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71.
A 29-year-old man was admitted with high-grade fever, crampy abdominal pain, and watery diarrhea that had persisted for 2 weeks before his admission. Symptomatic treatment (acetaminophen only) was of no benefit. On physical examination, there was diffuse abdominal tenderness. Laboratory tests showed a leukomoid reaction with atypical lymphocytosis, and serology tests revealed acute cytomegalovirus infection. Abdominal computed tomography and colonoscopy revealed an inflammatory process involving the large intestine. On histologic examinations of intestinal biopsy samples, there was an active inflammation with no inclusion bodies.The patient was treated with ganciclovir with only mild improvement. Adding 5-aminosalicylic acid caused little further improvement. Repeated colonoscopy performed 2 months later showed severe chronic ulcerative colitis. Only the addition of systemic steroids caused complete resolution of the symptoms.On review of the literature (Medline search for cytomegalovirus colitis in immunocompetent patients), 18 cases were found. On follow-up, 10 of these patients were found to have inflammatory bowel disease.  相似文献   
72.
Objective: Investigation of the clinical potential of extensive phenotype data and machine learning (ML) in the prediction of mortality in acute coronary syndrome (ACS).Methods: The value of ML and extensive clinical data was analyzed in a retrospective registry study of 9066 consecutive ACS patients (January 2007 to October 2017). Main outcome was six-month mortality. Prediction models were developed using two ML methods, logistic regression and extreme gradient boosting (xgboost). The models were fitted in training set of patients treated in 2007–2014 and 2017 (81%, n = 7344) and validated in a separate validation set of patients treated in 2015–2016 with full GRACE score data available for comparison of model accuracy (19%, n = 1722).Results: Overall, six-month mortality was 7.3% (n = 660). Several variables were found to be significantly associated with six-month mortality by both ML methods. The xgboost scored the best performance: AUC 0.890 (0.864–0.916). The AUC values for logistic regression and GRACE score were 0.867(0.837–0.897) and 0.822 (0.785–0.859), respectively. The AUC value of xgboost was better when compared to logistic regression (p = .012) and GRACE score (p < .00001).Conclusions: The use of extensive phenotype data and novel machine learning improves prediction of mortality in ACS over traditional GRACE score.

