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81.
BACKGROUND: Advances in multidetector computed tomography (MDCT) technology now permit three-dimensional cardiac imaging with high spatial and temporal resolution. Historically, transesophageal echocardiography (TEE) has been the gold standard for assessment of the left atrial appendage (LAA) in patients with atrial fibrillation and other atrial arrhythmias. Findings on TEE, including demonstration of LAA thrombus and dense nonclearing spontaneous echocardiographic contrast (SEC), predict future fatal and nonfatal thromboembolic events. OBJECTIVE: The purpose of this study was to compare the diagnostic performance of 64-detector row MDCT in detecting LAA thrombus and dense nonclearing SEC as identified by TEE in patients undergoing pulmonary vein isolation for treatment of atrial fibrillation. METHODS: A total of 72 consecutive patients (69.4% male; mean age 56.1 +/- 10.3 years) underwent both MDCT and TEE for evaluation of the LAA (median intertest interval 0 days, interquartile range 0-5 days). MDCT assessment of the LAA was performed by two methods: (1) comparison of Hounsfield unit (HU) densities in the LAA apex to the ascending aorta (AscAo) in the same axial plane and (2) nonquantitative visual identification of a filling defect in the LAA. TEE evaluation of the LAA included identification of echodense intracavitary masses in the LAA as well as pulsed-wave Doppler interrogation of the LAA ostium. RESULTS: Patients with LAA thrombus or dense nonclearing SEC by TEE exhibited significantly lower LAA/AscAo HU ratios than patients who did not (0.82 +/- 0.22 vs 0.39 +/- 0.19, P <.001). LAA/AscAo HU cutoff ratios < or = 0.75 correlated to LAA thrombus or dense nonclearing SEC by TEE, with 100% sensitivity, 72.2% specificity, 28.6% positive predictive value, and 100% negative predictive value. HU ratios < or = 0.75 were associated with pulsed-wave Doppler velocities <50 cm/s of the LAA ostium (P <.001). In multivariable analysis, LAA/AscAo HU ratio < or = 0.75 remained a robust predictor of LAA thrombus or dense nonclearing SEC by TEE (P <.001). In contrast, MDCT identification of TEE-identified LAA thrombus or dense nonclearing SEC by visual detection of LAA filling defects resulted in lower sensitivity (50%) and negative predictive value (95.1%). CONCLUSION: Current-generation MDCT successfully identifies LAA thrombus and dense nonclearing SEC with high sensitivity and moderate specificity. Importantly, LAA/AscAo HU ratios >0.75 demonstrate 100% negative predictive value for exclusion of LAA thrombus or dense nonclearing SEC. These results suggest that in patients undergoing pulmonary vein isolation procedures, MDCT examinations that demonstrate LAA/AscAo HU ratios >0.75 may preclude the need for preprocedural TEE.  相似文献   
82.
Hui CK  Lie A  Au WY  Leung YH  Ma SY  Cheung WW  Zhang HY  Chim CS  Kwong YL  Liang R  Lau GK 《Blood》2005,106(2):464-469
The long-term hepatic complications after allogeneic hematopoietic stem cell transplantation (HSCT) in hepatitis B virus (HBV) endemic area are unknown. We examined the serological and liver-related outcome of 803 consecutive patients who received allogeneic HSCTs, with a median follow-up period of 83 months (range, 0.5-155 months). Late HBV-related hepatitis occurred in 2 of the 721 hepatitis B surface antigen-negative (HBsAg-) recipients compared with 16 of the 82 HBsAg+ recipients after HSCT (0.3% vs 19.5%; P < .001 by log-rank). Liver cirrhosis developed in 8 of the 82 HBsAg+ recipients compared with none of the 721 HBsAg- recipients (9.8% vs 0%; P < .001 by log-rank). Twenty of the 31 (64.5%) HBsAg+ recipients of hematopoietic stem cells from donors with natural immunity to HBV had sustained serologic clearance of HBsAg after HSCT. Eight of the 62 recipients without sustained HBsAg clearance compared with none of the 20 recipients with sustained HBsAg clearance developed liver cirrhosis (12.9% vs 0%; P = .02 by log-rank). Our study showed that long-term hepatic complications occur in a significant proportion of HBsAg+ patients after HSCT and the incidence of liver cirrhosis is reduced in those with sustained serologic clearance of HBsAg after HSCT.  相似文献   
83.
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.  相似文献   
84.
85.

Introduction

Traumatic tendon lacerations are a common problem encountered by hand surgeons worldwide. Although the use of barbed suture to repair tendon lacerations has gained theoretical popularity in recent years, there is little information available regarding the safety, efficacy, longevity, or complications encountered when used in tenorraphy. In this study, we review the available literature on the use of barbed suture in tendon repair.

Methods

Studies conducted between 1980 and 2014 were identified using several databases, including EMBASE, SCOPUS, MEDLINE, and Web of Science. Keywords used to search for appropriate studies included the following: barbed, v loc, quill, tendon, tendon injuries, suture, tenorraphy, injury, and laceration, in various combinations.

