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1.

Background

Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to median sternotomy (MS) for multiple valvular disease (MVD). This systematic review and meta-analysis aims to compare operative and peri-operative outcomes of MIS vs MS in MVD.

Methods

PubMed, Ovid, and Embase were searched from inception until August 2019 for randomized and observational studies comparing MIS and MS in patients with MVD. Clinical outcomes of intra- and postoperative times, reoperation for bleeding and surgical site infection were evaluated.

Results

Five observational studies comparing 340 MIS vs 414 MS patients were eligible for qualitative and quantitative review. The quality of evidence assessed using the Newcastle-Ottawa scale was good for all included studies. Meta-analysis demonstrated increased cardiopulmonary bypass time for MIS patients (weighted mean difference [WMD], 0.487; 95% confidence interval [CI], 0.365-0.608; P < .0001). Similarly, aortic cross-clamp time was longer in patients undergoing MIS (WMD, 0.632; 95% CI, 0.509-0.755; P < .0001). No differences were found in operative mortality, reoperation for bleeding, surgical site infection, or hospital stay.

Conclusions

MIS for MVD have similar short-term outcomes compared to MS. This adds value to the use of minimally invasive methods for multivalvular surgery, despite conferring longer operative times. However, the paucity in literature and learning curve associated with MIS warrants further evidence, ideally randomized control trials, to support these findings.
  相似文献   
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Bronchiolitis obliterans (BO) is a survival-limiting factor in lung transplantation. There are no common BO markers in use. Since BO is associated with extracellular matrix remodeling, we asked whether matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs) could serve as BO markers. In 72 lung transplant patients (34 BO syndrome (BOS) 0, 15 BOS 0-p, and 23 BOS 1) serum and broncho-alveolar lavage (BAL) MMP and TIMP levels were examined by ELISA. The BAL cell counts were additionally analyzed. The serum MMP-2, MMP-8, MMP-9 and TIMP-2 levels were not different in all groups. In contrast, the BAL MMP-8, -9 and TIMP-1 levels were significantly elevated in BOS 0-p (p = 0.003; p = 0.007; p = 0.0003, respectively) and BOS 1 (p = 0.003; p = 0.001; p = 0.0004, respectively) as compared to BOS 0 patients. The BAL MMP-8, -9 and TIMP-1 levels were significant predictors of BOS 0-p (p = 0.01; p = 0.01; p = 0.01, respectively) and BOS-1 (p = 0.007; p = 0.01; p = 0.006, respectively) in receiver operating characteristic analysis. Except for BAL macrophages that were significantly decreased in BOS 0-p versus BOS 0 patients; other cell counts were not different between the groups. BAL MMP-8, -9 and TIMP-1 might be useful markers to detect BO in lung transplant patients.  相似文献   
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Taban-Arshan extract decreased expression of T-lymphocyte activation markers, normalized T-cell-mediated immunity, and suppressed increased activity of natural killer receptors during culturing with lymphocytes of patients with atopic bronchial asthma. Taban-Arshan extract normalized activation processes in the B-cell immunity and stimulated expression of receptors of activation-induced apoptosis. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 7, pp. 76–78, July, 2004  相似文献   
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BackgroundThe NCCN guidelines recommend active surveillance (AS) as an option for the initial management of cT1a 0-2 cm renal lesions. However, data about comparison between renal cell carcinoma (RCC) 0-2 cm vs. 2.1-4 cm are scarce.MethodsWithin the Surveillance, Epidemiology, and End Results database (2002–2016), 46,630 T1a NanyMany stage patients treated with nephrectomy were identified. Data were tabulated according to histological subtype, tumor grade (low [LG] vs. high [HG]), as well as age category and gender. Additionally, rates of synchronous metastases were quantified.ResultsOverall, 69.3 vs. 74.1% clear cell, 21.4 vs. 17.6% papillary, 6.9 vs. 6.8% chromophobe, 2.0 vs. 1.1% sarcomatoid dedifferentiation, 0.2 vs. 0.2% collecting duct histological subtype were identified for respectively 0-2 cm and 2.1-4 cm RCCs. In both groups, advanced age was associated with higher rate of HG clear cell and HG papillary histological subtype. In 0-2 cm vs. 2.1-4 cm RCCs, 13.8% vs. 20.2% individuals operated on harbored HG tumors and were more prevalent in males. Lower synchronous metastases rates were recorded in 0-2 cm RCC and ranged from 0 in respectively multilocular cystic to 0.9% in HG papillary histological subtype. The highest synchronous metastases rates were recorded in sarcomatoid dedifferentiation histological subtype (13.8% and 9.7%) in both groups.ConclusionsRelative to 2.1-4 cm RCCs, 0-2 cm RCCs harbored lower rates of HG tumors, lower rates of aggressive variant histology and lower rates of synchronous metastases. The indications and demographics of patients selected for AS may be expanded in the future to include younger and healthier patients.  相似文献   
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There is a well‐documented shortage of physician researchers, and numerous training programs have been launched to facilitate development of new physician scientists. Short‐term research training programs are the most practical form of research exposure for most medical students, and the summer between their first and second years of medical school is generally the longest period they can devote solely to research. The goal of short‐term training programs is to whet the students’ appetite for research and spark their interest in the field. Relatively little research has been done to test the effectiveness of short‐term research training programs. In an effort to examine short‐term effects of three different NIH‐funded summer research training programs for medical students, we assessed the trainees’ (N = 75) research self‐efficacy prior to and after the programs using an 11‐item scale. These hands‐on training programs combined experiential, didactic, and mentoring elements. The students demonstrated a significant increase in their self‐efficacy for research. Trainees’ gender, ranking of their school, type of research, and specific content of research project did not predict improvement. Effect sizes for different types of items on the scale varied, with the largest gain seen in research methodology and communication of study findings.  相似文献   
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