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101.
As the explosive growth of the electric vehicle market leads to an increase in spent lithium-ion batteries (LIBs), the disposal of LIBs has also made headlines. In this study, we synthesized the cathode active materials Li[Ni1/3Mn1/3Co1/3]O2 (NMC) and Li[Ni1/3Mn1/3Co1/3Fe0.0005Al0.0005]O2 (NMCFA) via hydroxide co-precipitation and calcination processes, which simulate the resynthesis of NMC in leachate containing trace amounts of iron and aluminum from spent LIBs. The effects of iron and aluminum on the physicochemical and electrochemical properties were investigated and compared with NMC. Trace amounts of iron and aluminum do not affect the morphology, the formation of O3-type layered structures, or the redox peak. On the other hand, the rate capability of NMCFA shows high discharge capacities at 7 C (110 mAh g−1) and 10 C (74 mAh g−1), comparable to the values for NMC at 5 C (111 mAh g−1) and 7 C (79 mAh g−1), respectively, due to the widened interslab thickness of NMCFA which facilitates the movement of lithium ions in a 2D channel. Therefore, iron and aluminum, which are usually considered as impurities in the recycling of LIBs, could be used as doping elements for enhancing the electrochemical performance of resynthesized cathode active materials.  相似文献   
102.
BackgroundVancomycin is the treatment of choice for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Current guidelines recommend giving an initial loading dose (LD) of 25–30 mg/kg to rapidly increase the serum concentration. However, high-quality evidence for the clinical benefit of LD is lacking. Herein, we aim to examine the association between vancomycin LD and clinical outcome.MethodsA retrospective cohort study was conducted on adult patients treated for MRSA pneumonia with vancomycin in medical intensive care units from April 2016 to August 2018. MRSA pneumonia was defined by the Centers for Disease Control and National Healthcare Safety Network definition. The primary outcome was the clinical cure of pneumonia. Secondary outcome measures included time to pharmacokinetic (PK) target attainment, microbiological cure, acute kidney injury, and all-cause mortality.ResultsA total of 81 patients were included; of these 22 (27.2%) received LD. The mean initial dose was significantly higher in the LD group. Clinical cure was similar in both groups (68.2% vs. 66.1% in the LD and non-LD groups, respectively; P=0.860). No significant difference was observed in the microbiological cure, all-cause mortality, and incidence of acute kidney injury. Furthermore, no difference was observed in terms of time to PK target attainment (69.2 vs. 63.4 h in the LD and non-LD groups, respectively; P=0.624). Vancomycin minimum inhibitory concentration of <2 mg/L was identified as an independent predictive factor for clinical cure in multivariable analysis, whereas vancomycin LD was not.ConclusionsInitial LD is not associated with better clinical outcome or rapid pharmacological target attainment in critically ill patients with MRSA pneumonia. Further studies are warranted to provide better evidence for this widely recommended practice.  相似文献   
103.
BackgroundThis meta-analysis was conducted to compare the procedural and early outcomes of aortic valve replacement (AVR) using rapid deployment valve (RD group) versus sutureless valve (SU group).MethodsA literature search of 5 online databases was conducted. The primary outcomes were mean transvalvular pressure gradient (MPG) after AVR, the incidence of paravalvular leak (PVL) and the need for a permanent pacemaker implantation (PPI). The secondary outcomes included aortic cross-clamp (ACC) and cardiopulmonary bypass (CPB) times, early mortality and other postoperative complications, such as atrial fibrillation, bleeding reoperation and stroke.ResultsEight articles were included, and all outcomes except MPG after AVR in matched valve sizes were extracted from 7 studies (RD group =842 patients and SU group =1,386 patients). The pooled analysis demonstrated a lower MPG in the RD group than in the SU group, with mean difference (MD) of 2.64 mmHg. The pooled risk ratios of any PVL and grade ≥2 (or moderate) PVL were not significantly different between the groups; however, the incidence of PPI was significantly lower in the RD group than in the SU group, with a risk ratio of 0.69. The pooled analyses showed that the ACC and CPB times were significantly longer in the RD group than in the SU group, with weighted MDs of 8.74 (P<0.001) and 9.94 (P<0.001) minutes, respectively. The risks of early mortality and other postoperative complications were not significantly different between the groups.ConclusionsAVR using RD valve was associated with better valve hemodynamics in terms of the MPG than AVR using SU valve, and better outcomes were observed in the RD group regarding PPI. Procedural times were longer in AVR using RD valve than SU valve. Early clinical outcomes showed no difference between RD and SU valve.  相似文献   
104.
105.
BACKGROUND: The nonlifting sign is widely used for evaluating the invasion depth of colorectal tumors, and it is commonly accepted that EMR is contraindicated for colorectal tumors with a nonlifting sign because of the probability of massive submucosal invasion. OBJECTIVE: To identify the clinicopathologic factors that affect the nonlifting sign in submucosal invasive colorectal carcinoma (SICC). DESIGN: Details regarding a history of biopsy, postbiopsy days, tumor location, tumor configuration, tumor size, depth of submucosal invasion, histologic type, adenomatous remnants, and angiolymphatic invasion were studied in relation to the nonlifting sign. SETTING: National Cancer Center, Korea. PATIENTS: The study involved 76 patients with SICC treated by endoscopic or surgical resection, in whom the tumor was examined for the nonlifting sign from 2001 to 2006. RESULTS: The nonlifting sign was observed in 15 cases (19.7%). A deep submucosal invasion, a history of biopsy, and the absence of adenomatous remnants were identified as factors affecting the nonlifting sign in univariate and multivariate analyses (P < .05). An increase in the number of postbiopsy days was associated with the nonlifting sign in endoscopically resectable SICC, and all 11 sm1 cancer cases with fewer than 21 postbiopsy days showed lifting. CONCLUSIONS: A history of biopsy and the absence of adenomatous remnants, in addition to deep submucosal invasion, were found to influence the nonlifting sign in SICC. It may be best that mechanical stimulation such as forceps biopsies are minimized before EMR, and EMR should be tried as soon as possible if biopsy was performed.  相似文献   
106.
