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21.
Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode, and its properties compared with that prepared using batch processing. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions. Scanning electron microscopy (SEM) established that in the thin film microfluidic platform, the PSF particles are sheet-like, for short reaction times, and fibrous for long reaction times, in contrast to spherical like particles for the polymer prepared using the conventional batch synthesis. The operating parameters of the VFD (rotational speed of the glass tube, its tilt angle and temperature) were systematically varied for establishing their effect on the molecular weight (Mw), glass transition temperature (Tg) and decomposition temperature, featuring gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) respectively. The optimal VFD prepared PSF was obtained at 6000 rpm rotational speed, 45° tilt angle and 160 °C, for 1 h of processing with Mw ∼10 000 g mol−1, Tg ∼158 °C and decomposition temperature ∼530 °C, which is comparable to the conventionally prepared PSF.

Polysulfone (PSF) was prepared under high shear in a vortex fluidic device (VFD) operating in confined mode. This involved reacting the pre-prepared disodium salt of bisphenol A (BPA) with a 4,4′-dihalodiphenylsulfone under anhydrous conditions.  相似文献   
22.
The aim of the present study was to evaluate the oncological outcomes of radical cystectomy followed by orthotopic urinary diversion in male patients with urothelial bladder carcinoma involving prostatic stroma (pT4a). A total of 1964 patients with urothelial bladder carcinoma who underwent cystectomy between 1971 and 2008 were retrospectively analyzed. Among them, male patients with pT4aN0M0 disease at cystectomy and orthotopic urinary diversion were identified and included in the analysis. Exclusion criteria were perioperative mortality and primary urethrectomy. The outcomes were urethral recurrence, local recurrence, recurrence‐free survival and overall survival. Univariate and log–rank statistics were used to examine associations between variables and outcome. A total of 33 patients (1.7%) entered the study with a median age of 71 years. Median follow up was 4.8 years (range 0.1–21 years). A total of two urethral recurrences (6%) occurred at a median of 2.4 years after cystectomy. No patient had local recurrence. The 5‐year recurrence‐free survival and overall survival was 56% ± 10% and 56% ± 9%, respectively. The probability of urethral and local recurrence after orthotopic diversion in pT4a urothelial bladder carcinoma patients is low. Thus, orthotopic urinary diversion appears to be oncologically safe in this patient population.  相似文献   
23.

Background

The serum neutrophil–lymphocyte ratio (NLR) is associated with outcomes in several solid organ cancers, including hepatocellular carcinoma (HCC).

Methods

We reviewed our experience in patients with HCC who underwent transarterial chemoembolization (TACE) as the initial treatment. Serum complete blood counts were used to calculate the NLR before and after TACE. The Kaplan–Meier method was used to determine survival and significant differences between groups by the log-rank test.

Results

There were 103 patients identified who underwent TACE for HCC. The median age was 60.5 years. Median overall survival was 12.6 (95 % confidence interval 8.3–17) months. Median survival in patients with a high preprocedural NLR was 4.2 months compared to 15 months in those with a normal NLR (p = 0.021). In those whose NLR either rose 1 month after treatment or remained elevated, survival was worse compared to those who normalized or remained normal (18.6 vs. 10.6 months, p = 0.026). The same was true at 6 months (21.3 vs. 9.5 months, p = 0.002). An unresponsive NLR was associated with very poor outcome (median survival 3.7 months). Multivariate analysis of clinicopathologic factors showed that presence of extrahepatic disease and high NLR were independent factors associated with worse survival.

Conclusions

Our study demonstrates that periprocedural trends of serum NLR are associated with outcome in unresectable HCC undergoing TACE. Serum NLR is easy to calculate from a routine complete blood count with differential. Along with liver function, serum NLR may be helpful to clinicians in providing prognostic information and monitoring response to therapy.  相似文献   
24.
Abstract

Objective: Misophonia is a neurophysiological disorder, phenotypically characterized by heightened autonomic nervous system arousal which is accompanied by a high magnitude of emotional reactivity to repetitive and pattern-based auditory stimuli. This study identifies the prevalence of psychiatric symptoms in misophonia sufferers, the association between severity of misophonia and psychiatric symptoms, and the association between misophonia severity and gender.