KEY MESSAGES

  • The collection of extensive cardiovascular phenotype data from electronic health records as well as from data recorded by physicians can be used highly effectively in prediction of mortality after acute coronary syndrome.
  • Supervised machine learning methods such as logistic regression and extreme gradient boosting using extensive phenotype data significantly outperform conventional risk assessment by the current golden standard GRACE score.
  • Integration of electronic health records and the use of supervised machine learning methods can be easily applied in a single centre level to model the risk of mortality.
  相似文献   
73.
The causes of many sporadic diseases are unexplained; the contribution of recessive loci with reduced penetrance is one possibility that has been difficult to explore. We describe an approach to this problem by first searching for diseases with higher prevalence in populations with high rates of consanguinity, then determining whether disease cases are more commonly the product of consanguinous union than controls in such populations, followed by analysis of genetic linkage in consanguinous cases. We demonstrate the utility of this approach by investigation of congenital heart disease in Iran. We found that patent ductus arteriosus (PDA), a common congenital heart disease, accounts for a higher fraction of congenital heart disease in Iran (15%) than in the United States (2-7%). Moreover, Iranian PDA cases demonstrated a marked increase of parental consanguinity (63%), compared with the general Iranian population (25%) or control cases with tetralogy of Fallot (30%). The recurrence of PDA among siblings was 5%. A genomewide analysis of linkage in 21 unrelated consanguinous PDA cases demonstrated a multipoint logarithm of odds score of 6.27 in favor of linkage of PDA to a 3-centimorgan interval of chromosome 12q24, with 53% of kindreds linked. These findings together establish a recessive component to PDA and implicate a single locus, PDA1, in one third or more of all PDA cases in Iran; they further suggest a role for this locus in PDA worldwide. Finally, these results suggest a general approach to the identification of recessive contributions to sporadic diseases.  相似文献   
74.
ObjectivesIntravenous therapy is a complex procedure usually requiring the preparation of the medication in the clinical area before administration to the patient. Breaches in aseptic technique may result in microbial contaminations of vials which is a potential cause of different avoidable infections. We aimed to investigate the prevalence and pattern of microbial contamination of single- and multiple-dose vials in the largest pulmonary teaching hospital in Iran.MethodsIn a period of 2 months, opened single- and multiple-dose vials from different wards were sampled by a pharmacist. The name of the medication, ward, labeling of the vials, the date of opening, and storing temperature were recorded for each vial. Remained contents of each vial were cultured using appropriate bacterial and fungal growth media.ResultsMicrobial contamination was identified in 11 of 205 (5.36%) of vials. The highest contamination rate was 14.28% for vials used in interventional bronchoscopy unit. The most frequent contaminated medication was insulin. Gram-positive bacteria (81.82%) were more significantly involved than gram-negative ones (9.09%) and fungi (9.09%), with the highest frequency for Staphylococcus epidermidis.ConclusionsOur data demonstrate that repeated use of vials especially if basic sterility measures are disobeyed can cause microbial contamination of administered products to the patients. Infection preventionists are responsible to train health care workers regarding aseptic techniques and apply guidelines for aseptic handling of intravenous solutions.  相似文献   
75.
76.
IntroductionHigh smoking prevalence leads to increased morbidity and mortality in individuals with depression/anxiety. Integrated interventions targeting both smoking and mood have been found to be more effective than those targeting smoking alone, but the mechanisms of change of these interventions have not been investigated. This qualitative study aimed to understand participants'' experiences of the mechanisms underlying change in smoking behaviour following an integrated cognitive behavioural technique‐based intervention for smoking cessation and depression/anxiety.MethodsThis study was embedded within an ongoing randomized‐controlled acceptability and feasibility trial (http://www.isrctn.com/ISRCTN99531779). Semistructured interviews were conducted with 15 IAPT service users. Data were analysed using thematic analysis. During the interviews, participants were asked open‐ended questions about their quitting experience and perception of how the intervention aided their behaviour change.ResultsFive themes were identified. Acquiring an increased awareness of smoking patterns: participants described an increased understanding of how smoking was contributing towards their mental health difficulty. Developing individualized strategies: participants described acquiring ‘a couple of tricks up your sleeve’ that were helpful in making smoking cessation feel more ‘manageable’. Practitioner style as ‘supportive but not lecture‐y’: participants expressed how important the therapeutic alliance was in helping change their smoking behaviour. Importance of regular sessions: participants expressed the importance of ‘having someone that''s checking in on you’. Having the opportunity to access the intervention at ‘the right time’: participants described the intervention as the ‘push’ that they ‘needed’.ConclusionsParticipants identified key factors towards smoking behaviour change. Perceived increased awareness of how smoking negatively impacted participants'' mental health, and the opportunity to be offered smoking cessation treatment in a ‘non‐judgemental’, ‘supportive’ environment, with regular sessions and individualized strategies contributed to successful smoking cessation outcomes. If similar results are found in more diverse samples, these aspects should be embedded within integrated interventions for smoking cessation and depression/anxiety.Patient or Public ContributionPersons with lived experience of depression, anxiety and tobacco addiction contributed towards the design of the interview schedule, participant information sheets and the debriefing process. This was to ensure that interview questions were relevant, nonjudgemental and acceptable for those who did not manage to quit smoking.  相似文献   
77.
Abstract

Purpose: Initial studies of combinations of radioiodine therapy (RIT) and local ablative procedures for the treatment of thyroid nodules have shown promising results. The goal of this study was to evaluate the effectiveness of RIT combined with radiofrequency ablation (RFA) in patients with goitres and to determine which ablative procedure is the most suitable for a combined therapy.

Methods: Thirty patients with goitres were divided into two subgroups. A test group of 15 patients received combined therapy (RIT?+?RFA) and a control group of 15 patients received RIT mono therapy. All patients underwent assessments including ultrasound, laboratory evaluation (T3, T4, TSH, TG, TPOAb, TgAbTRAb) and scintigraphic imaging with Tc-99m-Pertechnetate. The 3-month volume reduction was used to evaluate therapy effectiveness.

Results: Combined therapy (subgroup 1) resulted in a significant (p?<?0.05) thyroid volume reduction (22.3?±?54?ml/32.2?±?58.2%) with better performance (p?>?0.05) than the control group (20.2?±?32.2?ml/29.6?±?42.1%). All patients became euthyroid after treatment. No major discomfort or complications occurred. A review of the literature investigating combinations of other local ablative procedures with RIT was performed to determine the most promising combination.

