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81.
BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients.  相似文献   
82.
ObjectiveTo investigate the role of the deubiquitinase ubiquitin C-terminal hydrolase L1 (UCHL1) in hypertension and retinopathy in the spontaneously hypertensive rat (SHR).MethodsWistar–Kyoto (WKY) rats and SHRs were administered the UCHL1 inhibitor LDN57444 (20 μg/kg/day) for 4 months. Pathological changes were detected with hematoxylin and eosin, immunofluorescence, and dihydroethidium staining. The mRNA and protein expression of UCHL1 were examined by real-time PCR and immunoblotting analysis.ResultsAt 6 months of age, SHRs showed significantly increased mRNA and protein levels of UCHL1 in the retina compared with WKY rats. Moreover, SHRs exhibited significantly increased central retinal thickness, inflammation, and reactive oxygen species production compared with WKY rats, and these effects were markedly attenuated by systemic administration of the UCHL1 inhibitor LDN57444. The beneficial effects of LDN57444 were possibly associated with reduced blood pressure and the inactivation of several signaling pathways.ConclusionUCHL1 is involved in hypertension and retinopathy in SHRs, suggesting that UCHL1 may be used as a potential therapeutic target for treating hypertensive retinopathy.  相似文献   
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The crystal structure of poly(4,4′‐diphenylsulfonyl terephthalamide) (pt‐PSA) is studied by X‐ray diffraction and molecular simulation. Although the number of observed reflections is limited to warrant a precise determination of the unit cell structure and symmetry, a reasonable monoclinic unit cell is suggested with dimensions of a = 0.645 nm, b = 0.488 nm, c = 3.010 nm, and γ = 122.5°. A twofold molecule with two monomeric units forming a large zigzag conformation satisfies the X‐ray diffraction data. A layer structure is formed in the crystal phase, which is stabilized by the hydrogen bond between ? NH and ? C?O and the parallel‐displaced π–π stacking from the distortional coplanarity of the benzene rings and amide group.

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85.
As an intermediate filament protein, cytokeratin 8 (CK8) exerts multiple cellular functions. Moreover, it has been identified as a marker of notochord cells, which play essential roles in human nucleus pulposus (NP). However, the distribution of CK8 positive cells in human NP and their relationship with intervertebral disc degeneration (IDD) have not been clarified until now. Here, we found the percentage of CK8 positive cells in IDD (25.7±4.14%) was significantly lower than that in normal and scoliosis NP (51.9±9.73% and 47.8±5.51%, respectively, p<0.05). Western blotting and qRT-PCR results confirmed the down-regulation of CK8 expression in IDD on both of protein and mRNA levels. Furthermore, approximately 37.4% of cell clusters were CK8 positive in IDD. Taken together, this is the first study to show a down-regulated CK8 expression and the percentage of CK8 positive cell clusters in IDD based upon multiple lines of evidence. Consequently, CK8 positive cells might be considered as a potential option in the development of cellular treatment strategies for NP repair.  相似文献   
86.
The objective of this study is to investigate the effects of high pressure processing (HPP) on the quality of mango smoothies and the inactivation of microorganisms therein, with heat treatments used as the control. Comparative analysis was conducted on the microbiological changes in the mango smoothies subjected to HPP at 400–600 MPa for 0–15 min. The total plate count (TPC) and the yeast and mold (YM) counts were found to be significantly inactivated through increases in the pressure and treatment time (p < 0.05). Conditions of 90 °C/20 min (HT), 500 MPa/8 min (HPP-500) and 600 MPa/5 min (HPP-600) were, thus, selected as the subsequent treatment for a storage study at 4 °C for 15 days, since these conditions had similar inactivation effects on TPC and YM. After 15 days of storage, the TPC was found to have increased by 3.87, 3.54 and 3.36 log10 cycles in the mango smoothies treated by HT, HPP-500 and HPP-600, respectively, while the YM counts remained at less than 1 log10 cycle in all samples. During storage, compared to the HT and HPP-600 samples, both the color and viscosity at 100 s−1 of samples treated by HPP-500 were found to be better maintained. Carotene content was better retained in storage after the HPP process than after the HT process. However, the different treatments had no effect on the pH nor on the total soluble solids (TSS) in the samples. The study ascertained that HPP-500 is able to ensure both the microbial safety and the quality of mango smoothies more effectively than HT and HPP-600.

The objective of this study is to investigate the effects of high pressure processing (HPP) on the quality of mango smoothies and the inactivation of microorganisms therein, with heat treatments used as the control.  相似文献   
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89.
目的 系统评价多黏菌素静脉联合鞘内或脑室内注射对多重耐药鲍曼不动杆菌的疗效及安全性。方法 计算机检索PubMed、Embase、CNKI、VIP、万方数据库等数据库,检索时间为建库至2019年6月,筛选有关多黏菌素静脉联合鞘内或脑室内给药治疗多重耐药鲍曼不动杆菌感染的文献,采用RevMan 5.3软件对提取的数据进行Meta分析。结果 纳入7篇文献、178例患者。Meta分析结果显示,静脉联合鞘内或脑室内组的临床死亡率(OR=0.18, 95%CI:0.09~0.37, P<0.00001)低于静脉组、细菌清除率(OR=20.40, 95%CI:5.94~70.12, P<0.00001)高于静脉组;两组不良反应发生率无统计学差异(OR=0.60, 95%CI: 0.16~2.23, P=0.44)。结论 多黏菌素静脉联合鞘内或脑室内给药治疗多重耐药鲍曼不动杆菌颅内感染疗效优于静脉滴注,安全性无显著差异。  相似文献   
90.
Objective To clarify the long-term renal prognosis and related risk factors of progression for IgA nephropathy (IgAN) patients who achieved remission under current therapy. To identify the target value of the serum albumin level for Chinese patients with IgAN. Methods The patients with biopsy-proven primary IgAN in Nephrology Department of Renji Hospital in Shanghai were studied.The survival of renal and the relationships between clinical parameters and renal outcome were assessed. Results A total of 369 patients between Jan 2005 and Dec 2010 were included with a median follow-up time of 49.0 (38.0-65.8) months. All the subjects had achieved a complete remission (CR) or partial remission (PR) following six months’ therapy after diagnosis. Progressive renal disease had occurred in 61 cases at the end of follow-up. Three variables had a significant independent effect on renal outcome in patients achieving remission under current therapy regimen for IgAN, including time-average serum creatinine (TA-Scr) [HR(95%CI): 1.03(1.01-1.04)], time-average serum albumin (TA-Alb) [HR(95%CI): 0.83 (0.69-0.99)], and eGFR ratio within one year [HR(95%CI): 0.00(0.00-0.01)]. By multivariate Cox analyses, each 1 g/L drop of TA-Alb was related with 17.2% increase in the risk of renal progression. The ROC curve indicated that combination of serum albumin at baseline and during a long-term had a more significant value in prediction of renal outcome than independent predictor alone. By Kaplan-Meier analyses, patients with TA-Alb﹤38 g/L had a 10.4 fold sincreased risk of progressive disease compared with that of TA-Alb﹥38 g/L. Conclusions IgAN patients with lower eGFR ratio, higher TA-Scr and lower TA-Alb would progress to ESRD more quickly, and serum albumin during follow-up is important for predicting IgAN progression.  相似文献   
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