Methods: Fifty-two misophonia sufferers, 30 females (mean age?=?40.93 ± 15.29) and 22 males (mean age?=?51.18 ± 15.91) were recruited in our study and they were diagnosed according the criteria proposed by Schröder et al. The participants were evaluated by the A-MISO-S for the severity of misophonia and the MINI to assess the presence of psychiatric symptoms.

Results: The most common comorbid symptoms reported by the misophonia patients were respectively PTSD (N?=?8, 15.38%), OCD (N?=?6, 11.53%), MDD (N?=?5, 9.61%), and anorexia (N?=?5, 9.61%). Misophonia severity was associated with the symptoms of MDD, OCD, and PTSD as well as anorexia. There was an indication of a significant difference between men and women in the severity of misophonic symptoms.

Conclusion: Our findings highlight the importance of recognizing psychiatric comorbidity among misophonia sufferers. The presence of these varying psychiatric disorders’ features in individuals with misophonia suggests that while misophonia has unique clinical characteristics with an underlying neurophysiological mechanism, may be associated with psychiatric symptoms. Therefore, when assessing individuals with misophonia symptoms, it is important to screen for psychiatric symptoms. This will assist researchers and clinicians to better understand the nature of the symptoms and how they may be interacting and ultimately allocating the most effective therapeutic strategies.  相似文献   
25.
Male infertility affects 7 % of the male population, and 10 % of infertile men are azoospermic. In these instances, using microsurgical testicular sperm extraction (m-TESE) and intra-cytoplasmic sperm injection (ICSI) helps a significant number of patients. However, in vitro differentiation of diploid germ cells to mature haploid germ cell has the potential to benefit many others, including pediatric cancer survivors who have previously cryopreserved their immature testicular tissue prior to starting gonadotoxic cancer treatment as well as men with spermatogenic arrest. This systematic review evaluates and summarizes half a century of researchers’ efforts towards achieving in vitro spermatogenesis in mammalian species. A myriad of experimental assays and approaches has been developed using whole testis tissue or separated single cells from testis in two- or three-dimensional cell culture systems (2D versus 3D). Recent advances in the mammalian in vitro spermatogenesis, particularly in murine and nonhuman primate systems, hold promise towards translating the availability of in vitro spermatogenesis models in the human clinical setting in the near future.  相似文献   
26.

Introduction

We hypothesized that an elevated preoperative alkaline phosphatase (AP) predicted worse outcomes for patients undergoing transarterial chemoembolization (TACE) for neuroendocrine tumor (NET) liver metastases.

Methods

We reviewed all patients who underwent TACE for metastatic NET between 2009 and 2013. Survival was evaluated using preprocedure variables.

Results

One hundred and nine patients underwent 210 TACE procedures. The average age was 57.7 years (range 20–78). Primary sites included pancreas (N?=?20), other gastrointestinal (N?=?52), lung (N?=?9), and unknown (N?=?28). The tumor was grade 1 in 68 (62 %), grade 2 in 21 (19 %), and grade 3 in 3 (3 %). Extrahepatic disease was present in 54 (50 %) and greater than 50 % hepatic tumor burden by imaging in 63 (58 %). Elevated bilirubin occurred in 8 (7 %), elevated AP in 22 (20 %), elevated ALT in 21 (19 %), and elevated AST in 41 (38 %). Univariate predictors included tumor grade (43 vs 27 vs 21 months, p?=?0.015), hepatic tumor burden (59 vs 37 months, p?=?0.009), and elevated AP (59 vs 23 months, p?<?0.001). On multivariate analysis, only elevated AP (p?=?0.001) predicted worse survival.

