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1.
The aim of this study was to analyze the dynamic changes of QT interval--heart rate relation during exercise, fitting their reciprocal variations to an exponential formula (QT = A - B.exp(-k.RR], in order to see whether diagnostic contributions might so be derived. The authors studied 139 patients who underwent a simultaneous assessment of regional myocardial perfusion and ventricular function by means of two injections of 99mTc-methoxy-isobutyl-isonitrile at rest and at peak of a submaximal exercise test, using first pass radionuclide angiography with multielement gamma-camera and single photon emission computerized tomography, in order to detect and localize the presence of stress-induced myocardial ischemia. According to radionuclide results, patients were divided into three groups: group A, 7 individuals with no sign of stress-induced myocardial ischemia; group B, 79 patients with evidence of ischemia in 1 (16.5%), 2 (65.5%), or 3 (17.7%) main coronary territories; and group C, 53 patients with previous infarction and evidence of ischemia in other territories. Conventional analysis of the exercise test (greater than or equal to 0.1 mV ST depression) showed a pathological response in no individual of group A, in 34 patients of group B (43%), and in 27 patients of group C (50.9%); overall sensitivity was 46.2%, specificity 100%, and diagnostic accuracy 48.9%. Exponential coefficients A, B, and k showed wide overlap of values among the three groups, although a significant difference was present in mean k values between groups A and B (p less than 0.001), and group C (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Differing contexts have greatly influenced HTA development in various countries, with considerable effort recently made by international HTA networks (e.g., EUnetHTA) and the European Union (EU) to make HTA a more coherent, equal, and efficient process. Medical devices (MDs) present particular challenges for HTA because of frequent, rapid innovation, outcomes influenced by end-user competence, dynamic pricing and often low-quality scientific evidence. Our objective is to describe the development, structure and governance of a National HTA Program for MDs (PNHTADM) in Italy, a highly participatory, stakeholder-engaged, evidence-based process to reform a fragmented system of appraisal and approval. Based largely on EUnetHTA methods, the resulting process delineates a standardized system for proposing MDs by any stakeholders, accrediting HTA producers, setting criteria for prioritization and appraisals, and innovatively linking recommendations with coverage, reimbursement and procurement of MDs. Expected benefits include reduced disparities in pricing and reimbursement policies and improved access to new technologies across 21 regional healthcare systems in Italy's decentralized, universal system, complete with provisions to require additional evidence collection and centrally monitor diffusion. Though devised for Italy, the design, resources and underlying analysis provide a framework for other nations seeking to consolidate HTA initiatives, particularly in light of new EU regulation.  相似文献   
3.
4.
AIM: To evaluate whether lymph node pick up by separate stations could be an indicator of patients submitted to appropriate surgical treatment. METHODS: One thousand two hundred and three consecutive gastric cancer patients submitted to radical resection in 7 general hospitals and for whom no information was available on the extension of lymphatic dissection were included in this retrospective study. RESULTS: Patients were divided into 2 groups: group A, where the stomach specimen was directly formalinfixed and sent to the pathologist, and group B, where lymph nodes were picked up after surgery and fixed for separate stations. Sixty-two point three percent of group A patients showed 16 retrieved lymph nodes compared to 19.4% of group B(P 0.0001). Group B(separate stations) patients had significantly higher survival rates than those in group A [46.1 mo(95%CI: 36.5-56.0) vs 27.7 mo(95%CI: 21.3-31.9); P = 0.0001], independently of T or N stage. In multivariate analysis, group A also showed a higher risk of death than group B(HR = 1.24; 95%CI: 1.05-1.46).CONCLUSION: Separate lymphatic station dissection increases the number of retrieved nodes, leads to better tumor staging, and permits verification of the surgical dissection. The number of dissected stations could potentially be used as an index to evaluate the quality of treatment received.  相似文献   
5.
Patients presenting for emergency abdominal procedures often have medical issues that cause both general anaesthesia and central neuraxial blockade to pose significant risks. Regional anaesthetic techniques are often used adjunctively for abdominal procedures under general anaesthesia, but there is limited published data on procedures done under peripheral nerve or plexus blocks. We herein report the case of a patient with recent pulmonary embolism and supraventricular tachycardia who required colostomy refashioning. Ultrasonography-guided regional anaesthesia was administered using a combination of ilioinguinal-iliohypogastric, rectus sheath and transversus abdominis plane blocks. This was supplemented with propofol and dexmedetomidine sedation as well as intermittent fentanyl and ketamine boluses to cover for visceral stimulation. We discuss the anatomical rationale for the choice of blocks and compare the anaesthetic conduct with similar cases that were previously reported.  相似文献   
6.
7.
Age-related differences in wound healing have been documented but little is known about the wound healing mechanism after burns. Our aim was to compare histological features and immunohistochemical expression of matrix metalloproteinase-9 (MMP-9), collagen IV, K6 and CD44 in the burn wound healing process in aged and young rats.  相似文献   
8.
Enhancing the quantity and quality of cancellous bone with anabolic pharmacologic agents may lead to more successful outcomes of non-cemented joint replacements. Using a novel rabbit model of cancellous bone loading, we examined two specific questions regarding bone formation at the bone–implant interface: (1) does the administration of intermittent PTH, a potent anabolic agent, and mechanical loading individually and combined enhance the peri-implant cancellous bone volume fraction; and, (2) does surgical trauma enhance the anabolic effect of PTH on peri-implant bone volume fraction. In this model, PTH enhanced peri-implant bone volume fraction by 30% in loaded bone, while mechanical loading alone increased bone volume fraction modestly (+ 10%). Combined mechanical loading and PTH treatment had no synergistic effect on any cancellous parameters. However, a strong combined effect was found in bone volume fraction with combined surgery and PTH treatment (+ 34%) compared to intact control limbs. Adaptive changes in the cancellous bone tissue included increased ultimate stress and enhanced remodeling activity. The number of proliferative osteoblasts increased as did their expression of pro-collagen 1 and PTH receptor 1, and the number of TRAP positive osteoclasts also increased. In summary, both loading and intermittent PTH treatment enhanced peri-implant bone volume, and surgery and PTH treatment had a strong combined effect. This finding is of clinical importance since enhancing early osseointegration in the post-surgical period has numerous potential benefits.  相似文献   
9.