This study investigated the process of shopping addiction as maladaptive responses regarding buying behavior. A qualitative approach was designed by inductive, interpretative, and constructionist nature of qualitative research. The research participants were recruited from internet websites providing consumer news, recruiting information of consumer panels or monitors, and castings of actors or models. In-depth interviews were done to solicit experiences of shopping. Content analysis was used to derive concepts regarding experiences of compulsive buying. Five concepts were derived, which were described and illustrated as sequential phases of shopping addiction: Phase 1. Retail therapy,Filling up emptiness with shopping”; Phase 2. Denial,Ignoring overconsumption”; Phase 3. Debt-ridden,Ran out of money, while nothing left”; Phase 4. Impulsive buying,Driving ones-self to hasty buying”; and Phase 5. Compulsive buying,It is crazy but I cannot stop”. The results of this study clarifies the basic understanding of people who engage in compulsive buying and provide educational resources for professionals engaged in helping people with compulsive buying disorder.  相似文献   
107.
Laparoscopic gastrectomy became an option in the treatment of early gastric cancer (EGC) in clinical practice. However, whether laparoscopic surgery for grossly EGC-mimicking advanced gastric cancer (AGC) patients is oncologically safe long-term is still controversial.We retrospectively analyzed 472 patients with AGC who were diagnosed as clinical EGC. Patients received laparoscopic or open gastrectomy with standard lymph node (LN) dissection from January 2007 to February 2015. We used a 1:3 propensity score matching method for the analysis. The matching factors were age, sex, body mass index, American Society of Anesthesiologists score and pathologic stage. After the matching process, we evaluated the 5-year overall survival and the cumulative incidence curve of recurrence.All of the analyzed patients were pathologically diagnosed with AGC after surgery (grossly EGC-mimicking AGC). The median (range) duration of follow-up was 58.0 (0–132) months. After propensity score matching, 31.5% of patients in the laparoscopy group had D1+ LN dissection and 99.2% of patients in the open group had D2 LN dissection. The 5-year overall survival rate between the laparoscopy (n = 92) and open groups (n = 244) were not significantly different (95.3% versus 91.4%, P = .224). There was no significant difference between the cumulative recurrence incidence curves of the matched groups (P = .319).Laparoscopic surgery for grossly EGC-mimicking AGC might be safe in terms of long-term survival outcome. After confirming grossly EGC-mimicking AGC in the final pathology report, no additional surgery might be required.  相似文献   
108.
109.
The present study sought to elucidate the role of induction and consolidation therapy in elderly patients. We retrospectively collected data of 477 patients who were aged over 60 years at the time of acute myeloid leukemia (AML) diagnosis. The median overall survival (OS) was 339 days in the induction group (n = 266) and 86 days in the best supportive care group (n = 211) (P < 0.001). In the induction group, the complete remission (CR) rate was 58.3 %, and treatment-related death was 15.4 %. Successful induction was related to good performance [Eastern Cooperative Oncology Group (ECOG <2)] [hazard ratio (HR) 3.215; P = 0.002]. Mortality correlated with failure to achieve CR (HR 4.059; P < 0.001) and poor performance status (ECOG >2) (HR 2.731; P = 0.035). In CR patients, poor karyotype and absence of consolidation (HR 2.313; P = 0.003) correlated with mortality. More than one cycle of consolidation was associated with better OS (P < 0.001). Lack of salvage therapy was associated with mortality in patients who did not achieve CR (HR 3.223; P = 0.005). Intensive induction in patients with good performance and >1 cycle of consolidation after CR may be the best strategy for improving OS in elderly AML patients.  相似文献   
110.
This study was designed to evaluate the prevalence of chromosomal abnormalities and to identify the specific abnormalities associated with poor prognosis. A total of 2,474 patients whose conventional cytogenetics were available at the time of diagnosis were evaluated via a nationwide registry. Normal metaphase cytogenetics was observed in 2,012 patients (81.3%). Among the 462 patients with chromosomal abnormalities, there were 161 (34.8%) patients with hyperdiploidy, 197 (42.6%) with pseudodiploidy, 79 (17.1%) with hypodiploidy, and 25 (5.5%) with near-tetraploidy. Deletion 13 (Δ13) in metaphase was observed in 167 patients (6.8%). Fluorescent in situ hybridization (FISH) was carried out in 967 patients (39.1%), and 66 (13.7%) out of 482 and 63 (10.3%) out of 611 patients were positive for t(4;14) and del(17p), respectively. With a median follow-up duration of 25.1 months, the median overall survival (OS) was 51.2 months (95% confidence interval, 46.5–55.9 months). In univariate analysis, the following four chromosomal abnormalities were significantly associated with a poor survival outcome: Δ13, hypodiploidy, del(13q) in FISH, and del(17p) in FISH. In the subsequent multivariate analysis, in which del(13q) and del(17p) in FISH were excluded due to a relatively low number of patients, Δ13 and hypodiploid status were independently associated with a poor survival outcome after adjusting for important clinical factors, including age, sex, performance, beta2-microglobulin, albumin, and lactate dehydrogenase (LDH). Using conventional metaphase cytogenetics, we confirmed that both Δ13 and hypodiploid status were robust poor prognostic factors. The metaphase karyotyping should remain the primary cytogenetic tool and an essential investigation for risk stratification in newly diagnosed multiple myeloma patients.  相似文献   
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