Conclusions

Elevated AP prior to TACE for metastatic NET portends a worse survival outcome, even more so than tumor grade or extent of hepatic disease.
  相似文献   
27.
OBJECTIVE: To evaluate the efficacy of aminophylline infusion as a painkiller compared with placebo in patients with acute renal colic. PATIENTS AND METHODS: From March to August 2005, 141 patients with clinical renal colic, who were under 60 years of age, had no history of heart or hepatic failure, asthma, theophylline or beta blocker use, reaction to methylxantines, pregnancy or breast feeding, and were not prescribed spasmolytic or analgesics, entered our study. They were randomly assigned to receive either 375 mg of aminophylline or placebo infusion under double blind conditions. Pain intensity was recorded using a visual analog scale (VAS), before drug administration and 30 and 60 minutes afterwards. The drug effectiveness was defined as > or =40% decrease in pain intensity 60 minutes after the onset of infusion, without exacerbation during the following 4 hours. RESULTS: Seventy patients received aminophylline; it was effective in 45 (64%; 95% confidence interval 52-75%). Alternatively, placebo was effective in 12 of 71 control patients (17%; 95% confidence interval 9-28%); (P < 0.001). Thirty and 60 minutes after administration, aminophylline reduced pain by 24% and 39% respectively, as compared with 6% and 8% pain reduction in the placebo group. CONCLUSION: This prospective study provides remarkable information about the efficacy of aminophylline on pain relief and decreasing narcotic usage in symptomatic urinary calculi. It is safe, inexpensive, with minute side effects and can be considered a good alternative or additive to narcotic analgesics in the management of renal colic.  相似文献   
28.

Introduction

The interval from presentation with systemic inflammatory response syndrome (SIRS) to the start of antibiotic administration affects mortality in patients with sepsis. However, patients with subarachnoid hemorrhage (SAH) often develop SIRS directly from their brain injury, making it a less useful indicator of infection. We therefore hypothesized that SIRS would not be a suitable trigger for antibiotics in this population.

Methods

We examined the time from the development of SIRS until antibiotic initiation and its relationship to long-term neurological outcomes in patients with nontraumatic SAH. Patients’ baseline characteristics, time of antibiotic administration, and hospital course were collected from retrospective chart review. The primary outcome, 6-month functional status, was prospectively determined using blinded, structured interviews incorporating the modified Rankin Scale (mRS).

Results

Sixty-six of 70 patients with SAH during the study period had 6-month follow-up and were included in this analysis. SIRS developed in 57 patients (86 %, 95 % CI 78–95 %). In ordinal logistic regression models controlling for age and illness severity, the time from SIRS onset until antibiotic initiation was not associated with 6-month mRS scores (OR per hour, 0.994; 95 % CI 0.987–1.001).

Conclusions

In this cohort of patients with SAH, time from SIRS onset until antibiotic administration was not related to functional outcomes. Our results indicate that SIRS is nonspecific in patients with SAH, and support the safety of withholding antibiotics in those who lack additional evidence of infection or hemodynamic deterioration.  相似文献   
29.

Background

The classic cardiovascular complication of chronic obstructive pulmonary disease (COPD) is cor pulmonale or right ventricular (RV) enlargement. Most studies of cor pulmonale were conducted decades ago.

Objectives

This study sought to examine RV changes in contemporary COPD and emphysema using cardiac magnetic resonance (CMR) imaging.

Methods

We performed a case-control study nested predominantly in 2 general population studies of 310 participants with COPD and control subjects 50 to 79 years of age with ≥10 pack-years of smoking who were free of clinical cardiovascular disease. RV volumes and mass were assessed using magnetic resonance imaging. COPD and COPD severity were defined according to standard spirometric criteria. The percentage of emphysema was defined as the percentage of lung regions <−950 Hounsfield units on full-lung computed tomography; emphysema subtypes were scored by radiologists. Results were adjusted for age, race/ethnicity, sex, height, weight, smoking status, pack-years, systemic hypertension, and sleep apnea.

Results

Right ventricular end-diastolic volume (RVEDV) was reduced in COPD compared with control subjects (−7.8 ml; 95% confidence interval: −15.0 to −0.5 ml; p = 0.04). Increasing severity of COPD was associated with lower RVEDV (p = 0.004) and lower RV stroke volume (p < 0.001). RV mass and ejection fraction were similar between the groups. A greater percentage of emphysema also was associated with lower RVEDV (p = 0.005) and stroke volume (p < 0.001), as was the presence of centrilobular and paraseptal emphysema.

Conclusions

RV volumes are lower without significant alterations in RV mass and ejection fraction in contemporary COPD, and this reduction is related to the greater percentage of emphysema on computed tomography.  相似文献   
30.
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