Purpose

Intracoronary bleaching is a minimally invasive, alternative treatment that addresses aesthetic concerns related to non-vital teeth discoloration. However, to the best of our knowledge, no studies have assessed the psychosocial impacts of such procedures on patients’ aesthetic perceptions. The aim of this study was to evaluate aesthetic perceptions and the psychosocial impact of patients up to 3 months after their teeth had been bleached with hydrogen peroxide (35%) and carbamide peroxide (37%) using the walking bleach technique.

Methods

The patients were randomly divided into two groups according to the bleaching agent used: G1?=?hydrogen peroxide 35% (n?=?25) and G2?=?carbamide peroxide 37% (n?=?25). Non-vital bleaching was performed in four sessions. Color was objectively (ΔE) and subjectively (ΔSGU) evaluated. Aesthetic perception and psychosocial factors were evaluated before, 1 week and 1 month after the bleaching using the Oral Health Impact Profile (OHIP) and Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) questionnaires.

Results

The color change (ΔE) values at 1 month were G1?=?16.80?±?6.07 and G2?=?14.09?±?4.83. These values remained stable until the third month after treatment (p?>?0.05). There was a decrease in the values of OHIP-aesthetics and PIDAQ after treatment versus baseline (p?<?0.05). This status was maintained through the third month after treatment.

Conclusions

Both agents were highly effective and had a positive impact on the aesthetic perception and psychosocial impact of patients, values that also remained stable over time. Non-vital bleaching yields positive and stable impacts on aesthetic perception and psychosocial factors. ClinicalTrials.gov identifier NCT02718183.
  相似文献   
10.
Introduction

Studies focusing on enchondroma and atypical cartilaginous tumour (ACT) of the pelvis are lacking. The purpose of this study was to verify possible clinical and radiological findings with regard to distinguishing enchondromas from ACT of the pelvis. In addition, this study analysed functional and oncological outcomes in patients with enchondromas or ACT of the pelvis treated with curettage or resection.

Materials and methods

We retrospectively reviewed the medical records of 21 patients with confirmed enchondroma or ACT of the pelvis treated by curettage or resection from 1985 to 2018. The minimum follow-up was 18 months. The relationship between clinical and radiological factors and tumour type or local recurrence was assessed using Fisher exact test and Mann–Whitney U test.

Results

Endosteal scalloping (p = 0.039), tumour size (0.005) and age (0.006) were shown to statistically favour ACT over enchondroma; by contrast, enchondroma and ACT patients had no difference in pain frequency (p = 0.5528). All patients with enchondroma had no local recurrence; in contrast, local recurrence occurred in one patient with ACT, initially treated with resection. The patient with local recurrence had a disease progression with a higher histological grade than the original tumour. Patients treated with curettage had better functional outcomes than patients treated with resection (p = 0.001).

Discussion

Endosteal scalloping, tumour size and age could be helpful in the differential diagnosis between enchondroma and ACT of the pelvis. In addition, our study showed that ACT of the pelvis can be safely treated with curettage due to a low risk of local recurrence and better functional results compared with resection. In case of recurrence, we suggest to treat these patients with resection for the risk of disease progression.

  相似文献   
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