Results

Our initial literature search identified 47 articles, and 8 were deemed appropriate for review after applying our exclusion criteria. The data from each of the articles is reviewed for the following major categories:
  1. Maximum load to failure
  2. Mode of failure
  3. Load to 2-mm gap
  4. Change in cross-sectional area
  5. Type of repair

Conclusions

Barbed suture tenorraphy has a myriad of theoretical advantages, supported by varying ex vivo studies, as compared to traditional techniques. However, due to the non-uniformity in current studies and the lack of available data in a live model, we are unable to argue for or against barbed suture tenorraphy. We believe our review provides the most in-depth analysis of barbed suture tenorraphy to date, illuminates the potential advantages of using barbed sutures, and highlights the need for further investigation into this technique.  相似文献   
86.
Tolerogenic dendritic cells (DCs) play a critical role in the induction of regulatory T cells (Tregs), which in turn suppress effector T cell responses. We have previously shown the induction of DCs from human and mouse monocytic cell lines, mouse splenocytes and human peripheral blood monocytes by a novel apolipoprotein E (ApoE)‐derived self‐peptide termed Ep1.B. We also showed that this C‐terminal region 239–252 peptide of ApoE has strong anti‐atherogenic activity and reduces neointimal hyperplasia after vascular surgery in rats and wild‐type as well as ApoE‐deficient mice. In this study, we explored the phenotype of DC subset induced by Ep1.B from monocytic cell lines and from the bone marrow‐derived cells. We found Ep1.B treatment induced cells that showed characteristics of plasmacytoid dendritic cells (pDC). We explored in‐vitro and in‐vivo effects of Ep1.B‐induced DCs on antigen‐specific T cell responses. Upon in‐vivo injection of these cells with antigen, the subsequent ex‐vivo antigen‐specific proliferation of lymph node cells and splenocytes from recipient mice was greatly reduced. Our results suggest that Ep1.B‐induced pDCs promote the generation of Treg cells, and these cells contribute to the induction of peripheral tolerance in adaptive immunity and potentially contribute its anti‐atherogenic activity.  相似文献   
87.
Although initial rituximab‐containing chemotherapies achieve high response rates, indolent B‐cell non‐Hodgkin lymphoma (B‐NHL), such as follicular lymphoma (FL), is still incurable. Therefore, new effective agents with novel mechanisms are anticipated. In this multicentre phase II study, patients with relapsed/refractory indolent B‐NHL and mantle cell lymphoma (MCL) received vorinostat 200 mg twice daily for 14 consecutive days in a 21‐d cycle until disease progression or unacceptable toxicity occurred. The primary endpoint was overall response rate (ORR) in FL patients and safety and tolerability in all patients. Secondary endpoints included progression‐free survival (PFS). Fifty‐six eligible patients were enrolled; 50 patients (39 with FL, seven with other B‐NHL, and four with MCL) were evaluable for ORR, and 40 patients had received rituximab‐containing prior chemotherapeutic regimens. For the 39 patients with FL, the ORR was 49% [95% confidence interval (CI): 32·4, 65·2] and the median PFS was 20 months (95% CI: 11·2, 29·7). Major toxicities were manageable grade 3/4 thrombocytopenia and neutropenia. Vorinostat offers sustained antitumour activity in patients with relapsed or refractory FL with an acceptable safety profile. Further investigation of vorinostat for clinical efficacy is warranted.  相似文献   
88.
89.
Context: A broad spectrum of GnRH-deficient phenotypes has been identified in individuals with both mono- and biallelic GNRHR mutations. Objective: The objective of the study was to determine the correlation between the severity of the reproductive phenotype(s) and the number and functional severity of rare sequence variants in GNRHR. Subjects: Eight hundred sixty-three probands with different forms of GnRH deficiency, 46 family members and 422 controls were screened for GNRHR mutations. The 70 subjects (32 patients and 38 family members) harboring mutations were divided into four groups (G1-G4) based on the functional severity of the mutations (complete or partial loss of function) and the number of affected alleles (monoallelic or biallelic) with mutations, and these classes were mapped on their clinical phenotypes. Results: The prevalence of heterozygous rare sequence variants in GNRHR was significantly higher in probands vs. controls (P < 0.01). Among the G1-G3 groups (homozygous subjects with successively decreasing severity and number of mutations), the hypogonadotropic phenotype related to their genetic load. In contrast, subjects in G4, with only monoallelic mutations, demonstrated a greater diversity of clinical phenotypes. Conclusions: In patients with GnRH deficiency and biallelic mutations in GNRHR, genetic burden defined by severity and dose is associated with clinical phenotype. In contrast, for patients with monoallelic GNRHR mutations this correlation does not hold. Taken together, these data indicate that as-yet-unidentified genetic and/or environmental factors may combine with singly mutated GNRHR alleles to produce reproductive phenotypes.  相似文献   
90.
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