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31.
This review describes the sex and gender differences in COVID-19 presentation, treatment, and outcomes. We discuss the differences between the sexes in susceptibility to infection, the role of sex chromosomes on the body's immunologic response and the influence of hormones on the body's response to the virus. Additionally, the sex differences in clinical and laboratory presentation, complications of infection and outcomes, as well as differences in response to treatment and prevention are reviewed.  相似文献   
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Tumorigenesis and metastasis are frequently associated with altered structure and expression of oligosaccharides on cell surface glycoproteins and glycolipids. The expression of sialylated glycoconjugates has been shown to change during development, differentiation, disease and oncogenic transformation. Abnormal sialylation in cancer cell is a distinctive feature associated with malignant properties including invasiveness and metastatic potential. The alterations in sialylation is accompanied by changes in sialic acid, sialidase activity, sialyltransferase (ST) activity or sialoproteins. The present review summarizes the reports on alterations of sialic acid, linkage specific STs and sialoproteins, sialidase activity together with different subtypes of ST and sialidases mRNA expressions in various cancers like lung, breast, oral, cervical, ovarian, pancreatic etc. Sialic acids are widely distributed in nature as terminal sugars of oligosaccharides attached to proteins or lipids. The increase shedding of sialic acid observed in malignant tumors may be due to different types of sialidases. The amount of sialic acid is governed by levels of sialidases and STs. Various types of STs are also involved in formation of different types sialylated tumor associated carbohydrate antigens which plays important role in metastasis. The alterations associated with sialylation aids in early diagnosis, prognosis and post treatment monitoring in various cancers. Recently newer drugs targeting different interplays of sialylation have been developed, which might have profound effect in inhibiting sialylation and thus cancer metastasis and infiltration.  相似文献   
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Breast Cancer Research and Treatment - Extending adjuvant endocrine therapy (ET) beyond 5 years has been shown to improve outcomes in breast cancer; however, limited data are available...  相似文献   
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Background: Emergency medicine residents frequently perform invasive procedures, including tube thoracostomy (TT), that inherently place patients at risk for complications. Objectives: The purpose of the study was to assess the prevalence and types of complications from TT in an academic emergency department (ED). Methods: A combined prospective and retrospective, observational study of all patients who had TT between December 2002 and January 2006 was performed. Exclusion criteria included age < 15 years and tube placement at an outside facility. Complications detected in the ED were defined as immediate, whereas those discovered later were defined as delayed. Complications requiring corrective surgical intervention, administration of blood products, or intravenous antibiotics were defined as major. Bivariate and multivariate analyses were used to identify operator and patient factors associated with complications. Results: TTs were placed in 242 patients, and 90 (37%; 95% confidence interval [CI] 31.1–43.3%) experienced a complication. Major complications included one intercostal artery laceration, one retroperitoneal placement, and empyema in 2 patients. In multivariate analysis, blunt injury excluding motor vehicle accidents (odds ratio [OR] 2.57; 95% CI 1.27–5.21) and spontaneous pneumothorax (OR 3.84; 95% CI 1.80–8.18) were associated with all complications. TT size < 36 French and blunt injury excluding motor vehicle accidents were associated with immediate complications and spontaneous pneumothorax was associated with delayed complications. Conclusions: The vast majority of complications from TT in the ED were minor. The prevalence of complications was consistent with previous reports of TTs placed by non-emergency-medicine-trained physicians outside the ED. The findings can be used to identify avoidable complications and improve residency training.  相似文献   
37.
In this study, we define the correlation between LV volumes (both LV end-diastolic volume [LVEDV] and LV end-systolic volume [LVESV]) and ejection fraction (EF) on 64 slice multi-detector computed tomography (MDCT). We also determine the accuracy of all the LV volume (LVV) parameters to detect LV systolic dysfunction (LVSD) and investigate the feasibility of using LVV as a surrogate of LVSD on prospectively gated imaging to prevent the radiation exposure of retrospective imaging. 568 patients undergoing 64-detector MDCT were divided into 2 groups: Group 1—subjects without any heart disease and LVEF ≥ 50%; and Group 2—patients with coronary artery disease and LVEF < 50% (defined as LVSD). The LVV (LV cavity only) and Total LV volume (cavity + LV mass) at end-systole and end-diastole (LVESV, Total LVESV, LVEDV and Total LVEDV) were measured. The upper limit values (mean + 2 SD) of all LVV parameters in Group 1 were used as the reference criterion to diagnose LVSD in Group 2. An exponential correlation was found between LVEF and all the LVV parameters. The specificity to detect LVSD in Group 2 was >90% and the sensitivity was 88.9, 83.3, 61.3 and 74.9% by using LVESV, Total LVESV, LVEDV and Total LVEDV, respectively. Systolic and diastolic LV volumes had a high correlation with LVEF and a high accuracy to detect LVSD. Thus, on prospectively triggered imaging, ventricular volumes can predict patients with reduced LVEF, and appropriate referrals can be made.  相似文献   
38.
Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVES

To report the heterogeneity in the treatment of patients with cT1 urothelial carcinoma by different surgeons, and to report outcomes in patients with and without bacillus Calmette‐Guérin (BCG) treatment.