Conclusions: The present study confirms the positive experiences with the combined therapy of RIT and local ablative procedures shown in the current literature and approves this approach for the treatment of goitres with RFA?+?RIT. These findings, when confirmed by further studies, should expand the indication of combined therapy as a minimally invasive alternative to surgery.  相似文献   
78.
Microscopic magnetic resonance elastography (microMRE).   总被引:2,自引:0,他引:2  
Magnetic resonance elastography (MRE) was extended to the microscopic scale to image low-frequency acoustic shear waves (typically less than 1 kHz) in soft gels and soft biological tissues with high spatial resolution (34 micromx34 micromx500 microm). Microscopic MRE (microMRE) was applied to agarose gel phantoms, frog oocytes, and tissue-engineered adipogenic and osteogenic constructs. Analysis of the low-amplitude shear wave pattern in the samples allowed the material stiffness and viscous loss properties (complex shear stiffness) to be identified with high spatial resolution. microMRE experiments were conducted at 11.74 T in a 56-mm vertical bore magnet with a 10 mm diameterx75 mm length cylindrical space available for the elastography imaging system. The acoustic signals were generated at 550-585 Hz using a piezoelectric transducer and high capacitive loading amplifier. Shear wave motion was applied in synchrony with the MR pulse sequence. The field of view (FOV) ranged from 4 to 14 mm for a typical slice thickness of 0.5 mm. Increasing the agarose gel concentration resulted in an increase in shear elasticity and shear viscosity. Shear wave motion propagated through the frog oocyte nucleus, enabling the measurement of its shear stiffness, and in vitro shear wave images displayed contrast between adipogenic and osteogenic tissue-engineered constructs. Further development of microMRE should enable its use in characterizing stiffer materials (e.g., polymers, composites, articular cartilage) and assessing with high resolution the mechanical properties of developing tissues.  相似文献   
79.
The reactivity of primary and secondary hydroxyl groups of cellulose towards chlorotri(p-tolyl)methane in pyridine was studied in the temperature range of 60 to 100°C. The rate of reaction with the primary hydroxyl groups was found to be 43 times faster than that with the secondary hydroxyl groups of cellulose. The kinetic data showed that the reactivity of chlorotri(p-tolyl)methane towards primary hydroxyl groups of cellulose is higher than that of chlorotriphenylmethane (trityl chloride). The energies of activation for the reaction of primary and secondary hydroxyl groups of cellulose with chlorotri(p-tolyl)methane were found to be 39,6 and 43,1 kJ · mol?1, respectively. The reaction was observed to be pseudo first order.  相似文献   
80.
Carotid stenting has recently been considered as an alternative treatment to carotid endarterectomy for certain patients with carotid stenosis. Hence, performing carotid arteriography with minimal morbidity and mortality is essential. The purpose of this study was to audit complications of diagnostic carotid/cerebral arteriography performed by a vascular surgeon with experience in endovascular interventions. One hundred one consecutive patients underwent 4-vessel arch aortography with selective carotid, subclavian, and/or vertebral arteriography with use of the Seldinger technique. Demographic data, indications, procedure approach (transfemoral, brachial), number of arteries punctured, type of selective injection, contrast volume, and procedure time were analyzed. Minor complications were those that do not significantly alter the health or activity of the patient or require extra hospitalization or treatment. Other complications were defined as major complications. The technical success rate was 99% (100/101 patients). These included the following: 82 patients with right carotid artery, 82 with left carotid artery, 15 with right subclavian artery, 21 with left subclavian artery, 11 with right vertebral artery, and 17 with left vertebral artery (a total of 228 selective injections). Indications for procedures included the following: transient ischemic attack (TIA)/stroke symptoms in 66%, asymptomatic carotid stenosis in 22%, upper limb claudication in 4%, and vertebrobasilar insufficiency in 4%. Right femoral puncture was used in 79%, left femoral in 12%, and left brachial in 9%. The mean amount of contrast used was 101 cc (45-250 cc) and the mean procedure time was 46 minutes (22-132 minutes). There were 5 complications in the whole series: 3 major complications (3%), including 1 minor stroke (1%) with carotid injection, 1 TIA, and 1 major retroperitoneal bleeding; and 2 (2%) minor complications. The major complication rate in this series compares favorably to published rates of 5.7% to 9.1%. There was no association between complications and specific risk factors except for a longer catheterization time (66 minutes versus 45 minutes, p=0.011). Carotid/cerebral arteriography can be done safely by experienced vascular surgeons with minimal perioperative complications that compare favorably with what has been reported in the radiology literature.  相似文献   
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