Retrograde open mesenteric stenting (ROMS), which is a hybrid technique, combines two benefits: prompt blood flow restoration with an endovascular approach and inspection and resection of the small bowel. The aim of the study was to assess the results of ROMS in thrombotic AMI in a retrospective multicenter study.

Methods

We retrospectively enrolled all consecutive patients who underwent ROMS revascularization for occlusive thrombotic AMI in three participating tertiary care centers between November 2012 and March 2017.

Results

Twenty-five patients (14 men and 11 women; mean age, 64.9 ± 11.6 years) were included. In two patients, ROMS was not possible because of failure of re-entry in the aortic lumen (technical success, 92%). One patient required revascularization of two visceral arteries and underwent an aortohepatic bypass. Five patients (20%) underwent endarterectomy and patch angioplasty of the superior mesenteric artery before retrograde stenting. Thirteen patients (52%) required bowel or colon resection (11 patients required both resections) during the initial procedure with a mean length of small bowel resection of 52 ± 87 cm. The 30-day operative mortality rate was 25%, and the overall 1-year survival rate was 65%. The 1-year primary patency rate was 92%. In one patient, postoperative imaging at 1 month showed stent migration in the aortic bifurcation.

Conclusions

ROMS for thrombotic AMI has a high technical success rate and a high midterm primary patency rate. It could be an alternative procedure to retrograde superior mesenteric artery bypass for patients when percutaneous endovascular revascularization is not indicated or has failed.  相似文献   
55.
Objective: To investigate the changes in serum miR-124 levels in patients with acute cerebral infarction (ACI) and elucidate the underlying mechanism by a dynamic monitor.

Methods: Fifty-four patients with ACI and 51 healthy controls were included in our study. Baseline characteristics and blood samples were collected for further analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the serum miR-124 levels. The dual-luciferase reporter assay was used to evaluate the effect of miR-124 on iASPP, a protein that inhibits apoptosis stimulating proteins in the p53 family.

Results: Compared with normal controls, the miR-124 levels in the ACI group rapidly decreased at phase 1 (within 24?h after ischemia) (p?<?0.001) and then gradually increased at phase 2 (48?~?72?h after ischemia) (p?<?0.001) and phase 3 (the 7th day after ischemia) (p?<?0.001). The dual-luciferase reporter assay showed that miR-124 down-regulates iASPP expression in 293T cells.

Conclusion: The miR-124 levels are down-regulated in ACI patients. The dynamic changes of miR-124 might provide a possible method for the detection of ischemic stroke.

  • Highlights
  • The difference in miR-124 expression levels between ACI patients and normal controls.

  • Dynamic changes of miR-124 expression levels in ACI patients.

  • The down-regulation of miR-124 upon iASPP expression.

  相似文献   
56.
BackgroundThe relationship between body mass index (BMI) and in-hospital mortality risk among patients with acute myocardial infarction (AMI) remains controversial.Methods and ResultsWe included 35,964 patients diagnosed with AMI in China Acute Myocardial Infarction registry between January 2013 and December 2016. Patients were categorized into 4 groups according to BMI level: BMI <18.5, 18.5–24.9, 25–30, and ≥30 kg/m2 for underweight, normal, overweight, and obese groups, respectively. Clinical data were extracted for each patient, and multivariable logistic regression analysis was used to examine the association between BMI level and in-hospital mortality. Compared with normal-weight patients, obese patients were younger, more often current smokers, and more likely to have hypertension, hyperlipidemia, and diabetes. Multivariable regression analysis results demonstrated that compared with normal group, underweight group had significantly higher in-hospital mortality (odds ratio [OR]: 1.34; 95% confidence interval [CI]: 1.06–1.69; p = 0.016), while overweight group (OR: 0.86; 95% CI: 0.77–0.97; p = 0.011) and obese group (OR: 0.65; 95% CI: 0.46–0.91; p = 0.013) had lower mortality. All subgroups showed a trend toward lower in-hospital mortality risk as BMI increased.ConclusionsOur study provided robust evidence supporting “obesity paradox” in a contemporary large-scale cohort of patients with AMI and demonstrated that increased BMI was independently associated with lower in-hospital mortality.  相似文献   
57.
58.
Background:Arsenic trioxide (ATO) is widely applied to treat acute promyelocytic leukemia (APL). To elucidate metabolism and toxicity of arsenic, we analyzed time course of arsenic species in red blood cells (RBCs) of APL patients.

Methods:Nine APL patients received ATO (0.16 mg/kg/day) through 18-h infusion. Blood was collected before daily administration (days 2 to 9), and at different time points on day 8. Inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were detected by HPLC-ICP-MS.

Results:Arsenic species reached Cmax at 18 h on day 8. Arsenicals gradually accumulated during days 2 to 9, whereas their percentages remained almost constant. The general trend in red blood cells (RBCs) was iAs > MMA > DMA. MMA was consistently the predominant methylated arsenic metabolite in RBCs. iAs, MMA, and tAs (tAs = iAs + DMA + MMA) concentrations (P < 0.0001), MMA/DMA ratios (P = 0.0016) and iAs% (P = 0.0013) were higher in RBCs than in plasma.

Conclusions:Time course of arsenic species reveal kinetic characteristic of ATO metabolites in RBCs. Arsenic species accumulated with administration frequency. Arsenic species in RBCs were remarkably different from those in plasma. Time course of arsenic species in RBCs is important in ATO clinical application.  相似文献   

59.
Kawasaki disease (KD) is a systemic vasculitis frequent in children younger than 5 years of age. It involves coronary arteries and other medium-sized vessels. There also exists evidence of inflammatory and proliferative changes affecting the biliary tract and lymphocyte infiltration of the renal interstitial. We describe the case of a 9-year-old girl who developed high-grade fever, bilateral non-purulent conjunctivitis, «strawberry» tongue, desquamation of the fingers and toes, cholestatic syndrome, edema and elevated serum creatinine. KD is a diagnostic challenge for the pediatrician. In every patient with high-grade fever, cholestasis and acute kidney injury, KD should be included in the differential diagnosis, even though more research is necessary to evaluate this atypical association.  相似文献   
60.

Study objectives

The primary objective of this study was to compare Emergency Department patients with first-time versus recurrent acute pancreatitis.

Methods

This study was a retrospective chart review of patients with a diagnosis of acute pancreatitis who presented to a single academic urban emergency department from 2012 to 2016. Criteria for inclusion were clinical symptoms of pancreatitis, age greater than or equal to 18?years, ED diagnosis of acute pancreatitis, and an abdominal CT scan within 24?h of triage. Exclusion criteria were traumatic mechanism and pregnancy. Charts were reviewed by a minimum of two trained abstractors using structured data collection sheets and discrepancies were resolved by a third abstractor. Patients with first time acute pancreatitis versus recurrent acute pancreatitis were compared to determine differences in characteristics, management and disposition.

Results

250 patients were included in the study. Of these, 165 patients had first-time acute pancreatitis and 85 patients had recurrent acute pancreatitis. Demographics, vital signs and initial lab values were the same in both groups. Patients with recurrent acute pancreatitis were more likely to have significant findings on CT (Modified CT Severity Index, 2.09 versus 1.43, p?<?0.05), more likely to require IV opiates (96% versus 75%, p?<?0.001) and less likely to need ICU admission (8% versus 19%, p?=?0.03).

Conclusion

ED patients with recurrent acute pancreatitis demonstrated more significant findings on CT compared to patients with first-time acute pancreatitis but were less likely to require ICU admission.  相似文献   
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