PATIENTS AND METHODS

We retrospectively reviewed 396 patients who had undergone a re‐staging transurethral resection (TUR) for cT1 bladder cancer. We assessed both differences in the treatment by surgeon, and the association of early treatment with BCG with recurrence, progression and bladder cancer‐specific death.

RESULTS

Muscle was captured in the re‐staging TUR specimen in a median of 76% of patients (range 50–94 when stratified by surgeon). On multivariable analysis there was significant heterogeneity among surgeons in the use of early cystectomy (P < 0.001), deferred cystectomy (P < 0.001), and BCG (P= 0.014). However, there was no significant heterogeneity between surgeons in clinical outcome for recurrence (P= 0.9) and overall survival (P= 0.3). Among 288 patients placed on surveillance, the 5‐year probability (95% confidence interval) of freedom from recurrence was 45 (36–54)% for those receiving and 54 (44–62)% for those not receiving early BCG. On multivariable analysis, early BCG was not significantly associated with recurrence (P= 0.14). The cumulative incidence of progression was ≈10% for both groups, and the cumulative incidence of bladder cancer‐specific death was ≈7% for both groups. The cumulative incidence of deferred cystectomy before progression was 14% for those receiving and 15% for those not receiving early BCG.

CONCLUSIONS

There is a significant variability among surgeons in the management of patients with T1 disease. The similar outcome for the BCG‐treated and ‐untreated patients in our study is most likely confounded by patient selection.  相似文献   
39.
Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVE

To determine the effect of a deep and narrow pelvis on apical positive surgical margins (PSM) at radical prostatectomy (RP), controlling for other clinical and pathological variables and surgical approach, i.e. open retropubic (RRP) vs laparoscopic (LRP), as apical dissection is expected to be more challenging at RP with a prostate situated deep in a narrow pelvis.

PATIENTS AND METHODS

From July 2003 to January 2005, 512 consecutive patients with preoperative prostate magnetic resonance imaging (MRI) underwent RRP or LRP with no previous radio‐ or hormonal therapy. An additional 74 patients with preoperative MRI undergoing RP from December 2001 to June 2007 who had an apical PSM were also included, with 586 patients comprising the study population. Bony and soft‐tissue pelvic dimensions, including interspinous distance (ISD), bony (BFW) and soft tissue (SW) pelvic width, apical prostate depth (AD) and symphysis pubis angle, were measured on preoperative MRI. The pelvic dimension index (PDI), bony width index (BWI) and soft‐tissue width index (SWI) were defined as ISD/AD, BFW/AD and SW/AD, respectively. Multivariate logistic regression was used to assess the effect of pelvic dimensions on apical PSM, controlling for surgical approach and clinical and pathological variables.

RESULTS

There was no significant difference in ISD, BFW, SW or symphysis angle between patients with and without apical PSM. The AD was significantly greater in men with an apical PSM and consequently PDI, BWI and SWI were significantly lower in men with an apical PSM. Each of PDI, AD, BWI and SWI was a significant independent predictor of apical PSM, independent of surgical approach, and other clinicopathological variables. The main limitations of the study were that it was retrospective, and the relatively few patients with apical PSM.

CONCLUSIONS

Apical prostate depth is an independent risk factor for apical PSM at RP. MRI pelvimetry might allow for preoperative planning of the approach to RP.  相似文献   
40.

BACKGROUND:

Chemoprevention with systemic retinoids has demonstrated promise in decreasing the incidence of new primary nonmelanoma skin cancers (NMSCs) in immunocompromised post‐transplantation recipients. There is limited evidence for the use of systemic retinoids in the nontransplantation patient. To the authors' knowledge, this is the first randomized controlled trial to assess the efficacy of acitretin as a chemopreventive agent in nontransplantation patients at high‐risk for NMSC.

METHODS:

The study was designed as a prospective, randomized, double‐blind, placebo‐controlled clinical trial. To test the possible skin cancer‐preventing effect of a 2‐year treatment with acitretin, 70 nontransplantation patients aged ≥18 years who had a history of ≥2 NMSCs within 5 years of trial onset were randomized to receive either placebo or acitretin 25 mg orally 5 days per week. The primary outcome measure was the rate of new NMSC development.

RESULTS:

Seventy patients were randomized to receive either acitretin alone (N = 35) or placebo (N = 35). During the 2‐year treatment period, the patients who received acitretin did not have a statistically significant reduction in the rate of new primary NMSCs (odds ratio, 0.41; 95% confidence interval, 0.15‐1.13; 54% vs 74%; P = .13). However, using the incidence of new NMSC, the time to new NMSC, and total NMSC counts, an umbrella test indicated a significant trend that favored the use of acitretin (chi‐square statistic, 3.94; P = .047). The patients who received acitretin reported significantly more mucositis and skin toxicities compared with the patients who received placebo.

CONCLUSIONS:

Although there was not a statistically significant benefit observed with the use of acitretin, this may have been the result of low statistical power. Cancer 2012;. © 2011 American Cancer Society.  相似文献   
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